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131.
自然环境对风力发电机组安全运行的影响分析   总被引:1,自引:0,他引:1  
风力发电机组野外运行的特点决定了自然环境条件对其运行状况有着重要的影响,本文综述了气压、气温、台风、雷击、盐雾等自然条件对风力发电机组的影响状况,并对其产生的机理进行了分析,给出在各种自然环境下的风电机组设计和运行应对措施,以提高风电机组对自然环境条件的适应性。希望本文能对国内风电机组的设计制造、运行维护提供一定的参考和帮助。  相似文献   
132.
根据常规事故树定量计算中基本事件概率的不确定性问题,通过引入模糊集的概念,将常规事故树中基本事件的发生概率模糊化,用三角形模糊数代替确定性发生概率,应用模糊数截集方法,推导了模糊事故树的相关算法.采用模糊事故树方法得到饮食业油烟道火灾事故发生概率,并进行了敏感性分析,找出对顶事件发生概率影响较大的基本事件,确认减小油烟道火灾事故发生的相关措施.研究表明,饮食业油烟道火灾事故概率的模糊事故树分析是切实可行的,有助于对饮食业油烟道火灾的认识、预防和扑救工作.  相似文献   
133.
The monitoring of pharmaceuticals and personal care products (PPCPs) has focused on the distribution in rivers and small lakes, but data regarding their occurrence and effects in large lake systems, such as the Great Lakes, are sparse. Wastewater treatment processes have not been optimized to remove influent PPCPs and are a major source of PPCPs in the environment. Furthermore, PPCPs are not currently regulated in wastewater effluent. In this experiment we evaluated the concentration, and corresponding risk, of PPCPs from a wastewater effluent source at varying distances in Lake Michigan. Fifty-four PPCPs and hormones were assessed on six different dates over a two-year period from surface water and sediment samples up to 3.2 km from a wastewater treatment plant and at two sites within a harbor. Thirty-two PPCPs were detected in Lake Michigan and 30 were detected in the sediment, with numerous PPCPs being detected up to 3.2 km away from the shoreline. The most frequently detected PPCPs in Lake Michigan were metformin, caffeine, sulfamethoxazole, and triclosan. To determine the ecological risk, the maximum measured environmental concentrations were compared to the predicted no-effect concentration and 14 PPCPs were found to be of medium or high ecological risk. The environmental risk of PPCPs in large lake systems, such as the Great Lakes, has been questioned due to high dilution; however, the concentrations found in this study, and their corresponding risk quotient, indicate a significant threat by PPCPs to the health of the Great Lakes, particularly near shore organisms.  相似文献   
134.
针对煤矿生产物流系统安全影响因素众多、各因素对煤矿安全影响作用复杂的问题,提出基于粗糙集和IPA定位分析法的煤矿生产物流系统安全影响因素分析模型。首先运用粗糙集属性重要度思想对煤矿安全影响因素进行排序,然后采用IPA定位分析法识别不同安全状态煤矿安全生产的制约因素,最后通过对河南义马煤业集团跃进煤矿进行实证分析验证模型的可行性。结果表明,各因素对煤矿安全影响的重要度由大到小排序为通风设施、通风安全监控、通风技术管理、排水设备配置、机电安全管理、排水技术人员配备(采掘关系)、采掘机械、排水机构设置、安全运输、应急救援、采掘技术管理,且对于不同安全状态等级的煤矿而言,制约其安全的主要因素也不相同。  相似文献   
135.
针对高硫煤机组FGD的技术特点,从设计源头介绍了如何提升高硫煤机组FGD可靠性的措施,并佐以工程实例。  相似文献   
136.
Objectives: In this study, we aimed to determine whether three minimum legal drinking age 21 (MLDA-21) laws—dram shop liability, responsible beverage service (RBS) training, and state control of alcohol sales—have had an impact on underage drinking and driving fatal crashes using annual state-level data, and compared states with strong laws to those with weak laws to examine their effect on beer consumption and fatal crash ratios.

Methods: Using the Fatality Analysis Reporting System, we calculated the ratio of drinking to nondrinking drivers under age 21 involved in fatal crashes as our key outcome measure. We used structural equation modeling to evaluate the three MLDA-21 laws. We controlled for covariates known to impact fatal crashes including: 17 additional MLDA-21 laws; administrative license revocation; blood alcohol concentration limits of.08 and.10 for driving; seat belt laws; sobriety checkpoint frequency; unemployment rates; and vehicle miles traveled. Outcome variables, in addition to the fatal crash ratios of drinking to nondrinking drivers under age 21 included state per capita beer consumption.

Results: Dram shop liability laws were associated with a 2.4% total effect decrease (direct effects: β =.019, p =.018). Similarly, RBS training laws were associated with a 3.6% total effect decrease (direct effect: β =.048, p =.001) in the ratio of drinking to nondrinking drivers under age 21 involved in fatal crashes. There was a significant relationship between dram shop liability law strength and per capita beer consumption, F (4, 1528) = 24.32, p <.001, partial η2 =.016, showing states with strong dram shop liability laws (Mean (M) = 1.276) averaging significantly lower per capita beer consumption than states with weak laws (M = 1.340).

Conclusions: Dram shop liability laws and RBS laws were both associated with significantly reduced per capita beer consumption and fatal crash ratios. In practical terms, this means that dram shop liability laws are currently associated with saving an estimated 64 lives in the 45 jurisdictions that currently have the law. If the remaining 6 states adopted the dram shop law, an additional 9 lives could potentially be saved annually. Similarly, RBS training laws are associated with saving an estimated 83 lives in the 37 jurisdictions that currently have the laws. If the remaining 14 states adopted these RBS training laws, we estimate that an additional 28 lives could potentially be saved.  相似文献   
137.
可燃气体(液体蒸气)爆炸测试装置的改进研究   总被引:3,自引:2,他引:1  
以可燃气体(液体蒸气)爆炸测试装置改进为主线,综述国内外各种测试装置的优缺点。对不同装置、测试方法以及测试原理进行比较分析,研讨可燃气体爆炸的特点和爆炸参数测试方法以及对现有测试装置的改进方案。即对20 L爆炸测试装置的配气系统和控制系统进行了合理改进,使引射混合配气与循环混合配气相结合,使可燃气体(液体蒸气)与空气混合更均匀,控制操作更简便,还指出了今后研究工作中应注意的一些问题和研究重点。  相似文献   
138.
集对分析法在河流水质评价中的应用   总被引:5,自引:0,他引:5  
为了解决集对分析法在环境质量评价中应用的问题,用集对分析法建立了河流水质评价模型,并应用该模型对阜新市大凌河支流4个断面监测点的7种污染因子监测结果进行实例分析.结果表明,各断面水质评价级别均为Ⅴ级.研究表明,采用集对分析法进行水质评价准确可靠,信息利用率高,具有客观性和合理性.因此,集对分析理论为河流水质综合评价提供了一种新的思路,所用理论方法和所建模型也可推广应用于其他领域.  相似文献   
139.
三江源地区1961~2005年气温极端事件变化   总被引:3,自引:0,他引:3  
利用三江源地区11个气象台站1961~2005年逐日最高气温和最低气温资料,分析了三江源地区极端高温和极端低温的变化趋势。研究表明:近45年来,白天和夜间温度极端偏高的日数明显增多,分别以26 d/10 a和44 d/10 a速度在增加;白天和夜间温度极端偏低的日数显著减缓,分别以41 d/10 a和85 d/10 a的速度显著减少;年极端低温和极端高温分别以042℃/10 a和029℃/10 a的速度增加;白天和夜间温度极端偏高的日数增加主要发生在冬季和夏季,而白天和夜间温度极端偏低的日数减少主要发生在春季和秋季,夜间温度极端偏低的日数减少趋势最为明显;长江源地区极端气温变化对区域增温的响应更为敏感。  相似文献   
140.
ABSTRACT: A visual selection technique can be utilized to locate potential well field sites prior to on-site testing. The technique is based upon an understanding of the regional hydrology and an appreciation for development goals such as the identification of high-yield and low-impact locations. Although the uniqueness of Pasco, Pinellas, and Hillsborough Counties in Western Florida has been incorporated into the current application, the methodology, with modifications, is transferable to other geographic regions. Overlays of each criterion used in site selection are combined to form a regional composite showing favorable site locations and further serve a useful communications role as visual aids during public presentation. Implications of direct and indirect cost savings to the public are obtained when the methodology is applied to the location of municipal well fields.  相似文献   
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