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91.
Hiromu Hayashi 《Catalysis Surveys from Japan》1999,3(1):43-52
Additive telluromolybdates, MoO3·2TeO2 and MIIO·TeO2·MoO3 (MIITeMoO6; MII = Co, Mn, Zn), converted ethyl lactate selectively to pyruvate in a vapor009666740h9v2/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">phase fixed009666740h9v2/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">bed flow system at 250013;300 °C. A synergy in activity was observed for binary TeO2013;MoO3, and crystalline 009666740h9v2/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">009666740h9v2/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">Te2MoO7 was suggested as the active species. The Rietveld analysis of powder XRD patterns of ternary CoTeMoO6 revealed the layer structure quite different from that of the reference 009666740h9v2/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">009666740h9v2/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">Te2MoO7, but tellurium was again located adjacent to molybdenum linked through lattice oxygen. 相似文献
92.
The main product of the reaction of 1-methylcyclobutanol with Pb(OAc)4 in benzene is 1-phenyl-4-pentanone; the use of Mn(OAc)3 in acetic acid gives a mixture of 2,9-decanedione and methyl propyl ketone; 1-(chloro-, bromo-, thiocyano-, or cyano)-4-pentanone is formed in the presence of the systems Pb(OAc)4-metal halide or Mn(OAc)3-metal halide.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2760013;2763, December, 1992. 相似文献
93.
H. Viernstein S. Reiter P. Wolschann 《Monatshefte für Chemie / Chemical Monthly》1994,125(6-7):681-689
Summary The solubility enhancement of triflumizole, a systemic fungicide, by 0u8/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin inclusion complexation was investigated by electron absorption spectroscopy. The respective association constant determined by different methods was estimated to 470±20M
013;1 in aqueous solution. A model for the host-guest complexation was deduced by molecular calculations.
Löslichkeitsverbesserung von Triflumizole durchHost-Guest-Complexierung mit 0u8/xhuge946.gif" alt="beta" align="MIDDLE" BORDER="0">-Cyclodextrin
Zusammenfassung Die Löslichkeitsverbesserung des systemischen Fungizids Triflumizole durch Komplexierung mit 0u8/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-Cyclodextrin wurde mittels Elektronenabsorptionsspektroskopie untersucht. Die entsprechende Stabilitätskonstante wurde durch verschiedene Methoden erfaßt und betrug im wäßrigen Medium 470±20M 013;1. Ein Model für denHost-Guest-Complex wurde durch Molekülrechnungen erstellt.相似文献
94.
A systematic extension of Ruedenberg's expansion formula is applied to evaluate two-electron integrals occurring in calculations on molecular structure. Minimum STO basis sets are used for all SCF-calculations within the framework of the MEDO-method (Multipole Expansion of Diatomic Overlap). The errors due to this approximation scheme are almost negligible compared to those introduced by the truncated basis set: LiH, Li2 and N2 are chosen as examples. 相似文献
95.
96.
Colin Thomson 《Theoretical chemistry accounts》1973,32(2):93-100
Non-empirical LCAO-MO-SCF calculations on SiF2 using two Gaussian basis sets are reported. The larger basis set gives a calculated geometry in good agreement with experiment. The effect on the energy and population analysis of optimization of the Si 3d exponent was investigated. 3d orbitals are found to be much less important in the bonding than in the isoelectronic molecule SO2. 相似文献
97.
Hidetake Sakuraba Yoshio Tananaka Fujio Toda 《Journal of inclusion phenomena and macrocyclic chemistry》1991,11(2):195-204
The asymmetric Michael addition of aromatic thiols to 2-cyclohexenone and maleic acid esters has been carried out by utilizing their crystalline cyclodextrin complexes suspended in water. The best chiral induction, 30% enantiomeric excess (ee), was achieved in combinations of 2-cyclohexenone and octyl maleate with the crystalline 0">-cyclodextrin complex of benzenethiol (method A) to afford (S)-3-phenylthiocyclohexanone and (S)-octyl-2-phenylthiosuccinate, respectively, whereas the reaction of benzenethiol with 2-cyclohexenone included in 0">-cyclodextrin (method B) inversely induced the chiral recognition to give the (R)-adduct with 4013;9% ee. 相似文献
98.
Krishna Gopal Dongol M. Cristina Melo e Silva Kouki Matsubara Taisuke Matsumoto Shuntaro Mataka Thies Thiemann 《无机化学与普通化学杂志》2003,629(6):945-947
The preparation of two η6‐estra‐1, 3, 5(10), 6‐tetraene tricarbonylchromium complexes 4 and 6 are described. In both cases only one stereoisomer can be isolated, in contrast to other estrane‐tricarbonylchromium complexes, where complexations are non‐stereoselective. X‐ray crystal structural analysis of 4 discloses that only the more sterically hindered β‐facial isomer is formed. It is assumed that the 6, 7‐olefinic moiety exerts a directive influence on the complexation. 相似文献
99.
The Wittig014;Horner reaction of CbzNHCH(CO2Me)P(O)(OMe)2 (1) with ArCHO (2) in the presence of Et3N as a base affords methyl (Z)-3-aryl-2-(carbobenzoxyamino)acrylates (3) with high degrees of diastereoselectivity (Z)/(E) > 100">0">1. One recrystallization of the crude product is sufficient to obtain isomerically and chemically pure (Z)-3.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2218-2220, November, 1995.The authors are grateful to the Dupont company (USA) for financing this study 相似文献
100.
It is shown that 2,2-difluoro-3-hydroxymethylbenzo-1,4-oxathianes are formed together with 3-trifluoromethylbenzo-1,4-oxathianes whenortho-(04/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-trifluoromethyl-04/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-chloroethylthio)phenols are boiled with excess aqueous alkali. The mechanism of the reaction is discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1457013;1459, August, 1994. 相似文献