Journal of Nuclear Energy (1954)最新文献

{"title":"Deuteron dissociation in nuclear scattering","authors":"A.G. Sitenko","doi":"10.1016/0891-3919(59)90009-9","DOIUrl":"10.1016/0891-3919(59)90009-9","url":null,"abstract":"","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 4","pages":"Pages 241-243"},"PeriodicalIF":0.0,"publicationDate":"1959-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(59)90009-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87391229","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}

{"title":"Fast neutron capture in 238U and 232Th","authors":"R.C. Hanna,&nbsp;B. Rose","doi":"10.1016/0891-3919(59)90003-8","DOIUrl":"10.1016/0891-3919(59)90003-8","url":null,"abstract":"<div><p>The cross-sections for neutron capture in ²³⁸U and ²³²Th have been measured by an activation method for mono-kinetic incident neutrons in the energy range 30–1000 keV.</p></div>","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 4","pages":"Pages 197-205"},"PeriodicalIF":0.0,"publicationDate":"1959-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(59)90003-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81596917","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}

{"title":"Branching ratio of 242mAm decay","authors":"R.W. Hoff,&nbsp;E.K. Hulet,&nbsp;M.C. Michel","doi":"10.1016/0891-3919(59)90006-3","DOIUrl":"10.1016/0891-3919(59)90006-3","url":null,"abstract":"<div><p>The branching ratio, <em>β</em>⁻/<em>EC</em> = 5·1 ± 0·1, for ^{242<em>m</em>}Am decay has been measured by determining the relative amounts of the decay products, ²⁴²Cm and ²⁴²Pu formed. The 16 hour ^{242<em>m</em>}Am was produced by neutron irradiation of ²⁴¹Am in the Materials Testing Reactor. A pile neutron cross-section of 620 ± 65 barns for the reaction ²⁴¹Am(n, γ)^242mAm was measured.</p></div>","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 4","pages":"Pages 224-228"},"PeriodicalIF":0.0,"publicationDate":"1959-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(59)90006-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82071165","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}

{"title":"The effect of a current boundary condition on control rod effectiveness","authors":"Bertram Wolfs","doi":"10.1016/0891-3919(58)90007-X","DOIUrl":"10.1016/0891-3919(58)90007-X","url":null,"abstract":"","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Pages 63-65"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90007-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84946651","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}

{"title":"On calculations for cylindrical reactors","authors":"V.K. Saulev","doi":"10.1016/0891-3919(58)90016-0","DOIUrl":"10.1016/0891-3919(58)90016-0","url":null,"abstract":"","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Pages 100-101"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90016-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86197031","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}

{"title":"Production of weighable amounts of 99Tc by neutron irradiation of molybdenum","authors":"Vict.I. Spitsyn,&nbsp;A.F. Kuzina","doi":"10.1016/0891-3919(58)90035-4","DOIUrl":"10.1016/0891-3919(58)90035-4","url":null,"abstract":"","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Page 176"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90035-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89396796","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}

{"title":"The (p,n) reaction on lithium and the ground state of the 6Be nucleus","authors":"G.F. Bogdanov,&nbsp;N.A. Vlasov,&nbsp;S.P. Kalinin,&nbsp;B.V. Rybakov,&nbsp;V.A. Sidorov","doi":"10.1016/0891-3919(58)90022-6","DOIUrl":"10.1016/0891-3919(58)90022-6","url":null,"abstract":"<div><p>The time-of-flight method has been used to study the neutron spectra from the reactions of ⁶Li and ⁷Li with 9 MeV protons. Neutron groups were observed corresponding to transitions to the ground state of ⁶Be and to the three lower states of ⁷Be, as well as a continuous distribution of low-energy neutrons due to more complex reactions. Observation of the group of neutrons from the reaction ⁶Li(<em>p,n</em>)⁶Be is the first experimental evidence of the existence of the ⁶Be nucleus. The <em>Q</em>-value of the reaction ⁶Li(<em>p,n</em>)⁶Be is equal to −5·2 MeV and the width of the ground state of ⁶Be is less than 0·3 MeV. The differential cross-sections for neutron formation were measured at angles of 0, 15, 30, 60 and 120°.</p></div>","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Pages 148-155"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90022-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89567785","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}

{"title":"The mass distribution of fragments resulting from the fission of 235U, 238U and 238Pu induced by 14·6 MeV neutrons","authors":"A.N. Protopopov,&nbsp;G.M. Tolmachev,&nbsp;V.N. Ushatskii,&nbsp;R.V. Venediktova,&nbsp;I.T. Krisuk,&nbsp;L.P. Rodionova,&nbsp;G.V. Jakovleva","doi":"10.1016/0891-3919(58)90033-0","DOIUrl":"10.1016/0891-3919(58)90033-0","url":null,"abstract":"","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Page 176"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90033-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"104757933","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}

{"title":"Neutron flux distributions in media separated by a cylindrical boundary","authors":"A.E. Glauberman,&nbsp;I.I. Talianskyi","doi":"10.1016/0891-3919(58)90012-3","DOIUrl":"10.1016/0891-3919(58)90012-3","url":null,"abstract":"<div><p>Expressions are derived for the neutron flux distribution due to a point source on the axis of cylindrical symmetry of two coaxial media of different properties. The two-group approximation is used, and the transfer of neutrons between the two media is represented by the introduction of fictitious neutron source distributions over the boundary. Expressions are given for the fast and slow-neutron flux distributions in both media.</p></div>","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Pages 84-90"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90012-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78314484","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}

{"title":"Sur un nouveau traitement multigroupe de la diffusion des neutrons dans les milieux reproducteurs Application a la correction des perturbations subies par les flux thermiques et rapides au voisinage d'un reflecteur, d'une source de neutrons ou d'un reseau different","authors":"J. Martelly","doi":"10.1016/0891-3919(58)90002-0","DOIUrl":"10.1016/0891-3919(58)90002-0","url":null,"abstract":"<div><p><strong>Part 1</strong>—If the equilibrium between thermal and fast neutrons propagated in a reproducing medium is perturbed by a neighbouring medium (a reflector, a fast neutron source, a system with a different lattice, etc.) the spatial distribution of each of the groups is also perturbed: it no longer obeys the elementary diffusion equation: <span><math><mtext>ϵ</mtext><msup><mi></mi><mn>ϕ</mn></msup><mtext> + </mtext><mtext>K − 1</mtext><mtext>M</mtext><msup><mi></mi><mn>2</mn></msup><mtext>ϵ = 0</mtext></math></span></p><p>On the other hand, the linear combination <span><span><span><math><mtext>T = </mtext><mtext>σ</mtext><mtext>i</mtext><mtext>1</mtext><mtext>3</mtext><mtext>λ</mtext><msub><mi></mi><mn>i</mn></msub><mtext>ε</mtext><msub><mi></mi><mn>i</mn></msub></math></span></span></span> covering all the neutron groups, no matter how many, is very little affected by these perturbations: this combination satisfies an equation (No. 22) which differs from the above diffusion equation by the addition of corrective terms, modifying the Laplacian, which are proportional to the perturbations of the spectral distribution. Discussion shows that the effect of these corrective terms is negligible in practice for natural uranium lattices (Fig. 3); it is also small for enriched piles.</p><p>A physical interpretation of these results is based on the following statement: the gradient of <em>T</em> is equal to the total neutron current.</p><p>The introduction of this quantity naturally simplifies certain problems in permitting the use of one group theory (if necessary with slight corrections) to give a better precision than the classical two group theory.</p><p>In particular the systematic errors in the measurements of the Laplacian due to the conditions at the extremities of the medium under study, are avoided.</p><p><strong>Part 2</strong>—The practical application of the properties of the function <em>T</em> assumes an experimental knowledge of the function. It is defined for a large number of groups, whereas the actual measurements are often limited to the activities of detectors in the thermal and resonance energy ranges: <em>T</em> can in fact be deduced from them if one knows the diffusion law which applies during slowing down. The calculation is carried through for two particular cases of perturbation,—a neighbouring source of fissions, and a neighbouring reflector.</p><p>The results may be expressed in a two group formula (equation 46 for example) by means of the weighing coefficients, functions of the space co-ordinates—which must be applied to the quantities <em>q</em>_<em>n</em> and <em>q</em>_<em>r</em> which are proportional to the two measured activities. It is more convenient to employ the ratio <em>h</em> of these activities (or, what amounts to the same thing, the “cadmium ratio”) since this does not presuppose an absolute calibration of the detectors.</p><p><em>T</em> is then expressed (41) by the measure ","PeriodicalId":100812,"journal":{"name":"Journal of Nuclear Energy (1954)","volume":"8 1","pages":"Pages 1-17"},"PeriodicalIF":0.0,"publicationDate":"1958-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0891-3919(58)90002-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77275045","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}