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Reductive decomposition followed by hydrolysis of 5-(,-dicarethoxy--acetylamino) ethylbenz-2, 1, 3-selenadiazole gives -(3, 4-diaminophenyl)alanine.For Part XLVII see [1]. 相似文献
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A. L. Nivorozhkin L. E. Konstantinovskii L. E. Nivorozhkin V. I. Minkin T. G. Takhirov O. A. D'yachenko D. B. Tagiev 《Russian Chemical Bulletin》1990,39(2):271-278
1H and13C NMR, x-ray structural analysis, and magnetic moment measurements have shown that in 5-thio(seleno)pyrazolealdiminate complexes of nickel(II) based on tetradentate ligands containing the fragment, with n=2, flattening of the chelate unit takes place in solution and in the solid state. A similar structure in which the diamine metal-containing ring has the twist-chair conformation is observed for the crystals of the complexes with n=4. For the complexes with n=4 in solution at a temperature below –50°C, rapid (on the NMR time scale) interconversion of the flattened (P) (S=0) and pseudotetrahedral (T) (S=1) structures is observed, not accompanied by inversion of the tetrahedral configuration of the metal atom. At temperatures above –50°C, in addition to the low-barrier reactions (T) (P), conversion of the seven-membered saturated metal-containing ring and inversion of the tetrahedral configuration of the Ni atom with activation barriers of 48–51 kJ/mole are observed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 327–335, February, 1990. 相似文献
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V. Kh. Kravtsov Yu. M. Chumakov S. A. D'yachenko V. N. Biyushikin M. I. Bureneva T. I. Malinovskii 《Journal of Structural Chemistry》1990,31(2):311-317
Institute of Applied Physics, Academy of Sciences of the Moldavian SSR and Leningrad Pharmaceutical Chemistry Institute. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 2, pp. 146–153, March–April, 1990. 相似文献
7.
G. G. D'yachenko 《Journal of Structural Chemistry》1993,34(1):68-73
A method is proposed for introducing scaled corrections to a harmonic force field to take account of vibrational anharmonicity. All the spectra were satisfactorily described by the introduction of only three scaling coefficients in the case of methane and ethane isotopomers.P. N. Lebedev Institute of Physics, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 1, pp. 77–82, January–February, 1993. 相似文献
8.
A. B. Zolotoi S. V. Konovalikhin P. M. Lukin O. A. D'yachenko S. P. Zil'berg O. E. Nasakin 《Chemistry of Heterocyclic Compounds》1988,24(10):1166-1171
The Michael condensation of 1,1,2,2-tetracyanoethane with 3-methyl-4-benzylideneisoxazolin-5-one having the Z configuration leads to a heterocyclic spiran with retention of the cis orientation of the phenyl and keto groups. The deviations of the series of bond angles of the spiran from the standard values, the abnormal lengths of the C-C bonds adjacent to the gem-dicyano group, and the appearance of nonbonding >C=O(...)CN interactions and conjugation effects in the enaminonitrile fragment are discussed.For Communication 10, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1404–1410, October, 1988. 相似文献
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Benzo-2, 1, 3-thiadiazole (I) undergoes chloromethylation with dichlorodimethyl ether in the presence of anhydrous aluminum chloride with the predominant formation of 4, 7-di(chloromethyl)benzo-2, 1, 3-thiadiazole (II). Bases and pseudobases (paraformaldehyde, hexamethylenetetramine, dimethylformamide) exert an inhibiting influence on this reaction. In the presence of these substances, a mixture of compound II and 4-(chloromethyl)benzo-2, 1, 3-thiadiazole (III) is formed, or else no reaction takes place. The structures of compounds II and III has been shown by their reductive decomposition to o-diamines described in the literature. The high reactivity of the chlorine in the chloromethyl group has enabled various new derivatives of benzo-2, 1, 3-thiadiazole to be obtained by its replacement with hydroxy, thiocyanato, di(-hydroxyethyl)amino, di(-chloroethyl)amino, formyl, and carboxy groups.For communication XLVIII, see [11]. 相似文献
10.
S. V. Konovalikhin G. V. Shilov O. A. D'yachenko M. Z. Aldoshina R. N. Lyubovskaya R. B. Lyubovskii 《Russian Chemical Bulletin》1992,41(10):1819-1826
The compositions and structures of two new organic metals based on ET [where ET = bis(ethylenedithio)tetrathiafulvalene], viz., (ET)2[Hg(SCN)Cl2], with a metal-dielectric transition temperature (Tm-d) of 35°K, and (ET)2[Hg(SCN)2Br], with Tm-d = 140°K, were established by x-ray diffraction analysis. The crystal structures of the investigated compounds are similar to the structure of the previously studied organic metal (ET)2[Hg(SCN)2Cl] with Tm-d = 50°K. The principal crystallographic data for (ET)2[Hg(SCN)Cl2] are as follows: a = 36.64(1), b = 8.300(4), c = 11.798(1) Å, = 89.91(3)°, V = 3588.1(9) Å3, space group Cc, Z = 4, dcalc = 2.05 g/cm3. The principal crystallographic data for (ET)2[Hg(SCN)2Br] are as follows: a = 37.088(14), b = 8.338(3), c = 11.738(5) Å, = 89.71(3)°, V = 3629.6(8) Å3, space group C2/c, Z = 8, dcalc = 2.15 g/cm3. A characteristic feature of the crystal structure of the investigated compounds is alternation of the anion and cation layers along the a axis of the crystal. In the cation layer of the k type the ET are interconnected by shortened S...S intermolecular contacts (3.39–3.58 Å). The [Hg(SCN)3–nXn]– anions (X = Cl, Br; n = 1, 2) form polymeric chains with one or two bridged SCN groups. A tendency for a decrease in the metal-dielectric transition temperature with a decrease in the volume of the anion is detected in the (ET)2[Hg(SCN)3–nXn] salts, where X = Cl and Br, and n = 1 and 2.Institute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2323–2331, October, 1992. 相似文献