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81.
Pál Perjési Gábor Maász Renáta Reisch András Benk? 《Monatshefte für Chemie / Chemical Monthly》2012,5(3):1107-1114
Abstract
The non-enzyme-catalyzed reaction of reduced glutathione (GSH) with two tumor cell cytotoxic cyclic chalcone analogues was investigated by reversed-phase high-performance liquid chromatography (RP-HPLC). HPLC analysis of the reaction mixtures indicated the formation of two diastereomeric chalcone–GSH adducts in each case, whose structural assignments were supported by MALDI-TOF-MS and HPLC–MS with electrospray ionization (ESI) measurements. Such reactivity accounts for the previously observed effect of the two cyclic chalcone analogues on the in vivo cellular thiol level of Jurkat T cells. 相似文献82.
Andy K. W. Ma Ali A. Alghamdi Kassem Tofailli Nicholas M. Spyrou 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):353-357
Early detection of the red palm weevils (RPW) is a major challenge in agriculture among all kinds of palm trees due to the nature of the insect and the difficulty to trace them through their life stages associated with the tree life. Many methods have been applied for the weevil detection such as X-ray diffraction techniques, fluoroscopy and ultrasound. On the other hand, the idea of tomography has been used for other purposes such as the determination of the age of the tree and for applied environmental studies. Such technology can also reveal the weevil in principle. In this study, we explore the use of X-ray CT for weevil detection with the Monte Carlo method. A model of the stem of a palm tree is developed for simulations. MCNPX is chosen to carry out the simulations for the radiography tally in the code. The tally records the 2D data of the X-ray beams irradiating the tree model. An iterative reconstruction method for cone beam CT is applied to obtain the 3D slices of the tree model. We are exploring the minimum number of projection angles and the detectability of the weevil. We shall also report the sensitivity of weevil detection using X-ray CT with a large set of simulations with different weevil sizes and tree diameters. 相似文献
83.
The reaction of [RuHCl(CO)(PPh3)3] with 4-phenylpyrimidine gave a new ruthenium(II) complex, namely [RuHCl(CO)(PPh3)2(pyrim-4-Ph)]. The complex has been studied by IR and UV?Cvis spectroscopy and by X-ray crystallography. The molecular orbitals of the complex have been calculated by density functional theory. The spin-allowed singlet?Csinglet electronic transitions of the complex have been calculated by time-dependent DFT, and the UV?Cvis spectrum of the compound has been discussed on this basis. The emission properties of the complex were also studied. 相似文献
84.
Lionel Mathelin Olivier P. Le Ma?tre 《Theoretical and Computational Fluid Dynamics》2012,26(5):415-434
This paper describes a rigorous a posteriori error analysis for the stochastic solution of non-linear uncertain chemical models. The dual-based a posteriori stochastic error analysis extends the methodology developed in the deterministic finite elements context to stochastic discretization frameworks. It requires the resolution of two additional (dual) problems to yield the local error estimate. The stochastic error estimate can then be used to adapt the stochastic discretization. Different anisotropic refinement strategies are proposed, leading to a cost-efficient tool suitable for multi-dimensional problems of moderate stochastic dimension. The adaptive strategies allow both for refinement and coarsening of the stochastic discretization, as needed to satisfy a prescribed error tolerance. The adaptive strategies were successfully tested on a model for the hydrogen oxidation in supercritical conditions having 8 random parameters. The proposed methodologies are however general enough to be also applicable for a wide class of models such as uncertain fluid flows. 相似文献
85.
Based on the actual competition in the Chinese property insurance market, the repeated price game model for four oligarchs with different decision rules is built. On the basis of analyzing the stabilities of eight fixed points about the four-dimensional dynamic system, the Nash equilibrium and its local stable region are discussed mainly. Then the complexity of the four-dimensional discrete dynamic system and its evolutionary process are studied. Finally, the delay feedback control method is used to control the chaos. Numerical simulation results have shown that the influence which the change of price adjustment speed has on the movement of dynamic system has a sensitive dependence on the initial conditions, and there is a strong connection between the profit of each oligarch and the price adjustment speed or the control parameters, and the corresponding economic explanation to those phenomena will have important reference values to the realistic problems. 相似文献
86.
Plínio T. Berardo Maurício S. Abrao Maísa L.S. Souza Daniel E. Machado Luiz-Cláudio F. Silva Luiz E. Nasciutti 《Micron (Oxford, England : 1993)》2009,40(5-6):639-645
The composition of sulfated glycosaminoglycans (GAGs) and the tissue distribution of chondroitin sulfate (CS) were analyzed in deeply infiltrating endometriosis (DIE) of rectosigmoid, using metachromatic staining, and biochemical analysis employing electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against CS. The sulfated GAGs were characterized as dermatan sulfate (DS), heparan sulfate (HS) and CS; and DS strongly predominated compared to HS and CS. Immunostaining procedures showed that CS was concentrated in the endometriosis foci, distributed throughout the stroma around the glands. This is the first report describing the composition of sulfated GAGs and the tissue location of CS in DIE by means of histochemical, biochemical and immunohistochemical analyses. These results confirmed that in DIE of rectosigmoid, as in eutopic endometrium [Nasciutti, L.E., Ferrari, R., Berardo, P.T., Souza, M.L.S., Takiya, C.M., Borojevic, R., Abrao, M.S., Silva, L.C.F., 2006. Distribution of chondroitin sulfate in human endometrium. Micron 37, 544–550], CS was the dominant sulfated GAG in stroma of the lesion foci. 相似文献
87.
88.
Xiao-Bo Ma Jing-Lin Zhang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):233-237
Abstract 1,3,2-Diazaphosphetidin-4-one derivatives were synthesized. Their 1H NMR signals at ambient temperature displaed a broad doublet which eventually coalesced before becoming sharp upon warming, and the 13C NMR spectra also showed that the α-and β-carbons of the dialkylamino group were non-equivalent. The phenomena were ascribed to restricted rotation about the exocyclic P—N bond. 相似文献
89.
Arthur E. Martell Ramunas J. Motekaitis Eric T. Clarke Rita Delgado Yizhen Sun Rong Ma 《Supramolecular chemistry》2013,25(3-4):353-363
Abstract In our studies of the stability constants of metal complexes, we have investigated a number of macrocyclic ligands with pendant donor groups. The ligands are characterized by the fact that they have nitrogen donors in the macrocyclic ring and oxygen or sulfur donors in the pendant arms. These ligands represent seven different macrocycles, and by varying the pendant donor groups, ten different ligands are indicated. The affinities of these ligands for fifteen metal ions will be described. The Fe(III) complex of triazanonane with o-hydroxypyridyl or o-hydroxybenzyl pendant donor groups are the most stable ferric complexes ever reported. The In(III) complex of triazacyclononane with pendant mercaptoethyl donor groups, is exceptionally stable. Also, the Ca(II) complex of DOTA probably has the highest stability of any calcium(II) complex. These, and other comparisons will be made on the basis of the thermodynamic stability constant data for the ligands described. 相似文献
90.
Shahul H. Nilar Ngai Ling Ma Thomas H. Keller 《Journal of computer-aided molecular design》2013,27(9):783-792
The one-dimensional model of Hann et al. (J Chem Inf Comput Sci 41(3):856–864) has been extended to include reverse binding and wrap-around interaction modes between the protein and ligand to explore the complete combinatorial matrix of molecular recognition. The cumulative distribution function of the Maxwell–Boltzmann distribution has been used to calculate the probability of measuring the sensitivity of the interactions as the asymptotic limits of the distribution better describe the behavior of the interactions under experimental conditions. Based on our model, we hypothesized that molecules of lower complexity are preferred for target based screening campaigns, while augmenting such a library with moieties of moderate complexities maybe better suited for phenotypic screens. The validity of the hypothesis has been assessed via the analysis of the hit rate profiles for four ChemBL datasets for enzymatic and phenotypic screens. 相似文献