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The crystal structure was found for the Ni(II) complex with the nitroxyl radical derivative of 3-imidazoline L=C10H13N2O2F3 and 1-butanol C4H9OH with the formula NiL2(n-C4H9OH)2 (a=10.907(2), b=16.769(5), c=12.321(3) Å, =96.33(2), =120.36(1), =106.3(2)o, V = 1780.7(7) Å3, dcalc=1.32 g/cm3, space group P1, Z=2, R=0.072). The structure was molecular in nature. Octahedral coordination of the nickel ion was found with the oxygen and nitrogen atoms of two bidentate L in the equatorial plane [Ni–O, 2.13 Å (av.); Ni–N, 1.99 Å (av.)] and the oxygen atoms [Ni–OOH, 2.13 Å (av.)] of the OH groups of the alcohol molecules in the axial positions. The rather strong hydrogen bonds between the coordinated OH groups of the alcohol and oxygen atoms of the
groups of the adjacent complex molecules (O...O, 2.78–2.84 Å) delineate layers, in which the distances between the paramagnetic sites of adjacent molecules Ni... are shorter than the intramolecular distances and much shorter than the analogous distances between adjacent layers. On the whole, this structure is similar to those of analogous compexes with other alcohols previously studied.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 2, pp. 119–125, March–April, 1993. 相似文献
4.
E. V. Tretyakov A. S. Bogomyakov E. Yu. Fursova G. V. Romanenko V. N. Ikorskii V. I. Ovcharenkoa 《Russian Chemical Bulletin》2006,55(3):457-463
The molecular and crystal structures of porphyrexides, viz., 4-amino-2-imino-(1) and (Z)-2-amino-4-bromoimino-5,5-dimethyl-4,5-dihydro-1H-imidazole 1-oxyls (7), and their diamagnetic precursors were determined. Compound 1 is kinetically unstable because it is oxidized with atmospheric oxygen to form (E)-1,2-bis[1-amino-1-(cyanoimino)-2-methyl-propan-2-yl]diazene 1,2-dioxide.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 441–447, March, 2006. 相似文献
5.
Kiskin M. A. Shvedenkov Y. G. Ikorskii V. N. Romanenko G. V. Ovcharenko V. I. 《Russian Chemical Bulletin》2003,52(1):265-266
The reaction of FeII and FeIII salts with tetrabutylammonium squarate in an aqueous solution gives rise to a new molecular magnet (T
c = 8.6 K). 相似文献
6.
E. V. Tretyakov S. E. Tolstikov G. V. Romanenko Yu. G. Shvedenkov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2005,54(9):2169-2181
A new approach to the synthesis of polyfunctional pyrazolyl-substituted nitronyl nitroxides was developed based on the presynthesized
pyrazole derivatives prepared by 1,3-dipolar cycloaddition. The structures of the resulting mono-and biradicals were confirmed
by X-ray diffraction.
Dedicated to Academician A. L. Buchachenko on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2105–2116, September, 2005. 相似文献
7.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 1, pp. 93–99, January–February, 1992. 相似文献
8.
2-Chloro-3-formylquinoxaline was synthesized from 2-chloro-3-methylquinoxaline by the Kröhnke method, and the properties of its phenylhydrazone were studied. It was found that 2-Y-3-formylquinoxalines display an anomalously low reactivity as compared with 2-Y-benzoylquinoxalines (Y=H, OH, Cl) in the synthesis of pyrazolo[3,4-b]quinoxalines.See [1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 852–856, June, 1973. 相似文献
9.
A way to determine the form of an analytical signal without accounting of the base line is described. It is based on subtraction of two peaks. The validity of correction of the base line inclination with the help of a linear function is indicated. The ability to determine the true form of the analytical signal in case of overlapping signals is proved. The approach was applied to define the degree of non-additivity of the analytical signal and the character of change of the peak shape as a function of concentration. 相似文献
10.
Quantum chemical study of the appearance of the “α-effect” in35Cl NQR spectra of chloromethylsilanes
We consider the connection between the electron distribution in ClCH2MX1X2X3 molecules (M = C, Si) calculated by the CNDO/2 method and the experimental35Cl NQR frequencies. We show that the ratio of the NQR frequencies for chloromethylsilanes and their organic analogs can be explained on the basis of ideas concerning the totality of induction and conjugation effects influencing the population of the orbital of the chlorine atom which participates in formation of the C-Cl bond.Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 26, No. 2, pp. 241–244, March–April, 1990. 相似文献