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701.
J. S. Mani 《Journal of Coastal Conservation》2001,7(1):23-30
The Chennai coast, an integral part of the east coast of India, extends over ca. 35 km. Over the past 120 yr the coastline
has witnessed both man-made and natural disturbances which led to the destruction of the beach front. The construction of
Madras harbour in 1876, was the prime cause of the degradation of this very sensitive coastal region. Continued growth of
Madras harbour has helped in the natural formation of the wide ‘Marina Beach’, south of the harbour. But the shoreline north
of the harbour suffered the consequences of harbour development activities. The north shore receded by ca. 500 m over the
past 120 yr and received attention from the authorities in the past few decades because of the growing awareness of the conservation
value of the coast. This paper highlights the effects of Madras harbour development on the adjoining coast and on the shortterm
mitigation measures planned and executed by the Government agencies to protect the fragile coastline. In spite of sincere
efforts to protect the coastline, the destruction continues unabated due to various reasons. This paper analyses the facts
and suggests a long-term solution to protect the coastline and to regain the past glory. Feasible and cost effective permanent
measures are identified, construction methods suggested and the advantages that the community can derive from the longterm
solutions are discussed. 相似文献
702.
Delhi is one of the many megacities struggling with punishing levels of pollution from industrial, residential, and transportation
sources. Over the years, pollution abatement in Delhi has become an important constituent of state policies. In the past one
decade a lot of policies and regulations have been implemented which have had a noticeable effect on pollution levels. In
this context, air quality models provide a powerful tool to study the impact of development plans on the expected air pollution
levels and thus aid the regulating and planning authorities in decision-making process. In air quality modeling, emissions
in the modeling domain at regular interval are one of the most important inputs. From the annual emission data of over a decade
(1990–2000), emission inventory is prepared for the megacity Delhi. Four criteria pollutants namely, CO, SO2, PM, and NO
x
are considered and a gridded emission inventory over Delhi has been prepared taking into account land use pattern, population
density, traffic density, industrial areas, etc. A top down approach is used for this purpose. Emission isopleths are drawn
and annual emission patterns are discussed mainly for the years 1990, 1996 and 2000. Primary and secondary areas of emission
hotspots are identified and emission variations discussed during the study period. Validation of estimated values is desired
from the available data. There is a direct relationship of pollution levels and emission strength in a given area. Hence,
an attempt has been made to validate the emission inventory for all criteria pollutants by analyzing emissions in various
sampling zones with the ambient pollution levels. For validation purpose, the geographical region encompassing the study area
(Delhi) has been divided into seven emission zones as per the air quality monitoring stations using Voronoi polygon concept.
Dispersion modeling is also used for continuous elevated sources to have the contributing emissions at the ground level to
facilitate validation. A good correlation between emission estimates and concentration has been found. Correlation coefficient
of 0.82, 0.77, 0.58 and 0.68 for CO, SO2, PM and NO
x
respectively shows a reasonably satisfactory performance of the present estimates. 相似文献
703.
704.
Hakkyong Kim 《Disasters》2014,38(4):846-857
With a view towards suggesting improvements to the official UK Guidance for disaster exercises, this paper critically examines a representative sample of recent disaster management exercises in the United Kingdom to determine how they are planned, conducted and assessed. Personal observations and in‐depth qualitative interviews were used to study three representative multi‐agency disaster exercises in the UK: (1) the Hitachi 395 Evacuation Workshop and Exercise Twin Bore, (2) Exercise Saxon Shore and (3) Exercise Operation Safe Return. The research demonstrates that disaster exercises in the UK generally consist of four main approaches: (1) disaster response and adaptability, (2) building‐block approach, (3) citizen participation and (4) discussion‐based debriefs. While the data demonstrates that each of these approaches has significant merit, it also elucidates key improvements that should be made to the official UK guidance and reflected in future exercises. In particular, the research suggests that the Guidance should highlight the importance of adaptability at the scene of a disaster, advance a building‐block methodology to organising exercises and reiterate the need for better debriefings of volunteer participants. 相似文献
705.
Rigaud S Radakovitch O Nerini D Picon P Garnier JM 《Journal of environmental management》2011,92(9):2201-2210
These last decades, the Berre lagoon (in southeastern France) has been deeply affected since the 1930s by strong inputs of contaminants associated with industrial development and since 1966 by huge inputs of freshwater and silts due to the installation of a hydroelectric power plant. Surveys of the surface sediment contamination have been sparsely performed since 1964 for management and research purposes. These surveys were performed by various laboratories that investigated different chemicals and sampling areas using different analysis protocols. Therefore, the available data are disconnected in time and space and differ in quality. In order to reconstruct coherent time series of sediment contamination from this heterogeneous datasets and to discuss the influences of industrial and hydroelectric discharges we used a statistical approach. This approach is based on Principal Component Analysis (PCA) and Fuzzy clustering analysis on data from one extensive survey realized on surface sediments in 1976. The PCA allowed identifying two geochemical indexes describing the main surface sediment geochemical characteristics. The fuzzy clustering analysis on these indexes allowed identifying sub-areas under the specific influence of industrial or hydroelectric discharges. This allowed us to reconstruct, for each sub-area, a coherent and interpretable long-term time series of sediment contamination from the available database. Reconstructed temporal trends allowed us to estimate: (i) the overall decrease of sediment contamination since the mid-1970 attributed to industrial discharge regulations enacted at this period and (ii) the dilution of the concentrations of sediment bound contaminants induced by the hydroelectric power plant and its associated particulate matter inputs. 相似文献
706.
707.
湘西州低碳经济发展路径研究 总被引:1,自引:0,他引:1
低碳经济已成为区域可持续发展的必然选择,发展低碳经济对湘西州转变发展方式具有重要的现实意义,是提升湘西州经济发展效益、转变发展方式、优化产业结构和抓住发展机遇的需要.针对湘西发展低碳经济面临的制约要素,可从宣传低碳消费理念、调整优化产业结构、构筑低碳技术创新体系、加强低碳人才培样和完善低碳政策体系等方面进行解决. 相似文献
708.
李湖生 《中国安全生产科学技术》2011,7(10):5-10
本文在对中国、美国、英国、澳大利亚、爱尔兰等国政府部门或咨询机构发布的大量应急准备规划相关的规范性指导文件的收集与分析的基础上,对这些国家在应急规划的分级分类、政策指导、规划过程、理论基础和规划工具等方面的情况进行了比较研究,分析了目前中国应急准备规划中存在的一些问题和需求。研究表明成熟的规划理论,符合国情的分级分类方法,规范的规划过程,具体详实、实用的指导文件和规划工具,是做好应急准备规划的基础。研究结果可为建立和完善中国应急准备规划体系及其理论与方法提供有益的启示和参考。 相似文献
709.
为评估毫米波云雷达及激光云高仪的探测性能,选取广州市气象局KA波段毫米波云雷达和激光云高仪云高观测数据,通过对比两种测云设备在相同条件下的差异,分析不同要素对观测设备的影响,结果表明:(1)毫米波云雷达与激光云高仪同时探测到有云时,二者在云底高度观测上吻合程度较高,相关系数为0.98;(2)在数据获取率上,云雷达对高云的探测能力明显优于激光云高仪,但在对低云的探测能力上还有待提高,和激光云高仪相比,云雷达对低云和中云的识别能力有待提高;(3)对于多层云的观测,低层云的遮挡降低了激光云高仪对中高层云的观测,激光云高仪探测的中高层云多数在云雷达的回波内部.(4)对于不同强度的降水,日降水量越多,该天所测得的高、中云层回波就越少.(5)通过边界层高度与污染物的关系分析可以得出,边界层高度与PM2.5浓度呈反比.这些研究能够对毫米波云雷达和激光云高仪的探测能力进行评估,为后续选择设备提供参考,也推动了云观测技术的发展. 相似文献
710.
Matteo Vizzarri Ugo Chiavetta Giovanni Santopuoli Daniela Tonti Marco Marchetti 《Journal of Environmental Planning and Management》2015,58(8):1454-1478
In last decades, numerous efforts have been carried out by the scientific community to assess the multifunctional role of forests in supporting the forest decision-making processes. Recently developed in Italy, the Forest Landscape Management Planning seems to be the most suitable tool to maintain the sustainability balance between forests and local populations. This research identifies and maps different forest ecosystem functions in a mountain Natura2000 Network site by performing a spatial estimation of forest inventory parameters, and implementing a multi-criteria and multi-level approach. Final results on mapping of forest functions show acceptable values of classification accuracy. 相似文献