Nuclear power production is not at present in need of the extensive breeding of nuclear fuel. There are sufficient reserves of natural uranium. In addition, at the beginning of the twenty first century use will be made of surplus weapons material being released, highly enriched uranium and plutonium. However nuclear power production, which lays claim to replacing a substantial fraction of organic fuel, cannot exist without the breeding of nuclear fuel. Wide-scale nuclear power production in the twenty first century will require all nuclear fuel reserves to be activated, both uranium and thorium. Aiming for this policy and taking account of the time required for work to develop and master a new technology in nuclear power production it is necessary even now to begin to assimilate new fuel cycles. Considerable experience has been accumulated to date on the uranium-plutonium cycle which, from the start, was based on military programs. In the early days, thorium was also considered in military programs, but did not find application in them. Nevertheless, interest in it for nuclear power production is constantly being restored. A wide range of uses for thorium is proposed when considering it for nuclear power production, from the direct replacement of the fuel in operating power reactors to fundamentally new nuclear power schemes with the introduction of a reactor-accelerator combination and a fuel cycle with the depletion of actinides. Various possibilities have been considered for using thorium in VVI~R, RBMK, VTGR, fast, liquid-salt, and other reactors. Recently, along with the advantages indicated, the possibility has been studied of utilizing thorium in operating reactors or reactors under development in order to solve the problem of the nonproliferation of fissile materials. A version of a VVI~R reactor has been developed at the Kurchatov Institute Russian Scientific Center in which it will very shortly be possible to test and provide for the economic efficiency of thorium technology. The implementation of this concept will lower the risk of the proliferation of fissile materials, reduce the accumulation of radioactive waste, improve the practical efficiency of the thorium cycle, increase safety, supplement the fuel base, and deliver the possibility of utilizing surplus stocks of plutonium and uranium. NEW APPROACH TO INCORPORATING THORIUM IN NUCLEAR POWER PRODUCTIONInterest in thorium as a nuclear raw material arose from the first steps of the atomic era in view of the possibility of using it in order to obtain weapons 233U. However preference was given to highly enriched 235U and plutonium for military purposes.The characteristic features of thorium constantly draw attention to incorporating it into nuclear power production. The considerable natural reserves of thorium broaden the fuel base for nuclear power production and reinforce the preconditions for its wide-scale development. One of the principal problems of nuclear power production is that of guaranteeing the safe burial of the long-lived components of ...

The present status of the problems of safe storage and use of hydrogen in the world hydrogen-energy sector are analyzed. Specific examples of foreign and domestic designs of atomic-commercial complexes based on operating nuclear power plants, viewed as hydrogen producers and users, are presented. A method of producing hydrogen accumulators with cartridges which contain microcapsules or capillaries, made of highstrength materials and filled with hydrogen under high presure (above 100 MPa), is proposed as a promising direction for solving storage and use problems. The mechanisms of introducing/extracting hydrogen into/from microelements in the space of the accumulators up to a working pressure of 0.2-1 MPa are based on diffusion and active thermomechanical principles.The nuclear and chemical industries, automobile manufacturing industry, the aerospace complex, all forms of transportation (automobile, marine, and railroad), manufacturing of portable sources of power (mobile telephones, computers, everyday technology), and other industrial sectors are all showing great interest in high-quality and rapid development of hydrogen as a source of energy.Hydrogen power faces three basic problems: obtaining hydrogen by decomposition of water -electrolysis or thermolysis -or by the dissociation of hydrocarbons. The basic problems are to decrease the cost and direct conversion of the oxidation energy of hydrogen into electricity. This problem has already been solved technologically in our country and abroad with the assistance of various types of fuel cells, but the questions of their cost and service life, safe storage, and delivery to the consumer remain.Two basic directions of hydrogen production are being examined in the nuclear power industry: the development of atomic-commercial complexes based on high-temperature gas-cooled reactors and using the energy generated at nuclear power plants during a period of low demand.The design developed by the Russian Science Center Kurchatov Institute, the Leningrad nuclear power plant, and the Canadian companies AECL and Stuart Energy in 1990-1992 supposes that initially hydrogen is produced by electrolysis of water with power 30 MW, i.e., 14.5 tons/day. At the second stage of the design, the power of the electrolysis plant is to be increased to 300 MW. Electricity produced during a dip in the load on a nuclear power plant is to be used. At the Leningrad nuclear power plant, the underproduction during this period of time is approximately 400·10 6 kW·h/yr, which makes it possible to produce about 8000 tons hydrogen/yr. The hydrogen obtained is to be used for public transportation in Sosnovyi Bor and the excess hydrogen is to be sold to Finland. Another variant considered for utilizing the hydrogen obtained is to deliver it to the Kirishi petroleum processing plant. The oxygen obtained in so doing could become the basis for the production of ozone for purifying the industrial discharges in St. Petersburg [1]. Nuclear power plants can not only produce hydrogen; they are also hydrogen co...

Practical applications of atomic energy for military and civilian purposes started with the creation of research reactors. After the F-1 reactor was started up and atomic weapons were created, I. V. Kurchatov speeded up theoretical and experimental research at the Institute of Atomic Energy (IAE) on the development of research reactors designed for different purposes. The first integrated experimental base in the USSR for reactor tests and investigations of fuel elements and materials as part of the MR reactor and a hot materials-science laboratory was put into operation in April 1952, and the first water moderated and cooled reactor VVR-2, which operated on enriched uranium with a channel-free core and served as a prototype for the serially produced VVR-S reactors, was developed in 1954 at the IAE. The first water moderated and cooled swimming-pool research reactor IRT in the USSR was built in 1957 at the IAE.The IRT reactor with nominal power 1 MW was developed in the division of research reactors and reactor technologies; the head of the division and assistant to I. V. Kurchatov was V. V. Goncharov and the head of the design office was P. I. Shavrov. The head scientists responsible for the development of the IRT were V. V. Goncharov, Yu. G. Nikolaev, and Yu. F. Chernilin. The first director of the reactor was Chernilin. L. A. Goncharov calculated the reinforced concrete shielding for the reactor tank and for the lead-outs of the horizontal experimental channels. Physical startup of the IRT reactor occurred on November 26, 1957 under the direct supervision of A. P. Aleksandrov. All this occurred in the presence of F. Perren, who was the top atomic energy commissioner in France; this was specially recorded in the log book. V. M. Vertogradskii, B. G. Golubev, I. I. Larin, and A. F. Yashin, who were coworkers at the IRT, made a large contribution to the startup operations and utilization of the power capacities of IRT (up to 2 MW).The development of water moderated and cooled research reactors VVR-2 and the serially produced VVR-S and IRT reactors with capacity 2 MW was at that time an enormous scientific and engineering achievement of our reactor building capabilities. Kurchatov described in detail the construction of IRT and the experiments planned for it in his lecture "Nuclear Radiations in Science and Technology," which was prepared and delivered in June 1958 at the University of Albania (Tirana).Kurchatov wrote in this lecture: "During my student years the question of the source of the enormous, inexhaustible energy dissipated by stars and, specifically, by the sun into space excited scientists. The answer to this majestic cosmic problem was found in the then modest laboratories of physicists who were studying the structure of the smallest particles of matter -atomic nuclei.After Rutherford's remarkable discoveries in 1919, intensive study began of the interaction, splitting, and fusion of atomic nuclei. Gradually it became clear that the source of the stellar energy of space is precisely the energy released...

The objective of this conference was to exchange information and prepare further collaboration concerning the program of lowering the fuel enrichment of research and tests reactors.In 1994, a program for developing fuel elements and fuel assemblies for research reactors using fuel with 20% 235 U enrichment was initiated, which is part of the US program on lowering fuel enrichment used in research reactors. The Russian part of the program included the continuation of the development of fuel elements and assemblies for VVR-M2, IRT-3M, and MR with uranium dioxide fuel, development of high-density fuel, as well as fuel elements and assemblies of VVR-M5, IRT-3M, and IVV-10 reactors with such fuel [1].Development of IRT-4M Type Fuel Elements and Assemblies with Uranium Dioxide Fuel Enriched with 235 U to 19.7%. When decreasing the fuel enrichment to 19.7%, the 235 U content must be increased as compared with 36% enrichment fuel. To this end, in 1994 the Kurchatov Institute started the development of IRT-4M fuel assemblies, which are similar to IRT-3M assemblies, in which the widths of the fuel assemblies were increased from 1.4 to 1.6 mm, and the widths of the gaps between them were decreased from 2.05 to 1.85 mm, respectively. For this gap width, the water velocity in them will decrease by no more than 5%. The kernel thickness was increased from 0.4 to 0.7 mm, and the nominal cladding thickness is 0.45 mm, which is adequate for maintaining seal tightness [2]. For 400 g 235 U content in the eight-tube IRT-4M fuel assembly, the uranium content in the kernel is 3.85 g/cm 3 (Fig. 1).In May 1996, testing of individual size-types of fuel elements, perfected by the Novosibirsk Chemical Concentrates Works, as part of an experimental fuel assembly (Table 1) began in IR-8 without waiting for the technology for fuel elements of all sizes for IRT-4M fuel assemblies to be perfected. The tests were performed under the following conditions:

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