Soviet Atomic Energy - Vol. 38, No. 1

Body: Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 , \ ? ( Russian Original .Vol. 38, No. 1, January, 1975 SATEAZ 38(.1) 1-88 (1975), SOVIET ? ATOMIC ENERGY rc q)) ATOMHAA 3HEPrI1R (ATOMNAYA iNERGIYA) TRANSLATED FROM RUSSIAN , CONSULTANTS BUREAU, NEW YORK . ? Declassified and Approved For Release 2013/09/25: CIA-RDP16-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 SOVIET ATOMIC ENERGY Soviet Atomic Energy is abstracted or in- dexed in Applied Mechanics Reviews, Chem- ical Abstracts, Engineering Index, 1NSPEC? Physics Abstracts and Electrical and Elec- tronics Abstracts, Current Contents, and Nuclear Science Abstracts. Soviet Atomic Energy is a cover-to-cover translation of Atcmnaya Energiya, a publication of the Academy of Sciences of the USSR. An agreement with the Copyright Agency of the USSR (VAAP) makes available both advance copies of the Russian journal and original glossy photographs and artwork. This serves to decrease the necessary time lag between publication of the original and publication of the translation and helps to improve the quality of the latter. The translation began with the first issue of the Russian journal. Editorial Board of Atomnaya Energiya: Editor: M. D. Millionshchikov Deputy Director I. V. Kurchatov Institute of Atomic Energy Academy of Sciences of the USSR Moscow, USSR Associate Editor: N. A. Vlasov A. A. Bochvar N. A. Dollezhal' V. S. Fursov I. N. Golovin V. F. Kalinin A. K. Krasin A. I. Leipunskii V. V. Matveev M. G. Meshcheryakov P. N. Palei V. B. Shevchenko V. I. Smirnov A. P. Vinogradov A. P. Zefirov Copyright C) 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. All rights reserved. No article contained herein may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. Consultants Bureau journals appear about six months after the publication of the original Russian issue. For bibliographic accuracy, the English issue published by Consultants Bureau carries the same number and date as the original Russian from which it was translated. For example, a Russian issue published in December will appear in a Consultants Bureau English translation about the following June, but the translation issue will carry the December date. When ordering any Volume or particu- lar issue of a Consultants Bureau journal, please specify the date and, where appli- cable, the volume and issue numbers of the original Russian. The material you will receive will be a translation of that Russian volume or issue. Subscription $87.50 per volume (6 Issues) Prices somewhat higher Outside the United States. Single Issue: $50 Single Article: $15 CONSULTANTS BUREAU, NEW YORK AND LONDON 227 West 17th Street New York, New York 10011 4a Lower John Street London WI R 3PD England Published monthly. Second-class postage paid at Jamaica, New York 11431. Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 SOVIET ATOMIC ENERGY A translation of Atomnaya tnergiya July, 1975 Volume 38, Number 1 January, 1975 Recipients of the 1974 State Prize for the Design and Building of the VVER-440 Line of CONTENTS Engl./Russ. Reactor Facilities for Nuclear Power Stations 1 2 ARTICLES Ten Years of Operating Experience at theUSSR Fiftieth Anniversary Nuclear Power Station at Novovoronezh ? A. N. Grigortyants, F. Ya. Ovchinnikov, V. K. Sedov, L. I. Golubev, Yu. A. Akkuratnov, I. V. Prokopenko, I. I. Kustov, N. A. Isakov, V. D. Dobrynin, A. V. Tsybul,nik, and V. I. Skrypnikov 2 3 Effect of Temperature Distribution on the Swelling of UO2 and UO2?Pu02 Cores ? V. I. Kuz,min and I. G. Lebedev 10 11 BOOK REVIEWS N. I. Chesnokov, A. A. Petrosov, and A. A. Vinogradov. Optimization of Solutions (Decisions) in the Development of Uranium Sites ? S. Ya. Chernavskii 15 15 ARTICLES Hydraulic Resistance in Channels with Surface Boiling ? V. A. Knyazev 16 16 BOOK REVIEWS t H. Muller, K. Meyersberger, and H. Sprinz. Special Methods of Analyzing Stable Isotopes ? L. I. Petrenko 21 19 ARTICLES Influence of Low-Temperature Irradiation on the Phase Composition of Uranium Alloys Containing Small Quantities of Aluminum and Iron ? Yu. V. Bobkov, I. A. Naskidashvili, V. V. Petrosyan, and Yu. N. Sokurskii 22 20 Radiolysis of Solutions of TBP in Contact with Nitric Acid. II. Processes of Oxidation and Nitration ? E. V. Barelko and I. P. Solyanina 25 -'' ' 23 ---- On the Magnitude of the Magnetic Field Produced in a Laser Plasma ? A. F. Nastoyashchii 30 27 Parameters of the Neutron Resonances of 241Am in the Energy Range from 8 to 30 eV ? T. S. Belanova, A. G. Kolesov, V. M. Nikolaev, V. A. Safonov, V. Ya. Gabeskiriya, V. A. Poruchikov, S. M. Kalebin, R. I. Ivanov, and 0. M. Gudkov 33 29 ?ABSTRACTS Recovery of Neutron Spectrum by the Method of Simulated Spectra Using Set of Threshold Detectors ? G. M. Obaturov and A. A. Tumanov 38 35 Rating of the Capabilities of Photoneutron Installations for Determining Deuterium Concentration Utilizing SNM Counters ? R. P. Meshcheryakov, S. V. Popov, and E. S. Solodovnikov 39 36 Monte Carlo Calculation of the Distribution of Electron-Beam Energy Absorbed in Matter ?A. M. Zlobin, E. N. Donskoi, and V. V. Khizhnyakov 40 36 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 CONTENTS (continued) Engl./Russ. Consideration of the Decay and Accumulation of Mixtures of Genetically Related Short-Lived Isotopes in y -Spectral Analysis - Yu. A. Zaitsev 41 37 LETTERS TO THE EDITOR Application of Albedo Equations - V. V. Orlov 42 39 Distribution of Fast Neutrons in Iron-Water Shielding - D. L. Broder, K. K. Popkov, V. G. Taxoev, I. N. Trofimov, and S. A. Tsvetkova 44 40 Dose Distributions in Phantoms outside 1-1000-GeV Accelerators - N. V. Mokhov, E. L. Potemkin, and V. V. Frolov 47 42 Measurement of gf(239po/af(2350 and crf(233U)/o-f(235U) Fission Ratios at 2 keV - V. G. Dvyldisherstnov, V. L. Petrov, and V. M. Furmanov 49 43 Fast Neutron Spectrometry of (04 n) Reactions Using a Deuterated Scintillator - E. M. Burymov, S. P. Korsunova, and N. N. Spendiarov 52 45 Initial Static Focusing in Small Linear Traveling-Wave Accelerators - A. D. Vlasov. . . 54 -N 46 Dependence of the Fission-Fragment Sputtering Ratio for Thin Layers of a Substance on the Mean Energy of the Fragments - B. M. Aleksandrov, N. V. Babadzhanyants, I. A. Baranov, A. S. Krivokhatskii, L. M. Krizhanskii, and V. V. Obnorskii. 57 47 Silver Chloride Track Detectors - N. P. Kocherov, N. R. Novikova, and N. A. Perfilov. 60 49 Change in the Optical Density of PMMA under the Action of Deuterons with Energies 4-150 keV - S. P. Kapchigashev, V. P. Kovalev, E. S. Baridaatov, and V. A. Sokolov 62 50 COMECON NEWS Provisional International Workteam - P. M. Tyulditin 64 51 Collaboration Daybook 65 51 INFORMATION: CONFERENCES AND MEETINGS The Ninth World Energy Conference - Yu. I. Koryakin 68 53 Intensified Heat Transfer in Channels of RBMK Type Reactors - A. N. Ryabov and V. N. Filippov 73 56 The Second All-Union Conference on the Metrology of Neutron Radiation at Reactor and Accelerator Facilities - R. D. Vasiltev 76 58 MIFI Twenty-Sixth Scientific Conference Held - V. V. Frolov and V. A. Grigortev . 78 59 The Fourth All-Union Plasma Physics School - V. A. Papadichev 80 60 INFORMATION: SCIENCE AND ENGINEERING LIAISONS Familiarization Trip by Soviet Specialists to Sweden - A. D. Amaev. . 83 61 BOOK REVIEWS New Books from A tomizdat 86 63 The Russian press date (podpisano k pechati) of this issue was 12/23/1974. Publication therefore did not occur prior to this date, but must be assumed to have taken place reasonably soon thereafter. Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 RECIPIENTS OF THE 1974 STATE PRIZE FOR THE DESIGN AND BUILDING OF THE VVER-440 LINE OF REACTOR FACILITIES FOR NUCLEAR POWER STATIONS G. L. Lunin E. S. Chernorotov V. F. Ostashenko V. V. Stekoltnikov V. P. Denisov A. B. Sukhov N. I. Gorelov P. M. Verkhovykh N. M. Kantiev L. M. Voronin V. K. Kalashnlkov A. T. Glushkov Translated from Atomnaya Energiya, Vol. 38, No. 1, p. 2, January, 1975. ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 ARTICLES TEN YEARS OF OPERATING EXPERIENCE AT THE USSR FIFTIETH ANNIVERSARY NUCLEAR POWER STATION AT NOVOVORONEZH A. N. Grigortyants, F. Ya. Ovchinnikov, V. K. Sedov, L. I. Golubev, Yu. A. Akkuratnov, I. V. Prokopenko, I. I. Kustov, N. A. Isakov, V. D. Dobrynin, A. V. Tsybultnik, and V. I. Skrypnikov UDC 621.311.2:621.039 The Novovoronezh nuclear electric power generating station went into operation on September 30, 1964, when the first experimental full-scale power-generating mit, rated 210 MW(e), began to feed current into the national grid. The Novovoronezh nuclear power station is the largest nuclear electric power generating plant built in our country. The total ratings of its four nuclear power generating units total 1455 MW(e). Construction work on the NVAES (Novovoronezh nuclear power station) has been proceeding at accelerated tempos. The first power generating unit with its VVER-210 reactor was built in the space of 7.5 years; the second power generating unit with its VVER-365 reactor went on the line in 1969, a mere 5.5 years since ground was broken for the plant. The principal quantity-manufactured power generating units with their VVER-440 reactors were installed and put into service in even shorter periods of time. The building of the third and fourth power generating wilts was begun in 1968, and construction work was completed within less than five years, with a one-year offset, the third being completed in 1971 and the fourth in 1972. The equipment of the fourth power generating unit was installed within one year at most. The construction program for the first echelon of the NVAES power station was completed successfully when the fourth power generating unit began generating power for the national grid. Startup and adjustment operations were carried out in stages, so that adjustment of subsystems could be attended to several months in advance of the completion of installation and rigging operations, to be followed by comprehensive adjustments of overall equipment and entire systems. This method was relied on for startup of several other nuclear power stations, such as the Kola station, the Nord power station (in GDR), the Kozlodui power station (in Bulgaria), and others. In addition to the speedup in construction, installation, rigging, and startup and adjustment opera- tions, the lead time for installation of capacity following the physical startup and power startup was also shortened. This was particularly striking in the case of the quantity-manufactured units with VVER-440 reactors. The scheduled year-long period was cut down to six months when the third power generating unit went on the line, and that period was cut down to a mere 83 days in the case of the fourth power gener- ating unit. Engineering cost indices for the power station (see Tables 1-3) have been continually improved in the process of putting the plant into operation and expanding it. Versatility of the Novovoronezh Nuclear Power Station. The power station operates as an integral part of the Voronezhenergo power grid, mainly at base load with a slight drop in load at the end of the week and on holidays or off-days, when the number of industrial consumers of electric power decreases Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 3-10, January, 1975. Original article submitted September 30, 1974. 2 ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 TABLE 1. Characteristics of NVAES Basic Power Equipment Equipment _ 1st power genera- ting unit 2nd power genera- ting unit 3rd and 4th power generating units Reactors type VVER-210 VVER-365 VVER-440 thermal power, MW 760 1320 1375 weight of pressure vessel, tons 185,4 209,2 200,8 dimensions of pressure vessel, m 4,4x11,1 4,4x12 4,27 x 11 ,8 operating coolant pressure, ligt/cm2 100 105 125 Steam generators capacity, tons/h 230 325 455 saturated steam pressure, kg/cm2 32 33 47 heat transfer coefficient, k irri2??C 4,29 4,37 4,32 heat transfer surface area, m? 1290 1800 2500 U-tube diameter, mm 21x1,5 16x1,4 16x1,4 number of tubes 2774 3664 5146 dimensions of steam generator, m Main circulation pumps 3,06x11,57 3,07x11,57 3,27x11,99 type GTsgb1 -138 GT5EN-3 09 GTsgN-310 power intake, kW 1650 1530 2260 capacity, m3/11 5250 5600 7000 head, kgf/cm average duration of maintenance-free operation, h 4 5000 5 20 000 , 5 15 000 * Turbogenerators output, MW 70 73 220 number 3 5 2 'From the time the third power generating unit was started up. A constant shortage of electric power in the grid imposes stringent limitations on the length of reactor fuel reloading shutdown periods, which occur in spring and summer months for the most part. In some instances, particularly during the autumn and winter peak loads, a need is felt to stretch the in-pile time of the fuel loading by cutting down on power output toward the end of the reactor campaign. Operating the reactor on power effect lowers the fuel component of the net power costs. But a de- crease in the amount of electric power generated and an increase in the capital component of the net power costs restricts the time over which operation under that set of conditions can be justified economically. When heightened wear on the equipment as the power generating unit is operated at reduced power output levels is taken into account, we see that reliance on power effect must be treated as both forced and provisional. Dynamic tests showed the reactors exhibit excellent self-regulating properties in the face of such major disturbances as tripping out of one or several main circulation pumps, outing of the turbogenerator by disconnection from the power line, and so on. The self-stabilization capability of the reactor eases the transition to the on-power level corresponding to the new allowable operating conditions. Some experience has already been acquired at the power station in altering the power output of the power generating unit over the course of a full day in order to cover the morning and evening peak loads in the power system. For example, the second power generating unit operated under that set of conditions throughout January of 1972. The power output of the power generating unit was maintained at the rated level every day during the morning and evening hours of peak demand, and cut back 30% at nighttime during that period. The degree of adjustability of the nuclear power station is also characterized by the comparatively short time it takes to bring the power generating unit up to full power after a prolonged shutdown period for cooldown of the primary loop. The total time it takes to carry out a thoroughgoingcomplex checkout of the reactor control and emergency protection system, to attain the primary loop parameter ratings, to heat up the turbogenerators and synchronize them with the overall system, amounts to 15 h more or less. The same time is required for reactor cooldown and to adjust the reactor to the appropriate state for maintenance and repair operations. The operating stability of the power station is of exceptional importance for normal electric power supplies to the consumers. The stability exhibited by the NVAES is demonstrated to be quite high by the data entered in Table 4. The total number of shutdowns experienced by the third, second, and fourth power generating units over the 1970-1973 period was 57. The bulk of these shutdowns (43 out of the 57) took place while the power generating units were being adjusted and run through their first paces. Once adjusted to power level, the power generating units have been operating with excellent stability. 3 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Fig. 1. Novovoronezh nuclear power station. General view of third and fourth power generating units. ? Fig. 2. Novovoronezh nuclear power station. Construction work on the fifth power generating unit. Basic Power Equipment. Reliable performance on the part of the basic power equipment is respon- sible for the high operating stability of nuclear power stations. The power station staff and personnel care- fully studies the performance characteristics of the equipment and the technological flowsheets, and selects optimum operating conditions. As demonstrated by separation tests and thermal hydraulics tests carried out in collaboration with the F. E. Dzerzhinskii VTI, steam generators satisfy the necessary requirements in terms of steam quality and steam capacity. But isolated cases of tube failure were observed in two steam generators (the No. 3 steam generator in the first power generating unit and the No. 9 steam generator in the second power generating unit). The failed pipes were blanked off in order to eliminate any leakage of primary-loop radio- active water into the secondary loop. 4 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 TABLE 2. Engineering Cost Data on Power Generating Units ? Indices 1st power generating unit 2nd power generating unit 3rd power 14th generating !generating unit power unit Electric power output. MW 210 365 440 440 Year construction was begun 1957 1965 1968 1969 Specific capital investments, rubles/kW 326 256 200 200 Physical startup XII 1963 XII 1969 XII 1971 mi 1972 Power startup IX 1964 XII 1969 XII 1971 XII 1972 Power rating achieved XII 1964 IV 1970 VI 1972 IV 1973 Gross efficiency of power generating unit 27,6 27,6 32,0* 32,0* In-plant power needs CP of power rating) 8,0 7,3 6,8 6,8 Total electric power generated by. 1974", million kWh 9193,1 8487,7 4010,5 2790.6 Planned output of electric power in 1974, million kWh Annual installed power utilization factor achieved by 1357 2671 2945 2577 1974 0,87 0,81 0,55 0,72 Annual electric power net costs attained by 1974, kopeks /kWh 0,925 0,643 0,834 0,716 Ti??irt?TiiTe condenser pressure 0.035 atm. TABLE 3. Engineering Cost Data for NVAES Power Station Operation 1971-1975 Indices 1971 1972 1973 1974 (planned) 1975 (planned) Electric power generated, million kWh 2027,2 5413,4 8674,7 9550 9900 Electric power net costs, kopeks/kWh 0,948 0,810 0,752 0,66 0,65 Installed power utilization coefficient 0,633 0,607 0,681 0,753 0,776 Operating experience with the steam generating units has demonstrated clearly that deposits on the pipes, on the secondary-loop side, are of an oxide nature, are readily removable, and do not affect the heat-transfer process. But rigid standards must be imposed on secondary-loop water management in order to keep the pipes in good working condition. For example, feedwater for the steam generators was excessively high during the first reactor campaign of the third power generating unit, because of the unsoundness of some of the turbine condensor pipes. As a result, investigations carried out during fuel reloading revealed, the piping suffered extensive contamination due mainly to iron oxides, so that the steam generators had to be blown down. The water management regulations were revised to facilitate removal of contaminants from the piping. A limiting hardness of 0.1 mg-equiv. was set, with turbines outed immediately for repair and maintenance work on the pipes in the event that level was exceeded. Special condensate cleanup systems for the secondary-loop water were proposed for the future, as is the situation at most fossil-fuel electric power generating stations. While the first power generating unit was in service, some shortcomings in the design of the main circulation pumps deemed responsible for several unscheduled shutdowns were corrected. The various subsystems of the pumps were redesigned and modernized, and the tubing arrangement entering the self- contained cooling system for the bearings was simplified, so that the impeller system could be changed with the object of minimizing fluctuations in head, and the stator blading cooling system was centralized. At the present time, the obsolete GT5EN-138 pumps on stream in the first power generating unit have been replaced by the more sophisticated GT5EN-309 pumps employed in the second power generating unit. A technique of vibratory acoustic diagnostics worked out by the NVAES staff has been in use to monitor malfunctions of the main circulation pumps. Acoustic transducers have been installed on the pumps, and secondary instruments have been located on the reactor control panels. The method in question aids in pinpointing typical pump malfunctions such as excessive wear on bearings, beating of the rotor on the casing, and so on. Operation of 70 MW turbogenerator sets installed in the first and second power generating units of the power station has demonstrated the possibility of stepping up the power output of each turbogenerator set to 80 MW without any deterioration in efficiency. The unit power output of the turbines in the third and fourth power generating units has been increased to 220 MW. The use of high power rating sets and the increase in the performance parameters of the coolants has made it possible to obtain better perfor- ? mance per cost from the power generating units. Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 TABLE 4. Data on NVAES Operating Stability Indices Before attaining power rating After attaining power, rating 2nd power genera- ting unit 1970 3rd powei genera- ting unit 1972 4th power genera- ting unit 1973 2nd power generating unit 3rd unit 1971 1972 1973 1973 Number of shutdowns of power generating units and electric power not generated in 10 kWh) because of equipment malfunc- 9 25 9 6 2 1 5 tions 222,4 220 55,7 81,4 1,6 19,8 86,0 Number of shutdowns of power generating units and electric power not generated (in 106 kWh) because of personnel judgment 2 5 . 2 None None errors 0,7 2,0 0,4 0,3 0,5 Length of time power generating unit on power, h 5651 7120 8072 5761 7884 7849 7123 It took the combined creative efforts of the power plant operating personnel and of the personnel of the manufacturing plant to put these new turbines into service. The operation of the nuclear power station turbines working on saturated steam demonstrated the importance of the problem of coping with erosion, a severe problem for the turbine components. Specifi- cally, erosion wear on components of the turbine flow passages in the third power generating unit turbines was detected, and the unit had to be shut down for an additional period to effect repairs and eliminate the problem. Work was begun, in collaboration with the personnel of the turbine manufacturing plant, on im- proving the performance of the NVAES turbines by selecting and testing wear-resistant materials service- able in the manufacture of turbine components, in plating turbine components, and in hardfacing those components when buildup is called for during repair and maintenance work. A first-stage rotor blade of the high-pressure cylinder broke off while the third power generating unit was being run up to full power, and the noZzle guide vanes of the No. 9 turbine were ruined. The shank of a rotor blade in the No. 10 turbine was discovered overstrained. Replacement of the blades caused a two-month shutdown of those turbines. The insufficiently stable performance of the turbines was due in large measure to the frequent damage suffered by the brass piping of the condensers. As investigations revealed, the reason for this damage was the inadequate resistance to corrosion on the part of the piping material. At the present time, preparatory studies are underway at the power station on how best to replace this piping with other piping presenting improved resistance to corrosive attack. The design of the reactor control and protection components underwent some changes while the reactors were in service, with modifications introduced by designers varying from one power generating unit to the next depending on the experience accumulated and the uranium fuel enrichment being increased to 3.6%. The number of assemblies of electromechanically controlled control and protection systems was increased from 37 to 73 in the second, third, and fourth power generating units, and all of these assem- blies combine the functions of control and scramming, so that the number of fuel assemblies could be increased from 343 to 349 with scramming speed retained, and with enrichment of the fuel charge as an added benefit. A system of fluid control of reactivity with the aid of boric acid has been instituted starting with the second power generating unit, so that the power distribution throughout the core can be improved and so that the electromechanical control and protection system can be backed up by a liquid scramming feature. A rack and gear drive is being used in the power drives of the control and protection assemblies in the third and fourth power generating units, in place of the earlier screw and ball nut kinematic pair, and that has improved the speed characteristics of the power drives while enhancing their reliability. In addition, automatic controllers (known as pulsed power controllers) tracking the parameters of the primary and secondary loops and responding to any changes in those loop parameters have been introduced into the systems of these power generating units. The pulsed power controllers also have the job of automatically lowering reactor power output when several main circulating pumps shut off. All scramming signals were divided into four distinct categories in terms of degree of hazard, in the operation of the first power generating unit. In this protection arrangement, a complete shutdown of the reactor through the simultaneous actuation of all of the control rods released downward would come about only in instances where the heat-transfer reliability of the core deteriorated severely (e.g., tripping out of main circulating pumps, an abrupt rise in reactor power output level, total dumping of turbine loads, and the like). In any remaining cases, reactor power output would be lowered in response to a protection signal Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 through sequential downward displacement of groups of control rods, to be terminated with the disappear- ance of the protection signal. This improvement made it possible to cut down appreciably on downtime due to actuation of the reactor protection system. On the whole, the control and protection system fulfilled its functions reliably in proper response to stimuli. A procedure for maintenance of the equipment serving \TITER radioactive loops has been instituted at the NVAES power station, and experience of great practical value has been accumulated in the process. Inspection and maintenance technology for the reactor pressure vessel has been mastered for the first time following a protracted service period, and this technology covers the pipe outlets for the principal process pipes, the sheathed tubing of the power drives from the control and protection system assemblies, and also the reactor innards (in-pile equipment and devices). Reactor inspection in a program calling for complete unloading of the reactor core and extraction of all of the innards from the reactor of the first power generating unit was executed for the first time in the 1970-1971 period. This breakdown inspection required the creative efforts of the entire staff for working out a suitable repair and maintenance technology, methods of monitoring and inspection, devising protec- tive devices and custom-engineered fixtures and accessories for remote-controlled in-pile operations, learning new metal-working techniques (in particular plasma cutting, electric-arc cutting, and electric erosion cutting of metals), including cutting of metals under water with the aid of carbon electrodes. A biologically shielded container equipped with handholes and windows covered with special grades of glass was designed and built to aid in inspection and repair of the reactor pressure vessel. Closed-circuit tele- vision arrangements were employed liberally in inspecting equipment sets located in inaccessible and difficult-to-get-at sites. As a rule, all of the repair, maintenance, and inspection operations were tried out first on mockups simulating the actual conditions. Before this inspection and repair work was begun, the primary-loop equipment was deactivated by applying special solutions. Inspection of the reactor in the first power generating unit revealed some serious shortcomings in the design of the reactor innards, which exhibited inadequate strength and inadequate resistance to vibra- tion in the coolant stream. The new in-pile equipment, like the in-pile equipment in the other new reac- tors of this nuclear power station, exhibit heightened ability to withstand vibrations, and feature modular design which renders the job of monitoring and inspection easier. Cracks were detected on the adapters of the main pipe connections in the process of inspecting the pressure vessel, and this led to the develop- ment of a technology for inspection and repair of pipe connections which was implemented for the first time in this program. Adapters made of 1Kh18N1OT grade steel were inserted and welded in place. The adapters were press-fitted after cooling in liquid nitrogen, by using a special auxiliary fixture with a pneumatic power drive developing 3 tons of force. In 1971, the in-pile equipment of the reactor in the second power generating unit was extracted and inspected in a similar repair and maintenance program, because of the rupturing of one of the quieting tubes in the control and protection assemblies. All of the innards of the reactor in the fourth power gener- ating unit were extracted in April, 1974, at fuel reloading time, for a shakedown inspection of the reactor pressure vessel. Periodically scheduled inspections of reactor pressure vessels are on the agenda for all the power generating units of the power station in future practice. Defects in the weldments joining the sheathed tubes of the power drives of control and protection system assemblies to the cover of the reactor pressure vessel were detected while the first power gener- ating unit was in service, where the primary-loop hot water became mixed up with cold water fed into the sheathes to cool the electric motors of the power drives. Thermal stresses generated in the metal con- tributed to the appearance of flaws at those sites. After a special maintenance technology had been worked out in 1967, the welded joints were replaced by flanged joints. This redesigning effort was also required on the reactor of the second power generating mit in 1970. Operating experience with the mechanisms and moving parts of the control and protection system serving the first power generating unit was incorporated in the design of the VITtR-440 reactors of the third and fourth power generating units. Flanged sheath joints were provided in those reactor assemblies, and the electric motors of the power drives are cooled in these cases with the aid of a special intermediate loop. A change in the design of some components of the electromechanical control and protection system improved system performance. But since the presence of pulsations and temperature gradients affects the operating characteristics and the state of the metal, designers are obliged to take into cognizance the operating experience acquired with that system for attention to further improvements. 7 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 A technology developed for replacing the primary-loop main circulating pumps was first worked out at NVAES power station. With the active participation of the power plant personnel, a repair and main- tenance machine shop was designed and built for the upkeep of main circulation pumps, with equipment for deactivation, specialized ventilation, and all necessary accessories on hand. Equipment maintenance experience accumulated over the 1964-1971 years with the first and second power generating units made it possible to carry out successful redesign work needed while the power generating unit was being put through its paces and put into service, and in the work on the quantity-manu- factured power generating units incorporating VVER-440 reactors. One of the crucial operations mastered in practice at the NVAES power station is reloading of nuclear fuel, usually combined with inspection and maintenance of power equipment. The power generating unit is shut down for short periods (ranging from 25 to 30 days) for fuel re- placement, and involves such complex operations as failure of bonding in the primary loop, withdrawal of spent fuel assemblies, and installation of new fuel assemblies. The characteristics of the new fuel loading are calculated teqtatively on computers. The loading is done in such a way that the required dura- tion of the next reactor campaign is rendered possible, and the acceptable physical parameters limiting the reactor power output level are attained. Special attention is given to nuclear safety considerations in the refueling process and to the performance of the new core. As a rule, reloading of about one third of the fuel assemblies in each reactor is carried out once a year, during the summertime. But the presence of four functioning power generating units imposes additional time restrictions, since refueling requires serious preparation. The refueling operations proceed parallel with monitoring of the soundness and leak- proofing of fuel element cans in operating fuel assemblies, with the aid of special techniques worked out at the power station. The method based on measuring the degree of radioactivity of the air in which self- heating of a fuel assembly deprived of water occurs is the method most widely relied on in practice. Air activity increases when flaws are present in the fuel element can through which gaseous and volatile fission products can exit. "Leaky" assemblies are replaced; the makeup of the fuel charge is corrected and the design characteristics of the reactor core are also corrected appropriately. The fuel is reloaded underwater, in all of the power generating units of the nuclear power station except for the second power generating unit, by special machines designed for the purpose, and that ensures complete safety when appropriate dosimetric health physics monitoring is attended to. In the second power generating unit, the spent fuel assemblies are conveyed to a storage tank in a special shielded container. A liquid neutron absorber, boric acid added to the water of the primary loop, is relied on to maintain the deep subcriticality of the reactor during the refueling process. The neutron flux in the reactor is monitored by a special refueling auxiliary system with sensitive ionization chambers installed in the channels of the faceted belt in the reactor support cage. Research work and pilot tests continually staged at the NVAES power station help, in addition to scientific-research work and planning and design work carried on by institutions dedicated to those pur- poses, in shortening the time required for successful adaptation and improvement of the basic equipment and improvement of engineering cost figures. Among the most important results achieved are something little short of doubling the power rating of the newly intrOduced reactors without any increase in core size, and by the same token without any increase in the size of the reactor pressure vessels. This became possible through improvements in the power dis- tribution over the core as a consequence of working out a liquid control schedule first implemented in the second power generating unit. Simultaneously, a ilowsheet and a technology for normal and scrammed introduction of boric acid into the primary loop, plans for extraction of the boric acid, and plans for clean- up of loop water and proper water management, were worked out. A modification of the fuel grid with the dimensions of the fuel assemblies left unaltered made it possible to increase the number of fuel ele- ments, and consequently to increase the average energy yield per fuel element with the maximum allow- able load at which there would be no meltdown of the uranium dioxide in the center of the fuel element core retained. There are 12 special measuring channels in the central tubes of the reactors in the third and fourth power generating units, and five such channels in the second power generating unit, for measuring varia- tion factors in power generation over the core height. The neutron flux distribution in the channels is measured by activation detectors or direct-charging sensors. At the present time, the possibility of automating in-pile measurements with the use of direct-charging sensors and data processing through a M-6000 computer is under study at the power station. 8 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Methods for monitoring the state of fuel elements present in the reactor core were worked out and perfected while the power generating units were in service. In addition to radiochemical monitoring based on the degree of fission-fragment activity on the part of the primary-loop water in the first power genera- ting unit, a system designed to take continuous recordings of the background level of delayed neutrons in circulation subloops has also been worked out for the first power generating unit. The system demon- strated its feasibility and has been instituted in all of the power generating units of the nuclear power station. Radiation Safety. Under normal operating conditions, even when several leaky fuel elements turn up in the core, the total activity of water is not greater than 10-4 to 10-3 Ci/liter. A sufficiently low level of activity and a high degree of leak-proofing of the primary-loop equipment can ensure a low level of radioactive contamination of the nuclear power station rooms, and also can place limits on the amount of gaseous and aerosol waste vented from the production rooms of the four power generating units via the two exhaust stacks. Data available support the inference that the power station exerts no harmful in- fluence on the surrounding environment, and that the level of radioactivity of the environment is com- mensurate with the natural background. Various devices and protection equipment used in service, in deactivation operations, in inspection and maintenance of radioactive equipment, aid in maintaining a level of personnel exposure doses below public-health regulation levels. Even though the probability of a serious accident associated with release of radioactivity from the primary loop is very small, the station personnel is carrying out intensive work on periodic checkups on the state of the metal in the equipment and piping of the reactor installation during the period when nuclear fuel in the reactor is replaced, and a practically complete volume of monitoring and inspection work is carried out within the space of four to five years. An especially large volume of work in investigating the metal in the pipings was carried out during the period of inspection of the first power generating unit. Consequently, a basic summary of experience in the operation of the four power generating units over the 10-year period that the Novovoronezh nuclear power station has been in service leads to the con- clusion that significant progress has been achieved in power station equipment and technology in the case of power stations using VVER type reactors, which are reliable sources of electric power and installations that are safe for the nuclear power station personnel and staff, for the surrounding population, and for the local environment. A further expansion of the Novovoronezh power station is being planned with the scheduled introduc- tion of a fifth power generating unit incorporating a VVER-1000 reactor, construction work on the reactor and power generating unit as a whole having begun back in 1973. The latest engineering solutions result- ing in lower costs and enhanced safety will be materialized in the designs for the fifth power generating unit. Plans call for building a shielded concrete enclosure for the primary loop, which is intended to com- pletely localize and trap radioactivity in the event of accidents involving leakage of coolant. The dimen- sions of the core are being increased by a factor of almost 1.5 while the pressure vessel size remains the same, and this is being achieved through modifications in the reactivity control system. The unit power rating of the turbogenerators is being increased to 500 MW. After the fifth power generating unit starts generating power at the outset of the next Five-Year Plan, the total power output of the NVAES will be increased by another 1000 MW. Engineering cost figures for the operation of the nuclear power station, which are even now comparable to the figures for the operation of fossil-fuel power generating stations in the central region of the nation, are undergoing impressive improvements at the same time. 9 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 EFFECT OF TEMPERATURE DISTRIBUTION ON THE SWELLING OF UO2 AND UO2 ? Pu02 CORES V. I. Kuztmin and I. G. Lebedev UDC 621.039.542.342 One of the processes influencing the efficiency of fuel elements, including those based on oxide fuels of the UO2 and UO2?Pu02 types, is the radiation-induced swelling of the fuel. Experimental data [1, 2] relating to the influence of individual parameters on volume changes taking place in these types of fuel as a result of irradiation often disagree both quantitatively and qualitatively. Calculations of volume changes in oxide fuels (especially those due to gaseous fission products) cannot as yet be carried out with adequate accuracy. ? The contribution of solid fission products to swelling was determined earlier [3, 4]. In the pre'sent investigation we determined the influence of temperature distribution in irradiated UO2 and UO2?Pu02 fuels on the total porosity, and considered methods of calculating the volume changes taking place in cyl- indrical oxide-fuel cores. METHOD We studied UO2 samples and mixed UO2?PuO2 fuel containing15 and20%Pu02. Sintered moldings were placed in 01011 61\115M3B steel cans and these were then sealed hermetically by welding. The samples were irradiated in an SM-2 reactor to various degrees of burn-up (0.4-17% of the heavy atoms) (Table 1). The can temperature was measured during irradiation with Chromel?Alumel thermo- couples, and the fuel temperature was determined by calculation. The maximum error in determining the temperature of the fuel in the center of the moldings was not greater than 200?C. The burn-up was deter- mined by y or mass spectrometry. The swelling of the fuel in all samples except those irradiated with a linear power of over 400 W/cm took place without any restraint on the part of the can. The gas pressure inside the samples at the end of irradiation was no greater than 30 kg/cm2. The samples were studied under the microscope. Using photographs of the microstructure and the method of secants [5], the total porosity was determined in several regions at different radii. The volu- metric proportion of pores with a diameter of over 0.8 p was determined in the optical microscope, and that of pores with diameters of 0.02-0.8 p in the electron microscope by the replica method [6]. The con- tribution of still finer pores with diameters of 15-32 A was calculated after studying the UO2 by trans- mission electron microscopy [71. RESULTS The results of the porosity measurements for different degrees of burn-up are presented in Fig. 1, which also shows the porosity of the non irradiated samples (for comparison). The porosity/burn-up rela- tionship and the absolute values of the porosity corresponded to the existence of three temperature zones, 1000-1500, 1500-1700, and 1700-2500?C, respectively. In zone 1 the porosity of the samples before irradiation equalled 5-9%; after irradiation to burn-up values of 1-5% it fell sharply. The fall varied in different cases. The maximum reduction in porosity occurred in samples irradiated to a burn-up of 1%, in which the grain size and the size of the original Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 11-15, January, 1975. Original article submitted December 24, 1973. 0 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 10 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 TABLE 1. Characteristics of the Samples TABLE 2. Values of the Coefficients CI and and Conditions of Irradiation C Composition of sam- ple 0 ,tz 41 is. 70., 0 .m Temperatu of fuel 0.) usz. gt,) :35 > o 0. E 4)0 on the sur- face in the cen- ter ? UO2 5 700 1700 0,4 350 UO2 5 1230 1600 1,0 275 UO2 5 1400 2200 1,3 345 1.102 6 920 1550 2,7 250 UO2 7 1230 2350 2,9 440 UO2 6 1120 1800 3,0 305 UO2 8 800 1450 4,2 255 UO2 6 1050 2250 4,8 510 UO2 2,5 890 1460 5,3 320 UO2 9 780 1860 5,6 300 1102 8 1000 2050 6,6 415 UO2 9 1100 2500 8,1 500 UO2 8 1100 2000 12,8 310 (0,2 Pu-0,8 U)02 2 1100 1800 14,6 245 (0,15 Pu-0,85 U)02 3 1150 1750 17,1 310 Coeffi- cient Temperature range, ?C 1000- 1500 1500?V700 1700- 250> dT dT dr 7". I dr > 500?C/mm ? ci cio 1,04 ?KP0 0,32 15 ? Po 0,32 ? Po 0,32 5 ? Po pores before irradiation were minimal. The porosity of the samples originally at a level of 5-7% remained unchanged after irradiation to a burn-up of 6-7%, but after a 14-17% burn-up it increased from 2-3 to 12-15%. The porosity of the irradiated samples depended linearly on burn-up within the range of measuring error (relative 15%). In zone 2 the porosity depended, not on the burn-up and original porosity, but only on the temperature gradient; this applied over the whole range of burn-ups (within the limits of measuring error). The absolute porosity in zone 2 for a gradient of under 400 deg/mm averaged 15%, and for a gradient of over 500 deg/mm it varied between 5 and 10%. In the zone of columnar grains (zone 3) the porosity was nonuniform. In the central part close to the cavity the porosity was usually higher, but the average value amounted to ?5%. DISCUSSION OF RESULTS The reduction in porosity observed in zone 1 after irradiation to a burn-up of ?1% might be asociated with two processes: sintering, and the filling of pores with solid fission products. In the samples irradiated to a burn-up of 1% the porosity diminished from 5 to 1%, while the volume of solid fission products for a burn-up of 1% was less than 0.7% of the volume of the fuel with the theo- retical density [4]. It follows that the reduction in porosity was in fact due to sintering. This con- clusion agrees with the results of [8]. The increase in porosity for greater degrees of burn-up as- sociated with the increasing dimensions and volumes of the pores due to gas accumulation. It is well known that the evolution of gas from this zone in UO2 tablets with a density of 10-10.7 g/cm3 equals 20-50% for a burn-up of '.4% [9], while the evolution of gas from zones 2 and 3 equals ..-'100% for a burn-up of over 1%. Growth of the pores takes place chiefly at the grain boundaries. In samples in which the zone size equalled 15-20 ?, considerable porosity also appeared inside the grains (at the subboundaries). The increment in the porosity of zone 1 observed for fuel with the theoretical density (introducing a correction for the nonuniform burn-up over the sample cross section) equalled 0.72% /1% burn-up within the range studied. In zones 2 and 3, saturation of the porosity changes occurred even at a burn-up of ?1%. The reason for this may be understood by analyzing the structure of the fuel. The pores in these zones lie chiefly at the grain boundaries and form a network of interconnected channels, which lie mainly on the lines connecting three neighboring grains. For this geometrical disposition of the pores, a considerable proportion of the surface of the grain boundaries is linked to the free surface, and the gas passing to a grain boundary emerges freely from the fuel (Fig. 2). The intragranular porosity in zones 2 and 3 also fails to increase on increasing the burn-up above 1%, since the rate of gas evolution at the grain boundaries is such that the krypton and xenon atoms so formed reach the grain boundaries in a time corresponding to a burn-up increment of 0.2%. This is con- firmed by calculating the velocity of the gas-filled pores in the field of the temperature gradient [10]. Saturation of porosity with increasing burn-up should also occur in zone 1 owing to the transition of a considerable proportion of the isolated gas pores to the open surface. However, saturation of the porosity in zone 1 was not in fact reached for a burn-up of 17%, owing to the low mobility of the gaseous fission fragments. For the same reason it would appear that saturation in zone 1 will set in gradually, from the region of highest temperature to the region of low temperature. The swelling of the fuel in the samples under consideration took place gradually as the gas pressure within the can increased, starting from 1-2 leg/cm2 at the onset of irradiation to 30 kg/cm2 at the end. 11 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 15 14 12 6 8 10 12 ?16 18 Burn -up, u/0 Fig. 1 Fig. 2 Fig. 1. Porosity as a function of burn-up in various temperature zones; 0) zone 1; G) zone 2, dT /dr 500 deg/mm);x) zone 3; A) original porosity. Fig. 2. Linking of pores at the grain boundaries. The external gas pressure on the fuel was insufficient to have any major effect on the porosity by virtue of gas-induced swelling. In samples irradiated with a linear power of over 400 W/cm the can was to some extent able to restrain the swelling of the fuel in the radial direction. However, porosity measurements revealed no marked influence of radial restraint. Zone Model for Calculating Volume Changes in Fuel-Element Cores The zonal character of the temperature dependence of the changes in porosity and also the quantita- tive data relating to changes in the volume of the fuel due to solid and gaseous fission products enable us to calculate the total volume effect in the cores of oxide fuel elements. If we consider part of the core with an external radius of R as having a length 1 so short that any change in the linear power and temper- ature along its length may be neglected, and assume that the burn-up is independent of radius, the in- crease in the volume of the annular layer may be expressed as follows: AV i =al (?+i) (CB (1) where Ci and Cio are coefficients characterizing the swelling in the zone limited by the radii ri and ri ?i; and B is the burn-up. The radius ri corresponding to the temperature Ti for a specified linear power q1, core surface temperature TR, and thermal conductivity A is determined from the equation T ( i 4n S ), (T) dT rl = R2 1 TR . qt The relative change in the volume of the selected part of the core is determined from the equation AV/V.= 4ril qi 2 (CB --00) (T) d7: i=1 Ti (2) (3) The number of zones depends on the temperature distribution. If the temperature in the center is no greater than 1700?C, the calculation is carried out with a two-zone model. For a higher temperature a three-zone model is needed. The coefficients C1 and Cio determine the terms in (3), respectively, dependent and independent of the burn-up. The value of the coefficients Ci equals the sum of the changes in volume of the i-th zone of 12 Declassified andApproved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 10 2 4 6 Porosity, lo Fig. 3 8 10 -2 -4 7 J 5 7 9 Burn-up, ?10 Fig. 4 11 13 Fig. 3. Increase in the volume of a uranium dioxide core as a function of the porosity of the moldings: and - ?- ? - ? -) Tsurf= 1000 and 1200?C; qi =350 and 550W/cm, respectively. Fig. 4. Increase in the volume of uranium dioxide cores as a function of burn-up (K = 0.5). Curve nomenclature as in Fig. 3. the core due to the solid and gaseous fission products on increasing the burn-up by 1%. The change in vol- ume due to the solid fission products is the same for all the zones and equals -0.4% [3] or according to refined data 0.32%. The change in volume due to the gaseous fission products is 0.72% for the first zone as already indicated and zero for the second and third zones, since the porosity is then independent of burn-up (Fig. 1). After summing the contributions of the solid and gaseous fission products, we obtained the coefficients C1, C2, and C3. The coefficient C1;0 equals the product KP0. The coefficient of radiation-induced sintering K deter- mines that part of the original porosity Po which vanishes as a result of sintering under irradiation. The values of the coefficients C2;0 and C3;0 equal the difference between the porosity corresponding to satura- tion and the original porosity. Table 2 gives the coefficients Ci and Cio used for the burn-up range 1-17%, an original porosity of 2-10%, and temperatures of 1000-2500?C. Substituting the corresponding values of Ci and Cio we obtain the following for the two zones: .2B ( 100-P0 41r [ 100 1 TC 1500 Ar ? 100?o' -0 3 (O. I2B?KPo) (T) dT (15 - P 0) X (T) dr] ; 1500 surf and for the three zones: (4) 1500 1700 av?100% = 0.32B ? . - ( 1??- ) 43 [(0 72B KP (T) dT?(7-P0) S (T) dr (5 - P0) X (T) dr]. (5) iuu Tsurf 1500 1700 Equations (3)-(5) may be used for a solid core if the external pressure is no greater than 30 kg/cm2. Figures 3 and 4 give the results of a calculation of the volume changes taking place in the fuel for various initial porosities, burn-ups of 5 and 10%, and linear powers of 350 and 550W/cm. In the calculation it was as- sumed that the sintering coefficient equalled 0.25 or 0.5 and the temperature on the fuel surface 1000 or 1200?C. As indicated by Eqs. (4) and (5) and Figs. 3 and 4, an initial porosity is useful for reducing the volume changes in all the temperature ranges. With increasing linear power the swelling is reduced, since the volumetric proportion of zone 1 in the core diminishes, and that of the fuel in the plastic zone 3 (less subject to gas swelling) increases. This may have important consequences, since the deformation of the can is mainly due to the "rigid" peripheral layer of fuel. 13 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Thus we have analyzed the distribution of porosity in the cores of UO2 and UO2-Pu02 fuel elements irradiated in the burn-up range 0.4-17% at linear powers of 250-510W/cm by quantitative metallography. We have given a qualitative description of the mechanisms underlying gas-induced swelling and gas evolu- tion in the oxide fuel. We have shown that gas swelling reaches saturation in the core zone for a burn-up of -1% and temperatures of over 1500?C. In the core zone the porosity increases with burn-up at a tem- perature of 1.4 MeV in iron?water mixtures of varying composition; the values were obtained by an analysis of the results of the calculations. The table makes it clear that an insignificant reduction in relaxation length is observed as the source distance increases for iron?water mixtures containing more than 50 vol. % of iron. A (; : similar effect was observed in an analysis of the penetration of fast neutrons from monoenergetic sources in heavy media [7]. LITERATURE CITED 1. D. L. Broder et al., At. Energ., 27, No. 3, 217 (1969). 2. L. I. Abagyan et al., Group Constants for Reactor Calculations [in Russian], Atomizdat, Moscow (1964). 3. M. N. Nikolaev and N. 0. Bazazyants, Anisotropy in Elastic Scattering of Neutrons [in Russian], Atomizdat, Moscow (1972). 4. B. R. Bergeltson et al., Multigroup Methods for Neutron Shielding Calculations [in Russian], Atom- izdat, Moscow (1970). 5. A. P. Veselkin et al., Atlas of Fast-Neutron Spectra [in Russian], Atomizdat, Moscow (1970). 6. Radiation Shielding Handbook for Engineers [in Russian], Vol. 1, Atomizdat, Moscow (1972), p. 287. 7. T. A. Germogenova et al., Fast-Neutron Transport in Plane Shields [in Russian], Atomizdat, Mos- cow (1971). 46 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 DOSE DISTRIBUTIONS IN PHANTOMS OUTSIDE 1-1000-GeV ACCELERATORS N. V. Mokhov, E. L. Potemkin, UDC 621.039-78 and V. V. Frolov We present here calculated results obtained from the FORTRAN program SHIPHA for the depth dose En phantoms produced by ionizing radiation produced in iron shielding of various thicknesses by primary protons with energies E0 =1-1000 GeV and mit flux density. In the SHIPHA program, calculation of the spectral and angular distributions of protons, neutrons, r?-mesons, K?-mesons, muons, and y -rays outside the shield is performed in the subprogram HAMLET [1, 2] over the energy range 10'2-1012 eV. Calculation of the dose distribution in a slab phantom 30-cm thick outside the shield is performed in the subprogram FANTOM [3]. The depth distribution for absorbed dose in the phantom is plotted in Fig. 1 for protons of energies 1, 10, 100, and 1000 GeV incident on an iron shield having a thickness H =1500 g/cm2. The distribution is exponential in nature because the dose is -90% determined by neutrons with E 5 10 MeV. Calculations show that the addition of a concrete layer -110 g/cm2 thick to the iron shield reduces the dose by roughly a factor of five and leads to comparable contributions to the dose from low-energy neutrons and high- energy hadrons. The energy dependence of the dose equivalent and the absorbed dose in a phantom outside an iron shield is shown in Fig. 2. There is a ',critical thickness,' of the shield at each energy such that the dose in the phantom for shield thicknesses less than the critical thickness is greater than without a shield. 10') 2 10 70-5 10 2 0) 10 1:1 2.2 ? 10-8Cr' a) 2 CI hie ?-cY ?c) !3--' du ill10-9 7,, I5 az- al 7 101 13? 10 ' 102 103 ler 0 10 20 ,cm Eo, GeV 0 1000 2000 3000 H, g/cm2 Fig. 1 Fig. 2 Fig. 3 70-io Fig. 1. Depth distribution of absorbed dose in a phantom outside an iron shield for various primary proton energies. Fig. 2. Dependence of dose equivalent (1) and absorbed dose (2) at a phantom depth x = 5 cm on the energy of protons incident on a shield of thickness H =1500 g/cm2; 3, 4) corresponding val- ues without shielding. Fig. 3. Dependence of dose equivalent (1) and absorbed dose (2) at a phantom depth x =12 cm on thickness of an iron shield (E0 = 50 GeV). Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 42-43, January, 1975. Original letter submitted April 15, 1974. ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 47 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 ? Dependence of dose equivalent and absorbed dose on the thickness of a shield irradiated by protons with an energy E0 = 50 GeV is shown in Fig, 3. Outside a shield of thickness ,.,3500 g/cm2, the dose is determined entirely by the muon component and the absorbed dose and dose equivalent are the same. The program SHIPHA makes it possible to calculate dose distribution in phantoms of arbitrary shape outside heterogeneous shields of thicknesses up to 5000 g/cm2. The program calculates the component contribution to absorbed dose and dose equivalent. The primary energies of broad, monodirectional beams of hadrons are E0 = 0.05-1500 GeV. The reliability of the resultant data was established by comparison of the calculated results from the HAMLET and FANTOM programs with experimental data in the energy range 0.1-100 GeV. The disagreement did not exceed 10% for dose calculations in phantoms [3, 4] and 30-50% for calculation of the intranuclear cascade in the shield [1, 2]. The computing time required to obtain results with an accuracy of 5-10% is ?1-1.5 h on the BESM-6. The program is useful for the estima- tion of the radiation environment to be encountered by space vehicles and that around existing and planned accelerators. LITERATURE CITED 1. L. R. Kimelt and N. V. Mokhov, Izv. VUZ, Fiz., No. 10, 18 (1974). 2. G. I. Britvich et al., IHEP Preprint 74-86 (1974). 3. V. T. Golovachik et al., IHEP Preprint 73-29 (1973). 4. V. T. Golovachik et al., IHEP Preprint 74-58 (1974). Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 MEASUREMENT OF of(2 39Pu)/of(23 5 U) AND (23 3U)/af(23 5U) FISSION RATIOS AT 2 keV V. G. Dukhsherstnov, V. L. Petrov, UDC 539.1.083 and V. M. Furmanov Evaluations of the effect of uncertainties in nuclear data on the design parameters and economics of fast breeder reactors [1, 2] indicate the need for refinement of the energy dependence of the effective cross sections for basic reactor materials. This refers primarily to the fission and radiative capture _ _ cross sections in U and Pu isotopes, for which the measurements still fail to show sufficiently good agree- ment. Useful information for the formulation of a recommended library of evaluated nuclear data can be obtained from measurements of the fission cross sections in U and Pu isotopes relative to the fission cross section of 235U. In the neutron energy range 1-5 keV, however, there is an extremely limited set of experimental data from "direct" measurements of the of(239Pu)/01(235U) [31 and o-f(233U)/crf(235U) [3, 4] ratios or from simultaneous measurements of of(23913u) and af(235U) [5, 61. Furthermore, the differences in the af(239Pu)/o-f(235U) ratios in [3, 5, 6] are significantly greater than the errors cited by the authors. This paper gives the results of "direct" measurements of the quantities o1(239Pu)/af(235U) and 7f(233U) /uf(23 5U) in the scandium neutron beam (2 keV) of the reactor at the Obninsk nuclear power station. METHOD Measurements of fission cross-section ratios were carried out in the "signal" spectrum of the scandium beam of the reactor at the Obninsk nuclear power station [7] by means of double fission cham- bers. Each chamber (239Pu/235U and 233U/235U) had five aluminum-foil electrodes ?0.1 mm thick on two of which a layer of fissile material was deposited on both sides in the form of a spot 14 x 9 mm in size. The total amount of fissile material in a single chamber was ?3 mg:1 mg of 239PU dioxide (-99.8%) or of uranous?uranic oxides of 233U (-99.9%) and 2 mg of uranous?uranic oxides of 235U (-90%). The elec- trodes were mounted on plastic insulators with a spacing of 1.5 mm inside aluminum housings having a wall thickness of 1 mm and filled with argon to a pressure of ?1.5 atm. The chambers were used in the current-pulse mode [8]. Calibration measurements with the double fission chambers were made in the neutron beam from a crystal monochromator [9] yielding energies of 0.051-0.056 eV. The admixture of neutrons with energies 0.193-0.235 eV in the spectrum of the diffraction beam was estimated by the authors [9] to be 10% of the flux of neutrons in the main group with an average energy of 0.053 eV. The results TABLE 1. Basic Experimental Characteristics Parameter Chamber 239pu/235u Chamber 233U/235U trionochromatori beam scandium beam monochromator beam I scandium beam Signal/background ratio Signal counting rate, cts/sec Ratio of chamber counts Measured cross section ratio in "signal" spectrum of scandium beam Cross section tatio for energy range 1.5-2:3 keV (2-keV peak) ? 33/48 ? 38/17 2,245+0,011 0,578+0,014 0,562+0,015 0,7/1,9 0,6/0,7 0,791+0,012 ? 60/53 ? 30/13 2,355+0,028 1,41+0,04 1,41+0,04 ?2,3/1,5 ?1,7/0,5 3,460+0,052 Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 43-44, January, 1975. Original letter submitted June 7, 1974, 0 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 49 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Fig. 1. Data for of(239Pu) /af(23 5U) range 1-3.5 keV. ?) [17]; - ? - 0) present work. of(233U) /0-f(235 U) and in the neutron energy 4) [4]; Or) [3]; C)) [51; ? -) [18]; - - -1 [16]; in the neutron beam of the monochromator were normalized to values of the ratios 0-f(239Pu)/af(235U) and af(233U)/o-f(235U) which were 1.651 0.03 and 0.96 ? 0.02, respectively, and which were calculated from evaluated data [10, 11] and from experiment [12-141. RESULTS Table 1 gives the main results of the experiment in the neutron beam from the crystal monochro- mator and of the experiment in the scandium beam for a reactor thermal power of -11 MW at the Obninsk nuclear power station. To obtain the fission cross-section ratios for the energy range 1.5-2.3 keV, a correction was introduced for the nonmonoenergetic nature of the spectrum of the "signal" scandium neu- tron beam in accordance with data of the BNAB system of constants [151. The mean-square error given in Table 1 includes the statistical error of the measurements and the uncertainties in the calculated normal- izing constants and corrections. Figure 1 shows data for af(233U)/o-f(235U) and o-f(239Pu)/af(23U) in the neutron energy range 1-3.5 key. It is clear that the present data for o-f(233U)/7f(235U) agrees within the limits of error with the results of spectrometric "direct" measurements with double fission chambers for the slowing-down time in lead [3] and from a high-altitude nuclear explosion [4]. The data obtained for 01(2391:v)/Q1(235U) agrees satis- factorily with experimental results [51 where af(239Pu) and af(235U) were measured "simultaneously" in a lead cube and also with previous evaluations [16, 171. The values of the ratio af(239Pu)/o-f(235U) calculated from the data in [51 and [61 for the spectrum of the 2-keV peak of the scandium beam are 0.556 and 0.713. The first result is in good agreement with the data in Table 1. In conclusion, the authors thank V. S. Golovkin for providing the opportunity to carry out the calibra- tion measurements in the beam of the crystal monochromator and Yu. A. Kazanskil and S. P. Belov for consideration of this work. LITERATURE CITED 1. P. Greebler, B. Hutchins, and C. Cowan, in; Proceedings of the IAEA Symposium "Nuclear Data for Reactors - 1970' Vol. I, June 15-19, Helsinki (1970), p. 17. 2. S. M. Zaritskii, M. N. Nikolaev, and M. F. Troyanov, Neutron Physics [in Russian], Vol. 1, Naukova Dumka, Kiev (1972), p? 3. 3. W. Lehto, Nucl. Sci. and Engng., 39, 361 (1970). 4, R. Albert, Phys. Rev., 142, 718 (1966). 5. A. A. Bergman et al., Nuclear Constants [in Russian], No. 7, Izd. TsYaD, Obninsk (1971), p. 37. 6. Yu. V. Ryabov et al., At. Energ., 24, No. 4, 351 (1968). 7. E. N. Kuzin et al., At. Energ., 35, No. 6, 391 (1973). 8. Kononov et al., Prib, i Teich. Eksp., No. 6, 51 (1969). 9. V. S. Golovkin, V. N. Bykov, and V. A. Levdik, Zh. Eksp.Teor. Fiz., 48, No. 4, 1083 (1965). 10. Parker's Evaluated Data from the 1968 UK Nuclear Data Library, DFN-65, DFN-66. 11. B. Leonard et al., Evaluated Nuclear Data File of National Neutron Cross-Section Center, 239Pu Data, Mat.-1104, April (1970). 12. R. Gwin et al., Nucl. Sol. and Engng., 45, 25 (1971). 50 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 13. L. Weston et al., Nucl. Sci. and Engng., 42, 143 (1970). 14. R. Freemantle, Rep. AEEW-M-502 (1965). 15. L. P. Abagyan et al., Group Constants for Reactor Calculations [in Russian], Atornizdat, Moscow (1964). 16. W. Davey, Nucl. Sei. and Engng., 26, 149 (1966). 17. W. Hart, Rep. AHSB(S)R-169 (1969). 18. T. Beyer, Atomic Energy Rev., 10, No. 4, 529 (1972). 51 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 FAST NEUTRON SPECTROMETRY OF (a, n) REACTIONS USING A DEUTERA TED SCINTILLA TOR E. M. Burymov, S. P. Korsunova, UDC 539.125.5.164.07 and N. N. Spendiarov A deuterated scintillator (octadeuteronaphthalene) was used in the work of Burymov et al. [1] for neutron spectrometry in an investigation of inelastic scattering. Neutron spectra from (a, n) reactions in the nuclei 9Be, 19B, and 11B were measured by the same method in the present work. The experiment was performed at the 120-cm cyclotron of the Research Institute for Nuclear Physics, Moscow State University with 23- and 25-MeV a-particles. Target thicknesses were 1-2 mg/cm2. A crys- tal of octadeuteronaphthalene 30 mm in diameter and 20 mm high at 23 cm from a target was used in con- junction with an FEU-29 photomultiplier for neutron spectrometry. The spectrometer was calibrated with 14.1-MeV neutrons. 300 200 100 0 100 0 15 70 Ed, MeV 15 20 Ed, MeV 100 50 80 60 40 20 0 15 20 Ed, MeV 15 20 Ed, MeV E,-23Me 95-40? 15 20 Ed, MeV 60 40 20 0 Fig. 1. Pulse-height spectra of scintillator recoil deuterons from elastic scattering of neutrons produced in the reactions: a) 9Be(a, n)12C; b)19B(a, n)13N; c) itwa 014? DI [Ed) energy of recoil deuterons; N) number of counts per analyzer channel; arrows indicate the position of the peak in the recoil deuteron spectrum corresponding to the energy of emitted neutrons when the final nucleus remains in the ground state; En (9/8)Ed]. Translated from Atomnaya Energlya, Vol. 38, No. 1, p. 45, January, 1975. Original letter sub- mitted March 15, 1974. 0 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 52 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Neutron spectra are shown in Fig. 1 for several angles of emission. The time of measurement for each spectrum was ?10 min at a beam current of ?0.1 A. Since a single-crystal arrangement was used, great difficulties arose because of the y -background. It was particularly great for signal pulses smaller than pulses corresponding to neutrons with energies of 18-20 MeV (this energy decreases somewhat as the angle increases). In those cases where the neutron energy exceeds this value, peaks are observed in the experimental spectra corresponding to the ground state in the final nucleus (see Fig. 1) and to the first excited state in particular cases. This is observed in all the reactions studied at angles less than 90?. In the 12C(oz, n)150 reaction, the maximum neutron energy is 13.5 MeV for Ea = 25 MeV andtherefore peaks cannot be observed. Thus we have demonstrated the possibility of using a single-crystal deuterated neutron spectrometer for studying (a, n) reactions in cases where the neutron energy is sufficiently high (greater than 18-20 MeV). LITERATURE CITED 1. B. A. Benetskii, E. M. Burymov, and I. M. Frank, Yad. Fiz., 8, No. 5, 920 (1968). 53 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 INITIAL STATIC FOCUSING IN SMALL LINEAR TRAVELING-WAVE ACCELERATORS A. D. Vlasov UDC 621.384,64.01 In a traveling-wave linear proton accelerator, an effect occurs which is similar to static electric focusing in cyclotrons [1] and in linear accelerators with drift tubes [2, 3]. A momentum directed towards the axis acts on a particle upon entrance into the accelerating wave and a momentum oppositely directed upon leaving the wave. In a low-energy accelerator for acceleration of protons from 50-100 keV to several MeV, the focusing action of the initial momentum can be sufficient to allow one to get along without special focusing devices. The longitudinal electric component of the accelerating wave has the form E, cos ( --v? ?o)t = Em cos cp, dz where z, go, and v are the longitudinal coordinate, phase, and velocity of a particle; t is time; co = 2A-c/X (here, X is wavelength and c is the velocity of light). We assume the wave amplitude Em and the equilibrium phase (pp are constant along the accelerator, and we confine our considerations to the equilibrium particle. The longitudinal motion of this particle occurs at a constant acceleration eEm cos (pp/mo and is described by the equations (1) eEm COS (pp W052 Z? t0 ? 2m0 2eEm COS (Fp Here e, mo, and Wo are the change, mass, andrest energy of the particle; 0 = vp/c; vp is the equilibrium velocity. If, for example, Em. = 3 Mv/m, cOp = 30? and the protons are accelerated from 100 keV (f3i = 0.0146), zi = 38.5 mm. For a final proton energy of 750 keV (pf = 0.0400) and 5 MeV (Of = 0.1028), the accelerator length, Zf?Zi, is 0.25 and 1.86 m, respectively. If X = 2 m, the duration of particle accelera- tion, c(tf?ti) /X will be 4.6 and 16 cycles of the hf field. For X = 24 m, we obtain only 0.4 and 1.3 cycles, respectively. The number of phase oscillations is given by 2Wo sin (pp n.43.? 1/Ff? 1/N) ? aeEmk cos2 (pp For the parameters given above and X = 2 m, it becomes 0.5 and 1.62, and for X = 24 m we obtain the values 0.2 and 0.5. The transverse momentum acting upon a particle when it enters or leaves the field of the wave (Eq. (1)) is calculated by integration of the equation of transverse motion d2x dzx oP2 ? m? dt2 dZ2 ex aE. 2 az ? For the equilibrium particle, these momenta are dx ex, , eET,icos cp x / ?1L ? 21'il di- 2ft0f2 Translated from Atomnaya. Energiya, Vol. 38, No. 1, pp. 46-47, January, 1975. Original letter submitted June 6, 1974. 0 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 54 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 and their effect is given by the matrices where ? 1 . 0 \ f _ i,f The transverse motion of the equilibrium particle in the field (1) is described by ci2x , sneEm sin cpp x nEm sin (pp x 60 11 .1 x Eix= p , E0x= R2 (2) are the transverse components of the accelerating wave and the intrinsic Coulomb field of the accelerated beam (I is beam current; R is beam radius) is 8 60 = 0 Elx ztEmR2 sin (pp We obtainE '5- 1.1 for Em = 3 MV/m, cpp = 300, X = 24 m, and I/R2 5- 33 mA/cm2. The expression for E 2x corresponds to a cylindrical beam. The radius of the beam varies and the beam breaks up into bunches in proportion to acceleration. Both these factors lead to a variation in E. For simplicity, we assume below E = Emax = const. Expressing 8 through t, we bring Eq. (2) into the form d2x px dt2 4t p=2?0.)tg cpP. The solution of this equation and its derivative are given by MI I (T) K (T) , , dx dt x = tit dz = 4z where T = )rpl. Setting T = Ti = 1./71 in these equations, we determine the constants of integration A and B through xo and x = (dx/dz)o, and obtain a matrix equation connecting the instantaneous values x and x/ with the initial values, Here, ( 27,)= (bb 21 b11b 2122) (r4o ) b11=---T [K0 (1 ? 1) 11(T)+ 10 (t) 1C (T); 4z .x b12 ? ? [If 1 (1111 (t) ?It (ti) IC 1 (TA; _ 1 b21? ? [K0 (xi) 1.0 (x) ? 10 (xi) Ko (T)1; P. -? by, ? ? [K1 (TO /0 (T) it (T) Ko (T)1. The matrix determinant bilb22?bi2b2i = i//3 differs from unity and decreases like 13-1. The variation of x and xl over the length of the accelerator including the initial and final momenta is given by the matrix product x\ (I 0\ (b11 b12) (I 0 (all av2,1 \ / 621 lin ,/ki.1/\xJ a A. 21 an/ xi ? i? / Multiplying the matrices, we find ? ait=xf [Ko (Ti) Ki (1i) /2 (ti) ? [10 (x0+ (xl) 1C1 (Tf) ; T T a12 (K1 (TO /I (Tf) ? it (TO K2 (TM; Ti 55 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 a21=1 ito (Ti) ?ripi [ Ki (Ti) ] L + if (rf) 1 [10 (To 4_ ii(Ti) 1 r,?0(tf) K (stf) ]) ; Ti 't a22=-Ti-L-4 {KJ (Tii)L 11-/i(g)[K, (Tf) K1 (1f) } ? pf Tif Tf The matrix elements a ij depend on the four quantities Th pi, pf, and zi, with the last depending mainly on Em and (3 i since cos (pp 1. Thus for given Em, (31, and 13f the matrix elements a ij are deter- mined by the values of Ti or, alternatively, by the quantity EM? cos2 (Pp 4nW9 Ti ? sm (pp The optimal choice of Ti depends on the parameters of the injected beam and on the requirements imposed on the beam at the accelerator exit. In particular, one can select Ti from the condition Ko(ri)? Kt (xj)? 0. ?r ? Then, neglecting terms containing Ko(Tf) and KI(Tf) in the expressions all= [10 (TO+ 11 (Ti) TfiCi (TO; T ? 1 21 , ? a12=4? A 1 (T1) 'till (TO; Ti EIO Ki (Tf) 1 , a21= 4z10 f (Ti) Ti [K? (Tf) T for a12 and a 22, we obtain (3) ? a22= 113fi (Ti) (Tf)J,-- 111!tf) . f - The root of Eq. (4) is T =1.33, to which Ti = 6630 MV corresponds. A wavelength A = 23.6 m is required according to Eq. (3) when Ey/ = 3 MV/m, e = 1.1, cpp = 300, and the initial proton energy is 100 keV. If the protons are accelerated to 750 keV and 5 MeV, we, respectively, obtain Tf = 2.2 and 3.5 and au= 0.50; 0.16, a12=0.174; 0.925 m, 021= ?0.36; ?0,044 m-1, a22 = 0.61; 0.64. These elements a ij are not too large and therefore the transverse deflections and trajectory slopes of the particles at the accelerator exit will .have acceptable values. If A = 2 m, we obtain (pp = 3?14' for the same EM, E, and 13 i. The values of Ti,f and a ij obtained in this case are not much different from those obtained above. Thus, although the choice T = 1.33 may differ from the optimal choice, the initial static focusing is still sufficiently effective. Having selected the quantity TE, it is necessary to choose an optimal wavelength and equilibrium phase, which are related through Eq. (3). To do this, it is necessary to know the spreads in exit energy, deflection and trajectory slope of nonequilibrium particles corresponding to various A. and (pp. The motion of nonequilibrium particles can only be calculated by numerical methods on a computer. LITERATURE CITED 1. A. A. Kolomenskii and A. N. Lebedev, Theory of Cyclic Accelerators [in Russian], Fizmatgiz, Moscow (1962). 2. A. D. Vlasov, Theory of Linear Accelerators [in Russian], Atomizdat, Moscow (1965). 3. I. M. Ka.pchinskii, Particle Dynamics in Linear Resonance Accelerators [in Russian], Atomizdat, Moscow (1966). 56 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 DEPENDENCE OF THE FISSION-FRAGMENT SPUTTERING RATIO FOR THIN LAYERS OF A SUBSTANCE ON THE MEAN ENERGY OF THE FRAGMENTS B. M. Aleksandrov, N. V. Babadzhanyants, I. A. Baranov, A. S. Krivokhatskii, L. M. Krizhanskii, and V. V. Obnorskii UDC 546.799 In [1], it was shown qualitatively that the sputtering ratio K for thin layers of 241Am oxide is larger, the higher the mean energy of the fission fragments. We assume that the difference, obtained in [2-5], in the measurements on thin films of UO2 (K 104 atoms/fragment), on thick, coarse-grained baked disks of UO2 (K 9 atoms/fragment) and on metallic disks of plutonium and uranium (K io atoms /fragment), respectively, can be partly associated with the difference in the energy spectra of the fission fragments, since the latter originated inside layers of different thickness and crossed the sputtered surface at dif- ferent angles. The problem in this paper is the quantitative determination of the dependence of the sput- tering ratio for thin layers of a substance on the mean energy of the fragments. Studies of a dependence of this kind allow one to ascertain those interactions of the fission fragments with the atoms of the substance (elastic or inelastic) which cause the sputtering, to verify the assumption expressed concerning the source of the spread in the experimental data on K in [2-51, and also have a definite practical value. In this paper, we investigated the sputtering of fine-grained layers, prepared from 238PU by elec- trolysis of an aqueous solution and representing hydrated plutonium oxide, desiccated in air at room tem- perature. A thin layer of 2 52C f served as a source of the fragments. The plutonium layer undergoing sputtering and the californium layer were mounted parallel to each other, 7 mm apart, in a holder and placed in a special vacuum chamber. A rotating disk was placed between the layers. Ten thin nickel films, transparent to the fission fragments, and two thick foils, nontransparent to the fragments, were placed in openings along the rim of the disk. The fission fragments from the californium layer passed through the two protective nickel films, then the nickel-film collector in the disk, after which they fell almost perpen- dicularly on the plutonium layer, sputtering it. The sputtered atoms of plutonium were collected by the nickel collector-film located 2 mm from the plutonium layer. After 2 h of exposure, the disk was reversed (without any change in the high vacuum) and another collector with a different thickness of nickel film was placed between the layers of plutonium and californium, whereas the first collector-film was located above a surface-barrier, silicon a-counter. The a-spectrum of the collector was measured with the aid of an AI-256 multichannel amplitude analyzer with a precision-amplitude generator. The number of plutonium atoms collected by the collector was determined from the a-particle counting rate and the presence or absence of contamination from the 252Cf was monitored in the spectrum. At the same time, a correction for the self-sputtering of the plutonium layer due to a-decay was taken into account. After the first series of measurements (sputtering in all of the 12 collectors and production of a-spectra with each one), two more series of measurements were conducted without impairment of the high vacuum, after which the layer being sputtered was replaced. In all, four plutonium layers with different sputtering ratios (500, 185, 130, and 70 atoms/fragment) for a maximum mean energy of the fragments ?87 MeV were subjected to sputtering. With a decrease in the mean energy to 23-27 MeV, the ratios for these layers were reduced to 100, 33, 40, and 20 atoms/fragment, respectively. The dependence of the sputtering ratio on the mean energy of the fragments for a layer with a maximum sputtering ratio of 500 atoms/fragment is shown in Fig. 1. The errors indicated represent the variances obtained as a result of three series of measurements. The curves for other plutonium layers have the same character; however, one should mention a certain Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 47-49, January, 1975. Original letter submitted July 1, 1974. ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 57 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 200 600 1000 1400 1800 1, g/cm2 Fig. 1 Fig. 1. Dependence of the sputtering ratio of a thin layer of hydrated plutonium oxide on the mean energy of the fission fragments for 232Cf (1 is the thickness of the nickel films). Fig. 2. Change in specific ionization dn/dx and specific energy losses dE /clx along a track x of 244Cm fission fragments [6]: 1, 2) for light and heavy fragments, respectively; 3) averaged values of curves 1 and 2. 2200 2600 3000 12 16 20 24 X,mm Fig. 2 100 75 50 25 0 tendency towards a reduction in the slope of the curves for plutonium layers with a lower sputtering ratio. The film thicknesses range from 300-2800 pg/cm2, and the energy spectra of the fragments after passing through these films were determined with a semiconductor spectrometer before the start of the experiment. Three energy spectra for the fission fragments, which characterize the energy distribution of the frag- ments after passage through 300, 1600, and 2800 ptg/cm2 nickel films, are given in Fig. 1. With a de- crease in the mean energy of the fragments from ?87 to ?25 MeV, the sputtering ratio is reduced by a factor of 3.5-6 as a function of the quality of the layer undergoing sputtering. Thus, for fine-grained layers of a nonconducting substance, the sputtering ratio depends substantially on the energy of the frag- ments, if this energy >20 MeV. One can assume as completely valid that the difference in orders of mag- nitude in the sputtering ratios of thin, fine-grained films [2] and thick, metallic disks [4, 51 could be as- sociated, completely or to a significant degree, with the difference in the mean energy of the fission frag- ments. On the other hand, the rate of change of the sputtering ratio with a change in the energy attained En this experiment can probably not explain the large difference in the sputtering ratios of the fine-grained layers and films [1, 2], and the coarse-grained disks [3]. This apparently says something about the dif- ferent mechanisms for the sputtering of coarse-grained and fine-grained samples. From the data obtained, it also follows that the sputtering of coarse-grained, nonconducting layers by fission fragments with ener- gies from ?20 up to ?100 MeV occurs mainly because of inelastic interactions of the fission fragments with the atoms of the substance. This is seen from the character of the curve in Fig. 1, which agrees qualitatively with the experimentally obtained curve for dE /clx as a function of x (Fig, 2, [6]), By investi- gating the question of the possible effect of the size of the grains on the value of the sputtering ratio, one can attempt to utilize the same reasons which were applied in [7, 8] for explaining the formation of tracks from the fission fragments in different substances. Thus, one can assume that reflection of phonon waves, low-energy electrons, and excitons, which arise during the passage of a fragment through a grain, occurs at the boundary of the grain. These phenomena must inhibit the dissipation of energy, evolved within the grain, beyond the limits of its boundary. At the same time, the amount of energy evolved in the grain by the fission fragments and the degree of dissipation of this energy beyond the extent of the grain will depend on its size. In fact, tracks from the displaced material were observed only in fine-grained films; the maximum sputtering ratio (104 atoms/fragment) was measured for fine-grained layers. Hardly noticeable tracks of a discontinuous character were observed in coarse-grained, insulating materials; the sputtering ratio for such materials proved to be a minimum (5-10 atoms/fragment). However, there is also a dis- crepancy. Thus, no tracks are observed in metals, although the sputtering ratio for metals proved to be significant (103 atoms/fragment). It is of interest to investigate the dependence of the sputtering ratio on the mean energy of the fission fragments in an experiment similar to the one described here for metals and a coarse-grained, nonconducting material. 58 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 LITERATURE CITED 1. B. M. Aleksandrov, A. I. Baranov, A. S. Krivokhatskii, and G. A. Tutin, At. Energ., 33, No. 4, 821 (1972). 2. M. Rogers, J. Nucl. Mater., 15, No. 1, 65; 16, No. 3, 298 (1965). 3. G. Nilsson, J. Nucl. Mater., 20, No. 2, 215 (1966). 4. F. S. Lapteva and B. V. Ershler, At. Energ., No. 4, 63 (1956). 5. M. Rogers and J. Adam, J. Nucl. Mater., 6, No. 2, 182 (1962). 6. F. Nasyrov, At. Energ., 16, No. 5, 449 (19-64). 7. M. Goland, J. Appl. Phys., 35, No. 7, 2188 (1964). 8. K. Jzui, J. Phys. Soc. Japan, 20, No. 6, 915 (1965). 59 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 SILVER CHLORIDE TRACK DETECTORS N. P. Kocherov, N. R. Novikova, UDC 539,1,073:546,57,131 and N. A. Perfilov Since 1960, work has been done in France and FRG on the recording of charged-particle tracks in flat single crystals of AgCl. The principle of operation of such detectors is based on the process of photo- lysis in silver halide crystals. When a charged particle passes through the crystal, a chain of defects is formed along its trajectory. If the crystals exposed to particles are thereafter subjected to photolysis under the action of actinic light (X 410 nm), metallic silver will be produced at the defects caused by the particles, and the resulting tracks will be visible under the microscope. The tracks found in crystals are very similar in appearance to tracks in emulsions. In 1972, Schopper [11 established that the latent image of the particles in AgC1 crystals is stable when the crystals are illuminated with yellow light at the instant of exposure, whereas when there is no illumination at the instant of particle action, the image regresses rapidly. This makes it possible to turn the sensitivity on and off whenever necessary for the experimenter. In the present paper we report on our experience in the preparation of such detectors and on their properties. The original AgC1 salt was recrystallized by dissolving in ammonia and subsequently precipitating it by means of HC1. The resulting reagent was spectroscopically pure with respect to metals of valence 2 or higher.* The single crystals were grown by letting the solution flow between quartz and glass plates [21 and had dimensions of 15 x 10 x 0.15 mm. In principle the area of the crystals can easily be increased by a factor of 2-2.5. Crystals grown from AgC1 with no additives do not record even fission fragments. Crystals alloyed with 0.1% CdC12 by weight record the a-particles from the decay of 252Cf but are insen- sitive to protons. Crystals alloyed with 0.5% CdC12 record protons up to an energy of 4 MeV.t The rate of regression of the latent image when the AgC1 is exposed to particles without being illuminated depends on the specific energy losses of the recorded particles: the images persist for minutes in the case of protons, for hours in the case of a-particles, and for days in the case of 252Cf fission fragments. If the crystal is illuminated with yellow light at the same time as it is exposed to particles, the latent image is stable for several months [1]. Fig. 1. Photomicrograph of tracks in an AgC1 crystal irradiated with 660-MeV pro- tons. AgC1 detectors are transparent crystals: they can be stored for long periods and used under conditions of illumination with long waves measuring 440 nm or more. An image appears when the crystal is illuminated with light having a wavelength of X 410 nm (for example, 5-8 min of exposure to direct sunlight filtered through ZhS-10 and P8-15 filters). Fixing the image is not necessary. In external form (see Fig. 1) the particle *The recrystallization of the reagent was carried out by P. I. Chaikin and 0. V. Kesarev at the Scientific- Research Institute of the Jewel Industry. tDetectors capable of recording protons with energies up to 14 MeV are being produced today. Translated from Atonanaya Energiya, Vol. 38, No. 1, pp. 49-50, January, 1975. Original letter submitted July 1, 1974. 0 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 60 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 tracks in the crystals exhibit almost no differences from tracks obtained with nuclear photographic emul- sions (31 Thus, the use of silver chloride detectors in the case of prolonged exposure (of the order of weeks or longer) makes it possible to turn the detector sensitivity on and off whenever necessary. The particles recorded in the crystal will then be those which passed daring the time of exposure to yellow light plus the time of regression. In the case of short exposures (seconds) without illumination, the crystals can be developed after various intervals of time following the exposure, which makes it possible to obtain a series of detectors with different recording thresholds, since the regression time of the latent image depends on the specific energy losses of the recorded particles. It is possible to conduct biological experiments with objects mounted on the surface of the detector: development using light does not destroy the objects and makes it possible to observe them together with the tracks of the particles impinging on them. ? Silver chloride detectors make it possible to study nuclear reactions on silver and chlorine without any background from reactions involving light nuclei, which interfere seriously with the use of nuclear emulsions; they can also serve as fast-neutron dosimeters, using the (n, p) and (n, a) reactions on silver and chlorine [41. Since these detectors are simple to produce and have convenient properties, it may be supposed that they will come into wide use in the near future. LITERATURE CITED 1. B. Schopper et al., in; Proceedings of the Eighth Conference on Nuclear Photography and SSTD, Vol. 1, Institute of Atomic Physics, Bucharest (1972), p. 350. 2. A. M. Levitskaya and A. M. Korolev, Zh. Teich. Fiz, 7, 760 (1973). 3. N. A. Perfilov, N. R. Novikova, and E. I. Prokoffeva, At. Energ., 4, No. 1, 45 (1958). 4. G. Henig et al., in: Proceedings of the Eighth Conference on Nuclear Photographyand SSTD, Vol. 1, Institute of Atomic Physics, Bucharest (1972), p.384. 61 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 CHANGE IN THE OPTICAL DENSITY OF PMMA UNDER THE ACTION OF DEUTERONS WITH ENERGIES 4-150 keV S. P. Kapchigashev, V. P. Kovalev, UDC 539.125.4:541.15 E. S. Barkhatov, and V. A. Sokolov The measurement of the difference in the optical density of polymethyl methacrylate (PMMA) before and after irradiation is a widespread method of determination of the absorbed energy of high-intensity ionizing radiation. However, the principles of the variation of the optical density (AS) as a function of the characteristics of the radiation (LET, type of particles, eta.) have thus far been insufficiently studied [1-4]. In this work we investigated the change in the optical density of PMMA under the action of deuterons with an energy of 4-150 key. The method of irradiation was described earlier [5]. Plates of PMMA 1 mm thick were irradiated with deuterons of various energies and the change in the optical density observed on an USV-1 spectrophotometer at the wavelength 300 nm. A comparison of the dependence of the effective- ness of radiation chemical changes on the energy was conducted with an integral flux equal to 4.3 -1014 deuterons/cm2. It was preliminarily shown that in this region of fluxes AS is a linear function of the dose. The ranges of protons of the investigated energies are hundredths of a micron to units of microns, which is substantially less than the thickness of the PMMA plates. Therefore, the absorbed energy is proportional to the total energy of the particles E. The effectiveness of optical changes in n can be de- termined as n= AS/E. The values of n for various deuteron energies are presented in Table 1. From Table 1 it is evident that the effectiveness of the optical changes decreases substantially with increasing deuteron energy, which does not agree with the conclusions drawn in [3] with respect to low- energy particles. The increase in the effectiveness of radiation changes with decreasing dose of deuterons may be associated with a relative increase in the contribution of elastic nuclear collisions to the "ex- change" of energy. Here it must be assumed that elastic processes are significantly (more than three times) more effective in radiation chemical disruptions of polymethyl methacrylate than processes of ionization and excitation. This phenomenon must be taken into consideration in the practical use of poly- mer materials in the dosimetry of nuclear radiation. TABLE 1. Dependence of the Effectiveness of Optical Changes in PMMA on the Deuteron Energy E, key 71.cm2/MeV E,keV ibemz/MeV 4 11+0,5 50 3,4+0,2 10 6,6+1,0 100 3,9+0,2 25 3,7+0,6 150 3,6 LITERATURE CITED 1. Ya. I. Lavrentovich et al., in: Dosimetry and Radiation Processes in Dosimetric Systems [in Rus- sian], Fan, Tashkent (1972), p. 178. 2. K. Chadwick, Rad. Res., 44, 282 (1970). Translated from Atomnaya Energiya, Vol. 38, No. 1, p. 50, January, 1975. Original letter sub- mitted July 1, 1974. ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 62 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 3. G. Angstrom and L. Ehrenberg, in: Collection of Materials on the Symposium on Individual Prob- lems of Dosimetry [Russian translation], Atomizdat, Moscow (1962), p. 188. 4. D. Neufeld and W. Snyder, ibid., p. 33. 5. S. P. Kanchigashev et al., At. gnerg., 34, No. 4, 299 (1973). Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 COME CON NEWS PROVISIONAL INTERNATIONAL WORKTEAM P. M. Tyukhtin On February 23, 1973, authorized representatives of seven countries with membership in the Council for Economic Mutual Aid [COMECON] (viz. Bulgaria, Hungary, GDR, Poland, Rumania, USSR, Czecho- slovakia) signed an Agreement on setting up a Provisional International Scientific-Research Workteam to carry out reactor physics research on a VVER type critical assembly. The purpose of this research will be to devise and work out exact methods for design calculations relevant to VVER type reactors, and to elaborate straightforward and reliable techniques for handling variant calculations in the process of designing and operating reactors, and also to expedite research on perfecting methods in measurements and in the design of measuring equipment. The experimental research facilities available to the staff of this provisional international workteam will be a VVER type critical assembly (3R-6 assembly) located at the Central Physics Research Institute of the Hungarian Academy of Sciences. This critical assembly was started up in November, 1972. That was followed by a period during which technical staff personnel were trained on the job, and in February, 1973, the scientific staff of the provisional international research team got started on the experimental research program. A Scientific Council staffed by no more than three representatives from each country has been set up to provide scientific guidance for the activities of the research team, but each nation signatory to the Agreement has one vote. The Scientific Council schedules its sessions to gear into the work plan of the Council, but no more often than three times a year. These sessions are held in Budapest. Four sessions have been held to date: the first in February, 1972, the second in December, 1972, the third in June, 1973, and the fourth in March, 1974; a fifth session is scheduled for January, 1975. The head of the research team is the director of the Central Physics Research Institute, L. Mal. A detailed analysis of results achieved and of scientific topics being tackled is presented at meet- ings of specialists organized every eight months. To date two such conferences have been held, one in Czechoslovakia on the statics of VVER type reactors (October 31 through November 3, 1972), the second in Poland and dealing with reactor neutron statics (October 2-5, 1973). A third conference on VVgR physics is planned for December 2-7, 1974, in GDR. Three subteams have been set up to expedite the solution of some concrete problems. In the period intervening between sessions of the Scientific Council, these subteams and the research personnel working on the 3R-6 assembly are responsible for organizing their own work. Translated from Atomnaya Energiya, Vol. 38, No. 1, p. 51, January, 1975. ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 64 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 COLLABORATION DAYBOOK A conference of specialists of COMECON member-nations on standardization of radiation equipment and radiation protection equipment was held in Mamaia (Rumania) September 3-6, 1974. Drafts of COMECON standards applicable to modular lead shielding units were discussed and agreed upon, as well as draft recommendations on standardization referable to shielded dry boxes (types, basic parameters and dimensions), shielded gloveboxes (types, basic parameters and dimensions); y-therap'eutic equipment (basic parameters and general technical specifications); complex mobile laboratories for non- destructive testing and quality control work (general technical requirements); systems and devices for alarm annunciation and flaw detection signalling in radiation flaw detection work. Technical reports on recommendations referable to shielded cabinets or safes, packing sets for shipping radioactive materials safely, were heard and discussed. Draft recommendations on proper clas- sification of laboratories for handling sources of ionizing radiations, and general technical requirements applicable, were discussed; a draft glossary of terms and definitions in the field of radiation protection work was discussed and agreed upon, as were a work plan on standardization of radiation equipment and radiation protection equipment for the year 1975, and a draft plan on collaboration over the 1976-1980 period. The 14th session of the panel on nuclear electric power generating stations of the COMECON Per- manent Commission on Electric Power was held September 17-21, 1974, at Herceg Novi (Yugoslavia). Urgent problems in the development of nuclear power in COMECON member-nations and in Yugoslavia came under discussion at the session. Materials on "Equipment type related engineering safety valida- tions for installation and operation of nuclear power station equipment at the commissioning stage" and on "Standard types of operating report forms for nuclear power stations with VVER-440 power generating units" were approved. These documents enable those countries to go ahead with preparations on a high technical level to put nuclear power stations into service and to raise the safety levels of those power stations. Close attention was given to the development of power station equipment for nuclear power stations with VVER -1000 type reactors, in particular for expanding cooperation between COMECON mem- ber-nations in that area. A report entitled "Training of operating personnel for nuclear power stations," approved by the panel, is of considerable practical interest. The use of this material will be helpful in significantly improving the training of highly skilled cadres for service in COMECON member-nations, The 1975 work plan of the panel, envisaging research on such pressing topics as protection of the environ- ment, nuclear power station safety, and improvements in nuclear power equipment, was approved. The fourth session of the KNTS-RB (Scientific?technical coordinational council on radiation safety) was held in Leipzig (GDR), September 24-27, 1974. The council heard information on how the resolutions adopted at the )0CVIIth Session of COMECON on environmental conservation were being carried out, re- ports and communications on work being done under the collaboration program, including recommendations aiding physical design calculations of biological shielding for power stations with pressurized-water reac- tors; results of a comparison of personnel monitors and dosimetric systems; suggestions aimed at further Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 51-52, January, 1975. ? 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 65 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 development of the topic "Determination of volume of monitoring operations in radioactive wastes burial areas"; requirements on radiation safety when sources of ionizing radiations are used in medicine, and on general radiation safety criteria when radioactive isotopes are used in industry, and so forth. Proposals on the holding of a conference of specialists from COMECON member-nations, sometime in 1975 in Czechoslovakia, to deal with radiation safety problems in the context of operation of nuclear power stations and within the framework of a program of international intercalibration of whole-body y - radiation spectrometers, were discussed at this session. A draft drawn up by the IAEA leadership, en- titled "Estimates of collectivepopulation exposure dose," was discussed, and remarks were prepared for submission to the IAEA Secretariat, with special attention given to the most important measures to be taken by IAEA in 1975 in the area of radiation safety from the standpoint of the interests of KNTS-RB in this matter. The council reached agreement on a tentative agenda for the fifth session of KNTS-RB, and a draft work plan covering the 1975-1976 period. A conference of specialists on ways of developing techniques and equipment for cleanup of radioactive aerosols and gases from air-vented wastes was held September 30-October 4, 1974, in Leningrad. Results of research work on methods of trapping radioactive iodine by trapping from the vapor phase, and methods for analyzing radioiodine content, were discussed. The use of adsorbers packed with acti- vated charcoal and presenting not less than 1000 m2/g surface area and 0.4 m bed height, with a linear gas stream flow velocity of 0.3 to 0.4 m/sec in the adsorber, is recommended as a suitable means of trapping iodine. It was pointed out that active charcoal cannot be used if nitrogen oxides, ozone, fluorine, or other powerful oxidizing agents are present in the off-gases, and the same applies to admixtures of materials of high molecular weight. Specialists reported on research findings in studies of methods for determining the total radioactive iodine content in air and in off-gases vented from nuclear power stations, the iodine content by components, and the content of individual iodine compounds. The use of special cartridges (columns) filled with acti- vated charcoal such as used in gas chromatography was recommended for periodic determinations in the absence of nitrogen oxides or ozone. Continued research on developing distinct methods for analysis of iodine and alkyl iodides was deemed advisable, as well as further work on methods for testing the filtering capacity of materials employed. Comparative tests on specimens of filtering materials, using methods generally applied in the participating countries, were proposed. Attention was focused on how to remove radioactive noble gases and aerosols from off-gases vented from nuclear power stations, on how to design filtering devices, and also on how to work out a unified terminology referable to radioactive aerosols. Reports were heard from specialists on the results of work in studying regular patterns in the dis- semination of radioactive materials exhausted from the stacks of nuclear power stations. Concrete data on isotope make-up, on the concentrations and physicochemical characteristics of radioactive products, and also on models of the propagation of radioactive materials under conditions typical of short-term and con- tinuous discharges were discussed, with attention given to special features of the terrain and environment, wind conditions and variation, and the influence of those factors on scattering and propagation of radioactive pollutants through the ground layer of the atmosphere. Elaboration of a unified procedure, common to all COMECON member-nations, for the tolerance level of radioactive products in the neighborhood of industrial plants and power plants, was proposed. Long-term trends in the field of deactivation of radioactive aerosols and gases were also discussed. 66 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 ? Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 The seventh session of the KNTS on radioactive wastes and wastes deactivation was held in Lenin- grad, September 30 through October 4, 1974. Proposals sumitted by the delegations of the various countries dealing with research in the field of deactivation of liquid wastes, solid wastes, and gaseous wastes, and deactivation of contaminated surfaces in rooms and on equipment, came wider discussion. This research is to be conducted over the 1976-1980 period. These proposals were recommended as a basis in the preparation of a draft program for collaborative efforts in this area. The proposals envisage an extended range of efforts associated with processing and burial of radioactive wastes, including: processing of liquid radioactive wastes of low and medium levels of radioactivity; improvements in techniques and equipment for processing, immobilization, and burial of radio- active wastes of all levels; improvements in methods and equipment for averting radioactive contamination and spills, and for deactivating rooms and equipment in nuclear power stations, in research centers, and in nuclear fuel processing and reprocessing plants; investigations of techniques and equipment for cleanup of air discharges to get rid of radioactive aerosols and gases; investigations of the Danube River basin and of the Baltic Sea for detection and assessment of pollu- tion by radioactive materials. The results of developments in the technology of disposal of low-level and medium-level solid and immobilized wastes by burial in salt mine caverns, and also problems in shipping such wastes from the point of formation to the burial site, were discussed (in reports covering developmental work in this area by the GDR delegation); also results of research on physicochemical processes involving interaction of radioactive wastes and materials of underground strata, and the development of a method for preparing wastes for subterranean burial; data on research on applications of electrodialysis to cleanup of low-level radioactive wastes (research and development work by the USSR delegation). Resolutions were adopted on the appropriate use of these developments in the particular countries, and on recommendations relevant to the more advanced research trends in these fields. The council discussed a reference catalog of ion-exchange resins produced in COMECON member- nations and used in technological processes for cleanup and deactivation of liquid radioactive wastes. The catalog provides the characteristics of ion-exchange resins, defined according to unified evaluation pro- cedures adopted in the various countries. 67 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 INFORMATION: CONFERENCES AND MEETINGS THE NINTH WORLD ENERGY CONFERENCE Yu. I. Koryakin The ninth world energy conference was held September 23-27, 1974, Detroit (USA). Participating in the deliberations were over 4300 delegates from 80 countries, and from virtually all the major inter- national organizations concerned with power problems [COMECON (Council for Mutual Economic Aid), the European Economic Commission of UNO, the International Institute of Applied Systems Analysis, IAEA, the European Economic Commonwealth, etc.]. The Soviet delegation was headed up by the Minister of Power and Electrification P. S. Neporozhnii. This conference also functioned as an anniversary gathering: the year 1974 marked 50 years of the existence and activities of the World Power Organization. The US President G. Ford delivered an address inaugurating the conference, with the presentation of a World Comprehensive Energy Program entitled Interdependence Project. It is worth pointing out that one special feature of the conference was its timing following immediately upon the heels of the 1973-1974 energy crisis which broke out in the western countries and which affected international relations and adversely affected the economic situation in a number of countries. The con- ference consequently went beyond the framework of a simple forum for discussion of scientific and applied problems in the field of industrial power, power resources, and power utilization. In the discussions, reports, and floor discussion following presentations, allusion was frequently made to problems in the area of philosophy, politics, sociology, psychology, international collaboration, and so on. The slogan of the conference was "Economics and the environment in the light of future energy needs," itself a reflection of the topics around which 229 papers presented centered, as well as in char- acter with the discussion unfolding and the classification of the reports. All of the reports were grouped under the following headings and panels:* I Division. Population and Energy Resources. Panel 1. Population growth and population distribution (5). Panel 2. Power resources and power utilization (33). Panel 3. Distribution of resources (14). II Division. The Environment and Energy Availability. Panel 1. Quality of the air (12). Panel 2. Quality of the water (12). Panel 3. Utilization of land resources (5). Panel 4. Noise level (4). Panel 5. Esthetics (2). Panel 6. How the environment influences energy availability (20). III Division. Restoration of Energy Resources. Panel 1. Progress in the technology of energy resources recovery (20). Panel 2. Effect of resources recovery technology on the environment (8). IV Division. Energy Transformation. Panel 1. Progress in energy conversion technology (22). Panel 2. Effect of energy conversion on the environment (24). *The number of reports submitted and presented on a particular set of topics appears in parentheses. Translated from Atomnaya Energiya, Vol. 38, No. 1, pp. 53-56, January, 1975. 0 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission of the publisher. A copy of this article is available from the publisher for $15.00. 68 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 V Division. Energy Transport. Panel 1. Progress in energy transport technology (18). Panel 2. Effect of energy transport technology on the environment (3). VI Division. Utilization of Energy. Panel 1. Progress in energy utilization (21). Panel 2. Effect of energy utilization on the environment (6). There were 26 papers dealing specifically with nuclear power topics, and of these 23 dealt with reactor electric power problems and the remaining three with applications of reactor heat in desalination of sea- water, a possible role for nuclear power in the utilization of ocean resources and thermonuclear energy. Most of the papers on nuclear power fall under the heading of "Energy conversion" in the breakdown above. In practically all of the reports dealing with plans and forecasts for the development of power in the various countries, a decisive role was cut out for nuclear power. In the discussion of topics pertinent to nuclear power, attention was focused on macroscopic aspects of nuclear energy production: the scale of development and forecasting patterns, the fuel problem, and the fuel cycle in nuclear power systems. In contrast to preceding conferences of this series, here there was no place for descriptions of reactor types and nuclear power stations, reactor engineering or reactor technology. Attention was instead centered not so much on nuclear power stations per se as a means of generating electric power as on those factors and conditions governing the functioning of nuclear power stations (uranium resources and uranium mining, fabrication of fuel elements) or those factors and conditions accompanying the functioning of nuclear power plants (disposal of radioactive wastes by burial, nuclear power station safety topics, environmental effects of nuclear power stations). These topics also came under discussion in relation to the entire nuclear power grid, not just in relation to individual isolated nuclear power stations. In general, it should be stressed here that the systems approach applied in the discussion of energy problems typified this par- ticular conference. Reports dealing with nuclear power topics can be grouped arbitrarily under the following headings: 1. Scales and forecasts of nuclear power development. 2. The role of fast reactors and nuclear power structure in the future development of nuclear power, and alternative structures for nuclear power station systems. 3. Experience in the building and operation of nuclear power stations, new types of nuclear power stations and new projects and concepts. 4. Topics relating to the external fuel cycle in the nuclear power industry. 5. Nuclear power and the environment. The role played by nuclear power in making energy available throughout the world in the future (figured or extrapolated to the year 2000 as a rule) was the subject of papers presented by national dele- gations and by international organizations. Various authors advanced predictions of the scale of nuclear power development throughout the world, with a breakdown by large-scale geographic zones: Europe, North America, the Pacific zone, Central and South America, Asia and the Far East and New Zealand, Africa, and the Middle East, countries with a centralized planned economy. Data on some individual coun- tries were also presented. It was emphasized that the considerable rise in worldwide prices for crude oil, from the area of 21.2-23.8 dollars /ton to ?133 dollars /ton, brought on by the 1973 energy crisis, greatly enhanced the economic competitiveness of nuclear power stations. This found expression in the economic feasibility of using more expensive uranium (22 dollars/kg U308), in an appreciable drop in the economically justifiable unit power output of power generating units of nuclear power stations, and consequently an expansion of the demand for nuclear power stations on the world market, and also in the greater amount of interest displayed in building major nuclear power generating stations. All of this, as might be expected, will bring about an intensified tempo of development of nuclear power, and will lead to nuclear power making a significant contribution to the generation of electric power around the year 2000. On the whole, the fraction accounted for by nuclear power stations in total electric power generating capacity by the year 2000 will be anywhere from 50 to 83%, depending on the authors making the estimates. The last percentage figure, corresponding to a total power output of 5.3 billion kW, is a limiting figure, and is apparently on the high side. The range of 2.7 to 3.0 billion kW is judged more realistic. 69 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Declassified and Approved For Release 2013/09/25: CIA-RDP10-02196R000400050001-5 Fig. 1. Detroit. Cobo Hall (sports and exhibition complex housing the World Energy Conference) appears in foreground. Almost all of the authors pointed out the role that fast reactors can play in the future economy of uranium resources. The development of fast reactors continues to be regarded as a general developmental trend in nuclear power. But for the time being the inadequate level of technical preparation for widespread commercial exploitation continues to lend a low profile to fast reactors in the forecast nuclear power structure (accounting for no more than 30% of the total) at least till the end of the century. In other words, until the end of the century nuclear power will remain predominantly ?thermal," and no appreciable savings in uranium are expected from the use of fast breeders up to the year 2000 or thereabouts. Meanwhile, the cost of building such reactors is simply exorbitant at the present state of the art. For example, the build- ing of the fast liquid-metal LMFBR reactor with its 350 MW(e) rating, at Oak Ridge (USA), is now esti- mated at a total of 1.736 billion dollars. It was also emphasized in this context that the economic competitiveness of nuclear power stations with LWR type reactors holds its own even in the face of a doubling of uranium prices, and possibly even in the event that uranium prices increase three- or fourfold. There are on that account no special worries as to the long-term viability of LWR type thermal reactors, even looking at them outside of the question of fast breeders. But if effect