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81.
Acetaldehyde (AA) accumulates in the oral cavity after alcohol intake and is responsible for an increased risk of alcohol-related upper aerodigestive tract (UDAT) cancer among aldehyde dehydrogenase 2-inactive heterozygotes in particular. Thus, the removal of AA from the saliva to a level below its mutagenic concentration (50 μM) after drinking is a potentially straightforward method for reducing the risk of alcohol-related UDAT cancer. Although microbial cells with AA-decomposing activity could potentially serve as a useful agent for the catalytic removal of AA from the saliva without the supplemental addition of cofactors, these cells generally exhibit strong AA-producing activity from ethanol, which is present in excess (50mM) over AA (100 μM) in the saliva after drinking. In this study, we observed that Gluconobacter kondonii (GK) cells efficiently decomposed salivary AA (100-390 μM) without the supplemental addition of cofactors irrespective of the type of alcoholic beverages consumed, even in the presence of an excess of ethanol (63 mM). Hydrogen peroxide, which is carcinogenic in animal experiments, was not produced because of the AA removal. The GK cells incubated at 45 °C and pH 3.5 for 15 h were killed, but they retained 80% of their original AA-decomposing activity. The treated cells were used as nonviable microcapsules that harbor a membrane-bound AA-decomposing activity.  相似文献   
82.
We investigated the membrane-stabilizing effect of three synthesized polar carotenoids, thermozeaxanthin (TZ), zeaxanthin glucoside (ZG) and zeaxanthin (Z), using the fluorescent calcein-leakage measurement from the calcein-entrapped liposomes composed of dipalmitoylphosphatidylcholine (DPPC). The addition of TZ stabilized the liposomal membranes composed of DPPC at pH values ranging from 4.0 to 10.0. The addition of three carotenoids, TZ, ZG and Z, stabilized the membrane at acidic and neutral pH values ranging from 4.0 to 7.5. The values of leakage were lower at 30 °C and highest at 40 °C, and subsequently, gradually decreased at the higher temperature. The addition of TZ and Z stabilized the membranes, whereas, ZG destabilized the membranes at a temperature higher than 50 °C. In addition, the membrane-stabilizing effect of the carotenoids with the calcein-entrapped liposomes composed of lipids extracted from Thermus thermophilus were investigated. The addition of TZ resulted in stabilization of the membrane at all ranges of pH values. However, the addition of Z and ZG destabilized the membrane.  相似文献   
83.
The SnS activities in liquid Ag2S-SnS liquid mattes were obtained at 1100 °C and 1200 °C by the dew-point method. Negative deviations were observed, and the liquid matte solutions were modeled by the Wilson equations. Part of the liquid boundaries of the Ag2S-SnS phase diagram were derived from the model equations, yielding a eutectic temperature of 528 °C at x SnS=0.38. The phase diagram of the pseudobinary Ag2S-SnS was also verified experimentally by quenching samples equilibrated in evacuated and sealed silica capsules. Solubility limits of the components at the narrow-terminal solid-solution ranges were determined around the eutectic temperature. Within the Ag-Sn-S ternary system, the boundaries of the immiscibility region, together with the tie-line distributions, were established at 1200 °C. Activities of Ag, Sn, and S along the miscibility gap were calculated by utilizing the bounding binary thermodynamics, phase equilibria, and tie-lines.  相似文献   
84.
The effects of platinum addition to gold and indium addition to a gold-platinum alloy on their optical properties were investigated using a computer-controlled spectrophotometer. Spectral reflectance data from a polished sample for the incident CIE standard illuminant D65 was collected as a function of the wavelength at 10 nm intervals from 360 to 740 nm. Three coordinates,L* (lightness),a* (red-green),b* (yellow-blue), in the CIE 1976L*a*b* colour space, were determined to quantify the colour of experimental binary Au-Pt and ternary Au-Pt-In alloys. p ]The pronounced step near 520 nm (approximately 2.4 eV) in the spectral reflectance-wavelength curve for pure gold, which is responsible for the rich yellow colour of gold, became less pronounced with the addition of platinum. The decoloring effect of platinum was found to be due to this phenomenon. The addition of indium of up to ca 4 at% to a Au-10 at% Pt alloy increased both chromaticity indices, ie,a* andb* values, giving a gold tinge to the alloy: this effect was brought about by both the slight increase in reflectance in the long-wavelength range and the slight decrease in reflectance in the short-wavelength range of the visible spectrum.  相似文献   
85.
The boiler concept for combustion of large soya straw bales   总被引:2,自引:0,他引:2  
In one of the largest agricultural companies in Serbia, with over 2000 ha of soya plantations, there are 4000 t/year of baled soya straw produced. Soya straw biomass is planned to be used as a renewable energy source for heating the greenhouses, with 5 ha in area. Therefore, efforts have been made to develop a technology for utilizing large bales of soya straw for energy production. In the first phase, a demo energy production facility-furnace was developed and built. The facility had been tested in order to examine the quality of combustion of large soya straw bales. Since experimental results of testing of this facility have proved to be very satisfactory, in the second phase of the development, a hot water boiler of similar characteristics (burning soya straw bales, with dimensions 0.7×1.2×2.7 m3) has been designed.  相似文献   
86.
We are conducting a clinical study of the use of allogeneic polydactyly-derived chondrocyte sheets (PD sheets) for the repair of articular cartilage damage caused by osteoarthritis. However, the transplantation of PD sheets requires highly invasive surgery. To establish a less invasive treatment, we are currently developing injectable fragments of PD sheets (PD sheets-mini). Polydactyly-derived chondrocytes were seeded in RepCell™ or conventional temperature-responsive inserts and cultured. Cell counts and viability, histology, enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qPCR), and flow cytometry were used to characterize PD sheets-mini and PD sheets collected from each culture. To examine the effects of injection on cell viability, PD sheets-mini were tested in four experimental conditions: non-injection control, 18 gauge (G) needle, 23G needle, and syringe only. PD sheets-mini produced similar amounts of humoral factors as PD sheets. No histological differences were observed between PD sheets and PD sheets-mini. Except for COL2A1, expression of cartilage-related genes did not differ between the two types of PD sheet. No significant differences were observed between injection conditions. PD sheets-mini have characteristics that resemble PD sheets. The cell viability of PD sheets-mini was not significantly affected by needle gauge size. Intra-articular injection may be a feasible, less invasive method to transplant PD sheets-mini.  相似文献   
87.
In recent years, advances in drug therapy for head and neck squamous cell carcinoma (HNSCC) have progressed rapidly. In addition to cytotoxic anti-cancer agents such as platinum-based drug (cisplatin and carboplatin) and taxane-based drugs (docetaxel and paclitaxel), epidermal growth factor receptor-tyrosine kinase inhibitors (cetuximab) and immune checkpoint inhibitors such as anti-programmed cell death-1 (PD-1) antibodies (nivolumab and pembrolizumab) have come to be used. The importance of anti-cancer drug therapy is increasing year by year. Therefore, we summarize clinical trials of molecular targeted therapy and biomarkers in HNSCC from previous studies. Here we show the current trends and future prospects of molecular targeted therapy in HNSCC.  相似文献   
88.
Corrosion diagnosis of carbon steel in fresh water was carried out by electrochemical method and Mahalanobis-Taguchi (MT) method. The corrosion morphology of carbon steel was classified by the combination of i-E curve measurement and chronopotentiometry. The MT method is one of discriminant analysis and can diagnose distinction data by multiple causes, i.e., ion concentrations. In the present paper, the concept for the application of this method to corrosion diagnosis is introduced. Additionally, electrochemical method was used for specific classification of carbon steel corrosion. By comparing the results of electrochemical measurements with those of Mahalanobis distance, the utility of MT method in the corrosion diagnosis was discussed.  相似文献   
89.
Fluoroalkyl end-capped vinyltrimethoxysilane oligomer suffered the sol–gel reaction under alkaline conditions in the presence of titanium oxide nanoparticles in tetrahydrofuran to afford the corresponding fluorinated oligomer/titanium oxide nanocomposites[RF-(VM-SiO2)n-RF/TiO2] in excellent to moderate isolated yields. These fluorinated composites thus obtained were nanometer size-controlled fine particles, and exhibited good dispersibility and stability in traditional organic solvents except for water. These fluorinated nanocomposites were applied to the surface modification of glass to exhibit not only a completely superhydrophobic characteristic (a water contact angle: 180°) with a non-wetting property against water droplets but also a good oleophobicity imparted by fluoroalkyl segments in the composites on their surface. Of particular interest, we have found that the wettability for water can be switched between superhydrophobicity and superhydrophilicity by alternation of ultraviolet (UV) irradiation and dark storage with keeping a good oleophobicity on the modified surface treated with the anatase-type titanium oxide composite.  相似文献   
90.
This study investigates emotional display rules for seven basic emotions. The main goal was to compare emotional display rules of Canadians, US Americans, and Japanese across as well as within cultures regarding the specific emotion, the type of interaction partner, and gender. A total of 835 university students participated in the study. The results indicate that Japanese display rules permit the expression of powerful (anger, contempt, and disgust) significantly less than those of the two North American samples. Japanese also think that they should express positive emotions (happiness, surprise) significantly less than the Canadian sample. Furthermore, Japanese varied the display rules for different interaction partners more than the two North American samples did only for powerful emotions. Gender differences were similar across all three cultural groups. Men expressed powerful emotions more than women and women expressed powerless emotions (sadness, fear) and happiness more than men. Depending on the type of emotion and interaction partner some shared display rules occurred across culture and gender. The implications of these findings are discussed in relation to cultural dimensions and other cultural characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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