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BACKGROUND AND METHODS: Four hundred and eighty-four patients with inflammatory bowel disease underwent clinical examination, ultrasonography, and biochemical liver function tests, to estimate the prevalence of hepatobiliary alterations. The patient group included patients without a history of liver disease. Controls were recruited from patients with functional symptoms. RESULTS: More patients with ulcerative colitis than controls had liver steatosis and increased alkaline phosphatase levels. Factors increasing the probability of liver damage were long-standing disease, the presence of moderate/severe disease activity, and treatment with steroids and mesalazine. A significant association was found between biliary disease and long-standing colitis and also therapy with steroids and mesalazine. Alkaline phosphatase and aminotransferase levels were significantly higher in Crohn's disease patients than in controls. Hepatic and biliary damage was found more commonly in the 1st year after diagnosis. CONCLUSIONS: The monitoring of hepatobiliary function is suggested for patients with inflammatory bowel disease, even in the absence of symptoms and history.  相似文献   
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Dielectric constant and dissipation factor of lead phthalocyanine have been experimentally studied here as functions of frequency and temperature. Dielectric constant increases by one order of magnitude with temperature showing pyroelectric behaviour. It is explained that molecular distortion leads to increased dielectric constant.  相似文献   
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Thin films of indium sulfide (In2S3) micro- and nanorods were successfully prepared by sulfurization of electrodeposited metal indium layers. The films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and UV-vis spectroscopy. From XRD and TEM observations it was concluded that the In2S3 nanorods and microrods have ∼50 nm and ∼0.5 μm diameter, respectively. A plausible top-growth mechanism was proposed for the formation of the nanorods in which the hydroxide layer was found to play an important role. The micro- and nanorods showed optical bandgap of ∼2.2 and ∼2.54 eV, respectively. This facile and cost effective method may be extended to fabricate other metal chalcogenide nanostructures on solid substrates.  相似文献   
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CdS nanorods with varying dimensions were synthesized by solvothermal process. It was observed that the anions present with the Cd-salts play an important role in determining the dimensions of the CdS nanorods. The crystalline nature of the sources was found to play a crucial role in determining the phase of the products. The nature of the sulfur source, molar ratio of the precursors, filling fraction of the solvent, and the synthesis temperature play important role in defining the size and shape of the products. By controlling the experimental parameters it was possible to control the dimension of the CdS nanorods within a certain range (diameter of the nanorods could be varied within a wide range from approximately 7 to 100 nm by varying the temperature within 100-250 degrees C). Optical absorption, photoluminescence, and Raman studies of these samples were carried out to characterize the CdS nanorods.  相似文献   
37.
Mn and Cu doped ZnS nanoparticles in powder form were prepared by a simple solvothermal route. Particle size and crystal structure of the products were investigated through X-ray diffraction study revealing the formation of cubic ZnS nanoparticles of average diameter 2.5 nm. Particle size was also verified by the high resolution transmission electron microscopic images. Blue emission at approximately 445 nm was observed from the undoped sample, which was attributed to the presence of large surface defects. With increasing doping concentration the defect related emission gradually quenches and subsequently the impurity related emissions appeared. Mn doped samples exhibited orange emission at approximately 580 nm which may be attributed to the transition between (4)T1 and (6)A1 energy levels of the Mn2+ 3d states. Whereas, the Cu doped ZnS nanoparticles exhibited a red shifted strong blue emission at approximately 466 nm which is attributed to the transition of the electrons from the surface states to the 't2' levels of Cu impurities.  相似文献   
38.
Use of biologically modified gold nanoparticles (GNPs) as molecular vehicle to ferry potential anti-cancer drug berberine hydrochloride (BHC) using folic acid (FA) as targeting molecule is reported in this work. A tropical fruit peel, Trapa bispinosa is used to fabricate highly monodispersed GNPs, passivated with essential functional groups which were used as linkers to attach FA and BHC via amide linkage. Flocculation Parameter (FP) of biologically synthesized GNPs was calculated under different salt concentrations which were found to be very ideal under a physiological condition. Various statistical models were used to find drug release profile out of which Higuchi was found to be the most ideal. GNP–FA–BHC complexes were found to be active against folic acid expressing HeLa cells.  相似文献   
39.
Bio-composite scaffolds were fabricated by impregnating 10, 20, 30, 40 and 50% ZrO2 content with the β-TCP matrix to heal load bearing large size bone defects. The composite scaffolds were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and mechanical testing. The in vitro degradation of scaffolds was calculated by immersing the samples in phosphate buffer saline for a period of 21 days. Biocompatibility was evaluated by XTT assay using human Osteosarcoma cell line (MG-63). Results include scaffold surface morphology, overall porosity, phase transformation, bonding, compressive strength, biodegradability and cytotoxicity with an increase in ZrO2 percentages. The conclusions proved that β-TCP scaffold with 30% ZrO2 content exhibits the best-required properties for the application in the field of bone tissue regeneration.  相似文献   
40.
Patient specific HA/β-TCP scaffold were fabricated using an indirect fabrication approach which involves the application of rapid prototyping technology. β-TCP powder with 10, 20 and 30 % HA concentrations were analyzed for different sintering temperatures. Scaffolds were evaluated by Scanning Electron Microscopy, X-ray diffraction, compression tests, Fourier transform infrared spectroscopy and cytotoxicity tests using human osteosarcoma cell line. Results include HA/β-TCP scaffold porosity, volumetric shrinkage, mechanical properties, bonding, structural phase change and cytotoxicity.  相似文献   
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