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71.
The eigen frequencies of radial pulsations of neutron stars are calculated in a strong magnetic field. At low densities we use the magnetic BPS equation of state (EOS) similar to that obtained by Lai and Shapiro while at high densities the EOS obtained from the relativistic nuclear mean field theory is taken and extended to include strong magnetic field. It is found that magnetized neutron stars support higher maximum mass whereas the effect of magnetic field on radial stability for observed neutron star masses is minimal.  相似文献   
72.
It has been shown that in lipid dispersions thionin causes the formation of heterogeneous structures with the production of lipid-enriched clusters melting at elevated temperatures. This effect of thionin depends on the type of acidic lipid. It has also been established that thionin causes the aggregation and intermembrane exchange of lipid material between two populations of liposomes possessing individual thermodynamic characteristics.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, Fax 627071. Brigham Young University, Provo, Utah, USA. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 78–82, January–February, 1994.  相似文献   
73.
Institute of Inorganic Chemistry, Academy of Sciences of the USSR, Siberian Branch. Institute of Organic Chemistry, Academy of Sciences of the USSR, Siberian Branch. Translated from Zhurnal Strukturnoi Khimii, Vol. 28, No. 5, pp. 73–80, September–October, 1987.  相似文献   
74.
The reaction of 5-amino-1,2,3-thiadiazol-4-carbothioamides with methyl iodide basically generates -diazo-S-methylthioimidates and -carbothioimidolates. It is shown that the reactivity of the latter increases when either alkyl or aryl substituents are introduced at the nitrogen atom of the carbothioamide groupTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 979–984, July, 1992.  相似文献   
75.
The electronic structure of the phenol molecule in the gas phase was studied by X-ray emission spectroscopy (using the O-Kα and C-Kα spectra). MNDO calculations were performed, which made it possible to construct theoretical spectra and interpret experimental spectra. The structure of the molecular orbitals of phenol was compared with those of benzene and water. The π-interaction of the phenyl fragment with the oxygen-containing substituent was investigated. The contribution of the 2p atomic orbital of the oxygen atom to the π-HOMO of phenol is considerably less than that to lower-lying orbitals. For Part 3, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2187–2193, December, 1997.  相似文献   
76.
The reactions of the natural lichen metabolite, (+)-usnic acid, with a series of commercially available polyfluoroolefins (tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropene, perfluoro-2-methylpent-2-ene, and 1,2-dichlorooctafluorocyclohex-1-ene) afford its 7-O-polyfluoroalkyl and perfluorovinyl ethers. Dedicated to the memory of Academician N. N. Vorozhtsov on the 100th anniversary of his birth. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1198–1202, June, 2007.  相似文献   
77.
Flavones 2′,5′-dimethoxyflavone, 3′-methoxy-4′,5′-methylenedioxyflavone, 3′,4′-dimethoxyflavone, 5,6,2′,3′,6′-pentamethoxyflavone, and 5,6,2′,3′,5′,6′-hexamethoxyflavone; salicylates, methyl-4-methoxysalicylate and peonol; and bisbibenzyl polyphenol riccardin C were isolated for the first time from the acetone extract of the aerial part of Primula macrocalyx Bge. The content of free and total fatty acids was determined by GC and GC—MS. Palmitic (16:0), octadecatetraenoic 18:4 (6,9,12,15), linoleic 18:2 (9,12), and α-linolenic 18:3 (9,12,15) were the principal acids from the aerial part of Primula macrocalyx. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 457–460, September-October, 2008.  相似文献   
78.
The reaction of (+)‐car‐2‐ene ( 4 ) with chlorosulfonyl isocyanate (=sulfuryl chloride isocyanate; ClSO2NCO) led to the tricyclic lactams 6 and 8 corresponding to the initial formation both of the tertiary carbenium and α‐cyclopropylcarbenium ions (Scheme 2). A number of optically active derivatives of β‐amino acids which are promising compounds for further use in asymmetric synthesis were synthesized from the lactams (see 16, 17 , and 19 – 21 in Scheme 3).  相似文献   
79.
The review discusses recent advances in the field of acid-catalyzed intra- and intermolecular transformations of pinane terpenoids and their oxygen-containing derivatives.  相似文献   
80.
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