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101.
Ya. A. Vereshchagina E. A. Ishmaeva A. A. Gazizova D. V. Chachkov M. G. Voronkov 《Russian Journal of General Chemistry》2007,77(1):36-39
Conformational analysis of 1,4-heterophosphinanes in solution, based on a combination of the dipole moment and Kerr effect methods, molecular mechanics, and quantum-chemical calculations (B3LYP/6-31G*) was performed. It was established that, regardless the second heteroatom in the six-membered phosphorus-containing heterocycle (oxygen, sulfur, or silicon) and phosphorus coordination, these compounds prefer a chair conformation with an equatorial exocyclic phenyl substituent. 相似文献
102.
Ya. A. Vereshchagina A. Z. Alimova D. V. Chachkov E. A. Ishmaeva R. I. Baichurin V. M. Berestovitskaya 《Russian Journal of General Chemistry》2013,83(9):1771-1774
Polarity and structure of ethyl α-nitrocinnamates have been studied by means of dipole moments method and quantum-chemical calculations. These compounds exist in the form of Z-isomers in solution, that is, nitro group and benzene ring are cis-positioned. 相似文献
103.
Ya. A. Vereshchagina A. Z. Alimova D. V. Chachkov E. A. Ishmaeva O. I. Artyushin E. V. Sharova A. E. Klimovitskii R. R. Khanafieva 《Russian Journal of Organic Chemistry》2014,50(6):796-799
The polarity and conformations of 2-aminophenyl-, 2-aminobenzyl-, and 2-nitrobenzyl(diphenyl)-phosphine oxides were studied by the dipole moment method, IR spectroscopy, and quantum chemical calculations. 2-Aminophenyl- and 2-aminobenzyl(diphenyl)phosphine oxides were found to exist preferentially as conformers with intramolecular hydrogen bond. 2-Nitrobenzyl(diphenyl)phosphine oxide is likely to be represented by equilibrium mixture of three conformers in which the phosphoryl and nitro groups are oriented syn or anti with respect to the \(PC_{sp^3 } C_{sp^2 } \) fragment. 相似文献
104.
E. A. Ishmaeva A. P. Timosheva A. A. Gazizova D. V. Chachkov Ya. A. Vereshchagina V. E. Kataev N. V. Timosheva 《Russian Journal of General Chemistry》2008,78(7):1350-1353
The method of dipole moments and theoretical calculations (DFT B3LYP/6-31G*) were used for structural assessment of silatranes N[CH2(RMeC6H2)O]3SiR1 containing planar fragments in the six-membered semirings. They are endo structures with transannular N→Si interaction which involves, along with nitrogen and silicon, oxygen atoms adjacent to silicon. 相似文献
105.
E. A. Ishmaeva Ya. A. Vereshchagina D. V. Chachkov O. S. Vasil’eva E. S. Ostroglyadov A. A. Nikonorov I. A. Litvinov D. B. Krivolapov A. Z. Alimova V. M. Berestovitskaya 《Russian Journal of General Chemistry》2012,82(5):911-920
Polarity of 2-(1-methylbenzimidazol-2-yl)-1-phenyl- and -1,2-diphenyl-1-nitroethenes was determined and their structure was studied using electronic and 1H, 13C NMR spectroscopy, dipole moments measuring, XRD analysis, and quantum-chemical calculations. It was shown that the 2-(1-methylbenzimidazol-2-yl)-1-nitro-1-phenylethene has Z-configuration both in crystal and solution. The nitro group and benzimidazole substituent in its molecule are removed from the plane of the double bond. For 1,2-diphenyl-1-nitroethene E-structure is typical. 相似文献
106.
Ya. A. Vereshchagina D. V. Chachkov A. Z. Alimova E. A. Ishmaeva S. F. Malysheva 《Russian Journal of Organic Chemistry》2012,48(10):1320-1322
Conformational analysis of bis(2-phenylalkyl)phosphine selenides was performed by the dipole moment method and quantum-chemical calculations. Bis(2-phenylpropyl)phosphine selenide was found to exist as a mixture of several conformers, the most energetically favorable of which being characterized by gauche (non-eclipsed) orientation of the P=Se and $C_{sp^3 } - C_{sp^3 } $ bonds. 相似文献
107.
Bukharov S. V. Bakhdyrova D. F. Tagasheva R. G. Burilov A. R. Litvinov I. A. Chachkov D. V. Vereshchagina Ya. A. 《Russian Chemical Bulletin》2021,70(10):1964-1972
Russian Chemical Bulletin - N-Benzylation of acylhydrazones of the hydroxybenzaldehyde series with 3,5-di-tert-butyl-4-hydroxybenzyl acetate was performed at room temperature in the absence of acid... 相似文献
108.
Badma N. Mankaev Valeriia A. Serova Dr. Mikhail A. Syroeshkin Anna Ya. Akyeva Dr. Alexey V. Sobolev Dr. Andrei V. Churakov Dr. Elmira Kh. Lermontova Dr. Mikhail E. Minyaev Dr. Yury F. Oprunenko Dr. Maxim V. Zabalov Kirill V. Zaitsev Dr. Galina S. Zaitseva Prof. Dr. Sergey S. Karlov 《欧洲无机化学杂志》2023,26(11):e202200690
A series of novel tetrylenes based on three 2,6-bis(2-hydroxyphenyl)pyridines 4 a – 4 c have been obtained by the reaction of Lappert's tetrylenes E[N(SiMe3)2]2 (E=Ge, Sn) with corresponding tridentate pyridine-linked phenol-based ligands. It was found that the structure of the ligand and the size of the atom of the group 14 element drastically affect the structure of the reaction product. Ligand 4 c with a bulky tert-butyl group leads to monomeric tetrylenes, while ligands with less bulky groups lead to bis-ligand derivatives of M(IV) (M=Ge, Sn) and a coordination polymer. Also, derivatives of germanium (IV) and tin (IV) were obtained by the metathesis reaction of MCl4 (M=Ge, Sn) with lithium phenoxides. The compositions and structures of the novel compounds were established by elemental analysis and 1H, 13C, 119Sn ( 5 – 7 ), 1H DOSY ( 6 ) NMR spectroscopy, in the solid state by X-ray diffraction analysis (germylene 10 , stannylene 6 , Ge4+ compound 8 , Sn4+ compound 7 ) and 119Sn Mössbauer spectrum of tin complex 6 . All the synthesized tetrylenes are monomeric. Tetrylenes 6 and 10 were characterized by cyclic voltammetry. A study of the redox behavior of 6 , 10 by cyclic voltammetry on a glassy carbon working electrode in acetonitrile solution of 0.1 M Bu4NPF6 as a supporting electrolyte showed that these compounds can be both oxidized and reduced electrochemically in the accessible potential range. 相似文献