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61.
62.
Akio Fukuzawa Hideki Matsue Mitsuhiko Ikura Tadashi Masamune 《Tetrahedron letters》1985,26(45):5539-5542
The structure of two new nortriterpenes, glycinoeclepins B and C, isolated from the aqueous extracts of roots of kidney bean and related structurally to glycinoeclepin A, a natural hatching stimulus for the soybean cyst nematode, has been elucidated to be formulas 2 and 3, respectively. 相似文献
63.
64.
(1,4,7,10-Tetraazacyclododecane) [diamine or (S)-alanine]-cobalt(III) complexes [diamine = ethylenediamine, 2-(aminomethyl)pyridine, (R)-1,2-propanediamine, (R,R)-1,2-diaminocyclohexane, trimethylenediamine and 2-methyl-1,3-diaminopropane] are prepared and characterized spectroscopically. The ligand field transitions occur at lower energies than those of the corresponding tetraamine analogues. Severe distortions caused by the too small size of the cyclic ligand are one of the origins. The distortions also exert influence upon circular dichroism spectra. 相似文献
65.
Yui T Tsuchino T Itoh T Ogawa M Fukushima Y Takagi K 《Langmuir : the ACS journal of surfaces and colloids》2005,21(7):2644-2646
Composite films of a meso-(tetramethylpyridinium)porphyrin (TMPyP) hybrid incorporated in mesoporous silica (MPS) and cast on a methyl viologen (MV2+)/titania nanosheet hybrid were synthesized and a light-induced charge separation between the two could be observed. These composite thin films were able to initiate a one-electron reduction of the MV2+ ions accompanied by the simultaneous decomposition of the TMPyP organic dye within the mesoporous silica channels. 相似文献
66.
A large macrocyclic compound with six para-phenylene rings and six amide moieties, which are alternately secondary and tertiary, was synthesized. In a stepwise synthesis, the final cyclization step was successful because a combination of three tertiary amides, which prefer a cis conformation, and two linear secondary amides would arrange both amino and carboxyl ends close to each other, while various sizes of macrocyclic compounds including the target cyclic trimer were generated in one-pot synthesis where three secondary amide bonds were formed. 相似文献
67.
The preparation of the angular and linear isomers of benzo-fused 1,4-dimethyl-2(1H)-quinolinones 3a–5a and their spectral data including 13C-nmr data are reported. Structural difference among 3a–5a is confirmed from the proximity effect in 1H- and 13C-nmr data and from the uv spectral pattern. 相似文献
68.
Takeshi Tsumuraya Scott A. Batcheller Satoru Masamune 《Angewandte Chemie (International ed. in English)》1991,30(8):902-930
The organometallic chemistry of the Group 14 elements E = Si, Ge, Sn in the 1980's is highlighted by the successful construction and characterization of three systems previously thought to be too reactive to exists: (1) three-membered ring compounds including cyclotrisilane, cyclotrigermane, and cyclotristannane, (2) molecules containing E? E double bonds including disilene, digermene, and distannene, and (3) strained polycycles containing a skeleton of Group 14 elements, such as bicyclo[1.1.0]tetrasilane, hexagemaprismane, and octasilacubane. The majority of these numerous compounds now available are fully substituted with bulky ligands to suppress the reactivity intrinsic to the systems. These compounds permit examinations of (1) the variation of physical and chemical properties of a system with these elements and also with the ligands and (2) how two systems are interrelated thermally and photochemically with the intermediacy of the divalent (carbene-like) species. Theoretical calculations on virtually all of the parent compounds discussed in this review are evaluated alongside the experimental results. Some polycycles may constitute a stepping-stone on the way to compounds with a triple bond. 相似文献
69.
Mitsuo Takasugi Shigemitsu Nagao Tadashi Masamune Akira Shirata Kokichi Takahashi 《Tetrahedron letters》1979,20(48):4675-4678
The structures and antifungal activity of four new mulberry phytoalexins, designated as moracins E, F, G, and H, are described. 相似文献
70.
Kanazawa H Okada A Igarashi E Higaki M Miyabe T Sano T Nishimura R 《Journal of chromatography. A》2004,1031(1-2):213-218
This study demonstrated the analysis of midazolam and its metabolites by liquid chromatography-mass spectrometry (LC-MS) with a sonic spray ionization (SSI) interface. The analytical column was a YMC-Pak Pro C18 (50 mm x 2.0 mm i.d.) using 10 mM ammonium acetate (pH 4.8)-methanol (1:1) at a flow rate of 0.2 ml min(-1). The drift voltage was 100 V. The sampling aperture was heated at 110 degrees C and the shield temperature was 230 degrees C. The lower limits for the detection of midazolam and 1'-hydroxymidazolam were 26.3 and 112.76 pg injected, respectively. The calibration curves for midazolam and 1'-hydroxymidazolam were linear in the range of 0.1-5 microg ml(-1). Within-day relative standard deviations was less than 7%. The method was applied to the determination of midazolam in monkey plasma, and the analysis of midazolam and its metabolites in an in vitro study with recombinant cytochrome P450 (CYP) 3A4. This method is sufficiently sensitive and useful to elucidate the kinetics of midazolam metabolite formation. We also investigated the effect of propofol on the metabolism of midazolam using recombinant CYP3A4. Propofol competitively inhibited the metabolism of midazolam to 1'-hydroxymidazolam by CYP3A4. 相似文献