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141.
The present study examined the effects of executive function (i.e., EF) and anger/hostility on the relationship between stress (across individual stress domains, as well as at the aggregate level) and aggression. Two independent groups of participants—a college sample and a low-income community sample—were administered a battery of self-report measures concerning the subjective experience of stress, aggressive behaviors, and feelings of state anger and hostility in the last month, along with a battery of well-validated neuropsychological tests of EF. Across both samples, the stress domains that demonstrated the strongest associations with aggression were those involving chronic strains of daily living (e.g., job, financial, health) versus interpersonal stressors (e.g., family, romantic). In the community sample, analyses also revealed a significant interaction between perceived stress (aggregated across domains) and EF in predicting aggressive behavior. Specifically, participants with relatively low EF abilities, across different EF processes, showed a stronger relationship between different domains of stress and aggression in the last month. Similar effects were demonstrated in the college sample, although the interaction was not significant. In both samples, experiences of anger and hostility in the last month mediated the relationship between perceived stress (aggregate) and aggressive behavior among those low, but not high, in EF. These findings highlight the importance of higher-order cognitive processes in regulating appropriate affective and behavioral responses across different types of individuals, particularly among those experiencing high levels of stress. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
142.
A novel scanning probe microscope stage permits break junction measurements of single molecule conductance while the molecules are illuminated with visible light. We studied a porphyrin-fullerene dyad molecule designed to form a charge separated state on illumination. A significant fraction of illuminated molecules become more conductive, returning to a lower conductance in the dark, suggesting the formation of a long-lived charge separated state on the indium-tin oxide surface. Transient absorption spectra of these molecular layers are consistent with formation of a long-lived charge separated state, a finding with implications for the design of molecular photovoltaic devices.  相似文献   
143.
What the public thinks about the tobacco industry and its products   总被引:1,自引:0,他引:1  
Objectives: To assess public attitudes toward the tobacco industry and its products, and to identify predictors of attitudes supportive of tobacco industry denormalisation.

Design: Population based, cross sectional survey.

Setting: Ontario, Canada.

Subjects: Adult population (n = 1607).

Main outcome measures: Eight different facets of tobacco industry denormalisation were assessed. A denormalisation scale was developed to examine predictors of attitudes supportive of tobacco industry denormalisation, using bivariate and multivariate analyses.

Results: Attitudes to the eight facets of tobacco industry denormalisation varied widely. More than half of the respondents supported regulating tobacco as a hazardous product, fining the tobacco industry for earnings from underage smoking, and suing tobacco companies for health care costs caused by tobacco. Majorities also thought that the tobacco industry is dishonest and that cigarettes are too dangerous to be sold at all. Fewer than half of the respondents thought that the tobacco industry is mostly or completely responsible for the health problems smokers have because of smoking and that tobacco companies should be sued for taxes lost from smuggling. In particular, less than a quarter thought that the tobacco industry is most responsible for young people starting to smoke. Non-smoking, knowledge about health effects caused by tobacco, and support for the role of government in health promotion were independent predictors of support for tobacco industry denormalisation.

Conclusions: Although Ontarians are ambivalent toward tobacco industry denormalisation, they are supportive of some measures. Mass media programmes aimed at increasing support for tobacco industry denormalisation and continued monitoring of public attitudes toward this strategy are needed.

  相似文献   
144.
Phospholipids self-assemble in bulk oils to form structures such as reverse micelles that can alter the microenvironment where chemical degradation reactions occur, such as lipid oxidation. In this study, we examined the influence of phospholipid reverse micelles on the activity of non-polar (α-tocopherol) and polar (Trolox) antioxidants in stripped soybean oil (SSO). Reverse micelles were formed by adding 1000 μM 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) to SSO. The addition of DOPC reverse micelles had a prooxidant effect, shortening the lag phase of SSO at 55 °C. DOPC improved the activity of low α-tocopherol or Trolox concentrations (10 μM) but decreased the activity of high concentrations (100 μM). Hydrophilic Trolox had better antioxidant activity than hydrophobic α-tocopherol. Fluorescence steady state and lifetime decay studies suggests that differences in the antioxidant activity of Trolox and α-tocopherol could be due to differences in their physical location in DOPC reverse micelles. These results will improve our understanding and control of lipid oxidation in bulk oils.  相似文献   
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147.
The condition number of a matrix is commonly used for investigating the stability of solutions to linear algebraic systems. Recent meshless techniques for solving partial differential equations have been known to give rise to ill-conditioned matrices, yet are still able to produce results that are close to machine accuracy. In this work, we consider the method of fundamental solutions (MFS), which is known to solve, with extremely high accuracy, certain partial differential equations, namely those for which a fundamental solution is known. To investigate the applicability of the MFS, either when the boundary is not analytic or when the boundary data are not harmonic, we examine the relationship between its accuracy and the effective condition number.Three numerical examples are presented in which various boundary value problems for the Laplace equation are solved. We show that the effective condition number, which estimates system stability with the right-hand side vector taken into account, is roughly inversely proportional to the maximum error in the numerical approximation. Unlike the proven theories in literature, we focus on cases when the boundary and the data are not analytic. The effective condition number numerically provides an estimate of the quality of the MFS solution without any knowledge of the exact solution and allows the user to decide whether the MFS is, in fact, an appropriate method for a given problem, or what is the appropriate formulation of the given problem.  相似文献   
148.
Type 2 diabetes may be associated with exacerbated aging-related declines in cognitive neuropsychological performance. The authors examined whether such effects are systematic (i.e., broadly distributed across domains or domain-specific) or moderated by age (i.e., varying across age within older adults). The authors assembled recent cross-sectional data from the Victoria Longitudinal Study (VLS) Sample 3 (Wave 1; initial n = 570; initial age = 53-90 years). Using a comprehensive, multidimensional spectrum of cognitive neuropsychological tests, the authors examined performance differences by diabetes status (diabetes group vs. healthy controls) and age (young-old vs. old-old). Our results showed that healthy controls significantly outperformed the diabetes group only on markers of executive functioning and speed. Notably, the diabetes-related effects were robust across the two late-life age groups. Future research examining longitudinal changes is recommended. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
149.
Starting from our previously reported hit, a series of 1,5-diaryl-1,2,3-triazole-4-carbohydrazones were synthesized and evaluated as inhibitors of the YAP/TAZ-TEAD complex. Their binding to hTEAD2 was confirmed by nanodifferential scanning fluorimetry, and some of the compounds were also found to moderately disrupt the YAP-TEAD interaction, as assessed by a fluorescence polarization assay. A TEAD luciferase gene reporter assay performed in HEK293T cells and RTqPCR measurements in MDA-MB231 cells showed that these compounds inhibit YAP/TAZ-TEAD activity to cells in the micromolar range. In spite of the cytotoxic effects displayed by some of the compounds of this series, they are still good starting points and can be suitably modified into an effective and viable YAP-TEAD disruptor in the future.  相似文献   
150.
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