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341.
刘家祥  陈全 《安全》2019,40(5):11-14
为提升企业的安全风险管控水平,以R化工厂的甲醇成品罐区为例,运用系统的危险源辨识方法对其设备、工艺过程、切罐、倒罐操作程序、生产作业活动等进行系统全面的危险源辨识,形成安全风险信息数据库。基于安全风险信息数据库,开发各种风险管控工具。利用信息化技术,构建安全风险管控信息系统,对企业实行动态化的安全管理。  相似文献   
342.
万晓明  王浩杰  张毅  陈志刚  张栋 《安全》2019,40(10):56-59
为了预防企业生产安全事故发生,围绕危险源的管理,综合运用多种安全评价方法,通过小组活动自下而上开展全员危险源辨识、风险评价、现有风险控制措施评估,结合危险源辨识成果随机抽查、行为安全观察等管理活动,形成了企业全员危险源管理的企业文化氛围。对开展全员危险源管理1年以上的13家不同类型企业进行安全文化绩效评估,结果显示,开展THM对安全行为、安全教育、全员参与等安全文化绩效评价指标有显著提升作用。  相似文献   
343.
基于可拓和组合赋权的泥石流危险性评价   总被引:1,自引:0,他引:1  
基于可拓学物元理论,结合层次分析主观赋权法与灰色关联度客观赋权法,对评价因子进行组合赋权,避免单一赋权方法的片面性,建立泥石流危险性评价模型。影响泥石流危险性的因子有很多,通过现场实际调查,选取一次泥石流最大冲出量、发生频率、24 h最大降雨量等8个因子对泥石流进行危险性评价。运用该模型对卡拉地区7条泥石流沟进行危险性评价,评价结果与实际情况相吻合,表明此方法可为泥石流危险性评价提供参考。  相似文献   
344.
天然气管道时常受到破坏,并诱发巨大的射流火焰,可能引燃周围建构物体。系统地分析了管道压力对天然气射流火热辐射灾害的影响,以建立天然气射流火热辐射灾害的系统定量分析方法。基于压力管道小孔泄漏模型和权重-多点源热辐射计算模型,建立了目标物体最大入射热辐射通量、管道压力和目标物与泄漏小孔水平距离的定量关系式。进而选定10 k W/m~2和31.5 k W/m~2作为城镇建筑物遭受引燃和机械破坏的热辐射通量阈值,得到了不同管道压力下天然气射流火热辐射灾害范围。计算结果表明,GB 50028—2006《城镇燃气设计规范》依据管道压力所规定的燃气管道与建筑物的安全间距不能完全满足天然气管道破坏时射流火焰的安全要求,与某武汉天然气管道射流火事故后果一致。  相似文献   
345.
Objectives: The objectives of this study include assessing the motorcycle helmet use pattern in Calicut, India, and analyzing the factors influencing helmet use including motorcyclists' perceptions.

Methods: Field observational studies at 15 locations were conducted to determine the helmet use rate among motorcyclists and pillion passengers. A structured questionnaire interview survey was conducted with 709 motorcyclists to evaluate the users' perceptions and opinions regarding the use of motorcycle helmets.

Results: There was a considerable difference in the level of motorcycle helmet use observed between the locations within and outside the city limits, where different levels of helmet law enforcement were exercised. The helmet use was observed at a maximum of 89% within the city and a minimum of 23% in some locations outside the city. The decreasing percentage of helmet use while moving toward the locations outside the city was confirmed statistically through t tests (t = 1.771, df = 13, P < .05). It was found that only 42% of users revealed that helmets are comfortable and 42% expressed that helmets affect hearing ability. It is important to note that 57% of users are of the opinion that there is no need to use a helmet if you drive slowly and carefully. The price of the helmet was not a deterrent for helmet use. In addition, it was observed that only 45% of helmets used by the motorist were standard helmets with an Indian Standards Institute (ISI) mark.

Conclusion: The widely varying helmet use pattern observed in the study area may be attributed due to the users' behaviors; that is, using a helmet only when the helmet law is strictly enforced rather than using a helmet as a protective device. Further, some of the problems and beliefs associated with helmet use prevent motorcyclists from using a helmet. Hence, the road safety of motorcyclists can be improved only through addressing the identified measures comprehensively.  相似文献   

346.
Objective: Driver sleepiness is a major crash risk factor but may be underrecognized as a risky driving behavior. Sleepy driving is usually rated as less of a road safety issue than more well-known risky driving behaviors, such as drink driving and speeding. The objective of this study was to compare perception of crash risk of sleepy driving, drink driving, and speeding.

Methods: Three hundred Australian drivers completed a questionnaire that assessed crash risk perceptions for sleepy driving, drink driving, and speeding. Additionally, the participants' perceptions of crash risk were assessed for 5 different contextual scenarios that included different levels of sleepiness (low, high), driving duration (short, long), and time of day/circadian influences (afternoon, nighttime) of driving.

Results: The analysis confirmed that sleepy driving was considered a risky driving behavior but not as risky as high levels of speeding (P < .05). Yet, the risk of crashing at 4 a.m. was considered as equally risky as low levels of speeding (10 km over the limit). The comparisons of the contextual scenarios revealed driving scenarios that would arguably be perceived as quite risky because time of day/circadian influences were not reported as high risk.

Conclusions: The results suggest a lack of awareness or appreciation of circadian rhythm functioning, particularly the descending phase of circadian rhythm that promotes increased sleepiness in the afternoon and during the early hours of the morning. Yet, the results suggested an appreciation of the danger associated with long-distance driving and driver sleepiness. Further efforts are required to improve the community's awareness of the impairing effects from sleepiness and, in particular, knowledge regarding the human circadian rhythm and the increased sleep propensity during the circadian nadir.  相似文献   

347.
Aquaculture tenures or leases have become an increasingly important management tool for regulating access rights to coastal and offshore marine habitat. Tenure, as a form of private property rights to marine space, is generally considered a prerequisite for aquaculture development, as are the associated exclusive access rights which provide necessary incentives for producers to invest in infrastructure. The shellfish industry in British Columbia (BC), Canada, is presented as a case study of a transition from a primarily common property wild fishery to a rights‐based system for aquaculture. In BC, seafood production has grown substantially during the past two decades as a result of aquaculture production. However, despite the inherent economic advantages of the tenuring system for increasing seafood production, rights to aquaculture sites in BC remain highly controversial, particularly in response to environmental concerns and infringements on Aboriginal territorial claims. Shellfish farming has, to‐date, been far less controversial than salmon farming; however, shellfish aquaculture has not been uniformly adopted across the province, and analyses of industry capacity or economic opportunities for coastal communities have failed to adequately explain development patterns. This paper, which identifies perceptions of the risks and benefits of the shellfish aquaculture tenuring system, presents the results of 56 interviews conducted with individuals involved in shellfish production in BC. Results indicate that heightened perceptions of risk about shellfish aquaculture tenuring are related to unresolved Aboriginal territorial claims, economic dependence on wild shellfish resources, as well as place‐based values favouring access to wild resources. Underlying values and cultural understandings also strongly shape public perceptions of the risks of aquaculture, and as such, influence local decisions to either accept or resist industry growth. In this case, interviewees' risk perceptions were found to be more important indicators of the potential for industry expansion than studies of capacity or economic cost‐benefit analyses.  相似文献   
348.
通过对旅游者旅游资源环境感知调查、态度分析,能了解旅游者对风景区的满意度,对于促进当地旅游业的可持续发展具有极其重要的作用和意义。以五泉山风景区为例,结合实地问卷调查与访谈的方法,研究旅游者对五泉山风景区的环境感知,结果显示:旅游者对五泉山风景区旅游环境总体环境感知一般;对五泉山风景区的自然环境呈正面、积极感知,但是对饮食服务水平、旅游从业者服务态度、文化特色、环境设施等持保留态度;旅游者对在风景区内的环保责任和行为都表现出了积极的态度;旅游者对景区的忠诚度一般;地方政府在环境保护和旅游规划方面应当更有所作为。  相似文献   
349.
People spend most of their time indoors, where air pollution levels rival and often exceed those outdoors for a number of important pollutants. Yet, little is known about people’s knowledge of indoor environmental hazards. The purpose of the current study was to construct a measure of indoor environmental knowledge. A set of 78 true/false items were developed with input from a panel of experts. The set of items was truncated with traditional item analyses, resulting in a reliable set of 21 items (α = .79). Concurrent validity was established by a significant correlation between the indoor environmental knowledge (IEK) scale and an established measure of science literacy (r = 0.44, p < .001). Schema theory guided the assumption that the two measures should be related. Convergent validity was established by the significant regression of science literacy, formal education in science and math, and status as an engineering student on IEK scale score, accounting for 25% of the variance in the IEK scale score. Future research avenues are proposed and limitations are discussed.  相似文献   
350.
Aging coastal defences around the UK are challenging managers to redesign schemes to be resilient to extreme events and climate change, be cost-effective, and have minimal or beneficial environmental impact. To enable effective design, reduced uncertainty in the assessment of flood risk due to natural variability within the coastal forcing is required to focus on conditions that pose highest threat. The typical UK standard of protection for coastal defences is to withstand a 0.5% annual probability event, historically also known as a 1 in 200 year return period event. However, joint wave-water level probability curves provide a range of conditions that meet this criterion. We examine the Dungeness and Romney Marsh coastal zone, a region of high value in terms of habitat and energy assets, to quantify the uncertainty in flood depth and extent generated by a 0.5% probability event, and to explore which combinations of wave and water levels generate the greatest threat.  相似文献   
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