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931.
With the increasing number of recycling mishaps in connection with waste electronic and electrical equipment (WEEE) in the People's Republic of China, it is imperative that the handling and recycling of WEEE be sufficiently regulated in China. Regulations covering three major issues, namely, take-back issues, controls on hazardous substances in WEEE and the assurance of good environmental management in WEEE plants, were promulgated between 2006 and 2008. The evaluation in this country report shows that few of these regulatory measures have performed satisfactorily in terms of enforcement, of public acceptance and of environmental concerns. In brief, the take-back requirements and the associated financial responsibilities are only vaguely defined; the control on hazardous substances and the so-called "environmental expiry date" requirements cannot be properly enforced, and the resources needed to ensure the satisfactory enforcement of the environmental abatement and pollution control requirements in WEEE plants are overwhelming. In addition, the use of a "multiple enforcement body" approach to the control of hazardous substances in WEEE is an indication that the Chinese government lacks the determination to properly enforce the relevant legal requirements. 相似文献
932.
Environmental assessment of garden waste management in the Municipality of Aarhus, Denmark 总被引:1,自引:0,他引:1
An environmental assessment of six scenarios for handling of garden waste in the Municipality of Aarhus (Denmark) was performed from a life cycle perspective by means of the LCA-model EASEWASTE. In the first (baseline) scenario, the current garden waste management system based on windrow composting was assessed, while in the other five scenarios alternative solutions including incineration and home composting of fractions of the garden waste were evaluated. The environmental profile (normalised to Person Equivalent, PE) of the current garden waste management in Aarhus is in the order of −6 to 8 mPE Mg−1 ww for the non-toxic categories and up to 100 mPE Mg−1 ww for the toxic categories. The potential impacts on non-toxic categories are much smaller than what is found for other fractions of municipal solid waste. Incineration (up to 35% of the garden waste) and home composting (up to 18% of the garden waste) seem from an environmental point of view suitable for diverting waste away from the composting facility in order to increase its capacity. In particular the incineration of woody parts of the garden waste improved the environmental profile of the garden waste management significantly. 相似文献
933.
Ting Gui Gui F. Jia Jin Xu Shi J. Ge Xiao F. Long 《Journal of environmental science and health. Part. B》2019,54(4):326-335
A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed for the determination of thiamethoxam and its metabolite clothianidin in citrus (including the whole citrus, peel and pulp) and soil samples by liquid chromatography-tandem mass spectrometry. The sample was extracted with acetonitrile and purified with octadecylsilane. The detection limits of both compounds were 0.0001–0.0002?mg kg–1, while the limit of quantification of thiamethoxam was 0.002?mg kg–1 and the limit of quantitation of metabolites was 0.001?mg kg–1. The recovery was 70.37%–109.76%, with inter-day relative standard deviations (RSD) (n?=?15) values ≤9.46% for the two compounds in the four matrices. The degradation curve of thiamethoxam in whole citrus and soil was plotted using the first-order kinetic model. The half-life of the whole citrus was 1.9–6.2?days, and the half-life of the soil was 3.9–4.2?days. The terminal residue of thiamethoxam (the sum of thiamethoxam and clothianidin, expressed as thiamethoxam) was found to be concentrated on the peel. The final residual amount of thiamethoxam in the edible portion (pulp) was less than 0.061?mg kg–1. The risk quotient values were all below 1, indicating that thiamethoxam as a citrus insecticide does not pose a health risk to humans at the recommended dosage. 相似文献
934.
Yurong Yu Shouyi Wang Qingtao Zhang Ya Yang Ya Chen Xiangwu Liu 《Journal of environmental science and health. Part. B》2019,54(2):89-97
A shortened version of Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) for determining the dissipation and residue of imidacloprid present in Zizania latifolia and purple sweet potato was established by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average recoveries of imidacloprid in the two crops ranged from 82.12 to 113.79%, with relative standard deviation (RSD) of <7.32%. The dissipation dynamics of imidacloprid in Z. latifolia plants and purple sweet potato plants followed first-order kinetics, with half-lives of 3.2–5.5?days in each of sampling locations. The terminal imidacloprid residues in Z. latifolia and purple sweet potato at each of location were <0.005–0.120?mg kg?1. According to the risk assessment results, both the acute dietary risk quotient and chronic dietary risk quotient values were <1, indicating that imidacloprid is unlikely to pose health risks to humans with normal recommended use. The present study may serve as a valuable reference for the safe and reasonable use of imidacloprid in Z. latifolia and purple sweet potato fields. 相似文献
935.
Karimoun M. Illyassou Rabani Adamou Bruno Schiffers 《Journal of environmental science and health. Part. B》2019,54(3):176-186
The use of pesticides in horticultural sector in Niger has become an integral part of modern agriculture. Nevertheless, their inappropriate use can generate negative health effects to operators. A study was carried out among Kongou farmers in order to assess their potential dermal exposure (PDE). The UK-POEM model was used to quantify the PDE during mixing/loading and application according to the local practices. In order to determine which parts of the operator body are subject to most contamination during spraying and to validate the theoretical model used, a patch method was used with a tartrazine dye. The deposits of the tartrazine on patches were measured by colorimetry thanks to the absorbance value determined after their extraction in water and a calibration curve. A total of ten spraying trials (five trials with the hand-held sprayer and five others with the backpack sprayer) were performed by different producers at 0.5 and 1 m height for each trial. The survey shows that 92% of the farmers are illiterate and the most common active substances identified are organophosphate or pyrethroids insecticides. Seventy percent of operators do not use any personal protective equipment (PPE) during mixing/loading or spraying. The predictive systemic exposure levels vary from 0.0027?mg kg?1 bw per day to 0.7692?mg kg?1 bw per day for backpack sprayer and from 0.0261?mg kg?1 bw per day to 0.9788?mg kg?1 bw per day for hand-held sprayer, several times higher the Acceptable Operator Exposure Level (AOEL) for some actives substances. Theoretical modeling indicates more exposure of operator by a hand-held sprayer than a backpack sprayer. The patch method results show that the deposits of dye increase when the position of sprayer nozzle increases from 0.5 to 1 m for the two sprayers. All parts of the operator body are contaminated but lower body parts and chest are the most exposed. The patch method results also show that hand spraying contaminates operator more than backpack spraying, confirming the results of the theoretical model. 相似文献
936.
黄河中上游能源化工区大气污染跨界环境影响分析 总被引:1,自引:0,他引:1
对黄河中上游能源化工区近地面和边界层顶气象流场及该区域大气污染长距离输送产生的跨界环境影响趋势特征进行了分析。结果表明,该区域近地面和边界层顶的流场总体上为西北向东南流动,大气污染物长距离输送可能影响的区域主要为华中地区;区域冷空气的活动对其大气污染物的清除起重要作用;通过CALPUFF模型的模拟结果表明,该区域SO2的影响程度和范围明显大于NO2,在区域内部存在污染物浓度较高的区域,但未对区外造成显著跨界环境影响。 相似文献
937.
中国工程院国际工程科技高端论坛暨PACE 20周年纪念大会于2017年8月28~29日在北京举行。PACE 20周年大会就"水资源水环境政策"和"环境社会治理"两个主题进行了深入研讨,并达成以下共识:政府治理是中国水资源水环境治理的主导模式,但目前我国水资源水环境政府治理仍面临政策不规范、立法不完善、监管不到位等实质性的问题,要积极促进政策的制定与执行;环境社会治理是我国环境治理的短板,环境治理不仅需要政府的主导,更需要社会上的利益相关方参与政策制定、监督与执行过程,更需要社会各行为主体的自觉自主行动,促进环境行为改善,化解由环境引起的社会矛盾。 相似文献
938.
939.
Yajun Lv Weizhun Jin Yan Yang Xinzhong Zhang Fangyi Ding 《International Journal of Green Energy》2017,14(11):916-924
This paper aims to reveal the heat transfer mechanism of low-temperature phase change material (PCM) and design PCM heat storage device in building heating environment. Firstly, low-temperature binary PCMs of lauric acid and stearic acid are prepared, and their thermal properties are investigated by DSC. Then, shell and tube latent heat thermal energy storage units are conducted, and heat transfer experiments are carried out to analyze the heat transfer mechanism of PCM. The results demonstrate that natural convection plays an important role in heat transfer process, and the heat storage efficiency of PCMs can be significantly enhanced by increasing the fin width and improving the inlet heat transfer fluid (HTF) temperature. Furthermore, some proposals are put forward to guide the design of PCM storage device in building heating environment. 相似文献
940.
Pressure-retarded osmosis (PRO) is a method for converting salinity gradients to power by allowing water to flow through a semi-permeable membrane against an applied hydraulic pressure. PRO already has a long history, starting from the middle of the last century, and has rapidly improved in recent years. In this paper, we present a historical development of PRO since its inception: the development of this renewable energy process has gone through several stages, depending on technological developments, worldwide energy demands, and environmental concerns. The technological progress of the process is also studied, as well as its cost viability and environmental impact. Finally, some ideas to further develop the PRO process and mitigate its detrimental effects are discussed. 相似文献