全文获取类型
收费全文 | 23736篇 |
免费 | 194篇 |
国内免费 | 532篇 |
专业分类
安全科学 | 419篇 |
废物处理 | 1380篇 |
环保管理 | 2860篇 |
综合类 | 4323篇 |
基础理论 | 6320篇 |
环境理论 | 5篇 |
污染及防治 | 5118篇 |
评价与监测 | 1838篇 |
社会与环境 | 2099篇 |
灾害及防治 | 100篇 |
出版年
2022年 | 176篇 |
2021年 | 168篇 |
2020年 | 123篇 |
2019年 | 134篇 |
2018年 | 1765篇 |
2017年 | 1675篇 |
2016年 | 1537篇 |
2015年 | 403篇 |
2014年 | 357篇 |
2013年 | 1001篇 |
2012年 | 964篇 |
2011年 | 2016篇 |
2010年 | 1306篇 |
2009年 | 1216篇 |
2008年 | 1585篇 |
2007年 | 2011篇 |
2006年 | 571篇 |
2005年 | 511篇 |
2004年 | 448篇 |
2003年 | 532篇 |
2002年 | 541篇 |
2001年 | 465篇 |
2000年 | 343篇 |
1999年 | 222篇 |
1998年 | 144篇 |
1997年 | 132篇 |
1996年 | 110篇 |
1995年 | 161篇 |
1994年 | 149篇 |
1993年 | 124篇 |
1992年 | 132篇 |
1991年 | 150篇 |
1990年 | 120篇 |
1989年 | 129篇 |
1988年 | 133篇 |
1987年 | 114篇 |
1986年 | 84篇 |
1985年 | 100篇 |
1984年 | 142篇 |
1983年 | 135篇 |
1982年 | 124篇 |
1981年 | 98篇 |
1980年 | 93篇 |
1979年 | 106篇 |
1978年 | 89篇 |
1977年 | 84篇 |
1976年 | 78篇 |
1975年 | 90篇 |
1974年 | 101篇 |
1965年 | 74篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
H. Ozaki K. Sharma C. Phanuwan K. Fukushi C. Polprasert 《Journal of Material Cycles and Waste Management》2003,5(1):0031-0038
This paper deals with the present scenario of hazardous waste management practices in Thailand, and gives some insights into
future prospects. Industrialization in Thailand has systematically increased the generation of hazardous waste. The total
hazardous waste generated in 2001 was 1.65 million tons. It is estimated that over 300 million kg/year of hazardous waste
is generated from nonindustrial, community sources (e.g., batteries, fluorescent lamps, cleansing chemicals, pesticides).
No special facilities are available for handling these wastes. There are neither well-established systems for separation,
storage, collection, and transportation, nor the effective enforcement of regulations related to hazardous wastes management
generated from industrial or nonindustrial sectors. Therefore, because of a lack of treatment and disposal facilities, these
wastes find their way into municipal wastewaters, public landfills, nearby dump sites, or waterways, raising serious environmental
concern. Furthermore, Thailand does not have an integrated regulatory framework regarding the monitoring and management of
hazardous materials and wastes. In addition to the absence of a national definition of hazardous wastes, limited funding has
caused significant impediments to the effective management of hazardous waste. Thus, current waste management practices in
Thailand present significant potential hazards to humans and the environment. The challenging issues of hazardous waste management
in Thailand are not only related to a scarcity of financial resources (required for treatment and disposal facilities), but
also to the fact that there has been no development of appropriate technology following the principles of waste minimization
and sustainable development. A holistic approach to achieving effective hazardous waste management that integrates the efforts
of all sectors, government, private, and community, is needed for the betterment of human health and the environment.
Received: February 26, 2001 / Accepted: October 11, 2002 相似文献
72.
73.
R.F. Griffiths 《Process Safety and Environmental Protection》1996,74(4):289
74.
R.F. Griffiths 《Process Safety and Environmental Protection》1996,74(4):290
75.
In 1992 a comprehensive health-promotion project was initiated in seven nursing-homes in the Netherlands. This project was designed to implement an ergonomic-educational programme, with the intention of reducing physical workload and to bring about safe working in order to prevent work-related musculoskeletal complaints. After a period of external support, employees of the nursing-homes should be able to proceed with the programme independently. In this paper the content of the programme and its underlying strategies and theories are described. So far, the programme has got off to a good start in all the nursing-homes. Positive effects of the programme could be demonstrated and guidelines and protocols for safe working were introduced. However, it is as yet too early for definitive conclusions to be drawn regarding the aspect of continuity. 相似文献
76.
Davey L. Jones John F. Farrar Kevin K. Newsham 《Water, Air, & Soil Pollution: Focus》2004,4(6):169-175
Amino acids constitute one of the largest inputs of organic nitrogen (N) to most polar soils and have been hypothesized to be important in regulating vegetational succession and productivity in Arctic ecosystems. Our understanding of amino acid cycling in these soils, however, is poor. The aim of this study was to investigate the size and rate of turnover of the amino acid pool in a range of Arctic and Antarctic soils. Our results indicate that in polar soils with either high or low ornithogenic inputs the amino acid pool is small in comparison to the inorganic N pool (NO–3 and NH+4). The free amino acid pool constituted only a small proportion of the total dissolved organic nitrogen (DON) pool in these soils. Here we show that these low concentrations may be due to rapid use by the soil microbial community in both Arctic and Antarctic soils. The turnover of the amino acid pool in soil was extremely rapid, with a half-life ranging from 2 to 24 h, indicating that this N pool can be turned over many hundred times each summer when polar soils are frequently unfrozen. The implications of amino acids in N cycling and plant and microbial nutrition are discussed. 相似文献
77.
Davey L. Jones John F. Farrar Kevin K. Newsham 《Water, Air, & Soil Pollution: Focus》2005,4(6):169-175
Amino acids constitute one of the largest inputs of organic nitrogen (N) to most polar soils and have been hypothesized to be important in regulating vegetational succession and productivity in Arctic ecosystems. Our understanding of amino acid cycling in these soils, however, is poor. The aim of this study was to investigate the size and rate of turnover of the amino acid pool in a range of Arctic and Antarctic soils. Our results indicate that in polar soils with either high or low ornithogenic inputs the amino acid pool is small in comparison to the inorganic N pool (NO? 3 and NH+ 4). The free amino acid pool constituted only a small proportion of the total dissolved organic nitrogen (DON) pool in these soils. Here we show that these low concentrations may be due to rapid use by the soil microbial community in both Arctic and Antarctic soils. The turnover of the amino acid pool in soil was extremely rapid, with a half-life ranging from 2 to 24 h, indicating that this N pool can be turned over many hundred times each summer when polar soils are frequently unfrozen. The implications of amino acids in N cycling and plant and microbial nutrition are discussed. 相似文献
78.
79.
Abedalrazq F. Khalil Mac McKee Mariush Kemblowski Tirusew Asefa 《Journal of the American Water Resources Association》2005,41(1):195-208
ABSTRACT: Water scarcity in the Sevier River Basin in south‐central Utah has led water managers to seek advanced techniques for identifying optimal forecasting and management measures. To more efficiently use the limited quantity of water in the basin, better methods for control and forecasting are imperative. Basin scale management requires advanced forecasts of the availability of water. Information about long term water availability is important for decision making in terms of how much land to plant and what crops to grow; advanced daily predictions of streamflows and hydraulic characteristics of irrigation canals are of importance for managing water delivery and reservoir releases; and hourly forecasts of flows in tributary streams to account for diurnal fluctuations are vital to more precisely meet the day‐to‐day expectations of downstream farmers. A priori streamflow information and exogenous climate data have been used to predict future streamflows and required reservoir releases at different timescales. Data on snow water equivalent, sea surface temperatures, temperature, total solar radiation, and precipitation are fused by applying artificial neural networks to enhance long term and real time basin scale water management information. This approach has not previously been used in water resources management at the basin‐scale and could be valuable to water users in semi‐arid areas to more efficiently utilize and manage scarce water resources. 相似文献
80.