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Here, we show, for the first time, the use of graphitic carbon nitride (g-C3N4) nanosheets to improve the resolution and efficiency of protein separation in gel electrophoresis. By loading 0.04% (m/v) g-C3N4 nanosheets into the polyacrylamide gel at 25 °C, the thermal conductivity increased approximately 80% which resulted in 20% reduction in Joule heating and overall increase of separation efficiency. Also, polymerization of acrylamide occurred in the absence of tetramethylethylenediamine (TEMED) when the polyacrylamide gel contained g-C3N4 nanosheets. Hence, the g-C3N4 act simultaneously as a polymerization catalyst as well as heat sinks to lower Joule heating effect on band broadening. 相似文献
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Mohammad Hossein Habibi Payman Bagheri 《Journal of the Iranian Chemical Society》2017,14(8):1643-1649
Spinel cobalt manganese oxide nano-composites were grown on nanosheets using acetate precursors in mono-ethylene glycol. Crystal structures and morphologies of nano-composites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy and energy dispersive X-ray spectroscopy to characterize the element composition. Fourier transform infrared spectroscopy was used for structural characterization and UV–Vis diffuse reflectance spectra (UV–Vis DRS) for optical properties. XRD results showed tetragonal spinel cobalt manganese oxide (Co,Mn)(Co,Mn)2O4 and cubic spinel cobalt manganese oxide MnCo2O4.5 structural phases. The crystallite size calculated by the Scherrer’s equation was 17 nm. The morphological studies displayed the existence of 40–63 nm nano-powders grown on nanosheets with a good degree of crystallization. Optical properties of cobalt manganese oxide nano-composites exhibit absorbance edge, and the band gap calculated from UV–Vis DRS results was 1.78 eV. FTIR spectra indicated that hydroxyl and oxide groups were major active sites. The absorption bands observed at 656 and 568 cm?1 are related to stretching vibrations of Mn–O and Co–O, respectively. The photocatalytic activities of nano-composites for photocatalytic mineralization of Acid Black 1 textile dye showed an outstanding performance. Photocatalytic process yielded 91% total organic carbon removals within 2.5 h of irradiation. The enhanced photocatalytic activity was attributed to better charge separation of the photo-generated electron–hole pairs in nano-composite. 相似文献
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Hossein Naeimi Khadijeh Rabiei Fariba Salimi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2351-2357
A simple, efficient, and cost-effective method has been developed for the synthesis of N,N′-bis(2-hydroxybenzylidene)-1,1-diaminoalkanes through one-pot, three-component reaction of salicylaldehyde, aliphatic aldehydes, and ammonium nitrate in the presence of a base under solvent-free conditions at room temperature. 相似文献
920.
Vahabodin Goodarzi Seyed‐Hassan Jafari Hossein Ali Khonakdar Seyed‐Ali Monemian Rüdiger Hässler Dieter Jehnichen 《Journal of Polymer Science.Polymer Physics》2009,47(7):674-684
Crystalline structures, nonisothermal crystallization behavior and surface folding free energy of polypropylene (PP)/poly(ethylene‐co‐vinyl acetate) (EVA) blend‐based organically modified montmorillonite (OMMT) nanocomposites were investigated by use of wide angle X‐ray scattering (WAXS) and differential scanning calorimetry (DSC) techniques. Nonisothermal crystallization kinetic analysis was performed using Avrami equation modified by Jeziorny as well as combined Avrami‐Ozawa method. Surface folding free energy and activation energy for PP and nanocomposite samples were also determined employing Hoffman‐Lauritzen's and Vyazovkins's approaches, respectively. The results obtained from transmission electron microscopy (TEM) showed that presence of EVA, which attracts most of the layered silicates, reduces number density of heterogeneous nuclei in the matrix and as a consequence, decreases the nucleation rate. Incorporation of EVA, PP‐g‐MA and OMMT results in a decrease of the chain surface folding free energy level. It was shown that although, OMMT acts as a barrier against the PP macromolecular motion but interestingly, it increases the overall crystallization rate. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 674–684, 2009 相似文献