四溴双酚A在土壤中的降解转化及残留研究进展

四溴双酚A(tetrabromobisphenol A,TBBPA)是全球生产量最大的溴代阻燃剂,广泛应用于电子产品和塑料等高分子材料的生产中.由于高的亲脂性及环境稳定性,TBBPA在土壤中易于累积.土壤作为污染物主要的汇之一,污染物在土壤中的环境过程和归趋对正确评价污染物的环境风险至关重要.本文综述了土壤中TBBPA...     

球形障碍物对瓦斯爆燃火焰影响试验研究

为进一步开发煤矿井下瓦斯爆炸事故的隔抑爆技术装备,利用截面为0.2 m×0.2 m的方形管道、纹影仪和高速摄像机,开展无障碍物时和球形障碍物存在情况下的瓦斯爆燃传播试验.研究发现,无障碍物时,密闭管道内爆燃火焰的结构和传播速度受反射压力波的影响很大,湍流火焰、化学反应作用能力与反射压力波的相互作用是造成火焰传播速度变化...     

氢氧化镁/红磷对硅橡胶/黏土纳米复合物阻燃性能的研究

选用甲基乙烯基硅橡胶(MVMQ)和十六烷基三甲基溴化铵(C16BrN)改性的蒙脱土(OMMT)纳米复合材料为原料,以氢氧化镁/微胶囊化红磷(MH/MRP)为阻燃剂,以气相法白炭黑为补强剂,用熔融共混法制备了无卤阻燃MVMQ纳米复合材料。笔者采用XRD表征制备的MVMQ/OMMT纳米复合物的结构,用机械性能测试研究气相法白炭黑和OMMT对MVMQ的协效补强作用,通过极限氧指数、UL94 V垂直燃烧法、环境扫描电镜(ESEM)和热重分析(TG)等分析测试手段研究其燃烧性能和热性能,结合材料宏观燃烧性能的改变,推断OMMT和MH/MRP对MVMQ的阻燃作用机理。     

紫外光固化磷氮类丙烯酸酯的制备及其阻燃性能

报道了多种结构的低粘度多官能团有机磷(甲基)丙烯酸酯的合成,并对其固化膜的阻燃性能和阻燃机理进行了研究,重点讨论了其对于紫外光固化环氧丙烯酸酯和聚氨酯丙烯酸酯固化膜阻燃性能和降解机理的影响,以及有机磷丙烯酸酯体系膨胀机理和阻燃行为.     

Environmental impacts and use of brominated flame retardants in electrical and electronic equipment

Management of waste electrical and electronic equipment (WEEE) or e-waste is becoming a major issue as around 20–50 million tons of such waste is generated worldwide and increasing at a higher rate than other solid waste streams. Electrical and electronic equipment (EEE) contains over 1,000 materials of which brominated flame retardants (BFRs) such as polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) have been the target of the regulators forcing manufacturers to adopt halogen-free flame retardants. As far as these alternatives are concerned, key consideration should be its performance during the whole life cycle through design, use and end-of-life management. The global halogen-free flame retardant movement has reached a point of no return. The most important issue as far as the environment is concerned, for which the transformation to halogen-free retardants was initially targeted, is to make sure that life span of the EEE using the alternatives to BFRs is not shortened thereby resulting in unforeseen increases in e-waste to deal with. The aim of this article is to investigate the environmental issues and current developments related to the use of BFRs in EEE manufacture. It describes the sources, toxicity and human exposure of BFRs, EOL management such as recycling and thermal treatments, exposure of BFRs from e-waste processing facilities and the environment around them and examines the developments and feasibility of the alternatives to BFR in EEE manufacture.     

A chemical and toxicological profile of Dutch North Sea surface sediments

Chemical and toxicological profiles were assessed in surface sediments (fraction <63 μm) from the southern North Sea. In extracts of freeze-dried samples, polybrominated biphenyl (PBB), Irgarol 1051 and phthalate concentrations were below the respective detection limits (except di(2-ethylhexyl)phthalate, which was between 170 and 3300 μg kg⁻¹ dry weight (dw)). Hexabromocyclododecane (HBCD) concentrations were between 0.8 and 6.9 μg kg⁻¹ dw, with highest concentrations at river mouths. Polybrominated diphenylethers (PBDE) concentrations were 0.4–0.6 μg kg⁻¹ dw, decabromodiphenylether (BDE209) 1–32 μg kg⁻¹ dw. The ratio BDE209/PCB153 was used as a tracer for recent emissions, and pointed towards a BDE209 source in the Western Scheldt’s upper estuary. PCBs and PAHs were between 0.19–4.7 and 2.6–200 μg kg⁻¹ dw respectively and generally had highest concentrations at near-shore locations and river mouths.

Responses in the Microtox broad-spectrum and the Mutatox genotoxicity assays were generally low, with near-shore locations giving higher responses. The umu-C genotoxicity and the ER-CALUX assay for estrogenicity showed no response, with the exception of one near-shore location (IJmuiden outer harbour, ER-CALUX).

Highest dioxin-like toxicity (DR-CALUX) was found at near-shore locations, in the outflow of the Rhine/Meuse estuary including a dumping site of harbour sludge. At the Oyster Grounds, DR-CALUX responses appeared to be linked to the occurrence of larger PAHs (4–6 rings). A new, non-destructive clean up procedure resulted in significantly higher DR-CALUX responses than the current protocol. The Dutch legislation on disposal of harbour sludge at sea, dictates the use of the conventional clean up procedure. Our results therefore indicate that probably more dioxin-like toxicity associated with harbour sludge is disposed off at sea than assumed.     

微胶囊化红磷增效氢氧化镁阻燃聚乙烯的燃烧特性

探讨了微胶囊化红磷（MRP）在氢氧化镁（MH）阻燃低密度聚乙烯（LDPE）中的阻燃增效作用,用氧指数和锥型量热计研究了MRP/MH的不同配比对其氧指数、热释放速率、发烟量等燃烧性能参数的影响。试验结果表明在LDPE/MH体系中添加适量的MRP可以有效地提高材料的氧指数,进一步降低材料的热释放速率,延长材料的着火时间,但是材料的发烟量有所增加。从热失重实验结果可以看出,在LDPE/MH体系中添加MRP不仅大大提高材料的初始分解温度,而且具有较好的成炭作用。     

楔形障碍物与火焰的作用

采用多镜头Cranz ＆ Schardin高速摄影机,对卧式燃烧方管内楔形障碍物与CH4/空气预混火焰的相互作用进行了实验研究,获得了高清淅度的障碍物诱导火焰失稳的分幅时序照片.基于RANS方法,对上述复杂物理现象进行了数值模拟.计算结果与实验结果基本相符,反映了火焰在管内传播与变形的详细过程,得到了楔形障碍物所导致的火焰加速与变形的内在机理,揭示了火焰传播过程中由层流燃烧向湍流燃烧转捩的本质.     

塑胶跑道中有机磷酸酯的含量及健康风险

采用超声萃取-层析净化-气相色谱/质谱联用仪定量分析塑胶跑道中7种有机磷酸酯(OPEs),方法回收率为71.41%~110.58%,标准曲线相关系数r0.99,质控良好.采集并分析了成都市12个学校内的塑胶跑道样品中OPEs的含量及分布.结果表明2/3学校内的塑胶跑道样品中检出了OPEs,其中磷酸三正丁酯[tri-n-butyl phosphate,TnBP]、磷酸三异辛酯[tris(2-ethylhexyl)phosphate,TEHP]的检出率较高,而磷酸三(2-氯乙基)酯[tri(2-chloroethyl)phosphate,TCEP]、磷酸三(1,3-二氯异丙基)酯[tridichloropropyl phosphate,TDCPP]、磷酸三苯酯[triphenyl Phosphate,TPh P]在所有样品中均未检测到.Σ7OPEs含量范围为ND~534.89 ng·g~(-1),其中单体含量最高的是TnBP(ND~462.18 ng·g~(-1)).一个样品中检出了毒性较大的氯代磷酸酯-TCPP[trichloropropyl phosphate],含量为205.94 ng·g~(-1).成人和儿童通过皮肤接触摄入的Σ7OPEs日均暴露剂量(以bw计)最高,分别为0.14 ng·(kg·d)~(-1)和0.64 ng·(kg·d)~(-1),儿童的日均暴露剂量明显高于成人.成人及儿童的风险熵值(RQ)为10~(-7)~10~(-5).建议政府对塑胶跑道中OPEs使用量及添加种类进行管控,以更好地保护人群健康.     

Effect of mass fraction of long flame coal on swelling pressure and microstructures of cokes

Long flame coal are abundant and widely distributed in China, but the resource utilization is quite low, the production efficiency is not high. Stamp-charging coke making technology can bend some long flame coal, which can reduce production cost and expand the coking coal resources. The long flame coal of different mass fraction is added into prime coking coal including fat coal from Longhu, 1/3 coking coal from Xinjian and coking coal from Didao in experiment. The swelling pressure is tested on-line detection using pressure sensor in coke making process, and the pores are observed by scanning electron microscopy. The results show that, the swelling pressure first increase and then decrease with the temperature increased and the maximum swelling pressure reduces gradually with mass fraction of the Long flame coal from Shenmu increased in coke making process. The SEM images of resultant coke display that the coke get more and more loose and the amount of pores is increased with mass fraction of the long flame coal from Shenmu increased. The amount pores and the pore diameter both is minimum for coking coal from Didao as prime coking coal under the same fraction of long flame coal.