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排序方式: 共有191条查询结果,搜索用时 437 毫秒
1.
A noiselike fine structure of ferromagnetic resonance spectra in magnetic powders was investigated after ultrasonic treatment. Magnetic interactions between particles are proved to have an influence upon the fine structure formation. After decreasing dipole-dipole magnetic interactions in dilute suspension a special order appears in fine-structure spectra, which is generally the same for different systems. 相似文献
2.
3.
S.A. Dikanov V.F. Yudanov R.I. Samoilova Yu.D. Tsvetkov 《Chemical physics letters》1977,52(3):520-525
Data on the trapping site of radicals in zeolite α-cages have been obtained by the analysis of modulation effects in the electron spin echo of CH2OH radicals produced by irradiation in A-type zeolite with adsorbed methyl alcohol. 相似文献
4.
Anastacia A. Layeva Galina N. Lipunova Valerii N. Charushin 《Journal of fluorine chemistry》2007,128(7):748-754
A new approach for the synthesis of fluorinated 1H-quinazolin-4-ones and 4-substituted quinazolines has been developed. 6-Fluoro-1H-quinazolin-4-ones were obtained by intramolecular cyclization of fluorine-containing S-ethyl N-benzoylisothioureas. Nucleophilic substitution reactions at positions 2 and 7, as well as alkylation at 1-position of quinazolinones were investigated. In addition, the synthesis of fluorine-containing 4-aminoquinazolines was carried out. 相似文献
5.
N. F. Yudanov E. G. Boguslavskii I. I. Yakovlev S. P. Gabudar 《Russian Chemical Bulletin》1988,37(2):200-203
1. | A method has been developed for the intercalation of solid substances from solutions in organic solvents into graphite fluoride C2Fx. |
2. | Molecules of inserted paramagnetic copper complexes and nitroxyl radicals assume oriented positions between the structural layers in graphite fluoride. |
3. | The planes of molecules of bis-chelate Cu(II) complexes with acetylacetone, o-hydroxyquinoline, and phenylsalicylaldimine were determined to lie parallel to the C2Fx planes. |
4. | A method has also been suggested for the preparation of samples from C2Fx·yA compounds with a higher degree of texturizing (more nearly complete orientation) than can be achieved by pelletizing. |
6.
O. P. Alemskaya V. M. Lelevkin A. V. Tokarev V. A. Yudanov 《High Energy Chemistry》2005,39(4):263-267
The synthesis of ozone from oxygen in a cylindrical ozonizer operating under surface discharge conditions with a plasma electrode was studied. The conditions of ozone synthesis were optimized. The dependence of ozone concentration and specific energy consumption on gas pressure in the plasma electrode and on distance between the coils of a corona electrode was determined. The results were compared with data obtained with the use of classical surface barrier discharge.__________Translated from Khimiya Vysokikh Energii, Vol. 39, No. 4, 2005, pp. 307–311.Original Russian Text Copyright © 2005 by Alemskaya, Lelevkin, Tokarev, Yudanov. 相似文献
7.
Compounds of fluorographite C2F intercalated with acetonitrile have been investigated by nuclear magnetic resonance. The appearance of anisotropic molecular diffusion accompanied by a phase transition of the melting type has been discovered in the quasi-two-dimensional system of guest molecules.Institute of Inorganic Chemistry, Academy of Sciences of the USSR, Siberian Branch. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 2, pp. 79–83, March–April, 1991. 相似文献
8.
N. A. Yazykov A. D. Simonov V. K. Ermolaev V. F. Yudanov 《Reaction Kinetics and Catalysis Letters》1991,43(2):565-570
A method to determine rates for gaseous and liquid transfer of moisture in the process of mass transfer in porous materials is suggested. The data obtained agree well with the theoretical concepts about liquid transfer of moisture under contact of two porous bodies.
. .相似文献
9.
Alexander M. Schneider Luyao Lu Eric F. Manley Tianyue Zheng Valerii Sharapov Tao Xu Tobin J. Marks Lin X. Chen Luping Yu 《Chemical science》2015,6(8):4860-4866
We report the properties of a new series of wide band gap photovoltaic polymers based on the N-alkyl 2-pyridone dithiophene (PDT) unit. These polymers are effective bulk heterojunction solar cell materials when blended with phenyl-C71-butyric acid methyl ester (PC71BM). They achieve power conversion efficiencies (up to 5.33%) high for polymers having such large bandgaps, ca. 2.0 eV (optical) and 2.5 eV (electrochemical). Grazing incidence wide-angle X-ray scattering (GIWAXS) reveals strong correlations between π–π stacking distance and regularity, polymer backbone planarity, optical absorption maximum energy, and photovoltaic efficiency. 相似文献
10.
In this study, new biodegradable and biocompatible amphiphilic polymers were obtained by modifying the peripheral hydroxyl groups of branched polyethers and polyesters with organosilicon substituents. The structures of the synthesized polymers were confirmed by NMR and GPC. Organosilicon moieties of the polymers were formed by silatranes and trimethylsilyl blocks and displayed hydrophilic and hydrophobic properties, respectively. The effect of the ratio of hydrophilic to hydrophobic organosilicon structures on the surface activity and biological activity of macromolecules was studied, together with the effect on these activities of the macromolecules’ molecular weight and chemical structure. In particular, the critical micelle concentrations were determined, the effect of the structure of the polymers on their wetting with aqueous solutions on glass and parafilm was described, and the aggregation stability of emulsions was studied. Finally, the effect of the polymer structures on their antifungal activity and seed germination stimulation was examined. 相似文献