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Information × Registration Number 0205U007029, 0105U005731 , R & D reports Title Computer simulation of properties of LFCM interacting with atmosphere, water and aqueous solutions: mechanisms of interaction, materials of sorbtion-barrier type popup.stage_title Head Tokarchuk Mykhajlo Vasyl'ovych, Registration Date 08-12-2005 Organization Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine popup.description2 The report contains 223 pages of the typewritten text and will consist from the introduction, ten sections of the basic part and the list of the literature from 165 names. In the report 67 figures and 11 tables are given. The purpose given research effort is: computer model operation of behaviour LFCM at interaction with an atmosphere, water, aqueous solutions and development of computer-adapted physicochemical model which would take into account the basic mechanisms of processes, including radiation - diffuse, the adsorption, destructive, an oxidizing both other; synthesis and examination of sorbtion materials on the basis of oxides of metals put on a clayey matrix for deactivation of fluid radioactive waste of lixiviation LFCM. The analysis of major factors which define state of LFCM at interaction with an atmosphere and aqueous solutions of radioelements is lead. The analysis of results of new experimental researches mechanical, electrical, magnetic, etc. properties is given. It is shown, that thebasic mechanisms of fracture irradiated fuel (IF) at an oxidizing is adhesion grains and cracking of a surface of separate grains at formation of phase U3O7/U4O9, and the screes of nonuniform clusters of an exterior seam at formation of phaseU3O8. It is lead estimates of velocities of these processes and requirements of fracture IF. It is shown, that the oxidizing of fuel inserts in LFCМ also can be one of the important factors of their fracture. With the help of quantum-chemical calculations (the method ab-initio) is explored process of an adsorption of caesium and strontium in structural pores of silicates and aluminosilicate and also process of an adsorption of uranyl on a surface of silicates in view of presence of a hydrated shell of uranyl. It is optimized structure of system an adsorbate - adsorbent, places of localization of radionuclides set, the detailed information on allocation of charges and distances between atoms to an adsorbate and sorbent is received, bonding force are designed. It is received, that for intromission deep into pores of silicate ions of radionuclides should overcome a potential hill which for caesium the much greater is than for strontium. It set, that at examination of an adsorption of uranyl on a surface of aluminosilicate it is necessary to take into account presence of molecules of water at a hydrated shell of uranyl. With the help of a method of molecular dynamics loudspeaker examination of water and an aqueous solution of ions of the uranyl adsorbed in pores of a silica gel is lead. In given explored the trajectory of the solution of a problem of the bound with studying aqueous solutions of radionuclides in disorder is offered to a porous medium of type a silica gel. The presented model in integrating with a method of the molecular allows to describe dynamic loudspeakers realistically bodily both structural, and dynamic properties of molecules of water and ions of uranyl in disorder pores of silicates. We design a series of structural performances for water in nanoskope poresof a silica gel and features of interaction of an ion of uranyl with water and a surface of pores of silicate are analysed. It is shown, that an output{exit} of complex UO3-HCO3-in a solution together with processes oxidation, hydrations, and also a hydrolysis - oxygen grid LFCM with an output in solution Si-O, Si-OH, Si (OH)4, Si (OH) 62-, наночастиц Si- O-Ca-O-Si, Si - O-UO2-O-Si, Si O-Pu2-O-Si it is possible to consider silicium as process of microdisolution of surface LFCM. It is received reactionary - diffuse transport equations of mass, a charge, streams of a charge, a stress tensor as composite physical прогнозной models of treatment FCM within the framework of model of the description it is radiation - boosted processes, the physicochemical model of interaction with aqueous solutions during lixiviation LFCM. With application of macroscopic methods of physics of surface the thermodynamic model which features disproportionation of electric charges and mechanical voltages in callows of solid bodies (devices LFCM) which are exposeed a radiative self-irradiation and thermal-cycle factors designed, and also interreact with aqueous solutions of radioelements. The design procedure of energy of adhesive bond and operations of an adhesion designed in view of interphase energies and a tension accordingly. Character of relations between electrical and mechanical composite energy interphase and adhesiveness parameters of contacting systems is explored. On the basis of the lead theoretical calculations and experimental researches designed a tailored composition of sorbtion-barrier materials. It set, that presence of a carbonaceous component gives practically the unbounded opportunities for inoculation of a surface of a clayey mineral. Synthesized ferrocyanide sorbtion materials and samples of the modified oxyhydroxides Fe3 +, Al3 +, Ti4 +, Sb5 + carbonatecontaining montmorillonite clay are superfine powders and easily swell in water. Most efficiently they can be utilised for a sorption of radionuclides in static conditions. Their getter properties merge getter ability of montmorillonite and natural oxide-coated minerals. From the point of view of the sorbtion-selection properties (behind caesium) the optimal is copper - potassium containing the sorbtion ferrocyanide materials put on a clayey matrix. Laboratory batches of sorbtion materials of a different composition are synthesized with the purpose of their further approbation during deactivation of actual fluid radioactive waste. On the basis of improved procedures of synthesis of laboratory batches of sorbtion materials it designed the key flow diagram and a production schedules of their reception. The analysis of physical methods of reception of finely divided particles of oxides of metals and opportunities of their use for a sorption of radionuclides in solutions of radioactive waste of lixiviation LFCM is lead. The procedure of reception of sorbents designed on the basis of particles of oxides of metals and the pilot unit for synthesis of finely divided particles of oxides of metals is manufactured by incineration of metals in a laminar diffuse torch. The disperse analysis of particles of the iron oxide received by the gas-dispersed method of synthesis is lead. 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