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71.
The present study aimed to assess the correlation between food and fatty acid (FA) intake and the serum phospholipid (PL) FA status in European adolescents and explored the percentage of variation in serum PL FA that could be attributed to dietary habits. Participants included 528 adolescents recruited in the HELENA Study. Dietary intake was assessed by two, self-administered, non-consecutive 24-h recalls. PL FA concentrations were measured in fasting venous serum samples. Reduced rank regressions were applied to examine the combined effect of food intakes. Results indicated that the variance in serum PL FA in adolescents, that could be explained by diet varied from 7.0 % for MUFA to 14.2 % for n-3FA. The variance in the long-chain n-3FA was mainly explained by fish intake but also by coffee and tea consumption. In conclusion this study indicated that dietary intake influences the serum PL FA status to a limited amount but that also other factors interfere. However, dietary intake is important as it is among those factors that could be modified. Furthermore, the results suggest that the overall dietary habits should be considered instead of only the consumption of single foods or nutrients, as the medium of the food or concomitant intake of foods and nutrients might interact and as such influence absorption or metabolism.  相似文献   
72.
Angle-resolved light scattering has been used for decades to quantify the surface roughness of optical components. However, because this technique is affected by the contribution of both interfaces of the sample, it cannot be applied to transparent substrates. We show how to overcome this issue and apply these principles to the characterization of superpolished samples.  相似文献   
73.
Adaptive wear-resistant coatings produced by physical vapor deposition (PVD) are a relatively new generation of coatings which are attracting attention in the development of nanostructured materials for extreme tribological applications. An excellent example of such extreme operating conditions is high performance machining of hard-to-cut materials. The adaptive characteristics of such coatings develop fully during interaction with the severe environment. Modern adaptive coatings could be regarded as hierarchical surface-engineered nanostructural materials. They exhibit dynamic hierarchy on two major structural scales: (a) nanoscale surface layers of protective tribofilms generated during friction and (b) an underlying nano/microscaled layer. The tribofilms are responsible for some critical nanoscale effects that strongly impact the wear resistance of adaptive coatings. A new direction in nanomaterial research is discussed: compositional and microstructural optimization of the dynamically regenerating nanoscaled tribofilms on the surface of the adaptive coatings during friction. In this review we demonstrate the correlation between the microstructure, physical, chemical and micromechanical properties of hard coatings in their dynamic interaction (adaptation) with environment and the involvement of complex natural processes associated with self-organization during friction. Major physical, chemical and mechanical characteristics of the adaptive coating, which play a significant role in its operating properties, such as enhanced mass transfer, and the ability of the layer to provide dissipation and accumulation of frictional energy during operation are presented as well. Strategies for adaptive nanostructural coating design that enhance beneficial natural processes are outlined. The coatings exhibit emergent behavior during operation when their improved features work as a whole. In this way, as higher-ordered systems, they achieve multifunctionality and high wear resistance under extreme tribological conditions.  相似文献   
74.
See you later amyloid β : A screen of a small library of oxime oligomers with an HTS fluorescence assay for amyloid fibril inhibition and subsequent investigation by atomic force microscopy revealed two new micromolar inhibitors of amyloid fibril formation. These new inhibitors have IC50 values in the 10 μM range.

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75.
项目地点:摩洛哥伊尔富德项目类型:建筑(住宅)开工日期:2006年元月该项目获2005年豪瑞可持续建筑大奖赛非洲中东地区提名奖  相似文献   
76.
The present study used a prospective design to test the role of involuntary subordination as a predictor of major depression. Involuntary subordination is a construct derived from social rank theory and has been implicated as a cause of major depression. Its most salient features include feelings of entrapment and unfavourable social comparisons (i.e., low perceived status). An initial sample of 146 graduate students underwent a diagnostic interview to confirm a history of major depression and also completed measures of entrapment and social comparison. After 16 months, participants were assessed for a recurrence of major depression. Participants who experienced a recurrence of depression had significantly higher levels of involuntary subordination (as measured by factor scores of entrapment and social comparison). A logistic regression analysis also showed that involuntary subordination predicted recurrence of depression, even when controlling for current major depression and the number of previous episodes. The present study demonstrates the advantages of adopting a social rank perspective in modeling major depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
The enormous amount of information available on the Internet requires the use of search engines in order to find specific information. As far as web accessibility is concerned, search engines contain two kinds of barriers: on the one hand, the interfaces for making queries and accessing results are not always accessible; on the other hand, web accessibility is not taken into account in information retrieval (IR) processes. Consequently, in addition to interface problems, accessing the items in the list of results tends to be an unsatisfactory experience for people with disabilities. Some groups of users cannot take advantage of the services provided by search engines, as the results are not useful due to their accessibility restrictions. The goal of this paper is to propose the integration of web accessibility measurement into information retrieval processes. Firstly, quantitative accessibility metrics are defined in order to accurately measure the accessibility level of web pages. Secondly, a model to integrate these metrics within IR processes is proposed. Finally, a prototype search engine which re-ranks results according to their accessibility level based on the proposed model is described.  相似文献   
78.
While automatic tools are not intended to replace human judgment, they are crucial in order to develop accessible websites. The release of WCAG 2.0 has caused great expectation, as it is supposed to be precisely testable with automated review tools. Therefore, more effective tools could be developed. However, so far few tools applying WCAG 2.0 have been developed. This paper presents an evaluation framework which has been updated in order to evaluate the new tests. In addition, it describes a validation process carried out in order to verify the effectiveness of the new version of the evaluation tool. The effectiveness is validated by conducting a quantitative and qualitative analysis of the results obtained by applying both versions of the tool (the one implementing WCAG 1.0 and the one implementing WCAG 2.0) to a set of selected web pages, as well as by manual evaluation of an expert for detecting the possible false positives and false negatives produced by each tool.  相似文献   
79.
Lauric acid hydroxylation and aminopyrineN-demethylation were studied in kidney and liver microsomes from rats treated with fish oil. Different doses of fish oil containing 20% eicosapentaenoic acid and 10% docosahexaenoic acid were provided daily to the rats for seven days. In all the groups studied, the lauric acid metabolism was higher in kidney microsomes and the aminopyrine metabolism in the liver microsomes. Although no effect on the renal cytochrome P-450 concentration was detectable, all four fish oil doses increased the hepatic concentration of cytochrome P-450 by a mean 27%. The higher fish oil doses used increased the renal and hepatic microsomal metabolism of aminopyrine. The lauric acid metabolism was increased by fish oil only in the liver. Fish oil, a known inducer of fatty acid peroxisomal β-oxidation, also induced microsomal activity. These results show that liver and kidney respond in different ways to dietary factors such as fish oil. In addition, our study would suggest that fish oil increased the activity of two different families of liver cytochrome P-450. The activity of kidney lauric acid 11- and 12-hydroxylation, however, was not modulated by fish oil.  相似文献   
80.
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