共查询到17条相似文献,搜索用时 203 毫秒
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消费品安全委员会(CPSC)组织的一个专家小组得出结论认为聚氯乙烯增塑剂二异壬基邻苯二甲酸酯(DINP)对人群不构成危险.虽然在动物试验中DINP会致癌和生殖器官变形,但人群接触量非常低,不会有这种危险. DINP用作聚氯乙烯(PVC)玩具和其他产品的增塑剂.每天玩玩具3h的小孩的最大接触剂量可达每天每公斤体重0.28mgDINP,而可接受日摄入量是每天每公斤0.12mg,因此对每天玩75min以上的小孩可能有危险,但对大多数小孩,接触PVC玩具基本上不会有什么危险. 1988年,CPSC曾要求玩具工业停用DINP,那时玩具工业改用柠檬酸盐作增塑剂或转向聚… 相似文献
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二(2-乙基己基)己二酸酯(DEHA)是一种广泛使用的增塑剂,而其作为一类生物内分泌干扰素,长期大量使用会对人类和环境造成不良影响。综述了国内外DEHA的检测方法,包括样品前处理技术和检测技术,其中前处理技术主要有索氏提取法、超声提取法、同位素稀释法、顶空萃取法、液液萃取法、固相微萃取法、微波萃取法等,分析技术主要有光谱分析法、气相色谱分析法、液相色谱分析法及其联用分析法等;对不同检测方法的原理、特点及应用进行综述和对比,提出后续研究可从筛选液液萃取的萃取剂类型并联合超声等萃取技术,提高复杂样品体系中DEHA检测能力以及研发便携化、智能化检测仪器等方面开展。 相似文献
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壳聚糖水果保鲜膜的应用探讨 总被引:5,自引:0,他引:5
研究以壳聚糖为主料制备壳聚糖膜的方法,用这些膜分别在常温和低温(3℃)条件下进行水果保鲜.对不同封膜体系的失水率、二氧化碳含量变化、总酸和总糖变化量进行定量测试和对比,结果表明复合金属离子的壳聚糖膜的保鲜效果要优于纯壳聚糖膜、日本保鲜膜和普通PVC膜,其中,复合锌离子的壳聚糖膜的保鲜效果最好.本文对壳聚糖膜的保鲜机理进行了初步的探讨.实验表明,复合金属离子的壳聚糖膜是一种既可保鲜又可为人体补充微量元素的绿色可食水果保鲜膜. 相似文献
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以泰乐菌素(TYL)为目标有机污染物,系统研究了两种微塑料聚乙烯(PE)和聚氯乙烯(PVC)对泰乐菌素的吸附动力学与热力学.结果表明:PVC对泰乐菌素的吸附大于PE;吸附在36h可完全达到平衡,吸附动力学可以用二级动力学较好的拟合;颗粒扩散模型表明表面吸附和颗粒扩散是PE和PVC对TYL吸附的主要机理;吸附等温线可以用Henry模型较好拟合,说明泰乐菌素在PE和PVC上的吸附存在明显的线性分配规律,吸附热力学表明吸附过程是自发进行的;本研究可以为科学合理的评价微塑料在环境中的行为及其对环境中污染物的迁移转化的影响提供理论依据. 相似文献
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油,是我们每个人一日三餐都要吃的食品。日常食用油大部分是从市场上购买的塑料桶装食用油。在一些大城市,各大超市每天可销售成百上千桶塑料桶装油,但从来没人想到过用塑料桶装油会有什么问题。最近国内一项最新科研成果表明,塑料桶装食用油中会溶进对人体有害的增塑剂。 相似文献
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作为最普遍使用的增塑剂Di-(2-ethylhexyl)-phthalate(DEHP.邻苯二甲酸二异辛酯)因Polyvinyl chloride(PVC,聚氯乙烯)在人类生活中被广泛应用而在环境中到处存在,已成为一种公认的环境污染物。阐述了DEHP通过日常生活、饮食、药物、母乳及医疗设备等途径对婴儿健康的危害程度。通过定量数据分析了婴儿接触DEHP的安全尺度。指出研究已经证实婴儿与成人对DEHP有着不同的药物代谢动力学和新陈代谢,婴儿是受DEHP危害最敏感的人群。 相似文献
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为探明微塑料和重金属复合污染对作物种子萌发与生长的影响,以玉米种子为对象,探究了铅(Pb)和3种微塑料[聚乙烯(PE)、聚丙烯(PP)、聚氯乙烯(PVC)]不同单一及复合浓度暴露对玉米种子萌发及其生长的影响.结果表明,Pb单一暴露对玉米种子发芽的抑制总体上随其浓度的升高而增强;与CK相比,500、 1 000和1 500 mg·L-1PE暴露显著抑制玉米种子发芽,100 mg·L-1和300 mg·L-1暴露影响不显著(第5 d除外);所有PP浓度暴露均显著抑制玉米种子发芽;相比PP和PE,PVC单一暴露对玉米发芽抑制较轻.Pb和3种微塑料复合暴露均显著抑制玉米种子发芽,随着时间的增长,抑制逐渐减弱.玉米种子的发芽指数、发芽势和活力指数均随着Pb及3种微塑料单一暴露浓度升高而减小,且在Pb和PE复合暴露下较CK显著减小,但在Pb和PP、 Pb和PVC复合暴露下均无显著变化;3种微塑料中,PVC对玉米种子活力影响相对最轻.10 mg·L-1Pb和100 mg·L-1的3种微塑料单... 相似文献
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研究了目前给水管网中常用的3种塑料管材,未增塑聚氯乙烯(uPVC),聚乙烯(PE)和无规共聚聚丙烯(PPR)管在输配水过程中有机物的释放规律.通过静态管段实验模拟给水管网中不同输配水状态,选取总有机碳(TOC)为综合评价指标,考察了不同塑料管材中有机物随时间的迁移释放特性,并分析了管材有机物释放对管网水中余氯消耗的影响.随着管材输配水次数的增加,uPVC管释放至水中的TOC浓度和TOC释放速率分别在0.03mg/L和0.04μg/(d?cm2)以下,而PE管和PPR管在输配水过程中TOC的释放浓度和释放速率在初期最大[PE: 0.19mg/L,0.25μg/(d?cm2);PPR:0.07mg/L,0.09μg/(d?cm2)],且后期递减并趋于平稳[PE:0.03~0.08mg/L,0.05~0.10μg/(d?cm2);PPR:0.01~0.03mg/L, 0.01~0.04μg/(d?cm2)].随着水力停留时间的增加,不同管材释放的有机物浓度持续升高.不同管材有机物的释放能力排序为:PE>PPR>uPVC.各管材的有机物释放特性直接影响管网水的余氯消耗特性,且管材的有机物释放量越多,管网水的余氯消耗越快.PE管的使用易引起水体有机污染问题.本研究明确了3种常用塑料管材的有机物释放规律,将进一步为与塑料管材安全性能评价相关的国家标准的修订提供理论依据. 相似文献
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比较了聚氯乙烯(PVC)、聚苯乙烯(PS)和聚乙烯(PE)3种热塑性塑料,来固化焚烧炉灰和废阳树脂的工艺条件,固化体的物化性及耐辐照等性能。各种塑料固化体,经过抗压强度、浸出率、反复冷冻和加热、大气老化、浸渍和10^6GY辐照等试验,仍保持性能稳定,能满足要求;其中,利用废放免管(PS)固化剂包容炉灰的固化体,机械性能较好,减容比较大,为处理放射性固体废物开辟了一条以废治废的新途径。 相似文献
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Eco-efficiency analysis was used to compare eco-effectiveness of PVC plastisol with two commercially accepted coating agents; polyacrylate (PAA) and polyurethane (PUR) both in dispersed form in water. Eco-efficiency portfolio was graphically illustrated for different scenarios of coating textile fabrics using high and low quality PVC plastisols. PVC plastisol was found as the most eco-efficient coating agent followed by polyacrylate and polyurethane resin dispersions in water. It was concluded that PVC plastisol containing non-toxic plasticizer and less than 5 ppm free vinyl chloride monomer is an eco-efficient material which, when responsibly managed from cradle to grave, provides sustainable benefits to the society. 相似文献
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Joy Onasch Paul ShoemakerHoa Mai Nguyen Cora Roelofs 《Journal of Cleaner Production》2011,19(5):408-413
The Toxics Use Reduction Institute (TURI), Boston Public Health Commission (BPHC), and Vietnamese American Initiative for Development (Viet-AID) have worked with small business sectors to reduce their use of toxic chemicals. Three cases, described here, in dry cleaning, auto shops and floor finishing share common approaches for creating successful models of effective dissemination of toxics use reduction in small businesses. These include direct business support, peer-to-peer training and promotion of alternatives, and collaborations with stakeholders to achieve greener businesses. These results were achieved despite predictable barriers of lack of resources, suspicion of safer alternatives, and language and cultural barriers. 相似文献
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《Journal of Cleaner Production》2008,16(16):1764-1776
Single-use medical devices have been under close scrutiny for several years, especially the choice of plastic materials. Many different requirements such as medical safety, treatment functionality and efficiency, environmental performance, etc. have to be fulfilled. Today, the most commonly used materials for hydrophilic urinary catheters are polyvinylchloride (PVC) and thermoplastic polyurethane (TPU). In this research study, these two materials' environmental performance was evaluated. In light of the knowledge gained in that study a new plastic material for use in urinary catheters was developed. The aim of the development of this new material was to design a high performance material with superior environmental performance. The newly developed plastic material is a polyolefin-based elastomer. The ecological environmental performance of the new material was evaluated and compared to the existing plastic materials. The study focused exclusively on the choice of plastic materials and their ecological environmental performance.The analysis has been performed using a system perspective and a life cycle assessment (LCA) methodology. The functional unit has been set to the treatment of one patient during one year. The results from the LCA models have been presented both in terms of direct inventory data, such as energy use and formed emissions, and in terms of the results from four different impact assessment methods. Analysis of the results based on direct inventory data, i.e. common inventory results such as energy resource uses and emissions of CO2, NOx and SO2 show an overall better environmental performance for the new polyolefin-based elastomer compared to the existing PVC and TPU plastic materials. The normalization and weighting steps in the analyzes have indicated the importance of energy resource uses and global warming as indicator for the environmental performance even if other impact categories also can play a role. In the environmental impact assessment, the polyolefin-based elastomer showed a clearly better environmental performance than the TPU material. Compared to PVC plastic material the new polyolefin-based elastomer showed an almost equivalent environmental performance. This can be mainly explained by the different materials' energy use. The new material has thus also shown to be an environmentally good alternative to PVC if a PVC-free material is requested. Basing the plastic formula, on simple bulk plastics with low energy use in the production of single-use medical devices, has been shown to be a successful method of producing high quality products with superior environmental performance. 相似文献
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以内分泌干扰物17α-乙炔基雌二醇(EE2)作为目标污染物,系统研究了5种微塑料聚酰胺(PA)、聚乙烯(PE)、聚氨酯(TPU)、聚氯乙烯(PVC)和聚苯乙烯(PS)对EE2的吸附动力学、吸附等温线及解吸作用.微塑料对EE2的吸附动力学和吸附等温线的结果表明,5种微塑料对EE2的吸附能力为PA>TPU>PE>PVC>PS;5种微塑料中TPU和PA具有最大的吸附能力和吸附容量,主要归因于氢键产生的化学吸附;而PE、PS、PVC主要是依靠范德华力的相互作用.因PA和TPU对EE2的吸附能力更强,两者的解吸量均高于其他3种物质.采用解吸率来反映不同微塑料的解吸性能,发现EE2在PS中的解吸率最高,PA和TPU上解吸率相对较低.采用单因素重复测量方差分析统计学方法对EE2在5种微塑料上的解吸特性进行分析,EE2在PS与其他4种微塑料之间表现为显著性差异,其余微塑料两两之间无显著性差异;尽管肠胃液中解吸率高于去离子水,但两者并无显著性差异. 相似文献
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Global challenges have exacerbated a search for solutions to poverty and environmental degradation. Integration it was argued would help address the twin challenge. Integrated Water Resources Management (IWRM) was supposed to be that magic bullet and was embraced by scientists because of the clinical efficiency with which it argued for integrated analysis of sectors and resources and of systems and scale conditions. This paper argues that effective implementation of the Water-Energy-Food (WEF) Nexus can be supported by robust science. The corollary that robust science automatically leads to effective implementation is not always known to be true. The nexus approach sheds light on the challenges of implementation by introducing concepts of trade-offs and thresholds and consequently emphasizes the importance of transdisciplinary approaches to sustainable development. This paper reviews the results of recent research to offer tentative answers to the following questions: (a) Why is the governance dimension important to undertake an integrated analysis of water-energy-food challenges? (b) What does the nexus approach connote in normative and institutional terms? (c) What does implementation mean in nexus terms? (d) How can we establish if the nexus approach is an improvement over business as usual? and (e) What tools are available that would enable translation of results of scientific research to create an evidence base that would enable decision makers to act in support of sustainable development? 相似文献