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101.
Cities globally face significant risks from climate change, and are taking an increasingly active role in formulating and implementing climate change adaptation policy. However, there are few, if any, global assessments of adaptation taking place across cities. This study develops and applies a framework to track urban climate change adaptation policy using municipal adaptation reporting. From 401 local governments globally in urban areas with >1 m people, we find that only 61 cities (15%) report any adaptation initiatives, and 73 cities (18%) report on planning towards adaptation policy. We classified cities based on their adaptation reporting as extensive adaptors, moderate adaptors, early stage adaptors, and non-reporting. With few exceptions, extensive adaptors are large cities located in high-income countries in North America, Europe, and Oceania, and are adapting to a variety of expected impacts. Moderate adaptors usually address general disaster risk reduction rather than specific impacts, and are located in a mix of developed and developing countries. Early stage adaptors exhibit evidence of planning for adaptation, but do not report any initiatives. Our findings suggest that urban adaptation is in the early stages, but there are still substantive examples of governments taking leadership regardless of wealth levels and institutional barriers.  相似文献   
102.
With the endless strengthening of the economic globalization trend, the world market gradually steps into a new turn of the market integration period. Market integration in China is always the key study field of academic communities, but it is developed late, whatever content system or methodology shall be greatly improved as expected. This paper aims at summarizing and reviewing the study on the content system and main demonstrations of market integration in order to provide theoretical guide and methodological basis for related studies.  相似文献   
103.
There has been much debate about the assessment process of the Intergovernmental Panel on Climate Change (IPCC). Yet two of the most fundamental challenges that directly threaten the ability of the IPCC to fulfill its mandate have been largely neglected so far. Firstly, the magnitude and rapid expansion of the climate change literature makes it increasingly impossible for the IPCC to conduct comprehensive and transparent assessments without major innovations in assessment practices and tools. Secondly, the structure, organization and scientific practices across the social sciences and humanities prohibit systematic learning on climate change solutions and increasingly limit the policy-relevance of IPCC assessments. We highlight the need for responses along three avenues to prepare the IPCC for continued success in the future: 1) IPCC assessments must make better use of big-data methods and available computational power to assess the growing body of literature and ensure comprehensiveness; 2) systematic review practices need to be enshrined into IPCC procedures to ensure adequate focus and transparency in its assessments; 3) a synthetic research culture needs to be established in the social sciences and humanities in order to foster knowledge accumulation and learning on climate solutions in the future. As policymakers become more interested in understanding solutions, the future prospects of global environmental assessment enterprises will depend heavily on a successful transformation within the social sciences and humanities towards systematic knowledge generation. This article is part of a special issue on solution-oriented Global Environmental Assessments.  相似文献   
104.
2003年是全球自然灾害重灾年.根据收集到的全球自然灾害记录的数据,客观地对全球主要自然灾害的特征和分布特点进行了分析,并对其成因和发展趋势进行了初步探讨.  相似文献   
105.
本文讨论了宇宙环境中的化学概况,特别是宇航环境化学和宇航适应问题。  相似文献   
106.
The present study sought to objectively demonstrate how a researcher can, in a structured way, select relevant articles about alternative heterogeneous catalysts in photocatalytic processes. Therefore, the ProKnow-C (Knowledge Development Process – Constructivist) method was used to systematize the results found, with the application bibliometric and systematic analysis techniques for the evaluation of the results. The search string adopted as criteria was: solar photocatalysis AND heterogeneous catalysts OR alternative catalysts AND effluents. The databases were Web of Science, Science Direct and Scopus. The final bibliographic portfolio obtained for the research theme was made up of 19 articles. It was possible to verify advances in the number of publications on the theme over the evaluated period, with the Journal of Photochemistry and Photobiology A: Chemistry standing out in the final portfolio. Evaluating each article in the portfolio individually, it was possible to verify that most studies use combinations of catalysts already reported to create an alternative material to those already investigated in the literature. Those that use waste as catalysts chose to source this material from treatment plants and the steel industry. Around 58% of the papers used hydrogen peroxide in their processes, while 42% chose not to use it. Finally, approximately 63% of the papers in the portfolio used synthetic effluent in their processes, while the rest (37% of the research) chose to use real effluent. The results obtained in this research by applying the method can contribute to studies related to heterogeneous photocatalysis by alternative means over the years.  相似文献   
107.
职业危害因素混合接触综合评价方法概述   总被引:1,自引:0,他引:1  
作业场所同时接触多种职业危害因素的综合危害性日益引起广泛关注,如何对其进行科学的评价成为职业危害研究者面临的重要课题。本文对不同危害因素的混合危害作用的评价方法进行了系统的总结与归纳,探讨了混合作用的描述方法,分析了毒理学、流行病学、风险评价三大类方法应用于混合危害作用评价时的基本原理、核心思路和实施流程,此外对三种方法的特点进行了对比分析。  相似文献   
108.
This paper describes one example of how the UK National Air Quality Strategy (NAQS) is implemented in a local urban environment. The paper reviews the beginning of this process, by examining the review and assessment procedures of the NAQS in the London Borough of Barnet. By the application of available UK tools of local air quality management (LAQM), the process began through analysis of the levels of local emissions and progressed onto modelling of current and future air quality. A map showing combined emission hotspot areas for the Borough indicated and higher emission rates occur in the south of the Borough and along the major transport corridors, as road sources dominate emissions. Dispersion modelling studies were also conducted for this purpose, using the screening models GRAM, PGRAM and ADMS Urban for an in-depth assessment. These analyses found that some local point sources and the majority of Borough roads with over 20,000 vehicles per day produced exceedances of the future objectives for air quality for some pollutants.Recommendations for the progression of LAQM in the Borough are made and include the update and expansion of the emissions information held for use in future modelling studies. The paper demonstrates the experience of implementing the Strategy, using the tools and procedures available for this purpose, in a local urban environment that is similar to many in the UK.  相似文献   
109.
钻井环境污染过程控制技术综述   总被引:3,自引:1,他引:2  
钻井环境污染控制是实现清洁钻井的必要手段,文章介绍了钻井过程中的污染物和钻井作业环境污染控制措施,重点综述了钻井废水、废气、固体废物和噪声等环境污染控制技术。通过钻井环境污染过程控制将钻井作业对环境影响和危害的程度降至最低。  相似文献   
110.
Environmental research varies in its methodological quality, degree of bias, and relevance to policy questions. Using this heterogeneous, and sometimes polarised, research to inform environmental policies can be challenging. Policy-making in the healthcare field sometimes uses systematic reviews (SRs) to tackle these issues and present a comprehensive, policy-neutral, transparent and reproducible synthesis of the evidence. However, there is less familiarity with SRs in the environmental field. The aim of this article is to: (1) summarise the process of conducting SRs, using best practice methods from the healthcare field as an example, (2) explain the rationale behind each stage of conducting a SR, and (3) examine the prospects and challenges of using SRs to inform environmental policy. We conclude that existing SR protocols from healthcare can be, and have been, applied successfully to environmental research but some adaptations could improve the process. The literature search stage could be expedited by standardising the reporting and indexing of environmental studies, equivalent to that in the healthcare field. The consistency of the study appraisal stage of SRs could be augmented by refining the existing quality assessment tools used in the healthcare field, enhancing their ability to discriminate quality and risk of bias in non-randomised studies. Ultimately, the strength of evidence within SRs on environmental topics could be improved through more widespread use of randomised controlled trials as a research method, owing to their inherently lower risk of bias when conducted according to best practice.  相似文献   
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