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51.
This paper examines what organizations and groups individuals rely on to help prepare for natural disasters and how reliance differs vis-à-vis demographic characteristics. Using data gathered from 2,008 individuals employed in the United States, the results revealed that individuals are significantly more likely to rely on friends and family than government organizations at the local, state, and federal level. The findings also suggest that this reliance varies across demographic groups. For example, data from the present study suggest that women and minority groups as well as individuals who are older and less educated are significantly more likely to rely on organizations to help prepare for natural disasters. This study contributes to the disaster management and risk communication literatures by offering key insights into the organizations and groups the American public in general, and certain demographic groups in particular, rely on when it comes to preparing for natural disasters. Knowledge about the organizations and groups that individuals rely on to help prepare for natural disasters can help policymakers and practitioners target those organizations as conduits to deliver critical preparedness information, as well as other information related to disaster mitigation, response, and recovery.  相似文献   
52.
中国农地经营规模对农业劳动生产率的影响及其区域差异   总被引:10,自引:3,他引:7  
农业劳动生产率偏低依旧是中国农业发展的瓶颈,它关系着农民增收和农业发展,提高劳动生产率迫在眉睫。在土地规模不断集中已成为顶层设计基本共识的前提下,理清农地经营规模与劳动生产率之间的关系尤为重要。基于此,论文利用2000-2013年中国大陆31个省份的面板数据,通过理论推断与实证检验,对劳动生产率与农地经营规模的关系进行了定量分析。结果表明:从全国、不同地貌及三大经济带来看,劳动生产率与农地经营规模之间均存在鲜明的“倒L型”关系,即初始阶段,扩大农地经营规模能显著提高劳动生产率,但区域间差异明显,后期劳动生产率会稳定在某一状态。当前,农地规模远小于人均农地的最优经营规模,农地规模的集中是提高劳动生产率的重要举措,推进发展适度规模经营的政策仍有较大的操作空间。政府需要做的是,降低土地流转的交易成本,推动实现多种形式的农地适度规模经营,并兼顾不同区域的差异。  相似文献   
53.
Disaster scholarship shows that people’s relationships stay the same or improve after natural disasters and become worse after technological, or human-induced, events. Using the case of Katrina, this research explores what happens to people’s relationships after a disaster that began with a catastrophic natural event and was followed by numerous failures in the way human institutions responded to the event. Through an analysis of survey data collected in devastated areas of Louisiana and Mississippi in 2008, this study tests how consequences of both natural (damage to the home and having to leave the home) and technological events (distrust in government, stress, concern about toxic exposure, and pursuing litigation) affect people’s relationships with family members and community groups. Damage to the home, distrust in government, and the pursuit of litigation lead to declines in people’s relationships. These experiences are more likely to change intimate relationships (with family) than relationships in the broader community. The relevance that these findings have for creating better social justice outcomes after future disasters is discussed.  相似文献   
54.
The dual goals of the Organic Act of 1916 and Wilderness Act of 1964 are to protect natural resources and provide quality visitor experiences. Park managers need metrics of trail conditions to protect park resources and quality of visitor experiences. A few methods of sampling design for trails have been developed. Here, we describe a relatively new method, spatially balanced sampling, and compare it to systematic sampling. We evaluated the efficiency of sampling designs to measure recreation-related impacts in Rocky Mountain National Park. This study addressed two objectives: first, it compared estimates of trail conditions from data collected from systematic versus spatially balanced sampling data; second, it examined the relationship between sampling precision and sampling efficiency. No statistically significant differences in trail condition were found between the 100-m interval and the spatially balanced datasets. The spatially balanced probability-based dataset was found to be a good estimate of trail conditions when analyses were conducted with fewer sample points. Moreover, spatially balanced probability-based sampling is flexible and allows additional sample points to be added to a sample.  相似文献   
55.
研究了广东省几个主栽甘蔗品种的肥料效应,提出广东省甘蔗专用BB肥的适宜配肥比例为N:P2O5:K2O=1:0.30:0.78-1.00.在中等肥力土壤上,高产甘蔗推荐施肥量为甘蔗专用BB肥1140-1410kg/hm2.施用甘蔗专用BBe肥具有极显著的增产效益,其肥效优于通用型复合肥(15-15-15)和当地肥料,单位面积投肥成本低,经济效益高.  相似文献   
56.
The Klippel-Trenaunay-Weber syndrome is a complex developmental disorder of the vascular and skeletal systems. While many features of the syndrome are congenital, it has not been diagnosed often before birth. This paper describes a case of Klippel-Trenaunay-Weber syndrome diagnosed at 19 weeks' gestation on the basis of sonographic findings and family history. The clinical variability of the syndrome is emphasized and the importance of family history in differential diagnosis is stressed.  相似文献   
57.
木兰科植物在园林中的开发与利用   总被引:8,自引:0,他引:8  
木兰科(Magnoliaceae)植物是原始的被子植物,具有很高的观赏价值。本文从对其种群保护,在园林绿化中的优势以及栽培管理等方面入手,探讨了木兰科植物在园林中的开发与利用的意义及前景。得出木兰科植物完全能符合园林绿化及景观建设的需要。应该大力进行开发与利用。  相似文献   
58.
基于复式记账的自然资源资产负债表平衡关系研究   总被引:3,自引:1,他引:2  
何利  沈镭  陶建格  钟帅  张悦 《自然资源学报》2018,33(10):1697-1705
自然资源资产负债表的平衡关系研究是编制自然资源资产负债表和开展自然资源核算的理论基础。由于对自然资源产权关系和价值活动认识的不一致,对于自然资源资产负债表平衡关系的认识存在不同,也导致了自然资源资产负债表编制工作长期陷入争议状态。对于《环境经济核算体系2012:中心框架》(System of Environmental-Economic Accounting 2012,SEEA 2012)的“期初+增加-减少=期末(期初-减少=期末-增加)”四柱平衡基本认识一致,但对于“资产=权益”、自然资源负债的确认等是否列入编制自然资源负债表的框架存在较多争议。自然资源相关研究的学者较多认为应基于SEEA 2012的“期初+增加-减少=期末(期初-减少=期末-增加)”四柱平衡编制自然资源资产负债表,并分别编制自然资源资产表、负债表,报表基于统计调查结果列示,因此严格意义上也无法称之为自然资源资产负债表,准确说应该称之为自然资源统计报表;会计学界相关研究的学者较多认为应基于“资产=负债+权益”编制自然资源资产负债表,采用会计学复式记账进行核算,但由于对自然资源属性认识存在差异,部分学者提出的“资产-负债=净资产”的概念理解也不统一,没有学者据此设计自然资源复式记账的过程核算体系。论文基于资源科学和会计学理论的交叉研究成果,以资源产权属性和价值属性为基础,构建了自然资源资产负债表的框架体系,明确自然资源资产负债表采用复式记账,对自然资源资产负债表的静态平衡关系和动态平衡关系进行了研究。基于复式记账的自然资源资产负债表静态平衡关系总体表示为“资产=权益”,这是借贷记账的理论基础;动态平衡关系表示为:“期初+增加-减少=期末(期初-减少=期末-增加)”、“入-出=余”,这是进行自然资源资产核算的理论基础。论文进一步分析了基于复式记账的自然资源核算体系恒等式及自然资源资产负债表的框架。  相似文献   
59.
We consider the selection of samples in ranked set sampling when several attributes of each sample are of interest. We describe approaches that have appeared previously in the literature and present a novel method that seeks to achieve samples that are nearly balanced with respect to the ranks of all attributes. This method is shown to result in very little loss of precision compared to problems in which only a single sample attribute is of interest.  相似文献   
60.
随着中国发展方式转变与能源结构转型的深入推进,能源消耗“双控”与燃煤替代供热清洁化、集中化成为必然趋势。清洁供暖效益评价研究是一个动态的系统性问题,涉及技术、财务、经济和社会评价等方面。目前,有关供热模式评价一般集中在经济和技术视角,难以系统反映经济社会、环境资源等深层次问题。以空气源热泵、燃气锅炉和浅层地热能为主多能互补的供暖方案为评价对象,采用系统评价的方法,基于DPSIR模型构建清洁能源供暖综合效益评价指标体系,利用AHP-POS灰色关联度模型定量评价西安市商业建筑清洁能源供暖方案综合效益和D-P-S-I-R子系统的影响作用。结果表明:在经济、技术和投资环境等条件允许情况下,应优先实施以浅层地热能为主的多能互补供暖方案,依次实施煤改电和煤改气方案。进而提出关中地区清洁能源供暖监管体系对策建议,以供决策者和投资者参考。  相似文献   
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