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111.
In this paper, we established travelling wave solutions for some (2 + 1)-dimensional nonlinear evolution equations. The first integral method was used to construct travelling wave solutions of nonlinear evolution equations. The travelling wave solutions are expressed by the hyperbolic functions, the trigonometric functions and the rational functions. The first integral method presents a wider applicability for handling nonlinear wave equations.  相似文献   
112.
The in situ prepared three component system Pd(OAc)2, 1,3‐dialkylbenzimidazolium halides ( 1a‐e ) and t‐BuOK catalyses quantitatively the Suzuki cross‐coupling of deactivated aryl chloride substrates. 1,3‐Dialkylbenzimidazolium salts ( 1a‐e ) were characterized by conventional spectroscopic methods and elemental analyses.  相似文献   
113.
Selective O-benzylation of primary hydroxy compounds has been achieved in the presence of bis[acetylacetonato]copper with benzyl chloride. We showed that bis[acetylacetonato]copper was very efficient in promoting the benzylation of primary aliphatic alcohols versus secondary aliphatic alcohols and phenolic hydroxy groups selectively.  相似文献   
114.
A series of Ni(II), Pd(II) and Cu(II) metal complexes of highly functionalized aroylaminocarbo-N-thioyl pyrrolidines were prepared and characterized by microanalysis, spectroscopic methods, magnetic susceptibility measurements and single crystal X-ray diffraction studies. The antifungal activity of the metal complexes against the yeast Saccharomyces cerevisae and against the fungus Penicillium digitatum was studied.  相似文献   
115.
Complexes of luteinizing hormone releasing hormone (LHRH) with divalent metal ions (Ni, Zn, Cu) have been studied by matrix-assisted laser desorption ionization (MALDI) and Fourier transform mass spectrometry. LHRH-metal complexes were detected in high abundance for all three metals from synthesized samples, particularly in negative ion mode. The mixture of the apopeptide with the metal salts yielded in most cases a very minor signal of metal-complex ions. As opposed to Ni and Zn, copper complex ions were mostly observed as Cu(I) adducts. This can be partly attributed to plume reactions of Cu(I) with the apopeptide. the Cu(II) complexes appeared only for the synthetic complex. We show how to distinguish between the contribution to the overall signal from desorbed complexes and from Cu(I) complexes formed in the MALDI plume.  相似文献   
116.
In this study, polyindole (PIN)/TiO2 nanocomposites were synthesized with and without the presence of sodium dodecylsulfate, anionic surfactant, with two different PIN contents. The synthesized materials were subjected to various characterizations namely: particle size, apparent density, conductivity, dielectric constants, magnetic susceptibility, elemental analysis, Fourier transform infrared spectroscopy spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Characterization results revealed the successful preparations of PIN/TiO2 hybrid nanocomposites. Electrokinetic properties of all the materials were determined by zeta (ζ)-potential measurements in aqueous and nonqueous media. Effects of pH, temperature, presence of various electrolytes, and surfactants on electrokinetic properties of the materials were examined.  相似文献   
117.
A new reactive capillary monolith as an alternative to the commonly employed glycidyl methacrylate-based stationary phases in capillary electrochromatography (CEC) applications was synthesized and post-functionalized with charge-bearing groups. For this purpose, a hydrophilic capillary monolith with reactive 3-chloro-2-hydroxypropyl moiety was first obtained by the copolymerization of a new methacrylate-based monomer, 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl), with a methacrylic crosslinking agent, ethylene glycol dimethacrylate (EDMA). The presence of 3-chloro-2-hydroxypropyl functionality in poly(HPMA-Cl-co-EDMA) monolith allowed the synthesis of monoliths carrying strongly ionizable anionic, cationic or neutral groups such as sulfonic acid, quaternary ammonium or octadecyl, respectively, via simple and single-stage reactions. In the present study, a reactive poly(HPMA-Cl-co-EDMA) capillary monolith was functionalized with sodium bisulfite (NaHSO3) to have a strongly ionizable sulfonic acid group on the monolith. The resulting monolith providing cathodic electroosmotic flow in CEC was successfully used for the separation of phenol derivatives. The theoretical plate numbers up to 63,000 plates/column were achieved. The results showed that a new promising, reactive support that could be functionalized with different chromatographic ligands for different chromatographic applications was obtained in the study.  相似文献   
118.
Abstract

In this study, phytochemical composition of Arnebia densiflora (AD) was determined and cytotoxic effects of the n-hexane extract and compounds isolated from this species on various cell lines were investigated. By means of serial chromatographic studies, 6 naphthoquinone derivatives were yielded, which are isovalerylalkannin, α-methyl-n-butyl alkannin, acetylalkannin, β-acetoxy isovalerylalkannin, alkannin and a new compound: 4-hydroxy 4-methyl valeryl alkannin. Structures of the isolated compounds were elucidated using UV, IR, 1D-2D NMR, MS and CD methods. Cytotoxic effects of the extract and isolated alkannins were investigated on L929, HeLa, HEp-2 cells. AD and the isolated compounds demonstrated moderate to strong cytotoxic effects (IC50 range: 4.92-172.35?µg/ml). The results of DNA fragmentation and caspase-3 activity studies on HeLa cells exhibited that AD and the naphthoquinones isolated from it caused cytotoxicity through induction of apoptosis.

  相似文献   
119.
120.
In the title compound, [CuCl2(C11H15N3O2)], the CuII ion is five‐coordinated in a strongly distorted trigonal–bipyramidal arrangement, with the two methyl­oxime N atoms located in the apical positions, and the pyridine N and the Cl atoms located in the basal plane. The two axial Cu—N distances are almost equal (mean 2.098 Å) and are substantially longer than the equatorial Cu—N bond [1.9757 (15) Å]. It is observed that the N(oxime)—M—N(pyridine) bond angle for five‐membered chelate rings of 2,6‐diacetyl­pyridine dioxime complexes is inversely related to the magnitude of the M—N(pyridine) bond. The structure is stabilized by intra‐ and inter­molecular C—H⋯Cl hydrogen bonds which involve the methyl H atoms, except for one of the two acetyl­methyl groups.  相似文献   
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