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101.
We developed a fab-wide advanced process control system to control the critical dimension (CD) of gate electrode length in semiconductors. We also developed a model equation that predicts the gate CD by considering the structures of gate electrode and shallow trench isolation. This prediction model was also used to perform a factor analysis of gate CD variation. The effectiveness of the model in controlling feedforward was evaluated by both simulation and experiment. The CD variation of the wafers was improved from 8.9 nm in its 3 sigma without control to 3.5 nm with lot-to-lot feedforward control.  相似文献   
102.
    
New thin film composite membrane system, designated PEC-1000, formed by the acid catalyzed polymerization on the surface of a reinforced-porous supporting membrane, make it possible to produce potable water from seawater by reverse osmosis in a single-stage with a high recovery operation. TDS rejection over 99.9% and stable water fluxes of 0.20–0.30 m3/m2-day (5.0–7.4 gal/ft2-day) have been attained with 3.5% synthetic seawater at an applied pressure of 56Kg/cm2(800psi). For brackish water, sodium chloride rejections of 99.6–99.9% and fluxes of 0.61–0.81m3/m2-day(15.0-20.0 gal/ft2-day) have been attained with 5000 ppm sodium chloride feed at an applied pressure of 40Kg/cm2 (571psi). TDS rejection of 99.8% and water flux of 0.30 m3/m2-day (7.4 gal/ft2-day) have been attained with two- or four-inch diameter PEC-1000 composite membrane elements at an applied pressure of 56Kg/cm2(800psi) in a single-stage synthetic seawater desalination test. This performance is kept for more than 1500 hours in PEC-1000 thin film composite membrane and two-inch diameter element. 280 ppm in TDS and water flux of 0.11 m3/m2 day (2.7 gal/ft2-day) are observed at an applied pressure of 56Kg/cm2-40% water recovery with one four-inch diameter spiral-wound PEC-1000 composite membrane element in a single-stage seawater desalination. This membrane shows high selectivity for low molecular weight valuable organic materials such as ?-caprolactam, dimethylsulfoxide, dimethylformamide. The thickness of ultrathin salt barrier of the composite membrane is found to be 300Å by the Electron Microscopy with special ultrathin section techniques.  相似文献   
103.
104.
Flavour-enhancing components of dried herring fillet (migaki-nishin in Japanese) were isolated and evaluated for their effects on sensory perception. Sensory evaluation revealed that addition of dried herring fillet water-soluble extracts to Japanese noodle soup significantly (P < 0.05) enhanced soup flavour characters, such as thickness, mouthfulness and continuity. The extracts were fractionated by dialysis and chromatography. Fractions containing flavour enhancers were isolated by sensory perception. Results from instrumental analyses showed that the kokumi flavour enhancers in dried herring fillet were creatine and creatinine.  相似文献   
105.
A two-phase, one-dimensional steady model is developed to analyze the coupled phenomena of cathode flooding and mass-transport limiting for the porous cathode electrode of a proton exchange membrane fuel cell. In the model, the catalyst layer is treated not as an interface between the membrane and gas diffusion layer, but as a separate computational domain with finite thickness and pseudo-homogenous structure. Furthermore, the liquid water transport across the porous electrode is driven by the capillary force based on Darcy's law. And the gas transport is driven by the concentration gradient based on Fick's law. Additionally, through Tafel kinetics, the transport processes of gas and liquid water are coupled. From the numerical results, it is found that although the catalyst layer is thin, it is very crucial to better understand and more correctly predict the concurrent phenomena inside the electrode, particularly, the flooding phenomena. More importantly, the saturation jump at the interface of the gas diffusion layer and catalyst layers is captured, when the continuity of the capillary pressure is imposed on the interface. Elsewise, the results show further that the flooding phenomenon in the CL is much more serious than that in the GDL, which has a significant influence on the mass transport of the reactants. Moreover, the saturation level inside the cathode is determined, to a great extent, by the surface overpotential, the absolute permeability of the porous electrode, and the boundary value of saturation at the gas diffusion layer-gas channel interface. In order to prevent effectively flooding, it should remove firstly the liquid water accumulating inside the CL and keep the boundary value of liquid saturation as low as possible.  相似文献   
106.
Nine different combinations of mugi koji (barley steamed and molded with Aspergillus oryzae) and halotolerant microorganisms (HTMs), Zygosaccharomyces rouxii, Candida versatilis, and Tetragenococcus halophilus, were inoculated into chum salmon sauce mash under a non-aseptic condition used in industrial fish sauce production and fermented at 35 ± 2.5 °C for 84 days to elucidate the microbial dynamics (i.e., microbial count and microbiota) during fermentation. The viable count of halotolerant yeast (HTY) in fermented chum salmon sauce (FCSS) mash showed various time courses dependent on the combination of the starter microorganisms. Halotolerant lactic acid bacteria (HTL) were detected morphologically and physiologically only from FCSS mash inoculated with T. halophilus alone or with T. halophilus and C. versatilis during the first 28 days of fermentation. Only four fungal species, Z. rouxii, C. versatilis, Pichia guilliermondii, and A. oryzae, were detected throughout the fermentation by PCR-denaturing gradient gel electrophoresis (PCR-DGGE). In FCSS mash, dominant HTMs, especially eumycetes, were nonexistent. However, under the non-aseptic conditions, undesirable wild yeast such as P. guilliermondii grew fortuitously. Therefore, HTY inoculation into FCSS mash at the beginning of fermentation is effective in preventing the growth of wild yeast and the resultant unfavorable flavor.  相似文献   
107.
The purpose of the present study was to evaluate the safety of ethylene glyco (EG) and 1,6-hexanediol (HD) solutions as experimental dentin primers when subjected to the guinea pig maximization test (GPMT), primary irritation test, cumulative skin irritation test and human patch test. No primary and cumulative skin irritation resulting from the use of 62.5% EG or 45% HD solutions was observed. In the case of GPMT, the animals sensitized with 2-hydroxyethyl methacrylate (2-HEMA) responded to 100% HD. 62.5% EG and 45% HD as dentin primers were safer than 2-HEMA such as a methacrylic primer.  相似文献   
108.
1.30 μm VCSELs using GaAsSb quantum wells, which operate continuous-wave at and above room temperature (RT), are reported. A threshold current as low as 1.2 mA at RT and a maximum CW operating temperature of 70°C are demonstrated  相似文献   
109.
Nonlinear refractive index and absorption coefficient are measured for common semiconductor material such as silicon and organic molecule such as lactose in the terahertz (THz) spectral regime extending from 0.1 to 3 THz. Terahertz pulses with field strengths in excess of 4.4 MV/cm have been employed. Transmittance and the transmitted spectrum were measured with Z-scan and single shot noncollinear electro-optic pump-probe techniques. The THz-induced change in the refractive index (Δn) shows frequency-dependence and a maximum change of \(-~0.128\) at 1.37 THz in lactose and up to \(+~0.169\) at 0.15 THz in silicon was measured for a peak incident THz intensity of 26 GW/cm2. Furthermore, the refractive index variation shows a quadratic dependence on the incident THz field, implying the dominance of third-order nonlinearity.  相似文献   
110.
    
ABSTRACT

For recent boron neutron capture therapy (BNCT), accelerator-based neutron sources have been actively developed in place of reactor-based neutron sources. In this study, a novel neutron energy spectrometer for the daily quality assurance (QA) of BNCT was designed on the basis of a CsI self-activation method for accelerator-based neutron sources. The spectrometer design was optimized in terms of its energy resolution. To verify its applicability to high-intensity BNCT neutron fields, some practical simulations were performed. It was shown that the designed spectrometer was able to evaluate a neutron energy spectrum in approximately 900 s after an instantaneous neutron irradiation. In addition, its energy resolution was sufficient for detecting an unexpected distortion in the spectrum. The results confirm that the designed spectrometer can be employed for the daily QA of BNCT to check that the expected spectrum remains unchanged.  相似文献   
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