全文获取类型
收费全文 | 896篇 |
免费 | 7篇 |
国内免费 | 109篇 |
专业分类
安全科学 | 50篇 |
废物处理 | 23篇 |
环保管理 | 177篇 |
综合类 | 325篇 |
基础理论 | 167篇 |
环境理论 | 1篇 |
污染及防治 | 183篇 |
评价与监测 | 48篇 |
社会与环境 | 38篇 |
出版年
2023年 | 24篇 |
2022年 | 26篇 |
2021年 | 16篇 |
2020年 | 23篇 |
2019年 | 29篇 |
2018年 | 18篇 |
2017年 | 26篇 |
2016年 | 39篇 |
2015年 | 47篇 |
2014年 | 44篇 |
2013年 | 62篇 |
2012年 | 37篇 |
2011年 | 107篇 |
2010年 | 49篇 |
2009年 | 74篇 |
2008年 | 77篇 |
2007年 | 73篇 |
2006年 | 34篇 |
2005年 | 32篇 |
2004年 | 20篇 |
2003年 | 19篇 |
2002年 | 19篇 |
2001年 | 19篇 |
2000年 | 14篇 |
1999年 | 7篇 |
1998年 | 17篇 |
1997年 | 11篇 |
1996年 | 9篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 7篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有1012条查询结果,搜索用时 15 毫秒
351.
352.
分别用粉状活性炭、粒状活性炭和粘胶基活性炭纤维处理污水处理厂出水,通过对水中COD、氨氮、浊度、pH值等指标进行对比实验,初步研究结果表明,活性炭纤维的吸附速率最快,达到吸附平衡所用时间最短,对水中COD吸附容量达124.6mg/g,浊度的去除率83%,但对氨氮、pH值无明显吸附效果。 相似文献
353.
辽宁低碳经济的制约因素与应对策略 总被引:1,自引:1,他引:0
气候问题是人类价值所在,低碳经济是全球气候变化背景下中国的必然选择,发展低碳经济,符合国际发展的价值理念和趋势。在全球金融危机背景下,按照低碳经济的发展要求,分析辽宁发展低碳经济面临的主要障碍与制约因素,重点研究适合"低碳经济"要求的辽宁经济结构低碳化调整的应对策略,指出克服技术和资本的锁定效应是辽宁经济结构适应"低碳经济"调整的着力点,最后提出辽宁必须建立发展低碳经济的长效机制。 相似文献
354.
355.
356.
Veronika Dornburg Gregg Marland 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):211-217
Kirschbaum (Mitig Adapt Strat Glob Change 11:1151–1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary
storage of carbon in the terrestrial biosphere “achieves effectively no climate-change mitigation”. His strongly worded statement
begs for a response. This paper argues that Kirschbaum’s conclusion is an artifact of the specific perspective of his analysis
and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change,
a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better
and longer is better, but even known temporary sinks have value.
相似文献
Gregg Marland (Corresponding author)Email: |
357.
G. J. Nabuurs I. J. J. van den Wyngaert W. Daamen H. Kramer P. Kuikman 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):267-282
A full account for carbon dioxide (CO2) and other greenhouse gas balance is presented for the Dutch forest and nature areas for 1990–2002 at a Tier 2.5 level. The
paper outlines how complex guidelines can be turned into a practical system, appropriate for a small country, making use of
the best knowledge and data available. The net total sink of all processes of the forest and other nature terrains balance
is very stable through time around an average of 1.74 million tonnes of CO2 per year. The sink is to a large extent determined by the growth of forest remaining forest, and the harvest taking place
in there. Newly added processes in this new National System are significant as well, but they compensate each other. The sources
from deforestation and nitrous oxide (N2O) emissions (around 900 ktonne CO2) are for two thirds compensated by the sinks from afforestation, dead wood, soil C changes due to land use changes, and trees
outside the forest. The land use changes between 1990 and 2000 showed that The Netherlands has an annual deforestation of
2504 ha (0.7% of the forest area) and an afforestation of 3124 ha. Deforestation led in total over the 13 years of 1990–2002
to an emission of 11.2 million tonne CO2 compensated by only 1.9 million tonne CO2 due to afforestation.
相似文献
G. J. NabuursEmail: |
358.
Natural chemical weathering of silicate rocks is a significant sink for soil and atmospheric CO2. Previous work suggested that natural chemical weathering may be stimulated by applying finely ground silicate rocks to agricultural
areas or forests [stimulated weathering (SW)]. However, it remained unknown if this technique is practical to sequester globally
significant amounts of CO2 under realistic conditions. Applying first estimates of “normal treatment” amounts from a literature review, we report here
a theoretical global maximum potential of 65 106 t sequestered C a−1 if SW would be applied homogenously on all agricultural and forested areas of the world. This is equivalent to 0.9% of anthropogenic
CO2 emissions (reference period 2000–2005). First, however, the assumed application of SW on most of the considered areas is
not economically feasible because of logistic issues, and second the net-CO2 sequestration is expected to amount to only a fraction of consumed CO2 due to the energy demand of the application itself (currently ~11%). Unless progress in application procedures is provided,
the recent realistic maximum net-CO2-consumption potential is expected to be much smaller than 0.1% of anthropogenic emissions, and the SW would thus not be one
of the key techniques to reduce atmospheric CO2 concentration. However, literature suggests that for some agricultural areas (croplands) and specifically for rice production
areas in humid climates, this SW may be a feasible tool to support international efforts to sequester CO2. SW may be cost effective for those areas if linked to the CO2-emission certificate trade in the future, and increases in crop production are taken into account. 相似文献
359.
温室效应和全球变暖已经引起了世界各国的普遍关注,减少二氧化碳等温室气体的排放已成为大势所趋。开发和利用煤层气不仅可避免资源的浪费,还可减少温室气体排放、改善大气环境。本文结合重庆市松藻矿区蝶层气开发利用情况,分析评价了松藻矿区煤层气利用对温室气体减排的贡献。结果表明,煤层气利用具有显著的环境效益和经济效益。 相似文献
360.
M. C. Portillo E. Porca S. Cuezva J. C. Cañaveras S. Sanchez-Moral J. M. Gonzalez 《Die Naturwissenschaften》2009,96(9):1035-1042
Bacteria thriving in underground systems, such as karsts, adapt to use a variety of nutrients. Most of these nutrients derive
from superficial processes. This study shows that bacteria are able to differentially induce carbonate precipitation or dissolution
depending on the availability of nutrients for growth. Different bacterial strains isolated from caves, representing the most
common components of these microbial communities, were cultured with different carbon and nitrogen sources (e.g., acetate,
glucose, peptone, humic acids) and induced changes in pH were measured during growth. Carbonate can either precipitate or
dissolve during bacterial growth. The induction of carbonate precipitates or their dissolution as a function of consumption
of specific carbon sources revealed the existence of an active nutrient cycling process in karsts and links nutrients and
environmental conditions to the existence of a highly significant carbon sink in subterraneous environments. 相似文献