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881.
通过分析六种经典快速生物降解性测试方法的试验原理、操作特点以及限制因素,指出最好根据受试物对活性污泥呼吸抑制的EC50和EC20值,选择试验方法、受试物浓度和接种物浓度。比对了各方法在受试物适用浓度范围、接种物来源和前处理、无机培养基的配制和预处理、质量控制等方面的要求,指出快速生物降解性测试严禁接种物在接种前接触受试物;接种微生物的来源可能对试验结果影响很大;各方法需要的接种物浓度不同,建议采用平板计数方法确定并调整细菌数;对接种物和培养基进行有效的预处理,可减少空白值。应注意防止滤膜过滤和离心过程产生的有机碳干扰DOC的分析。列举了测试过程中常见的问题,强调应根据降解曲线分析试验结果;尽快研发跨区域、多来源的标准接种物。 相似文献
882.
室内环境质量现状及控制与预防措施 总被引:2,自引:0,他引:2
本文针对目前室内环境质量的现状,介绍了造成室内环境污染的污染物类型和对人体的危害及控制与预防措施,以引起大众对室内环境质量的关注。 相似文献
883.
Laura R. Perry Tom P. Moorhouse Andrew J. Loveridge David W. Macdonald 《Conservation biology》2020,34(4):879-890
Conflict between people and carnivores can lead to the widespread killing of predators in retaliation for livestock loss and is a major threat to predator populations. In Kenya, a large, rural, pastoralist population comes into regular conflict with predators, which persist across southern Kenya. We explored the social and psychological backdrop to livestock management practices in this area in a process designed to be easy to use and suitable for use across large areas for the study of conflict and transboundary implementation of wildlife conflict reduction measures, focusing on community involvement and needs. We carried out fully structured interviews of livestock managers with a survey tool that examined how social and psychological factors may influence livestock management behavior. We compared survey responses on 3 sites across the study area, resulting in 723 usable responses. Efficacy of individuals’ livestock management varied between and within communities. This variation was partially explained by normative and control beliefs regarding livestock management. Individual livestock managers’ self-reported management issues were often an accurate reflection of their practical management difficulties. Psychological norms, control beliefs, and attitudes differed among sites, and these differences partially explained patterns associated with conflict (i.e., variation in livestock management behavior). Thus, we conclude that a one-size-fits-all approach to improving livestock management and reducing human–predator conflict is not suitable. 相似文献
884.
885.
A comparison of web-based and telephone surveys for assessing traffic safety concerns, beliefs, and behaviors 总被引:1,自引:0,他引:1
Kenneth H. Beck Author Vitae Alice F. Yan Min Qi Wang 《Journal of Safety Research》2009,40(5):377-381
Introduction
The purpose of this investigation was to compare the results of a web-based and a telephone interview survey measuring driver concerns about a variety of traffic safety issues, their beliefs, and specific driving behaviors.Method
State-wide, annual random digit-dial telephone surveys and web-based surveys were conducted in Maryland. A total of 1,700 drivers were surveyed by telephone and 6,806 took a web survey.Results
Telephone respondents were more likely to be female and older. Web respondents were more likely to be white and not Latino/Hispanic. After controlling for demographic differences, telephone survey respondents were more likely to be concerned about traffic safety. They were more likely to believe that sobriety checkpoints reduce drunk driving (OR = 2.18, 95% CI 1.94, 2.45), they would be ticketed for not wearing a seat belt (OR = 1.26, 95% CI 1.12, 1.43), and they would be stopped by the police if they drove after drinking too much (OR = 1.17, 95% CI 1.03, 1.32). They were less likely to report a variety of risky behaviors including using a cell phone while driving (OR = .54, 95% CI .48, .61) and driving 10+ mph over the speed limit (OR = .81, 95% CI .72, .91), but were more likely to report having been ticketed for a moving violation in the last month (OR = 2.22, 95% CI 1.70, 2.90). Suggestions are offered for overcoming potential sources of sampling bias.Impact on Industry
Web-based surveys produce substantially different results than random-digit-dial telephone surveys, when used for public assessments of traffic safety concerns and behaviors. 相似文献886.
Mary Anne McDonald Author Vitae Hester J. Lipscomb Author Vitae Author Vitae Judith Glazner Author Vitae 《Journal of Safety Research》2009,40(1):53-61
Problem
Construction risk management is challenging.Method
We combined data on injuries, costs, and hours worked, obtained through a Rolling Owner-Controlled Insurance Program (ROCIP), with data from focus groups, interviews, and field observations, to prospectively study injuries and hazard control on a large university construction project.Results
Lost-time injury rates (1.0/200,000 hours worked) were considerably lower than reported for the industry, and there were no serious falls from height. Safety was considered in the awarding of contracts and project timeline development; hazard management was iterative. A top-down management commitment to safety was clearly communicated to, and embraced by, workers throughout the site.Discussion and Impact
A better understanding of how contracting relationships, workers' compensation, and liability insurance arrangements influence safety could shift risk management efforts from worker behaviors to a broader focus on how these programs and relationships affect incentives and disincentives for workplace safety and health. 相似文献887.
DIRK S. SCHMELLER††§§ BERND GRUBER‡‡ EDUARDAS BUDRYS† ERIK FRAMSTED‡ SZABOLCS LENGYEL§ KLAUS HENLE 《Conservation biology》2008,22(3):593-601
Abstract: One particular challenge in reducing the loss of biodiversity by 2010, as agreed on at the Earth Summit in 2002, is to assign conservation tasks to geographic or administrative entities (e.g., countries or regions) on different geographical scales. To identify conservation tasks, it is imperative to determine the importance of a specific area for the global survival of a species. So far, these national or subnational responsibilities for the conservation of species have been included differently in methods prioritizing conservation. We reviewed how 12 European and 3 non‐European methods determined national conservation responsibilities and evaluated the international importance of a biological population. Different countries used different methodologies, which made a direct comparison of assessments of national responsibilities among countries extremely difficult. Differences existed in the importance criteria used. Criteria included population decline, range reduction, rarity status, degree of isolation of a population, endemism, proportional distribution, and geographic location. To increase comparability, it is imperative to develop criteria for which data are generally available and to standardize the methodology among countries. A standardized method would allow conservation decisions to be based on the conservation status of a species and on the responsibility of a geographic or administrative entity for the survival of a species. We suggest that such a method should use a scalable index of proportional distribution, taxonomic status, and the distribution pattern of a taxon or species as key elements. Such a method would allow for the creation of hierarchical lists and would be highly relevant for parts of the world with multiple political jurisdictions or state unions and for nations with regional governmental structures. Conservation priorities could then be reasonably set by combining national responsibility assessments with the international conservation status of a species. 相似文献
888.
Environmental monitoring of aquatic systems is needed to estimate the quality of the systems, to evaluate standards and to
study stressor–response relationships. Monitoring programs often focus on the collection of biological, chemical and physical
measures of the system. An important concern is the effect of chemical and physical stressors on the biological community.
Evaluation of relationships may be difficult as the extent of the relationship is not known. From a management perspective,
interest is on what factors affect the biological community and where these factors have an influence. The focus of this paper
is on the use of regression based cluster analysis as a tool for finding relationships between a single biological response
and a suite of environmental stressors. The approach to cluster analysis uses a penalized regression classification likelihood
and Markov Chain Model Composition Monte Carlo. This approach allows for simultaneous development of regression models and
clustering of the regression models. The method is applied to the analysis of a data set describing stressors/response relationship
in Ohio. 相似文献
889.
890.
本文介绍了日本产业废弃物的采样方法并详细介绍了溶出试验和含量试验试液的制备方法及其适用范围,对测定重金属用试液的前处理方法也做了简要介绍。 相似文献