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31.
K. Anitha S. Athimoolam S. Natarajan 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o567-o570
In the structure of l ‐prolinium picrate, C5H10NO2+·C6H2N3O7−, the Cγ atom of the pyrrolidine ring has conformational disorder. Both the major and minor conformers of the pyrrolidine ring adopt conformations intermediate between a half‐chair and an envelope. Both the cation and anion are packed through chelated three‐centred N—H⋯O hydrogen bonds. The prolinium cation connects two different picrate anions, leading to an infinite chain running along the b axis. In 2‐methylpyridinium picrate, C6H8N+·C6H2N3O7−, the cations and anions are packed separately along the a axis and are interconnected by N—H⋯O hydrogen bonds. Intramolecular contacts between phenolate O atoms and adjacent nitro groups are identified in both structures. A graph‐set motif of R12(6) is observed in both structures. 相似文献
32.
The crystal structure of [C10N2H10]2[P2Mo5O21(OH)2] · 2H2O, contains the heteropolyanion, [P2Mo5O21(OH)2]4—, together with diprotonated 4, 4′‐bipyridine. The heteropolyanion is built up from five MoO6 octahedra sharing four common edges and one common corner, capped by two PO3(OH) tetrahedra. The structure is stabilized by hydrogen bonds involving the hydrogen atoms of the 4, 4′‐bipyridine, water molecules and the oxygen atoms of the pentamolybdatobisphosphate. This is the first example that this kind of cluster could be isolated in the presence of a poly‐functional aromatic molecule ion. Crystal data: triclinic, P1¯ (No. 2), a = 9.983(2)Å, b = 11.269(2)Å, c = 17.604(4)Å, α = 73.50(3)°, β = 84.07(3)°, γ = 67.96(3)°; V = 1760.0(6)Å3; Z = 2; R1 = 0.037 and wR2 = 0.081, for 9138 reflections [I > 2σ(I)]. 相似文献
33.
Vanadate garnet systems namely Ca2NaMg2V3O12, individually doped with Dy and Sm and also co-doped with both the RE ions were synthesized via the solid-state reaction route and their photoluminescence (PL) properties were investigated. The method of synthesis was verified by the formation of single phase compound through X-ray diffraction (XRD) studies. Existence of energy transfer in between the host and the dopant ions was established by PL investigation. Color coordinates of all the compounds were calculated and plotted on the CIE diagram. It was seen that the co-doped system has a near white light emission. It was concluded that this single phosphor is capable of converting the ultraviolet emission of a UV-LED into white light. 相似文献
34.
Synthesis,characterization and biological screening studies of mixed ligand complexes using flavonoids as precursors
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Flavonoids are a group of plant phenolics that provide various health benefits through cell signalling pathways and antioxidant effects. In the present study, a new series of mixed ligand complexes of Co(II), Ni(II), Cu(II) and Zn(II) were synthesized by incorporating curcumin and quercetin flavonoid precursors. The structural features of the synthesized complexes were explored using elemental analysis, thermogravimetric analysis, UV–visible, infrared, NMR, mass and electron paramagnetic resonance spectral analyses and conductivity measurements. These data support an octahedral geometry of the synthesized complexes. In silico biological activity score for the ligand was predicted using PASS online software. ADMET properties were studied using VLS3D online software. Anti‐inflammatory and antioxidant activities were experimentally validated which prove that theoretical predictions are in agreement with the experimental results. Interestingly the synthesized complexes interact with calf thymus DNA through groove binding mode. Moreover, they have good potential to cleave pUC19 DNA. Minimum inhibitory concentration values of the synthesized complexes reveal that they have better antimicrobial efficacy than the ligands. 相似文献
35.
Manimaran Kumar Murugesan Subban Ragavendran Chinnasamy Balasubramani Govindasamy Natarajan Devarajan Ganesan Abirami Seedevi Palaniappan 《Journal of Cluster Science》2021,32(5):1229-1240
Journal of Cluster Science - The titanium dioxide nanoparticles (TiO2NPs) were synthesized by the aqueous extract from P. djamor. The UV–Vis spectrum of TiO2NPs showed maximum absorption at... 相似文献
36.
Biological contour,molecular docking and antiproliferative studies of DNA targeted histidine based transition metal(II) complexes: Invention and its depiction
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A novel series of histidine derived transition metal complexes were synthesized and characterized by multispectral techniques such as UV‐Vis., FT IR, EPR, NMR, ESI‐mass analysis and other physico‐chemical methods like elemental analysis, molar conductivity, magnetic susceptibility. The synthesized compounds were attempted for their biological prospective. The biological studies involved are DNA interaction (binding and damage), antimicrobial, antioxidant, antiproliferative and molecular docking. DNA interaction studies were carried out with the help of UV‐Vis absorption titration, viscosity measurement and cyclic voltammetric techniques which revealed that the synthesized compounds could interact with CT‐DNA through intercalative binding mode. A gel electrophoresis assay demonstrated the ability of complexes to cleave the supercoiled pUC18 DNA. The antioxidant property shows that the metal complexes have preferable ability to scavenge hydroxyl radical than the ligand. Moreover, the antimicrobial assay indicates that these complexes are good antimicrobial agents against various pathogens. Furthermore, the in vitro antiproliferative activities of the complexes were examined on HeLa, Hep G2 and NIH 3 T3 cell lines using an MTT assay. The morphological changes were investigated using Hoechst 33258 staining apoptosis assay. In addition, molecular docking studies were executed to considerate the nature of binding of the synthesized complexes with protein and DNA. 相似文献
37.
A cost‐effective curvature calculation approach for interfacial flows on unstructured meshes
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We present a simple and cost‐effective curvature calculation approach for simulations of interfacial flows on structured and unstructured grids. The interface is defined using volume fractions, and the interface curvature is obtained as a function of the gradients of volume fractions. The gradient computation is based on a recently proposed gradient recovery method that mimicks the least squares approach without the need to solve a system of equations and is quite easy to implement on arbitrary polygonal meshes. The resulting interface curvature is used in a continuum surface force formulation within the framework of a well‐balanced finite‐volume algorithm to simulate multiphase flows dominated by surface tension. We show that the proposed curvature calculation is at least as accurate as some of the existing approaches on unstructured meshes while being straightforward to implement on any mesh topology. Numerical investigations also show that spurious currents in stationary problems that are dependent on the curvature calculation methodology are also acceptably low using the proposed approach. Studies on capillary waves and rising bubbles in viscous flows lend credence to the ability of the proposed method as an inexpensive, robust, and reasonably accurate approach for curvature calculation and numerical simulation of multiphase flows. 相似文献
38.
Numerical Algorithms - In this paper, we employ the virtual element method for the numerical solution of linear thermo-elastic problems in two dimensions. The framework is implemented within the... 相似文献
39.
V. C. Adya M. Mohapatra Nimai Pathak Mithlesh Kumar N. S. Hon S. K. Thulasidas M. J. Kulkarni V. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2016,307(1):341-346
This work presents the investigation of some commercially available and commonly used Si3N4 foils prepared with LPCVD technique. The density and the stoichiometry of these films were determined by Rutherford backscattering spectroscopy and profilometry, while the study of impurities was achieved with particle induced X-ray emission method. It was found that the density of the studied Si3N4 films is significantly less (~2.71 g cm?3), while the stoichiometry is close to the values of the bulk material. The results were verified by measuring the ion energy loss through the films by scanning transmission ion microscopy. 相似文献
40.
Ranjini Natarajan Charles E. McCulloch 《Journal of computational and graphical statistics》2013,22(3):267-277
Abstract This article demonstrates by example that the use of the Gibbs sampler with diffuse proper priors can lead to inaccurate posterior estimates. Our results show that such inaccuracies are not merely limited to small sample settings. 相似文献