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321.
以铁屑和活性炭构建的原电池研究不同电极间距下高岭土中的镉在原电池电场下的电动力学迁移.随着反应时间的延长,电压和电流均逐渐减小.反应后,高岭土的pH值从阳极到阴极逐渐增加.高岭土中镉含量从阳极向阴极逐渐增加,镉的去除率随电极间距的增加而降低,高岭土的pH值愈低镉的迁移效果愈明显.10cm的电极间距高岭土中镉的去除率达77.9%,在50cm的电极间距下镉的迁移作用很小.表明利用铁炭原电池产生的电场可以驱动污染高岭土中镉的电动力学迁移.  相似文献   
322.
A systematic postal survey of 449 schools in Hong Kong (including kindergartens, primary and secondary schools) was conducted to investigate the use of environmental education teaching kits and to obtain feedback from teachers about the view and comments in using these kits. Results indicated that kindergartens used teaching kits more frequently than secondary and primary schools. Most of the schools found the existing teaching kits helpful. Appropriate content, updated information, attractiveness to students and inclusion of a teachers' guide were considered important criteria in deciding the use of the teaching kits. Good illustrations, quality production and appropriate duration for the class were considered important factors too. The tight teaching schedule was the major hindrance for secondary and primary schools in the use of the environmental teaching kits. However, the main hindrance for using environmental teaching kits in kindergartens was that they did not have sufficient copies. Hong Kong schools would like to see new teaching kits about waste recycling, energy conservation, green behaviour, air pollution, noise pollution, sewage treatment and wildlife endangering, focusing on Hong Kong and China.  相似文献   
323.
The pryene-degradation bacterium strain USTB-X was newly isolated from the polycyclic aromatic hydrocarbon (PAH)-contaminated soil in Beijing Coking Plant, China. The strain was identified as Acinetobacter with respect to its 16S rDNA and morphological and physiological characteristics. The strain was Gram-negative, non-mobile, non-acid-fast, and non-spore-forming, short rods in young culture and 0.8–1.6 μm in diameter and 1.2–2.5 μm long in the stationary phase of growth. Strain USTB-X could utilize pyrene, naphthalene, fluorene, phenanthrene, benzene, toluene, ethylbenzene, ethanol, methanol, and Tween 80 as sole source of carbon and energy. The strain could produce biosurfactants which enhanced the removal of pyrene and could remove 63 % of pyrene with an initial concentration of 100 mg·L?1 in 16 days without other substrates. Based on the intermediates analyzed by gas chromatography-mass spectrometry, we also deduced the possible metabolic pathway of strain USTB-X for pyrene biodegradation. Results indicated that the strain USTB-X had high potential to enhance the removal of PAHs in contaminated sites.  相似文献   
324.
Rice farming sustainability assessment in Bangladesh   总被引:1,自引:0,他引:1  
Farming sustainability is primordial to long-term socioeconomic development. This study assesses rice farming sustainability in Bangladesh by developing a composite indicator (CI) under the four pillars of sustainability and examines the main determining factors. The assemblage of top-down and bottom-up approaches were applied to generate an essential set of indicators and data were collected through a household survey from 15 villages of three major rice growing ecosystems. The results revealed that less than half of the rice growers were sustainable in terms of economical viability, ecological benefits, and quality of life. By category, Boro rice farming was found to be the most sustainable, followed by Aman and Aus rice farming. Human capital development, increasing land productivity, use of resource conserving practices and technologies, and information availability and accessibility were the main factors promoting rice farming sustainability. The findings indicated that the construction of CI by employing several methodologies such as normalisation provide straightforward and clear-cut policy inputs. The major policy implications that emerged from the findings of the study are outlined to actualise rice farming sustainability, which contributes to sustainable development in Bangladesh.  相似文献   
325.
单力 《环境》2006,(9):54-55
电气节能迎来市场空间的断言,源于能源供需的矛盾对我国经济发展的制约。虽然,在此前,从1982年到1998年,机械工业节能产品推广项目和落后机电产品淘汰项目的公布,一直作为一项经常性的工作进行。但在“十一五”节能目标的压力之下,电气节能必将会加快产业节能的步伐。  相似文献   
326.
The term ‘indicator’ is often vague and heterogeneous, and its dynamic characteristics make it highly variable over time and space. Based on reviews and synthesis, this study visualizes phenomena and highlights the trend of indicator selection criteria, development methods, validation evaluation strategies for improvement. In contextualization of the intensification of agriculture and climate change, we proposed a set of indicators for assessing agricultural sustainability in Bangladesh based on theoretically proposed and practically applied indicators by researchers. Also, this article raises several issues of indicator system development and presents a summary after due consideration. Finally, we underline multi-stakeholders’ participation in agricultural sustainability assessment.  相似文献   
327.
Liu J  Li J  Liu Y  Chan HM  Zhao Y  Cai Z  Wu Y 《Environment international》2011,37(7):1206-1212
Perfluorinated compounds (PFCs) are worldwide present in the environment and the general population. Animal studies have shown developmental toxicity of these compounds. To investigate the PFCs exposure of neonates from mother during gestation and lactation, we analyzed twelve PFCs in matched maternal serum, cord serum and breast milk samples collected from 50 pairs of women and their newborns between June and July 2009 in Jinhu, China. Eight PFCs were detected in serum samples, and five of them were also detectable in breast milk. A significant intercorrelation between PFCs concentrations in matched maternal serum, cord serum and breast milk was observed (p<0.01, r=0.435-0.911). The median partition ratio was from 0.39:1 (PFDA) to 1.74:1 (PFTrDA) for seven PFCs through the placenta, and was from 0.02:1 (PFOS) to 0.09:1 (PFOA) for five PFCs through the lactation. A high transport efficiency of PFOA both through placental barrier and lactation was observed. The postnatal exposure of PFCs through lactation was higher compared to prenatal exposure, especially for PFOA.  相似文献   
328.
Biodiesel from waste cooking oil (WCO) and soybean oil (SO) mixture was produced by changing the alkali catalyst (NaOH) content and the WCO to SO ratio in the feedstock. All the prepared biodiesel samples satisfied the standard requirement in terms of free glycerol, density, and acid value. The minimum catalyst content and the highest WCO composition to get biodiesel from the WCO/SO mixture feedstock without ruining the biodiesel properties were 1.0 and 60 wt %, respectively. This conclusion implies that the waste cooking oil mixture, which contains 40 wt % fresh soybean oil, could be treated like the fresh soybean oil to produce biodiesel, and that this behavior would be helpful to reduce the biodiesel production cost when waste cooking oil used as feedstock. The unsaturated methyl esters such as linoleic, and oleic acid were dominant (almost 80 % w/w) in the fresh soybean oil. However the saturated methyl ester was increased due to the double bond breaking during the frying process. These results may deteriorate the biodiesel quality by changing the methyl ester composition.  相似文献   
329.

Background, aim and scope  

This study is the first to investigate PBDE body burden with regard to the concurrent analyses of multiple human matrices, namely milk, placenta, and hair, collected from a group of childbearing-aged women at an electronic waste (e-waste) recycling site to determine the partitioning of PBDEs in these different human matrices and the possible health risks imposed to infants at the e-waste recycling site.  相似文献   
330.
The ecosystem services concept is used to make explicit the diverse benefits ecosystems provide to people, with the goal of improving assessment and, ultimately, decision-making. Alongside material benefits such as natural resources (e.g., clean water, timber), this concept includes—through the ‘cultural’ category of ecosystem services—diverse non-material benefits that people obtain through interactions with ecosystems (e.g., spiritual inspiration, cultural identity, recreation). Despite the longstanding focus of ecosystem services research on measurement, most cultural ecosystem services have defined measurement and inclusion alongside other more ‘material’ services. This gap in measurement of cultural ecosystem services is a product of several perceived problems, some of which are not real problems and some of which can be mitigated or even solved without undue difficulty. Because of the fractured nature of the literature, these problems continue to plague the discussion of cultural services. In this paper we discuss several such problems, which although they have been addressed singly, have not been brought together in a single discussion. There is a need for a single, accessible treatment of the importance and feasibility of integrating cultural ecosystem services alongside others.  相似文献   
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