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141.
F. Farchioni P. Hofmann K. Jansen I. Montvay G. Münster E.E. Scholz L. Scorzato A. Shindler N. Ukita C. Urbach U. Wenger I. Wetzorke 《The European Physical Journal C - Particles and Fields》2006,47(2):453-472
Discretisation errors in two-flavour lattice QCD with Wilson quarks and DBW2 gauge action are investigated by comparing numerical
simulation data at two values of the bare gauge coupling. Both non-zero- and zero-twisted-mass values are considered. The
results, including also data from simulations using the Wilson plaquette gauge action, are compared to next-to-leading order
chiral perturbation theory formulas. 相似文献
142.
In this paper the main focus is on a stability concept for solutions of a linear complementarity problem. A solution of such
a problem is robust if it is stable against slight perturbations of the data of the problem. Relations are investigated between
the robustness, the nondegenerateness and the isolatedness of solutions. It turns out that an isolated nondegenerate solution
is robust and also that a robust nondegenerate solution is isolated. Since the class of linear complementarity problems with
only robust solutions or only nondegenerate solutions is not an open set, attention is paid to Garcia's classG
n
of linear complementarity problems. The nondegenerate problems inG
n
form an open set. 相似文献
143.
Johanna Méndez Arias Anelize de Oliveira Moraes Luiz Felipe Amarante Modesto Aline Machado de Castro Nei Pereira Jr 《Applied biochemistry and biotechnology》2017,181(2):593-603
Poly(ethylene glycol) (PEG 4000) and bovine serum albumin (BSA) were investigated with the purpose of evaluating their influence on enzymatic hydrolysis of sugarcane bagasse. Effects of these supplements were assayed for different enzymatic cocktails (Trichoderma harzianum and Penicillium funiculosum) that acted on lignocellulosic material submitted to different pretreatment methods with varying solid (25 and 100 g/L) and protein (7.5 and 20 mg/g cellulose) loadings. The highest levels of glucose release were achieved using partially delignified cellulignin as substrate, along with the T. harzianum cocktail: increases of 14 and 18 % for 25 g/L solid loadings and of 33 and 43 % for 100 g/L solid loadings were reached for BSA and PEG supplementation, respectively. Addition of these supplements could maintain hydrolysis yield even for higher solid loadings, but for higher enzymatic cocktail protein loadings, increases in glucose release were not observed. Results indicate that synergism might occur among these additives and cellulase and xylanases. The use of these supplements, besides depending on factors such as pretreatment method of sugarcane bagasse, enzymatic cocktails composition, and solid and protein loadings, may not always lead to positive effects on the hydrolysis of lignocellulosic material, making it necessary further statistical studies, according to process conditions. 相似文献
144.
Désirée L. Röhlen Johanna Pilas Michael J. Schöning Thorsten Selmer 《Applied biochemistry and biotechnology》2017,183(2):566-581
Three amperometric biosensors have been developed for the detection of l-malic acid, fumaric acid, and l -aspartic acid, all based on the combination of a malate-specific dehydrogenase (MDH, EC 1.1.1.37) and diaphorase (DIA, EC 1.8.1.4). The stepwise expansion of the malate platform with the enzymes fumarate hydratase (FH, EC 4.2.1.2) and aspartate ammonia-lyase (ASPA, EC 4.3.1.1) resulted in multi-enzyme reaction cascades and, thus, augmentation of the substrate spectrum of the sensors. Electrochemical measurements were carried out in presence of the cofactor β-nicotinamide adenine dinucleotide (NAD+) and the redox mediator hexacyanoferrate (III) (HCFIII). The amperometric detection is mediated by oxidation of hexacyanoferrate (II) (HCFII) at an applied potential of + 0.3 V vs. Ag/AgCl. For each biosensor, optimum working conditions were defined by adjustment of cofactor concentrations, buffer pH, and immobilization procedure. Under these improved conditions, amperometric responses were linear up to 3.0 mM for l-malate and fumarate, respectively, with a corresponding sensitivity of 0.7 μA mM?1 (l-malate biosensor) and 0.4 μA mM?1 (fumarate biosensor). The l-aspartate detection system displayed a linear range of 1.0–10.0 mM with a sensitivity of 0.09 μA mM?1. The sensor characteristics suggest that the developed platform provides a promising method for the detection and differentiation of the three substrates. 相似文献
145.
Franziska Gruber Martin Schulz‐Dobrick Dr. Martin Jansen Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(5):1464-1469
Crystallization of [Ag14(C?CtBu)12Cl][BF4] and different polyoxometalates in organic solvents yields a series of new intercluster compounds: [Ag14(C?CtBu)12Cl(CH3CN)]2[W6O19] ( 1 ), (nBu4N)[Ag14(C?CtBu)12Cl(CH3CN)]2[PW12O40] ( 2 ), and [Ag14(C?CtBu)12Cl]2[Ag14(C?CtBu)12Cl(CH3CN)]2[SiMo12O40] ( 3 ). Applying the same technique to a system starting from polymeric {[Ag3(C?CtBu)2][BF4]?0.6 H2O}n and the polyoxometalate (nBu4N)2[W6O19] results in the formation of [Ag14(C?CtBu)12(CH3CN)2][W6O19] ( 4 ). Here, the Ag14 cluster is generated from polymeric {[Ag3(C?CtBu)2][BF4]?0.6 H2O}n during crystallization. In a similar way, [Ag15(C?CtBu)12(CH3CN)5][PW12O40] ( 5 ) has been obtained from {[Ag3(C?CtBu)2][BF4]?0.6 H2O}n and (nBu4N)3[PW12O40]. The use of charged building blocks was intentional, because at these conditions the contribution of long‐range Coulomb interactions would benefit most from full periodicity of the intercluster compound, thus favoring formation of well‐crystalline materials. The latter has been achieved, indeed. However, as a most conspicuous feature, equally charged species aggregate, which demonstrates that the short‐range interactions between the “surfaces” of the clusters represent the more powerful structure direction forces than the long‐range Coulomb bonding. This observation is of significant importance for understanding the mechanisms underlying self‐organization of monodisperse and structurally well‐defined particles of nanometer size. 相似文献
146.
Several fluorine containing polycyclic aromatic hydrocarbons with exact carbon atom topology of the C60 fullerene have been synthesized. Different numbers of fluorine atoms were introduced in the key positions, as needed for an efficient intramolecular condensation to the fullerene molecule. The polycyclic aromatic compounds obtained represent attractive precursors for rational, high-yield fullerene synthesis by flash vacuum pyrolysis. 相似文献
147.
The correlation energy in the direct random phase approximation (dRPA) can be written, among other possibilities, either in terms of the interaction strength averaged correlation density matrix, or in terms of the coupled cluster doubles amplitudes obtained in the direct ring approximation (drCCD). Although the corresponding dRPA correlation density matrix on the one hand, and the drCCD amplitude matrix on the other hand, differ significantly, they yield identical energies. Similarly, the analogous RPA and rCCD correlation energies calculated from antisymmetrized two-electron integrals are identical to each other despite very different underlying working equations. In the present communication, a direct correspondence between amplitudes and densities is established and investigated with perturbation theory arguments. Our analysis also sheds some light on the properties of recently proposed RPA/rCCD variants which use antisymmetrized integrals in part of the equations and nonantisymmetrized integrals in others. 相似文献
148.
Johanna H. Kasser Christian G. Hartinger Alexey A. Nazarov Vladimir B. Arion Bernhard K. Keppler 《Journal of organometallic chemistry》2010,695(6):875-2512
Ru(II)-η6-p-cymene compounds bearing pyrone-derived ligands, which were obtained by Mannich reaction with piperidine and related analogues, have been synthesized. The compounds were characterized by NMR spectroscopy, mass spectrometry, thermogravimetric analysis and in the case of 2-(2,6-dimethyl-morpholin-4-ylmethyl)-3-hydroxy-6-hydroxymethyl-pyran-4-one by X-ray diffraction analysis. The chlorido complexes are prone to aquation in aqueous solution which results in the formation of dimers. Dimer formation can be inhibited by in situ replacement of the chlorido ligand by imidazole yielding compounds which are significantly more stable in water, as demonstrated by 1H NMR spectroscopy. 相似文献
149.
Alaerts G Dejaegher B Smeyers-Verbeke J Vander Heyden Y 《Combinatorial chemistry & high throughput screening》2010,13(10):900-922
The use of chromatographic fingerprints from herbal products where the whole chromatographic profile is applied to evaluate the quality of the investigated product. In this paper, recent developments in the set-up and data analysis of chromatographic fingerprints for herbal products are discussed. First different set-ups for fingerprint development are reviewed. Prior to fingerprint development, a suitable sample preparation, e.g. extraction, should be considered. In a second instance, this review focuses on the data analysis with regards to the different applications of fingerprints. Usually, chemometric data pretreatment is necessary. This is discussed first, followed by a short overview of the data handling techniques used in the two main application areas of herbal fingerprints, i.e. quality assurance and classification or calibration. The quality assurance, which involves the identification and quality control of the herbal products, is reviewed, followed by the use of fingerprints in classification or modelling. The different application areas are illustrated and discussed with several case studies. 相似文献
150.