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841.
842.
Very few data for polybrominated diphenyl ethers (PBDEs) were available in the electronic waste (e-waste) as one of the most PBDEs emission source. This study reported concentrations of PBDEs in e-waste including printer, rice cooker, computer monitor, TV, electric iron and water dispenser, as well as dust from e-waste, e-waste dismantling workshop and surface soil from inside and outside of an e-waste recycling plant in Shanghai, Eastern China. The results showed that PBDEs were detected in the majority of e-waste, and the concentrations of ΣPBDEs ranged from not detected to 175 g/kg, with a mean value of 10.8 g/kg. PBDEs were found in TVs made in China after 1990. The mean concentrations of ΣPBDEs in e-waste made in Korea, Japan, Singapore and China were 1.84 g/kg, 20.5 g/kg, 0.91 g/kg, 4.48 g/kg, respectively. The levels of ΣPBDEs in e-waste made in Japan far exceed the threshold limit of RoHS (1.00 g/kg). BDE-209 dominated in e-waste, accounting for over 93%. The compositional patterns of PBDEs congeners resembled the profile of Saytex 102E, indicating the source of deca-BDE. Among the samples of dust and surface soil from a typical e-waste recycling site, the highest concentrations of Σ18PBDEs and BDE-209 were found in dust in e-waste, ranging from 1960 to 340,710 ng/g and from 910 to 320,400 ng/g, which were 1–2 orders of magnitude higher than other samples. It suggested that PBDEs released from e-waste via dust, and then transferred to surrounding environment.  相似文献   
843.
Extensive research has examined the relationship between environmental management/performance and business performance but yielded no conclusive results. This paper makes two contributions to the literature. First, instead of focusing on one aspect, we try to compare using various types of cleaner production activities: low- and high-cost activities. Second, the study complements the existing literature which focuses on firms in developed countries with an analysis of firms in the Chinese manufacturing industry. In this paper, the relationship between cleaner production and business performance was analyzed using Structure Equation Model (SEM). We find an overall positive impact of cleaner production on firm's business performance. We also found that the cleaner production activities of low-cost scheme have a bigger contribution to financial performance compared to non-financial performance, while cleaner production activities of high-cost scheme have a greater contribution to non-financial performance, compared to financial performance. This study should be useful for firms that consider adopting cleaner production as well as stakeholders who aim to promote cleaner production.  相似文献   
844.
吉林西部退化草地修复方案的仿真优化   总被引:1,自引:0,他引:1  
退化草地的恢复已成为吉林西部农牧业发展的重要任务.为使吉林省西部草地步人可持续发展的良性轨道,如何对退化草地进行恢复就成为研究工作面临的主要问题.首先,运用用RS和GIS技术,建立1989和2004年吉林西部土地利用/土地覆盖空间数据库,研究15年来的吉林西部草地退化情况,草地从1989年至2004年,其总面积减少26.752×104 hm2,15年间减少将近32%.针对吉林西部草地退化状况,提出不同的草地修复规划方案,在系统动力学的指导下,运用VENSIM软件建立了吉林西部草地退化典型区大安市的草地修复规划方案的仿真优化模型,对生产建设型、生态恢复型和生态修复型3种方案进行了仿真优化,其中生态修复型方案,大安市的草地面积以2%的速度恢复,到2020年草地面积为8.23×10.hm2,耕地面积为7.54×104hm2,草地耕地面积比为1.1:1,草地面积占大安市可利用土地面积的41%.农民人均收入达到3 299元,生态效益良好,为吉林西部受损草地生态系统修复的最佳方案.  相似文献   
845.
Nowa days, ecological and cultural tourism, especially those ancient villages and towns in China, have attracted an increasing number of tourists because of their unique cultural features. However, rapid development of tourism brings economic benefits, but results in a series of problems that threaten further tourism development and protection of ancient towns, such as over-commercialization and tourism urbanization. Taking Longmen ancient town as an example, this paper presented a sustainable way of preserving and developing resources of ancient villages and towns. First, identify cultural features and the extent of ancient villages and towns, and find the approach through which a cultural landscape zoning can be applied. Second, define a cooperative function area to release the pressure on core areas and protect their authentic cultures by extending tourism space. Third, balance tourism development with traditional industries to enhance the sustainability of community economies.  相似文献   
846.
The different toxicity characteristics of arsenic species result in discrepant ecological risk.The predicted no-effect concentrations(PNECs) 43.65, 250.18, and 2.00 × 103μg/L were calculated for As(III), As(V), and dimethylarsinic acid in aqueous phase, respectively. With these PNECs, the ecological risk from arsenic species in Pearl River Delta in China and Kwabrafo stream in Ghana was evaluated. It was found that the risk from As(III) and As(V)in the samples from Pearl River Delta was low, while much high in Kwabrafo stream. This study implies that ecological risk of arsenic should be evaluated basing on its species.  相似文献   
847.
非均相催化氧化处理焦化废水   总被引:4,自引:0,他引:4  
研究了非均相催化氧化处理焦化废水的效果。实验得出处理焦化废水的最佳条件:采用经质量浓度为80g/L的硝酸铜溶液浸渍后的γ—Al2O,为催化剂,废水pH为3,催化剂体积分数为40%,H2O2体积分数为4%,反应时间3h以上。原水经处理后COD由4540mg/L降至600mg/L以下,氨氮质量浓度由552mg/L降至160mg/L以下。  相似文献   
848.
PPPUE模式及在中国的应用前景探讨   总被引:3,自引:0,他引:3  
PPPUE是一种全新的应对城市环境问题的模式,这种模式的应用能够充分发挥公共部门、私人部门和第三方的各自优势。本文总结了这种模式的发展过程与基本运作模式,并对PPPUE模式在我国应用的现状、面临的问题以及应用前景作了分析探讨,为解决我国的城市环境问题提供了一种思路。  相似文献   
849.

Metal organic frameworks (MOFs) are excellent adsorbents that provide abundant specific surface area, adjustable pore structure, and rich active sites. The purpose of this study was to prepare composites with hydrophobic and high microporous specific surface area and to adsorb toluene gas in moist ambience. An ethanol activation-assisted hydrothermal method was proposed to synthesize copper-benzene-1,3,5-tricarboxylic acid (Cu-BTC) metal-organic framework, Cu-BTC, and ZSM-5 molecular sieve composites (Cu-BTC@ZSM-5). The dynamic adsorption process of toluene on different adsorbents was investigated, and the results showed that the toluene adsorption capacity of Cu-BTC@ZSM-5 (158.6 mg/g) was 2.53 times higher than Cu-BTC (62.7 mg/g), when the ZSM-5 content is 5% and the humidity is 30%RH. Compared with other factors, the humidity inhibited the adsorption of toluene on Cu-BTC@ZSM-5. Langmuir model and the pseudo-second kinetics model can better describe the adsorption behavior of Cu-BTC@ZSM-5. The thermodynamic results showed the adsorption process was a spontaneous exothermic process at low temperature and mainly physical adsorption. The relative regenerability can still up to 80.4% after six cycles. The adsorption mechanisms of Cu-BTC@ZSM-5 were pore-filling adsorption, π-π interaction, cation-π bonding, and hydrophobic interactions. This study will help to design a systematic route to evaluate the adsorption performance of Cu-BTC@ZSM-5 for toluene.

  相似文献   
850.

The linkage between financial development and energy consumption is widely investigated in the literature. However, the non-linear relationship between financial development and energy demand is still under debate. Therefore, this study aims to examine the non-linear relationship between financial development, economic growth, and energy consumption in OECD countries. The study uses the Driscoll–Kraay standard errors panel regression model for spanning from 1980 to 2016. The empirical findings indicate that an inverted U-shape relationship exists between financial development and energy consumption as well as between economic growth and energy consumption. Moreover, the feedback hypothesis is found between financial development and energy use. Additionally, income and energy use granger cause each other. The innovative findings contribute to extant literature, which is of special interest to the country’s policymakers regarding energy efficiency.

  相似文献   
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