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1.
D. Fong J. H. Hamilton A. V. Ramayya J. K. Hwang C. Goodin K. Li J. Kormicki J. O. Rasmussen Y. X. Luo S. C. Wu I. Y. Lee A. V. Daniel G. M. Ter-Akopian G. S. Popeko A. S. Fomichev A. M. Rodin Yu. Ts. Oganessian M. Jandel J. Kliman L. Krupa J. D. Cole M. A. Stoyer R. Donangelo W. C. Ma 《Physics of Atomic Nuclei》2006,69(7):1161-1167
The hot bimodal fission of 252Cf is reexamined with new high-statistics data. We constructed a γ-γ-γ coincidence cube for binary fission and LCP-gated γ-γ matrix for ternary fission. By identifying the secondary fission fragments from their γ-ray transitions, we measured the yields for various fission splits. The normal neutron yield distribution is found to be
Gaussian for Xe-Ru. However, the binary fission split of Ba-Mo is found to exhibit a bimodal neutron distribution with the
“hot mode” corresponding to ≈3.1% of the total yield. In α ternary fission, the first measurements of yields for specific fission splits are presented. The Te-α-Ru and Xe-α-Mo neutron yields fit well with a single mode, but the Ba-α-Zr split shows evidence for an enhanced hot mode with an intensity of ≈13.8% of the normal mode.
The text was submitted by the authors in English. 相似文献
2.
G. M. Ter-Akopian A. V. Daniel A. S. Fomichev G. S. Popeko A. M. Rodin Yu. Ts. Oganessian J. H. Hamilton A. V. Ramayya J. Kormicki J. K. Hwang D. Fong P. Gore J. D. Cole M. Jandel J. Kliman L. Krupa J. O. Rasmussen I. Y. Lee A. O. Macchiavelli P. Fallon M. A. Stoyer R. Donangelo S. -C. Wu W. Greiner 《Physics of Atomic Nuclei》2004,67(10):1860-1865
Ternary fission of 252Cf was studied at Gammasphere using eight ΔE×E particle telescopes. Helium, beryllium, boron, and carbon light charged particles (LCPs) emitted with kinetic energy more than 9, 21, 26, and 32 MeV, respectively, were identified. The 3368-keV γ transition from the first 2+ excited state in 10Be was found and the population probability ratio N(2+)/N(0+) = 0.160 ± 0.025 was estimated. No evidence was found for 3368-keV γ rays emitted from a triple molecular state. For the first time, charge distributions are obtained for ternary fission fragments emitted with helium, beryllium, and carbon LCPs. 相似文献
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N. S. Prostakov A. V. Varlamov A. Hussein A. A. Fomichev N. A. Ryabova E. E. Stashenko 《Chemistry of Heterocyclic Compounds》1990,26(4):424-430
Spiro[4-azafluorene-9,1 cyclopropanes] were obtained by the reaction of 9-diazo-4-azafluorene with various alkenes in the form of a mixture of geometrical isomers differentiated according to the position of the substituents in the cyclopropane ring and also also according to position relative to the pyridine ring. In the reaction of 9-diazo-4-azafluorene with cyclopentanone, di(4-azafluorene-9 nyl) oxide is formed, while from its reaction with cyclohexanone, 2-oxo-spiro[4-azafluorene-9,1-cycloheptane] is obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 495–501, April, 1990. 相似文献
7.
N. S. Prostakov Hanna Bu Habib V. A. Rezakov A. A. Fomichev L. M. Kirillova V. K. Shevtsov 《Chemistry of Heterocyclic Compounds》1984,20(8):911-915
It was established that the side product that is formed in substantial amounts in the phenylation of -picoline by phenyllithium is 3-methyl-2-phenyl-5-(3-methyl-2-phenyl-3,4-dehydropiperidyl-6)pyridine — a structural analog of anabasine. Its structure was demonstrated by spectral methods and by chemical conversions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 115–119, August, 1984. 相似文献
8.
N. S. Prostakov I. V. Shendrik B. N. Anisimov A. V. Varlamov A. A. Fomichev S. Lavani-Édogiaverie 《Chemistry of Heterocyclic Compounds》1982,18(10):1085-1088
It was demonstrated by PMR spectroscopy that mixtures of N-oxides of 6- and 7-nitro derivatives are formed in the nitration of the N-oxides of 3-methyl-2- and 4-azafluorenes. The products were deoxygenated to give nitro derivatives of 2- and 4-azafluorenes. The N-oxides of nitro-substituted azafluorenes were converted to salts of the aci forms by the action of alkali.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1396–1399, October, 1982.The authors thank K. F. Turchin for his assistance in recording the spectrum of nitration product VI at 200 MHz. 相似文献
9.
M. A. Ryashentseva Kh. M. Minachev V. V. Fomichev V. A. Bardin 《Russian Chemical Bulletin》1986,35(6):1120-1122
Conclusions Rhenium oxides with perovskite structure of the general formula
where BIII=Y and Sm, and Ba3LaZnReWO12 containing Re(VII), exhibit catalytic activity in hydrogenation of ethyl acetate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1236–1238, June, 1986. 相似文献
10.
New data on experimental implementation of the magnetohydrodynamic (MHD) parachute configuration in an air flow with Mach number M = 6 about a flat plate are considered. It is shown that MHD interaction near a flat plate may transform an attached oblique shock wave into a normal detached one, which considerably extends the area of body-incoming flow interaction. This effect can be employed in optimizing return space vehicle deceleration conditions in the upper atmosphere. 相似文献