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212.
Jingjing Deng Jie Guo Xiaoyu Zhou Peng Zhou Xiaoxu Fu Wei Zhang Kuangfei Lin 《Environmental science and pollution research international》2014,21(12):7656-7667
Various hazardous substances contained in waste TV sets might be released into environment via dust during recycling activities. Two brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), and tetrabromobisphenol A (TBBPA), and five kinds of heavy metals (Cu, Pb, Cd, Cr, and Ni) were detected in indoor dust collected from two workshops (TV dismantling workshop and subsequent recycling workshop). PBDEs concentrations in dust from waste wires recycling line (722,000 ng/g) were the highest among the studied sites, followed by those in manual dismantling–sorting line (117,000 ng/g), whereas TBBPA concentrations were the highest in manual dismantling–sorting line (557 ng/g) and printed circuit board (PCB) recycling line (428 ng/g). For heavy metals, Cu and Pb were the most enriched metals in all dust samples. The highest concentration of Pb (22,900 mg/kg) was found in TV dismantling workshop-floor dust. Meanwhile, Cu was the predominant metal in dust from the PCB recycling line, especially in dust collected from electrostatic separation area (42,700 mg/kg). Occupational exposure assessment results showed that workers were the most exposed to BDE-209 among the four PBDE congeners (BDE-47, BDE-99, BDE-153, and BDE-209) in both workshops. The hazard quotient (HQ) indicated that noncancerous effects were unlikely for both BFRs and heavy metals (HQ?<?1), and carcinogenic risks for Cd, Cr, and Ni (risk?<?10?6) on workers in two workshops were relatively low. 相似文献
213.
MCM-41介孔分子筛的合成及其对铜离子的吸附性能简 总被引:1,自引:0,他引:1
以微硅粉为硅源,CTAB和PEG-6000为模板剂,合成MCM-41介孔分子筛。采用XRD、N2吸附-脱附曲线、FTIR以及TEM表征了其结构、比表面积、孔径分布及晶体形貌,并且以该样品为吸附剂,对含Cu2+的溶液进行了静态吸附实验。结果表明,以微硅粉为硅源成功合成了具有典型六方排列孔道结构的MCM-41,其比表面积为869.5 m2/g,孔容为0.97 cm3/g,平均孔径为3.3 nm;溶液pH为5~6时,MCM-41对Cu2+的去除效果最好;MCM-41对Cu2+的最大吸附吸附容量36.3 mg/g;MCM-41对Cu2+的吸附性能符合Langmuir吸附方程的特征。动力学研究表明,该过程符合准二级动力学模型。 相似文献
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原铝生产流程温室气体排放主要影响因素的关联度分析 总被引:1,自引:0,他引:1
铝是国民经济建设和发展的关键基础材料,然而由其生产过程所产生的大量温室气体排放也逐渐成为政府关注的焦点。本研究计算了我国原铝生产不同年度的生命周期能耗和温室气体排放量,并分析了资源消耗和生产工序能耗等影响因素与温室气体排放的关联性。结果表明,在各年原铝生产的温室气体排放总量中,电力和阳极效应导致的排放所占比重分别为68.5%和7.9%,其他影响因素所占比重均低于6%;与温室气体排放关联度最高的3个影响因素依次是电耗、煤气燃烧和石灰石煅烧,其值分别为0.937、0.899和0.893;在目前铝电耗和阳极效应控制水平提升空间有限的情况下,降低煤气的消耗,提高石灰石的使用效率,是实现原铝生产温室气体减排的有效途径。 相似文献
217.
基于土地利用变化的四川省生态系统服务价值研究 总被引:11,自引:0,他引:11
认识和理解土地利用变化对生态系统服务价值的影响及相互作用关系具有重要意义。在分析国内外各种生态服务价值评价方法和对各类生态系统生态服务价值系数进行修正的基础上,采用生态系统服务价值评估模型、敏感性指数和价值变率模型,对各类生态系统的各项生态服务价值、土地利用变化对四川省生态系统服务价值的影响进行了计算和分析。结果表明:(1)四川省土地利用以林地和牧草地为主,1996~2006年耕地、未利用土地、牧草地和水域面积减少,林地、建设用地和园地面积呈增加趋势;(2)1996~2006年四川省生态系统服务价值由1996年的7 214588×108元上升到2006年的7 305018×108元,增加90431×108元,园地生态系统服务价值持续增加,而农田、牧草地、水域、未利用地则继续减少;(3)土地利用的生态服务价值区域差异显著,空间上呈现西多东少的分布格局,西部高山高原区和盆周山区的生态系统服务价值总量较大,成都平原和四川盆地丘陵区所提供的较少;(4)四川省生态系统服务价值缺乏弹性,价值变率反映林地面积的变化对研究区生态系统服务价值的变化具有较大影响 相似文献
218.
Yanyan Fang Zhiqiang Nie Feng Liu Qingqi Die Jie He Qifei Huang 《Environmental science and pollution research international》2014,21(19):11401-11408
Concentrations of heavy metals (As, Cd, Pb, Cu, Ni, Fe, Mn, and Zn) in market vegetables and fishes in Beijing, China, are investigated, and their health risk to local consumers is evaluated by calculating the target hazard quotient (THQ). The heavy metal concentrations in vegetables and fishes ranged from not detectable (ND) to 0.21 mg/kg fresh weight (f.w.) (As), ND to 0.10 mg/kg f.w. (Cd), and n.d to 0.57 mg/kg f.w. (Pb), with average concentrations of 0.17, 0.04, and 0.24 mg/kg f.w., respectively. The measured concentrations of As, Cd, Pb, Cu, Ni, Fe, Mn, and Zn are generally lower than the safety limits given by the Chinese regulation safety and quality standards of agriculture products (GB2762-2012). As, Cd, and Pb contaminations are found in vegetables and fishes. The exceeding standard rates are 19 % for As, 3 % for Cd, and 25 % for Pb. Pb contaminations are found quite focused on the fish samples from traditional agri-product markets. The paper further analyzed the health risk of heavy metals in vegetables and fishes respectively from supermarkets and traditional agri-product markets; the results showed that the fishes of traditional agri-product markets have higher health risk, while the supermarkets have vegetables of higher heavy metal risk, and the supervision should be strengthened in the fish supply channels in traditional agri-product markets. 相似文献
219.
利用白云石石灰去除与回收污泥厌氧消化液中氮和磷 总被引:1,自引:0,他引:1
以白云石石灰为实验材料去除与回收污泥厌氧消化液中的氮磷,通过小试实验研究不同投药固液比S/L、初始pH值、反应温度、搅拌速度及反应时间对去除与回收氮磷效果的影响。实验结果表明,在最佳投药固液比S/L为300mg/L,最佳初始pH值范围为8.5~9.5,反应温度为25.0℃,搅拌速度为150 r/min,反应时间为24 h条件下,氨氮(NH+4-N)和磷(PO3-4-P)的去除率分别为37.26%和89.60%。利用X射线衍射仪(XRD)、扫描电镜(SEM)对沉淀产物进行了表征,通过分析可知沉淀产物中含有磷酸铵镁(MAP),可实现废水中氮磷经济有效的回收。 相似文献
220.
Some technical issues in managing PCBs 总被引:1,自引:0,他引:1
Zhifu Qi Alfons Buekens Jie Liu Tong Chen Shengyong Lu Xiaodong Li Kefa Cen 《Environmental science and pollution research international》2014,21(10):6448-6462
Polychlorinated biphenyls (PCBs) were important industrial chemicals featuring high thermal and chemical stability and low flammability. They were widely used as dielectric and thermal fluid in closed electro-technical applications (transformers, capacitors…) and also in numerous dispersive uses, ranking from auto-copying paper to sealant or coatings. During the 1960s, severe environmental consequences started becoming apparent. The stability of PCBs contributed to their persistence in the environment, their lipophilic character to bio-magnification. Fish-eating species seemed threatened in their existence. In Japan and in Taiwan, thousands of people consumed PCB-contaminated oil. The production of PCBs stopped completely during the 1980s. Usage could continue in closed applications only. In this paper, particular attention is given to two issues: the cleaning of PCB electric transformers and the potential impact of PCB-containing building materials. Other contributions will cover the management and treatment of PCB-contaminated soil, sludge or fly ash. The complete survey is being prepared by request of the Knowledge Center for Engineers and Professionals. 相似文献