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101.

Thiazolidinedione derivatives have been used as anti-hyperglycemic agents in diabetic patients since last decade. In the present study, a series of N-substituted-5-(furan-2-ylmethylene)thiazolidine-2,4-dione derivatives were synthesized and characterized by 1H-NMR, 13C-NMR and mass spectra. The introduction of the alkyl/haloalkyl moiety onto the amidic nitrogen of the thiazolidine-2,4-dione ring was intended to enhance the anti-hyperglycaemic activity, which was further tested in vivo by using alloxan-induced diabetic laca mice. Molecular docking simulation studies further helped in understanding the nature of the interactions and the binding mode of ligands inside the active site of the protein tyrosine phosphatase 1B enzyme, which negatively regulates the insulin signaling pathway. The compounds were screened for in-vivo anti-hyperglycaemic activity in which compounds 9 and 10 have exhibited significant decreases in blood glucose level comparable to that of pioglitazone.

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Higher cost and lower availability of enriched isotopic materials are the major constraints in targets fabrication of isotopes. If the distribution of the vapor flux is not controlled in the evaporation, large amount of material is wasted. Minimizing the material wastage is important in the fabrication of targets of expensive isotopes. Evaporation sources have been designed and machined at Inter-University Accelerator Centre (IUAC) for minimizing the consumption of materials in evaporation. Details of different types evaporation sources used in Target development laboratory at IUAC for minimizing the wastage of target material in target fabrication is discussed in this report.  相似文献   
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We have studied the electronic structure of unoccupied states measured by O K-edge and Cu L-edge x-ray absorption spectroscopy (XAS), combined with crystal structure studied by high resolution powder x-ray diffraction (HRPXRD), of charge-compensated layered superconducting CaxLa1−xBa1.75−xLa0.25+xCu3Oy (0≤x≤0.4 and 6.4≤y≤7.3) cuprate. A detailed analysis shows that, apart from hole doping, chemical pressure on the electronically active CuO2 plane due to the lattice mismatch with the spacer layers greatly influences the superconducting properties of this system. The results suggest chemical pressure to be the most plausible parameter to control the maximum critical temperatures (Tcmax) in different cuprate families at optimum hole density.  相似文献   
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Flow, Turbulence and Combustion - The effect of hydrogen ( $$\mathrm {H}_{\mathrm {2}}$$ ) enrichment on the flame-holding characteristics of two natural gas jet flames in crossflow is investigated...  相似文献   
108.
Many human diseases occur due to the over or under-expression of genes which can be corrected either by silencing or over-expression, respectively by transforming with specific nucleic acid (NA). NA transformation for medical purposes to alter the cellular gene expression is challenging because NA cannot cross efficiently the cellular biomembrane. One option, the viral vectors, is risky for patients and, the non-viral vectors have lower transformation efficiency. From the past few years, nanoparticles (NPs) are being studied extensively for their use as a vector to deliver NA. They are of a sub-micron size, have a large surface area, rapid absorption ability and can reach inside of the cells. These properties make them a suitable gene carrier. NPs types - organic, inorganic, organic/inorganic hybrid and polymeric NPs, having different properties that can be used to deliver the NA. They possess various properties like biocompatibility, targeted delivery of gene, controlled release of NA which makes them suitable for different uses. In this review, we are describing and comparing various methods to synthesize various kinds of NPs and how they can be conjugated with NA. A series of modifications in NPs to form the polyplex are also discussed along with the varying outcomes in terms of changes in the gene expression and its cytotoxicity towards different cell lines. This review is helpful for nano-scientists to decide which method to be followed for a specific need via controlling gene expression.  相似文献   
109.
In recent years, water pollution and pesticide accumulation in the food chain have become a serious environmental and health hazard problem. Direct determination of these contaminants is a difficult task due to their low concentration level and the matrix interferences. Therefore, an efficient separation and preconcentration procedure is often required prior to the analysis. With the advancement in nanotechnology, various types of magnetic core–shell nanoparticles have successfully been synthesized and received considerable attention as sorbents for decontamination of diverse matrices. Magnetic core–shell nanoparticles with surface modifications have the advantages of large surface‐area‐to‐volume ratio, high number of surface active sites, no secondary pollutant, and high magnetic properties. Due to their physicochemical properties, surface‐modified magnetic core–shell nanoparticles exhibit high adsorption efficiency, high rate of removal of contaminants, and easy as well as rapid separation of adsorbent from solution via external magnetic field. Such facile separation is essential to improve the operation efficiency. In addition, reuse of nanoparticles would substantially reduce the treatment cost. In this review article, we have attempted to summarize recent studies that address the preconcentration methods of pesticide residue analysis and removal of toxic contaminants from aquatic systems using magnetic core–shell nanoparticles as adsorbents.  相似文献   
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Samples with nominal composition Tl2Ba2Cu1.2 (copper-rich Tl-2201) were calcined at various temperature, i.e. from 865 °C to 910°C and for various durations (10–20 h). The samples were sintered for 31/2 min at various temperatures. The X-ray powder diffraction pattern indicates that most of the Tl-Ba-Cu samples (Tl-2201) are single-phase materials. All the lines in the X-ray pattern are indexable on a tetragonal unit cell showing tetragonal symmetry having space group 14/mmm with a=3.86 Å C=23.11 ± 0.06 Å as unit cell parameters. R−T and AC susceptibility measurements show Tonc, from 90 to 104 K. There is an elongation of the c-axis (c=23.24 Å) for the sample showing the highest Tc. Wet chemical analysis confirms the deficiency of thallium. This suggests some substitution of Cu in place of thallium which leads to an increase in the average oxidation state of copper, responsible for the creation of holes (charge carriers).  相似文献   
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