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121.
122.
M. Hussain N. Thai Hung N. Abbas R. A. Khera I. Malik T. Patonay N. Kelzhanova Z. A. Abilov A. Villinger P. Langer 《Journal of heterocyclic chemistry》2015,52(2):497-505
Arylated benzofurans were prepared by regioselective Suzuki–Miyaura cross‐coupling reactions of 2,3‐dibromobenzofuran. The reactions proceeded with very good site‐selectivity in favor of the more electron deficient position 2. The Suzuki–Miyaura reactions of 2,3,5‐tribromobenzofuran also proceeded in favor of position 2. 相似文献
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Jahangeer Patujo Amin Badshah Raja Azadar Hussain Muhammad Nawaz Tahir Shaista Tahir Muhammad Khawar Rauf 《中国化学会会志》2015,62(11):1020-1027
In the present work new nitro substituted thioureas, and their copper complexes have been synthesized and characterized by FTIR and multinuclear NMR techniques. Some of the compounds namely 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐1), 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐2) and 1‐benzoyl‐3‐(2‐methoxy‐4‐nitrophenyl) thiourea (A‐2) have also been characterized by single crystal XRD. All the synthesized compounds have been screened for DNA binding potencies (using cyclic voltametry, UV‐vis spectroscopy) and free radical scavanging activities. 相似文献
125.
Diorganotin(IV) Complexes with Monohydrate Disodium Salt of Iminodiacetic Acid: Synthesis,Characterization, Crystal Structure and Biological Activities 下载免费PDF全文
Shabbir Hussain Saqib Ali Saira Shahzadi Corrado Rizzoli Muhammad Shahid 《中国化学会会志》2015,62(9):793-802
Diorganotin(IV) derivatives have been synthesized by the reaction of R2SnL2 (R=n‐Bu 1 , Ph 2 ) with monohydrate disodium salt of iminodiacetic acid ( Na2L ) in 1 : 1 M/L ratio under reflux conditions. The compounds have been characterized by FT‐IR, NMR (1H and 13C) spectoscopy, electron ionization mass spectrometry (EIMS), thermogravimetric analyses (TGA) and single crystal XRD. FTIR data indicates a mono‐dentate binding mode of the carboxylic acid group as well as participation of the amino nitrogen and aqua oxygen in coordination with organotin(IV) moieties. NMR data demonstrates a tetra‐coordinated environment around tin(IV) in solution. Mass spectrometric and thermogravimetric analyses verify the close similarities between the molecular structures of both complexes. The thermal stability of diphenyltin(IV) derivative ( 2 ) was found slightly higher than that of the free ligand ( Na2L ). Single crystal X‐ray analysis of the complex 1 have shown a hexa‐coordinated geometry around Sn(IV) with trans configuration. There are evidences for the existence of intermolecular hydrogen bonding in the structure of the complexes. The products displayed significant antibacterial and antifungal activities in contrast to the biologically inactive ligand precursor. However, the hemolytic cytoxicity of the complexes was comparatively high than the free ligand. 相似文献
126.
Present communication reports the preparation of Langmuir monolayer of water-soluble anionic dye Congo red (CR) by allowing it to adsorb from the aqueous subphase onto the preformed Langmuir monolayer of anionic stearic acid using divalent metal cations Mg2+ as mediator. Isotherm and compressibility studies of SA-Mg-CR hybrid monolayer gave valuable information about the molecular organisation in the Langmuir monolayer. Absorption spectroscopic studies revealed the formation of H-aggregates in the hybrid Langmuir–Blodgett (LB) films fabricated at lower salt concentration in the subphase. Atomic Force Microscopic image gave visual evidence of distinct nanocrystalline domains in the LB monolayer film. 相似文献
127.
In this article, we consider a portfolio optimization problem of the Merton’s type with complete memory over a finite time horizon. The problem is formulated as a stochastic control problem on a finite time horizon and the state evolves according to a process governed by a stochastic process with memory. The goal is to choose investment and consumption controls such that the total expected discounted utility is maximized. Under certain conditions, we derive the explicit solutions for the associated Hamilton–Jacobi–Bellman (HJB) equations in a finite-dimensional space for exponential, logarithmic, and power utility functions. For those utility functions, verification results are established to ensure that the solutions are equal to the value functions, and the optimal controls are also derived. 相似文献
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129.
Shah Hussain Cornelia Pezzei Yüksel Güzel Matthias Rainer Christian W. Huck Günther K. Bonn 《Analytica chimica acta》2014
An efficient blood plasma clean-up method was developed, where methanol protein precipitation was applied, followed by zirconium silicate assisted exclusion of residual proteins. A strong binding of zirconium (IV) silicate to the proteins enabled the elimination of remaining proteins after solvent deproteinization through a rapid solid-phase extraction (SPE) procedure. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF MS) was used for monitoring the proteins during clean-up practice applied to human plasma samples. The proteins were quantified by colorimetric detection using the bicinchoninic acid (BCA) assay. The presented analytical strategy resulted in the depletion of >99.6% proteins from human plasma samples. Furthermore, high-performance liquid chromatography hyphenated to diode-array and electrospray ionization mass spectrometric detection (HPLC–DAD/ESI MS) was applied for qualitative and quantitative analysis of the caffeoylquinic acids (CQAs) and their metabolites in human plasma. The procedure demonstrated high recoveries for the standard compounds spiked at different concentrations. Cynarin and chlorogenic acid were recovered in the range of 81–86% and 78–83%, respectively. Caffeic acid was extracted in the excess of 89–92%, while ferulic acid and dihydroxyhydrocinnamic acid showed a recovery of 87–91% and 92–95%, respectively. The method was partially validated in accordance with FDA-Industry Guidelines for Bioanalytical Method Validation (2001). The presented scheme improves the clean-up efficacy of the methanol deproteinization, significantly reduces the matrix effects and provides a great analytical tool for the isolation of small molecules from human plasma. 相似文献
130.
Humayun Ajaz Sajjad Hussain Muhammad Altaf Helen Stoeckli‐Evans Anvarhusein A. Isab Rashid Mahmood Shahnila Altaf Saeed Ahmad 《中国化学》2011,29(2):254-258
Antimony(III) complexes of thioamides [thioamides=thiourea (Tu), N,N′‐dimethylthiourea (Dmtu), tetramethylthiourea (Tmtu), imidazolidine‐2‐thione (Imt) and diazinane‐2‐thione (Diaz)] with the general formulae, Sb(thione)nCl3 (n=1, 2, 2.5, 3) were prepared and characterized by elemental analysis, IR and NMR (1H, 13C) spectroscopic methods. The spectral data of the complexes are consistent with the coordination of the thiones to antimony(III). The crystal structure of one of them, {[Sb(Imt)2Cl2]2(μ2‐Imt)}Cl2 ( 1 ), was determined by X‐ray crystallography, which shows that the complex is dinuclear consisting of two [Sb(Imt)2Cl2] units bridged by an Imt molecule. In 1 , the antimony atom is bonded to two chlorine atoms, two sulfur atoms of coordinated Imt molecules and one sulfur atom of a bridging Imt molecule. The antimony environment can be considered to be distorted octahedral with one Cl? ion weakly bound to antimony. 相似文献