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141.
Argues that the debate about sexism in Diagnostic and Statistical Manual of Mental Disorders (DSM-III) is misdirected and probably involves a social artifact rather than a true labeling problem. Men who are troubled are more likely to act out in antisocial ways, while women are more likely to turn problems inward. We are more likely to label women who cannot adapt as sick and men who cannot adapt as criminal, but both groups are out of step with the social system and are being pressured to make behavioral changes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
142.
Septic systems can present a risk to human health by releasing highly soluble nitrate–nitrogen into the groundwater. A research and demonstration study undertaken in Black River Falls, Wisconsin, evaluated several promising biofilter technologies for on-site nitrogen removal. Duplicate recirculating sand filter-upflow anaerobic systems with a design hydraulic loading rate of 954?L/day (250?gal/day) were used to treat septic tank effluent from a correctional institution and produced a treated wastewater with a total nitrogen concentration of 15.2?mg/L for System 1 and 18.2?mg/L for System 2, or 72.0 and 63.0% nitrogen removal, respectively. The differences between the two systems appear to have been the result of process configuration changes made over the duration of the study. This paper evaluates the nitrogen removal performance of the recirculating sand filter-upflow anaerobic systems and the effect of operational and environmental factors, including the recirculation ratio, BOD5/NO3?, and temperature. Nitrogen removal was limited by the recirculation ratio with the maximum total nitrogen removal of 70.1% when the recirculation ratio = 3. Improved performance was also noted for temperatures ≥ 20°C and BOD5/NO3? ≥ 8. Low temperatures adversely affected nitrification and low BOD5/NO3? adversely affected denitrification. The relationships among nitrogen removal, recirculation ratio, BOD5/NO3?, and temperature are also discussed.  相似文献   
143.
A synthetic Candida antarctica lipase B (CALB) gene open reading frame (ORF) for expression in yeast was constructed, and the lycotoxin-1 (Lyt-1) C3 variant gene ORF, potentially to improve the availability of the active enzyme at the surface of the yeast cell, was added in frame with the CALB ORF using an automated PCR assembly and DNA purification protocol on an integrated robotic workcell. Saccharomyces cerevisiae strains expressing CALB protein or CALB Lyt-1 fusion protein were first grown on 2% (w/v) glucose, producing 9.3 g/L ethanol during fermentation. The carbon source was switched to galactose for GAL1-driven expression, and the CALB and CALB Lyt-1 enzymes expressed were tested for fatty acid ethyl ester (biodiesel) production. The synthetic enzymes catalyzed the formation of fatty acid ethyl esters from ethanol and either corn or soybean oil. It was further demonstrated that a one-step-charging resin, specifically selected for binding to lipase, was capable of covalent attachment of the CALB Lyt-1 enzyme, and that the resin-bound enzyme catalyzed the production of biodiesel. High-level expression of lipase in an ethanologenic yeast strain has the potential to increase the profitability of an integrated biorefinery by combining bioethanol production with coproduction of a low-cost biocatalyst that converts corn oil to biodiesel.  相似文献   
144.
Emerging disease modifying therapeutic strategies for Alzheimer's disease (AD) have generated a critical need for biomarkers of early stage disease. Here, we describe the identification and assessment of a number of candidate biomarkers in patients with mild to moderate probable AD. Plasma from 47 probable Alzheimer's patients and 47 matched controls were analysed by proteomics to define a significant number of proteins whose expression appeared to be associated with AD. These were compared to a similar proteomic comparison of a mouse transgenic model of amyloidosis, which showed encouraging overlap with the human data. From these studies a prioritised list of 31 proteins were then analysed by immunoassay and/or functional assay in the same human cohort to verify the changes observed. Eight proteins continued to show significance by either immunoassay or functional assay in the human plasma and these were tested in a further set of 100 probable AD patients and 100 controls from the original cohort. From our data it appeared that two proteins, serpin F1 (pigment epithelium-derived factor) and complement C1 inhibitor are down-regulated in plasma from AD patients.  相似文献   
145.
Summary X-ray diffraction patterns at room temperature for soaps of barium, calcium, and lithium were found to be characteristic for different soaps of the same cation. This is true not only for palmitates and stearates but also (with minor variations) for mixed soaps containing up to at least 50% oleate, for pure calcium oleate, and even for lithium 12-hydroxystearate. Soaps of the same cation in mixtures approximating the composition of natural tallow fatty acids appear to form mixed crystals. The succession of phases formed on heating shows strongly the influence of the oleate in the mixture. Calcium resinates appear to crystallize imperfectly but definitely with a “head to head” arrangment of the abietate radicals in contrast to the acids which give evidence of a head to tail arrangement. This research was carried out as part of a project, “Phase Studies of Greases”, supported by the office of Naval Research; Contract Number N6onr-238-TO-2, NRO57057. Contribution from the Depatment of Chemistry, University of Southern California.  相似文献   
146.
Heterogeneous accumulation of uranium in the brain of rats   总被引:1,自引:0,他引:1  
Recent reports suggest that uranium can accumulate not only in known target organs, that is, kidneys or bones, but also in others such as central nervous system. In the present work, the accumulation of uranium in the brain of rats was studied after repeated exposure by inhalation, chronic exposure by ingestion and acute exposure by injection. For each route of administration, the amount of uranium entering the brain was low. The results showed different accumulation in the brain areas according to the route of intake. Injection gave a rather homogeneous distribution in the different brain areas, whereas both inhalation and ingestion yielded heterogeneous but specific accumulation. These differences in distribution suggest the operation of different mechanisms of delivery of uranium to the brain tissues.  相似文献   
147.
148.
Friction is able to induce major consequences on surface polymer properties (wear, scratch, etc.). These problems are crucial in the case of organic coatings (paints, varnish). The aim of this work is to analyse the influence of friction on the nano-wear behaviour of polystyrene. Studies will be focused on the analysis of the transfer layer induced by the friction of a polystyrene cylinder in contact with a flat and smooth substrate. The model substrate is a hydrophilic silicon wafer (hydroxylated by a piranha treatment). Friction experiments are performed with a translation tribometer which measures the tangential force between the polymer and the substrate for controlled normal force and friction speed. The transfer layer is analysed using atomic force microscopy (AFM). Tentative correlations between transfer layer characteristics and polymer properties are proposed.  相似文献   
149.
Modeling the influence of vegetation and water pond on urban microclimate   总被引:4,自引:0,他引:4  
The beneficial influence of trees and water ponds on summer comfort in urban spaces was studied experimentally in situ and in wind tunnels but the modeling needs further development to become effective in practical applications. This paper introduces a numerical approach based on coupling the CFD model of airflow, in which the influence of trees is considered as source terms, and the radiation exchange, completed with thermal conduction. The CFD, radiation and thermal conduction models use the same discretization grid at their common boundaries. The model was used to estimate the influence of trees and water ponds in a real town square. Comparison of results between two situations, with and without vegetation and water pond, indicate that surface temperatures are reduced in presence of trees and the comfort is improved.  相似文献   
150.
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