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1.
M. Randić J. Zupan M. Novič B.D. Gute S.C. Basak 《SAR and QSAR in environmental research》2013,24(7-8):689-703
Previous studies on mathematical characterization of proteomics maps by sets of map invariants were based on the construction of a set of distance-related matrices obtained by matrix multiplication of a single matrix by itself. Here we consider an alternative characterization of proteomics maps based on a set of matrices characterizing local features of an embedded zigzag curve over the map. It is shown that novel invariants can well characterize proteomics maps. Advantages of the novel approach are discussed. 相似文献
2.
Suely L. Galdino Maria C. A. Lima Alexandre J. S. Góes Ivan R. Pitta Cuong Luu-Duc 《光谱学快报》2013,46(7-8):1013-1021
In the present investigation, a study of the electron impact mass spectrometry data is reported for seven compounds of a series of some 3-(4-chlorobenzyl)-5-benzylidene-imidazolidine-2, 4-diones and 3-(4-fluoro or chlorobenzyl)-5-benzylidene-thiazolidine-2, 4-diones previously synthesized. 相似文献
3.
David M. Rackham 《光谱学快报》2013,46(8):517-520
Paper 16 in this series1, 2, 3 was concerned with the equilibrium binding constants (K) of the shift reagent Europium tris (2, 2, 6, 6-tetramethylheptane-3, 5-dionate), Eu(thd)3, with primary, secondary and tertiary amines. One nitrogen heterocycle, pyridine, and two of its derivatives (see Table) were included. In the present paper we describe the binding constants for a further 9 nitrogen containing heterocycles and relate these to basicity and steric effects. 相似文献
4.
《Discrete Mathematics》2019,342(10):2770-2782
“Which graphs are determined by their spectrum (DS for short)?” is a fundamental question in spectral graph theory. It is generally very hard to show a given graph to be DS and few results about DS graphs are known in literature. In this paper, we consider the above problem in the context of the generalized -spectrum. A graph is said to be determined by the generalized -spectrum (DGQS for short) if, for any graph , and have the same -spectrum and so do their complements imply that is isomorphic to . We give a simple arithmetic condition for a graph being DGQS. More precisely, let be a graph with adjacency matrix and degree diagonal matrix . Let be the signless Laplacian matrix of , and ( is the all-ones vector) be the -walk matrix. We show that if (which is always an integer) is odd and square-free, then is DGQS. 相似文献
5.
6.
Electron impact mass spectral fragmentation of certain esters and amides derived from 4-hydroxy-2H-1,2-benzothiazine-3-carboxylic acid 1,1-dioxide is described. Common ions to both series may be observed, as well as others allowing them to be differentiated. The method is promissory for identification and analysis of these compounds. 相似文献
7.
Synthesis of ethylene/vinyl ester copolymers with pendent linear branches via ring‐opening metathesis polymerization of fatty acid‐derived cyclooctenes 下载免费PDF全文
Yuchen Feng Suyun Jie Bo‐Geng Li 《Journal of polymer science. Part A, Polymer chemistry》2017,55(13):2211-2220
Fatty acid‐derived cyclooctenes, including n‐hexanoic acid ( M1 ), n‐octanoic acid ( M2 ), lauric acid ( M3 ), and palmitic acid ( M4 ), were prepared as monomers and polymerized by ring‐opening metathesis polymerization (ROMP) using Grubbs second‐generation catalyst ( G2 ). In all the cases, the regio‐irregular unsaturated polymers with pendent linear branches were obtained, which could be saturated by chemical hydrogenation with TSH/TPA in high conversion, yielding ethylene/vinyl ester copolymers with pendent linear branches on precisely every eighth backbone carbon. Both unsaturated and saturated polymers were amorphous, and their structures were characterized by FTIR, 1H and 13C NMR spectra, and elemental analysis. Differential scanning calorimetry (DSC) and thermo‐gravimetric analysis (TGA) were used to study their thermal properties. The chain length of branches greatly affected the thermal properties of polymers. After hydrogenation, the thermal degradation stability of polymers was relatively improved. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2211–2220 相似文献
8.
V. L. Broude 《Molecular Crystals and Liquid Crystals》2013,570(1):9-21
Mechanistic aspects of the two step Durham route to polyacetylene are discussed. It is shown that a catalyst based on MoCl5 gives a higher proportion of cis vinylenes in both precursor polymer and nascent polyacetylene than does a WC16 based system. 相似文献
9.
M. H. Elnagdi M. A. Selim F. M. Abd El Latif S. Samia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1175-1182
5-Acetyl-2-cyanomethyl-4-methylthiazole, 2-aminothiazole, and 5-N-benzoylamino-1,3,4-thiadiazole-2-yl-acetonitrile react with acetone, and malononitrile derivatives in the presence of sulfur to yield the corresponding thiophene derivatives. Also, 4-furylmethylene-2-phenyl-2-oxazolin-5-ones react with thiophenol, and/or thionaphthol to give the thiolester derivatives in one-pot synthesis. The structures of the products were based on IR, 1 H NMR, and elemental analysis. 相似文献
10.
A. Abouimrane K. Sbai K. El Kababi A. Lahmidi A. Atibi Serge Vilminot 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):605-619
The dehydration of ZnRb 4 (P 3 O 9 ) 2 ·;6H 2 O was investigated, between 25 and 600°;C, by TG-DTA, X-ray diffraction, IR. It leads, between 300 and 500°;C, to a mixture of long chain polyphosphates RbPO 3 and ZnRb 2 (PO 3 ) 4 which stays stable until its melting point. The IR (1400-30 cm m 1 ) and Raman spectra (1400-100 cm m 1 ) of ZnRb 4 (P 3 O 9 ) 2 ·;6H 2 O are reported and assignments of fundamental modes proposed and compared with theoretical results obtained via the MNDO method for P 3 O 9 ring with C s symmetry. (La déshydratation, sous pression atmosphérique, du cyclotriphosphate ZnRb 4 (P 3 O 9 ) 2 ·;6H 2 O, a ét´;e effectuée, entre 25 and 600°;C, par spectrométrie IR, diffraction des rayons X, ATG et ATD. Elle conduit, entre 300 and 500°;C, au mélange de polyphosphates RbPO 3 et ZnRb 2 (PO 3 ) 4 qui reste stable jusqu'à la fusion. Les spectres vibrationnels IR (1400-30 cm m 1 ) et Raman (1400-100 cm m 1 ) du sel étudié ont été interprétés dans le domaine des vibrations de valence et de déformation du cycle P 3 O 9 et comparés avec les résultats des calculs théoriques par la méthode MNDO pour un cycle isolé de symétrie C s .) 相似文献