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1.
L. S. Azhgirey V. V. Arkhipov S. V. Afanasiev V. K. Bondarev V. N. Zhmyro L. S. Zolin V. I. Ivanov A. Yu. Isupov A. A. Kartamyshev V. A. Kashirin V. I. Kolesnikov V. A. Kuznetsov V. P. Ladygin N. B. Ladygina A. G. Litvinenko S. G. Reznikov P. A. Rukoyatkin A. Yu. Semenov I. A. Semenova G. D. Stoletov G. Filipov A. N. Khrenov N. P. Yudin 《Physics of Atomic Nuclei》2003,66(4):690-699
The invariant differential cross section, the tensor analyzing power A yy , and the vector analyzing power A y for the reaction 9Be(d, p)X are measured at an initial deuteron momentum of 4.5 GeV/c and a proton detection angle of about 80 mrad. The data obtained for the differential cross section are consistent with the results of measurements at 3.5 and 5.78 GeV/c and a proton emission angle of 2.5°. The values found for the tensor analyzing power A yy are compared with similar data obtained previously for the deuteron-fragmentation process occurring on a carbon target at various values of the initial deuteron momentum and leading to proton emission at zero angle. The data on the differential cross section for the reaction 9Be(d, p)X can be satisfactorily described within the relativistic impulse approximation by using standard deuteron wave functions; however, the approach based on this conceptual framework proves to be inadequate in dealing with data on the tensor analyzing power. These results indicate that it is necessary either to change the method for describing the relativistic deuteron or to take into account additional mechanisms. 相似文献
2.
We show how methods for estimating the concentration function of the sum of independent random variables can be used to obtain estimates of the concentration function for the values of additive functions under suitable conditions. Previously obtained estimates of the concentration function are consequences of the estimate obtained in the present paper for functions from of the class under consideration. 相似文献
3.
E. N. Popova V. E. Yudin N. V. Kukarkina T. A. Kostereva I. V. Gofman V. V. Kudryavtsev 《Russian Journal of Applied Chemistry》2006,79(3):439-444
A series of foamed organoplastics based on a combination of foamed fully aromatic polyimide binders and Arimid T polyimide felt were prepared. New composite foamed organoplastics reinforced with montmorillonite nanoparticles were prepared using commercially available aromatic monomers. 相似文献
4.
CV Tomy D Pal SS Banerjee S Ramakrishnan AK Grover S Bhattacharya MJ Higgins G Balakrishnan McK Paul 《Pramana》2002,58(5-6):925-935
The weakly pinned single crystals of the hexagonal 2H-NbSe2 compound have emerged as prototypes for determining and characterizing the phase boundaries of the possible order-disorder
transformations in the vortex matter. We present here a status report based on the ac and dc magnetization measurements of
the peak effect phenomenon in three crystals of 2H-NbSe2, in which the critical current densities vary over two orders of magnitude. We sketch the generic vortex phase diagram of
a weakly pinned superconductor, which also utilizes theoretical proposals. We also establish the connection between the metastability
effects and pinning. 相似文献
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5-Methoxy-3-carbethoxyindoles are nitrated primarily in the 4 position. Replacement of the methoxy group by an acetoxy group leads to a change in orientation — only the 6 isomer is obtained. In the case of the similarly constructed 5-hydroxyindoles, monosubstitution cannot be accomplished under various conditions, and only the 4,6-dinitro derivative is formed. The synthesis of the corresponding amines by reduction of the nitro compounds is described.See [1] for communication XXXVIII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1646–1653, December, 1973. 相似文献
8.
[reaction: see text] A new class of cyclohexane-based P,N-ligands is readily obtained through aziridine ring opening with suitable phosphorus nucleophiles under acidic conditions. trans-1-Amino-2-diphenylphosphinocyclohexane is resolved with tartaric acid to give the final product in >99% ee. The new ligands show high stability toward oxidation at the phosphorus atom. 相似文献
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Functionalized branched aziridines can be prepared in high yields and with high levels of regioselectivity using unprotected aziridines as nitrogen sources in palladium-catalyzed allylic amination. High levels of enantioselectivity can be achieved with BINAP on palladium. This methodology allows for strategic placement of an aziridine-containing fragment within a complex molecule environment for further elaboration. 相似文献