首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1441篇
  免费   100篇
  国内免费   191篇
安全科学   184篇
废物处理   20篇
环保管理   279篇
综合类   567篇
基础理论   317篇
环境理论   2篇
污染及防治   91篇
评价与监测   76篇
社会与环境   135篇
灾害及防治   61篇
  2024年   2篇
  2023年   18篇
  2022年   43篇
  2021年   39篇
  2020年   56篇
  2019年   42篇
  2018年   33篇
  2017年   63篇
  2016年   75篇
  2015年   68篇
  2014年   62篇
  2013年   98篇
  2012年   109篇
  2011年   112篇
  2010年   78篇
  2009年   109篇
  2008年   66篇
  2007年   90篇
  2006年   72篇
  2005年   61篇
  2004年   66篇
  2003年   49篇
  2002年   45篇
  2001年   35篇
  2000年   19篇
  1999年   29篇
  1998年   30篇
  1997年   19篇
  1996年   11篇
  1995年   14篇
  1994年   9篇
  1993年   8篇
  1992年   6篇
  1991年   3篇
  1990年   10篇
  1989年   2篇
  1988年   2篇
  1987年   4篇
  1986年   1篇
  1985年   32篇
  1984年   14篇
  1983年   11篇
  1982年   6篇
  1981年   2篇
  1980年   3篇
  1979年   1篇
  1978年   2篇
  1977年   1篇
  1971年   2篇
排序方式: 共有1732条查询结果,搜索用时 140 毫秒
851.
ABSTRACT

This study investigated whether endorsement of personal values is associated with willingness to pay more for mobile phones with an environmental or social sustainability label. Participants were students in Sweden, Norway and Germany. A self-report inventory was used to measure willingness to pay and the importance attached to values of Schwartz’s circular model. In Sweden and Norway, participants were willing to pay, on average, 18% extra for a mobile phone with labels for environmental or social sustainability. In Germany, the corresponding share was 12%. To strive for self-enhancement values, that is, social status and prestige, as well as control and dominance over people and resources, was associated with a lower willingness to pay for mobile phones with labels for environmental or social sustainability in all three countries. Furthermore, women were willing to pay more than men for mobile phones with both kinds of sustainability labels. In Sweden and Norway, participants were, on average, willing to pay more for a mobile phone with a label for social sustainability compared to a mobile phone with a label for environmental sustainability.  相似文献   
852.
《Environmental Hazards》2013,12(4):379-394
The use of alternatives to evacuation during wildfire events continues to be an intensely debated strategy in the professional and policy circles of numerous fire-prone countries. The most recent chapter comes in response to the Black Saturday Fires in Australia, which has led to policy changes concerning alternatives to evacuation in both Australia and USA. This study explores the local context that influenced the development of alternatives to evacuation in one Idaho community through in-depth interviews with local residents and officials. It acknowledges alternatives as one ‘fire-adaptive behaviour’ of the local community, a key characteristic that US fire professionals identify as a means to better manage wildfire. We apply and extend a recently created adaptive capacity framework for wildfire to uncover specific community characteristics that both led to and reinforce the development of alternatives to evacuation that are tailored to the local population. Identification of these characteristics serves as one important step towards better local assessment of adaptive capacity for a broad classification of ‘fire-adaptive’ behaviours. We conclude that no one combination of local resources can guarantee the development of alternatives to evacuation. Rather, diverse local context will result in different approaches and applicability of the practice.  相似文献   
853.
外来入侵植物在中国的分布及入侵能力研究进展   总被引:3,自引:0,他引:3  
以近十几年来备受关注的外来植物入侵为背景,综述关于入侵植物在我国分布和入侵能力及其相关因素的研究进展,并探讨了未来研究需要加强的几个方面。不同起源地的入侵植物在我国分布区域不一样,在控制了起源地的作用后,入侵植物主要分布在经济较发达、人为活动较多的省份或地区(大尺度),以及干扰较严重的生境(小尺度)。入侵能力强的多年生植物常有强大的无性繁殖能力、高光合速率和资源利用效率、强化感作用、以及适应异质生境的能力;起源于美洲的入侵能力强的1年生植物常能产生大量的易传播的种子、可自交亲和、强化感作用等;起源于欧亚大陆的入侵能力强的1年生植物常与作物非常相似,在农田中危害严重。未来需要研究干扰促进入侵的机制、化感作用与野外实际情况相结合研究、化感物质通过改变土壤微生态环境间接促进入侵的机制研究、1年生和多年生外来植物的入侵能力与其物种特性之间的关系、以及加强对弱入侵性外来植物的预警研究。这些研究不仅能使我们深入理解外来植物发生入侵和危害的规律,也可为人侵植物的防控和管理提供科学依据。  相似文献   
854.
河西绿洲灌区玉米秸秆带膜还田腐解特征研究   总被引:2,自引:0,他引:2  
为探讨河西绿洲灌区玉米秸秆带膜还田时的腐解规律,采用尼龙网袋法,对不同带膜还田模式下玉米秸秆的腐解特征进行研究,旨为当地玉米秸秆还田提供理论依据和技术指导。结果表明:土壤温度是影响当地玉米秸秆腐解的主要因素,经过180 d腐解后,各还田处理秸秆的腐解率均在50%以上,其中翻压处理的腐解率(67.5%~76.0%)高于覆盖处理(50.5%~59.0%),而且腐解主要发生在还田后的30~120 d。秸秆在还田前期(前60 d)会与作物争夺土壤氮素,但是在还田后期会释放一定氮素,而且翻压和粉碎还田释放的氮素要高于覆盖和整株还田。从秸秆完全腐解的预测时间看,整株半量翻压、整株半量覆盖、粉碎半量翻压、粉碎全量翻压、粉碎半量覆盖和粉碎全量覆盖处理分别需要247、326、212、227、277和299 d才能完全腐解,可见,在河西绿洲灌区实行带膜还田前景广阔,而且翻压优于覆盖,粉碎优于整株,半量优于全量。  相似文献   
855.
To explore the factors that influence respondents’ willingness to pay (WTP) for the risk reduction of chemical industry accidents, a questionnaire survey combined with contingent valuation and psychometric paradigm methods were conducted in the city of Yancheng, Jiangsu Province, China. Both traditional socioeconomic variables and perceived characteristics of the hazards were considered in this study, and a Tobit model was used to find the factors influencing WTP under three risk reduction scenarios. The results showed that three demographic characteristics, age, gender, and income, significantly affected the WTP for chemical risk reduction. In addition, three extracted public risk perception factors, effect, knowledge, and trust, also strongly affected the WTP. The mean WTP value increased as the magnitude of the risk reduction increased. The number of factors influencing the WTP decreased as the reduction level improved, and only the effect factor had a significant influence on the WTP for a higher level (80%) of risk reduction. The cost for chemical safety management of Yancheng was calculated, and the optimized risk reduction level was determined. These findings can assist governments and policy makers to formulate suitable strategies for risk control, to reach target groups of people to develop effective communication, and to provide specific references for the best investment for the security of local residents.  相似文献   
856.
江苏省水稻秸秆资源量及其可收集量估算   总被引:15,自引:0,他引:15  
以江苏省23个主要水稻品种为研究对象,对不同品种类型、种植方式和单产水平的水稻进行取样调查,分析不同生产条件下的水稻草谷比及不同留茬高度下的秸秆可收集量,结合相关统计资料估算江苏省水稻秸秆资源量及其可收集量。结果表明,水稻草谷比在不同品种类型间差异较小(0.98~1.03),不同种植方式(0.80~1.19)和不同单产水平(0.83~1.12)间差异较大;当留茬高度为5、15、20和25 cm时,水稻秸秆可收集系数分别为0.815~0.868、0.668~0.732、0.600~0.669和0.533~0.618,水稻秸秆可收集量分别为1 352.16×104~1 458.09×104、1 145.70×104~1 228.13×104、1 043.20×104~1 121.52×104和951.37×104~1 021.30×104 t。估算得到2009年江苏省水稻秸秆资源量(以干质量计)为1 585.93×104~1 704.92×104 t,比传统方法的估算结果高2.45%~10.14%。江苏省水稻秸秆资源丰富,可收集量主要受留茬高度和种植方式的影响。  相似文献   
857.
从支付能力和支付意愿的角度,应用扩展线性支出系统(ELES)模型和条件价值评估法(CVM),定量研究居民生活用水水价承受能力.以广州市番禺区为例,通过2005~2009年截面数据资料和问卷调查数据,定量研究了城镇和农村居民生活用水水价支付能力和支付意愿,并分析了2011年番禺区居民对新调整居民生活用水水价的承受能力.结果表明,2005~2009年,达到平均收入水平的番禺区居民对水价具有支付能力,其基本用水需求能得到满足,但低收入户,尤其是农村低收入户的水价支付能力有限,是水价改革应重点关注的对象;CVM调查结果显示,番禺区居民对2011年生活用水水价的支付意愿为2.163元/m3;2011年,番禺区居民生活用水价格由2.00元/m3上调为2.15元/m3,达到平均收入水平的番禺区居民对新水价具有承受能力.  相似文献   
858.

Aims

A sociological and anthropological view of culture was used to investigate how work culture, independent of “safety culture”, may affect safety in the workplace. We explored how work cultures of nurses and physical/occupational therapists (PT/OTs) in two acute care hospitals are related to the adoption of patient lifting devices.

Methods

Focus groups were conducted between 2006 and 2009, seven with nurse staff (n = 39) and two with PT/OT staff (n = 17), to explore issues concerning a Minimal Manual Lift Environment policy, initiated in 2004, and subsequent use of patient lift equipment. Audio recordings of the sessions were transcribed; text data were analyzed using N6-QSR. Cultural facilitators and barriers to the adoption of patient lift equipment were examined.

Results

Data revealed cultural similarities and differences between these healthcare professions. Both displayed a “patient first” approach to care-giving which may promote lift device use for patients’ benefits, not necessarily for staff safety. Also, the implied purpose of patient lifting devices clashes with the nurses’ cultural emphasis on compassion, and with PT/OTs’ cultural emphasis on independence except when use increases patients’ independence.

Conclusions

Cultural expressions regarding the nature of care-giving among healthcare professionals may affect the propensity to adopt safety measures in complex ways. The workers’ understanding of the purpose of their work, and acceptable means of conducting it, should be understood before implementing safety interventions. The utilization of lift assist teams, who are not socialized into the cultures of nursing or PT/OT, may be one means of circumventing cultural barriers to lift equipment use.  相似文献   
859.
Dynamic disasters can be easily induced by mining disturbance in the tectonic stress concentration region near the fault. Based on the fault Coulomb failure stress criterion, a dynamic Coulomb failure stress increment model is established for quantitative assessment of mining disturbance effect. Furthermore, the disturbance effects of two possible working face arrangements near the same fault are compared by using the proposed dynamic Coulomb failure stress model and numerical method. The results show that Coulomb failure stress increment, as a comprehensive mechanical parameter, can well reflect the mining disturbance to the stress environment of fault. The disturbance effect on the fault in the case of the working face perpendicular to fault is much less than that of the working face parallel to fault, therefore the dynamic disaster risk induced by the former arrangement is much lower.  相似文献   
860.
基于模糊集和改进TOPSIS方法的跑道侵入风险评估   总被引:3,自引:0,他引:3  
为预防民航机场跑道侵入事件的发生,减轻塔台管制员面临的跑道运行安全的压力,根据国际民航组织(ICAO)颁布的《防止跑道侵入手册》描述的空中交通管制(ATC)因素,建立影响跑道侵入的ATC指标评价体系。首先运用模糊集理论建立评价模型,并计算子指标的模糊可能性值,其值反映所论子指标风险概率。其次,采用改进的TOPSIS方法进行验证,并计算子指标的信度效度值。结果表明,得出的子指标风险值与模糊可能性值的排序一致。最后,根据子指标风险值的大小提出防止跑道侵入事件发生的建议。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号