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162.
运用生命周期分析技术可从全过程的视角识别和比较不同城市污水处理工艺在其生命周期各个阶段的能耗 ,并在此基础上提出改善其能效的措施。本文运用LCA方法对厌氧水解 -活性污泥法处理系统从其原材料开采和加工开始直至污水厂施工建设、处理运行以及废弃拆除的LC全过程能耗进行了识别和量化分析 ,并与普通活性污泥法进行了平行对照。研究结果表明 ,在微孔和穿孔管两种曝气条件下与普通活性污泥法相比 ,厌氧水解法的LC能耗分别节省 14.0 %和 17.6%。由于污泥产量较低 ,厌氧水解法的比能耗大幅度提高 67.7%~ 77.7%。 相似文献
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164.
Isaak Zonneveld 《环境科学学报(英文版)》2003,15(2):152-154
This study includes ome aspects of the shift in the Dutch attitude in relation to water during the past millennia from defense to attack to keeping the balance(“co-evolution“).It has a special focus on the freshwater tidal part,which embraces the largest of the world:Rotterdam ,as well as the largest national park of the Northerlands.It reports especially about a young mans endeavor in half a c century real time monitoring of some land (scape) units with simple means. 相似文献
165.
Katharina Rietig 《环境政策》2019,28(2):228-247
ABSTRACTEuropean climate policy faced increasing constraints during the economic and Eurozone crises (2008–2014). The European Commission subsequently refocused policymaking toward integrating climate objectives into other policy areas such as energy and the 2014–2020 European Union (EU) budget. The conditions for successful climate policy integration (CPI) are analyzed, focusing on the compatibility of key actors’ beliefs. In renewable energy policy, CPI was successful as long as the co-benefits and related policy-core beliefs of energy security, rural economic development and climate action coexisted harmoniously. Once conflict among these policy-core beliefs emerged during the biofuels controversy, CPI was weakened as actors with competing economy-focused beliefs controlled the decision-making process. The case of EU budget climate mainstreaming illustrates how actors can add climate objectives into legislation despite meaningful discussion being ‘crowded out’ by other priorities. The findings highlight the importance of low conflict between departments, compatible beliefs and policy priorities for successful CPI. 相似文献
166.
Kurt B. Carlsson 《Chemosphere》1989,18(9-10):1731-1736
The graph below shows the emitted dioxin - equivalents (Eadon) in grams per year in flue gas from municipal solid waste incinerators with various air pollution control methods for plants of capacity of 200 000 ton municipal solid waste (MSW) per year.
Full-size image (15K)
With optimized combustion and an effective air pollution control system the emissions of dioxins can be kept very low (concentrations below 0.1 ng/m3n).
With a very effective air pollution control system the total emission from all Swedish MSW-incinerators burning approximately 1.5 Mton/year will by 1990 be below 2 g/year - a drastic reduction from approximately 15 g today. As the total dioxin - equivalent emission to the environment in Sweden in the year 1987 was almost 500 g we see that municipal waste incineration really is on the way to solve their dioxin problem. 相似文献
167.
Amanda H. Korstjens Ingrid Lugo Verhoeckx Robin I. M. Dunbar 《Behavioral ecology and sociobiology》2006,60(5):683-694
An animal can only survive in a given habitat if it has enough time to find, process and digest food whilst avoiding predation. The time it has for food acquisition is affected by the vegetation and competition with conspecifics, which depends on aggregation tendencies. We used the relationships between time allocations, on the one hand, and climatic variables (as a proxy for habitat quality) and group size, on the other, to develop a model that predicts maximum ecologically tolerable group size at different locations for spider monkeys. Spider monkeys are particularly interesting because the social communities often split up into small units. Temperature variation and rainfall variation were the main determinants of time budgets. Community size and average annual rainfall determined party size. The model correctly predicted presence or absence of spider monkeys at 78–83% of 217 New World forest sites. Within the geographical range of the species, this time budget model predicted the presence of spider monkeys better than a model based directly on climate variables. Predicted community and party sizes were significantly larger at sites where spider monkeys are present than at sites where they are absent. As required by the model, predicted maximum community sizes were significantly larger than observed community sizes. Moving time showed a U-shaped relationship with party size, which suggests that moving time is the factor that keeps spider monkey communities from travelling together in a tight group. 相似文献
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169.
Fanie?PelletierEmail author Marco?Festa-Bianchet 《Behavioral ecology and sociobiology》2004,56(6):546-551
In sexually dimorphic ungulates, males generally spend less time foraging than females, possibly because of difference in body mass or because of the energetic requirements of lactation. The relationship between body size and foraging time has received little attention at the intra-specific level, because few studies have documented activity budgets for individuals of known size. Bighorn rams are a good model to explore how body mass affects foraging time, because they range in mass from 55 to 140 kg. We examined how the foraging time of bighorn rams varied according to individual characteristics. We observed rams in a marked population and constructed time budgets during the 3 months preceding the rut. We determined ram social rank based on agonistic encounters and collected fecal samples to count lungworm larvae. Time spent foraging was negatively correlated with body mass. After accounting for age differences, larger rams spent less time foraging and more time lying than smaller rams. Among rams aged 6–12 years, dominants spent less time feeding than subordinates, while fecal output of lungworm larvae was negatively correlated with foraging time for rams of all ages. Body mass accounts for much of the individual variation in foraging time, suggesting that sexual dimorphism is important in explaining differences in feeding time between males and females.Communicated by P. Heeb 相似文献
170.
中国能源消费与温室气体排放预测分析 总被引:4,自引:0,他引:4
构造了中国18个部门的能源—经济—环境投入产出模型,分析了能源消耗系数的变动规律,对2020年我国能源消费量与温室气体排放量进行了预测。结果表明:我国2020年的能源消费总量为29.5亿t(标准煤),等于1990年的299%,1995年的229%;煤炭消费最为26亿t,石油消费量为4.1亿t,天然气消费量为1420亿m~3,水电6400亿kW·h;能源消费弹性系数为0.43左右;CO_2排放量为17.50亿t(碳当量)。 相似文献