首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   113篇
  免费   0篇
  国内免费   15篇
安全科学   1篇
废物处理   40篇
环保管理   2篇
综合类   26篇
基础理论   10篇
污染及防治   40篇
评价与监测   2篇
社会与环境   6篇
灾害及防治   1篇
  2021年   2篇
  2019年   1篇
  2018年   6篇
  2017年   6篇
  2016年   5篇
  2015年   3篇
  2014年   4篇
  2013年   14篇
  2012年   12篇
  2011年   9篇
  2010年   3篇
  2009年   11篇
  2008年   6篇
  2007年   18篇
  2006年   5篇
  2005年   2篇
  2004年   7篇
  2003年   3篇
  2002年   4篇
  2001年   3篇
  2000年   1篇
  1990年   1篇
  1985年   1篇
  1970年   1篇
排序方式: 共有128条查询结果,搜索用时 953 毫秒
61.
62.
Theoretical and empirical studies have been conducted on the genuine saving (GS) based on neoclassical economic theory to assess sustainable development (SD). However, only market prices and statistical national accounts have been used in empirical studies due to limited data availability. The data availability limits to measure GS only in the past and current, causing a wide gap with theoretical results. In this paper, we propose computing GS using an integrated assessment model (IAM) as connected to the mainframe model of macroeconomy. This enables us to use shadow prices, rather than market prices, obtained through an IAM, which ensures substantial consistency among variables. An example would be endogenous capital–output ratio and the rate of TFP. Also, our indicator of GS is more comprehensive in that they now account for various resources, environmental degradation, and land use. Our simulation results, with a particular focus on GS with population change (GSn) and with technological change as well (GSnt), show a sustainable future for up to the end of the century thanks to declining population in the latter half of the century and technological progress, although GS without accounting for population and technology tend to be negative, driven by, among others, capital depreciation and net primary productivity degraded by land use.  相似文献   
63.
Journal of Material Cycles and Waste Management - Anaerobic digestion (AD) is a sustainable technology that combines biogas production with proper waste management. However, the operation of an...  相似文献   
64.
Maezono T  Tokumura M  Sekine M  Kawase Y 《Chemosphere》2011,82(10):1422-1430
Dynamic behaviors of hydroxyl (OH) radical generation and consumption in photo-Fenton oxidation process were investigated by measuring OH radical concentration during the discoloration of azo-dye Orange II. The effects of operating parameters for photo-Fenton discoloration, i.e. dosages of H2O2 and Fe, initial dye concentration, solution pH and UV irradiation, on the generation and consumption of OH radicals playing the main role in advanced oxidation processes were extensively studied. The scavenger probe or trapping technique in which coumarin is scavenger of OH radical was applied to estimate OH radical concentration in the photoreactor during the photo-Fenton discoloration process. The OH radical generation was enhanced with increasing the dosages of Fenton regents, H2O2 and Fe. At the initial stage of photo-Fenton discoloration of Orange II, the OH radical concentration rapidly increased (Phase-I) and the OH radical concentration decreased after reaching of OH radical concentration at maximum value (Phase-II). The decrease in OH radical concentration started when the complete discoloration of Orange II was nearly achieved and the H2O2 concentration became rather low. The dynamic behavior of OH radical concentration during the discoloration of Orange II was found to be strongly linked with the change in H2O2 concentration. The generation of OH radical was maximum at solution pH of 3.0 and decreased with an increase of solution pH. The OH radical generation rate in the Fenton Process was rather slower than that in the photo-Fenton process.  相似文献   
65.
Kim YJ  Osako M  Sakai S 《Chemosphere》2006,65(3):506-513
To investigate the effect of leachant on the leachability of polybrominated diphenyl ethers (PBDEs), we determined the leaching concentrations of PBDEs from flame-retardant plastic samples (TV housings and raw materials before molding processing) that are regarded as a source of PBDEs in landfill sites. The leachants used were distilled water, 20% methanol solution, and dissolved humic solution (DHS) of 1000 mg/l based on organic carbon. The leaching test conditions were a liquid-to-solid ratio of 100:1, and a contact period of five days, with twice-daily agitation in a temperature-controlled room of 30 degrees C without pH or ionic strength control. The leaching concentrations of PBDEs increased with increased content, and were found to be remarkably enhanced when methanol and DHS were used instead of distilled water. The enhancement of leachability in the presence of the latter was attributed to the cosolvency effect, and complex formations between the PBDEs and dissolved humic matter (DHM). PBDE concentrations in the leachate obtained from the leaching test and an actual landfill site revealed a significant presence of congeners below heptabromodiphenyl ethers (H7BDEs), detected in the leachate of the actual landfill, while significant amounts of nonabromodiphenyl ethers (N9BDEs) and decabromodiphenyl ether (D10BDE) were detected in the leachate of the leaching test.  相似文献   
66.
To elucidate the ecological impacts of imidacloprid [1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] on vegetable crops and their surrounding areas, arthropods on eggplant patches treated with this insecticide were monitored throughout two cultivation seasons, spring and autumn, and the results compared with those of control crops. Residues of imidacloprid in soil accounted for 4-8% of total applied, and concentrations outside the crop were always below 5 micro g/kg. Communities of the crop vegetation experienced significant density reductions, mostly of aphids, and had fewer species diversity during the first month. Those in the surrounding pasture were similarly affected though with less intensity, while non-target ground arthropods both inside and outside the crop only showed significant impacts in the two weeks after planting.  相似文献   
67.
To clarify the mechanism of hypoxia in the western interior parts of the Ariake Sea (WIAS), field observation data collected in the period of 1972-2004 were analyzed using a two-layer box model. Monthly averages of advection velocity, vertical diffusion coefficient (K(z)), and biochemical oxygen consumption rate (R) in WIAS were evaluated quantitatively during the above period. The estimated advection velocity comparatively corresponded to the observed residual flow pattern of bay head in summer and winter. The estimated K(z) was relatively high (0.6-5.3 cm(2) s(?-1)) from September to March but lower (0.2-0.4 cm(2) s(?-1)) from April to August. The estimated R ranged from 0.30 to 0.46 mg L(?-1) day(?-1) during May to August. In summer, the temporal variation of dissolved oxygen (DO) concentration in the lower layer was controlled largely by K ( z ) and R. Monthly variations of K(z), R, and degree of density stratification (P) in the 1970s, the 1980s, and the 1990s-early 2000s were analyzed. P, K ( z ), and R were not significantly different among the calculated periods (p = 0.93, 0.23, and 0.49). However, the variations of R in summer between the 1970s and the other calculated periods changed. DO consumption period was longer in the 1980s and the 1990s-early 2000s than in the 1970s. R in the 1980s was highest among the calculated periods. The increase in R in the 1980s was caused by the increase in organic matter load originating from red tide phytoplankton due to a decrease in the suspension feeders.  相似文献   
68.
To enhance the production of lipopeptide antibiotic iturin A, nutrient contents of the culture mediums were investigated in both submerged and biofilm fermentations. As a carbon source maltose and as nitrogen source, fish protein was used. In submerged fermentation maltose uptake was found lower (12%) compared to biofilm fermentation (15%) that was associated with higher cellular growth in biofilm. However, requirement of nitrogen (fish protein) concentration was found similar in both submerged and biofilm fermentations. Production of iturin A in submerged fermentation with 12% maltose and 5% fish protein was 4450 mg/L, and in biofilm fermentation it was 5050 mg/L when 15% maltose and 5% fish protein was used.  相似文献   
69.
An inhibitory effect of a traditional Japanese fermented food, natto, was found against plant pathogens such as Rhizoctonia solani and Fusarium oxysporum, and the bacteria which showed inhibition were isolated from the natto. Among isolated bacteria, BC-1 and GAc exhibited a strong antagonistic effect in vitro against plant pathogens on an agar medium. The supernatant of bacterial culture also showed strong activity against R. solani, which meant the antimicrobial substances were produced and secreted into the medium. Both of the bacteria were estimated as Bacillus amyloliquefaciens from a partial sequence of the 16s rRNA gene. High performance liquid chromatography analysis clearly showed the production of the lipopeptide antibiotic iturin A by BC-1 and GAc.  相似文献   
70.
Bacterial endophytes were found from 6 plant leaves among 35 plant leaves screened. Two of the isolated bacteria showed antagonistic activity against fungal plant pathogens. An isolate named KL1 showed the clear inihibition against plant pathogens, Fusarium oxysporum and Rhizoctonia solani, on PDA as well as TSA plate. Supernatant of the bacterial culture also showed the clear inhibition against the fungal growth on the plate and the antibiotic substance was identified as iturin A by HPLC analysis. KL1 was identified as Bacillus sp. from the 16S rRNA gene analysis. Very thin hyphae of R. solani was miccroscopically observed when the fungus was co-cultivated with KL1.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号