BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Dissolution Behavior of Lead Borate Glass under Simulated Geologic al Disposal Conditions DTSTART;VALUE=DATE-TIME:20171031T031500Z DTEND;VALUE=DATE-TIME:20171031T033000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1217@events01.synchrotron.org.au DESCRIPTION:Speakers: Atsushi Mukunoki (JGC Corporation)\nLead borate glas s vitrified at a low temperature is regarded as one of the promising immob ilization materials of Iodine-129 which will be removed from a spent AgI f ilter generated from reprocessing plants and may cause significant effect onto long term safety of geological disposal.\nImmersion tests in various solutions have been conducted to understand glass dissolution behaviors in possible geological disposal conditions. Boron dissolved with the highest rate in all types of the solutions and was regarded as an index element t o represent the glass dissolution rate. On the other hand\, lead dissolved with a far slower rate. Chemical species and the possible precipitating m inerals of lead were examined by a geochemical calculation code for typica l underground water. Altered glass surfaces were investigated by SEM\, TEM and XRD. XRD analysis showed that the main constituent phase of the alter ed layer was hydrocerussite\, Pb3(CO3)2(OH)2 that was predicted by the geo chemical simulation as well\n\nhttps://events01.synchrotron.org.au/event/5 1/contributions/1217/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1217/ END:VEVENT BEGIN:VEVENT SUMMARY:Radionuclide containing solid phases on the inner surface of a Zir caloy-4 cladding tube DTSTART;VALUE=DATE-TIME:20171030T061500Z DTEND;VALUE=DATE-TIME:20171030T063000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1215@events01.synchrotron.org.au DESCRIPTION:Speakers: Ernesto González-Robles Corrales (Karlsruhe Institu te of Technology)\nZircaloy claddings of fuel rods for nuclear reactors ar e considered as first technical barrier for retention of radionuclides pro duced in the nuclear fuel. The integrity of the cladding is influenced by various processes during reactor operation and beyond\, e.g. oxidation\, h ydrogen uptake\, PCI\, fission product precipitation\, -decay\, and rad iation damage. Composition of agglomerates found on the inner surface of t he plenum section of an irradiated Zircaloy-4 cladding tube are investigat ed by SEM-EDX\, XPS\, and synchrotron based techniques.\nµ-XRF investigat ions show uranium hot spots and fission products. Grooves from cladding tu be production contain uranium residues from fuel pellets insertion. Pluton ium\, cesium and rubidium are present ibidem. Another type of agglomerates contains cesium\, rubidium\, and minor amounts of actinides. Cesium and r ubidium may originate from three sources: uranium traces within the claddi ng\, uranium residues in surface grooves\, and Cs/Rb released from subjace nt fuel pellets.\n\nhttps://events01.synchrotron.org.au/event/51/contribut ions/1215/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1215/ END:VEVENT BEGIN:VEVENT SUMMARY:Atomistic simulation of interfaces in glass/crystal composites for nuclear waste forms DTSTART;VALUE=DATE-TIME:20171101T033000Z DTEND;VALUE=DATE-TIME:20171101T034500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1213@events01.synchrotron.org.au DESCRIPTION:Speakers: Paul C. M. Fossati (Imperial College London)\nHigh-L evel Waste (HLW) resulting from fuel reprocessing is immobilised in a boro silicate glass matrix\, particularly in France and the UK.\nSome HLW compo nents have higher melting points than the glass\, and thus never disolve i nto the melt.\nOther crystalline phases may also form during fabrication d ue to limited solubility.\nSeparation could also occur later through a pro cess of devitrification.\nThe resultant waste form may therefore demonstra te significant heterogeneity with secondary crystal phases embedded in a glass matrix.\n\nThe purpose of this study is to improve understanding of the issues associated with such microstructures in vitrified wasteforms.\ nWe will present results from atomistic simulations showing properties of glass/crystal interfaces in a surrogate composite formed of (Na$_{2}$)$_{x }$(SiO$_{2}$)$_{1-x}$ glass and rutile TiO$_{2}$ crystals.\nThe potentials employed have been widely used for glass materials. We will discuss their applicability to glass/crystal composite structures.\nWe will show struct ural and energetic features predicted for these interfaces and consider th e effect of radiation damage.\n\nhttps://events01.synchrotron.org.au/event /51/contributions/1213/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1213/ END:VEVENT BEGIN:VEVENT SUMMARY:Pyrolysis and Plasma applied to Nuclear ion Exchange Resins Treatm ent DTSTART;VALUE=DATE-TIME:20171101T223000Z DTEND;VALUE=DATE-TIME:20171101T224500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1212@events01.synchrotron.org.au DESCRIPTION:Speakers: hugo luis bianchi (Gerencia Química\, Comisión Nac ional de Energía Atómica\, CAC\, Av. Gral. Paz 1499 (1650) Buenos Aires\ , Argentina / ECyT\, UNSAM\, Martín de Irigoyen 3100 (1650) San Martín\, Argentina)\nSpent ion exchange resins (IER) represent an important waste stream that is generated during the operation of both light and heavy-wate r reactors. Over the past 60 years of nuclear activity Argentina has accum ulated over 300 m3 of spent IERs that to this day remain interim storage. With a view toward achieving a significant volume reduction and improved p roduct stability we are investigating a two-step process involving initial low-temperature (\n\nhttps://events01.synchrotron.org.au/event/51/contrib utions/1212/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1212/ END:VEVENT BEGIN:VEVENT SUMMARY:Synroc Waste Treatment Plant for fission-based Molybdenum-99 Produ ction DTSTART;VALUE=DATE-TIME:20171030T011500Z DTEND;VALUE=DATE-TIME:20171030T014500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1211@events01.synchrotron.org.au DESCRIPTION:Speakers: Gerry Triani (ANSTO)\nA new nuclear medicine facilit y is being built which will enable ANSTO to meet both domestic and global demand for Molybdenum-99. Co-located on the site will be an innovative was te treatment facility that deploys ANSTO’s Synroc technologies\; a waste form tailored for immobilizing all the waste elements and fission product s and an integrated process line for converting intermediate level liquid waste into a solid compact via hot isostatic pressing (HIP)\, producing a durable waste form suitable for final disposal. This presentation will pr ovide a high-level overview of the program\, including various stages of d evelopment that are important in building this first of a kind nuclear was te treatment plant.\n\nhttps://events01.synchrotron.org.au/event/51/contri butions/1211/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1211/ END:VEVENT BEGIN:VEVENT SUMMARY:Apparent Diffusion Coefficients Consistent with Sorption Derived B ased on Changes in Depth Profiles of Radiocaesium in Soil Contaminated by the Fukushima Nuclear Accident and Future Prediction of Depth Profile DTSTART;VALUE=DATE-TIME:20171102T000000Z DTEND;VALUE=DATE-TIME:20171102T001500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1210@events01.synchrotron.org.au DESCRIPTION:Speakers: Haruo Sato (Okayama University)\nH. Sato and M. Yosh ii\, Okayama University\, 3-1-1\, Tsushima-naka\, Kita-ku\, Okayama-shi\, Okayama 700-8530\, Japan\n\nThe accident at the Fukushima Daiichi Nuclear Power Plant occurred following the Great East Japan Earthquake in March 20 11\, and led to the release of volatile radionuclides (RNs) which were dep osited on the surrounding environment in the Fukushima prefecture. The aut hors conducted twice investigations on the depth profiles of RNs in soil a t 11 locations in the city of Nihonmatsu and the towns of Kawamata and Nam ie.\nThe apparent diffusion coefficients (Da) of Cs-134 and Cs-137 were de rived from changes in the depth profiles\, and the distribution coefficien ts (Kd) also calculated from the relation with Da. The calculated Kd-value s ranged 1E4-1E5 ml/g\, which were consistent with Kd-values (2\,080-61\,0 00 ml/g) obtained by a batch method. The Da-values of both nuclides were a pproximately of order 1E-14 m2/s and movement by diffusion was very slow. Furthermore\, the authors simulated change in the depth profiles of both n uclides for 30 years following the accident.\n\nhttps://events01.synchrotr on.org.au/event/51/contributions/1210/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1210/ END:VEVENT BEGIN:VEVENT SUMMARY:Unique capabilities and methods for analysing nuclear waste form m aterials using ANSTO’s landmark infrastructure DTSTART;VALUE=DATE-TIME:20171101T054500Z DTEND;VALUE=DATE-TIME:20171101T060000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1209@events01.synchrotron.org.au DESCRIPTION:Speakers: Gabriel Murphy (University of Sydney)\nIn situ inves tigations of nuclear waste form related materials under extreme conditions are highly desirable for understanding and optimising applications of the se materials\, however they are often exceedingly challenging from a safet y and radiological perspective. As a part of our investigations into actin ide materials\, we have developed a number of novel experimental methodolo gies which utilize ANSTO’s landmark research infrastructure\, the Opal n uclear reactor and Australian Synchrotron\, towards examining the behaviou r of actinide materials related to nuclear waste forms under extreme condi tions. This presentation will highlight some of our successes in advancing the study of actinide and nuclear materials including\n\n - High temperat ure in situ redox chemistry of uranium using X-ray absorption spectroscopy .\n\n - The behaviour of uranium oxides under high pressure ( >6 GPa) usin g neutron diffraction.\n\n - High temperature studies of thorium oxides us ing synchrotron X-ray and neutron diffraction.\n\n - Chemistry of uranium oxides under high purity hydrogen gas reduction and high temperature condi tions (1000 °C) using synchrotron X-ray diffraction.\n\nhttps://events01. synchrotron.org.au/event/51/contributions/1209/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1209/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards a ‘3S toolbox’ for providing safety\, security and saf eguards at geological disposal of high-level radioactive waste and spent f uel DTSTART;VALUE=DATE-TIME:20171030T220000Z DTEND;VALUE=DATE-TIME:20171030T223000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1207@events01.synchrotron.org.au DESCRIPTION:Speakers: Irmgard Niemeyer (Forschungszentrum Jülich GmbH)\nS afety\, security and safeguards aspects regarding the geological disposal of high-level radioactive waste and spent fuel are usually addressed separ ately. Thus\, apparently different methods and techniques exist for each o f the three “S’s”. However\, by identifying both synergies in overla pping methods or techniques and differences in the requirements with respe ct to safety\, security and safeguards\, advantage of inherent synergies a nd conflicting requirements can be taken at the same time. [1]\nThe paper identifies methods and technologies (a ‘3S toolbox’) that would be bes t suited for the holistic consideration of safety\, security and safeguard s provisions. Such a toolbox could include\, first\, measurement technique s for spent fuel verification already at the encapsulation plant. Second\, a set of measures based on remote monitoring\, nuclear measurements\, con tainment and surveillance for application at the encapsulation plant\, the geological repository and transfers between both. Third\, measures for de tecting unauthorized activities\, e.g. the analysis of open source informa tion including satellite imagery\, geophysical monitoring and environmenta l sampling. \n\n[1] Niemeyer\, I.\, Deissmann\, G.\, Bosbach\, D.\, Bri dging nuclear safety\, security and safeguards at geological disposal of h igh-level radioactive waste and spent nuclear fuel\, In: International Con ference on the Safety of Radioactive Waste Management\, IAEA-CN-242\, 21-2 5 November 2016\, Vienna\, Austria\, Book of Paper\, Session 3d\, p.20-24. \n\nhttps://events01.synchrotron.org.au/event/51/contributions/1207/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1207/ END:VEVENT BEGIN:VEVENT SUMMARY:Advances in conditioning of low and intermediate nuclear waste DTSTART;VALUE=DATE-TIME:20171029T224500Z DTEND;VALUE=DATE-TIME:20171029T231500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1205@events01.synchrotron.org.au DESCRIPTION:Speakers: Michael Ojovan (International Atomic Energy Agency)\ , Miklos (Mike) Garamszeghy (Nuclear Waste Management Organization\, Canad a)\nRadioactive waste with widely varying characteristics is generated fro m the operation and maintenance of nuclear reactors\, nuclear fuel cycle f acilities\, research facilities and medical facilities and the through the use of radioisotopes in industrial applications. The waste needs to be tr eated and conditioned as necessary to provide wasteforms acceptable for sa fe storage and disposal. Conditioning of radioactive waste is an important step to prepare waste for long-term storage or disposal and includes the following processes: \n• Immobilization which may or may not also pro vide volume reduction\, including (a) Low temperature processes and (b) Th ermal processes\; \n• Containerization for (a) Transport\, (b) Storag e\, and (c) Disposal\; \n• Overpacking of primary containers (a) Prio r to disposal and (b) In a disposal facility as part of disposal process. \nConditioning consists of operations that produce a waste package suitabl e for handling\, transportation\, storage and/or disposal and may be perfo rmed for a variety of reasons including standardization of practices and/o r wasteforms\, technical requirements for waste stability in relation to a repository design or safety case\, technical requirements related to wast e transportation\, societal preferences\, regulatory preferences\, etc. Th is report aims to give an overview of recent advances in conditioning of l ow and intermediate nuclear waste.\n\nhttps://events01.synchrotron.org.au/ event/51/contributions/1205/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1205/ END:VEVENT BEGIN:VEVENT SUMMARY:Chemical Durability of Borosilicate Glass-Ceramic High-Level Waste Form in Dilute and Static Conditions DTSTART;VALUE=DATE-TIME:20171031T004500Z DTEND;VALUE=DATE-TIME:20171031T010000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1204@events01.synchrotron.org.au DESCRIPTION:Speakers: Jarrod Crum (PNNL)\nA borosilicate glass-ceramic was te form is being developed to significantly increase waste loading of high -level waste relative to single phase glass. The glass-ceramic waste form is comprised of approximately 70% borosilicate glass\, 20% oxyapatite (X2 Ln8Si6O26)\, and 10% powellite (XMoO4)\, by mass\, where X = alkaline eart h and Ln = lanthanides. Understanding the overall corrosion behavior of t he glass-ceramic is complicated because each phase corrodes at a different rate and there are matrix effects. Durability of the multiphase waste fo rm was investigated with single-pass flow-through and static leach testing \, but the results were convoluted because elements were present in multip le phases. In an effort to deconvolute the corrosion process of the full waste form\, additional corrosion testing was performed on the full waste form and individually-synthesized phases (remainder glass\, oxyapatite\, a nd powellite). Results of these tests are presented and comparisons betwee n the glass-ceramic waste form and individual phases are discussed.\n\nhtt ps://events01.synchrotron.org.au/event/51/contributions/1204/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1204/ END:VEVENT BEGIN:VEVENT SUMMARY:Porosity distribution in a heterogeneous clay-rich fault core DTSTART;VALUE=DATE-TIME:20171102T031500Z DTEND;VALUE=DATE-TIME:20171102T033000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1203@events01.synchrotron.org.au DESCRIPTION:Speakers: Ville Nenonen (University of Helsinki)\nFault zones influence the mechanical properties and seismological behaviour of the Ear th’s crust and also the migration and trapping of sub-surface fluids. In addition to natural processes\, their behaviour has broad implications to issues such as oil and gas production\, the sequestration of carbon dioxi de and the geological disposal of radioactive wastes. \nRecent investigati ons carried out at the Tournemire Underground Laboratory (URL)\, run by th e French Institute for Radiological Protection and Nuclear Safety (IRSN) h ave highlighted heterogeneous fault gouge strengthening processes within a small-scale vertical strike slip fault affecting a low-permeability shale . \nThe aim of this project is to determine precisely\, in an apparently h eterogeneous and poorly consolidated brecciated rock\, the porosity variat ions in and around the different fault gouges and define their relationshi p to chemical and/or mechano-chemical processes.\n\nhttps://events01.synch rotron.org.au/event/51/contributions/1203/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1203/ END:VEVENT BEGIN:VEVENT SUMMARY:Sodalite waste forms for iodine DTSTART;VALUE=DATE-TIME:20171101T044500Z DTEND;VALUE=DATE-TIME:20171101T050000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1202@events01.synchrotron.org.au DESCRIPTION:Speakers: John McCloy (Washington State University)\nIodine-12 9\, released in the off-gas stream during nuclear fuel reprocessing\, is p roblematic due to its long half-life\, high mobility in the earth’s envi ronment\, incorporation into the human thyroid\, and difficulty in immobil izing it using traditional vitrification methods. Iodosodalite (Na8Al6Si6O 24I2) has been considered as to immobilize iodine-129 due to feasibility o f synthesis at low temperature (\n\nhttps://events01.synchrotron.org.au/ev ent/51/contributions/1202/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1202/ END:VEVENT BEGIN:VEVENT SUMMARY:Effects of Li\, Ca\, Fe\, and B on NaAlSiO4 nepheline crystallizat ion in high level waste glasses DTSTART;VALUE=DATE-TIME:20171031T010000Z DTEND;VALUE=DATE-TIME:20171031T011500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1201@events01.synchrotron.org.au DESCRIPTION:Speakers: John McCloy (Washington State University)\nOwing to high concentrations of Al2O3 from dissolved fuel cladding and Na2O from ba sification of the waste\, about half of the high-level waste by volume at Hanford\, Washington\, USA is rich in both Na and Al. Formulations of hig h waste-loading glasses result in lower amounts of SiO2\, which often lead s to undesirable precipitation of nepheline (NaAlSiO4). Nepheline crystal lization can be affected by modifiers (Li\, Ca) added to lower viscosity a nd improve electrical conductivity of the melt. Also\, B is frequently ad ded to reduce viscosity\, and Fe is present in varying amounts from steel tank corrosion. Given the existence of various natural minerals of the st oichiometries (Na\,Li\,Ca0.5)(Al\,Fe\,B)SiO4\, we sought to study the effe cts of substitution in the stoichiometric nepheline glass on the resulting crystallization. We summarize here several years of work\, including cha racterization by nuclear magnetic resonance\, vibrating sample magnetometr y\, Raman spectroscopy\, thermal analysis\, x-ray diffraction\, electron m icroscopy\, and electron microprobe.\n\nhttps://events01.synchrotron.org.a u/event/51/contributions/1201/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1201/ END:VEVENT BEGIN:VEVENT SUMMARY:Effect of thiosulfate on the SCC behavior of carbon steel welds ex posed to concrete pore water under anoxic conditions DTSTART;VALUE=DATE-TIME:20171102T023000Z DTEND;VALUE=DATE-TIME:20171102T030000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1200@events01.synchrotron.org.au DESCRIPTION:Speakers: Sebastien CAES (SCK-CEN)\nThe Supercontainer (SC) is the reference concept for the post-conditioning of vitrified high-level n uclear waste and spent fuel in Belgium. It comprises a prefabricated concr ete buffer that completely surrounds a carbon steel overpack. Welding is b eing considered as a final closure technique of the carbon steel overpack in order to ensure its water tightness. Welding is known to induce residua l stresses near the weld zone\, which may lead to an increased susceptibil ity to stress corrosion cracking (SCC). In this study\, slow strain rate t ests were conducted to study the SCC behavior of plain and welded P355 QL2 grade carbon steel exposed to an artificial concrete pore water solution that is representative for the SC concrete buffer environment. The tests w ere performed at 140°C\, a constant strain rate of 5 × 10-7 s-1 and at o pen circuit potential under anoxic conditions. The effect of thiosulfate o n the SCC behavior was investigated up to levels of 5.35 mM S2O32- (600 mg L-1).\n\nhttps://events01.synchrotron.org.au/event/51/contributions/1200/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1200/ END:VEVENT BEGIN:VEVENT SUMMARY:Effect of Carbonate on Lanthanides Migration Behavior in Compacted Bentonite DTSTART;VALUE=DATE-TIME:20171102T041500Z DTEND;VALUE=DATE-TIME:20171102T043000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1199@events01.synchrotron.org.au DESCRIPTION:Speakers: Kazuya Idemitsu (Kyushu university)\nThe apparent di ffusion coefficients of La\, Nd\, Eu\, Dy\, Er and Lu in compacted bentoni tes were investigated in various bicarbonate concentration. The apparent d iffusion coefficients of lanthanides tended to decrease with increase of d ry density. In the lower bicarbonate conditions than 0.25 M lanthanum had the largest diffusion coefficient of ca. 10-13 m2/s at 1.0 Mg/m3 and diffu sion coefficient was small as atomic number becomes big. On the other hand in the higher bicarbonate conditions than 0.25 M Lutetium had the largest diffusion coefficient and diffusion coefficient was small as atomic numbe r becomes small. Especially Lanthanum and Neodymium had smaller diffusion coefficient than 10-14 m2/s even at 1.0 Mg/m3. Diffusion coefficient of Eu ropium was around 10-13 m2/s at 1.0 Mg/m3 and less influence of bicarbonat e concentration. Diffusion coefficient of Lutetium increased from 2 x 10- 14 to 10-12 m2/s with bicarbonate concentration up to 1.0 M.\n\nhttps://ev ents01.synchrotron.org.au/event/51/contributions/1199/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1199/ END:VEVENT BEGIN:VEVENT SUMMARY:Synthesis and characterization of brannerite UTi2O6 DTSTART;VALUE=DATE-TIME:20171031T221500Z DTEND;VALUE=DATE-TIME:20171031T223000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1198@events01.synchrotron.org.au DESCRIPTION:Speakers: adel mesbah (ICSM Marcoule\, France)\nThe share of n uclear energy in order to supply electricity continues to increase\, which makes a growing need for more uranium resources. Currently uraninite (UO2 ) and coffinite (USiO4) are the two most abundant and exploited minerals. With the exhausting of these resources\, other minerals are currently cons idered and are subject to multiple studies. Among them brannerite (UTi2O6) represents the third source of tetravalent uranium on Earth and could be considered for uranium recovery.1 However\, brannerite is known to be very difficult to dissolve quantitatively even in very aggressive conditions. 2 Consequently\, the multiparametric study of dissolution of this phase ha s to be studied in details.\nIn this work\, we first focused on the synthe sis of pure brannerite by developing new methods of synthesis free from he avy grinding steps in contrary of the alkoxide/nitrate based routes.3 The impact of several parameters were studied such as heating temperature of s ynthesis\, holding time and atmosphere. Therefore a new method was develop ed based on the preparation of hydroxides mixture then it direct heating u nder Ar or N2 atmosphere for 72 hours at 1300°C.\nFinally\, dissolution e xperiments were carried out under different conditions in order to provide multiparametric expression of the normalized dissolution rate.\n\n**Refer ences**\n\n1. IAEA. Uranium extraction technology. Technical reports se ries 1993\, 359\, \n2. Gilligan\, R.\; Nikoloski\, A. N. The extraction of uranium from brannerite – A literature review. Minerals Engineering 2015\, 71\, 34-48.\n3. Ringwood\, A. E.\; Kesson\, S. E.\; Reeve\, K. D .\; Levins\, D. M.\; Ramm\, E. J. In Radioactive Forms for the Future\; Lu tze\, W.\, Ewing\, R. C.\, Ed.\; 1988\; p 233.\n\nhttps://events01.synchro tron.org.au/event/51/contributions/1198/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1198/ END:VEVENT BEGIN:VEVENT SUMMARY:Preparation of Ln1-2xCaxThxPO4.nH2O rhabdophane-type as low precur sors to monazite-Cheralite ceramics DTSTART;VALUE=DATE-TIME:20171101T001500Z DTEND;VALUE=DATE-TIME:20171101T003000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1197@events01.synchrotron.org.au DESCRIPTION:Speakers: adel mesbah (Institut de Chimie Séparative de Marco ule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bag nols-sur-Cèze cedex\, France)\nMonazite\, i.e. LnPO4 (Ln = La-Gd)\, has b een widely studied as specific ceramic for the conditioning of trivalent a nd tetravalent actinides.1 Owing to its chemical and structural flexibilit y\, the monazite allows a variety of possible substitutions following diff erent mechanisms.2 Among them\, the so-called cheralite-family\, i.e. Ln1- 2xCaxAnIVxPO4. In this frame\, the major part of protocols reported in the literature was based on solid-state chemistry routes. However\, this meth od requires the use of repetitive grinding steps and re-heating of actinid e bearing powders and usually forms heterogeneous compounds in term of cat ionic distribution. \nIn this work\, we present an alternative method base d on wet chemistry route to prepare thorium-based cheralites. It is based on the initial precipitation of Ln1-2xCaxThxPO4.nH2O3 low temperature prec ursors crystallizing in the rhabdophane type structure (monoclinic\, C2 sp ace group).4 A multiparametric study allowed the determination of the appr opriate conditions to form homogeneous and single phase powders. Then thes e hydrated precursors were converted to monazite-cheralite ceramics throug h thermal treatment. A coupled in situ PXRD/TGA allowed the identification of the different dehydration steps before the irreversible stabilization of the cheralite anhydrous compounds.5 Moreover\, since such hydrated phas es could also control the release of radionuclides from the ceramics in th e field of underground repository\, dissolution and solubility experiments have been finally carried out.\n\n**References**\n\n1. Dacheux\, N.\; Clavier\, N.\; Podor\, R. American Mineralogist 2013\, 98 (5-6)\, 833-847. \n2. Clavier\, N.\; Podor\, R.\; Dacheux\, N. Journal of the European C eramic Society 2011\, 31 (6)\, 941-976.\n3. Qin\, D.\; Mesbah\, A.\; Ga usse\, C.\; Szenknect\, S.\; Dacheux\, N.\; Clavier\, N. Journal of Nuclea r Materials 2017\, 492\, 88-96.\n4. Mesbah\, A.\; Clavier\, N.\; Elkaim \, E.\; Gausse\, C.\; Kacem\, I. B.\; Szenknect\, S.\; Dacheux\, N. Crysta l Growth & Design 2014\, 14 (10)\, 5090-5098.\n5. Mesbah\, A.\; Clavier \, N.\; Elkaim\, E.\; Szenknect\, S.\; Dacheux\, N. Journal of Solid State Chemistry 2017\, 249\, 221-227.\n\nhttps://events01.synchrotron.org.au/ev ent/51/contributions/1197/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1197/ END:VEVENT BEGIN:VEVENT SUMMARY:Emulsions as a powerful tool to design silica monoliths able to se lectively uptake radioactive caesium DTSTART;VALUE=DATE-TIME:20171101T220000Z DTEND;VALUE=DATE-TIME:20171101T221500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1196@events01.synchrotron.org.au DESCRIPTION:Speakers: Jeremy Causse (Institut de Chimie Séparative de Mar coule (ICSM) - UMR5257 - CEA Marcoule)\nThis work deals with the developme nt of new templating routes to design porous nanostructured materials with innovative properties and/or easier to prepare. For example\, we have sho wn that copper hexacyanoferrate nanoparticles could stabilize High-Interna l Phase Emulsions or HIPE (**Mayer et al.\, J. Coll. Int. Sci.\, 2017\, do i.org/10.1016/j.jcis.2017.05.113**) that can be used in a second step as a template for functionalized monoliths. It is of great interest considerin g that these coordination polymers come from Prussian blue analogues famil y\, the most effective sorbent for caesium\, and therefore relevant in nuc lear decontamination purposes of 137Cs or 134Cs. To be active at oil/water interface and stabilize emulsions\, CuHCF particles have to be modified w ith a polyelectrolyte\, PDDA. The presence of CuHCF all around the oil dro plets of the emulsions makes these particles located all around the macrop ores inside the final silica monolith due to the fact that the oil droplet s are used as a template and should be therefore emptied after sol/gel gel ification of the emulsions in order to create macropores. However\, CuHCF can also be used without any PDDA surface modification. In this case\, CuH CF nanoparticles are hydrophilic and remain in the water phase of the HIPE . The water outer part of the HIPE is the place where sol/gel reactions oc cur. Therefore\, CuHCF nanoparticles are finally located in the monoliths walls if no PDDA is used. However CuHCF nanoparticles are still accessible to caesium in this case due to the mesoporosity of the walls because of t he use of surfactant in this case to stabilize the HIPE (**Causse et al.\, J. Mater. Chem. A\, 2014\, 2\, 9461**). And finally\, we have also develo ped a third synthesis route of functionalized silica monoliths with CuHCF\ , CoHCF and ZnHCF. In this latter exemple\, the HIPE is prepared only with the metal species\, either Cu or Co or Zn. After the sol/gel reaction a m eso/macroporous silica monoliths containing metal species is obtained. And finally after an impregnation step with K4[Fe(CN)6]\, the corresponding m etal hexacyanoferrate particles precipitate inside the porosity of the sil ica monolith (**Sommer-Marquez et al.\, RSC Adv.\, 2016\, 6\, 73475**).\nT his global study showed that we can play with particles of interest in ord er to change their location in the templating soft matter (HIPE) and there fore inside the final monolith. Results of inorganic materials characteriz ation (N2 adsoprtion/desorption\, SAXS\, SEM\, FTIR) as well as Cs sorptio n isotherms will be shown.\n\nhttps://events01.synchrotron.org.au/event/51 /contributions/1196/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1196/ END:VEVENT BEGIN:VEVENT SUMMARY:Thorium incorporation in phosphates matrices: the case of xenotime DTSTART;VALUE=DATE-TIME:20171101T004500Z DTEND;VALUE=DATE-TIME:20171101T010000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1195@events01.synchrotron.org.au DESCRIPTION:Speakers: adel mesbah (ICSM Marcoule\, France)\nThe management and the conditioning of radwaste represents a major challenge in the nucl ear industry. Therefore a variety of host matrices have been studied\, inc luding several phosphate based ceramics.1 They represent promising candida tes for the specific conditioning of actinides (III\, IV) owing to their e asy way of preparation and high chemical durability.2\nThe incorporation o f actinides in such phases has been extensively studied through solid-stat e routes. Thus\, it often requires repetitive grinding steps and re-heatin g to avoid the formation of heterogeneous compounds.3 For such reasons\, t he synthesis of target compounds in aqueous solution were developed to pre pare pure and homogenous phases. \nIn this study\, a particular attention was paid to the incorporation of tetravalent actinides (Th4+\, U4+) in the zircon structure type through the coupled mixed (An(IV) + SiO4 / Ln(III) + PO4) substitution.\nIn this frame\, solid solutions of Er-xThx(PO4)1-x(S iO4)x were obtained in application of the method developed to prepare pure coffinite (USiO4)\, i.e. hydrothermal conditions at 250°C for 7 days.4 T he analysis of the PXRD data showed the formation of single phases. The st ructure crystallizes in the zircon-type structure (I41/amd group\, tetrago nal system) as observed for the end-members ThSiO4 and ErPO4. From Rietvel d refinements\, the formation of a complete solid solution was confirmed i n agreement with the Vegard’s law. A thorough analysis was also carried out by Raman spectroscopy and EXAFS at the Er and Th edges and showed an e xciting structural evolution.5 \n\n**References**\n\n1. Dacheux\, N.\; Clavier\, N.\; Robisson\, A. C.\; Terra\, O.\; Audubert\, F.\; Lartigue\, J. É.\; Guy\, C. Comptes Rendus Chimie 2004\, 7 (12)\, 1141-1152.\n2. Dacheux\, N.\; Clavier\, N.\; Podor\, R. American Mineralogist 2013\, 98 ( 5-6)\, 833-847.\n3. Terra\, O.\; Dacheux\, N.\; Audubert\, F.\; Podor\, R. Journal of Nuclear Materials 2006\, 352 (1)\, 224-232.\n4. Mesbah\, A.\; Szenknect\, S.\; Clavier\, N.\; Lozano-Rodriguez\, J.\; Poinssot\, C .\; Den Auwer\, C.\; Ewing\, R. C.\; Dacheux\, N. Inorganic Chemistry 2015 \, 54 (14)\, 6687-6696.\n5. Mesbah\, A.\; Clavier\, N.\; Lozano-Rodrigu ez\, M. J.\; Szenknect\, S.\; Dacheux\, N. Inorg Chem 2016\, 55 (21)\, 112 73-11282.\n\nhttps://events01.synchrotron.org.au/event/51/contributions/11 95/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1195/ END:VEVENT BEGIN:VEVENT SUMMARY:Modelling the Corrosion of Spent Nuclear Fuel Inside a failed Wast e Container DTSTART;VALUE=DATE-TIME:20171030T033000Z DTEND;VALUE=DATE-TIME:20171030T040000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1192@events01.synchrotron.org.au DESCRIPTION:Speakers: David Shoesmith (Western University)\nThe internatio nally accepted approach for the disposal of spent nuclear fuel is to seal it in corrosion-resistant metal containers and bury it in a stable deep ge ologic repository. If containers were to fail\, and the fuel become expose d to groundwater\, radiolytic corrosion of the fuel could release radionuc lides to the groundwater\, the critical first step in their transport into the environment. Two corrosion fronts will exist within a failed containe r\, one on the fuel surface driven by radiolytic oxidants and a second on the carbon steel vessel sustained by water reduction. Based on an extensiv e series of electrochemical\, corrosion and chemical dissolution studies\, a finite-element based model has been developed to determine this evoluti on in redox conditions and its influence on fuel corrosion. Particular att ention will be paid to the influence of hydrogen\, produced radiolytically and by corrosion of the steel container vessel\, on the corrosion rate.\n \nhttps://events01.synchrotron.org.au/event/51/contributions/1192/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1192/ END:VEVENT BEGIN:VEVENT SUMMARY:NEW ASPECTS OF THE MECHANISM OF HYDROGEN EFFECT ON SPENT FUEL DISS OLUTION DTSTART;VALUE=DATE-TIME:20171030T040000Z DTEND;VALUE=DATE-TIME:20171030T041500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1191@events01.synchrotron.org.au DESCRIPTION:Speakers: Kastriot Spahiu (SKB\, Stockholm\, Sweden and Chalme rs University of Technology\, Gothenburg\, Sweden)\nOur experimental data indicate that the hydrogen effect is a complex phenomenon and has several aspects. The decomposition of hydrogen peroxide on the surface of SIMFUEL is followed by the reaction of the produced hydroxyl radicals with hydrog en to give water\, or their reaction with H2O2 to give O2. Only a very sma ll part of the initial hydrogen peroxide (\n\nhttps://events01.synchrotron .org.au/event/51/contributions/1191/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1191/ END:VEVENT BEGIN:VEVENT SUMMARY:Inert matrix fuel deployment for reducing the plutonium stockpile in reactors DTSTART;VALUE=DATE-TIME:20171101T230000Z DTEND;VALUE=DATE-TIME:20171101T233000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1190@events01.synchrotron.org.au DESCRIPTION:Speakers: Claude Degueldre (Engineering Department\, Lancaster University\, LA1 4YW\, UK)\nAbstract – The 450 reactors operating (Nov. 2016) around the world (30 countries) produce about 100 tonnes of plutoni um annually\, in spent fuel. Some amounts are separated through reprocessi ng. While the recycling of plutonium as MOX fuel derives additional energy from this resource\, it does little to address the issue of growing pluto nium inventories. If a political objective is to reduce the amount of plut onium\, then inert matrix fuel (IMF) provides an option for plutonium dest ruction. More generally\, the utilization of plutonium in IMF provides fle xibility in balancing the quantity of plutonium\, by enabling the net burn ing of plutonium. This approach is viable in existing cores (Gen II&III) t hat already utilize MOX fuel. IMF can be used both to manage plutonium inv entories and to contribute to reduce the long-term radiotoxicity of the sp ent fuel by minor actinide destruction. Some of these IMF materials are al so being considered for Gen IV reactors\, because of their advanced perfor mance\, economics\, safety features\, sustainability\, and application to waste minimization in a closed fuel cycle.\nSeveral promising candidate ma terials have been identified for both fast and thermal reactors: MgO (mag nesia)\, ZrO2 (zirconia)\, SiC (silicon carbide)\, Zr (alloys)\, ZrN (zirc onium nitride)\; some of these have undergone test irradiations and post i rradiation examination. These materials may be used as cylindrical pellets \, prismatic designed blocs\, or as micro-spheres utilized as sphere-pac o r kernels. They can be utilized at the fuel assembly level as prismatic (v ertical or horizontal) set up such as in Light Water Reactors\, Pressured Heavy Water Reactors or Liquid Metal Fast Reactor\, or\, as spherical such as in a High Temperature Gas-cooled Reactor. The fuel itself may be homo geneously composed of IMF or heterogeneously loaded with the IMF and urani um material. The assemblies may be homogeneously or heterogeneously loaded with the IMF\, and the reactor core may be homogeneously or heterogeneous ly loaded with IMF assemblies. These three levels\, i.e. fuel\, assembly a nd core\, of IMF utilization in LWR are considered within a homogeneous-he terogeneous concept scheme as recently reported in the IMF workshop. Model ling and testing IMF fuel performance and safety analysis have progressed. Fabrication methods have also been developed or adapted from existing te chnologies. System studies have identified strategies for both implementat ion of IMF fuel in existing reactors in the shorter term\, as well as in n ew reactors in the longer term. Finally for the backend the burned IMF sho uld be an attractive waste form to dispose or in specific conditions easy to reprocess.\nThe work to date has established the feasibility of these I MF materials\, and core loadings and reactor strategies for utilizing thes e fuels. Further developments are required before commercial deployment of IMF\, which will require additional resources. Additional in-pile irradia tions have been suggested\, both for normal operating and accident conditi ons. Further safety analysis and tests are required. Some development is n eeded for analysis tools and computer programs. Irradiations in commercial reactors should be undertaken in a staged approach as soon as possible: s egmented rods\, full-length rods\, then lead assemblies. IMF can play an important role in the future of nuclear power.\n\nhttps://events01.synchro tron.org.au/event/51/contributions/1190/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1190/ END:VEVENT BEGIN:VEVENT SUMMARY:New route for synthesis of Synroc-like ceramic using non-selective sorbent LHT-9 DTSTART;VALUE=DATE-TIME:20171101T060000Z DTEND;VALUE=DATE-TIME:20171101T061500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1189@events01.synchrotron.org.au DESCRIPTION:Speakers: Bella Zubekhina (researcher\, V.G. Khlopin Radium In stitute (KRI)\, St-Petersburg\, Russia)\nImmobilization of bulk liquid hig h level waste (HLW) in Synroc ceramic is well-known reliable way for final isolation of waste from biosphere. It is proposed the alternative method of synthesis of titanate Synroc-like ceramic. Radionuclide incorporation i nto crystalline titanate host-phases can be provided as a result of direct radionuclide sorption from liquid HLW using non-selective sorbent – lay ered hydrazinium titanate (LHT-9). Such an approach allows excluding expen sive multi-stage procedure of precursor preparation. The precipitate obtai ned after sorption can be easily transformed into Synroc-like ceramic by c old pressing and sintering in air at 1000-1100°. The highly radioactive s amples of titanate ceramic loaded with 10 wt.% of real HLW were synthesize d and studied at KRI hot-cell facility. Chemical durability of these sampl es was tested using MCC-1 static leach test (in distilled water at 90°C) and the leach rate was found to be comparable with Synroc ceramic.\n\nhttp s://events01.synchrotron.org.au/event/51/contributions/1189/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1189/ END:VEVENT BEGIN:VEVENT SUMMARY:A New Method for Production of Glass-Y2Ti2O7 Pyrochlore DTSTART;VALUE=DATE-TIME:20171101T031500Z DTEND;VALUE=DATE-TIME:20171101T033000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1187@events01.synchrotron.org.au DESCRIPTION:Speakers: Linggen Kong (Australian Nuclear Science and Technol ogy Organisation)\nThe actinide immobilisation research group at ANSTO has been investigating pyrochlore glass-ceramics for plutonium immobilisation . A novel method of glass ceramic preparation via a soft chemistry route h as been designed recently. Significant advantages over a more traditional mixed oxide route include removal of the need for an organic solvent in sy nthesis and milling steps\, and product devoid of potentially deficient mi nor phases. Glass-Y2Ti2O7 pyrochlore was fabricated by sintering the mixtu re of glass precursor powder and (YTi)-composite prepared by a soft chemis try route. XRD and Raman confirmed phase pure pyrochlore crystallized in-s itu in amorphous glass matrix at 1200oC. Pyrochlore formation in glass was independent of cooling rates and addition of metal fluorides. Glass matri x was able to accommodate/dissolve small amounts of impurities and the mea n pyrochlore particle size was between 1 and 2 µm in glass.\n\nhttps://ev ents01.synchrotron.org.au/event/51/contributions/1187/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1187/ END:VEVENT BEGIN:VEVENT SUMMARY:New aspects of U(V) chemistry in oxo-materials: from ambient to ex treme conditions DTSTART;VALUE=DATE-TIME:20171101T051500Z DTEND;VALUE=DATE-TIME:20171101T054500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1185@events01.synchrotron.org.au DESCRIPTION:Speakers: Evgeny Alekseev (Forschungszentrum Jülich)\nUsing e xtreme pressure (10GPa/1200°C) we obtained a new modification of U2O5 wit h an extraordinary dense structure. The crystal structure of resulting HP (high pressure)-U2O5 is dramatically differs from ambient pressure polymor ph so called delta-U2O5. The structure of HP-U2O5 is more related to the c ubic UO2 than to the layered delta-U2O5. Using state of the art ab initio methods we reveal the stability ranges of both ambient and high pressure f orms of U2O5 and demonstrated a potential pathway of phase transition unde r pressure.\nIn second case we demonstrated that the pentavalent uranium ( U(V)) can be stabilized in [Ln(UVO2)W4O14] (Ln = Nd-Tm and Y) series via a liovalent substitution of Ca2+ cations. We confirmed U(V) stabilization us ing state of the art methods such as U M4 edge high energy resolution X-ra y absorption near edge structure (HR-XANES).Magnetic study reveals low tem perature ordering of 5f1 and 4fn systems. All the phases tend to demonstra te the antiferromagnetic properties with significant difference between pu re 5f1 system (Y-beating phase) and 5f1-4fn compounds (Nd-Tm).\n\nhttps:// events01.synchrotron.org.au/event/51/contributions/1185/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1185/ END:VEVENT BEGIN:VEVENT SUMMARY:Behaviour of sand-bentonite buffer material of deep geological rep ository under high confining pressure DTSTART;VALUE=DATE-TIME:20171102T033000Z DTEND;VALUE=DATE-TIME:20171102T034500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1184@events01.synchrotron.org.au DESCRIPTION:Speakers: Janaka J. Kumara (Department of Civil Engineering\, Meijo University\, Japan)\nDeep geological repositories have been proposed as a safe waste management system for high-level radioactive wastes. Sand -bentonite buffer materials are used in engineered barrier system of deep geological facilities thank to their excellent swelling properties. In thi s research\, volumetric and strength behaviour of sand-bentonite buffer ma terial under high confining pressures of 1-3MPa were studied using a newly developed double-cell triaxial testing apparatus. The specimens were prep ared with 30% of sand as proposed for geological repositories in Japan. Th e suction behaviour of sand-bentonite specimens were also studied.\n Th e results indicate that the degree of saturation influences the strength a nd volumetric behaviour significantly\, which suggests that local groundwa ter flow affects the performance of buffer material upon decommissioning o f a deep geological repository. It also indicates that suction behavior is significantly affected by the degree of saturation\, although it was less affected by confining pressure.\n\nhttps://events01.synchrotron.org.au/ev ent/51/contributions/1184/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1184/ END:VEVENT BEGIN:VEVENT SUMMARY:Ambient-Cured Geopolymers for Low Level Nuclear Waste Storage DTSTART;VALUE=DATE-TIME:20171031T060000Z DTEND;VALUE=DATE-TIME:20171031T061500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1183@events01.synchrotron.org.au DESCRIPTION:Speakers: Isadora Borba da Busch (UNSW Sydney)\nRadioactive ma terials are used for several key applications in Australia\, and resultant ly\, ~4248 m3 of low level and 656 m3 of intermediate level waste are curr ently stored on site. The present work investigates the development of an ambient-cured geopolymer composition for storage of low level radioactive wastes. These geopolymers were fabricated by ambient curing of mixtures of fly ash and blast furnace slag with an alkaline activator. Samples wer e fabricated both with sand (mortar) and without sand (paste). The cured compositions (25x25x25 mm3 cubes showed high compressive strengths of ~100 MPa. Microstructural and mineralogical characterisation was conducted us ing scanning electron microscopy and X-ray diffraction analysis. The samp les will be subjected to gamma irradiation to simulate exposure from incor porated Cs-137 for a few hundred years at ANSTO. Samples will be removed at different time points (1-12 months) and microstructural and mechanical testing will be done to assess its stability.\n\nhttps://events01.synchrot ron.org.au/event/51/contributions/1183/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1183/ END:VEVENT BEGIN:VEVENT SUMMARY:Synthesis and Structure of Novel Oxide Compounds Containing RE = Y \, Yb\, Gd\, Sm\, and La and M = Zr\, Ti\, and Sn DTSTART;VALUE=DATE-TIME:20171031T220000Z DTEND;VALUE=DATE-TIME:20171031T221500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1182@events01.synchrotron.org.au DESCRIPTION:Speakers: Greg Lumpkin (ANSTO)\nWith the aim of creating novel ceramics with high radiation tolerance and ionic mobility\, multiple samp les with A-B-O stoichiometries ranging from 215 to 227 were synthesized an d characterized by a combination of SEM\, XRD\, and TEM methods. Single-ph ase defect-fluorite-type compounds with A = Sm or Yb and B = Ti\, Zr\, and /or Sn are reported\; whereas\, pyrochlore compounds were also found as a second major RE-phase in numerous samples. We describe some interesting TE M data showing selected area diffraction patterns with complex modulations . The details of the modulation wave vectors observed in these samples are reported in some detail. The use of ionic radii to predict the structure of these ceramics appears to be substantially limited by Sn-O bonding char acteristics and somewhat limited for zirconate compounds. Some single phas e ceramics were irradiated with a low dose of helium and no significant ra diation damage was observed by comparative GIXRD and nano-indentation.\n\n https://events01.synchrotron.org.au/event/51/contributions/1182/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1182/ END:VEVENT BEGIN:VEVENT SUMMARY:The Fabrication and Characterisation of Novel Complex Ceramic Oxid es (Ln2TiO5) For Polyphase Ceramic Waste-Forms. DTSTART;VALUE=DATE-TIME:20171031T230000Z DTEND;VALUE=DATE-TIME:20171031T231500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1181@events01.synchrotron.org.au DESCRIPTION:Speakers: Robert Aughterson (ANSTO)\nThe structure types withi n the Ln2TiO5 (Ln = lanthanides) system have similarities with many of the proposed phases within the titanate ceramic waste-form Synroc. Certain co mpounds might also be suitable for inert matrix fuel applications. Previou s studies have shown a relationship between lanthanide radii and polymorph type for the Ln2TiO5 system. By using multiple lanthanides the average la nthanide radius can be controlled and so the structure. In this study four different combinations of lanthanide titanates were fabricated with the a im of producing single phase\, novel design materials with cubic symmetry. Whilst it is possible to fabricate homogeneous materials with the general Ln2TiO5 stoichiometry using multiple lanthanides there appears to be limi ted solubility. The ratio of the lanthanides influences the final structur e type and also the solubility. The structure type influences the heavy io n irradiation response of these compounds and we report on TEM in-situ exp erimental results related to this.\n\nhttps://events01.synchrotron.org.au/ event/51/contributions/1181/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1181/ END:VEVENT BEGIN:VEVENT SUMMARY:Functionalised Titania and Zirconia Materials for Selective Actini de and Lanthanide Separations DTSTART;VALUE=DATE-TIME:20171101T224500Z DTEND;VALUE=DATE-TIME:20171101T230000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1180@events01.synchrotron.org.au DESCRIPTION:Speakers: Jessica Veliscek Carolan (ANSTO)\nActinides and lant hanides are targets for partitioning from solutions of spent nuclear fuel. Traditionally\, actinide separation processes are based on liquid-liquid extraction. However\, use of solid phase sorbent materials has several adv antages such as the lack of organic solvent wastes. Framework materials ba sed on titania and zirconia have been developed and functionalised with or ganic ligands in order to impart selectivity. Titania and zirconia based f ramework materials were chosen due to their radiolytic and hydrolytic stab ility\, as well as the fact they can be easily converted to transmutation matrices or wasteforms once they are loaded with actinides. The framework materials used vary in complexity from simple nanoparticles to millimetre sized\, spherical\, hierarchically porous beads. In terms of organic ligan ds\, functionalisation with phosphonates\, amines and bistriazinylpyridine (BTP) has been performed to impart selectivity for lanthanides\, uranium or minor actinides.\n\nhttps://events01.synchrotron.org.au/event/51/contri butions/1180/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1180/ END:VEVENT BEGIN:VEVENT SUMMARY:Radioactive Iodine-129 Capture in Mixed Cation Sodalites: ab initi o modelling DTSTART;VALUE=DATE-TIME:20171101T050000Z DTEND;VALUE=DATE-TIME:20171101T051500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1179@events01.synchrotron.org.au DESCRIPTION:Speakers: EUGENIA KUO (Australian Nuclear Science and Technolo gy Organisation)\nSodalites have been investigated experimentally for the capture and long-term containment of iodine-129\, a significant and hazard ous waste product of the nuclear fuel cycle. Sodalites are zeolite-type st ructures commonly occurring in nature in alkaline igneous rocks and having the prototype formula Na$_8$(AlSiO$_4$)$_6$Cl$_2$. The crystal structure is based around $\\beta$-cages consisting of corner-sharing SiO$_4$ and Al O$_4$ tetrahedra. In the centre of the $\\beta$-cage is an anion X. Iodine captured by sodalites sits in the centre of the $\\beta$-cages as iodide anions. Silver iodide (AgI) plays an important role in the capture and sub sequent processing of iodine-129 in the nuclear fuel cycle. Using *ab init io* density functional theory (DFT) modelling\, we investigate the energet ics and feasibility of iodine capture and containment in mixed cation soda lites Na$_{8-x}$Ag$_x$(AlSiO$_4$)$_6$I$_2$\, and compare the results with experimental observations.\n\nhttps://events01.synchrotron.org.au/event/51 /contributions/1179/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1179/ END:VEVENT BEGIN:VEVENT SUMMARY:Advanced Materials and Processes for Application to the Back-end o f the Nuclear Fuel Cycle DTSTART;VALUE=DATE-TIME:20171101T213000Z DTEND;VALUE=DATE-TIME:20171101T220000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1174@events01.synchrotron.org.au DESCRIPTION:Speakers: Vittorio Luca (Comisión Nacional de Energía Atómi ca)\nThe nuclear industry generates a wide variety of radioactive waste st reams during reactor operations and maintenance and in virtually all parts of the fuel cycle. In order to improve the sustainability of the industry it is necessary to develop improved methods and processes for treating\, conditioning and disposing of this waste. The talk will provide an overvie w of research being conducted at the Comisión Nacional de Energía Atómi ca emphasizing the development of novel solid-extractants with the ability to selectively extract radionuclides from complex solutions and with comp ositions that facilitate end-of-life management by being able to be conver ted to extremely stable ceramics. Topics to be covered will include 1) a p roposed process for the conversion of spent polymeric ion exchange resins to stable pyropolymer and carbon materials and their subsequent immobiliza tion\, 2) synthesis of coordination polymers suitable for the selective ex traction of radiolanthanides and their subsequent immobilization\, 3) pote ntial new targets for a cleaner production of Mo-99 and 4) the use of phen olic resins as matrices for spent organic and inorganic ion exchange media .\n\nhttps://events01.synchrotron.org.au/event/51/contributions/1174/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1174/ END:VEVENT BEGIN:VEVENT SUMMARY:Status of Used Nuclear Fuel and Radioactive Waste Long-term Manage ment Programs in Canada DTSTART;VALUE=DATE-TIME:20171030T001500Z DTEND;VALUE=DATE-TIME:20171030T004500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1173@events01.synchrotron.org.au DESCRIPTION:Speakers: Miklos Garamszeghy (Nuclear Waste Management Organiz ation)\nIn Canada\, used CANDU (CANada Deuterium Uranium) nuclear fuel fro m the operation of 22 current and former nuclear power reactors\, as well as several prototype and demonstration reactors\, is stored in water-fille d pools for about seven to ten years before it is transferred to licensed dry storage containers at the nuclear reactor sites. Although safe\, this storage practice requires continuous institutional controls such as securi ty\, safeguards\, monitoring and maintenance. \n\nIn November 2002\, the Canadian Parliament passed the Nuclear Fuel Waste Act (NFWA). It required the major owners of used nuclear fuel in Canada to establish the Nuclear W aste Management Organization (NWMO). The initial phase of the mandate was to perform a three year study of suitable approaches for the safe\, long-t erm management of used nuclear fuel\, and to recommend a preferred approac h to the Government of Canada. The study\, which included extensive dialo g across Canada with elected officials\, specialists and the general publi c\, was completed and the report with a recommendation was submitted to th e Government in November 2005.\n\nIn June 2007\, the Government of Canada approved the recommended Adaptive Phased Management (APM) approach. It is consistent with long-term management best practices adopted by other coun tries with nuclear power programs. The NWMO was given the mandate to impl ement APM.\n\nAPM is both a technical method and a management system. The end point of the technical method is the centralized containment and isola tion of Canada's used fuel in a Deep Geological Repository (DGR) in an are a with suitable geology and an informed and willing host community. APM al so involves the development of a transportation system to move the used fu el from the facilities where it is currently stored to the new site.\nThe management system involves realistic\, manageable phases\, each marked by explicit decision points. It allows for flexibility in the pace and manner of implementation\, and fosters the sustained engagement of people and co mmunities throughout its implementation.\n\nAPM is also designed to meet r igorous safety standards throughout all aspects of its design and implemen tation. As per this approach\, the used fuel will be isolated and containe d in a DGR located in a stable crystalline or sedimentary rock formation a t a nominal depth of 500 m below ground surface in a willing and informed host community.\n\nThe DGR concept contains multiple engineered barriers t o safely contain and isolate the used fuel over the long-term. The geosphe re enclosing the repository provides a natural barrier to protect the wast e form and EBS\, and to mitigate repository releases at time frames releva nt to repository safety.\n\nThis presentation focusses on the current stat us of the APM program but will also briefly discuss the status of other lo ng-term radioactive waste management activities in Canada.\n\nhttps://even ts01.synchrotron.org.au/event/51/contributions/1173/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1173/ END:VEVENT BEGIN:VEVENT SUMMARY:Simplified UK Magnox waste glass alteration layer characterisation using 29Si\, 17O and 25Mg NMR techniques DTSTART;VALUE=DATE-TIME:20171031T030000Z DTEND;VALUE=DATE-TIME:20171031T031500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1172@events01.synchrotron.org.au DESCRIPTION:Speakers: Rui Guo (University of Cambridge)\nThe magnesium con tent of UK Magnox waste glass makes its aqueous durability much poorer tha n glasses such as SON68\, which does not contain Mg. The glass dissolution kinetics is ultimately dependent on the composition/structures of the alt ered layers(1)\, here we try to elucidate formation mechanisms.\n\nAlterat ion layers formed by in-situ precipitation have been discussed widely(2\,3 )\, but any direct identification of precipitated phases is not yet known. The altered layers of simplified Magnox waste glasses were examined using a variety of 17O\, 25Mg and 29Si solid-state NMR techniques. In terms of quantification and species identification\, the Mg containing glass incorp orates 3-4 times the amount of 17O derived from the 17O enriched leachate compared with a Ca glass\, identified as bridging oxygen and hydroxyl oxyg en species. At least two types of amorphous surface phases were characteri sed by proton cross-polarisation (CP) that show local environments simila r to clay mineral phases(4). 25Mg and 29Si NMR spectra corroborate the act ive chemical role of Mg in precipitation and the multiphase nature of the alteration layer.\n\n\n\n 1. Curti\, E. et al. (2006) Applied Geochemistry 21 pp. 1152-1168\n 2. Geisler\, T (2010) Journal of Non-Crystalline Solid s 356 pp. 1458-1465\n 3. Hellmann\, R (2015) Nature Materials 14 pp. 307-3 11\n 4. Thien\, B. et al. (2010) Applied Clay Science 49 pp. 135-141\n\nht tps://events01.synchrotron.org.au/event/51/contributions/1172/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1172/ END:VEVENT BEGIN:VEVENT SUMMARY:Development of solid state MAS NMR techniques for the characteriza tion of alteration products formed during the dissolution of spent nuclear fuel. DTSTART;VALUE=DATE-TIME:20171030T044500Z DTEND;VALUE=DATE-TIME:20171030T050000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1170@events01.synchrotron.org.au DESCRIPTION:Speakers: Beng Thye Tan (University of Cambridge\, Singapore N uclear Research and Safety Initiative)\nThe migration of radionuclides fro m underground nuclear waste repositories will involve the formation of ura nium secondary minerals when ground water reacts with the spent nuclear fu el. \n\nDuring oxic or anoxic spent fuel dissolution\, amorphous phases ca n precede the development of well-defined crystalline mineral phases. Nuc lear magnetic resonance (NMR) can probe the structure of these amorphous a lteration products and trace the evolution of secondary phases. \n\nTo dev elop the technique\, potential secondary phases of $^{17}$O-enriched urani um minerals have been fabricated to establish the oxygen environments of b ecquerelite\, Ca(UO$_2$)$_6$O$_4$(OH).8(H$_2$O)\, andersonite\, Na$_2$Ca(U O$_2$)(CO$_3$)3.6H$_2$O and grimselite\, K$_3$Na(UO$_2$)(CO$_3$)$_3$.(H$_2 $O). These contain calcium (Ca$^2+$)\, carbonate (CO$_3$$^{2+}$)\, and oth er ubiquitous ions. \nSolid state $^{17}$O MAS-NMR spectra of uranium mine rals have been obtained in a 9.39T magnetic field.\n\n Detailed difference s in oxygen local environments such as uranyl bond lengths and interlayer OH and H$_2$O can be distinguished by analyzing the spectra\, which can el ucidate the alteration of UO$_2$ by $^{17}$O water.\n\nhttps://events01.sy nchrotron.org.au/event/51/contributions/1170/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1170/ END:VEVENT BEGIN:VEVENT SUMMARY:Impact of lanthanide elements on the dissolution of uranium dioxid e DTSTART;VALUE=DATE-TIME:20171030T041500Z DTEND;VALUE=DATE-TIME:20171030T043000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1169@events01.synchrotron.org.au DESCRIPTION:Speakers: Nicolas DACHEUX (University of Montpellier)\nDue to the concomitant formation of oxygen vacancies in the fluorite structure\, it was found that the incorporation of trivalent lanthanide elements in Th O2 or CeO2 strongly affect their chemical durability during dissolution or leaching tests [1-4]. On the contrary\, the impact of such elements on th e dissolution of UO2 remains largely unknown. For this purpose\, several l anthanide – uranium mixed based samples incorporating 1 to 20 mol.% of a mixture of lanthanide elements (with the mole ratio : 13 % La \; 7.4 % Y \; 25.6 % Ce \; 12 % Pr \; 42 % Nd) were prepared through quantitative oxa late precipitation. After conversion to the final oxides then sintering\, they were characterized from chemical and microstructural points of view a nd finally submitted to multiparametric dissolution tests in several nitri c acid solutions and at various temperatures. Contrarily to Th- and Ce-bas ed mixed oxides\, the presence of lanthanide elements in UO2 did not affec t significantly the normalized dissolution rates in concentrated nitric ac id solutions (C > 1M). On the contrary\, the effect was more important in less concentrated solutions (e.g. a factor or 100 compared to pure UO2 obs erved in 0.5M HNO3) when the role of surface-controlling reactions on the overall dissolution become predominant. Such observations related to the m acroscopic description of the dissolution were connected to in operando fo llowing of the evolving solid/liquid interface that underlined the prefere ntial dissolution of lanthanide enriched grain boundaries and triple junct ions.\n \n1. Horlait\, D. et al.\, Inorg. Chem.\, 51\, 3868-3878\, 2012\n2 . Horlait\, D. et al.\, J. Nucl. Mater.\, 429\, 237-244\, 2012\n3. Horlait \, D. et al.\, J. Mater. Chem. A\, 2\, 5193-5203\, 2014\n4. Claparede\, L. et al.\, Inorg. Chem.\, 50\, 11702-11714\, 2011\n\nhttps://events01.synch rotron.org.au/event/51/contributions/1169/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1169/ END:VEVENT BEGIN:VEVENT SUMMARY:Effect of platinoid elements on the dissolution of uranium dioxide DTSTART;VALUE=DATE-TIME:20171030T053000Z DTEND;VALUE=DATE-TIME:20171030T060000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1167@events01.synchrotron.org.au DESCRIPTION:Speakers: Nicolas DACHEUX (University of Montpellier)\nDissolu tion or leaching of the spent nuclear fuels (SNF) is a key step either in the field of their reprocessing or their long-term storage in underground repository. Moreover\, SNF contain a wide variety of fission products incl uding platinoid elements (PGM’s) either incorporated in the UO2 matrix\, or present in various separated phases for which the specific impact on t he overall dissolution kinetics has not been yet fully discriminated. In o rder to answer this question\, several samples doped with 0.6 to 3 mol.% o f PGM’s (55 % Ru \; 9.6 % Rh \; 35.4 % Pd) were prepared from hydroxide based synthesis [1\,2]. After conversion then sintering\, the prepared pel lets were submitted to multiparametric dissolution tests in various media (0.1 to 4 M HNO3) and temperatures (25°C to 60°C). The macroscopic descr iption of the dissolution showed that the normalized dissolution rates wer e significantly increased for UO2 doped with PGM’s compared to pure UO2 used as reference compound. This effect was strengthened in less acid medi a. As instance\, a factor of 4500 was observed after 175 days of leaching in 0.1M HNO3. Simultaneously\, the dissolution of the pellets was followed in operando by ESEM. The combination of macroscopic and microscopic appro aches confirmed the modification of the preponderant mechanism occurring a t the solid/liquid interface from redox-controlled dissolution in strong n itric acid media to surface-controlled dissolution for less acidic media.\ n\n1. Martinez\, J. et al.\, J. Nucl. Mater.\, 462\, 173-181\, 2015\n2. Ma rtinez\, J. et al.\, J. Europ. Ceram. Soc.\, 35\, 4535-4546\, 2015\n\nhttp s://events01.synchrotron.org.au/event/51/contributions/1167/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1167/ END:VEVENT BEGIN:VEVENT SUMMARY:Alkali tin silicate glass as a wasteform for the immobilisation of plutonium DTSTART;VALUE=DATE-TIME:20171031T024500Z DTEND;VALUE=DATE-TIME:20171031T030000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1166@events01.synchrotron.org.au DESCRIPTION:Speakers: Amber Mason (University of Sheffield)\nUK stocks of separated civil plutonium are projected to exceed 140 tons at the end of r eprocessing. This material may require immobilisation in a proliferation resistant wasteform\, should it prove uneconomic to recycle in MOX fuel. We have investigated and optimised alkali tin silicate glass compositions for the immobilisation of this stockpile using CeO2 as a PuO2 surrogate. A remarkable two-fold increase in Ce solubility was achieved by in-situ re duction of CeO2 to Ce2O3\, as demonstrated by Ce L3 XANES\, through additi on of zero valent iron\, which also assisted in reducing the processing te mperature. Preliminary investigation showed this approach to be compatibl e with Hot Isostatic Pressing\, enabling batchwise processing of alkali ti n silicate glasses\, which is advantageous from fissile material accountan cy and criticality considerations. This work demonstrates the feasibility of an alternative and simple approach to conditioning the plutonium stock pile\, through hot isostatic pressing of a full glass wasteform\, potentia lly compatible with the full envelope of plutonium feedstock.\n\nhttps://e vents01.synchrotron.org.au/event/51/contributions/1166/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1166/ END:VEVENT BEGIN:VEVENT SUMMARY:Best Practice in the Management of Site Investigations for Geologi cal Disposal Facilities DTSTART;VALUE=DATE-TIME:20171102T044500Z DTEND;VALUE=DATE-TIME:20171102T050000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1164@events01.synchrotron.org.au DESCRIPTION:Speakers: Paul Degnan (Catalystra)\nThe disposal of intermedia te- and high-level radioactive waste requires emplacement in suitably engi neered underground facilities in order to ensure an adequate level of isol ation and containment for safety and security. We now have several example s of radioactive waste management organisations who have designed and unde rtaken extensive multi-disciplinary site investigation projects to charact erise environments for waste disposal in geological formations. However\, many countries requiring such facilities are still to initiate their own i nvestigations. It is therefore timely to compile lessons learnt on the man agement of site investigations for geological disposal facilities in order to support the sharing of knowledge and provide a platform for well-plann ed investigations to be undertaken in the future. Consequently\, this pres entation identifies important considerations associated with the planning and implementation of requirements-driven site investigation projects for geological radioactive waste disposal facilities.\n\nhttps://events01.sync hrotron.org.au/event/51/contributions/1164/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1164/ END:VEVENT BEGIN:VEVENT SUMMARY:Highly porous and stable metal–organic frameworks for uranium ex traction DTSTART;VALUE=DATE-TIME:20171101T221500Z DTEND;VALUE=DATE-TIME:20171101T223000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1163@events01.synchrotron.org.au DESCRIPTION:Speakers: Michael Carboni (CEA)\nTransformative technologies a re needed in order to achieve economic uranium extraction from waste to ge nerate a new fuel or for a safe storage. Metal–organic frameworks (MOFs) are a class of hybrid materials composed of organic bridging ligands coor dinated to metal ions or metal ion clusters. The result is the formation o f a porous crystalline solid that possess adequate stability in aqueous so lution for potential application in U extraction. These materials can sele ctively precipitate with a specific metal to extract it or they have large pore apertures to facilitate the transport of hydrated actinide\nions thr ough the interior of the frameworks for the extraction. In this way pollut ants such as actinides can be targeted for selective precipitation as a MO F or bind inside the framework by the ligand. This material can be easily recovered by simple filtration or centrifugation and actinide can be store d after a thermal treatment of the material to finally generate an origina l strategy to combine extraction and storage.\n\nhttps://events01.synchrot ron.org.au/event/51/contributions/1163/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1163/ END:VEVENT BEGIN:VEVENT SUMMARY:Structural incorporation of Cm3+ and Pu3+ in phosphate ceramics wi th monazite structure. DTSTART;VALUE=DATE-TIME:20171101T003000Z DTEND;VALUE=DATE-TIME:20171101T004500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1162@events01.synchrotron.org.au DESCRIPTION:Speakers: Stefan Neumeier (Forschungszentrum Jülich GmbH\, In stitute of Energy and Climate Research - IEK-6: Nuclear Waste Management a nd Reactor Safety\, 52425 Jülich\, Germany)\nPhosphate ceramics with mona zite structure are considered as potential waste forms for the conditionin g of specific nuclear waste streams (e.g. minor actinides and plutonium) d ue to their outstanding properties. In this study\, the incorporation of a ctinides (Cm3+ and Pu3+) into the monazite structure has been investigated combining X-ray diffraction (XRD) as well as X-ray absorption- (XAS) and time-resolved laser fluorescence spectroscopy (TRLFS). \nThe results demon strate the incorporation of the actinides on defined lanthanide lattice si tes in the monazite ceramics. From TRLFS measurements of Cm-doped (50 ppm) (La\,Gd)PO4 solid solutions\, a decrease of short-range order for the sol id solution compositions was observed in comparison to the end-members. Ad ditionally\, XAS investigations on pure-phase La1-xPuxPO4 (x = 0.01 – 0. 15) solid solutions verify the incorporation of plutonium in the +III oxid ation state in the monazites. The results provide a refined structural ins ight into mechanisms of actinide incorporation into monazite ceramics and solid solution formation.\n\nhttps://events01.synchrotron.org.au/event/51/ contributions/1162/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1162/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigation of C-14 in the CRUD collected on the coolant filter for safety disposal of radioactive waste containing C-14 (I)- C-14 release behavior and thermal decomposition characteristics of crud particles coll ected from the coolant filter of commercial PWR - DTSTART;VALUE=DATE-TIME:20171102T001500Z DTEND;VALUE=DATE-TIME:20171102T003000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1161@events01.synchrotron.org.au DESCRIPTION:Speakers: Kenichiro Kino (Nucler Development Corporation)\nIn the safety assessment of radioactive waste repository\, it is important to evaluate the migration behavior of long half-life radionuclides in the di sposal environment. It was reported that insoluble C-14 was generated in P WR. However\, the knowledge about the chemical form of C-14 is little.\nIn this study\, particles including C-14 collected from the coolant filters in PWR were analyzed by TG/MS to identify the chemical forms of these part icles. In addition\, C-14 in released gases and the residue in TG measurem ents were also investigated.\nResultantly\, it was revealed that fragments which were considered to be organic compounds derived from the ion-exchan ge resin were detected from the released gas\, and that majority(>90%) of C-14 inventory were detected in the residue after the inert gas heating.\n While the chemical forms of C-14 in the residue are not clarified\, it is suggested that insoluble C-14 may exist in the thermo-stable compounds.\n\ nhttps://events01.synchrotron.org.au/event/51/contributions/1161/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1161/ END:VEVENT BEGIN:VEVENT SUMMARY:Characterisation of the UK cement backfill material pre- and post- groundwater leaching experiments DTSTART;VALUE=DATE-TIME:20171102T030000Z DTEND;VALUE=DATE-TIME:20171102T031500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1158@events01.synchrotron.org.au DESCRIPTION:Speakers: Rita Vasconcelos (University of Sheffield)\nIn the U K\, the volume of intermediate level waste (ILW) requiring final disposal in a geological disposal facility\, is almost 450\,000 m3. In one of the U K conceptual scenarios for the geological disposal facility in a high-stre ngth crystalline rock\, the vaults will be backfilled with a cement-based material\, known as Nirex Reference Vault Backfill (NRVB). This material w ill provide a physical and chemical barrier to radionuclide release to the environment. Over the expected long lifetime performance of a cementitiou s backfill material\, NRVB will age and alter\, specifically due to intera ctions with groundwater. Understanding how these interactions will affect the properties of this material is of crucial importance for the developme nt of a robust safety case for the geological disposal facility. We here p resent the results of a detailed characterisation of NRVB pre- and post- g roundwater leaching experiments\, using three different types of groundwat er (granitic\, clay and saline groundwater)\, as analysed using convention al and advanced (e.g. tomography\, synchrotron XRD) techniques.\n\nhttps:/ /events01.synchrotron.org.au/event/51/contributions/1158/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1158/ END:VEVENT BEGIN:VEVENT SUMMARY:Application of Nuclear Waste Management and Remediation Experience and Lessons Learned DTSTART;VALUE=DATE-TIME:20171030T224500Z DTEND;VALUE=DATE-TIME:20171030T230000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1157@events01.synchrotron.org.au DESCRIPTION:Speakers: Jeanne Poling (CH2M)\n***Applying Successful Global Programs to the International Nuclear Decommissioning Market***\n\nCH2M ha s successfully managed waste management\, remediation and nuclear decommis sioning programs incorporating both innovations and lessons learned that h ave broad applicability to upcoming major decommissioning programs through out Australia and globally. \n\nThis abstract presents an international p erspective\, from CH2M\, on the importance of establishing an integrated w aste management strategy with the decommissioning program to better suppor t the waste generating projects in minimizing the amount of waste generate d and more effectively comply with regulatory waste acceptance criteria. T he overall success of a nuclear decommissioning program can be dependent o n accurate waste volume projection\; waste disposal pathway identification and integration\; waste treatment options identification\; waste characte rization\, treatment\, packaging and transportation\; and waste disposal ( including low-level disposal cell operations). An integrated Waste Managem ent Strategy is integrated with the decommissioning and demolition activit ies\; nuclear material management and disposition\; waste retrieval\, trea tment and disposal\; and environmental remediation activities.\n\nhttps:// events01.synchrotron.org.au/event/51/contributions/1157/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1157/ END:VEVENT BEGIN:VEVENT SUMMARY:The Need for Integrating the Back End of the Nuclear Fuel Cycle DTSTART;VALUE=DATE-TIME:20171030T004500Z DTEND;VALUE=DATE-TIME:20171030T011500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1156@events01.synchrotron.org.au DESCRIPTION:Speakers: Evaristo J. Bonano (Sandia National Laboratories)\nT he recognition that the endpoint of spent fuel management practices will b e deep geologic disposal of radioactive wastes leads to questions about ho w alternative options for spent nuclear fuel (SNF) management might affect performance of a geologic repository. Do some options for SNF management simplify the siting and design of a geologic repository? Do some geolog ic disposal concepts favor specific SNF management practices? Do some SNF management options favor specific geologic disposal concepts? Are some waste forms inherently preferable than others for geologic disposal? Give n the historical difficulty in many nations associated with siting and lic ensing geologic repositories for permanent disposal of SNF and high-level radioactive waste (HLW)\, are there activities that the spent fuel managem ent community could or should undertake today to facilitate future disposa l operations?\n\nLong-term repository safety is\, in general\, independent of specific treatments of SNF or HLW other that its packaging. However\, multiple aspects of the form in which the waste will be disposed are rele vant to repository design and performance\, including waste volume\, radio nuclide content\, thermal power\, waste package size\, and waste form and package lifetime in a range of geologic environments. Consideration of how these factors impact repository performance suggests that choices made now regarding SNF management may affect future flexibility in repository siting and design.\n\nIn the U.S.\, due to the absence of a final disposal site (since the suspension of the Yucca Mountain Project in 2009)\, nucle ar utilities have been storing SNF at their nuclear reactor sites using du al-purpose casks. These casks are large and\, depending on the burn-up of the SNF contained therein\, can also be very hot. This current practice can have significant implications for transportation and\, ultimately\, di sposal. This paper shall discuss these implications based on the current U.S. practice and will suggests ways in which these implications can be ad dressed.\nThe principal message that we intend to convey is the need for c areful planning while implementing upfront and temporary SNF management pr actices because of their potential costly implications to transportation a nd disposal. An integrated view of the entire back end of the nuclear fue l cycle (interim storage\, transportation\, and disposal) upfront during t he planning phases is paramount to develop and implement an effective SNF management program. \n\nSandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of S andia\, LLC\, a wholly owned subsidiary of Honeywell International\, Inc.\ , for the U.S. Department of Energy’s National Nuclear Security Administ ration under contract DE-NA-0003525. This abstract is Sandia publication 2017-5723A.\n\nhttps://events01.synchrotron.org.au/event/51/contributions/ 1156/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1156/ END:VEVENT BEGIN:VEVENT SUMMARY:Activation energy for parabolic corrosion kinetics of Zircaloy-4 b y consecutive hydrogen measurement at 30 – 80℃ DTSTART;VALUE=DATE-TIME:20171030T064500Z DTEND;VALUE=DATE-TIME:20171030T070000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1155@events01.synchrotron.org.au DESCRIPTION:Speakers: Tomofumi Sakuragi (Radioactive Waste Management Fund ing and Research Center)\nOn the issue related on a safe disposal of spent fuel claddings is the corrosion and the subsequent gas and radionuclides release. The Zircaloy corrosion under a prospected disposal condition has recently been investigated by sensitive hydrogen measurements at 30℃\, a nd reported that the kinetics in the rate around nm/y follows the paraboli c rate law.\nIn the present work\, an improved equipment to be usable even at higher temperatures up to 80℃ has been applied for measuring hydroge n gas generated from Zricaloy-4 corrosion for 90 days. The Arrhenius relat ion of the parabolic rate constants for the corrosion kinetics has showed the activation energy of 84.4 ± 8.4 kJ/mol\, the value of which is lower than that for the general pre-transition corrosion under the in-pile tempe rature above 260℃ (i.e. 113-135 kJ/mol)\, suggesting that simple mass tr ansfer through a thin and firm oxide film is limiting the low temperature corrosion of Zircaloy.\n\nhttps://events01.synchrotron.org.au/event/51/con tributions/1155/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1155/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigation of C-14 in the CRUD collected on the coolant filter for safety disposal of radioactive waste containing C-14 (II) –Chemical alternation of ion exchange resin under simulated condition in primary coo lant of PWR – DTSTART;VALUE=DATE-TIME:20171102T003000Z DTEND;VALUE=DATE-TIME:20171102T004500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1153@events01.synchrotron.org.au DESCRIPTION:Speakers: Kotaro Nakata (CRIEPI)\nRadiocarbon (C-14) is recogn ized as a radionuclide that includes significant impact on public exposure in safety assessment of radioactive waste disposal. Its origin\, generati on mechanism and chemical forms in the wastes are required to be understoo d for the reasonable and proper safety assessment of the radioactive waste disposal. Some previous studies have reported occurrence of insoluble C-1 4 in PWR\, and suggested that ion-exchange resin could be its origin. Howe ver\, this hypothesis has not been well evidenced yet\, because informatio n about the generation mechanism and chemical form of the insoluble C-14 i s still limited.\nIn this study\, alternation of the resin under heating a nd/or irradiation was investigated to understand the alternation of the re sin in PWR. In addition\, characteristics of CRUD on a coolant filter for the actual PWR were compared to those of the heated/irradiated resin. The results suggested that the insoluble C-14 arises from alternation of the i on-exchange resin.\n\nhttps://events01.synchrotron.org.au/event/51/contrib utions/1153/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1153/ END:VEVENT BEGIN:VEVENT SUMMARY:Radionuclide Sorption Behaviour on Fresh and Aged Cementitious Mat erials: A Comprehensive Database with 25 Elements DTSTART;VALUE=DATE-TIME:20171031T061500Z DTEND;VALUE=DATE-TIME:20171031T063000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1152@events01.synchrotron.org.au DESCRIPTION:Speakers: Dirk Mallants (CSIRO)\nCementitious materials are be ing widely used as solidification/stabilisation and barrier materials for a variety of radioactive wastes. The retention properties result from mine ral phases in hydrated cement that (i) possess a high density and diversit y of reactive sites for the fixation of radionuclides through a variety of sorption reactions (surface adsorption\, incorporation and solid-solution formation)\, and (ii) buffer pH in the range 10–13. A quantitative data base on the solid/liquid distribution behaviour (“sorption database”) of 25 elements (Ag\, Am\, Be\, C\, Ca\, Cl\, Cs\, H\, I\, Mo\, Nb\, Ni\, N p\, Pa\, Pb\, Pd\, Pu\, Ra\, Se\, Sn\, Sr\, Tc\, Th\, U\, Zr) in hydrated cement systems is established on the basis of a consistent review and re-e valuation of literature data. Effects of geochemical evolution or ageing c ements on sorption/incorporation processes are explicitly evaluated and qu antified. In addition to recommended values\, all underlying original expe rimental data and key experimental information are provided.\n\nhttps://ev ents01.synchrotron.org.au/event/51/contributions/1152/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1152/ END:VEVENT BEGIN:VEVENT SUMMARY:Management of the Radioactive Waste arising from the Decommissioni ng of the WWR-S Research Reactor from IFIN-HH\, Magurele\, Romania DTSTART;VALUE=DATE-TIME:20171030T230000Z DTEND;VALUE=DATE-TIME:20171030T231500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1151@events01.synchrotron.org.au DESCRIPTION:Speakers: Cristian Dragolici (IFIN-HH)\nThe WWR-S research rea ctor from National Institute for R&D in Physics and Nuclear Engineering Ho ria Hulubei (IFIN-HH)\, Magurele site\, Romania\, is currently in the year 2 of the phase 3 of the decommissioning project. Big components are cut i n small parts to reduce the size for a proper packing and temporary dispos al. Segregation is used to separate different type of materials depending on their physical and chemical properties. After that\, the radioactive wa ste is accommodated in a standard barrel (220L) and send to radiological c haracterization laboratory before its arrival to the Waste Treatment Plant . High activated/contaminated materials are stored in shielded containers. \nIn Romania\, all the radioactive waste coming from decommissioning of th e research reactor is treated and packed at the Radioactive Waste Manageme nt Department (RWMD) and sent for final disposal at the National Radioacti ve Waste Repository (NRWR) in Baita\, Bihor County.\n\nhttps://events01.sy nchrotron.org.au/event/51/contributions/1151/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1151/ END:VEVENT BEGIN:VEVENT SUMMARY:Chornobyl NPP Cooling Pond: Decommissioning DTSTART;VALUE=DATE-TIME:20171030T223000Z DTEND;VALUE=DATE-TIME:20171030T224500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1150@events01.synchrotron.org.au DESCRIPTION:Speakers: Oleksandr Novikov (SSE Chernobyl NPP)\nThe Cooling P ond of Chornobyl NPP (hereinafter referred to as CP) was formed by constru cting an embankment on the flood plain of the Prypiat River\, its area mad e about 22.9 km2\; its water volume making 151 million m3 was calculated f or cooling Chornobyl NPP four units in mode of electric power generation.\ nWhen CP was operated the water level was maintained up to the design leve l which made 111m of BHS (meters as per the Baltic height system).\nThe av erage annual water level in CP within its operation was 7 meters higher th an the water level in the Prypiat River.\nThe special feature of the Cooli ng Pond is its location within the area of Exclusion Zone and Absolute (Ob ligatory) Resettlement Zone - the area which was radioactively contaminate d resulting from Chornobyl NPP Unit 4 accident in 1986.\nDue to the reduct ion of cooling water demand after termination of the electric power genera tion such a facility is not required any more and now its decommissioning programme is implemented.\nThe Cooling Pond decommissioning activities cov er radiation and ecological monitoring\, namely:\n- radiation condition in the surface layer of the atmosphere\;\n- exposure dose rate within the dry sections of the Cooling Pond\;\n- radionuclide content in groun dwater\;\n- water level\, radiological and chemical changes of the Cool ing Pond water\;\n- the changes of the hydrobiological condition and ge obotanical changes.\nThe presentation demonstrates the results of radiatio n and ecological monitoring.\n\nhttps://events01.synchrotron.org.au/event/ 51/contributions/1150/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1150/ END:VEVENT BEGIN:VEVENT SUMMARY:P-31 Nuclear Magnetic Resonance as a Probe of Plutonium Incorporat ion and Radiation Damage in Phosphates DTSTART;VALUE=DATE-TIME:20171031T044500Z DTEND;VALUE=DATE-TIME:20171031T050000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1149@events01.synchrotron.org.au DESCRIPTION:Speakers: Ian Farnan (University of Cambridge)\nPlutonium dope d YPO4 was prepared to test the extent of solid solution and the effect of radiation damage over several years. Y0.92 238Pu0.08PO4 showed the presen ce of a Pu substituted xenotime phase and a 238PuP2O7 phase by X-ray diffr action (XRD). The 31P magic‑angle spinning nuclear magnetic resonance ( MASNMR) spectrum showed peaks for PuP2O7 and peaks assigned to phosphorus coupled to Pu3+ substituted randomly into Y3+ sites. A time series of 31P MASNMR and XRD measurements observed the loss of the reflections due to th e 238PuP2O7 phase in the XRD pattern of the Y0.92238Pu0.08PO4 sample withi n 4 weeks. The MASNMR spectra obtained at longer times in both the Y0.92 238Pu0.08PO4 and Y0.96 238Pu0.04PO4 samples showed an additional broadened and shifted 31P resonance assigned to amorphised xenotime with a chemical shift consistent with Q0 orthophosphate. Thus\, the amorphised local stru cture is assigned to a predominantly Q0 phosphate arrangement subject to l ocal densification.\n\nhttps://events01.synchrotron.org.au/event/51/contri butions/1149/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1149/ END:VEVENT BEGIN:VEVENT SUMMARY:A study to develop a new glass formulation for the immobilisation of HLW containing molybdenum and large amounts of sodium. DTSTART;VALUE=DATE-TIME:20171031T033000Z DTEND;VALUE=DATE-TIME:20171031T034500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1146@events01.synchrotron.org.au DESCRIPTION:Speakers: Clive Brigden (ISL\, Department of Materials Science & Engineering\, University of Sheffield\, S1 3JD\, UK.)\nA study to devel op a new high level waste (HLW) glass formulation for waste from the highl y active liquor storage (HAL) tanks at Sellafield is described. A likely washout scenario for the tanks at the end of operations involves the use o f sodium carbonate as a tank washout reagent [1] leading to a high soda wa stestream. Titanium is not currently used in existing HLW formulations in European nuclear waste glasses\, however\, literature suggests that titano silicate glasses can accommodate large amounts of sodium [2-4]\, even up t o 50 mol% [5]. Following a combinatorial type approach exploring the eff ects of variation of alumina (Al2O3)\, boron oxide (B2O3)\, calcium and mi xed alkali content in sodium titanosilicate formulations with and without waste simulant (including molybdenum and zirconium oxides) and durability assessment\, two promising formulations are currently being trialled and f ull product waste simulant containing glass being prepared via base glass frit plus waste simulant combination. Further durability trials and struc tural characterisation are also being investigated and results will be rep orted.\n \n1 M. J. Edmondson et al.\, "A Methodology for Post O perational Clean Out of a Highly Active Facility Including Solids Behaviou r"\, 12386\, 2012 (Submitted for the WM2012 Conference\, Phoenix\, Arizona \, USA).\n2 Hamilton\, E. H. and G. W. Cleek (1958). "Properties of so dium titanium silicate glasses” J. Res. Nat. Bur. Standards. 61 (2) 89-9 4.\n3 Turnbull\, R. C. and W. G. Lawrence (1952). "The role of titania in silica glasses” J. Amer. Ceram. Soc. 35 (2) 48-53.\n4 Strimple\, J. H. and E. A. Giess (1958). "Glass formation and properties of glasses in the system Na2O-B2O3-SiO2-TiO2" J. Amer. Ceram. Soc. 41 (7) 231-237.\n5 Washburn\, E. W. and E. N. Bunting (1934). "Note on phase equilibria in the system Na2O-TiO2." J. Res. Nat. Bur. Standards 12 (2) 239-239.\n\nT his document has been prepared by Clive Brigden as part of collaborative p roject involving Sellafield Ltd. Some of the information it contains is ow ned by Sellafield Ltd or NDA and is\, or may be\, proprietary or subject t o restrictions relating to national security\, commercial or personal obli gations. It is submitted to Scientific Basis for Nuclear Waste Management 2017 meeting for the purposes of professional assessment. It may be copied and distributed as required for this purpose but no other use may be made of any component owned by Sellafield Ltd or NDA without the prior permiss ion of Sellafield Ltd.\n\nhttps://events01.synchrotron.org.au/event/51/con tributions/1146/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1146/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigating Local Defect Structures in Nuclear Waste Form Materi als DTSTART;VALUE=DATE-TIME:20171031T041500Z DTEND;VALUE=DATE-TIME:20171031T044500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1145@events01.synchrotron.org.au DESCRIPTION:Speakers: Maik Lang (University of Tennessee)\nFor the past 30 years\, the development of durable materials for radionuclide immobilizat ion has been central to efforts to dispose of wastes generated by the nucl ear fuel cycle. There still exist\, however\, large gaps in the understand ing of fundamental modes of waste form degradation under repository condit ions. Comprehensive evaluation of waste form performance\, including resis tance to corrosion\, requires detailed knowledge of the atomic-scale effec ts of long-term self-irradiation. We have recently shown that pair distrib ution function (PDF) analysis of neutron total scattering measurements can be applied to uniquely characterize radiation effects in a wide range of waste form materials\, including fluorite-derivative pyrochlores\, actinid e oxides\, and glasses. These measurements allow a detailed analysis of bo th cation and anion defect behavior\, and short range order and disorder\, which is particularly important for the investigation of aperiodic glasse s. Recent results have shown complex disordering in pyrochlores\, and oxyg en defect clustering in actinide oxides.\n\nhttps://events01.synchrotron.o rg.au/event/51/contributions/1145/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1145/ END:VEVENT BEGIN:VEVENT SUMMARY:Ion Beam Irradiation of Ceramic-glass Waste Form at ANSTO DTSTART;VALUE=DATE-TIME:20171031T053000Z DTEND;VALUE=DATE-TIME:20171031T054500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1144@events01.synchrotron.org.au DESCRIPTION:Speakers: Tao Wei (ANSTO)\nRadioactive wastes are generated fr om the entire nuclear fuel cycle from mining to the burning of uranium fue l in the nuclear reactors. Pyrochlore (ABTi2O7) and zirconolite (CaZrTiO7) based glass-ceramics have been became an immerging candidate waste form m atrix and attracted attention as it combines the process and chemical flex ibility of glasses with the chemical durability of ceramics. It also has a potential ability to immobilize some compositionally diverse actinide-ric h radioactive wastes\, e.g. plutonium residue wastes and separated minor a ctinides. The efforts to evaluate the radiation resistance of the glass-ce ramic waste form by ion beam irradiation have been undertaken using accele rators at ANSTO. This paper reported ANSTO’s capability and development in this area and gave the results of the irradiation-induced structure mod ification in the glass-ceramics irradiated by helium and gold ions.\n\nhtt ps://events01.synchrotron.org.au/event/51/contributions/1144/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1144/ END:VEVENT BEGIN:VEVENT SUMMARY:Quantification of irradiation induced structural disorder in nucle ar waste-form ceramics with µ-luminescence spectroscopy of lanthanides DTSTART;VALUE=DATE-TIME:20171031T051500Z DTEND;VALUE=DATE-TIME:20171031T053000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1143@events01.synchrotron.org.au DESCRIPTION:Speakers: Christoph Lenz (ANSTO)\nThe investigation of radiati on damaged or metamict minerals and their synthetic analogues has increase d appreciably over the past two decades\, stimulated by the potential use of mineral-like ceramics as waste forms for the immobilisation of reproces sed spent nuclear fuel and other radioactive waste. In this research field \, however\, a fast and inexpensive technique operating in the micrometre range may open up new opportunities in the characterisation of radiation d amage.\n\nWe present first results of a heavy-ion (Au) irradiation-study o f the important nuclear waste-form matrices zircon (ZrSiO4)\, xenotime-(Y) (YPO4) and zirconolite (CaZrTi2O7). Bulk\, poly-crystalline ceramics were irradiated with accelerated heavy ions (Au) with energies up to 35 MeV. C omparably high heavy-ion energies are chosen to ensure irradiation penetra tion-depths of 4 - 5 µm accessible to the spatial resolution of optical c onfocal spectrometers.\n\nhttps://events01.synchrotron.org.au/event/51/con tributions/1143/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1143/ END:VEVENT BEGIN:VEVENT SUMMARY:Multinational Waste Repositories: A South Australian Initiative DTSTART;VALUE=DATE-TIME:20171030T014500Z DTEND;VALUE=DATE-TIME:20171030T020000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1142@events01.synchrotron.org.au DESCRIPTION:Speakers: Massey de los Reyes (South Australian Environment Pr otection Authoirty)\nOn the 19th of March 2015\, the Nuclear Fuel Cycle Ro yal Commission (NFCRC) was established by the South Australian Government\ , and tasked to undertake an independent examination into the opportunitie s and risks for South Australia’s further involvement in the Nuclear Fue l Cycle. This presentation will review the process\, findings and recommen dations delivered by the NFCRC\, with particular emphasis on the proposed opportunity for the storage and disposal of international high-level and i ntermediate-level waste in South Australia and the potential value-add tha t this could provide on a global scale.\nOutcomes of the State-wide 'KnowN uclear' community consultation program will also be discussed\, as well as the possible next steps needed in advancing the South Australian multinat ional repository concept forward.\n\nhttps://events01.synchrotron.org.au/e vent/51/contributions/1142/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1142/ END:VEVENT BEGIN:VEVENT SUMMARY:Partitioning of Ce\, as a Simulant for Pu\, in a Multiphase Cerami c Nuclear Waste Form DTSTART;VALUE=DATE-TIME:20171031T224500Z DTEND;VALUE=DATE-TIME:20171031T230000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1140@events01.synchrotron.org.au DESCRIPTION:Speakers: Zhaoming Zhang (ANSTO)\nA multi-phase titanate waste form was synthesized using high temperature sintering in air or Ar with t he composition of Ca0.71Y0.088Ce0.52Hf0.22Ti2Ox. The phase assemblage was investigated as a function of the sintering atmosphere. X-ray diffraction measurements indicated that oxidizing sintering atmosphere (air) favors th e formation of pyrochlore\, whereas neutral environment (Ar) promotes the formation of perovskite\, although both sintering atmospheres produced sam ples containing three phases (pyrochlore\, perovskite and rutile under air or zirconolite\, perovskite and rutile under Ar). Scanning electron micro scope (SEM) analysis revealed that Ce is present in perovskite and pyrochl ore (or zirconolite)\, but not in rutile. Micro-X-ray-Absorption-Near-Edge -Structure (micro-XANES) measurements conducted at the Ce L-edge\, in comb ination with electron energy loss spectroscopy (EELS)\, showed that Ce4+ p refers to inhabit the pyrochlore (or zirconolite) phase and Ce3+ the perov skite phase. This knowledge is valuable for the further development of ti tanate waste forms to immobilize Pu.\n\nhttps://events01.synchrotron.org.a u/event/51/contributions/1140/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1140/ END:VEVENT BEGIN:VEVENT SUMMARY:Current advances on titanate-based glass-ceramics for actinide imm obilization DTSTART;VALUE=DATE-TIME:20171101T024500Z DTEND;VALUE=DATE-TIME:20171101T030000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1139@events01.synchrotron.org.au DESCRIPTION:Speakers: Yingjie Zhang (ANSTO)\nGlass-ceramics have attracted recent attention as they have the advantage of combining the chemical fle xibility of glasses with the excellent durability of ceramics\, making the m potential waste forms for the immobilization of actinide wastes with pro cessing chemicals. Glass-ceramics based on titanate ceramic phases\, e.g. zirconolite\, pyrochlore and brannerite have been developed at ANSTO. The formations of these titanate dominated glass-ceramics have been demonstrat ed with uranium as proof of concept and plutonium with gadolinium and/or h afnium as neutron absorbers. This talk will focus on the current advances in the field including the formation and crystallization of titanate phase s in glass\, structure and microstructure characterization\, actinide inco rporation and actinide valences.\n\nhttps://events01.synchrotron.org.au/ev ent/51/contributions/1139/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1139/ END:VEVENT BEGIN:VEVENT SUMMARY:Tc reduction by bacteria from soda lake DTSTART;VALUE=DATE-TIME:20171102T053000Z DTEND;VALUE=DATE-TIME:20171102T054500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1138@events01.synchrotron.org.au DESCRIPTION:Speakers: Konstantin German (A.N.Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences)\nOne of th e problematic types of LRW are alkaline wastes generated in some types of spent\nnuclear fuel reprocessing. Environmental friendly biological techni ques of LRW treatment\nare not widespread because of its extremely high sa lt contents and alkalinity usually not\nsuitable for organisms. The aim of this work was to explore the use of microorganisms\nfrom extremely alkali ne habitat to process liquid alkaline radioactive waste. This involved a\n search of promising microbial cultures from extremely alkaline lakes of th e Kulunda steppe\,\nwhich composition is close to alkaline wastes. The lak e sediments with medium (44-85 g/L)\nand extremely high (300-400 g/L) salt content were selected for investigations\; the microbial\nassociations\, which capable to reduce radionuclides were received. Experiments on reduct ion\nof technetium and uranyl acetate + pertechnetate were performed. The bacteria present in\nthe sediments and sludge of soda lakes reduced pertec hnetate ions in both experiments with\nhigh salinity (2.3 M - 84% techneti um reduced) and in experiment with a lower salinity (0.8\nM - 86% techneti um reduced) wherein uranium had no competitive effect on the recovery of\n technetium - in experiments with 1) technetium and 2) with technetium + ur anyl acetate\nreduced approx. 84% of pertechnetate. When using the mixed s ludge from lower salt content\nlake the amount of reduced technetium was l ower compared to the high salinity - 55-60%.\nThis work was supported by R FBR grant 15-05-08919\n\nhttps://events01.synchrotron.org.au/event/51/cont ributions/1138/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1138/ END:VEVENT BEGIN:VEVENT SUMMARY:U-rich ceramics for Spent Fuel or Acidic 99Mo Production ILW DTSTART;VALUE=DATE-TIME:20171101T023000Z DTEND;VALUE=DATE-TIME:20171101T024500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1137@events01.synchrotron.org.au DESCRIPTION:Speakers: Eric R Vance (ANSTO)\nSpent fuel has long been unoff icially classified as HLW which is cooled for a few years to allow the dis sipation of short-lived fission products and then is to be contained in th ick-walled Cu or carbon steel containers for deep repository disposal wher e it is argued that the containers will perform immobilisation for ~105 yr . However immobilisation assumes highly reducing conditions in which UO2 i s essentially unreactive and even water-soluble fission products will be c ontained. The only published engineered waste form for spent UO2 fuel is s ynroc-F in which the U concentration is nearly 50 wt.% and the fission pro ducts are incorporated in resistate titanate mineral phases. We have tried to extend this concept by hot isostatic pressing glass-ceramics in which synroc-F constitutes the ceramic phase and the glass furnishes a second ph ase for fission product immobilisation and increases the general reactivit y. We have also used the same approach for acidic 99Mo production ILW.\n\n https://events01.synchrotron.org.au/event/51/contributions/1137/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1137/ END:VEVENT BEGIN:VEVENT SUMMARY:Alkali technetium oxides and their relation to Tc loading in nucle ar waste glasses DTSTART;VALUE=DATE-TIME:20171102T051500Z DTEND;VALUE=DATE-TIME:20171102T053000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1136@events01.synchrotron.org.au DESCRIPTION:Speakers: John McCloy (Washington State University)\nBecause o f their radioactive nature\, solid technetium-99 oxides have been rarely s tudied\, and there is\na dearth of modern spectra and diffraction patterns in the literature. This publication aims to address\nthis by detailing a low-temperature synthesis method for pure\, crystalline alkali pertechneta tes\,\nalong with complete analysis by static and magic-angle-spinning nuc lear magnetic resonance\, Raman\,\nneutron diffraction (ND)\, and X-ray ab sorption spectroscopy (XAS). Insight gained from these\nstudies brings a d eeper understanding of the periodic chemistry of alkali (Na\,K\,Rb\,Cs) pe rtechnetates.\nAdditionally\, we report attempts to make 5- and 6-coordina te pertechnetate compounds of K\, Na\,\nand Li\, i.e. TcO5 - and TcO6 -. I t was found that higher coordinated species are very sensitive to\nwater\, and easily decompose into their respective pertechnetates. It was difficu lt to obtain pure\ncompounds\, but mixtures of the pertechnetate and other phases were frequently found\, as evidenced\nby XAS\, ND\, and Raman spec troscopy. Additionally\, we summarize other work on Tc loading\nin glasses \, effect on glass structure\, and salt formation in overloaded samples. F or glasses\, XAS\nchemometrics based on principal component analysis and l inear combination fitting suggests that Tc\nis speciated first as isolated Tc4+\, as Tc content is increased\, there is more Tc7+ which partitions\n first to K neighbors then to isolated sites. Preliminary work is reported assessing HTcO4 and related\ncompounds and their relationships to mechanis ms of Tc volatility\n\nhttps://events01.synchrotron.org.au/event/51/contri butions/1136/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1136/ END:VEVENT BEGIN:VEVENT SUMMARY:Comparison of thermal expansion of Tc and Re salts. DTSTART;VALUE=DATE-TIME:20171102T050000Z DTEND;VALUE=DATE-TIME:20171102T051500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1134@events01.synchrotron.org.au DESCRIPTION:Speakers: Gordon Thorogood (ANSTO)\n99Tc is the most significa nt long-lived product of uranium fission\, producing the largest fraction of the total long-lived radiation emissions of nuclear waste. Tc 7+ compo unds are highly mobile in the environment. Relatively little is known reg arding the solid state chemistry of Tc. Recently we studied the structural properties of (NH4)TcO4 (Tc7+) and confirmed that this is isostructural w ith (NH4)ReO4 adopting a tetragonal scheelite type structure in space grou p I41/a. The unit cell parameters of (NH4)TcO4 are strongly temperature d ependent with the structure showing negative thermal expansion along both the a- and c-axis\, albeit at different temperatures This behavior is sig nificantly different to that previously reported for the isostructural oxi de (NH4)ReO4\, although we note that the data for (NH4)ReO4 was collected at much lower resolution. Nevertheless it is clear in the literature that the thermal expansion behavior of (NH4)ReO4 is highly anisotropic. Despi te the difference in the thermal expansion between what we have observed f or (NH4)TcO4 and that described by others for (NH4)ReO4 it is likely that the origin of the anomalous thermal expansion in is the same in both cases \, namely it is a consequence of re-orientation of the ammonium ions in th e surrounding cage of eight oxygen atoms. To verify this for (NH4)TcO4 re quires we replace the ammonium cation with another small cation. Therefor e we have compared the thermal behavior of AReO4 with ATcO4 to determine i f Re oxides are suitable surrogates to predict the behavior of Tc oxides a nd how they may behave in the environment.\n\nhttps://events01.synchrotron .org.au/event/51/contributions/1134/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1134/ END:VEVENT BEGIN:VEVENT SUMMARY:Unusual redox neighborhood in technetium compounds DTSTART;VALUE=DATE-TIME:20171102T054500Z DTEND;VALUE=DATE-TIME:20171102T060000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1133@events01.synchrotron.org.au DESCRIPTION:Speakers: Konstantin German (A.N.Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences)\nTechetium has a great number of oxidation states (usually we say 9 but in fact much \nmore) and is evidently one of the elements with the most complicated che mistry. This is\ndue its position in the center of 4d elements row with 7 electrones available for chemical\nbonding. One of the very special option s complicating technetium chemistry is its ability to\ncluster formation a nd especially the possibility for Tc cluster to be reduced by consequtive\ naddition of electrones one by one. So the oxidation states of Tc in hydro chloric acid could be\n4+ (in K2TcCl6)\, 3+ (in [Bu4N]2Tc2Cl8)\, 2.5+ (in K3Tc2Cl8)\, 2+ (in K2Tc2Cl6)\, 11/6+\n(in [Me4N]3Tc6Cl14 and 10/6+ (in [Me 4N]2Tc6Cl12). We could imagine the number of\nhydroxides that could be for med sturting from these compounds. Another option is the\npresence of Tc a toms in different oxidation states within the same compound (p.e. Tc2Ac42\ nwhere Tc3+ and Tc7+ coexist in the one compound. New example is the red p ertechnic acid.\nAccording to new synthesis and X ray structure study it c ontains 4 TcO6 octahedra with\nTc6+\, that is usually considered extremely unstable and 16 Tc(VII) tetrahedra aranged in a\njoint compund [TcVI 4TcV II 1668]·16H2O: a = 11.1743(6)\, b = 12.8839(6)\, c = 14.0661(6)\nÅ\, α = 71.128(2)\, β = 69.015(2)\, γ = 74.340(2)◦\n\, P-1\, Z = 1. Of next extreme interest is\nnew Pu(III)(DMSO)6[TcO4]3 compound where reducing an d oxidizing parts coexist.\n\nhttps://events01.synchrotron.org.au/event/51 /contributions/1133/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1133/ END:VEVENT BEGIN:VEVENT SUMMARY:Aqueous leaching of high burnup UO2 fuel under hydrogen conditions DTSTART;VALUE=DATE-TIME:20171030T043000Z DTEND;VALUE=DATE-TIME:20171030T044500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1132@events01.synchrotron.org.au DESCRIPTION:Speakers: Anders Puranen (Studsvik Nuclear)\nLeaching results on fragments of high burnup (65 MWd/kgU) UO2 fuel from a commercial pressu rized water reactor are presented. The experiments were performed in simpl ified granitic groundwater under a hydrogen pressure of up to 5 MPa\, repr esenting conditions in a water intrusion scenario for a Swedish KBS-3 desi gn spent nuclear fuel repository. The freshly crushed fragments were pre-w ashed under aerated conditions for 6 days to remove part of the instant re lease fraction of the radionuclide inventory and transferred to an autocla ve for leaching under hydrogen conditions. Following an initial release of U attributed to dissolution of oxidized phases from the aerated handling\ , the U concentration decreased to levels of 2-5x10-9 M\, in-line with the solubility of amorphous UO2. The release of radionuclides such as Cs and Sr gradually declined indicating a transition towards inhibition of the fu el matrix dissolution.\n\nhttps://events01.synchrotron.org.au/event/51/con tributions/1132/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1132/ END:VEVENT BEGIN:VEVENT SUMMARY:(Scholarship application) Thermal Treatment of Magnox Sludge Inter mediate Level Nuclear Waste through Vitrification DTSTART;VALUE=DATE-TIME:20171031T003000Z DTEND;VALUE=DATE-TIME:20171031T004500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1131@events01.synchrotron.org.au DESCRIPTION:Speakers: Sean Barlow (University of Sheffield)\nVitrification of sludge waste arising from legacy nuclear activities such as Magnox rep rocessing is a promising alternative to the current baseline plan of cemen tation with superior long-term durability\, improved waste loadings and si gnificant volume reduction. Glass products were produced from oxidized and metallic uranium and magnesium\, representative of the extremes found wit h the First Generation Magnox Storage Ponds\, in simple 3 or 4 component s ystems. \nMagnesium aluminosilicate (MAS) and magnesium borosilicate (MBS) glasses were analytically characterised by X-ray diffraction\, scanning e lectron microscopy\, differential thermal analysis\, X-ray absorption spec troscopy and inductively coupled plasma optical emission spectrometry. Acc elerated dissolution testing was performed at 90 °C for 28 days with peri odic sampling of the leachate solution. \nSurrogate materials neodymium an d the rare-earth alloy mischmetal were used alongside uranium and subject to the same testing regime to determine the effectiveness and validity of using such substitute materials in scientific studies of uranium bearing g lass.\n\nhttps://events01.synchrotron.org.au/event/51/contributions/1131/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1131/ END:VEVENT BEGIN:VEVENT SUMMARY:Solubility of the rhabdophane\, LnPO4.0.667 H2O (Ln = La to Dy): i mplications for the long-term stability of monazite matrices. DTSTART;VALUE=DATE-TIME:20171031T234500Z DTEND;VALUE=DATE-TIME:20171101T001500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1130@events01.synchrotron.org.au DESCRIPTION:Speakers: Stéphanie Szenknect (ICSM)\nMinerals belonging to t he monazite family\, REEPO4 (REE: Y\, Sc\, La to Dy) could incorporate in their structure substantial amounts of Th and U [1]. Moreover\, monazites maintain their crystallinity even after geological times of exposure to se lf-irradiation. Therefore\, this phase appears as a promising candidate fo r the specific conditioning of transuranic elements (AnIV\,AnIII). Already \, many thermodynamic properties of monazite are reported in the litteratu re [2]. However\, its hydrated form namely\, rhabdophane\, REEPO4.0.667 H2 O could be stabilized at low temperatures\, and thus control the concentra tions of actinides in solution after the leaching of the monazite matrices [3\, 4]. \n\nFor the first time\, a systematic study of the solubility of the rhabdophane\, LnPO4.0.667 H2O (Ln = La to Dy) was performed using ove r-saturated and under-saturated experiments at different temperatures (298 to 363 K) to demonstrate the reversibility of the solubility equilibrium [5]. The structure of the neoformed phases was carefully controlled in the entire range of temperatures in order to attribute unambiguously the solu bility products and the derived thermodynamic data associated to the rhabd ophane phases. The obtained results indicate that the stability domain of the rhabdophane phase is limited in temperature and depends on the ionic r adius of the lanthanide. The values of the solubility constant depend also slightly on the lanthanide with log KS\,0° (298 K) ranging from -25.6 ± 0.8 (Pr) to -24.9 ± 1.7 (Eu) with minimum values for Pr to Sm. The value s of the standard free enery of formation at 298 K varied between -1984 ± 2 and -2004 ± 2 kJ.mol-1 whatever the lanthanide element considered\, ex cept for Eu-rhabdophane that presented the highest value for the Gibbs ene rgy of formation (-1896 ± 2 kJ.mol-1).\nFrom the solubility data obtained at various temperatures\, the values of enthalpy of formation of the rhab dophanes were found between -2151 ± 13 and -2130 ± 12 kJ. mol-1 excepted for Eu for which it reached -2057 ± 9 kJ.mol-1. It is worth noting that the data reported by Ushakov et al. [6] for monazites LnPO4 (Ln = La to Gd ) determined by oxide melt calorimetry and recalculated by taking into acc ount the contribution of the water molecules are in very good agreement wi th the data obtained for rhabdophane in this work. This result indicates t hat the enthalpy of formation of the rhabdophane can be simply deduced fro m the enthalpy of formation of the monazite by adding the contribution of 0.667 molecule of structural water.\n\nThese results could be used to esti mate the thermodynamic properties of AnIIIPO4 .0.667 H2O (with AnIII =Am\, Pu or Cm) by analogy with the lanthanides of close ionic radii. The rhabd ophane structure can also incorporate AnIV by coupled substitution of LnII I by MII and AnIV. In this field\, Nd0.8Ca0.1Th0.1PO4 .n H2O were prepare d by wet chemistry route and preliminary solubility data were determined\, which showed that this phase is metastable in solution at 298 K\, Th and Nd being released leading to the formation of Th2(PO4)2(HPO4). H2O (TPHPH) [7] and NdPO4.0.667 H2O\, respectively.\n\nReferences:\n[1] N. Clavier\, R. Podor\, N. Dacheux\, (2011). Journal of the European Ceramic Society 31 : 941-976.\n[2] F. Poitrasson\, E. Oelkers\, J. Schott\, J.-M. Montel\, (2 004).Geochimica et Cosmochimica Acta 68: 2207-2221.\n[3] E. Du Fou de Kerd aniel\, N. Clavier\, N. Dacheux\, O. Terra\, R. Podor\, (2007). Journal of Nuclear Materials 362: 451-458.\n[4] N. Dacheux\, N. Clavier\, R. Podor\, (2013). American Mineralogist 98: 833-847.\n[5] C. Gausse\, S. Szenknect\ , D.W. Qin\, A. Mesbah\, N. Clavier\, S. Neumeier\, D. Bosbach\, N. Dacheu x\, (2016). European Journal of Inorganic Chemistry 2016: 4615-4630.\n[6] S.V. Ushakov\, K.B. Helean\, A. Navrotsky\, L.A. Boatner\, (2001). Journal of Materials Research 16: 2623-2633.\n[7] D. Qin\, C. Gausse\, S. Szenkne ct\, A. Mesbah\, N. Clavier\, N. Dacheux\, (2017). The Journal of Chemical Thermodynamics\, dx.doi.org/10.1016/j.jct.2017.01.003\n\nhttps://events01 .synchrotron.org.au/event/51/contributions/1130/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1130/ END:VEVENT BEGIN:VEVENT SUMMARY:Ion irradiation used as surrogate for neutron irradiation to under stand nuclear graphite evolution during reactor operation: consequences fo r the long lived radionuclide’s behavior DTSTART;VALUE=DATE-TIME:20171031T054500Z DTEND;VALUE=DATE-TIME:20171031T060000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1129@events01.synchrotron.org.au DESCRIPTION:Speakers: Nelly TOULHOAT (CNRS/IN2P3/IPNL)\nGraphite has been widely used in different types of reactors such as gas or water cooled rea ctors. Disposal of the irradiated graphite waste is a current management s trategy for the resulting graphite waste for which two main radionuclides\ , 14C and 36Cl\, might be dose determining at the outlet. In order to simu late both ballistic and electronic effects induced by irradiation\, model and nuclear graphite samples implanted with 37Cl or 14C (to simulate the r adionuclides) have been irradiated using ions by varying the Sn(nuclear)/S e(electronic) stopping power ratio. Extrapolating to reactor irradiation\, we show that depending on the initial graphite ordering level and texture (binder/grain) and according to the subsequent neutron flux and temperatu re\, graphite irradiation results into a structural “zoning” impacting the radionuclide behavior: except when located close to open pores\, 14C is stabilized into graphite whereas 36Cl’s release is strongly correlate d to the counteracting effects of irradiation and temperature.\n\nhttps:// events01.synchrotron.org.au/event/51/contributions/1129/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1129/ END:VEVENT BEGIN:VEVENT SUMMARY:Identification of chemical form of stable carbon released from typ e 304 and 316 stainless-steel powders in alkaline solution and in acidic s olution under low-oxygen condition DTSTART;VALUE=DATE-TIME:20171102T043000Z DTEND;VALUE=DATE-TIME:20171102T044500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1128@events01.synchrotron.org.au DESCRIPTION:Speakers: Ryo Nakabayashi (Central Research Institute of Elect ric Power Industry)\nThe chemical form of carbon-14 released from irradiat ed stainless steel is a key parameter in the safety assessment of the sub- surface disposal system in Japan. In this study\, unirradiated 304 and 316 stainless-steel powders were immersed in HCl solution and in NaOH solutio n under a low-oxygen condition to identify the chemical form of the releas ed carbon. The main chemical forms of the carbon were formic and acetic ac ids in the HCl solution and colloidal carbon in the NaOH solution. Point a nalysis of the colloidal particles by transmission electron microscopy equ ipped with energy dispersive spectroscopy showed that C was accompanied wi th Fe and Cr. Fe and Cr tended to precipitate thermodynamically as hydroxi des in an alkaline environment\, suggesting that carbon sorbed onto the hy droxide. Meanwhile\, in the HCl solution\, the hydroxides did not precipit ate thermodynamically\, so carbon appeared to be released as an ionic form without the formation of metallic hydroxides.\n\nhttps://events01.synchro tron.org.au/event/51/contributions/1128/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1128/ END:VEVENT BEGIN:VEVENT SUMMARY:Microparticle Production as Reference Materials for Particle Analy sis Methods in Safeguards DTSTART;VALUE=DATE-TIME:20171030T231500Z DTEND;VALUE=DATE-TIME:20171030T233000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1127@events01.synchrotron.org.au DESCRIPTION:Speakers: Stefan Neumeier (Forschungszentrum Jülich GmbH)\nTh e application of safeguards measures by the International Atomic Energy Ag ency (IAEA) involves analytical measurements of samples taken during inspe ctions and requires the development and advancement of analytical techniqu es. For quality control purposes\, the IAEA has expressed the need to acqu ire reference materials for particle analysis methods applied in safeguard s.\n\nTo this purpose\, a particle production facility was implemented at Forschungszentrum Jülich\, which is capable of producing microparticles i ntended as source material for certified reference materials for particle analysis methods applied in safeguards. A monodisperse particle size distr ibution as well as the single phase triuranium octoxide structure was conf irmed using SEM and µ-XRD/XANES\, respectively. Analysis performed on sin gle uranium microparticles confirmed consistency of the uranium isotopic r atios in comparison to the initial precursor solutions. To improve the hom ogeneity and particle handling\, the particles are transferred into suspen sions\, for which the stability was investigated with respect to dissoluti on and isotopic exchange.\n\nhttps://events01.synchrotron.org.au/event/51/ contributions/1127/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1127/ END:VEVENT BEGIN:VEVENT SUMMARY:Comparison of calculated and measured radionuclide inventory of a Zircaloy-4 cladding tube plenum section DTSTART;VALUE=DATE-TIME:20171030T063000Z DTEND;VALUE=DATE-TIME:20171030T064500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1126@events01.synchrotron.org.au DESCRIPTION:Speakers: Michel Herm (Karlsruhe Institute of Technology)\nCla dding tubes of water-cooled nuclear reactors are usually made of Zircaloy and are an important retaining element for radionuclides present in the fu el. However\, cladding integrity is affected by various processes during r eactor operation and beyond\, e.g. oxidation\, hydrogen uptake\, PCI\, fis sion product precipitation\, alpha-decay\, and radiation damage. Using exp erimental and modelling methods\, the radionuclide inventory of an irradia ted Zircaloy-4 plenum section is analyzed.\nQuantities of U-235/238\, Np-2 37\, Pu-238/239/240/241/242\, Am-241/243\, Cm-243/244 besides C-14\, Fe-55 \, Sb-125\, Cs-134/137 were (radio-)chemically determined in digested Zirc aloy-4 subsamples. Measured inventories of activation products in the Zr-a lloy are in good agreement with calculated values. However\, amounts of ac tinides and fission products exceed the calculated inventory by factor ~50 (Pu isotopes) and ~120 (Cs-137). Excess Pu and part of excess Cs inventor y originate from fuel residues on the inner cladding surface\, whereas vas t amount of cesium is volatilized from subjacent fuel pellets and transpor ted to the plenum.\n\nhttps://events01.synchrotron.org.au/event/51/contrib utions/1126/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1126/ END:VEVENT BEGIN:VEVENT SUMMARY:Synthesis and characterisation of rare Ce3NbO7 compounds for use a s nuclear space batteries by neutron powder diffraction and X-ray absorpti on spectroscopy DTSTART;VALUE=DATE-TIME:20171031T223000Z DTEND;VALUE=DATE-TIME:20171031T224500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1125@events01.synchrotron.org.au DESCRIPTION:Speakers: Sean Barlow (University of Sheffield)\nCe3NbO7 weber ite-type materials\, an inactive analogue for Am3NbO7\, have potential use in americium radioisotope thermoelectric generators to be developed by th e European Space Agency for scientific missions beyond the orbit of Jupite r. Ceramics with greater than 97% purity were synthesised by thermal solid -state reaction and analytically characterised by X-ray diffraction\, neut ron diffraction\, helium pycnometry\, Raman spectroscopy and X-ray absorpt ion spectroscopy. The Magnetochemistry of the system was calculated with t he Weiss temperature and magnetic moment per unit volume derived\, in good agreement against the theoretical values. Reitveld refinement of neutron data was employed to identify the crystal structure of the novel cerium ni obate and determine the correct orthorhombic space grouping from either Cm cm (No.63) or Pnma (No.62) space groups. Ce3NbO7 refined well under both s ystems indicating possible pseudosymmetry. Cerium in the +III oxidation st ate was observed by X-ray absorption spectroscopy confirming the chemical speciation within the structure.\n\nhttps://events01.synchrotron.org.au/ev ent/51/contributions/1125/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1125/ END:VEVENT BEGIN:VEVENT SUMMARY:Digital autoradiography on C-14 labelled PMMA impregnated rock sam ples using the Beaver$^{TM}$ DTSTART;VALUE=DATE-TIME:20171102T004500Z DTEND;VALUE=DATE-TIME:20171102T010000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1123@events01.synchrotron.org.au DESCRIPTION:Speakers: Mikko Voutilainen (Department of Chemistry\, Univers ity of Helsinki\, Finland)\nIn Finland and Sweden KBS-3 concept has been c hosen for disposal of spent nuclear fuel in crystalline rock. Recent trans port experiments have shown that heterogeneity of rock may play a major ro le in transport of radionuclides. Autoradiographic methods has been proven to be able to assist the characterization of heterogeneous structures. In this study we tested a novel digital autoradiographic device called Beave r$^{TM}$ which applies a Micro Patterned Gaseous Detector in order to quan titatively map beta emissions by C-14 atoms. The studied samples were impr egnated with C-14 labelled MMA (Methyl MethAcrylate) and polymerized to PM MA using heat. The Beaver$^{TM}$ was then used to determine concentration of C-14 atoms which can then be converted to porosity based on the amount of C-14 intruded into the rock sample. The resulting images show a heterog eneous distribution of porosity which arises from the different porosities of minerals. The samples were chosen from three sites that has been used recently in *in situ* diffusion experiments: Olkiluoto (Finland)\, Äspö (Sweden) and Grimsel (Switzerland).\n\nhttps://events01.synchrotron.org.au /event/51/contributions/1123/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1123/ END:VEVENT BEGIN:VEVENT SUMMARY:Efficient remediation of radiodine with silver-functionalized sili ca aerogel DTSTART;VALUE=DATE-TIME:20171101T041500Z DTEND;VALUE=DATE-TIME:20171101T044500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1122@events01.synchrotron.org.au DESCRIPTION:Speakers: Josef Matyas (Pacific Northwest National Laboratory) \nVarious volatile radionuclides are being released into gas streams and a queous solutions during reprocessing of used nuclear fuel and vitrificatio n of radioactive waste. Radioactive iodine-129 is of a particular concern because of its long half-life of 15.7 million years and the potential for biological processes to concentrate iodine. A number of materials are be ing developed worldwide to capture and immobilize iodine in a waste form o f a high chemical durability\; however\, none of them can be used as both a sorbent and a viable waste form. They can either encapsulate iodine-loa ded sorbent or sequester iodine that was removed from it. In the U.S.\, t he current benchmark for radioiodine capture is reduced silver mordenite ( AgZ) and that for the waste form is AgZ immobilized in a low-temperature g lass composite material. However\, the primary alternative option is a si lver-functionalized silica aerogel (Ag-aerogel). Ag-aerogel exhibits high capture efficiency (~ 500 mg/g) and selectivity for iodine (DF> 10000)\, and good resistance against aging in nuclear fuel reprocessing off-gas str eams. Its sorption performance is retained in deionized water and in a di lute salt solution with neutral pH containing iodide or iodate. A key adv antage of an Ag-aerogel is that\, after loading with iodine\, it can be co nsolidated into a dense and high-iodine-loaded silica-based waste form by simultaneous application of the heat and pressure. Presentation will disc uss the sorption performance of Ag-aerogel in different environments and p rovide an overview on the development of waste form.\n\nhttps://events01.s ynchrotron.org.au/event/51/contributions/1122/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1122/ END:VEVENT BEGIN:VEVENT SUMMARY:Invited Lecture: Plutonium Waste Management in the UK DTSTART;VALUE=DATE-TIME:20171029T234500Z DTEND;VALUE=DATE-TIME:20171030T001500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1121@events01.synchrotron.org.au DESCRIPTION:Speakers: Michael Slater (Invited Lecturer)\nPlutonium has ari sen from large scale reprocessing over many decades. When the programmes e nds around 2020 there will be approx. 140te of separated plutonium in UK. Current policy is safe and secure long term storage in modern purpose buil t stores. This requires ongoing active management and institutional contro ls including significant security costs and is not a lifecycle solution. D isposition options are being considered in order to put the material “be yond reach”:\n• Reuse as LWR MOX\n• Reuse in Candu EC6 Reactor s (CANMOX)\n• Reuse in GEH Prism Fast Reactor\n• Immobilisation – Hot Isostatic Pressing (HIP) along with other technologies including l ow spec MOX and downblending.\nThe current status of these options will be outlined along with work planned over the next few years further develop them in support of future UK Government policy decisions.\n\nhttps://event s01.synchrotron.org.au/event/51/contributions/1121/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1121/ END:VEVENT BEGIN:VEVENT SUMMARY:The development of zirconolite glass-ceramics for the immobilisati on of Pu-residues in the UK. DTSTART;VALUE=DATE-TIME:20171101T030000Z DTEND;VALUE=DATE-TIME:20171101T031500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1120@events01.synchrotron.org.au DESCRIPTION:Speakers: Stephanie Thornber (University of Sheffield)\nThe UK has over 100 tonnes of separated PuO2 stored at the Sellafield site. The UK policy for managing this plutonium stockpile is to reuse this material as MOx fuel. However\, not all of the material is suitable for reuse and a proportion has been classified as higher activity waste. These plutonium wastes\, and any material which is not ultimately reused\, will require i mmobilization\, in a passively safe wasteform\, for long-term storage and eventual geological disposal. One proposed treatment plan is hot isostatic pressing of the plutonium waste / stockpile material\, with suitable prec ursors\, to form a glass-ceramic or full ceramic wasteform\, inside stainl ess steel canisters. Glass-ceramic materials are proposed for the low puri ty and highly variable wastes\, in which the glass phase provides wastefor m flexibility to accommodate impurities and variations in the waste feed c omposition. The plutonium partitions into the more durable ceramic phase\, zirconolite (CaZrTi2O7). Zirconolite has excellent wasteform properties i ncluding durability and radiation tolerance\, and readily accepts actinide s and rare earths into its crystal structure.\n\nIn this work\, the format ion of zirconolite is shown to depend sensitively on glass fraction and co mposition\, such that an Al rich glass promotes a higher yield of zirconol ite. The thermodynamic activity of Si in the system drives the crystalline phase assemblage\, by determining whether it is consumed in the amorphous glass phase or undesired accessory crystalline phases\, such as sphene (C aTiSiO5) and zircon (ZrSiO4). The design of an optimized glass-ceramic fo rmulation is demonstrated\, to maximize the yield of zirconolite and minim ise the yield of accessory phases. The partitioning of CeO2\, within the glass-ceramic wasteform\, as a PuO2 surrogate\, was studied using various charge compensation mechanisms\, under an imposed Fe/FeO and Ni/NiO buffer . Analysis by SEM/EDX\, XRD\, and Ce L3 edge XANES\, demonstrated reducti on of Ce(IV) to Ce(III) to favour incorporation of Ce within a perovskite accessory phase and the glass matrix. Ce partitioning in the zirconolite phase was maximized when retained as Ce(IV). These results demonstrate a feasible wasteform formulation for disposition of UK plutonium wastes and stockpile material.\n\nhttps://events01.synchrotron.org.au/event/51/contri butions/1120/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1120/ END:VEVENT BEGIN:VEVENT SUMMARY:Interaction of nuclear safeguards and safety requirements when pla nning for waste disposal DTSTART;VALUE=DATE-TIME:20171030T213000Z DTEND;VALUE=DATE-TIME:20171030T220000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1118@events01.synchrotron.org.au DESCRIPTION:Speakers: Rebecca Stohr (Australian Safeguards and Non-Prolife ration Office)\nWaste conditioning is an important step in minimising and controlling the migration of radionuclides from disposed wastes into the e nvironment. However\, when nuclear materials are present\, consideration o f nuclear safeguards is also needed. Safeguards is the set of tools and te chniques used to ensure nuclear materials are only used for peaceful purpo ses. As part of a safeguards system\, nuclear materials need to be availab le for verification or rendered inaccessible in accordance with Internatio nal Atomic Energy Agency requirements. Inaccessibility requirements are no t driven by environmental degradation factors\, but on preventing recovery by motivated state actors. This presentation looks at the overlap between safety and safeguards requirements in Australia as well as safeguards-spe cific requirements when conditioning or disposing of nuclear materials.\n\ nhttps://events01.synchrotron.org.au/event/51/contributions/1118/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1118/ END:VEVENT BEGIN:VEVENT SUMMARY:Nuclear Waste Management update in Australia DTSTART;VALUE=DATE-TIME:20171029T231500Z DTEND;VALUE=DATE-TIME:20171029T234500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1117@events01.synchrotron.org.au DESCRIPTION:Speakers: Hefin Griffiths (ANSTO)\nAustralia is currently in t he process of establishing a National Radioactive Waste Management Facilit y and seeking to identify a site to host the facility. \nThe lecture will focus on the history of waste production in Australia\, the current manage ment of the diverse waste arisings\, particularly focussed on operational and legacy wastes held at the Australian Nuclear Science and Technology Or ganisation and the strategy applied to the management of those wastes.\nTh e process adopted to establish the facility will be discussed as well as p otential future options for the disposal of Intermediate Level Wastes. Aus tralia’s focus on investing in optimum wasteforms\, such as the vitrifie d residues from reprocessing spent fuel elements from current and previous research reactors and the synroc waste form for treating Intermediate Lev el Liquid Wastes\, will be discussed as case studies.\n\nhttps://events01. synchrotron.org.au/event/51/contributions/1117/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1117/ END:VEVENT BEGIN:VEVENT SUMMARY:Radiation stability study of melt processed and hot isostatically pressed multi-phase ceramic waste forms DTSTART;VALUE=DATE-TIME:20171031T050000Z DTEND;VALUE=DATE-TIME:20171031T051500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1116@events01.synchrotron.org.au DESCRIPTION:Speakers: Ming Tang (Los Alamos National Laboratory)\nMulti-ph ase ceramic waste forms were fabricated by melt-processing and hot isostat ic pressing (HIP) to immobilize alkaline/alkaline earth (Cs/Sr-CS) + lanth anide (LN) + transition metal (TM) fission product waste streams from nucl ear fuel reprocessing. Al2O3 and TiO2 were combined with these waste comp onents to produce multi-phase crystalline ceramics containing hollandite-t ype phases\, perovskites\, zirconolite/pyrochlores and other minor phases. In this study\, ion irradiations are performed to test and compare radiat ion tolerance of multi-phase ceramics produced via melting processing and HIP techniques. \nFor the radiation stability test\, selected crystalline ceramic samples are exposed to charge particles generated by an ion accel erator\, which is used to simulate self-radiation in a waste form. Ion ir radiation-induced microstructural modifications\, volume swelling and micr ocracking are examined using X-ray diffraction\, transmission electron mic roscopy\, scanning electron microscopy and other characterization methods. Our preliminary results reveal similar radiation tolerance in these mult i-phase ceramics with different fabrication techniques.\n\nhttps://events0 1.synchrotron.org.au/event/51/contributions/1116/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1116/ END:VEVENT BEGIN:VEVENT SUMMARY:The Corrosion of Copper Nuclear Waste Containers under Deep Geolog ic Disposal ConditionsF DTSTART;VALUE=DATE-TIME:20171030T060000Z DTEND;VALUE=DATE-TIME:20171030T061500Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1113@events01.synchrotron.org.au DESCRIPTION:Speakers: David Shoesmith (Western University)\nThe corrosion of high level copper nuclear waste containers under permanent disposal con ditions can occur via a number of processes which change in importance as the environment within a deep geologic repository evolves from warm and ox ic to cool and anoxic. Under warm and oxic conditions the container could be exposed to gamma irradiated conditions which evolve from aerated vapour to fully saturated aqueous conditions. During this period the possibility of localized corrosion (e.g.\, pitting) must be considered. Over extended exposure periods when anoxic conditions prevail corrosion will be sustain ed by reaction with sulphide produced either by remote microbial activity or the dissolution of sulphides present in the clays compacted around the container. Studies to understand and quantify both these corrosion process es are underway. In this presentation these studies will be discussed and their use in the development of corrosion models described.\n\nhttps://eve nts01.synchrotron.org.au/event/51/contributions/1113/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1113/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards understanding the dissolution of vitrified nuclear waste i n a cementitious geological disposal facility DTSTART;VALUE=DATE-TIME:20171031T000000Z DTEND;VALUE=DATE-TIME:20171031T003000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1112@events01.synchrotron.org.au DESCRIPTION:Speakers: Claire Corkhill (NucleUS Immobilisation Science Labo ratory\, University of Sheffield\,)\nUnder the generic scenario envisaged for the geological disposal of vitrified UK high- and intermediate-level w aste glass (HLW and ILW\, respectively)\, high pH environments\, formed th rough degradation of the cementitious engineered barrier\, are expected to dominate the ground water chemistry thousands of years into the future. W e highlight the main findings of a number of recent and ongoing studies th at aim to evaluate and understand how cementitious groundwater composition s influence the dissolution rate of vitrified wasteforms\, including: simu lant UK HLW\; the International Simple Glass\; natural basaltic glass and glasses designed for ILW. Briefly\, we discuss results detailing the mecha nisms of alteration layer formation in Ca-rich systems\; we describe the i nfluence of idealised cement leachate solutions on ion-exchange processes during the initial stages of dissolution\; and we review the application o f single-pass flow-through methods to derive the fundamental parameters ne cessary to model the dissolution kinetics of vitrified waste.\n\nhttps://e vents01.synchrotron.org.au/event/51/contributions/1112/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1112/ END:VEVENT BEGIN:VEVENT SUMMARY:Hot isostatic pressing of ion exchange materials\, from the Fukush ima and Sellafield sites\, to produce ceramic wasteforms. DTSTART;VALUE=DATE-TIME:20171031T213000Z DTEND;VALUE=DATE-TIME:20171031T220000Z DTSTAMP;VALUE=DATE-TIME:20260519T101604Z UID:indico-contribution-51-1111@events01.synchrotron.org.au DESCRIPTION:Speakers: Neil Hyatt (University of Sheffield)\nDecommissionin g and clean up of nuclear facilities requires the development of new techn ologies to condition radioactive wastes\, producing passively safe waste p ackages of minimal volume\, to reduce storage and disposal costs. We have applied hot isostatic pressing to demonstrate conceptual wasteforms for i on exchange materials and sludges present on the Sellafield site\, UK\, an d Fukushima site\, Japan. These radioactive wastes pose several challenge s which demand early conditioning to produce a passively safe wasteform\, including: i) the materials are of a wet and granular nature\, and hence d ispersible as a result of loss of containment\; ii) the materials are char acterised by very high dose rates as a result of their selectivity for sho rt lived radionuclides (e.g. Sr-90\, Cs-137\, Co-60)\; iii) the materials exhibit radiogenic self heating\, as a result of the concentration of such lived radio nuclides\; iv) the materials exhibit hydrogen production as a result of radiolysis of entrained water.\nIn this presentation we demonst rate the conversion of several commercial and natural inorganic ion exchan ge materials into multiphase ceramic wasteforms\, achieving a waste loadin g of 100 wt% and density in excess of 97% theoretical. High resolution th ermogravimetric analysis coupled with mass spectroscopy was utilised to ch aracterise the evolution of water and volatiles during the in-can bake out step\, prior to the HIP cycle. This allowed optimisation of the bake out parameters (temperature\, time and vacuum) to enable complete removal of water and volatiles\, affording ceramic bodies with minimal residual poros ity by hot isostatic pressing at 1250oC for 4h in stainless steel cans. Ch aracterisation of the ceramic wasteforms by SEM /EDX and X-ray diffraction revealed the nuclides of concern to be incorporated within well known nat ural mineral and synthetic phases\, with Sr partitioning into the SrTiO3 p ervoskite phase and Co\, Fe\, Mn and Cr partitioning into a spinel phase. Dynamic alteration experiments revealed matrix dissolution rates of less than 10-4 g m-2 d-1 under forward rate conditions at 90 oC.\nOverall\, hot isostatic pressing of inorganic ion exchange materials yields durable gla ss\, glass-ceramic\, and ceramic wasteforms\, with minimal voidage and por osity\, in which the radionuclide partitioning between glass and ceramic p hases can be controlled by wasteform composition and processing parameters . The resulting ceramic wasteforms are considered to meet the disposabili ty requirements of a UK Geological Disposal Facility for radioactive waste s.\n\nhttps://events01.synchrotron.org.au/event/51/contributions/1111/ LOCATION: URL:https://events01.synchrotron.org.au/event/51/contributions/1111/ END:VEVENT END:VCALENDAR