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221.
Species that cannot adapt or keep pace with a changing climate are likely to need human intervention to shift to more suitable climates. While hundreds of articles mention using translocation as a climate-change adaptation tool, in practice, assisted migration as a conservation action remains rare, especially for animals. This is likely due to concern over introducing species to places where they may become invasive. However, there are other barriers to consider, such as time-frame mismatch, sociopolitical, knowledge and uncertainty barriers to conservationists adopting assisted migration as a go-to strategy. We recommend the following to advance assisted migration as a conservation tool: attempt assisted migrations at small scales, translocate species with little invasion risk, adopt robust monitoring protocols that trigger an active response, and promote political and public support.  相似文献   
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Experiments are reported in which three prochiral organic reactions were conducted in the presence of a ca. 1T magnetic field which was oriented with reference to the earth's geometric axes. The sign and magnitude of the rotation varied with the macroscopic orientation of the magnetic field and the time that the reaction was performed. Control measurements were in accord with expectations. The fact that the sign of the observed optical rotation of the product was reversed for all three reported reactions when the magnetic field was reversed for reactions conducted on the same day suggests that either the observed asymmetric synthesis was due to the reactions being conducted in a chiral physical field or extremely unusual stochastic processes were involved.  相似文献   
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Research over the last 25 years on the contribution of aloneness to creativity enhancement has had mixed results. Early studies of sensory deprivation generally found negative effects while more recent research on flotation isolation has reported positive influence. Sports performance, for example, has been improved by means of directed imagery and flotation aloneness. However, there has been only one study which has attempted to enhance creativity through the flotation method and while this study reported positive results, it lacked several control features and was based on a very small sample of highly selected subjects.The present study was designed to evaluate directly the potential contribution of floating to creativity enhancement as measured by the Guilford fluency test and other measures. Subjects were male and female university students, half of whom spent one hour in a float environment and the other half in a darkened room. Each was tested before and after experimental trial on the Guilford and other creativity measures and on two personality/affect scales. Float subjects showed significant increases on the Guilford test from the pre- to post-float and meaningful increases on other thinking measures as compared to non-floating control subjects. Floating was associated with a decrease in anxiety/tension, depression, hostility, and fatigue, but with an increase in vigor and a maintenance of curiosity scores, and it is speculated that the creativity benefits may be a result of these state changes.  相似文献   
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The paper identifies some of the main ethical issues concerning the protection of the environment from radiation and suggests ways in which ethics can aid in developing a system of protection. After a presentation of background on ethical theory and environmental ethics, three main issues related to environmental protection are discussed: First, the question of valuing the environment and implications for the definition of harm and monetary valuation of environmental goods; second, difficulties with scientific uncertainty and applications of the precautionary principle; and third, issues concerned with the distribution of risk and its relevance for participation in decision-making. In summary, the paper argues that there are strong ethical grounds to provide for the protection of the environment and that, all other things being equal, there is no reason to treat ionising radiation differently to other environmental stressors.  相似文献   
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In understanding the safety climate or culture of a workplace, the perceptions and attitudes of the workforce are important factors in assessing safety needs. Safety solutions may fail if they do not take into account these prevailing attitudes and perceptions. Also, changes in attitudes and perceptions about safety are often likely outcomes of safety interventions. The aim of this study was to develop a measure of perception and attitudes about safety as an indicator of safety culture for use with working populations. After reviewing the structure and content of a number of older, related measures of safety attitudes, a 67-item questionnaire was developed. The questionnaire was distributed in a self-administered form to 1560 workers in a wide variety of types of jobs and 660 questionnaires were returned from 7 workplaces with a response rate of 42%. Items were evaluated by Cronbach alpha which showed that the item set shared considerable common variance. Scale development was approached in two ways. First items which were highly skewed were removed, resulting in removal of around half of the items, with very little loss in alpha. The remaining items were then subjected to factor analysis which revealed five factors; personal motivation for safe behaviour, positive safety practice, risk justification, fatalism and optimism. This factor structure showed acceptable psychometric properties. Second, in an effort to produce a unidimensional scale with a small, but representative set of items, additional items were removed which had high correlation with other items. This resulted in loss of around half of the remaining items. The short scale contained 17 items with again overall acceptable psychometric properties. The most striking finding in the development of this questionnaire was that there was little variation between respondents on a very large proportion of the questions originally selected. Clearly there are well-known beliefs about safety in the working community which need to be understood in order to progress the concept of safety culture.  相似文献   
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INTRODUCTION: Many injury prevention interventions require changes in human behavior to reduce self-risk or risk to others. Promising injury prevention interventions may be discarded if they lack power to create a significant difference in outcomes when judging their ability to "move a person from nonaction or negative action to positive action (safety)." The transtheoretical model of change (TMC) allows greater sensitivity in detecting along the change process where an intervention may be effective. The stages of change consist of precontemplation, contemplation, preparation, action, maintenance, and termination. Change is not viewed as an "all or none phenomenon." METHOD: Use of the TMC was examined using a quasiexperimental, cross-over design involving high school agriculture students enrolled in 21 schools in Kentucky (n=9), Iowa (n=7), and Mississippi (n=5). A series of physical and narrative simulations (safety training exercises) were developed with a focus on preventing amputation, spinal cord injury, hypersensitivity pneumonitis, and noise-induced hearing loss. Contemplation and action, as part of the TMC, were measured using a 10-item, Likert-type, stages of change (SOC) instrument comprised of two subscales (reliability coefficients were.88 and.81, respectively). The final sample consisted of 790 students (373 treatment and 417 control). RESULTS: There was a significant group effect for both contemplation, F(1,732)=197.4; p<.0001, and action, F(1,730)=106.1; p<.0001. A convenience sample of 29 of the participating students was selected for follow-up farm visits 1 year postparticipation. Of these students, 25 (86%) had made safety behavior changes in their farm work. IMPACT ON INDUSTRY: The use of the TMC model can provide researchers with greater precision in examining intervention effectiveness in promoting change.  相似文献   
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