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91.
T. L. Che Q. C. Gao W. P. Zhang Z. X. Nan H. X. Li Y. G. Cai J. S. Zhao 《Russian Journal of Coordination Chemistry》2009,35(10):723-730
Coordination polymers, [Sm2(Pzdc)3(H2O)]
x
· 2xH2O (I) and [Nd2(Pzdc)3(H2O)]
x
· 2xH2O (II), were obtained by hydrothermal reactions with 2,3-pyrazinedicarboxylic acid (H2Pzdc) and the salts nitrates, and characterized by single crystal X-ray structure, thermogravimetric analysis, element analysis
and infrared spectroscopy. The X-ray crystal diffraction data indicates that two complexes crystal in a monoclinic system
with the space group P21/c, of the three dimensional framework. The Pzdc ligand in the complexes I and II adopts tetradentate, hexadentate, and heptadentate
bridging modes. The influences of coordination modes of the Pzdc ligand on the superstructural diversity is discussed. The
photoluminescent data suggest that the ligands act as efficient “antennas” sensitizing the luminescence of the Sm3+ ion. Complex I exhibits strong fluorescent emission bands in the solid state at room temperature. 相似文献
92.
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96.
The principle of step-scan Fourier transform infrared (FTIR) spectroscopy is introduced. Double modulation step-scan FTIR technique is used to obtain the quantum cascade laser's stacked emission spectra in the time domain. Optical property and thermal accumulation of devices due to large drive current are analyzed. 相似文献
97.
Xiaoling Huang Yebang Tan Yuexia Wang Hui Yang Jie Cao Yuju Che 《Journal of polymer science. Part A, Polymer chemistry》2008,46(18):5999-6008
The novel copolymers of acrylamide (AM) with complex pseudorotaxane monomer (BAMACB) of butyl ammonium methacrylate (BAMA) and cucurbit[6]uril (CB[6]) were prepared via free‐radical polymerization in aqueous solution. The copolymers containing pseudorotaxane (PAM/BAMACB) were characterized by 1H‐NMR, FTIR, elemental analysis, TGA, and DSC. The glass transition temperature (Tg) of the copolymer PAM/BAMACB are higher than that of the copolymer of acrylamide and butyl ammonium methacrylate (PAM/BAMA) because of the enhanced rigidity and the bulky steric hindrance of BAMACB side chain in PAM/BAMACB. The molecular weights of copolymer PAM/BAMACB were obtained via static light scattering. The hydrodynamic radii of coils or aggregates were investigated by dynamic light scattering. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5999–6008, 2008 相似文献
98.
99.
<正>Two new homoisoflavanones were isolated from the rhizomes of Polygonatum odoratum(Mill.) Druce and their structures were elucidated as(3R)-5,7-dihydroxy-8-methoxy-3-(4-methoxybenzyl)-6-methylchrom-an-4-one(1) and(3R)-5,7,8-trihydroxy-3-(4- hydroxybenzyl)-6-methylchroman-4-one(2),on the basis of spectral analysis. 相似文献
100.
Ming‐Zhong Wang Cong‐Ying Zhou Man‐Kin Wong Dr. Chi‐Ming Che Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(19):5723-5735
Ruthenium porphyrins (particularly [Ru(2,6‐Cl2tpp)CO]; tpp=tetraphenylporphinato) and RuCl3 can act as oxidation and/or Lewis acid catalysts for direct C‐3 alkylation of indoles, giving the desired products in high yields (up to 82 % based on 60–95 % substrate conversions). These ruthenium compounds catalyze oxidative coupling reactions of a wide variety of anilines and indoles bearing electron‐withdrawing or electron‐donating substituents with high regioselectivity when using tBuOOH as an oxidant, resulting in the alkylation of N‐arylindoles to 3‐{[(N‐aryl‐N‐alkyl)amino]methyl}indoles (yield: up to 82 %, conversion: up to 95 %) and the alkylation of N‐alkyl or N‐H indoles to 3‐[p‐(dialkylamino)benzyl]indoles (yield: up to 73 %, conversion: up to 92 %). A tentative reaction mechanism involving two pathways is proposed: an iminium ion intermediate may be generated by oxidation of an sp3 C? H bond of the alkylated aniline by an oxoruthenium species; this iminium ion could then either be trapped by an N‐arylindole (pathway A) or converted to formaldehyde, allowing a subsequent three‐component coupling reaction of the in situ generated formaldehyde with an N‐alkylindole and an aniline in the presence of a Lewis acid catalyst (pathway B). The results of deuterium‐labeling experiments are consistent with the alkylation of N‐alkylindoles via pathway B. The relative reaction rates of [Ru(2,6‐Cl2tpp)CO]‐catalyzed oxidative coupling reactions of 4‐X‐substituted N,N‐dimethylanilines with N‐phenylindole (using tBuOOH as oxidant), determined through competition experiments, correlate linearly with the substituent constants σ (R2=0.989), giving a ρ value of ?1.09. This ρ value and the magnitudes of the intra‐ and intermolecular deuterium isotope effects (kH/kD) suggest that electron transfer most likely occurs during the initial stage of the oxidation of 4‐X‐substituted N,N‐dimethylanilines. Ruthenium‐catalyzed three‐component reaction of N‐alkyl/N‐H indoles, paraformaldehyde, and anilines gave 3‐[p‐(dialkylamino)benzyl]indoles in up to 82 % yield (conversion: up to 95 %). 相似文献