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991.
The nonindigenous mottled fingernail clam, Eupera cubensis is reported from the Upper Mississippi River Basin for the first time. This record represents a significant northern range expansion for the species in the United States. It appears to be presently confined to a 35-km stretch of the Chicago Sanitary and Ship Canal (CSSC), an artificial waterway that connects the Mississippi River drainage to the Great Lakes. Although the introduction of this species to the Great Lakes basin poses uncertain risks to the general aquatic community, the immediate effects of Eupera cubensis on the fauna of the CSSC are expected to be minimal.  相似文献   
992.
The transportability of Multisystemic Therapy (MST) for the treatment of juvenile offenders in a community-based context was examined in the current study. Results of this New Zealand study showed that significant pre- to posttreatment improvements occurred on most indicators of ultimate (i.e., offending behavior) and instrumental (i.e., youth compliance, family relations) treatment outcomes. Reductions in offending frequency and severity continued to improve across the 6- and 12-month follow-up intervals. In comparison to benchmarked studies, the current study demonstrated a more successful treatment completion rate. Additionally, overall treatment effect sizes were found to be clinically equivalent with the results of previous MST outcome studies with juvenile offenders and significantly greater than the effect sizes found in the control conditions. The findings of this evaluation add to the growing body of evidence that supports MST as an effective treatment for antisocial youth. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
This article reexamines the efficacy and endowment effects in public good (PG) dilemma by conceptualizing that efficacy = endowment × efficiency. Endowment is the resource that a person can contribute. Efficiency is the impact of a unit of endowment. Efficacy is the total impact of contribution. The authors used a group project scenario to simulate a continuous contribution PG dilemma. The 2 × 2 × 2 × 2 experimental design manipulated own efficiency and own endowment as within-subject variables and the other persons' efficiency and endowment as between-subject variables. Results indicate that cooperation was mainly affected by one's endowment and others' efficiency. The authors distinguished among 3 types of efficiency effects: (a) an own-absolute-efficiency effect that efficient people put in more effort regardless of others' efficiency, (b) an other-absolute-inefficiency effect that people put in more effort when others are inefficient, and (c) a relative-inefficiency effect that inefficient people put in less effort in the presence of efficient people. Contrasting previous robust findings on efficiency, they identified a situation in which efficiency has no effects--when one has more endowment than do others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
More than 3,000 individuals from 7 U.S. cities reported on their memories of learning of the terrorist attacks of September 11, as well as details about the attack, 1 week, 11 months, and/or 35 months after the assault. Some studies of flashbulb memories examining long-term retention show slowing in the rate of forgetting after a year, whereas others demonstrate accelerated forgetting. This article indicates that (a) the rate of forgetting for flashbulb memories and event memory (memory for details about the event itself) slows after a year, (b) the strong emotional reactions elicited by flashbulb events are remembered poorly, worse than nonemotional features such as where and from whom one learned of the attack, and (c) the content of flashbulb and event memories stabilizes after a year. The results are discussed in terms of community memory practices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
In this study, the authors examined the extent to which children’s self-regulation upon kindergarten entrance and classroom quality in kindergarten contributed to children’s adaptive classroom behavior. Children’s self-regulation was assessed using a direct assessment upon entrance into kindergarten. Classroom quality was measured on the basis of multiple classroom observations during the kindergarten year. Children’s adaptive classroom behavior in kindergarten was assessed through teacher report and classroom observations: Teachers rated children’s cognitive and behavioral self-control and work habits during the spring of the kindergarten year; observers rated children’s engagement and measured off-task behavior at 2-month intervals from November to May. Hierarchical linear models revealed that children’s self-regulation upon school entry in a direct assessment related to teachers’ report of behavioral self-control, cognitive self-control, and work habits in the spring of the kindergarten year. Classroom quality, particularly teachers’ effective classroom management, was linked to children’s greater behavioral and cognitive self-control, children’s higher behavioral engagement, and less time spent off-task in the classroom. Classroom quality did not moderate the relation between children’s self-regulation upon school entry and children’s adaptive classroom behaviors in kindergarten. The discussion considers the implications of classroom management for supporting children’s early development of behavioral skills that are important in school settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
Improving mathematics and science education in the United States has been a matter of national concern for over half a century. Psychology has a vital role to play in this enterprise. In this article, the authors review the kinds of contributions that psychology can make in four areas: (a) early understanding of mathematics, (b) understanding of science, (c) social and motivational aspects of involvement in mathematics and science, and (d) assessment of learning in mathematics and science. They also examine challenges to psychology’s playing a central and constructive role and make recommendations for overcoming those challenges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
The potential association between psychosis and violence to others has long been debated. Past research findings are mixed and appear to depend on numerous potential moderators. As such, the authors conducted a quantitative review (meta-analysis) of research on the association between psychosis and violence. A total of 885 effect sizes (odds ratios) were calculated or estimated from 204 studies on the basis of 166 independent data sets. The central tendency (median) of the effect sizes indicated that psychosis was significantly associated with a 49%–68% increase in the odds of violence. However, there was substantial dispersion among effect sizes. Moderation analyses indicated that the dispersion was attributable in part to methodological factors, such as study design (e.g., community vs. institutional samples), definition and measurement of psychosis (e.g., diagnostic vs. symptom-level measurement, type of symptom), and comparison group (e.g., psychosis compared with externalizing vs. internalizing vs. no mental disorder). The authors discuss these findings in light of potential causal models of the association between psychosis and violence, the role of psychosis in violence risk assessment and management, and recommendations for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Bringing together a number of design celebrities, among them Greg Lynn, UN Studio, Foreign Office Architects (FOA) and Kevin Kennon Architect, United Architects (UA) was established to create a collaborative proposal for the 2003 competition for a new World Trade Center. Invoking the name as well as the intentions of what started as a similar collaborative formation by established actors and film-makers in the 1940s (United Artists) to challenge mainstream corporate power, UA attempted to offer more visionary alternatives to the expectations of typical mainstream architectural solutions. Kevin Kennon here presents an insider's perspective on the UA collaboration and employs his unique history, including his former partnership at Kohn Pedersen Fox (KPF) to raise important questions about collective design in terms of authorship, identity and practice. Central to his observations are the differences between the efficiency models of corporate teams and truly collaborative endeavours. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
999.
Stream quality in a small urbanised catchment   总被引:1,自引:0,他引:1  
River-length patterns in the chemistry and biology of the Charlton Brook, an unclassified watercourse in Sheffield, England, have been examined. Five sampling sites for macroinvertebrates and pollutant analysis were used, in conjunction with Environment Agency's General Quality Assessment (GQA) methodologies and hydraulic analysis of the catchment. Sites were strategically located to account for the tributaries and the brook downstream of their confluence, to assess the potential impact from surface water outfalls (SWOs). Variations in GQA parameters indicate a significant drop in quality downstream of the SWOs that discharge to the study watercourse, with a marked drop in biological diversity noted at the onset of urbanisation. The decline in biological quality however is greater than that suggested by physicochemical analysis alone. There was a significant inverse relationship between impermeable area and biological diversity. Analysis of polycyclic aromatic hydrocarbons (PAHs) and trace metals in sediment from the watercourse showed significant yet irregular variations between sites. The potential toxicity of instream metal concentrations was determined using cumulative criterion unit (CCU) scores, which highlighted cadmium, copper and lead as the major sources of potential chronic instream toxicity. The threshold for likely harm to aquatic life is exceeded at all sites. In the absence of different physical characteristics, comparisons of the chemical and biological data indicate that the benthic macroinvertebrate population of such watercourses are adversely affected by the stormwater inputs.  相似文献   
1000.
Integrated understanding of urban land, groundwater (shallow and deep), baseflow and surface-water quality relationships is required for effective urban water-quality management. Chemical quality data from across these media have been collected for the Birmingham (UK) aquifer--River Tame conurbation to assess chemical transport from contaminated land to groundwater to baseflow to surface water. Although metals concentrations were high in soils, low leachability and attenuation caused concentrations in groundwaters and baseflow discharging to surface water to be generally low with only sporadic elevated concentrations attributed to localised point sources. Hydrocarbon VOCs (volatile organic compounds) were similarly absent or at low concentration attributable to their ready natural attenuation. Chlorinated VOCs, however, were widely encountered in groundwater, discharging as baseflow to surface water and impacting surface-water quality. This is attributed to their DNAPL (dense nonaqueous-phase liquid) properties and relative recalcitrance although there was some evidence of biodegradation, albeit insufficient to protect surface water and groundwater abstraction receptors. Some inorganic trends were evident across the various media; nitrate was the most significant quality concern. Generic conclusions are drawn on urban water-quality management and the need for risk-based management strategies to optimise use of urban, sporadically contaminated groundwater in conjunction with surface water highlighted.  相似文献   
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