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141.
142.
Peter W. Roesky 《无机化学与普通化学杂志》2003,629(11):1881-1894
The amido metal chemistry of the rare earth elements is a rapid developing area in coordination chemistry. Especially bulky mono and bidentate amido and amidinates have been introduced as ligands in rare earth chemistry. Due to these sterically demanding ligands, the coordination numbers of the rare earth elements are significantly reduced. This article focuses on two of these bulky ligand systems: bis(trimethylsilyl)amide and aminotroponiminates. The homoleptic bis(trimethylsilyl)amides of rare earth elements, [Ln{N(SiMe3)2}3], are well established compounds in synthetic chemistry. Therefore, this article reviews recent progress in the catalytic application of these compounds. In the second part of this research report, it is shown that N, N′‐disubstituted aminotroponiminates and mono bridged bisaminotroponiminates can be used as cyclopentadienyl alternatives. Achiral and chiral aminotroponiminates have been used. The structural properties, reactivities as well as the catalytic and synthetic applications of the aminotroponiminates complexes will be outlined in this article. 相似文献
143.
Syntheses and Structures of functional substituted Ferrocenes Substituted ferrocenes have been prepared using carbonic acid chloride of ferrocene. New pathways have been found reacting the acid chloride with sodium hexamethyldisilazane and tris(trimethylsilyl)phosphane, respectively. The compounds FecC(OSiMe3)N(SiMe3) (Fec = C5H5FeC5H4) 1 and FecC(OSiMe3)P(SiMe3) 2 have been obtained and characterized by X-ray single crystal structure analysis. Experiments for the preparation of FecCP 3 are reported. 相似文献
144.
The eight-membered chloro hafnium siloxane complex [Cl2HfOtBu2SiO(THF)2]2 2 has been prepared by the reaction of hafnium tetrachloride and tBu2Si(OSnMe3)2 1 . The X-ray single crystal structure of [Cl2HfOtBu2SiO(THF)2]2 is reported. The reaction of 2 with Me3SnF in a molar ratio of 1:4 leads to the corresponding fluoro complex 3 . The reaction of [(C5Me5)HfCl3] with the lithiated silanediol tBu2Si(OLi)2 yields [(C5Me5)ClHfOtBu2SiO]2 4 . 相似文献
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147.
Vibration spectra and force constants of the series O2PF — S2PF — S2P(CH3). The vibrational spectra of OSPF, S2PF, S2PF(CH3) and S2P(CN) are reported and discussed with O2PF and S2P(CH3). On the basis of a simplified valence-force-field the force constants are calculated and the bonding relations are discussed. In the ions, f PF is lower than in corresponding molecules. The ionic charge is distributed over nearly all atoms of the ions. 相似文献
148.
Syntheses of the Anion S3N3O2?, a Stable Six-membered Sulfur-Nitrogen Ring with an 8π-Electron Skeleton The dark blue-violet cyclotrithiazene-dioxide anion S3N3O2?has been synthesized on different pathways: 1. reaction of S4N4O2 with alkali azides, 2. metathesis of (CH3)3ES3N3O2 (E = Si, Sn) with CsF, 3. addition of S4N4O2 and alkali bis(trimethylsilyl)-amides followed by cation exchange with tetraphenylarsonium chloride, and 4. reaction of S4N4O2 with trimethylsilyliminotriphenylphosphorane in a molar ratio of 1:1. Excess iminophosphorane leads to the formation of a covalent 1.5-disubstituted S4N4 derivative. Reaction mechanisms will be discussed and structures of trithiatriazine-anions will be compared. 相似文献
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150.
Stender M Eichler BE Hardman NJ Power PP Prust J Noltemeyer M Roesky HW 《Inorganic chemistry》2001,40(12):2794-2799
A series of group 13 metal complexes featuring the beta-diketiminate ligand [[(C(6)H(3)-2,6-i-Pr(2))NC(Me)](2)CH](-) (i.e., [Dipp(2)nacnac](-), Dipp = C(6)H(3)-2,6-i-Pr(2)) have been prepared and spectroscopically and structurally characterized. The chloride derivatives Dipp(2)nacnacMCl(2) (M = Al (3), Ga (5), In (8)) were isolated in good yield by the reaction of 1 equiv of Dipp(2)nacnacLi.Et(2)O (2) and the respective metal halides. The iodide derivatives Dipp(2)nacnacMI(2) (M = Al (4), Ga (6), In (9)), which are useful for reduction to afford M(I) species, were made by a variety of routes. Thus, 4 was obtained by treatment of the previously reported Dipp(2)nacnacAlMe(2) with I(2), whereas the gallium analogue 6 was obtained as a product of the reaction of "GaI" with Dipp(2)nacnacLi.Et(2)O, and 9 was obtained by direct reaction of InI(3) and the lithium salt. The methyl derivatives Dipp(2)nacnacMMe(2) (M = Ga (7), In (10)), which are analogous to the previously reported Dipp(2)nacnacAlMe(2), were synthesized by the reaction of GaMe(3) with Dipp(2)nacnacH (1) or by reaction of the indium chloride derivative 8 with 2 equiv of MeMgBr in diethyl ether. The compounds 3-10 exist as colorless, air- and moisture-sensitive crystalline solids. Their X-ray crystal structures feature nearly planar C(3)N(2) arrays in the Dipp(2)nacnac ligand backbone with short C-C and C-N distances that are consistent with a delocalized structure. However, there are large dihedral angles between the C(3)N(2) plane and the N(2)M metal coordination plane which have been attributed mainly to steric effects. The relatively short M-N distances are consistent with the coordination numbers of the metals and the normal/dative character of the nitrogen ligands. The compounds were also characterized by (1)H and (13)C NMR spectroscopy. (1)H NMR data for 7 revealed equivalent methyl groups whereas the spectrum of 10 displayed two In-Me signals which indicated that ring wagging was slow on the (1)H NMR time scale. 相似文献