Bioavailability and tissue distribution of Dechloranes in wild frogs (Rana limnocharis) from an e-waste recycling area in Southeast China

Dechlorane Plus(DP), a flame retardant used as an alternative to decabromodiphenylether, has been frequently detected in organisms, indicating its bioaccumulation and biomagnification potential in aquatic and terrestrial species. However, little data is available on the bioaccumulation of DP in amphibians. Dechlorane Plus and its analogs(DPs) were detected in the liver, muscle and brain tissues of wild frogs(Rana limnocharis), which were collected from an e-waste recycling site, Southeast China. DP, Mirex, Dec 602 and a dechlorinated compound of DP(anti-Cl11-DP) varied in the range of 2.01–291, 0.650–179, 0.260–12.4, and not detected(nd)–8.67 ng/g lipid weight, respectively. No difference of tissue distribution was found for syn-DP, Mirex and Dec 602 between the liver and muscle tissue(liver/muscle concentration ratio close to 1, p 0.05). However, higher retention was observed for anti-DP and anti-Cl11-DP in the frog muscle relative to the liver tissue(liver/muscle concentration ratio 1, p 0.05). Additionally, the blood-brain barrier was found to work efficiently to suppress these compounds entering brain tissues in this species(liver/brain concentration ratio 1, p 0.05), and the molecular weight was a key factor impacting the extent of the blood-brain barrier. Compared to levels in the muscle and brain tissue, a preferential enrichment of syn-DP was observed in the liver tissue, suggesting the occurrence of stereo-selective bioaccumulation in the wild frog.     

Photodegradation of 2,4-D induced by NO2- in aqueous solutions：The role of NO2

To elucidate the effect of nitrite ion （NO2^-） on the photodegradation of organic pollutants, a 300 W mercury lamp and Pyrex tubes restricting the transmission of wavelengths below 290nm were used to simulate sunlight, and the photodegradation processes of 2,4-dichlorophenoxyacetic acid （2,4-D） with different concentrations of NO2^- in freshwater and seawater were studied. The effect of reactive oxygen species （ROS） on the photolysis of 2,4-D was also demonstrated using electron paramagnetic resonance （EPR）. The results indicated that the 2,4-D photolysis reaction followed the first-order kinetics in freshwater and seawater under different concentrations of NO2^-. Meanwhile, the photochemical reaction rate of 2,4-D increased with increasing concentration of NO2^-. When the concentration of NO2^- was lower than 23 mg/L, the photodegradation rate of 2,4-D in seawater was higher than that in freshwater. However, when the concentration of NO2^- was reached 230 mg/L, 2,4-D degradation slowed down in seawater. It was important to note that EPR spectra showed NO2 radical was generated in the NO5 solution under simulated sunlight irradiation, indicating that 2,4-D photodegradation could be induced by NO2. These results show the key role of NO2^- in photochemistry and are helpful for better understanding of the phototransformation of environmental contaminants in natural aquatic systems.     

电子垃圾:不需开矿的金属——选自《蓝色经济》经典案例

<正>市场美国消费者每天抛弃的电脑超过11万台。每年电子垃圾数量已增加至45000万台。美国在过去十年报废的电子设备大约为30亿台。电子垃圾是城市固体垃圾中增长最快的类别,不幸的是,这些废物的回收平均不到10%。最终进填埋场或焚烧炉。2012年,全球电脑销售量达到     

垃圾零填埋

<正>随着人类的发展,作为人类专属产物的垃圾也伴随着人类文明,不断地挑战着我们的生存环境,污浊着我们的家园。时至今日,人类早已警觉到了垃圾处理的必要和迫切。垃圾的分类投放、回收再利用、运用垃圾发电等等,人类正在想着法子将垃圾变废为宝,但是,至今还无法从根本上改变垃圾     

碳捕获与储存生活测试

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浅谈安防集成管理平台在智慧城市建设中的应用与发展

智慧城市的建设在国内外许多地区已经展开,并取得了一系列成果。在智慧城市建设的号召下,安防正在更多地融入智慧城市,并且服务于智慧城市。当前,安防技术正在从经典向现代转变,其中共性的技术——特别是视频技术,正在进入公共安全领域,服务智慧城市。信息技术发展的趋势,促使安防技术为智能城市提供技术支撑,借助技术融合的核心、服务性、开放性成为社会管理平台的一部分,成为智能建筑、智慧城市的重要(功能)组成。智慧城市的发展也将成为助推安防行业发展的新旗帜。     

宁波瑞奥(Rayosys)

安全、便捷、智能,轻松实现高效管理产品名称:工业行业物联锁系统产品型号:REIB公司全称:宁波瑞奥物联技术股份有限公司公司网址:www.rayonics.com.cn一、研发背景在工业行业用智能门锁电子锁芯的开发过程中,宁波瑞奥物联技术股份有限公司发现,由于锁具内有电路且电池等部件较多,会出现锁具易出故障、维修和维护成本高等问题。因此,企业依托于物联网倾力研发出这样一款产品:将电子部件全部从锁具中移出,锁内仅留一个电子芯片,同时,相应的把所有的电子结构全部放     

X射线荧光光谱分析法及其应用

由于X射线荧光光谱具有选择性高、干扰较小、分析样品不被破坏的特性,应用光谱分析是一种特效性、准确度和灵敏度都很好的一种定量分析方法,因此X射线荧光光谱被广泛应用于各大领域。主要介绍X射线荧光光谱的产生、基本原理和方法,以及在筛选电子电气设备中限制使用物质铅、汞、铬、镉和溴的应用,并对X射线荧光光谱发展进行展望。     

基于生物湿法冶金的废旧印刷线路板金属资源化研究进展

随着科技的快速发展,电子产品数量的急剧增加及其使用周期的不断缩短,全球面临着前所未有的电子废物产生浪潮。一种数量巨大的典型电子废弃物-废旧印刷线路板如何实现绿色、低能耗的处理已成为当前电子废弃物处理中关键问题之一。利用微生物湿法冶金技术将废旧印刷线路板中金属浸出,制备高纯金属,已成为21世纪电子废物处理的前沿技术,同时电子废物的微生物湿法冶金机制探讨已成为近年来的研究热点。本文重点分析微生物湿法冶金处理废旧印刷线路板浸提过程中的微生物种类、影响浸提因素、微生物的浸出机制以及今后需要继续研究的问题。     

废弃电子元器件酸性浸出液中铜的萃取研究

利用国产新型铜萃取剂DZ988,以PEG-NO2/H2SO4混酸溶液氧化浸取废弃电子元器件得到的酸浸液为萃取原液(含铜浓度CCu=3.132 g/L),进行铜的萃取研究,考察各因素对铜的萃取及反萃取的影响。试验结果表明,铜的萃取率随萃取剂浓度、O/A比、萃取温度及pH的提高而提高;在萃取剂浓度设定为25%,萃取料液浓度用氨水调至pH=2,油水比O/A=1:1,常温的条件下,对废弃电子元器件的PEG-NO2/H2SO4混酸浸出液中的铜的萃取率可达99.45%,铜、铁分离系数达1 151;以硫酸作反萃剂,对负载铜的萃取剂进行反萃取研究,在硫酸溶液浓度为250 g/L,相比O/A=1:1时,铜的反萃率接近100%。同时,DZ988基本不萃取Co、Ni,后续可从铜萃余液中继续回收Co、Ni。