.. .. Dans-le-matériau and . .. Dans-le-matériau, 143 Image 20 : Images MEB (gauche) et MET (droite) de l'oxyde d'uranium UO2+x et de l'oxyde mixte U0,5Ce0,5O2+x obtenus par réaction SCS de mélanges U/acide citrique et U-Ce/acide citrique à ?=1, Images MEB des poudres Gd/acide citrique à 550 °C à ?=0,75 et ?=1 et image MET de la poudre à ?=1, vol.11

/. De-la-pastille-u-ce and . .. Ac, 1.2. Synthèse sur plaque chauffante Les synthèses effectuées en plaque chauffante ont été effectuées sous air ambiant dans un bécher. Le mélange est chauffé à 115 °C pour permettre la déshydratation et la formation du gel. Par la suite, pp.10-13

, Pour la glycine, le coefficient stoechiométrique est donc de 15/9 (pour une richesse de 1), l'étude paramétrique s'intéresse donc à faire varier la richesse du mélange de 0,3 à 2,2. -Pour l'acide citrique, le coefficient stoechiométrique est donc de, vol.15

, étudierons pas de richesse sur-stoechiométrique pour éviter des résidus de carbone trop important. L'étude paramétrique s'intéresse donc à faire varier la richesse du mélange de 0,3 à 1. -Pour l'urée, le coefficient stoechiométrique est donc de 15/6 (pour une richesse de 1)

, Dans certains cas (acide citrique, urée), la poudre obtenue a été traitée à 550 °C pour éliminer les résidus organiques. Le tableau ci-dessous liste les masses de combustible utilisé et de poudre récupérée après traitement thermique ainsi que la température d'ignition observée

. De-maille, A. L. Décrite-par, and . Bail, est appliquée à l'aide du programme Fullprof 5 . Les variables affinées sont les variables de « position des raies » et de « profil des raies ». Il n'existe pas de contrainte sur les intensités qui sont calculées par itérations successives. Le fond continu est séparé de la diffraction de Bragg et est pointé

, L'affinement des paramètres de profil est réalisé suivant l'ordre indiqué ci-dessous

W. and T. Non, dépendant de ??dans la fonction de Caglioti qui détermine la largeur à mi-hauteur (H) de chaque pic par l'équation suivante

, Shape1, facteur de mélange de la fonction

V. and T. Dépendant-de-??dans-la-fonction-de-caglioti,

, La qualité d'un affinement de profil type « Le Bail » est définie à l'aide de plusieurs facteurs de confiance

, Les pastilles ont été préparées par pressage uni axial d'une masse approximative de 350 mg de poudre, broyée manuellement et sans autre composé ajouté (liant ou autre), à une pression de 2 atm pour un diamètre de matrice de 8,10 mm. La densification des pastilles a été étudiée sur un dilatomètre modèle Setaram Setsys Evolution sous argon hydrogéné

, Les pastilles avant et après frittage ont été mesurées géométriquement et les densités ont été calculées puis comparées à la densité théorique de l'UO2 (10,97 g/cm 3 ). L'effet du traitement thermique sur la densification des pastilles a été étudié en dilatomètre. Les mesures ont été effectuées sur un appareil modèle Setsys Setaram Evolution, sous un flux d'argon hydrogéné (Ar/5%H2), sur des pastilles crues tenues entre deux plaquettes en alumine pour éviter le contact entre l'échantillon, la nacelle, 1200.

, Annexe 6

, Dans le but d'étudier les réactions entre le nitrate et la glycine avant l'ignition du gel

E. Lafontaine and M. Comet, Les nanothermites -préparation, propriétés, applications, et perspectives, pp.102-105, 2016.

, ASTRID, un démonstrateur technologique pour la quatrième génération de réacteurs nucléaires 3. French National Plan for the management of Radioactive Materials and Waste, 2016.

H. Goldschmidt and C. Vautin, Aluminum as a heating and reducing agent, J. Soc. Chem. Ind, vol.19, p.543, 1898.

H. Goldschmidt, Zentralbehörden und Beamtentum im Kurfürstentum Mainz vom 16.-18. Jh. Iron Age, vol.82, p.232, 1908.

A. G. Merzhanov, I. P. Borovinskaya, V. M. Shkiro, and U. S. , Inventors certificate N°255221, 0225.

A. G. Merzhanov, Self-developing high-temperature synthesis of refractory compounds, Vestn. Akad. Nauk SSSR N, vol.10, pp.76-84, 1976.

A. G. Merzhanov, SHS-process: combustion theory and practice, Arch. Combust, vol.191, pp.23-48, 1981.

. Dr, R. G. Blair, and R. B. , Prof. Kaner, Chemfiles, vol.5

A. Varma, A. S. Mukasyan, A. S. Rogachev, and K. V. Manukyan, Solution Combustion Synthesis of Nanoscale Materials, Chem. Rev, vol.116, pp.14493-14586, 2016.

S. T. Aruna and K. S. Rajam, Mixture of fuels approach for the solution combustion synthesis of Al2O3-ZrO2 nanocomposite, Materials Research Bulletin, vol.39, issue.2, pp.157-167, 2004.

W. Wen and J. M. Wu, Nanomaterials via solution combustion synthesis a step nearer to controllability, vol.4, pp.58090-58100, 2014.

K. C. Patil, S. T. Aruna, and T. Mimani, Combustion synthesis an update. Current Opinion in Solid State & Materials Science, vol.6, pp.507-512, 2002.

K. C. Patil, M. S. Hegde, T. Rattan, and S. T. Aruna, Chemistry of Combustion Synthesis, Properties and Applications Nanocrystalline Oxide Materials, 2008.

C. C. Hwang, J. S. Tsai, and T. H. Huang, Combustion synthesis of Ni-Zn ferrite by using glycine and metal nitrates-investigations of precursor homogeneity, product. Materials Chemistry and Physics, vol.93, pp.330-336, 2005.

A. Cross, S. Roslyakov, K. V. Manukyan, S. Rouvimov, A. S. Rogachev et al.,

A. S. Wolff and . Mukasyan, In Situ Preparation of Highly Stable Ni-Based Supported Catalysts by Solution Combustion Synthesis, Journal of Physical Chemistry C, vol.118, issue.45, pp.26191-26198, 2014.

G. Peter-soldani, Approche structurale et phénoménologique de la conversion directe ou modifiée de nitrates d'actinide(s) en oxyde, 2013.

A. Varma and A. S. Mukasyan, Combustion synthesis of advanced materials: Fundamentals and applications, Korean Journal of Chemical Engineering, vol.21, issue.2, pp.527-536, 2004.

C. C. Hwang, T. H. Huang, J. S. Tsai, C. S. Lin, and C. H. Peng, Combustion synthesis of nanocrystalline ceria (CeO2) powders by a dry route, Materials Science and Engineering B-Solid State Materials for Advanced Technology, vol.132, issue.3, pp.229-238, 2006.

K. H. Wu, C. H. Yu, Y. C. Chang, and D. N. Horng, Effect of pH on the formation and combustion process of sol-gel auto-combustion derived NiZn ferrite/SiO2 composites, Journal of Solid State Chemistry, vol.177, pp.4119-4125, 2004.

J. Toniolo, A. S. Takimi, M. J. Andrade, R. Bonadiman, and C. P. Bergmann, Synthesis by the solution combustion process and magnetic properties of iron oxide (Fe3O4 and ?-Fe2O3) particles, Journal of Materials Science, vol.42, issue.13, pp.4785-4791, 2007.

A. Ashok, A. Kumar, R. R. Bhosale, M. A. Saleh, U. K. Ghosh et al., Cobalt oxide nanopowder synthesis using cellulose assisted combustion technique, Ceramics International, vol.42, issue.11, pp.12771-12777, 2016.

K. V. Manukyan, A. Cross, S. Roslyakov, S. Rouvimov, A. S. Rogachev et al., Solution Combustion Synthesis of Nano-Crystalline Metallic Materials: Mechanistic Studies, Journal of Physical Chemistry C, vol.117, issue.46, pp.24417-24427, 2013.

C. C. Hwang and T. Y. Wu, Synthesis and characterization of nanocrystalline ZnO powders by a novel combustion synthesis method. Materials Science and Engineering B-Solid State Materials for Advanced Technology, vol.111, pp.197-206, 2004.

J. Chandradass, M. H. Kim, and D. S. Bae, Influence of citric acid to aluminium nitrate molar ratio on the combustion synthesis of alumina-zirconia nanopowders, Journal of Alloys and Compounds, vol.470, issue.1-2, pp.9-12, 2009.

Y. W. Jiang, S. G. Yang, Z. H. Hua, J. F. Gong, and X. N. Zhao, Sol-gel auto-combustion synthesis of totally immiscible NiAg alloy, Materials Research Bulletin, vol.46, issue.12, pp.2531-2536, 2011.

A. S. Mukasyan, P. Epstein, and P. Dinka, Solution combustion synthesis of nanomaterials. Proceedings of the Combustion Institute, vol.31, pp.1789-1795, 2007.

F. Deganello, G. Marci, and G. Deganello, Citrate-nitrate auto-combustion synthesis of perovskite-type nanopowders: A systematic approach, Journal of the European Ceramic Society, vol.29, issue.3, pp.439-450, 2009.

R. S. Guo, Q. T. Wei, H. L. Li, and F. H. Wang, Synthesis and properties of La0.7Sr0.3MnO3 cathode by gel combustion, Materials Letters, vol.60, issue.2, pp.261-265, 2006.

S. H. Vajargah, H. R. Hosseini, and Z. A. Nemati, Synthesis of nanocrystalline yttrium iron garnets by sol-gel combustion process: The influence of pH of precursor solution. Materials Science and Engineering B-Solid State Materials for Advanced Technology, vol.129, pp.211-215, 2006.

C. C. Hwang, T. Y. Wu, J. Wan, and J. S. Tsai, Development of a novel combustion synthesis method for synthesizing of ceramic oxide powders. Materials Science and Engineering B-Solid State Materials for Advanced Technology, vol.111, pp.49-56, 2004.

J. H. Bai, F. T. Meng, C. C. Wei, Y. X. Zhao, H. H. Tan et al., Solution Combustion Synthesis and Characteristics of, Nanoscale MgO Powders. Ceramics -Silikáty, vol.55, issue.1, pp.20-25, 2011.

K. Deshpande and A. Mukasyan, Direct Synthesis of Iron Oxide Nanopowders by the Combustion Approach Reaction Mechanism and Properties, Chemistry of Materials, vol.16, issue.24, pp.4896-4904, 2004.

T. Striker and J. A. Ruud, Effect of Fuel Choice on the Aqueous Combustion Synthesis of Lanthanum Ferrite and Lanthanum Manganite, Journal of the American Ceramic Society, vol.93, issue.9, pp.2622-2629, 2010.

R. K. Lenka, T. Mahata, P. K. Sinha, and A. K. Tyagi, Combustion synthesis of gadolinia-doped ceria using glycine and urea fuels, Journal of Alloys and Compounds, vol.466, issue.1-2, pp.326-329, 2008.

A. Vita, C. Italiano, C. Fabiano, M. Lagana, and L. Pino, Influence of Ce-precursor and fuel on structure and catalytic activity of combustion synthesized NiCeO2 catalysts for biogas oxidative steam reforming, Materials Chemistry and Physics, vol.163, pp.337-347, 2015.

A. Mukasyan and P. Dinka, Novel Approaches to Solution-Combustion Synthesis of Nanomaterials, International Journal of Self-Propagating High-Temperature Synthesis, vol.16, pp.23-35, 2007.

R. D. Purohit, B. P. Sharma, K. T. Pillai, and A. K. Tyagi, Ultrafine ceria powders via glycinenitrate combustion, Materials Research Bulletin, vol.36, issue.15, pp.2711-2721, 2001.

K. S. Martirosyan, L. Wang, A. Vicent, and D. Luss, Synthesis and performance of bismuth trioxide nanoparticles for high energy gas generator use, Nanotechnology, issue.40, p.20, 2009.

T. V. Anuradha, S. Ranganathan, T. Mimani, K. C. Patil, C. Synthesis et al., Scripta Materialia, vol.44, issue.8-9, pp.2237-2241, 2001.

L. Yulin, Y. Jun, L. Xiaoci, H. Weiya, T. Yu et al., Combustion synthesis and stability of nanocrystalline La2O3 via ethanolamine-nitrate process, Journal of Rare Earths, vol.30, issue.1, pp.48-52, 2012.

P. K. Patro, A. R. Kulkarni, and C. S. Harendranath, Combustion synthesis of Sr0.5Ba0.5Nb2O6 and effect of fuel on its microstructure and dielectric properties, Materials Research Bulletin, vol.38, issue.2, pp.249-259, 2003.

E. Esmaeili, M. Salavati-niasari, F. Mohandes, F. Davar, and H. Seyghalkar, Modified singlephase hematite nanoparticles via a facile approach for large-scale synthesis, Chemical Engineering Journal, vol.170, issue.1, pp.278-285, 2011.

M. Valefi, C. Falamaki, T. Ebadzadeh, and M. S. Hashjin, New Insights of the Glycine-Nitrate Process For the Synthesis of Nano-Crystalline 8YSZ, Journal of the American Ceramic Society, vol.90, issue.7, pp.2008-2014, 2007.

N. Srinatha, V. D. Kumar, N. K. , and B. Angadi, The effect of fuel and fuel-oxidizer combinations on ZnO nanoparticles synthesized by solution combustion technique, Advanced Powder Technology, vol.26, issue.5, pp.1355-1363, 2015.

R. Ianos, I. Lazau, C. Pacurariu, and P. Barvinschi, Fuel mixture approach for solution combustion synthesis of Ca3Al2O6 powders. Cement and Concrete Research, vol.39, pp.566-572, 2009.

K. Tahmasebi and M. H. Paydar, The effect of starch addition on solution combustion synthesis of Al2O3-ZrO2 nanocomposite powder using urea as fuel, Materials Chemistry and Physics, vol.109, issue.1, pp.156-163, 2008.

J. Schafer, W. Sigmund, S. Roy, and A. Aldinger, Low temperature synthesis of ultrafine Pb(Zr, Ti)O3 powder by sol-gel combustion, J. Mater. Res, vol.12, pp.2518-2521, 1997.

R. D. Purohit, S. Saha, and A. K. Tyagi, Nanocrystalline thoria powders via glycine-nitrate combustion, Journal of Nuclear Materials, vol.288, issue.1, pp.7-10, 2001.

G. Barenblatt, V. Librovich, and G. Makhviladze, The Mathematical Theory of Combustion and Explosions, Consultants Bureau, 0331.

A. Shiryaev and J. Eng, Phys. Thermophys, vol.65, pp.957-962, 1993.

A. S. Mukasyan and P. Dinka, Novel Approaches to Solution-Combustion Synthesis of Nanomaterials, International Journal of Self-Propagating High-Temperature Synthesis, vol.16, pp.23-35, 2007.

A. Kumar, E. E. Wolf, and A. S. Mukasyan, Solution combustion synthesis of metal nanopowders: Nickel-Reaction pathways, AlChe Journal, vol.57, issue.8, pp.2207-2214, 2011.

A. Kumar, E. E. Wolf, and A. S. Mukasyan, Solution combustion synthesis of metal nanopowders: Copper and copper/nickel alloys, AlChe Journal, vol.57, issue.12, pp.3473-3479, 2011.

P. Erri, J. Nader, and A. Varma, Controlling Combustion Wave Propagation for Transition Metal Alloy Cermet Foam Synthesis, Advanced Materials, vol.20, issue.7, p.1243, 2008.

A. S. Mukasyan, C. Costello, K. P. Sherlock, D. Lafarga, and A. Varma, Perovskite membranes by aqueous combustion synthesis and properties. Separation and Purification Technology, vol.25, pp.117-126, 2001.

S. R. Nair, R. D. Purohit, A. K. Tyagi, P. K. Sinha, and B. P. Sharma, Role of glycine-to-nitrate ratio in influencing the powder characteristics of La(Ca)CrO3, Materials Research Bulletin, vol.43, issue.6, pp.1573-1582, 2008.

L. Garcia, F. , A. Peigney, and C. Laurent, Tetragonal-(Zr,Co)O2 solid solution Combustion synthesis, thermal stability in air and reduction in H2, H2-CH4 and H2-C2H4 atmospheres, Materials Research Bulletin, vol.43, pp.3088-3099, 2008.

S. T. Mukherjee, V. Bedekar, A. Patra, P. U. Sastry, and A. K. Tyagi, Study of agglomeration behavior of combustion-synthesized nano-crystalline ceria using new fuels, Journal of Alloys and Compounds, vol.466, issue.1-2, pp.493-497, 2008.

J. Yang, X. Li, J. Zhoua, Y. Tanga, Y. Zhanga et al., Factors controlling pure-phase magnetic BiFeO3 powders synthesized by solution combustion synthesis, Journal of Alloys and Compounds, vol.509, pp.9271-9277, 2011.

C. H. Jung, S. Jalota, and S. B. Bhaduri, Quantitative effects of fuel on the synthesis of Ni NiO particles using a microwave-induced solution combustion synthesis in air atmosphere, Materials Letters, vol.59, pp.2426-2432, 2005.

Q. G. Wang, R. R. Peng, C. R. Xia, W. Zhu, and H. T. Wang, Characteristics of YSZ synthesized with a glycine-nitrate process, Ceramics International, vol.34, issue.7, pp.1773-1778, 2008.

B. Murugan, A. V. Ramaswamy, D. Srinivas, C. S. Gopinath, and V. Ramaswamy, Effect of fuel and its concentration on the nature of Mn in MnCeO2 solid solutions prepared by solution combustion synthesis, Acta Materialia, vol.56, issue.7, pp.1461-1472, 2008.

C. Peng and Z. Zhang, Nitrate-citrate combustion synthesis of Ce1?xGdxO2x2 powder and its characterization, Ceramics International, vol.33, issue.6, pp.1133-1136, 2007.

K. Ananthasivan, S. Anthonysamy, C. Sudha, A. L. Terrance, and P. R. Rao, Thoria doped with cations of group VB-synthesis and sintering, Journal of Nuclear Materials, vol.300, issue.2-3, pp.217-229, 2002.

A. S. Rogachev and A. S. Mukasyan, Combustion of Heterogeneous Nanostructural Systems (Review). Combustion Explosion and Shock Waves, vol.46, pp.243-266, 2010.

A. Kumar, A. S. Mukasyan, and E. E. Wolff, Combustion synthesis of Ni, Fe and Cu multicomponent catalysts for hydrogen production from ethanol reforming, Applied Catalysis A: General, vol.401, pp.20-28, 2011.

S. Banerjee, A. Kumar, and P. S. Devi, Preparation of nanoparticles of oxides by the citratenitrate process, Journal of Thermal Analysis and Calorimetry, vol.104, issue.3, pp.859-867, 2011.

R. Venkata-krishnan, R. Manikandan, H. Jena, and K. Nagarajan, Heat capacity of La6UO12, Sm6UO12 and Eu6UO12 by DSC, Thermochimica Acta, vol.472, issue.1-2, pp.95-98, 2008.

R. Venkata-krishnan, G. Panneerselvam, P. Manikandan, M. P. Antony, and K. Nagarajan, Heat Capacity and Thermal Expansion of Uranium-Gadolinium Mixed Oxides, Journal of Nuclear and Radiochemical Sciences, vol.10, pp.19-26, 2009.

R. Venkata-krishnan, V. K. Mittal, R. Babu, A. Senapati, S. Bera et al., Heat capacity measurements and XPS studies on uranium-lanthanum mixed oxides, Journal of Alloys and Compounds, vol.509, issue.7, pp.3229-3237, 2011.

R. Venkata-krishnan, G. Jogeswararao, G. Panneerselvam, M. P. Antony, and K. Ananthasivan, Solid solubility and thermal expansion studies of uraniumeeuropium mixed oxides, Journal of Nuclear Materials, vol.465, pp.719-723, 2015.

R. Venkata-krishnan and K. Nagarajan, Heat capacity measurements on uranium-cerium mixed oxides by differential scanning calorimetry, Thermochimica Acta, vol.440, issue.2, pp.141-145, 2006.

H. Jena, R. Asuvathraman, and K. V. Kutty, Combustion synthesis and thermal expansion measurements of the rare earth-uranium ternary oxides RE6UO12, Journal of Nuclear Materials, vol.280, issue.3, pp.312-317, 2000.

S. K. Gupta, N. Pathak, and R. M. Kadam, Probing local coordination and oxidation state of uranium in ThO2 U nanostructured, Journal of Molecular Structure, vol.1102, pp.81-85, 2015.

R. Vauchy, R. C. Belin, A. Robisson, F. Lebreton, L. Aufore et al., Actinide Oxidation State and OM Ratio in Hypostoichiometric Uranium?Plutonium?Americium U0.750Pu0.246Am0.004O2?x Mixed Oxides, vol.55, pp.2123-2132, 2016.
URL : https://hal.archives-ouvertes.fr/cea-02528980

V. D. Zhuravlev, V. G. Bamburov, L. V. Ermakova, and N. I. Lobachevskaya, Synthesis of Functional Materials in Combustion Reactions, Physics of Atomic Nuclei, vol.78, issue.12, pp.1389-1405, 2015.

S. Kumar, D. , K. Ananthasivan, R. Venkata-krishnan, S. Amirthapandian et al., Bulk synthesis of nanocrystalline urania powders by citrate gel-combustion method, Journal of Nuclear Materials, vol.468, pp.178-193, 2016.

S. Anthonysamy, K. Ananthasivan, V. Chandramouli, I. Kaliappan, and P. R. Rao, Combustion synthesis of urania±thoria solid solutions, Journal of Nuclear Materials, vol.278, issue.2-3, pp.346-357, 2000.

D. Maji, K. Ananthasivan, R. Venkata-krishnan, S. Balakrishnan, S. Amirthapandian et al., Nanocrystalline (U0.5Ce0.5)O2±x solid solutions through citrate gelcombustion, Journal of Nuclear Materials, vol.502, pp.370-379, 2018.

V. Chandramouli, S. Anthonysamy, P. R. Rao, R. Divakar, and D. Sundararaman, Microwave synthesis of solid solutions of urania thoria a comparative study, Journal of Nuclear Materials, vol.254, issue.1, pp.55-64, 1998.

S. Anthonysamy, K. Joseph, T. Gnanasekaran, and P. R. Rao, Studies on the kinetics of oxidation of urania-thoria solid solutions in air, Journal of Nuclear Materials, vol.280, issue.1, pp.25-32, 2000.

R. Venkata-krishnan, R. Babu, G. Panneerselvam, B. M. Singh, A. Senapati et al., Solubility studies and thermophysical properties of uraniumneodymium mixed oxides system, Ceramics International, vol.40, issue.3, pp.4395-4405, 2014.

R. Venkata-krishnan, G. Panneerselvam, M. P. Antony, and K. Nagarajan, Solubility studies and thermal expansion coefficient of uranium-lanthanum mixed oxide system, Journal of Nuclear Materials, vol.403, pp.25-31, 2010.

A. Jain, K. Ananthasivan, S. Anthonysamy, and P. R. Rao, synthesis and sintering of (U0.72Ce0.28)O2 solid solution, Journal of Nuclear Materials, vol.345, issue.2-3, pp.245-253, 2005.

A. Sonzogni, Synthèses d'oxydes d'uranium par combustion thermique (stage), 2015.

K. B. Hussein, Study of Temperature Effect on Reaction Product of Some Lanthanide Metal Ions With Urea, Wasiit Journall for Sciience & Medicine, vol.3, issue.2, pp.29-36, 2010.

H. G. Brittain, Z. Konteatis, S. Chemistry, S. Lanthanide-complexes--ill, . Studies et al., , vol.43, pp.1719-1723, 1980.

J. J. Kingsley and K. C. Patil, A NOVEL COMBUSTION PROCESS FOR THE SYNTHESIS OF FINE PARTICLE ALPHA-ALUMINA AND RELATED OXIDE MATERIALS, Materials Letters, issue.6, pp.427-432, 1988.

L. A. Chick, L. R. Pederson, G. D. Maupin, J. L. Bates, L. E. Thomas et al., Glycinenitrate combustion synthesis of oxide ceramic powders, MATERIALS LETTERS, issue.10, 1990.

K. Deshpande, A. Mukasyan, and A. Varma, Direct synthesis of iron oxide nanopowders by the combustion approach: Reaction mechanism and properties, Chemistry of Materials, vol.16, issue.24, pp.4896-4904, 2004.

J. C. Toniolo, M. D. Lima, A. S. Takimi, and C. P. Bergmann, Synthesis of alumina powders by the glycine-nitrate combustion process, Materials Research Bulletin, vol.40, pp.561-571, 2005.

R. Ianos, I. Lazau, C. Pacurariu, and P. Barvinschi, Fuel mixture approach for solution combustion synthesis of Ca3Al2O6 powders. Cement and Concrete Research, vol.39, pp.566-572, 2009.

K. A. Singh, L. C. Pathak, and S. K. Roy, Effect of citric acid on the synthesis of nano-crystalline yttria stabilized zirconia powders by nitrate-citrate process, Ceramics International, vol.33, pp.1463-1468, 2007.

L. Lépine, R. Gilbert, and G. Bélanger, Ultraviolet Spectrophotometrlc Determination of Gadolinium in Concentrated Solutions of Nitrate Salts, Anal. Chem, vol.58, pp.1152-1156, 1986.

P. P. Lima, R. A. Ferreira, R. O. Freire, F. A. Paz, L. Fu et al., Spectroscopic Study of a UV-Photostable Organic-Inorganic Hybrids Incorporating an Eu3+ b-Diketonate Complex, ChemPhysChem, vol.7, pp.735-746, 2006.

K. Kumar, J. Gunasekaran, S. , S. Loganathan, G. Anand et al., The molecular structure, geometry, stability, thermal and fundamental modes of vibration of glycine dimer by DFT methods, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, vol.115, pp.730-737, 2013.

Q. G. Wang, R. R. Peng, C. R. Xia, W. Zhu, and H. T. Wang, Characteristics of YSZ synthesized with a glycine-nitrate process, Ceramics International, vol.34, issue.7, pp.1773-1778, 2008.

X. Liu, Y. Guo, Y. Wang, J. Ren, Y. Wang et al., Direct synthesis of mesoporous Fe3O4 through citric acid-assisted solid thermal decomposition, J Mater Sci, vol.45, pp.906-910, 2010.

M. J. Locke and M. R. , Effect of Solvation on the Acid/Base Properties of Glycine, J. Am. Chem. Soc, vol.105, pp.4226-4232, 1983.

M. Huang, S. Lu, and C. Zhoua, Thermal decomposition kinetics of glycine in nitrogen atmosphere, Thermochimica Acta, vol.552, pp.60-64, 2013.

M. Valefi, C. Falamaki, T. Ebadzadeh, and M. S. Hashjin, New insights of the glycine-nitrate process for the synthesis of nano-crystalline 8YSZ, Journal of the American Ceramic Society, vol.90, issue.7, pp.2008-2014, 2007.

A. Ohyoshi, K. Ueno, . Studies, . Actinide, and . Vi, PHOTOCHEMICAL REDUCTION OF URANYL ION IN CITRIC ACID SOLUTION J. Inorganic Nuclear Chemistry, vol.36, pp.379-384, 1974.

R. O. Fuentes and R. T. Baker, Synthesis of Nanocrystalline CeO2-ZrO2 Solid Solutions by a Citrate Complexation Route: A Thermochemical and Structural Study, Journal of Physical Chemistry C, vol.113, issue.3, pp.914-924, 2009.

S. A. Seyyed-ebrahimi and S. M. Masoudpanah, Effects of pH and citric acid content on the structure and magnetic properties of MnZn ferrite nanoparticles synthesized by a sol-gel autocombustion method, Journal of Magnetism and Magnetic Materials, vol.357, pp.77-81, 2014.

J. J. Katz and G. T. Seaborg, The Chemistry of the Actinide and Transactinide Elements, pp.1-6, 2006.

B. Belbeoch and J. C. Boivineau, Changements de structure de l'oxyde U4O9

. Minéral and . Cristallogr, , pp.558-563, 1967.

I. Sheft, S. Fried, and N. Davidson, Preparation of Uranium Trioxide, Journal of the American Chemical Society, vol.72, pp.2172-2173, 1950.

V. J. Wheeler, R. M. Dell, and E. Wait, Uranium trioxide and the UO3 hydrates, J. Inorganic Nuclear Chemistry, vol.26, pp.1829-1845, 1964.

R. D. Kozlova, V. A. Matyukha, and N. V. Dedov, Mechanism and kinetics of thermal decomposition of uranyl nitrate hexahydrate under the nonisothermal conditions. Radiochemistry, vol.49, pp.130-134, 2007.

S. Aronson, R. B. Roof, and J. Belle, Kinetic study of the oxidation of uranium dioxide, The Journal of Chemical Physics, vol.27, issue.1, pp.137-144, 1957.

R. J. Mc-eachern and P. Taylor, A review of the oxidation of uranium dioxide at temperatures below 400°C, Journal of Nuclear Materials, vol.254, pp.87-121, 1998.

S. Kumar, D. , K. Ananthasivan, R. Venkata-krishnan, D. Maji et al., A novel gel combustion procedure for the preparation of foam and porous pellets of UO2, Journal of Nuclear Materials, vol.483, pp.199-204, 2017.

B. V. Ayodele, M. A. Hossain, S. L. Chong, J. C. Soh, S. Abdullah et al., Non-isothermal kinetics and mechanistic study of thermal decomposition of light rare earth metal nitrate hydrates using thermogravimetric analysis, J Therm Anal Calorim, vol.125, pp.423-435, 2016.

P. P. Melnikov, V. A. Nascimento, and L. Z. Zanoni-consolo, Computerized Modeling of Intermediate Compounds Formed During Thermal Decomposition of Gadolinium Nitrate Hydrate, Russian Journal of Physical Chemistry A, vol.86, issue.11, pp.1659-1663, 2012.

M. M. Barbooti and D. A. Al-sammerrai, Thermal Decomposition of Citric Acid, Thermochimica Acta, vol.98, pp.119-126, 1986.

O. Boudouard, B. Belbeoch, E. Laredo, and P. Perio, Sur la decomposition de loxyde de carbone en presence des oxydesmetalliques, Journal of Nuclear Materials, vol.13, pp.100-106, 1964.

J. Nigon, L. Bastard, and G. , Fabrication des combustibles au plutonium pour les RNR. Techniques de l'Ingénieur, pp.3632-3633, 2003.

, Une monographie de la Direction de l'Energie Nucléaire -Les combustibles nucléaires

C. Chambon, S. Vaudez, and J. Heintz, De-densification mechanisms of yttria-doped cerium oxide during sintering in a reducing atmosphere, J Am Ceram Soc, vol.101, pp.4956-4967, 2018.
URL : https://hal.archives-ouvertes.fr/hal-01880728

J. H. Yang, K. W. Song, Y. W. Lee, J. H. Kim, K. W. Kang et al., Microwave process for sintering of uranium dioxide, Journal of Nuclear Materials, pp.210-216, 2004.

S. Grandjean, A. Bérès, C. Maillard, and J. Rousselle, Procédé de coprécipitation d'actinides à des états d'oxydation distincts et de préparation de composés mixtes d'actinides, 2004.

V. Schneider and W. G. Druckenbrodt, Transactions of the American Nuclear Society, vol.40, pp.50-52, 1982.

V. E. Morkovnikov, L. S. Raginskiy, A. P. Pavlinov, V. A. Chernov, V. V. Revyakin et al., Plutonium Futures-the Science, Amer Inst Physics, p.199, 2000.

M. D. Eckenrode, An analysis of plutonium accountability in th COPRECAL process. Thesis submitted to the Faculty of the Virginia Polytechnic, 1985.

R. Faron and G. Schaal, Procédé d'obtention de trioxyde d'uranium par denitration thermique directe de nitrate d'uranyle, 1996.

S. Davied, R. Faron, and G. Schall, Procédé d'obtention d'un mélange d'oxydes métalliques pulvérulents, appartenant à la filière nucléaire, à partir de leurs nitrates, 1998.

R. J. Hobbs and P. Parkes, , 2000.

I. Toumanov, Plasma and High Frequency Processes for Obtaining and Processing Materials in the Nuclear Fuel Cycle, 2001.

D. Bykhovski, K. Guilbeau, J. Ibragimov, V. Saprykin, T. Thieblemont et al., , 2000.

K. Kumar, J. , S. Gunasekaran, S. Loganathan, G. Anand et al., The molecular structure, geometry, stability, thermal and fundamentalmodes of vibration of glycine dimer by DFT methods, Spectrochimica Acta Part A: Molecular andBiomolecular Spectroscopy, vol.115, pp.730-737, 2013.

A. Gómez-zavaglia and R. Fausto, Low-temperature solid-state FTIR study of glycine, sarcosine and N,N-dimethylglycine: observation of neutral forms of simple ?-amino acids in the solid state, Physical Chemistry Chemical Physics, issue.15, pp.3154-3161, 2003.

G. Fischer, X. Cao, N. Cox, and M. Francis, The FT-IR spectra of glycine and glycylglycine zwitterions isolatedin alkali halide matrices, Chemical Physics, pp.39-49, 2005.

Y. Horikawa, T. Tokushima, O. Takahashi, Y. Harada, A. Hiraya et al., Effect of amino group protonation on the carboxyl group in aqueous glycine observed by O 1s X-ray emission spectroscopy, Physical Chemistry Chemical Physics, issue.36, p.2018

Y. Gao and Y. Zhang, Formation and photochemical properties of aqueous brown carbon through glyoxal reactions with glycine, RSC Advances, issue.67, p.2018

L. C. Bichara, H. E. Lanús, E. G. Ferrer, M. B. Gramajo, S. A. Brandán et al., Vibrational Study and Force Field of the Citric Acid Dimer Based on the SQM Methodology, Effect of urea on the hydrolysis of Fe3+ ions in aqueous solutions at elevated temperature, vol.31, pp.43-48, 1997.

D. Maji, K. Ananthasivan, R. V. Krishnan, S. Balakrishnan, S. Amirthapandian et al., Nanocrystalline (U0.5Ce0.5)O-2 +/-X solid solutions through citrate gelcombustion, Journal of Nuclear Materials, vol.502, pp.370-379, 2018.

S. Kumar, D. , K. Ananthasivan, R. Venkata-krishnan, and A. Senapati, Reaction mechanism and kinetic analysis of citrate gel-combustion synthesis of nanocrystalline urania, J Therm Anal Calorim, vol.131, pp.2467-2476, 2018.