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181.
The subject of the present study is to highlight the use of clay waste resulting from the operations of aggregate quarries through developing lightened clayey concretes. The lightening is achieved by adding wood aggregates, which are waste materials from woodworking activities. The authors account for the influence of components on the mechanical characteristics of hardened concretes and on the behaviour of the material just after mixing. They propose a formulation allowing the development a dry material with a volumic weight equal to 800 kg/m3 and a compressive strength, at hydrous stability, equal to 2.5 MPa offering the possibility tof being poured easily. Attempts at treating wood aggregates have proved the necessity for a systematic study to take into account the specificity of clay.  相似文献   
182.
The pathophysiology of cardiovascular diseases is complex and may involve oxidative stress-related pathways. Eriodictyol is a flavonoid present in citrus fruits that demonstrates anti-inflammatory, anti-cancer, neurotrophic, and antioxidant effects in a range of pathophysiological conditions including vascular diseases. Because oxidative stress plays a key role in the pathogenesis of cardiovascular disease, the present study was designed to verify whether eriodictyol has therapeutic potential. Upregulation of heme oxygenase-1 (HO-1), a phase II detoxifying enzyme, in endothelial cells is considered to be helpful in cardiovascular disease. In this study, human umbilical vein endothelial cells (HUVECs) treated with eriodictyol showed the upregulation of HO-1 through extracellular-regulated kinase (ERK)/nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathways. Further, eriodictyol treatment provided protection against hydrogen peroxide-provoked cell death. This protective effect was eliminated by treatment with a specific inhibitor of HO-1 and RNA interference-mediated knockdown of HO-1 expression. These data demonstrate that eriodictyol induces ERK/Nrf2/ARE-mediated HO-1 upregulation in human endothelial cells, which is directly associated with its vascular protection against oxidative stress-related endothelial injury, and propose that targeting the upregulation of HO-1 is a promising approach for therapeutic intervention in cardiovascular disease.  相似文献   
183.
Parallel processing and double‐flow methods, which are used to increase the speed of turbo‐code decoding, cause memory contentions. Although memory contentions due to parallel processing can be resolved by adopting the quadratic polynomial permutation (QPP) interleaver, the double‐flow method still causes memory contentions because of its read/write sequences from both ends of the input packets. Thus, we propose a modified architecture to resolve memory contentions for the double‐flow method to fit the QPP interleaver. In our experiment, the proposed method has a shorter decoding time and smaller hardware size compared the conventional method. A bit‐accurate simulation was performed, and hardware implementation with field‐programmable gate arrays (FPGAs) led to a high throughput of 80 Mbps. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
184.
The self-heating of strained-silicon MOSFETs is demonstrated experimentally. Output characteristics measured by a pulse technique, in which self-heating is absent, show as much as 15% greater drain current (for 15% Ge content) than the corresponding static measurements. Comparison of the current measured this way with the static measurements allows an estimate of the channel temperature during the static operation. The temperature rise is compared to a simple estimate of the thermal resistance of the FET  相似文献   
185.
Estrogen metabolism in the human intestine was studied in two ways. Firstly, by measuring the excretion of 12 estrogens in pooled human late pregnancy feces before and during the administration of ampicillin (2 g/day). Secondly, by administering 5.4 and 20 mg of 16alpha-hydroxyestrone orally to two postmenopausal women and analyzing the estrogens in simultaneously drawn portal and peripheral venous blood samples at time intervals from 0 to 150 min after steroid administration. The majority of the estrogens in normal pregnancy feces were unconjugated. The amounts of estradiol, estreon and 16-epiestriol excreted, relative to the principal estrogen estriol, were greater than in pregnancy bile or urine and 16alpha-hydroxyestrone, an important biliary estrogen, was only present in trace amounts. Considerable quantities of 15alpha-hydroxyestradiol-17beta were also found. Ampicillin administration, which decreases intestinal bacterial steroid metabolism, caused a huge increase in the fecal excretion of conjugated estrogens. In particular it caused very striking increases in the excretion of both unconjugated and conjugated, estriol, 15alpha-hydroxyestrone, 15alpha-hydroxyestradiol and 2-methoxyestrone. These findings emphasize the active role played by the intestinal microflora in estrogen metabolism under normal conditions. Administration of 16alpha-hydroxyestrone resulted in increases in portal venous unconjugated and conjugated 16alpha-hydroxyestrone, 16-oxoestradiol-17beta, 15alpha-hydroxyestrone, 16-epiestriol and conjugated estriol levels. The most significant finding in both subjects was the large increase in portal venous unconjugated 15alpha-hydroxyestrone. This would suggest that the human intestine (or intestinal contents) has the ability to carry out the transformation, 16alpha-hydroxyestrone leads to 15alpha-hydroxyestrone. Increases in the same estrogens were found in peripheral plasma, with the increase in conjugated estriol occurring in peripheral blood before it was seen in portal blood. The largest elevations in peripheral plasma values were seen in unconjugated estriol and conjugated 16alpha-hydroxyestrone in the subject who received the 20 mg dose and in unconjugated 16alpha-hydroxyestrone and 16-oxoestradiol-17beta in the subject who had the 5.4 mg dose. The intestinal and enterohepatic metabolism of estrogens is discussed in relation to these findings.  相似文献   
186.
187.
Psychophysiological research failed to establish consistent physiological patterns differentiating emotion. Recent data showed that people verbally report experiencing peripheral changes that differ among emotions. The present studies tested the hypothesis that these reports originate in social schemata. Study 1 showed that Ss' reports of peripheral changes experienced during actual emotion do not differ from those defined in social schemata. Studies 2 and 3 showed that these schemata are similar across cultures. Overall, these data suggest that (a) people can directly access schemata about peripheral changes in emotion, (b) people are likely to do so when they believe to be reporting actual memories of such changes, and (c) the specific patterns revealed by past research may reflect prototypical knowledge of emotion. Finally, the data highlight the various peripheral patterns as they exist in schematic knowledge of emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
188.
Word Sense Disambiguation Using the Classification Information Model   总被引:1,自引:0,他引:1  
A Classification Information Model is a pattern classification model.The model decides the proper class of an input instance by integrating individual decisions, each of which is made with each feature in the pattern.Each individual decision is weighted according to the distributional property of the feature deriving the decision. An individual decision and its weight are represented as classification information which is extracted from the training instances.In the word sense disambiguation based on the model, the proper sense of an input instance is determined by the weighted sum of whole individual decisions derived from the features contained in the instance.  相似文献   
189.
Indoor ultrafine particles (UFP, <100 nm) undergo aerosol processes such as coagulation and deposition, which alter UFP size distribution and accordingly the level of exposure to UFP of different sizes. This study investigates the decay of indoor UFP originated from five different sources: a gas stove and an electric stove, a candle, a hair dryer, and power tools in a residential test building. An indoor aerosol model was developed to investigate differential effects of coagulation, deposition, and ventilation. The coagulation model includes Brownian, van der Waals, and viscosity forces, and also fractal geometry for particles of >24 nm. The model was parameterized using different values of the Hamaker constant for predicting the coagulation rate. Deposition was determined for two different conditions: central fan on versus central fan off. For the case of a central fan running, deposition rates were measured by using a nonlinear solution to the mass balance equation for the whole building. For the central fan off case, an empirical model was used to estimate deposition rates. Ventilation was measured continuously using an automated tracer gas injection and sampling system. The study results show that coagulation is a significant aerosol process for UFP dynamics and the primary cause for the shift of particle size distribution following an episodic high-concentration UFP release with no fans operating. However, with the central mechanical fan on, UFP deposition loss is substantial and comparable to the coagulation loss. These results suggest that coagulation should be considered during high concentration periods (>20,000 cm?3), while particle deposition should be treated as a major loss mechanism when air recirculates through ductwork or mechanical systems.

Copyright 2012 American Association for Aerosol Research  相似文献   
190.
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