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141.
Forests play a fundamental role in the global carbon cycle and can be managed to mitigate greenhouse gas emissions and conserve or sequester carbon. Global policy and environmental changes can affect regional consumption of forest products, as well as inter-regional trade of forest goods and services. This study analyzes global and regional change impacts on the production, consumption and trade of forest products in two Nordic countries, Finland and Sweden. Annual data on removal and trade (1964–2012) for roundwood and sawnwood is used to identify structural breaks based on Chow tests. According to the analysis, the time period is divided into two periods: t1 (1964–1980) and t2 (1981–2012). In the first period, breaks occurred in 1975 and 1976 in the Finnish model and no break is found in the Swedish model. In the second period, we identify breaks in 1991 and 1992 for the Finnish model and in 2004, 2005 and 2006 for the Swedish model. Although our findings have broad empirical support, we do not identify any specific incident as a direct cause of the changes in the consumption and trade patterns of the two types of wood in these countries. The models and analysis presented here can serve as methodological tools for policymakers to better understand the effects of structural changes in the production of forest goods and services in the Nordic region and globally.  相似文献   
142.
After extensive flooding in 2002, the European Union Solidarity Fund (EUSF) was created as an ex post loss-financing vehicle for EU member states and candidate countries in the case of disasters that exceed the government’s resources to cope. The EUSF is viewed as a valuable instrument for pooling risk among countries in Europe and potentially as a model for financing loss and damage from climate change in vulnerable countries worldwide. This paper assesses its future prospects taking account of reforms adopted in 2014. Our analysis is based on three recognized aims of the Solidarity Fund: its promotion of solidarity with those countries having the least capacity to cope with major disasters; its contribution to proactive disaster risk reduction and management (climate adaptation); and its robustness with regard to its risk of depletion (stress testing). Using a simulation approach for future disasters, we conclude that the reformed EUSF’s risk of depletion, although it is reasonably robust to more frequent disasters, could be reduced by increasing member state contributions and/or engaging in risk transfer. The European Commission has taken important steps in linking the fund to proactive risk reduction; yet, by changing its budgeting practices, the commission could be more proactive in encouraging risk management in member states. In its current form, the EUSF does not embed needs-based solidarity. Lower-income “new” member states have received disproportionately less compensation in terms of eligible losses, although on average, they have received more disaster aid than what they contribute to the fund. Solidarity could be enhanced by changing the rules for disbursing aid. After briefly describing alternative risk-pooling models in the Caribbean, Africa, and Europe, we suggest how design features of the EUSF as compared to other regional risk pools can inform discussions on the Warsaw International Loss and Damage Mechanism.  相似文献   
143.
We present a methodology for using a domestic water use time series that were obtained from Yellow River Conservancy Commission, together with the climatic records from the National Climate Center of China to evaluate the effects of climate variability on water use in the Yellow River Basin. A suit of seven Global Circulation Models (GCMs) were adopted to anticipate future climate patterns in the Yellow River. The historical records showed evidences of rises in temperature and subsequent rises in domestic water demand in the basin. For Upstream of Longyangxia region, the impact was the least, with only 0.0021?×?108 m3 for a temperature increase of 1 °C; while for Longyangxia-Lanzhou region, domestic water use was found to increase to 0.18?×?108 m3 when temperature increases 1 °C. Downstream of Huayuankou was the region with the most changes in temperature that gave the highest increase of 1.95?×?108 m3 in domestic water demand for 1 °C of change of temperature. Downstream of Huayuankou was identified as the most vulnerable area, where domestic water demand increases nearly by 42.2 % with 1 °C increase of temperature. Judging from the trends of temperature range, we concluded that future temperature in Yellow River Basin has an increasing tendency. This could worsen the existing issues of domestic water demand and even more to trigger high competition among different water-using sectors.  相似文献   
144.
Institutions are one of the decisive factors which enable, constrain and shape adaptation to the impacts of climate change, variability and extreme events. However, current understanding of institutions in adaptation situations is fragmented across the scientific community, evidence diverges, and cumulative learning beyond single studies is limited. This study adopts a diagnostic approach to elaborate a nuanced understanding of institutional barriers and opportunities in climate adaptation by means of a model-centred meta-analysis of 52 case studies of public climate adaptation in Europe. The first result is a novel taxonomy of institutional attributes in adaptation situations. It conceptually organises and decomposes the many details of institutions that empirical research has shown to shape climate adaptation. In the second step, the paper identifies archetypical patterns of institutional traps and trade-offs which hamper adaptation. Thirdly, corresponding opportunities are identified that enable actors to alleviate, prevent or overcome specific institutional traps or trade-offs. These results cast doubt on the validity of general institutional design principles for successful adaptation. In contrast to generic principles, the identified opportunities provide leverage to match institutions to specific governance problems that are encountered in specific contexts. Taken together, the results may contribute to more coherence and integration of adaptation research that we need if we are to foster learning about the role of institutions in adaptation situations in a cumulative fashion.  相似文献   
145.
This paper employs a review of the technical literature to estimate the potential decrease in greenhouse gas (GHG) emissions that could be achieved by increasing the application of gas engines in China in three sectors: urban public transport vehicle; shipping; and thermal power plants. China’s gas engine development strategies and three types of gas resource are discussed in the study, which indicates that gas engines could decrease GHG emissions by 520 megatonnes (Mt) of carbon dioxide equivalent (CO2e) by 2020. This would account for 9.7 % of the government’s target for decreasing GHG emissions and is dominated by methane recovery from the use of coal mine gas (CMG) and landfill gas (LFG) for power generation. In the public urban transport vehicle and shipping sectors the low price of natural gas and the increasing demand for the control of harmful emissions could spur the rapid uptake of gas engine vehicles. However, the development of CMG- and LFG-fuelled power plants has been limited by the unwillingness of local enterprises to invest in high-performance gas engine generators and the associated infrastructure. Therefore, further compulsory policies that promote CMG use and LFG recovery should be implemented. Moreover, strict regulations on limiting methane leakage during the production and distribution of gas fuels are urgently needed in China to prevent leakage causing GHG emissions and largely negating the climate benefits of fuel substitution. Strategies for increasing the application of gas engines, promoting gas resources and recovering methane in China are instrumental in global GHG mitigation strategies.  相似文献   
146.
As highlighted in the outcome of the Paris Agreement at the 21st Conference of Parties of the United Nations Framework Convention on Climate Change there has been a recent push for the stronger mitigation actions of cities, regions, and local governments. Energy efficiency is a tool that can be leveraged by not only industry or national governments but also cities, regions, and local governments for mitigation purposes. However, studies on energy efficiency as a mitigation tool thus far have focused on the national or transnational scale, and on certain sectors of industry. The purpose of this paper is to find the most cost-efficient energy efficiency measures (EEMs) at the city, region, and local government level. To that end, this paper examines the yearly energy savings and greenhouse gas (GHG) reduction intensity, as well as energy savings and GHG reduction efficiency, in the case of EEMs conducted by South Korean local governments. Yearly energy savings intensity and GHG reduction intensity are estimated to be in the range of 0.094~0.375 tonne of oil equivalent (TOE)/M-KRW (million Korean won) and 0.287~1.180 tCO2e/M-KRW. Results show that inverter installation at water and sewage treatment plants and improvement of pump efficiency are the most cost-efficient EEMs. Moreover, energy savings efficiency and GHG reduction efficiency are within the range of 18.29~45.31 %, at an average of 30.5 % GHG reduction potential. If this reduction potential is applied to the buildings and facilities regulated and run by cities/local governments, there is a worldwide reduction potential of 1.023 billion tCO2 compared to 2020 business as usual levels.  相似文献   
147.
近年来随着水环境模拟领域的发展出现了较多水环境数学模型,目前日益成熟的WebGIS技术是使模型使用变得简单化和直观化的一大途径.是在通过Flex和ArcGIS Server搭建WebGIS系统平台的基础上,利用PHP进行WebGIS和水环境模拟模型的数据交互,实现系统平台和数值模型的松散耦合.用户在浏览器端进行模型输入条件的设置,模型在远程服务器端进行运行计算,反馈的模拟结果通过RIA在WebGIS中进行多元化动态展示.该方法对一般模型具有适用性,可降低模型使用门槛,提高模拟结果展示和分析能力.  相似文献   
148.
以四川省蓬安县为例,基于GIS空间分析技术,结合蓬安当地实际,选取水源涵养、土壤保持能力和生物多样性进行生态敏感性评价,获得蓬安县区域敏感性现状图,并以此为基础构建生态安全格局,该格局注重区域的内在机理与周围的相对联系,保证各生态环境功能区成为具有各自特点、功能和生命活力而又彼此联系的有机体,为其生态文明建设过程中重点领域和重点工程设计规划提供基础支撑,阐明了生态敏感性评价在生态文明建设中的运用,为县级生态文明建设规划做出了贡献.  相似文献   
149.
为了研究地表参数取值对AERMOD中面源模拟预测浓度值的影响,文章通过改变粗糙度、反照率和波文比的取值来进行不同地表参数与预测结果的相关性分析,同时采用正交试验法来研究不同地表参数对预测结果的敏感性.相关性分析表明,不同地表参数和预测结果有着很高的相关性.敏感性分析表明,反照率数值变化对小时最大落地浓度的敏感性最大,粗糙度数值变化对日均和年均最大落地浓度的敏感性最大.通过研究可以看出在面源大气预测过程中合理选择地表参数值是准确预测的前提.  相似文献   
150.
Heat and free chlorine are among the most efficient and commonly used treatments to inactivate enteric viruses, but their global inactivation mechanisms have not been elucidated yet. These treatments have been shown to affect at least the capsid proteins of viruses and thus may affect the surface properties (i.e. electrostatic charge and hydrophobicity) of such particles. Our aim was to study the effects of heat and free chlorine on surface properties for a murine norovirus chosen as surrogate for human norovirus. No changes in the surface properties were observed with our methods for murine norovirus exposed to free chlorine. Only the heat treatment led to major changes in the surface properties of the virus with the expression of hydrophobic domains at the surface of the particles after exposure to a temperature of 55 °C. No modification of the expression of hydrophobic domains occurred after exposure to 60 °C, and the low hydrophobic state exhibited by infectious and inactivated particles after exposure to 60 °C appeared to be irreversible for inactivated particles only, which may provide a means to discriminate infectious from inactivated murine noroviruses. When exposed to a temperature of 72 °C or to free chlorine at a concentration of 50 mg/L, the genome became available for RNases.  相似文献   
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