全文获取类型
收费全文 | 176篇 |
免费 | 15篇 |
国内免费 | 39篇 |
专业分类
安全科学 | 48篇 |
废物处理 | 8篇 |
环保管理 | 45篇 |
综合类 | 87篇 |
基础理论 | 7篇 |
污染及防治 | 10篇 |
评价与监测 | 17篇 |
社会与环境 | 7篇 |
灾害及防治 | 1篇 |
出版年
2024年 | 4篇 |
2023年 | 8篇 |
2022年 | 8篇 |
2021年 | 14篇 |
2020年 | 20篇 |
2019年 | 7篇 |
2018年 | 3篇 |
2017年 | 11篇 |
2016年 | 11篇 |
2015年 | 9篇 |
2014年 | 11篇 |
2013年 | 20篇 |
2012年 | 13篇 |
2011年 | 13篇 |
2010年 | 1篇 |
2009年 | 9篇 |
2008年 | 10篇 |
2007年 | 6篇 |
2006年 | 9篇 |
2005年 | 4篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 9篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 6篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1978年 | 2篇 |
排序方式: 共有230条查询结果,搜索用时 734 毫秒
51.
Sandy beaches are the prime sites for human recreation and underpin many coastal economies and developments. In many coastal
areas worldwide, beach recreation relies on the use of off-road vehicles (ORVs) driven on the shore. Yet, the use of ORVs
is not universally embraced due to social conflicts with other beach user groups and putative environmental consequences of
vehicle traffic on sandy shores. Such ecological impacts of ORVs are, however, poorly understood for endobenthic invertebrates
of the intertidal zone seawards of the dunes. Consequently, this study quantified the degree to which assemblages of intertidal
beach invertebrates are affected by traffic. The study design comprised a series of temporally replicated spatial contrasts
between two reference sites (no ORVs) and two beaches with heavy ORV traffic (in excess of 250,000 vehicles per year) located
in South-East Queensland, Australia. Macrobenthic assemblages on ORV-impacted beaches had significantly fewer species at substantially
reduced densities, resulting in marked shifts in community composition and structure. These shifts were particularly strong
on the middle and upper shore where vehicle traffic was concentrated. Strong effects of ORVs were detectable in all seasons,
but increased towards the summer months as a result of heavier traffic volumes. This study provides clear evidence that ORVs
can have substantial impacts on sandy beach invertebrates that are manifested throughout the whole community. Demonstrating
such an ecological impact caused by a single type of human use poses a formidable challenge to management, which needs to
develop multi-faceted approaches to balance environmental, social, cultural, and economic arguments in the use of sandy shores,
including management of “beach traffic.” 相似文献
52.
Fayard GM 《Journal of Safety Research》2008,39(1):9-18
PROBLEM: Although parking facilities are a common feature of the landscape in the United States, little is known about their safety. METHOD: A dataset of parking lot fatalities for 1993-2002, created from the Census of Fatal Occupational Injury (CFOI) research file, was analyzed. RESULTS: The most common events in parking lots were contact with objects (15%), pedestrian fatalities (13%), homicides (36%), and suicides (11%). The perpetrators of parking lot fatalities, compared to all workplace homicides, were more likely to be known to the victim. CONCLUSION: The 206 work-related fatalities per year in parking lots present challenges to the safety community. Although much of the risk results from the usage of motor vehicles, violent acts are even more prominent. IMPACT ON INDUSTRY: Because homicides are most prevalent in parking lots, both administrative and environmental measures may lower the risk of homicide. Although difficult to assess, various elements of the design of parking facilities may have an influence on the occurrence of injuries. 相似文献
53.
Charles A. Ambrose Richard Hooper Anthony K. Potter M. Margaret Singh 《Resources, Conservation and Recycling》2002,36(4)
Mechanical recycling of 100% post-consumer plastic waste into high-quality products has been performed. The chemical and physical properties of these recycled materials have been compared with similar products manufactured from virgin resins. The properties of a blow-moulded bottle prepared from 100% post-consumer high-density polyethylene (HDPE) showed that this recycled polymer exceeded the materials specifications for virgin plastic designs. Similarly, a sample of thermoplastic polyolefin (TPO, 100% polypropylene), obtained entirely from shredder residue (SR) displayed sufficient material strength for future separation and reprocessing. 相似文献
54.
在分析城市步行街及其周边存在人车混行、人员密度高、通行效率低、潜在的危险大的基础上,笔者用计算机模拟方法研究了沈阳市中街步行街的一个人车混行的交叉路口,实际勘察了十字路口道路格局、车流、人流状况,测量、估计通过路口的人数、流量,根据获得的数据,对不设置交通信号灯、设置信号灯、建设过街天桥或地下通道等几种情况进行模拟,得到各种情况下的通行效率,并对不同的过街方案的优缺点进行比较。最终选择过街方案需要综合考虑影响安全和效率的多种因素,包括地域、人流量、路口宽度、周边交通等因素,用较小的经济投入取得最大的通行效率。文中的模拟采用EXODUS软件。 相似文献
55.
Assessment of New Vehicles Emissions Certification Standards in the Metropolitan Area of Mexico City 总被引:1,自引:0,他引:1
Light duty gasoline vehicles account for most of CO hydrocarbons and NOx emissions
at the Metropolitan Area of Mexico City (MAMC). In order to ameliorate air pollution from the beginning of 2001, Tier 1 emission standards became mandatory for all new model year sold in the country. Car manufacturers in Mexico do not guarantee the performance of their exhaust emissions systems for a given mileage. The purpose of this study was to assess whether the Tier 1 vehicles will stand the certification values for at least 162000 km with the regular fuel available at the MAMC. Mileage accumulation and deterioration show that certified carbon monoxide emissions will stand for the useful life of the vehicles but in the case of non-methane hydrocarbons will be shorter by 40%, and nitrogen oxides emissions above the standard will be reached at one third of the accumulated kilometers. The effect of gasoline sulfur content, on the current in use Tier 1 vehicles of the MAMC and the impact on the emissions inventory in year 2010 showed that 31000 extra tons of NOx could be added to the inventory caused by the failure of the vehicles to control this pollutant at the useful life of vehicles. 相似文献
56.
57.
58.
To improve the estimation accuracy of battery’s inner state for battery management system, an online parameters identification algorithm for Thevenin battery model is researched. The Thevenin model and parameters identification algorithm based on recursive least square adaptive filter algorithm was built with the Simulink/xPC Target. The results of hardware-in-loop experiment, which uses Federal Urban Driving Schedule test to verify the parameters identification approach, show the proposed approach can accurately identify the model parameters within 1% maximum terminal voltage estimation error, and the State of Charge error which calculated by the open circuit voltage estimates can be efficiently reduced to 4%. 相似文献
59.
2014年9月1日起,国家试行6年以内的非营运轿车等车辆免检制度。大多数城市根据此规定,对于车辆的排放定期检验也同步实施6年免检。随着汽车保有量的快速增长,车辆尾气排放对大气环境的影响不容忽视。因此,地方环保部门应针对机动车污染排放的管理重点,从管理手段、管理体制机制、管理对策等方面进一步加强对高污染车辆的监管。 相似文献
60.
为完善增程式电动汽车(Extended range electric vehicle,EREV)全生命周期环境影响和经济效益评价研究,对EREV、纯电动汽车(Battery electric vehicle,BEV)和内燃机汽车(Internal combustion engine vehicle,ICEV)进行了对比分析.基于生命周期评价理论和生命周期成本分析方法,构建了车辆生命周期资源消耗、能源消耗、环境影响和成本评价模型,针对不同汽车各阶段材料消耗、能源消耗和环境排放三大特性,识别EREV、BEV和ICEV的环境负荷差异,并从初始购置成本、使用维护成本和报废回收成本3个方面评价了EREV、BEV和ICEV的生命周期成本差异.综合碳排放特性和经济属性,进一步提出减碳经济性评价指标,科学评价EREV和BEV的环境效益和减碳经济性,并讨论了不同电力结构下EREV、BEV和ICEV的生命周期温室气体排放情况和减碳经济性变化.对增程式电动汽车进行全生命周期内综合评价研究,进一步明确EREV在多种能源类型汽车技术路线中的环境效益和减碳经济性.结果表明,相比于ICEV,BEV和EREV在运行使... 相似文献