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21.
V. N. Korneev P. M. Sergienko V. A. Shlektarev V. M. Aul’chenko M. A. Bukin V. M. Titov B. P. Tolochko M. R. Sharafutdinov A. V. Zabelin E. I. Litvinov A. M. Matyushin V. G. Stankevich M. A. Sheromov O. V. Naida A. A. Vazina 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(1):99-104
To modernize the DICSI station, new hardware and software have been created according to the conditions of the operating storage ring “Sibir’-2” beam channel. The recording system has been successfully tested on the operating channel of the storage ring VEPP-3 (Budker Institute of Nuclear Physics Siberian Branch, Russian Academy of Sciences, Novosibirsk) using the time-resolved “diffraction cinema” technique in studying real biological objects in the static and dynamic modes of data accumulation. At the DICSI station, structural changes in medical and biological objects are permanently investigated. The specific structure dimensions of these objects are in the nanometric range. 相似文献
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J.D. Dutson D. Litvinov M.R.J. Gibbs Y. Inaba H. Muraoka K. O’Grady 《Journal of magnetism and magnetic materials》2006
In this paper, we discuss two key aspects of magnetisation reversal in magnetic thin films with perpendicular anisotropy. Firstly, a study has been made of the additional field required to erase data written perpendicular to a thin film recording disk as the linear data density is increased. It has been found that an increase in data density from 40 to 360 kfci results in an increase of 1.25 kOe in the field required to erase the data. Secondly, the effect of varying the level of exchange coupling by co-sputtering CoCrPt samples with SiO2 has been studied using a characterisation technique that is independent of the self-demagnetising field. It has been found that the samples are fully exchange de-coupled when the film contains >9.8% SiO2 and the activation volume of reversal remains constant for higher levels of SiO2. 相似文献
24.
R. M. Vafina A. T. Gubaidullin O. N. Kataeva I. A. Litvinov Yu. G. Shtyrlin E. N. Klimovitskii 《Russian Journal of Organic Chemistry》2006,42(10):1563-1567
Conformationally heterogeneous 2-substituted 1,3-dithiacyclohept-5-enes (R = Ph, Me, t-Bu), which exist in solution as chair and boat conformers, react with dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate with high exo-diastereoselectivity: only the chair conformer is involved. The steric structure of 4-methyl-3,5-dithia-9,10-diazabicyclo[5.4.0]undeca-7,10-diene was determined by X-ray analysis. Its crystal packing and supramolecular structure were also analyzed. 相似文献
25.
V. D. Dyachenko S. G. Krivokolysko V. N. Nesterov Yu. T. Struchkov V. P. Litvinov 《Russian Chemical Bulletin》1996,45(10):2405-2410
The reaction of cyano(cyclohexylidene)thioacetamide with cyanothioacetamide or malononitrile andN-methylmorpholine yieldsN-methylmorpholinium 6-amino-3,5-dicyano-1,4-dihydropyridine-4-spirocyclohexane-2-thiolate. Its structure was established based on the results of alkylation and X-ray structural analysis.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2535–2540, October, 1996. 相似文献
26.
27.
Bredikhin A. A. Lazarev S. N. Bredikhina Z. A. Savel"ev D. V. Vandyukova I. I. Gubaidullin A. T. Litvinov I. A. 《Russian Chemical Bulletin》2003,52(4):846-852
Crystalline specimens of homochiral and racemic glycidyl p-toluenesulfonate were studied by IR spectroscopy, differential scanning calorimetry, and X-ray diffraction analysis. The melting phase diagram of glycidyl p-toluenesulfonate was constructed. The stacking effect in the crystals of the racemic sulfonate is responsible for a more dense molecular packing, with the result that a heterochiral type of crystallization becomes more favorable. 相似文献
28.
A. M. Shestopalov Yu. A. Sharanin I. A. Aitov V. N. Nesterov Yu. T. Struchkov V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1991,27(8):872-878
Highly regioselective reactions of pyridinium ylides with tetracyanoethylene occur via an AdN-E mechanism to form Z-isomers of 3-aroyl-3-(1-pyridinio)-1,1,2-tricyano-2-propenides-1, corresponding in structure to 1,4-ylides with maximum charge separation. If the unsaturated nitrite starting material contains a nucleofugal group 1,2-elimination predominates over 1,3-elimination.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1094, August, 1991. 相似文献
29.
I. A. Litvinov O. N. Kataeva D. R. Sharafutdinova B. Ya. Teitel'baum 《Russian Chemical Bulletin》1988,37(2):262-264
Conclusions The geometric parameters of the molecules of the main cyclic-fraction component contained in a polysulfide oligomer synthesized from 2,2-dichlorodiethylformal were determined. The cyclic structure assigned to this compound according to mass spectrometric data was confirmed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 338–340, February, 1988.The authors thank A. Kh. Plyamovatyi for-useful discussion of the present paper. 相似文献
30.
Mamedov V. A. Kalinin A. A. Gubaidullin A. T. Litvinov I. A. Azancheev N. M. Levin Ya. A. 《Russian Journal of Organic Chemistry》2004,40(1):114-123
3-(-Chlorobenzyl)-1,2-dihydroquinoxalin-2-one reacts with anions derived from acetylacetone, benzoylacetone, dibenzoylmethane, malononitrile, ethyl acetoacetate, and ethyl cyanoacetate to give the corresponding 3-(-R,R'CH-benzyl)-1,2-dihydroquinoxalin-2-ones which undergo intramolecular cyclocondensation to functionally substituted pyrrolo[1,2-a]quinoxalines on heating in boiling acetic acid. The reaction of 3-(-chloro-p-nitrobenzyl)-1,2-dihydroquinoxalin-2-one with acetylacetone anion directly leads to the corresponding pyrrolo[1,2-a]quinoxaline, without heating in acetic acid. 相似文献