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排序方式: 共有510条查询结果,搜索用时 375 毫秒
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V. Bradnova M. M. Chernyavsky L. Just S. P. Kharlamov A. D. Kovalenko M. Haiduc K. A. Kotel’nikov V. A. Krasnov V. G. Larionova F. G. Lepekhin A. I. Malakhov G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova N. A. Salmanova B. B. Simonov S. Vokal P. I. Zarubin 《Physics of Atomic Nuclei》2003,66(9):1646-1650
A physical program of irradiation of emulsions in beams of relativistic nuclei named the BECQUEREL Project is reviewed. It is destined to study in detail the processes of relativistic fragmentation of light radioactive and stable nuclei. The expected results would make it possible to answer some topical questions concerning the cluster structure of light nuclei. Owing to the best spatial resolution, the nuclear emulsions would enable one to obtain unique and evident results. The most important irradiations will be performed in the secondary beams of He, Be, B, C, and N radioactive nuclei formed on the basis of JINR Nuclotron beams of stable nuclei. We present results on the charged state topology of relativistic fragmentation of the 10B nucleus at low energy-momentum transfers as the first step of the research. 相似文献
3.
M. I. Adamovich V. Bradnova S. Vokal S. G. Gerasimov V. A. Dronov P. I. Zarubin A. D. Kovalenko K. A. Kotel'nikov V. A. Krasnov V. G. Larionova F. G. Lepekhin A. I. Malakhov G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova N. A. Salmanova B. B. Simonov M. M. Chernyavsky M. Haiduc S. P. Kharlamov L. Just 《Physics of Atomic Nuclei》2004,67(3):514-517
New results concerning the topology of the fragmentation of relativistic nuclei 7Li and 10B are presented. A program is proposed for studying the cluster structure of stable and radioactive nuclei. The use of emulsions in the investigation of nuclear clustering in the fragmentation of light nuclei at energies are in excess of 1 GeV per nucleon is discussed. 相似文献
4.
Balashov A. L. Danov S. M. Krasnov V. L. Chernov A. Yu. Ryabova T. A. 《Russian Journal of General Chemistry》2002,72(5):744-747
In the neutral systems formaldehyde-water-alcohol (methanol, ethanol, ethylene glycol) at 25°C, formaldehyde is preferentially present as hemiacetals. The mean equilibrium constants of step polycondensation of formaldehyde are calculated. 相似文献
5.
Krasnov P. O. Kuzubov A. A. Romanova T. A. Avramov P. V. 《Russian Journal of Coordination Chemistry》2004,30(9):634-638
The geometry and the electronic structure of iron porphyrinate complexes with various heterocyclic molecules in the fifth coordination position and a CO molecule in the sixth position were studied by density functional theory calculations. In the series of complexes with furan, imidazole, and pyrimidine, the bond between the Fe atom and CO is weakened due to the decrease in the overlap of the corresponding AOs. 相似文献
6.
I. O. Konstantinov B. V. Zatolokin N. N. Krasnov Yu. G. Sevastyanov L. S. Volkova 《Journal of Radioanalytical and Nuclear Chemistry》1976,31(2):487-493
Procedures for determining traces of calcium, titanium, vanadium, chromium, iron, copper, niobium, molybdenum and tungsten
in tantalum are described utilizing 11 MeV proton activation. The instrumental method of analysis with the use of a Ge(Li)
detector and the radiochemical separation of the corresponding fractions are described. The formula for the calculation of
the concentration of traces with the use of thick target yields is given. Experimental data on the thick target yields of
radioisotopes44Sc,52Mn,56Co,65Zn,93mMo,96Tc are presented. Based on the experimental data, the detection limits are estimated at 1–10 ppb for the above mentioned metal
traces in tantalum. The successful solution of the task of the simultaneous determination of nine elements in tantalum confirms
the wide applicability of proton activation analysis. 相似文献
7.
A. L. Balashov V. L. Krasnov S. M. Danov A. Yu. Chernov A. V. Sulimov 《Journal of Structural Chemistry》2001,42(3):398-403
An MNDO calculation gave the formation enthalpies of the components of equilibrium mixtures in concentrated aqueous acid solutions of formaldehyde. The results of this study suggest that intramolecular cyclization of linear oligomers with 5 and 9 CH2O units, respectively, is the most plausible mechanism of formation of cyclic oligomers of formaldehyde — trioxane and tetraoxane. Ring protonation by the hydroxonium ion with ring opening is the most energetically favorable route of cyclic acetal decomposition. 相似文献
8.
Krasnov V. P. Levit G. L. Korolyova M. A. Bukrina I. M. Sadretdinova L. Sh. Andreeva I. N. Charushin V. N. Chupakhin O. N. 《Russian Chemical Bulletin》2004,53(6):1253-1256
The influence of the reaction conditions (solvent, base) on the diastereoselectivity of acylation of (±)-3-methyl-2,3-dihydro-4H-1,4-benzoxazine with (S)-naproxen and N-tosyl-(S)-proline chlorides was studied. The highest diastereoselectivity was observed for the reaction carried out in benzene in the presence of aliphatic tertiary amines. 相似文献
9.
10.
Adamovich MI Aggarwal MM Alexandrov YA Andreeva NP Anson ZV Arora R Avetyan FA Badyal SK Basova E Bazarov IK Bhalla KB Bhasin A Bhatia VS Bogdanov VG Bubnov VI Burnett TH Cai X Carshiev DA Chasnicov IY Chernova LP Chernyavski MM Eligbaeva GZ Eremenko LE Gaitinov AS Ganssauge ER Garpman S Gerassimov SG Grote JG Gulamov KG Gupta SK Gupta VK Heckman HH Huang H Jacobsson B Judek B Kachroo S Kalyachkina GS Kanygina EK Karabova M Kharlamov SP Kitroo S Koss T Krasnov SA Kumar V Lal P Larionova VG 《Physical review D: Particles and fields》1993,47(9):3726-3732