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1.
We develop a physico-mathematical model describing excitation and distribution of electromagnetic waves in an anisotropic waveguide or resonator in the three-dimensional case. We develop a theoretical approach for discretization of the Maxwell equations in an arbitrary medium in the presence of bounding walls of a waveguide or resonator. The resulting system of linear algebraic equations for the electric-field components in an inhomogeneous anisotropic medium is solved by the method of biconjugate gradient. The results of calculating the electric field lines in the cross section of an anisotropic insert of a rectangular waveguide are presented.  相似文献   
2.
Fullerene deuteride was obtained by the reaction of deuterium with solid palladium fulleride C60Pd4.9 under fairly mild conditions. The compound was identified by FD-MS, UV-Vis and IR spectroscopies, and TLC.Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 483–484, February, 1996  相似文献   
3.
Fine-structure fluorescence spectra have been recorded on selective laser excitation at 4.2 K for meso-tetraethylporphyrin (TEP), meso-tetrapropyl-porphyrin (TPP) and their derivatives with deuteriated NH groups. An interpretation of the spectra obtained is proposed on the basis of calculations of the normal vibrations of the molecules. It was noted that the interaction of the ethyl groups of TEP with the solvent leads to different orientations of these groups to the plane of the macrocycle, which leads to an increase in the number of lines in the frequency range 150–400 cm–1 and to their broadening.Translated from Teoreticheskie i Éksperimental'naya Khimiya, Vol. 26, No. 6, pp. 664–668, November–December, 1990.  相似文献   
4.
Institute of Molecular and Atomic Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 137–144, March–April, 1995.  相似文献   
5.
The corresponding 2,3-diphenyl[3,2-a]pyrimidinium salts were obtained by the condensation of 4,5-diphenyl-2-aminothiazole perchlorate with -diketones, -chlorovinyl ketones, -chlorovinyl aldehydes, and 1,1,3,3-tetraethoxypropane. The PMR spectra were used to prove the structures of the compounds obtained, particularly to select the structures of the isomeric salts obtained in the condensation with unsymmetrical -diketones, -chlorovinyl ketones, and -chlorovinyl aldehydes. As a rule, the latter give one isomer — the -unsubstituted (relative to the bridge nitrogen atom) derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 629–631, May, 1972.  相似文献   
6.
Russian Chemical Bulletin - The monomer [Cr3O(OCOCH=CH2)6]OH was produced by reaction of acrylic acid with fresh chromium hydroxide. This monomer was investigated by a number of physicochemical...  相似文献   
7.
    
Summary GLC-MS results have been obtained for acetates of partially methylated methyl 6-deoxyhexopyranosides that permit the positions of the OMe groups to be determined unambiguously and assignment to a definite stereoisomer to be made by means of T values.Pacific Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 457–459, July–August, 1974.  相似文献   
8.
A new potential donor of nitrogen monoxide, a binuclear iron sulfur nitroso complex, was prepared by exchange reaction of Na2Fe2(S2O3)2(NO)4 with pyridine-2-thiol in the presence of sodium thiosulfate at pH 12. The molecular and crystal structures of [Fe2(-SC5H4N)2(NO)4] were studied by X-ray diffraction analysis. The type of iron coordination by pyridine-2-thiol in the presence of a coordinated NO molecule was determined. In vacuum, the structure of the complex is destroyed, which is accompanied by NO evolution, while exposure to UV radiation results in decomposition of the complex and in a release of N2O.  相似文献   
9.
A new general reaction involving the thermal decomposition of Schiff bases of meso-formyloctaalkylporphyrins, which leads to porphyrins that contain a cyclopentane ring, was discovered. The optimum conditions in the synthesis of porphyrins with substituted and unsubstituted cyclopentane rings were worked out in the case of the thermolysis of Schiff bases of meso-formyletioporphyrin I, meso-formyletioporphyrin II, and octaethylporphyrin. The synthesized compounds were characterized by data from the electronic, PMR, and mass spectra.See [1] for communication 15.See [2, 3] for preliminary communications.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 479–484, April, 1984.  相似文献   
10.
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