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We have used the condensation method to synthesize 2-acetyl-5-methylsemicarbazone ligand. Manganese(II) and Cobalt(II) complexes having formula [ML2]X2 were synthesized where M = Mn(II) and Co(II), L = ligand, X = Cl−, CH3COO−, NO3−, ½SO42−. The characterization data suggests the octahedral geometry for all the synthesized complexes. Tridentate nature of the 2-acetyl-5-methylsemicarbazone ligand was revealed by IR studies. Molar conductance analysis suggested the electrolytic nature of the complexes. The theoretical study includes geometrical optimization, HOMO-LUMO energy gap, energetic parameters and dipole moment. These results also confirmed the tridentate nature of the ligand and the octahedral geometry of complexes. The molecular electrostatic potential (MEP) study suggested the reactive sites for an electrophilic or nucleophilic attack in the ligand. We tested the synthesized compounds for their antifungal and antibacterial action via well diffusion method and found that parent ligand after the coordination with the metal ion showed more effective inhibition against bacteria and fungi. 相似文献
4.
The conventional condensation and refluxing process was employed to synthesize Ni(II) and Cu(II) complexes of Methylcarbamatethiosemicarbazone ligand. Reactions were carried out at the pH of 7. The molar ratio of the ligand and metal salt was 2:1. The structures of the synthesized metal complexes were suggested by different analytical techniques such as magnetic susceptibility, molar conductance, IR, EPR and UV spectroscopy. Experimental studies confirmed the octahedral geometry for all the complexes. The geometry of the ligand and complexes were also confirmed by theoretical studies. The complexes were investigated for biological action against pathogenic fungi (C. krusei, C. albican) and bacteria (S. aureus, E. coli). The antimicrobial results confirmed superior inhibition potential of the metal complexes as compared with the parent ligand. The enhanced antimicrobial activities might be due to the chelation. Molecular-docking assays confirmed the strong interaction of ligand with target antimicrobial protein DNA gyrase-B. 相似文献
5.
This study addresses the magnetic interaction between paramagnetic metal ions and the radical ligands taking the [CuII(hfac)2(imVDZ)] and [MII(hfac)2(pyDTDA)] (imVDZ=1,5-dimethyl-3-(1-methyl-2-imidazolyl)-6-oxoverdazyl; hfac=(1,1,1,5,5,5)hexafluroacetylacetonate; pyDTDA=4-(2′-pyridyl)-1,2,3,5-dithiadiazolyl), (M=Cu, Ni, Co, Fe, Mn) compounds as reference systems. The coupling between the metal and ligand spins is quantified in terms of the exchange coupling constant (J) in the platform of density functional theory (DFT) and the wave function-based complete active space self-consistent field (CASSCF) method. Application of DFT and broken symmetry (BS) formalism results ferromagnetic coupling for all the transition metal complexes except the Mn(II) complex. This DFT-BS prediction of magnetic nature matches with the experimental finding for all the complexes other than the Fe(II)-pyDTDA complex, for which an antiferromagnetic coupling between high spin iron and the thiazyl ligand has been reported. However, evaluation of spin state energetics through the multiconfigurational wave function-based method produces the S=3/2 ground spin state for the iron-thiazyl in parity with experiment. Electronic structure analyses find the overlap between the metal- and ligand-based singly occupied molecular orbitals (SOMOs) to be one of the major reasons attributing to different extent of exchange coupling in the systems under investigation. 相似文献
6.
S. N. V. M. S. Gupta A. K. Nayak U. B. Misra Balaji Rao Yarasi C. Phani Babu G. Kalyanakrishnan 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(3):571-579
The present paper describes a new analytical method developed for direct determination of boron in steels using radio frequency glow discharge optical emission spectrometer. “Single parameter alternative method” technique has been used to optimize the various experimental conditions of glow discharge plasma such as forward power, gas pressure inside plasma chamber, pre-integration time, and integration time. Different emission lines for boron were studied and inter element interference effect is also discussed in the paper. A complete statistical analysis has been done to validate the developed method. A RSD of less than ±5% is achieved for boron in the range of 0.0010–0.020% in Steels using this method. 相似文献
7.
Metal complexes of 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) are being used as a chiral catalysts in many organic reactions. This review highlights recent developments on synthesis of metal BINAPs and its application in various organic synthesis. The studies done on the application of metal BINAPs show a unique reactivity, which enables its use in entirely different sets of chemical transformation. 相似文献
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A.?G.?Pacheco G.?Salgado-Morán L.?Gerli-Candia R.?Ramírez-TagleEmail author D.?Glossman-Mitnik A.?Misra A.?F.?de Carvalho Alcantara 《Journal of Structural Chemistry》2017,58(2):261-267
Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most frequently prescribed drugs and have multiple therapeutic uses. These drugs are predominantly used for the treatment of musculoskeletal diseases because of their analgesic, antipyretic, and antiplatelet activities. Oxicams constitute an interesting class of organic compounds and have been investigated in the search for new analgesic and anti-inflammatory drugs. In the present work, a theoretical investigation of the molecular structure and spectroscopic properties of a series of five oxicams in different solvents was performed using density functional theory (DFT) methods. The geometric optimizations of the oxicams were carried out using the M06 density functional and the CBSB7 basis set. The infrared data were all obtained at the same theoretical level. The UV-Vis absorption and NMR data of some oxicams were calculated using the DFT and CBSB3 basis sets. The analysis of structural parameters, particularly the bond length and spectroscopic data, indicated that interactions occurred between the hydrogen bond types for 4-meloxicam, isoxicam, and normeloxicam. Stereoelectronic interactions caused by the substitution of alkyl groups caused the bond lengths to elongate. Similarly, the substitution of heteroatoms, such as nitrogen, sulfur, or oxygen, increased the bond lengths and angular stresses. 相似文献
9.
Leibniz algebras are certain generalization of Lie algebras. In this paper, we give the classification of four-dimensional non-Lie nilpotent Leibniz algebras. We use the canonical forms for the congruence classes of matrices of bilinear forms and some other techniques to obtain our result. 相似文献
10.
Ezio Venturino P.K. Tiwari A.K. Misra 《Mathematical Methods in the Applied Sciences》2017,40(4):1081-1094
Water bodies located nearby cities are much prone to pollution, especially in the developing countries, where effluents treatment facilities are generally lacking. The main reason for this phenomenon is the increasing population in the cities, and the large number of industries located near them. This leads to generation of huge amounts of domestic and industrial sewage that is discharged into the water bodies, increasing their organic pollutant load and resulting in the depletion of dissolved oxygen. In this paper, we propose a mathematical model for this situation, focusing especially on the resulting quality of the water, determined by the level of dissolved oxygen. The model also accounts for resources needed for the population survival and for the industrial operations. In addition, we describe also the decomposition of organic pollutants by bacteria in the aquatic medium. Feasibility conditions and stability criteria of the system's equilibria are determined analytically. The results show that human population and industries are relevant influential factors responsible for the increase in organic pollutants and the decrease in dissolved oxygen in the water body, in the sense that they may exert a destabilizing effect on the system. The numerical simulations confirm the analytical results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献