Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology最新文献_第3页

Measurements and calculations of the Doppler effect on the reactions 238U(n, γ), 235U(n, f) and 239Pu(n, f) with neutrons in the energy range 0–25 keV 238U(n， γ)、235U(n, f)和239Pu(n, f)与能量0-25 keV中子反应的多普勒效应测量与计算

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90130-3

J.L. Perkin, P. Fieldhouse, A. Brickstock, A.R. Davies

{"title":"Measurements and calculations of the Doppler effect on the reactions 238U(n, γ), 235U(n, f) and 239Pu(n, f) with neutrons in the energy range 0–25 keV","authors":"J.L. Perkin, P. Fieldhouse, A. Brickstock, A.R. Davies","doi":"10.1016/0368-3230(66)90130-3","DOIUrl":"https://doi.org/10.1016/0368-3230(66)90130-3","url":null,"abstract":"<div>Spherical samples, 2 cm in diameter, of 238U, 235U and 239Pu were irradiated in turn at various temperatures ranging from 170 to 770°K in a central cavity of a spherically symmetrical SbBe photoneutron source. The 298U(n, γ) reaction rate was measured by counting the 239U activity produced and the (n, f) reactions were monitored by counting the fission neutrons emitted. The spherical symmetry of the apparatus was chosen to minimize any effects of thermal expansion and to facilitate the comparison of the results obtained with those from a computer calculation based on a programme developed by Brissenden and Durston. In this programme a statistical distribution of resonances based on resolved resonance data is tabulated over a fine energy mesh. This tabulation was used in a 4-region slowing down calculation resulting in a region-dependent neutron spectrum from which the particular reaction rates at various temperatures were obtained.</div>","PeriodicalId":100815,"journal":{"name":"Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology","volume":"20 11","pages":"Pages 921-937"},"PeriodicalIF":0.0,"publicationDate":"1966-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0368-3230(66)90130-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90027443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Asymptotic solutions in transport theory part I—One velocity with isotropic scattering 输运理论的渐近解第i - 1部分:各向同性散射的速度

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90131-5

A.K. Ghatak, F. Ahmed

{"title":"Asymptotic solutions in transport theory part I—One velocity with isotropic scattering","authors":"A.K. Ghatak, F. Ahmed","doi":"10.1016/0368-3230(66)90131-5","DOIUrl":"https://doi.org/10.1016/0368-3230(66)90131-5","url":null,"abstract":"<div>We report here some results of an extensive series of calculations on the asymptotic behaviour of a neutron pulse injected into a slab and a sphere using monoenergetic transport theory with isotropic scattering cross section in the laboratory system. These results are compared with the infinite medium solutions with exp (iBx) spatial dependence. Two definitions of buckling are considered and the corresponding extrapolation distances are calculated; both the quantities are of considerable interest in the study of neutron thermalization. The characteristic angular peaking of neutrons leaking from slabs of extremely small thicknesses has been found. The spatial variation of the fundamental mode eigenfunction has been calculated and it has been found that the flux shape (except very close to the boundary) can be fitted accurately to the fundamental mode of the scalar Helmholtz equation ▽2Φ + B2Φ = 0. The results obtained from simple diffusion theory, with extrapolation distance assumed to be given by the Milne value, (independent of the size of the assembly), has been found to compare well with the exact calculations of the fundamental mode eigenvalue for thicknesses exceeding one mean free path. The theoretical results are compared with the recent pulsed neutron experiments in fast non-multiplying non-moderating assemblies.</div>","PeriodicalId":100815,"journal":{"name":"Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology","volume":"20 11","pages":"Pages 939-951"},"PeriodicalIF":0.0,"publicationDate":"1966-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0368-3230(66)90131-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90124937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Optimum control of thermal processes in a nuclear reactor 核反应堆热过程的最优控制

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90152-2

I.M. Kurbatov, M.P. Leonchuk, A.S. Trofimov

引用次数: 0

Attenuation of reactor radiations in serpentine sand 蛇纹石砂中反应堆辐射的衰减

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90141-8

G.A. Vasil'ev, A.P. Veselkin, Yu.A. Egorov, G.G. Moiseev, Yu.V. Pankravev

引用次数: 0

Diffusion of uranium in molybdenum, niobium, zirconium and titanium 铀在钼、铌、锆和钛中的扩散

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90144-3

L.V. Pavlinov, A.I. Nakonechnikov, V.N. Bykov

{"title":"Diffusion of uranium in molybdenum, niobium, zirconium and titanium","authors":"L.V. Pavlinov, A.I. Nakonechnikov, V.N. Bykov","doi":"10.1016/0368-3230(66)90144-3","DOIUrl":"https://doi.org/10.1016/0368-3230(66)90144-3","url":null,"abstract":"<div>An investigation was made of the diffusion of uranium in molybdenum, niobium, zirconium and titanium. The diffusion coefficients were established by measuring the integral activity of the residue of the sample, using the α-radiation of uranium enriched up to 90 per cent with 236U, at temperatures of 1500–2000°C (for molybdenum and niobium) and 915–1200°C (for zirconium and titanium).The temperature dependence of the diffusion coefficients was presented as <math><mtext>D</mtext><msub><mi></mi><mn>Mo</mn></msub><msup><mi></mi><mn>U</mn></msup><mtext> = 7.60 × 10</mtext><msup><mi></mi><mn>3</mn></msup><mtext> exp(− 76400/RT)cm</mtext><msup><mi></mi><mn>2</mn></msup><mtext>/sec;</mtext></math><math><mtext>D</mtext><msub><mi></mi><mn>Nb</mn></msub><msup><mi></mi><mn>U</mn></msup><mtext> = 8.90 × 10</mtext><msup><mi></mi><mn>−2</mn></msup><mtext> exp(− 76800/RT)cm</mtext><msup><mi></mi><mn>2</mn></msup><mtext>/sec;</mtext></math><math><mtext>D</mtext><msub><mi></mi><mn>Zr</mn></msub><msup><mi></mi><mn>U</mn></msup><mtext> = 7.77 × 10</mtext><msup><mi></mi><mn>−5</mn></msup><mtext> exp(− 25800/RT)cm</mtext><msup><mi></mi><mn>2</mn></msup><mtext>/sec;</mtext></math><math><mtext>D</mtext><msub><mi></mi><mn>Ti</mn></msub><msup><mi></mi><mn>U</mn></msup><mtext> = 4.90 × 10</mtext><msup><mi></mi><mn>−4</mn></msup><mtext> exp(− 76400/RT)cm</mtext><msup><mi></mi><mn>2</mn></msup><mtext>/sec;</mtext></math>The substantial differences between the diffusion mobility and activation energy values of molybdenum and niobium on the one hand and zirconium and titanium on the other are probably due to defects in the crystal lattice, such as excess vacancies in zirconium and titanium due to polymorphic transformation.</div>","PeriodicalId":100815,"journal":{"name":"Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology","volume":"20 11","pages":"Pages 1027-1030"},"PeriodicalIF":0.0,"publicationDate":"1966-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0368-3230(66)90144-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90027441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Time-dependent spectra in heavy water 重水中随时间变化的谱

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90136-4

P. Wydler

引用次数: 0

Fast neutron radiative capture cross sections of Re and Ta Re和Ta的快中子辐射俘获截面

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90150-9

V. Kononov, Yu.Ya. Stavisskiį

引用次数: 0

Change in the spectrum of fast neutrons after passing through aluminium, paraffin and aqueous media 快中子通过铝、石蜡和水介质后光谱的变化

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90151-0

G. G. Doroshenko, V. Fedorov, E. S. Leonov

引用次数: 0

Dynamic behaviour of a stagewise liquid-liquid extraction process 逐级液-液萃取过程的动力学特性

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90132-7

A. Apelblat, M. Faraggi

引用次数: 4

Cold neutron effects in graphite diffusion measurements 石墨扩散测量中的冷中子效应

Journal of Nuclear Energy. Parts A/B. Reactor Science and Technology Pub Date : 1966-11-01 DOI: 10.1016/0368-3230(66)90128-5

J.A. Dejuren, V.A. Swanson

引用次数: 0