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361.
The CAL3QHC model was used to predict carbon monoxide (CO) concentrations from motor vehicles at an existing urban intersection (Star Cinema in Muscat area, Oman). The CO concentrations predicted from the model were compared with those measured in the field. Predicted average CO concentrations were found to compare favorably with measured values obtained at all eight receptors considered within the modeled intersection. In general, the comparison indicates good agreement with some underprediction for CO. For receptor 6, the model overpredicts the average CO concentration. This overprediction is associated with the presence of trees and green area in the location of receptor 6. In general, the measurements and the model results indicated that the highest CO concentrations were found to occur close to the intersection and, hence, a decrease in the concentration levels was seen as the distance from the road increased. The results indicated that the levels of CO were well below the ambient air quality standard and that probably no health risk was present in areas adjacent to the star cinema intersection. However, the predicted worst-case 1-h CO concentrations assuming inversion atmospheric stability conditions (class F) and wind speed of 1 m/s indicated that the levels of CO were close to or higher than the Omans National Ambient Air Quality Standards (NAAQS) value of 35 ppm at all receptors considered. The results of this study are useful in transport development and traffic management planning.Published online.  相似文献   
362.
中美两国汽车驾驶安全影响因素研究   总被引:8,自引:4,他引:4  
影响汽车驾驶安全的各国道路交通系统以及驾驶员的驾驶行为等存在着差异性 ,许多差异可以通过统计数据的分析 ,或者其他定量研究方法获取 ,但仍然有许多影响驾驶安全的因素难以发现。笔者通过焦点团体座谈会的方法 ,从驾驶者的角度 ,搜集并分析了中美两国驾驶安全的主要影响因素 ,以及具有美国驾驶经历会对我国驾驶员有何影响。通过中美两国定性数据的对比分析 ,得出了主要影响因素 ,与此同时 ,通过问卷调查定量地分析了这些因素的严重程度。  相似文献   
363.
The impoundment of the Kootenai River by Libby Dam caused changes in discharge and water quality in the river downstream from Lake Koocanusa. The changes observed downsteam were largely attributable to the depth of withdrawal from the reservoir and the reservoir's ability to store and mix various influent water masses. The preimpoundment and postimpoundment time series of discharge and six water quality variables were autocorrelated and exhibited strong seasonality. Intervention analysis, a technique employing Box-Jenkins time series models, was used to quantify the nature and magnitude of the changes in water quality after the construction of Libby Dam. The models were developed with data from June 1967 through February 1981 and were able to satisfactorily forecast riverine conditions from March 1981 through January 1982.  相似文献   
364.
The purpose of this study was to assess the effects of a two-day post-license driver-training program on brake performance in cars with antilock braking systems (ABS). A trainee group (n = 26) and a control group (n = 13) participated in the experiment. The trainee group were enrolled in a two-day training course that included instruction in a braking technique that may be used in cars with and without ABS. All participants performed emergency brake tests from 80 and 100 km h−1 in an instrumented car before and after the training period. Results indicated the post-training group used a smoother braking profile, were less reliant on ABS activation, had enhanced postural stability, but took about one car length longer to stop from 100 km h−1 compared with the control group. Implications of these results for braking in cars with and without ABS, and for driver education programs in general are discussed.  相似文献   
365.
An experimental study of road building and recycling of used pavement has been conducted within the framework of a Life Cycle Analysis. Four equivalent asphalt concretes made with different recycling rates have been investigated during road construction. Airborne emissions, pollutant release over time and odor production related to asphalt laying have all been determined and compared among the various recycling rates. All of the results (VOC, PAH and odors), expressed in terms of concentrations and fluxes, exhibit quite monotonic variations with respect to the recycling rate. These results, however, did not reveal the same trend as a function of the recycling rate (increases or decreases), depending on the selected target parameter (VOC or PAH). Indicators have been proposed for a discussion of results that take into account: (i) raw material emissions with respect to the reference defined in the case of pavement without reclaimed asphalt; and (ii) emissions in each case from all material production sources.  相似文献   
366.
乌鲁木齐城市道路地面径流中重金属的污染特征分析   总被引:1,自引:0,他引:1  
采用原子吸收光谱法,对乌鲁木齐市城区3个采样点的两次降雨过程中采集的路面径流进行了重金属Zn、Pb、Cd、Cu和Ni的含量分析.结果表明,道路径流中Zn、Pb、Cd污染较严重,但随着时间的推移,它们在雨水径流中的含量逐渐减少,符合"浓度初期冲刷"规律.  相似文献   
367.
目前对环境污染的治理似乎遗漏了一些有效的方法.根据生态修复的定律以及环境污染的治理模型的函数公式展开了符合逻辑的算法和理论计算案例设计.结果表明优化修复主体利用率在环境污染的生态修复中的作用非同凡响.这类似海绵理论,如果把污染物比喻成水,不同的修复主体就是不同的海绵,我们要提高所有海绵的利用率,让他们吸收更多的“水”,而不是在海绵没有完全利用之前去制造海绵或者减少“水”的产生.这一方法推新了污染治理的思路,现在应该推广研究.  相似文献   
368.
为系统分析导致高处坠落人因事故的产生机理,通过统计152起建筑工程高处坠落事故的调查与分析报告,从组织影响、安全监管、不安全行为前提条件和不安全行为等4个层次,辨识影响高处坠落事故的人为失误因素,修订人为因素分析与分类系统框架(HFACS)。设计高处坠落人因失误调查问卷,开展一线高处作业人员问卷调查,建立高处坠落人因失误结构方程模型,对导致高处坠落事故的人为失误因素进行路径分析。结果表明:各潜在因素间均呈正相关,且高处坠落人因失误事故的关键路径为资源管理不到位→安全监督培训不充分→班组管理不良→操作违规。综合各因素间相关性,提出了针对性的预防高处坠落事故的人因干预策略。  相似文献   
369.
“一带一路”绿色发展的战略实施框架   总被引:1,自引:3,他引:1       下载免费PDF全文
本研究认为推进实施绿色化"一带一路"战略是我国与沿线各国深化经济合作,展示负责任大国形象,规避环境风险,促进顺利实现"五通"的根本要求。同时,我国实施绿色化"一带一路"战略还面临着对外投资的环境管控制度不健全,"一带一路"沿线不少国家和地区生态环境脆弱,环境管理基础弱,以及沿线各国和地区发展阶段及环保诉求不同,区域合作平台与机制不完善等内外因素带来的挑战。本文结合我国实施"一带一路"战略的国际、国内形势研判,提出了推进"一带一路"绿色发展的战略框架,建议加快推进四项重点工作,包括强化绿色发展规划顶层设计,健全风险规制机制,构建对外投资行为调控机制,形成有效的"共通"保障机制。  相似文献   
370.
闫绪娴  范玲  阮嘉珺 《灾害学》2021,(1):7-12,23
经济全球化背景下,各区域的产业关联强度增加,灾害链也日益复杂,对“一带一路”沿线国家及其部门带来了深远的影响。该文梳理了台风灾害损失传导机制,运用多区域投入产出模型(Multiregional Inputoutput Model,MRIO),以2018年“山竹”台风为例,量化分析“一带一路”沿线20个国家24个部门的关联损失情况。研究认为:①2018年“山竹”台风对我国各部门造成的直接损失约为142.31亿元,间接经济损失达到1272.73亿元;②“山竹”台风灾害对沿线其他国家带来的关联损失为1232.13亿元,其中受影响最严重的是菲律宾;③部门关联损失最大的是制造业,其间接损失是直接损失的60倍。  相似文献   
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