全文获取类型
收费全文 | 903篇 |
免费 | 15篇 |
国内免费 | 46篇 |
专业分类
安全科学 | 60篇 |
废物处理 | 13篇 |
环保管理 | 236篇 |
综合类 | 277篇 |
基础理论 | 70篇 |
污染及防治 | 144篇 |
评价与监测 | 86篇 |
社会与环境 | 41篇 |
灾害及防治 | 37篇 |
出版年
2024年 | 3篇 |
2023年 | 9篇 |
2022年 | 15篇 |
2021年 | 26篇 |
2020年 | 32篇 |
2019年 | 15篇 |
2018年 | 15篇 |
2017年 | 26篇 |
2016年 | 37篇 |
2015年 | 20篇 |
2014年 | 38篇 |
2013年 | 34篇 |
2012年 | 41篇 |
2011年 | 85篇 |
2010年 | 31篇 |
2009年 | 64篇 |
2008年 | 75篇 |
2007年 | 48篇 |
2006年 | 48篇 |
2005年 | 22篇 |
2004年 | 32篇 |
2003年 | 29篇 |
2002年 | 23篇 |
2001年 | 20篇 |
2000年 | 24篇 |
1999年 | 22篇 |
1998年 | 12篇 |
1997年 | 19篇 |
1996年 | 12篇 |
1995年 | 12篇 |
1994年 | 16篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1973年 | 2篇 |
排序方式: 共有964条查询结果,搜索用时 181 毫秒
231.
在前人评估重点研究公共消防基础、灭火救援力量的基础上,增加消防安全形势、火灾防控工作对城市消防安全影响因素的研究,以海南某沿海城市为例,采用层次分析法构建城市消防安全评估体系,设置定量化评分判定基准,运用模糊集值统计法计算得分。评估结果表明体系更真实地反映了该市消防安全现状及火灾防控薄弱环节,最后针对高风险项提出具体改进措施。该体系模型丰富了评估指标数量;宏观考虑了该市热带气候、旅游型城市特征、火灾情况对消防安全形势的影响;更重要的是,提出将社会面火灾防控工作纳入评估体系。研究对于城市消防安全评估的宏观化、系统化、地域化、实用化、定量化都有一定参考意义。 相似文献
232.
Whether a city develops into a more compact one with a higher density or a more sprawling one may affect multiple aspects of the urban environment, including ecosystem health, greenhouse gas emissions, and quality of life. Using panel data gathered from China's cities from 2000 to 2010, we take advantage of the significant variation in the temporal change of density across cities to estimate the relationship between gross urban population density and multiple indicators of urban greenness. Fixed‐effects estimates support the widely held belief that density improves air quality and reduces the per capita carbon footprint. Results also suggest that higher density reduces the growth of road infrastructure and vehicle ownership and promotes walking. While density often translates into proximity and accessibility, higher density does reduce a city's per capita urban park and green space. This study strengthens the urban policy and planning literature with much needed longitudinal evidence. Our overall findings support higher density as opposed to lower density urban development in China. 相似文献
233.
234.
235.
常亮 《铁路节能环保与安全卫生》2021,(1):13-17
随着城市的发展,轨道交通在各大城市中得到迅速发展,但与之相伴的环境振动问题也日益突显.为研究城市轨道交通地下线列车运行速度、线路条件、减振措施等运营条件对环境振动影响,在某地铁线路隧道内进行了环境振动源强测试.结果表明,隧道壁源强位置处Z振级随着速度的增加而增大,列车通过速度在57~75 km/h变化时,列车速度每增加... 相似文献
236.
基于分形理论的皖江城市带城镇体系结构研究 总被引:5,自引:0,他引:5
运用分形理论对皖江城市带城镇体系的规模分布和城镇空间结构进行了具体分析,得出如下结论:在城镇规模分布方面,城市规模结构分布较为集中,中等位序的城市较多,首位城市作用不显著,人口分布低水平均衡;在城镇空间结构方面,城镇之间的空间关联程度、空间相互作用一般,空间布局较分散。在此基础上,提出了未来皖江城市带城镇体系发展的相应对策。 相似文献
237.
Manolis Mandalakis 《Environmental pollution (Barking, Essex : 1987)》2009,157(4):1227-1233
Ambient concentrations, gas/particle partitioning and particle-size distribution of polybrominated diphenyl ethers (PBDEs) were investigated in two urban areas (Athens and Heraklion) of Greece. Atmospheric (gas + particle) concentrations of ∑PBDE varied from 21 to 30 pg m−3 in the center of Athens and from 4 to 44 pg m−3 in the suburbs of Heraklion. A predominance of particulate PBDEs was observed in Athens (71-76% in particles), whereas the opposite was evident in Heraklion (69-92% in gas phase). In both urban areas, PBDE particle-size distribution featured a distinct enrichment in smaller particles. A similar trend was also observed in aerosols of a background marine site. For all sampling sites, more than 46% of ∑PBDE was associated with particles of <0.57 μm in diameter. Our results imply that particulate PBDEs may have long atmospheric residence time and they may be capable of reaching the deeper parts of the human respiratory system. 相似文献
238.
Stefan Norra 《Environmental science and pollution research international》2009,16(5):539-545
Background, aim, and scope In 1875, the geoscientist Walter Suess introduced several spheres, such as the lithosphere and the atmosphere to promote a
comprehensive understanding of the system earth. Since then, this idea became the dominating concept for the understanding
of the distribution of chemical elements in the system earth. Meanwhile, due to the importance of human beings on global element
fluxes, the term anthroposphere was introduced. Nevertheless, in face of the ongoing urbanization of the earth, this concept
is not any more adequate enough to develop a comprehensive understanding of global element fluxes in and between solid, liquid,
and gaseous phases. This article discusses a new concept integrating urbanization into the geoscientific concept of spheres.
Main features No geological exogenic force has altered the earth’s surface during the last centuries in such an extent as human activity.
Humans have altered the morphology and element balances of the earth by establishing agrosystems first and urban systems later.
Currently, urban systems happen to become the main regulators for fluxes of many elements on a global scale due to ongoing
industrial and economic development and a growing number of inhabitants. Additionally, urban systems are constantly expanding
and cover more and more former natural and agricultural areas. For nature, urban systems are new phenomena, which never existed
in previous geological eras. The process of the globe’s urbanization concurrently is active with the global climate change.
In fact, urban systems are a major emitter for climate active gases. Thus, beside the global changes in economy and society,
urbanization is an important factor within the global change of nature as is already accepted for climate, ecosystems, and
biodiversity.
Results Due to the fact that urbanization has become a global process shaping the earth and that the urban systems are globally cross-linked
among each other, a new geoscientific sphere has to be introduced: the astysphere. This sphere comprises the parts of the
earth influenced by urban systems. Accepting urbanization as global ongoing process forming the astysphere comprehensively
copes with the growing importance of urbanization on the creation of present geologic formations.
Discussion Anthropogenic activities occur mainly in rural and urban environments. For long lasting periods of human history, human activities
mainly were focused on hunting and agriculture, but since industrialization, urbanized areas became increasingly important
for the material and energy fluxes of earth. Thus, it seems appropriate to classify the anthroposphere into an agriculturally
and an urban-dominated sphere, which are the agrosphere (Krishna 2003) and the astysphere (introduced by Norra 2007).
Conclusions We have to realize that urban systems are deposits, consumers, and transformers of resources interacting among each other
and forming a network around the globe. Since the future of human mankind depends on the sustainable use of available resources,
only a global and holistic view of the cross-linked urban systems forming together the astysphere provide the necessary geoscientific
background understanding for global urban material and energy fluxes. If we want to ensure worth-living conditions for future
generations of mankind, we have to develop global models of the future needs for resources by the global metasystem of urban
systems, called astysphere.
Perspectives The final vision for geoscientific research on the astysphere must be to design models describing the global process of urbanization
of the earth and the development of the astysphere with respect to fluxes of materials, elements, and energy as well as with
respect to the forming of the earth’s face. Besides that, just from the viewpoint of fundamental research, the geoscientific
concept of spheres has to be complemented by the astysphere if this concept shall fully represent the system earth.
相似文献
Stefan NorraEmail: |
239.
K.M. Thiessen K.G. Andersson B. Batandjieva J.-J. Cheng W.T. Hwang J.C. Kaiser S. Kamboj M. Steiner J. Tomás D. Trifunovic C. Yu 《Journal of environmental radioactivity》2009
The Urban Remediation Working Group of the International Atomic Energy Agency's EMRAS (Environmental Modelling for Radiation Safety) program was organized to address issues of remediation assessment modelling for urban areas contaminated with dispersed radionuclides. The present paper describes the second of two modelling exercises. This exercise was based on a hypothetical dispersal of radioactivity in an urban area from a radiological dispersal device, with reference surface contamination at selected sites used as the primary input information. Modelling endpoints for the exercise included radionuclide concentrations and external dose rates at specified locations, contributions to the dose rates from individual surfaces, and annual and cumulative external doses to specified reference individuals. Model predictions were performed for a “no action” situation (with no remedial measures) and for selected countermeasures. The exercise provided an opportunity for comparison of three modelling approaches, as well as a comparison of the predicted effectiveness of various countermeasures in terms of their short-term and long-term effects on predicted doses to humans. 相似文献
240.
K.G. Andersson T. Mikkelsen P. Astrup S. Thykier-Nielsen L.H. Jacobsen S.C. Hoe S.P. Nielsen 《Journal of environmental radioactivity》2009,100(12):1005-1011
The ARGOS decision support system is currently being extended to enable estimation of the consequences of terror attacks involving chemical, biological, nuclear and radiological substances. This paper presents elements of the framework that will be applied in ARGOS to calculate the dose contributions from contaminants dispersed in the atmosphere after a ‘dirty bomb’ explosion. Conceptual methodologies are presented which describe the various dose components on the basis of knowledge of time-integrated contaminant air concentrations. Also the aerosolisation and atmospheric dispersion in a city of different types of conceivable contaminants from a ‘dirty bomb’ are discussed. 相似文献