全文获取类型
收费全文 | 1149篇 |
免费 | 8篇 |
国内免费 | 28篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 56篇 |
环保管理 | 147篇 |
综合类 | 98篇 |
基础理论 | 196篇 |
污染及防治 | 405篇 |
评价与监测 | 209篇 |
社会与环境 | 61篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 33篇 |
2022年 | 75篇 |
2021年 | 60篇 |
2020年 | 12篇 |
2019年 | 26篇 |
2018年 | 38篇 |
2017年 | 34篇 |
2016年 | 53篇 |
2015年 | 27篇 |
2014年 | 49篇 |
2013年 | 146篇 |
2012年 | 55篇 |
2011年 | 63篇 |
2010年 | 50篇 |
2009年 | 47篇 |
2008年 | 64篇 |
2007年 | 43篇 |
2006年 | 43篇 |
2005年 | 34篇 |
2004年 | 31篇 |
2003年 | 29篇 |
2002年 | 20篇 |
2001年 | 17篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 4篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1993年 | 5篇 |
1992年 | 7篇 |
1991年 | 8篇 |
1990年 | 3篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1984年 | 2篇 |
1982年 | 5篇 |
1980年 | 2篇 |
1978年 | 4篇 |
1976年 | 6篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1972年 | 3篇 |
1969年 | 5篇 |
1968年 | 4篇 |
1965年 | 2篇 |
1959年 | 2篇 |
1957年 | 3篇 |
1956年 | 2篇 |
排序方式: 共有1185条查询结果,搜索用时 65 毫秒
221.
The activity concentrations of soil samples collected from thirty different locations of Malwa region of Punjab were determined
by using HPGe detector based on high-resolution gamma spectrometry system. The range of activity concentrations of 226Ra, 232Th and 40K in the soil from the studied areas varies from 18.37 Bq kg−1 (Sangrur) to 53.11 Bq kg−1 (Sitoguno), 57.28 Bq kg−1 (Dhanola) to 148.28 Bq kg−1 (Sitoguno) and 211.13 Bq kg−1 (Sunam) to 413.27 Bq kg−1 (Virk Khera) with overall mean values of 35 Bq kg−1, 80 Bq kg−1and 317 Bq kg−1 respectively. The absorbed dose rate calculated from activity concentration of 226Ra, 232Th and 40K ranges between 8.47 and 24.48, 35.68 and 92.38, and 8.74 and 17.11 nGy h−1, respectively. The total absorbed dose in the study area ranges from 58.08 nGy h−1 to 130.85 nGy h−1 with an average value of 79.11 nGy h−1. The calculated values of external hazard index (Hex) for the soil samples of the study area range from 0.35 to 0.79. Since these values are lower than unity, therefore, according
to the Radiation Protection 112 (European Commission. Radiation Protection 112 1999) report, soil from these regions is safe and can be used as a construction material without posing any significant radiological
threat to population. 相似文献
222.
Reddy Yudhistir Ganguly Dipnarayan Singh Gurmeet Prasad Mamidala Harikrishna Arumughan Paneer Selvam Banerjee Kakolee Kathirvel Arumugam Ramachandran Purvaja Ramachandran Ramesh 《Environmental science and pollution research international》2021,28(31):42051-42069
Environmental Science and Pollution Research - Efficient nutrient cycling and adequate sediment bioavailable nutrient supply are considered to be the two most important factors regulating the high... 相似文献
223.
Ojha Ankita Tiwary Dhanesh Oraon Ramesh Singh Pardeep 《Environmental science and pollution research international》2021,28(24):30573-30594
Environmental Science and Pollution Research - Although water occupies 75% of the earth’s surface, only 0.0067% of the total water is available for human activities. These statistics further... 相似文献
224.
Evaluating progress towards environmental sustainability goals can be difficult due to a lack of measurable benchmarks and insufficient or uncertain data. Marine settings are particularly challenging, as stakeholders and objectives tend to be less well defined and ecosystem components have high natural variability and are difficult to observe directly. Fuzzy logic expert systems are useful analytical frameworks to evaluate such systems, and we develop such a model here to formally evaluate progress towards sustainability targets based on diverse sets of indicators. Evaluation criteria include recent (since policy enactment) and historical (from earliest known state) change, type of indicators (state, benefit, pressure, response), time span and spatial scope, and the suitability of an indicator in reflecting progress toward a specific objective. A key aspect of the framework is that all assumptions are transparent and modifiable to fit different social and ecological contexts. We test the method by evaluating progress towards four Aichi Biodiversity Targets in Canadian oceans, including quantitative progress scores, information gaps, and the sensitivity of results to model and data assumptions. For Canadian marine systems, national protection plans and biodiversity awareness show good progress, but species and ecosystem states overall do not show strong improvement. Well-defined goals are vital for successful policy implementation, as ambiguity allows for conflicting potential indicators, which in natural systems increases uncertainty in progress evaluations. Importantly, our framework can be easily adapted to assess progress towards policy goals with different themes, globally or in specific regions. 相似文献
225.
Pravin Kumar Faisal Ahmed Rajesh Kumar Singh Prerna Sinha 《Environment, Development and Sustainability》2018,20(5):2119-2137
This paper analyses the complex interactions among the seventeen sustainable development goals (SDGs) and presents them in a hierarchical framework using interpretive structural modeling technique. The driving and dependence powers of each of these goals have been ascertained to help the developing and least developed countries improve their strategic orientation for a particular goal within a given time frame. This would also help them in prioritizing their resource allocations on a specific SDG by focusing on its hierarchical ranking on one hand and driving and dependence powers on the other. 相似文献
226.
227.
The pollution of the marine environment caused by land-based sources threatens or impairs the health of the ecosystems and the value of human uses of the coastal waters. the Contracting Parties to the Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region agreed to take all appropriate measures to prevent, reduce and control pollution. in the first meeting of the Contracting Parties, the development of a protocol on the control of marine pollution from land-based sources was recommended as a measure to protect the marine environment.
A small group of experts from the Caribbean Region formulated a strategy for controlling land-based sources of marine pollution. Due to the diverse nature, resources and capabilities of the countries comprising the Region, the pollution control strategy suggested by the group of experts included the following techniques or their most appropriate combination: (1) pollution prevention measures, (2) effluent limitations, (3) water quality limitations, (4) environmental planning, and (5) best management practices. the desirable control strategy should be based on a system of discharge permits in the case of point source pollution, which includes effluent and water quality limitations. the technology based effluent limitations could be applied as a short-range strategy to control pollution from industrial and domestic point source discharges. the use of water quality standards could become part of a long-range strategy for controlling point sources. for nonpoint sources, it would be virtually impossible to develop effluent limitations. Thus, the implementation of best management practices and effective environmental planning would be the most reasonable control strategy for non-point sources. However, pollution prevention measures could consist of a “black list” of substances that should be completely banned, and a “grey list” for those that should be strictly limited. These lists should be adopted or appropriately modified for the conditions of the Wider Caribbean Region.
The development of control based on the water quality of the receiving body of water involves the collection and analysis of effluent and ambient data to develop water quality based permit limits and to assess compliance with these permits. Finally, any marine pollution control strategy developed by the countries of the Region should be mutually agreed upon and implemented within a period of ten years from the ratification of a protocol on land-based sources of marine pollution. 相似文献
A small group of experts from the Caribbean Region formulated a strategy for controlling land-based sources of marine pollution. Due to the diverse nature, resources and capabilities of the countries comprising the Region, the pollution control strategy suggested by the group of experts included the following techniques or their most appropriate combination: (1) pollution prevention measures, (2) effluent limitations, (3) water quality limitations, (4) environmental planning, and (5) best management practices. the desirable control strategy should be based on a system of discharge permits in the case of point source pollution, which includes effluent and water quality limitations. the technology based effluent limitations could be applied as a short-range strategy to control pollution from industrial and domestic point source discharges. the use of water quality standards could become part of a long-range strategy for controlling point sources. for nonpoint sources, it would be virtually impossible to develop effluent limitations. Thus, the implementation of best management practices and effective environmental planning would be the most reasonable control strategy for non-point sources. However, pollution prevention measures could consist of a “black list” of substances that should be completely banned, and a “grey list” for those that should be strictly limited. These lists should be adopted or appropriately modified for the conditions of the Wider Caribbean Region.
The development of control based on the water quality of the receiving body of water involves the collection and analysis of effluent and ambient data to develop water quality based permit limits and to assess compliance with these permits. Finally, any marine pollution control strategy developed by the countries of the Region should be mutually agreed upon and implemented within a period of ten years from the ratification of a protocol on land-based sources of marine pollution. 相似文献
228.
ABSTRACT: The SMEMAX transformation, its modified versions and power transformation were applied to 55 long-term records of annual maximum flood flows tested previously for independence, homogeneity and completeness. Even though SMEMAX transformation reduced the coefficient of skewness to near zero for flood data, their distribution was not a true normal distribution. In almost all cases, the coefficient of kurtosis was quite different from 3.0 of the normal distribution. Empirical criteria showed that SMEMAX transformation performed well only for 40 (70 percent) of the 55 stations tested. Its performance level dropped, especially for stations which had both the coefficient of skewness and kurtosis greater than 3.0 and 10.0, respectively. Power transformation was generally better in transforming the flood data to a normal distribution. It performed well for 50 (90 percent) of the 55 stations tested. The coefficient of skewness in case of the data transformed by power transformation was much closer to the zero value than in the case of SMEMAX transformed series. The SMEMAX transformation and its two modified versions yielded identical results when flood frequency analysis was performed. Computationally, all three methods were equally simple and easy to apply for flood frequency analysis. In some cases, the coefficient of kurtosis for the transformed distributions obtained both by SMEMAX and power transformations deviated farther from that for the normal distribution than for the parent distribution. 相似文献
229.
Sustainable technologies for on-site domestic wastewater treatment: a review with technical approach
Sharma Meena Kumari Tyagi Vinay Kumar Singh Nitin Kumar Singh Surya Pratap Kazmi Absar Ahmad 《Environment, Development and Sustainability》2022,24(3):3039-3090
Environment, Development and Sustainability - The rapid population growth has rendered the centralized sewerage systems a non-realistic option in sparsely populated areas, particularly in... 相似文献
230.
Singh Gaurav Kumar A. R. S. Jaiswal R. K. Singh Surjeet Singh R. M. 《Environment, Development and Sustainability》2022,24(10):12311-12339
Environment, Development and Sustainability - Runoff estimation is of immense importance in hydrological analysis for water resource planning and management. The developing countries cannot afford... 相似文献