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121.
10多年来,四川苍溪县结合实际,立足资源优势,因地制宜,不断实践、探索、总结,走出了一条适合山区农村生态脱贫致富的道路,形成了生态脱贫的“苍溪模式”。本文旨在采用生态经济学理论,运用生态工程分析方法,对该模式生态经济的结构、功能进行分析,以探索适合山区农业县生态脱贫的有效途径。  相似文献   
122.
本实验研究了湿式振动纤维栅的一种新型过滤材质——扁平形金属丝带。根据影响除尘性能的因素,分别研究了风速和过滤片数对金属丝带纤维栅的除尘效率和过滤阻力的影响,并从理论上解释了金属丝带纤维栅的过滤阻力增加的原因,提出了一种新型结构的金属丝带纤维栅。矩形金属纤维栅实验结果说明:在一定风速下,随着过滤片数的增加,除尘效率增加。当风速为3.3m/s,过滤片为6片时,全粉尘的除尘效率达99%;呼吸性粉尘的分级效率大于94%,达到了与化学纤维栅相同的水平。过滤阻力随着速度和过滤片数的增加近似呈线性增加。当湿式振动矩形金属纤维栅为6片,风速为3.3m/s时,纤维栅在当量直径为0.074mm和0.109mm时的最大过滤阻力分别为488Pa和500Pa。  相似文献   
123.
皮带运输机的故障原因与安全防范措施   总被引:4,自引:0,他引:4  
重点分析了皮带运输机在生产过程中容易发生故障的原因 ,并针对原因提出了不同的防范措施  相似文献   
124.
Climate change and disaster management   总被引:2,自引:0,他引:2  
Climate change, although a natural phenomenon, is accelerated by human activities. Disaster policy response to climate change is dependent on a number of factors, such as readiness to accept the reality of climate change, institutions and capacity, as well as willingness to embed climate change risk assessment and management in development strategies. These conditions do not yet exist universally. A focus that neglects to enhance capacity-building and resilience as a prerequisite for managing climate change risks will, in all likelihood, do little to reduce vulnerability to those risks. Reducing vulnerability is a key aspect of reducing climate change risk. To do so requires a new approach to climate change risk and a change in institutional structures and relationships. A focus on development that neglects to enhance governance and resilience as a prerequisite for managing climate change risks will, in all likelihood, do little to reduce vulnerability to those risks.  相似文献   
125.
针对皮带输送机运送各种含铁原料(矿粉),导致转运站岗位粉尘质量浓度严重超标的状况,通过不断研究、试验,研制了1种新型除尘装置,使转运站岗位粉尘质量浓度由过去的368 mg/m3降至10 mg/m3以下,解决了转运站扬尘的问题,目前此除尘技术已在济钢铁前区广泛推广应用.  相似文献   
126.
Purpose: This is a study that updates earlier research on the influence of a front passenger on the risk for severe driver injury in near-side and far-side impacts. It includes the effects of belt use by the driver and passenger, identifies body regions involved in driver injury, and identifies the sources for severe driver head injury.

Methods: 1997–2015 NASS-CDS data were used to investigate the risk for Maximum Abbreviated Injury Scale (MAIS) 4 + F driver injury in near-side and far-side impacts by front passenger belt use and as a sole occupant in the driver seat. Side impacts were identified with GAD1 = L or R without rollover (rollover ≤ 0). Front-outboard occupants were included without ejection (ejection = 0). Injury severity was defined by MAIS and fatality (F) by TREATMNT = 1 or INJSEV = 4. Weighted data were determined. The risk for MAIS 4 + F was determined using the number of occupants with known injury status MAIS 0 + F. Standard errors were determined.

Results: Overall, belted drivers had greater risks for severe injury in near-side than far-side impacts. As a sole driver, the risk was 0.969 ± 0.212% for near-side and 0.313 ± 0.069% for far-side impacts (P < .005). The driver's risk was 0.933 ± 0.430% with an unbelted passenger and 0.596 ± 0.144% with a belted passenger in near-side impacts. The risk was 2.17 times greater with an unbelted passenger (NS). The driver's risk was 0.782 ± 0.431% with an unbelted passenger and 0.361% ± 0.114% with a belted passenger in far-side impacts. The risk was 1.57 times greater with an unbelted passenger (P < .10). Seat belt use was 66 to 95% effective in preventing MAIS 4 + F injury in the driver. For belted drivers, the head and thorax were the leading body regions for Abbreviated Injury Scale (AIS) 4+ injury. For near-side impacts, the leading sources for AIS 4+ head injury were the left B-pillar, roof, and other vehicle. For far-side impacts, the leading sources were the other occupant, right interior, and roof (8.5%).

Conclusions: Seat belt use by a passenger lowered the risk of severe driver injury in side impacts. The reduction was 54% in near-side impacts and 36% in far-side impacts. Belted drivers experienced mostly head and thoracic AIS 4+ injuries. Head injuries in the belted drivers were from contact with the side interior and the other occupant, even with a belted passenger.  相似文献   

127.
为了解决皮带输煤暗道运输过程中粉尘污染严重及冬季供暖不足问题,对暗道通风供热系统进行了优化改造研究。以中煤平朔安家岭264输煤暗道为例,基于气固两相流理论,利用CFD模拟方法,对暗道内由风速对悬浮粉尘浓度分布的影响规律进行数值仿真。模拟结果显示:当输煤暗道排尘风速由0.25 m/s升至0.35 m/s时,粉尘浓度降为3.2 mg/m3,暗道最大通风阻力为245.94 Pa,最低换热量747.68 kW。基于数值模拟结果,从3种优化方案中选定一压一抽联合式通风除尘方案进行改造,现场实测除尘效果良好,表明所提出的输煤暗道通风除尘方案具有实践指导意义。  相似文献   
128.
Jason D. Rivera 《Disasters》2020,44(3):548-568
This study focuses on coastal counties in Texas, United States, affected by Hurricane Harvey in 2017 to gauge the influence of individual and contextual characteristics on people's ability to return to normalcy in the short term. Data from a survey conducted by the Kaiser Family Foundation and the Episcopal Health Foundation between October and November 2017 were utilised in the analysis. The paper observes, based on the results of an ordered logistic regression, and contrary to previous work, that age, gender, levels of poverty, and social capital are not significant predictors of a return to normalcy. However, indicators such as whether a person evacuated, if he/she identified as Hispanic/Latino, the extent of damage sustained to one's home, and if one's automobile was damaged or destroyed are shown to affect recovery. A discussion of the potential reasons for these findings is provided as a means of informing future research on disaster recovery.  相似文献   
129.
湿法脱硫石膏脱水系统设备配置及优化   总被引:1,自引:0,他引:1  
石膏脱水系统作为FGD的重要辅助系统,对于吸收塔运行指标、荣液条件、物料平衡、经济运行、副产物综合利用都有重要作用。介绍了湿法脱硫石膏一、二级脱水系统的流程和设备特点,着重分析研究了系统中一级脱水设备、皮带机冲洗系统、滤液水系统、废水旋流设备等的配置、选型和优化方案。  相似文献   
130.
Kim N 《Disasters》2012,36(2):195-211
This paper proposes a simple indicator to measure the exposure to natural disasters for the poor and non-poor population, in order to assess the global and regional trend of natural hazard and poverty. Globally, poor people are two times more exposed to natural disasters than the non-poor in the twenty-first century. The time trend varies across regions, with poor people in East Asia and Pacific being most exposed to natural disasters, followed by those in South Asia and Sub-Saharan Africa. The change of exposure measure over time is decomposed into two factors: a pure exposure change, which could be fuelled by climate change; and a concentration component. The result shows that the total net increase of exposure between the 1970s and the 2000s is driven significantly by the increased concentration of the poor (26 per cent) in disaster-prone areas, whereas the contribution of that factor remains very small for the non-poor (six per cent).  相似文献   
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