全文获取类型
收费全文 | 1390篇 |
免费 | 105篇 |
国内免费 | 364篇 |
专业分类
安全科学 | 266篇 |
废物处理 | 7篇 |
环保管理 | 111篇 |
综合类 | 734篇 |
基础理论 | 419篇 |
环境理论 | 1篇 |
污染及防治 | 95篇 |
评价与监测 | 41篇 |
社会与环境 | 137篇 |
灾害及防治 | 48篇 |
出版年
2024年 | 7篇 |
2023年 | 23篇 |
2022年 | 47篇 |
2021年 | 70篇 |
2020年 | 66篇 |
2019年 | 60篇 |
2018年 | 62篇 |
2017年 | 70篇 |
2016年 | 78篇 |
2015年 | 82篇 |
2014年 | 72篇 |
2013年 | 184篇 |
2012年 | 85篇 |
2011年 | 99篇 |
2010年 | 85篇 |
2009年 | 70篇 |
2008年 | 69篇 |
2007年 | 81篇 |
2006年 | 75篇 |
2005年 | 58篇 |
2004年 | 49篇 |
2003年 | 54篇 |
2002年 | 44篇 |
2001年 | 39篇 |
2000年 | 33篇 |
1999年 | 32篇 |
1998年 | 19篇 |
1997年 | 13篇 |
1996年 | 8篇 |
1995年 | 36篇 |
1994年 | 25篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 10篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有1859条查询结果,搜索用时 484 毫秒
601.
评析国内外以第一代人因可靠性分析(静态)、第二代人因可靠性分析(动态)为主体形成的人误防范理论和方法;针对目前不能量化人的生理、认知、心理等相关非结构性和非确定性参数和数据的"瓶颈",建立基于人-机-环系统业务流程的人误系统复合状态(Multiplex State ofHumanErrors System,MSHES)结构模型;探求运用粗糙集数据挖掘,对资深专业人员的经验规则信息、人因事故或事件分析的信息,挖掘人因层次结构中的根因与人误层次结构中的差错之间的关联关系,构建基于规则的人误防范专家系统结构模型;探究人的风险性评估和人误防范理论。 相似文献
602.
Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin (NHFS) was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No. 16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein (KU: keratinase unit). Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40℃ to 55℃. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development. 相似文献
603.
Bisphenol A (BPA) is a chemical with high production volume and wide applications in many industries. Although BPA is known
as an endocrine disruptor, its toxic mechanisms have not been fully characterized. Due to its structural similarity to thyroid hormones
thyroxine (T4) and triiodothyronine (T3), one possible mechanism of BPA toxicity is disruption of hormone transport by competitive
binding with the transport proteins. In this study, the binding interactions of BPA, T4, and T3 with three thyroid hormone transport
proteins, human serum albumin (HSA), transthyretin (TTR), and thyroxine-binding globulin (TBG) were investigated by fluorescence
measurement. Using two site-specific fluorescence probes dansylamide and dansyl-L-proline, the binding constants of BPA with HSA
at drug site I and site II were determined as 2.90 104 and 3.14 104 L/mol, respectively. By monitoring the intrinsic fluorescence
of tryptophan, a binding constant of 4.70 103 L/mol was obtained. Similarly, by employing 8-anilino-1-naphthalenesulfonic acid as
fluorescence probe, the binding a nity of BPA with TTR and TBG was measured to be 3.10 105 and 5.90 105 L/mol, respectively.
In general, BPA showed lower binding a nity with the proteins than T3 did, and even lower a nity than T4. Using these binding
constants, the amount of BPA which would bind to the transport proteins in human plasma was estimated. These results suggest that
the concentrations of BPA commonly found in human plasma are probably not high enough to interfere with T4 transport. 相似文献
604.
605.
606.
Mina Zamand 《Environmental Hazards》2016,15(3):246-268
This study attempts to assess the impact of two different climatic shocks, drought and excessive rainfall/flood, as perceived by households on child human capital across four countries: Ethiopia, India, Peru and Vietnam – countries with diverse socio-economic backgrounds. Human capital, in this context, subsumes both child learning and health outcomes. The data source is the Young Lives Study and cross-sectional household data on the older cohort of children (between 14 and 16 years of age) are utilized, for the year 2009. The enrolment rate, Peabody Picture Vocabulary Test, Cloze test and Math test scores are used as proxies for child learning outcomes. The health outcome variables being studied are the WHO-defined Body Mass Index z-scores and Height for Age z-scores. The overall objective is to study heterogeneity in responses to shock in terms of the development of human capital across the set of countries considered. Additionally, the study elaborates on the role of institutional help, during crisis, and the role of household characteristics in buffering these climatic shocks. 相似文献
607.
地勘行业是矿产资源开发的龙头,对国民经济的发展具有重要的作用。通过对地勘行业人因失误的类型和影响因素进行分析,从而提出了相应的管理对策,对加强地勘行业的安全管理,促进地勘经济的长足发展具有重要的意义。 相似文献
608.
基于人体健康风险的水污染事件遗传性致癌物安全浓度研究 总被引:1,自引:0,他引:1
确定水污染事件中遗传性致癌物短期暴露安全浓度,是目前我国水环境管理中急需解决的问题.在假设遗传性致癌物暴露剂量与致癌风险呈线性相关的前提下,提出了水体中遗传性致癌物安全浓度计算流程,建立了采用遗传性致癌物终生暴露安全浓度计算短期暴露安全浓度的方法.在我国2000~2010年间发生的60起水污染事故中,特征污染物为砷的水污染事件为6起,占总污染事件比例为10%,这一结果表明砷为我国水污染事件中高发的特征污染物.根据水污染事件遗传性致癌物短期暴露安全浓度计算方法,得出砷短期暴露安全浓度为0.5 mg.L-1,表明该方法在水污染事件应急管理中具有一定的可行性. 相似文献
609.
Abstract In this paper, human capital is considered a kind of goods in terms of investment. Basic consumption and profit margin are the two important components of human capital goods value. Compared with that of the material capital, the human capital consumption has the following features. The importance of human capital investment determined by the supply-demand mechanism, is growing gradually; The course of investment and return takes a long period of time; Human capital is characterized by strong technicality and weak negotiability; The investment profit margin is changeable and discriminating. 相似文献
610.
This paper explores, explains and discusses issues around the dilemma between local conservation of natural resources (often, endangered species and habitats) and tourism needs in Africa. Often and in constitutional terms, local people have a right to exploit and use resources endowed in their local area. However, tourists often are interested in viewing the vegetation and animal resources undisturbed. Inevitably, there is an undeclared animosity of values and interests between local communities and tourists and state agencies. As a result, the dilemma is thus of governance. The purpose of this paper is to demonstrate the governance dilemma of resource utilization and tourism in Africa in a bid to create an informed stewardship framework for sustainability. This is achieved by way of case studies and narratives from Africa. As such, this paper will be a review literature on how different communities perceive tourism and derive livelihoods from their immediate environment. It also explains how the external factors influence local needs and interests. A more sustainable and operational framework that reduces friction among stakeholders is suggested. 相似文献