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31.
B. A. Arbuzov Z. G. Isaeva M. G. Belyaeva V. V. Ratner O. N. Kataeva I. A. Litvinov V. A. Naumov 《Russian Chemical Bulletin》1992,41(1):117-119
Oxidation of 2-carene by lead tetraacetate in acetic acid afforded p-menth-1(10),2-dien-7-ol, 2-acetyl-6,6-dimethylbicyclo[3.1.0]hexane, p-menth-2-ene-1,7-diol, p-menth-1-ene-3,7-diol, and 2-(m-tolyl)propanol-2.Deceased.A. M. Butlerov Scientific Research Chemical Institute, V. I. Ul'yanov-Lenin Kazan' State University, 420008 Kazan. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 147–150, January, 1992. 相似文献
32.
33.
I.?S.?TerekhovaEmail author a?A.?Yu.?Manakov V.?V.?Feklistov Yu.?A.?Dyadin V.?YU.?Komarov D.?Yu.?Naumov 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(3-4):207-211
X-ray powder diffraction studies were performed of the polyhydrates, formed at positive temperature in swelled grains of carboxylic cation-exchange resins in the form of tetraisoamylammonium (cross-linked tetraisoamylammonium polyacrylates, differing in the degree of cross-linking: 1, 2 and 3%). It was shown that the polyhydrates exist as the crystalline phase under specific conditions, determined earlier by DTA technique. Diffraction patterns of the samples, recorded at the temperature +3 ± 1 °C, indicate that the polyhydrates crystallize in hexagonal symmetry, the unit cell parameters are close to a=12.25 Å, c=12.72 Å and do not depend significantly upon the degree of cross-linking. The suppositions were made concerning the size of hydrate crystallites, formed in the swelled grains of the studied resins.This revised version was published online in July 2005 with a corrected issue number. 相似文献
34.
I. A. Litvinov O. N. Kataeva V. A. Naumov R. P. Arshinova B. A. Arbuzov 《Russian Chemical Bulletin》1989,38(1):63-66
Conclusions X-ray structure analysis shows that for 4,5;7,8(4,4 -dimethyl-6,6-di-tert-butyl)-dibenzo-6H-2-diethylamino-2-thiono-1,3,2-dioxaphosphocine, the boat-chair conformation of Cs symmetry with an equatorial diethylamino group occurs in the crystal.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 74–77, January, 1989. 相似文献
35.
The syntheses, crystal structures determined by single-crystal X-ray diffraction, and characterizations of new Mo(6) cluster chalcobromides and cyano-substituted compounds with 24 valence electrons per Mo(6) cluster (VEC = 24), are presented in this work. The structures of Cs(4)Mo(6)Br(12)S(2) and Cs(4)Mo(6)Br(12)Se(2) prepared by solid state routes are based on the novel [(Mo(6)Br(i)(6)Y(i)(2))Br(a)(6)](4)(-) (Y = S, Se) discrete units in which two chalcogen and six bromine ligands randomly occupy the inner positions, while the six apical ones are fully occupied by bromine atoms. The interaction of these two compounds with aqueous KCN solution results in apical ligand exchange giving the two first Mo(6) cyano-chalcohalides: Cs(0.4)K(0.6)(Et(4)N)(11)[(Mo(6)Br(6)S(2))(CN)(6)](3).16H(2)O and Cs(0.4)K(0.6)(Et(4)N)(11)[(Mo(6)Br(6)Se(2))(CN)(6)](3).16H(2)O. Their crystal structures, built from the original [(Mo(6)Br(i)(6)Y(i)(2))(CN)(a)(6)](4)(-) discrete units, will be compared to those of the two solid state precursors and other previously reported Mo(6) cluster compounds. Their redox properties and (77)Se NMR characterizations will be presented. Crystal data: Cs(4)Mo(6)Br(12)S(2), orthorhombic, Pbca (No. 61), a = 11.511(5) A, b = 18.772(5) A, c = 28.381 A (5), Z = 8; Cs(4)Mo(6)Br(12)Se(2), Pbca (No. 61), a = 11.6237(1) A, b = 18.9447(1) A, c = 28.4874(1) A, Z = 8; Cs(0.4)K(0.6)(Et(4)N)(11)[(Mo(6)Br(6)S(2))(CN)(6)](3).16H(2)O, Pm-3m (No. 221), a = 17.1969(4) A, Z = 1; Cs(0.4)K(0.6)(Et(4)N)(11)[(Mo(6)Br(6)Se(2))(CN)(6)](3).16H(2)O, Pm-3m (No. 221), a = 17.235(5) A, Z = 1. 相似文献
36.
Naumov P. Jordanovska V. Boyanov B. Jovanovski G. 《Journal of Thermal Analysis and Calorimetry》2001,66(2):469-477
The complexes [M(HIm)4(H2O)2](sac)2 (M=Co, Ni) and [Cd(HIm)2(sac)2]2 with saccharin (sac) and imidazole (HIm) were synthesized and their thermal (TG, DTG and DTA) behaviour in the interval from
room temperature up to 1000°C in a static air atmosphere was investigated. Irrespectively of whether the deprotonated saccharinato
residues are present as ligands or ions or both as ligands and ions, the anhydrous complexes regularly decompose in two stages.
The thermal data of 16 saccharinato complexes (including the title compounds) were correlated with the respective structural
data. The general thermal stability order of the saccharinato complexes can be represented as: Pb(II)<Zn(II)<Co(II)Ni(II)<Cd(II)
(the stability of the Cu saccharinates depends on the particular compound) and is dictated by
several structural factors, e.g. metal ionic radii, participation of the water in the coordination sphere of the metal and
other structural characteristics.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
37.
The relation between the elastic shear constants and the dimensional Hume-Rothery factor is traced on the basis of the pseudopotential method for a number of bcc solid solutions AB. It is clarified that in the case of a substantial difference between the atomic volumes A and B, the constant c=(c11-c12)/2 takes on anomalously low values and even vanishes. The conclusion is hence made that the explanation of the 15% Hume-Rothery rule is possible from the aspect of stability of the crystalline lattice to shear. The presence of lattice distortion is not needed here in principle, as had been assumed earlier. It is shown that ordering of atoms according to the CsCl type can result in an abrupt increase in the value of c, i.e., in stabilizing the lattice of the initial disordered solid solution.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 97–102, March, 1980. 相似文献
38.
Mit"kina T. V. Gerasko O. A. Sokolov M. N. Naumov D. Yu. Fedin V. P. 《Russian Chemical Bulletin》2004,53(1):80-85
Slow evaporation of hydrochloric acid solutions of zirconium(iv) or hafnium(iv) oxochlorides and cucurbituril in air afforded compounds with composition [M4(OH)8(H2O)16]Cl8·(C36H36N24O12)·16H2O, where M = Zr (1) or Hf (2). According to the X-ray diffraction data, complexes 1 and 2 are isostructural. Their crystal structures can be described as packings of polymer chains consisting of alternating cucurbituril molecules and tetranuclear cations [M4(OH)8(H2O)16]8+ linked to each other via an extensive network of hydrogen bonds. Compound 2 is the first structurally characterized tetranuclear hafnium aqua complex. 相似文献
39.
V. A. Mamedov I. A. Litvinov F. G. Sibgatullina O. N. Kataeva I. A. Nuretdinov V. A. Naumov 《Chemistry of Heterocyclic Compounds》1994,30(2):169-172
Condensation of benzalaniline with N,N-dimethylamide of dichloroacetic acid under Darzens reaction conditions was used to obtain r-1, t-3-diphenyl-c-2-chloro-2-(NN-dimethylcarbamoyl)aziridine. The structure was established by x-ray diffraction analysis. Stabilization of the position of the substituents at the atoms of the aziridine ring by the hyperconjugation interaction of the unshared electron pair of the nitrogen atom with the antibonding orbital of the C-CI bond is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 189–192, February, 1994. Original article submitted November 30, 1993. 相似文献
40.
Internal rotation about the P?C bonds in the Cl2PCH=CH2 and Cl2PCH=CMe2 molecules is diseussed. It is shown that the cis (with eclipsed C=C bonds and lone electron pair of the phosphorus atom) and eclipsed conformers of the Cl2PCH=CH2 molecule are in equilibrium. The geometrical parameters and conformation compositions are refined. The content of the cis conformer is 40%. The Cl?P?C=C torsion angles are ±128.5° for the cis conformer and ?29.6 and ?132.6° for the eclipsed conformer. The Cl2PCH=CMe2 molecule occurs only in the cis form. For Cl2PCH=CMe2, the geometrical parameters are as follows: bond lengths C?H=1.124(11), C=C=1.322(8), P?C=1.789(3), and P?Cl=2.042(2) Å; bong angles (deg) C?P?Cl=99.1(4), Cl?P?Cl=99.6(6), C=C?CH3=120.1 and 125.7, and P?C=C=122.3(9); torsion angles Cl?P?C=C=±129.3(3). 相似文献