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991.
992.
M. V. Fedin S. R. Shakirov P. A. Purtov E. G. Bagryanskaya 《Russian Chemical Bulletin》2006,55(10):1703-1716
The review summarizes the results of studies on specific features of spin relaxation of radicals in liquids in weak magnetic
fields.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1642–1654, October, 2006. 相似文献
993.
994.
The method of optical model analysis of generalized elastic scattering angular distributions (GESA) has been applied to heavy
ion scattering to derive fusion spin distributions. This method is used to reproduce the coupled channel fusion spin distributions.
When applied to experimental data, particularly to the fissile systems like16O +232Th, the method gives large mean square spin values in agreement with “anomalous” values derived from experimental fission
fragment anisotropies. 相似文献
995.
Lee-Fen Ko 《Journal of statistical physics》1988,52(3-4):795-813
The dispersion expansion for the spin correlation function in the two-dimensional Ising model with linear defects belowT
c is derived. The asymptotic behavior is computed by a steepest descent analysis. The lattice is divided into four domains with different asymptotic behaviors. In particular, the correlation length inside certain domains is a function of the defect. 相似文献
996.
V. I. Bondar Yu. M. Kukharskii Yu. P. Yampol'skii E. Sh. Finkelshtein K. L. Makovetskii 《Journal of Polymer Science.Polymer Physics》1993,31(10):1273-1283
Gas sorption properties, permeability coefficients, and diffusion coefficients of a series of norbornene polymers are presented. Introduction of the Si(CH3)3 group into the polynorbornene (PNB) backbone chain results in significant increases in glass transition temperature, permeability, and diffusion coefficient for a number of gases (H2, O2, N2, CO2, CH4, C2H6). The transport properties and sorption isotherms for poly(5-trimethylsilyl norbornene) (PTMSNB) are very similar to those for poly(vinyltrimethyl silane) (PVTMS), which contains the same side-chain group but differs from PTMSNB by the structure of its main chain. For another silicon-containing polymer poly[5-(1,1,3,3-tetramethyl-1,3-disilabutyl) norbornene] (PDSNB) having a bulkier side-chain group, the glass-transition temperature is decreased in comparison with that of PNB, presumably owing to self-plasticization. Both silicon-containing norbornene polymers (PTMSNB and PDSNB) have permeability coefficients for “rapid” gases like H2 or CO2 of about 102 Barrer. The high values of the Langmuir sorption capacity C′H for PTMSNB and PVTMS, as well as the high diffusivity and mobility of spin probes in these polymers, were attributed to a large free volume related to the bulky Si(CH3)3 groups attached directly to the main chain. © 1993 John Wiley & Sons, Inc. 相似文献
997.
分析各种极化的海夸克对对核子的自旋相关性质的作用. 并试图改进传统模型对质子自旋性质的计算. 相似文献
998.
Representations ofD
k
*
k
* for a quaternion division algebraD
k over a local fieldk are orthogonal representations. In this note we investigate when these orthogonal representations can be lifted to the corresponding
spin group. The results are expressed in terms of local root number of the representation. 相似文献
999.
R L Kamman K G Go F A Muskiet G P Stomp P Van Dijk H J Berendsen 《Magnetic resonance imaging》1984,2(3):211-220
Proton spin longitudinal (T1) and transverse (T2) relaxation and proton density studies were carried out on human fatty tissue and bovine white matter, both in the native state and after immersion in D2O. It is concluded that nuclear magnetic resonance signals from fatty tissue result mainly from methyl and methylene protons of hydrocarbons. No contribution from lipid protons could be detected for white matter, although it contains a high percentage of lipids. Imaging experiments, resulting in T1, T2, and proton density maps, support the results obtained with spectroscopic relaxation studies. 相似文献
1000.
Nitrosobenzene (NB) and nitroso-tetr-butane (NtB) were used to trap the photogenerated rhenium pentacarbonyl radical. Self trapped radicals and spin adducts were studied in detail by EPR spectroscopy. In methylene chloride, both nitroxide and anilino spin adducts can be observed with NtB at ?30°. In contrast, only the nitroxide spin adduct of nitrosobenzene was observed in either hexane, or methylene chloride solution. This solvent controlled spin adduct chemistry, can be explained in terms of the solute-solvent interaction. 相似文献