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841.
基于中国燃煤工业锅炉大气污染物排放及治理现状,并结合国家相关产业政策和国内外技术发展趋势,以2008年为基准年,分析测算了2015、2020年燃煤工业锅炉大气污染物排放量,提出了适合中国国情的燃煤工业锅炉大气污染物控制技术路线.依据研究的控制方案,2015年,烟尘、二氧化硫及氮氧化物排放量分别为507万、458万、230万t;2020年,烟尘、二氧化硫及氮氧化物排放量分别为491万、423万、269万t.与2008年相比,大气污染物排放量变化不大,基本上做到了增容不增污.在此基础上,提出了燃煤工业锅炉大气污染物防治建议.  相似文献   
842.
为更加精准地判定采空区自燃危险区域,对煤自燃极限参数的计算方法进行改进,采用能量守恒微分方程的分析解计算煤自燃所需必要条件的极限值;以内蒙古凯达煤矿为例对该方法进行验证,根据浮煤的物性参数以及采空区环境条件,计算分析46205工作面回风侧采空区煤的自燃危险性;根据采空区漏风条件以及煤自燃所需要的氧浓度值,分析在遗煤较厚...  相似文献   
843.
生态监测指标选择一般过程探讨   总被引:10,自引:2,他引:8  
本文对生态监测指标体系设计的一般过程进行了详细的分析和论述。主要包括生态监测目标、生态系统所受的环境压力、生态系统模型的提出以及生态监测指标的分类。旨在为我国生态监测规划和设计进行初步的探索。  相似文献   
844.
通过分析成都平原城市群8个城市2015-2019年春季(4-5月)地面臭氧浓度及超标情况表明,春季成都平原平均臭氧日最大8小时平均浓度(O3_8 h)呈上升趋势,成都、眉山O3超标日较多,雅安最少但呈逐年增加趋势,资阳、乐山O3_8 h平均值和O3超标率高于夏季.同时,利用ERA-Interim再分析资料和PCT客观天...  相似文献   
845.
The purpose of this study is merely to review the current situation in the designing and implementation of the emission trading programs in Europe. Historical data show that although there is a series of shortcomings in their current functioning, employing such instruments for GHG reduction policy making is strongly expected to be efficient and effective. The European Union Emission Trading Scheme (EU ETS), Clean Development Mechanism (CDM) and Joint Implementation (JI) are just a few examples of the ambitious EU initiative that heavily relies on such instruments. We dwell on their operations and achievements by far and all the content in this article is expected to convince the Chinese government and regional public authorities to take positive actions and attitudes in promoting these instruments.  相似文献   
846.
The Mekong River Basin is considered to be the second most species rich river basin in the world. The 795,000 km(2) catchment encompasses several ecoregions, incorporating biodiverse and productive wetland systems. Eighty percent of the rapidly expanding population of the Lower Mekong Basin (LMB), made up in part by Lao PDR, Thailand, Cambodia and Viet Nam, live in rural areas and are heavily reliant on wetland resources. As the populations of Cambodia and Lao PDR will double in the next 20 years, pressure on natural resources and particularly wetlands can only increase. For development planning, resource and conservation management to incorporate wetland issues, information on the distribution and character of Mekong wetlands is essential. The existing but outdated wetland maps were compiled from secondary landuse-landcover data, have limited coverage, poor thematic accuracy and no meta-data. Therefore the Mekong River Commission (MRC) undertook to produce new wetland coverage for the LMB. As resources, funding and regional capacity are limited, it was determined that the method applied should use existing facilities, be easily adaptable, and replicable locally. For the product to be useful it must be accepted by local governments and decision makers. The results must be of acceptable accuracy (>75%) and the methodology should be relatively understandable to non-experts. In the first stage of this exercise, field survey was conducted at five pilot sites covering a range of typical wetland habitats (MRC wetland classification) to supply data for a supervised classification of Landsat ETM images from the existing MRC archive. Images were analysed using ERDAS IMAGINE and applying Maximum Likelihood Classification. Field data were reserved to apply formal accuracy assessment to the final wetland habitat maps, with resulting accuracy ranging from 77 to 94%. The maps produced are now in use at a Provincial and National level in three countries for resource and conservation planning and management applications, including designation of a Ramsar wetland site of international importance.  相似文献   
847.
企业职业危害综合评价和风险分级系统及其应用   总被引:4,自引:2,他引:2  
我国企业职业危害形势依然十分严峻,2007年共诊断各类职业病14296例,较2006年增加了24.11%。由于国家在一段时期内不太可能大幅度增加监管人员数量,因此,实施企业职业危害分级监管成为职业危害监管工作的一个紧迫需求。本文从提高企业监管信息化水平角度出发,开发企业职业危害综合评价和风险分级系统。系统即可为政府实施职业危害分级监管提供强有力的技术支撑,也可应用在企业的作业场所职业危害管理工作中,从而提高政府和企业职业危害管理工作技术水平和效率。  相似文献   
848.
以香港青山B电厂4×680MW机组排放控制工程(CPBEC)为例,介绍了海外环保EPC项目OHS风险控制的特点和风险控制方案,阐述了目前国内环保企业OHS风险管理中存在的主要问题和改进措施。  相似文献   
849.
Abstract: Consistency in determining Rosgen stream types was evaluated in 12 streams within the John Day Basin, northeastern Oregon. The Rosgen classification system is commonly used in the western United States and is based on the measurement of five stream attributes: entrenchment ratio, width‐to‐depth ratio, sinuosity, slope, and substrate size. Streams were classified from measurements made by three monitoring groups, with each group fielding multiple crews that conducted two to three independent surveys of each stream. In only four streams (33%) did measurements from all crews in all monitoring groups yield the same stream type. Most differences found among field crews and monitoring groups could be attributed to differences in estimates of the entrenchment ratio. Differences in entrenchment ratio were likely due to small discrepancies in determination of maximum bankfull depth, leading to potentially large differences in determination of Rosgen’s flood‐prone width and consequent values of entrenchment. The result was considerable measurement variability among crews within a monitoring group, and because entrenchment ratio is the first discriminator in the Rosgen classification, differences in the assessment of this value often resulted in different determination of primary stream types. In contrast, we found that consistently evaluated attributes, such as channel slope, rarely resulted in any differences in classification. We also found that the Rosgen method can yield nonunique solutions (multiple channel types), with no clear guidance for resolving these situations, and we found that some assigned stream types did not match the appearance of the evaluated stream. Based on these observations we caution the use of Rosgen stream classes for communicating conditions of a single stream or as strata when analyzing many streams due to the reliance of the Rosgen approach on bankfull estimates which are inherently uncertain.  相似文献   
850.
Hydrologic landscapes (HLs) have proven to be a useful tool for broad scale assessment and classification of landscapes across the United States as they help organize larger geographical areas into areas of similar hydrologic characteristics. We developed a HL classification for the Bristol Bay watershed of southwest Alaska that incorporates indices of annual climate and seasonality, terrain, geology, and the influences of large lakes and glaciers. A HL classification is particularly useful in this large watershed because of its hydrologic and landscape variability, important salmon fishery, variety of environmental and potential anthropogenic stressors, and lack of widespread hydrologic data. Following creation of Bristol Bay basin‐wide HL classes, we compared the HL distributions within watersheds grouped by two calculated runoff parameters derived from available long‐term streamflow records and found HL distributions within these groups provided predictive insight on hydrologic behavior. Using these developed runoff groups, we estimated expected hydrologic behavior in watersheds across the larger Bristol Bay watershed that lacked gauged streamflow records. The HL approach provides a scientific basis for estimating the first‐order hydrologic behavior of watersheds and landscapes that lack detailed hydrologic information.  相似文献   
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