广州市居民家庭室内灰尘中传统和新型阻燃剂与塑化剂的污染特征及健康风险评估

近年来,随着阻燃剂多溴联苯醚(PBDEs)和以邻苯二甲酸酯(PAEs)为代表的传统型塑化剂(LPs)的逐步禁用或限用,有机磷系阻燃剂(PFRs)等新型阻燃剂及替代型塑化剂(APs)的生产和使用呈逐年增长的趋势,其环境污染特征和人体暴露健康风险值得引起广泛关注.目前,灰尘已广泛用于室内环境中PBDEs、PFRs和LPs等半挥发性有机污染物(SVOCs)的污染特征评估,而关于室内灰尘中APs的污染特征则鲜有报道.本研究以广州市42户普通居民家庭为研究对象,采集家庭室内灰尘并分析了PFRs、PBDEs、LPs和APs的含量及组成特征.结果表明,PFRs、PBDEs、LPs和APs在室内灰尘中均有广泛检出,其含量分别为593.28～11531.56、13.45～27029.13、40494.83～1154497.16和15365.19～1013352.51 ng·g^-1.大多数家庭中,PFRs和部分APs在灰尘中的含量呈现高于PBDEs和LPs的特征,PFRs和APs等新型污染物的人体暴露健康风险需引起高度关注.采用暴露模型评估人体经灰尘摄入和皮肤接触对目标污染物的日均暴...     

剑麻纤维基多孔炭材料的制备及其吸附氯苯的研究

以剑麻纤维为原料,通过简易的一步炭化活化法制备了一系列多孔炭材料,分别探究了3种温和的金属盐活化剂、活化剂与剑麻纤维的质量比和活化温度对炭材料的氯苯吸附量的影响,并通过BET、SEM、XRD、Raman、FT-IR、元素分析等手段表征其物理化学性质.结果表明,当采用CuCl₂为活化剂、CuCl₂与剑麻纤维的质量比为10∶1及活化温度为800℃时,制备得到的剑麻纤维基多孔炭(PCC)吸附性能最佳,其在氯苯浓度为1560 mg·m^-3时,吸附量达到856 mg·g^-1,而未经CuCl₂活化的炭材料(PC)的氯苯吸附量仅为15 mg·g^-1.氯苯吸附性能的提升主要归因于比表面积、孔容、无序性和表面含氧官能团的增加.此外,采用巨正则系综蒙特卡洛(GCMC)方法模拟氯苯分子在制备的多孔炭材料中的吸附行为,结果表明,该材料中孔径为0.5 nm的孔对氯苯分子的吸附能力最强,且对氯苯吸附起主导作用的为苯环中心和Cl原子与炭材料上连接含氧官能团的H原子之间的静电作用力.     

深圳市纯电动泥头车减污降碳协同效益评价研究

新能源汽车替代传统燃油车是减缓能源与环境压力并如期实现“双碳”目标的重要途径,但在重型车辆、工程车等领域推广较为缓慢.深圳市自2019年开始推广使用纯电动泥头车,并计划到2025年新能源环卫、泥头车数量达到8000辆.为深入探究纯电动泥头车替代柴油泥头车所产生的减污降碳协同效益,本研究基于一手调研数据,采用生命周期评价方法并结合GREET模型,对比分析了两类泥头车在燃料周期、车辆周期和配套设施周期3个周期内的能耗、主要空气污染物及碳排放情况.结果表明,纯电动泥头车全生命周期内能耗较柴油泥头车可减少36.2%,主要污染物如NO_x、SO₂、VOC和PM_2.5降幅分别达81.3%、37.8%、29.0%和25.9%;温室气体(GHGs)排放强度减少14.4%,基准情境下2030年和2050年推广纯电动泥头车GHGs累计减排量分别为71.4万t和258.5万t.尽管节能减排效果显著,但其初始购置和售后维保成本过高是制约其推广的最主要因素,通过降低车辆及电池生产制造成本、提高充换电设施数量及售后维保能力等有望加快泥头车纯电动化.     

pH值、硫酸根和温度对钢管管垢中铬释放的影响

以市政供水管网钢管管垢为研究对象,将垢层由外向内分为表层、硬壳层和疏松多孔层.利用SEM、BET、XRD、XPS和分形态提取等技术对预吸附Cr(Ⅵ)前后的各层管垢进行表征和分析,并探究了pH值、SO₄^2-浓度和温度对各层管垢中Cr释放的影响.结果显示,钢管各层管垢的主要成分均为α-FeOOH,吸附性能排序为表层>疏松多孔层>硬壳层,管垢中铁元素大多以三价和二价形式存在,具有一定还原性.Cr(Ⅵ)通过物理和化学吸附富集于管垢,主要以铁锰氧化物结合态存在,表层管垢富集量最大.酸性环境、SO₄^2-浓度和温度的升高均会促进Cr的释放.强酸性条件下表层Cr释放浓度为中性条件下的2.76倍;SO₄^2-浓度增加使各层管垢的Cr释放量增加0.1～0.4倍;温度升高20℃,表层管垢的Cr释放量增加26.74%.     

磷酸三(1,3-二氯-2-丙基)酯导致小鼠神经毒性结局的潜在靶点研究

磷酸三(1,3-二氯-2-丙基)酯(TDCPP)在环境介质及生物样本中被广泛检出,为探究TDCPP的潜在神经毒性以及作用机制,以C57BL/6小鼠为动物模型,考察经300 mg·kg-1·d-1的TDCPP持续染毒35 d后,小鼠大脑皮层神经功能相关因子及血清代谢组学的变化.结果显示,小鼠在TDCPP染毒35 d后,大...     

压气机叶片用耐冲刷防腐有机涂层的制备及性能研究

目的 提高压气机叶片有机涂层的耐冲刷和防腐性能.方法 以氨基改性环氧树脂为粘接剂,通过加入高硬度Al2O3填料以及其他着色、防锈颜料,并充分分散,制备一种具有耐冲刷防腐功能的有机涂层.通过摆杆硬度测试、磨耗测试、冲刷测试、腐蚀测试及其他力学性能测试,对耐冲刷防腐有机涂层的综合性能进行评价,对比高硬度Al2O3填料含量对...     

Aldehyde and Monocyclic Aromatic Hydrocarbon Mixing Ratios at an Urban Site in Las Vegas,Nevada

ABSTRACT

Linhong Jing completed a master's degree in chemistry at UNLV and is currently enrolled in the Ph.D. program at Purdue University. Her address is Department of Chemistry, Purdue University, West Lafayette, IN 47907. Dr. Spencer Steinberg is an associate professor of chemistry at UNLV. His address is UNLV Department of Chemistry, P.O. Box 454003, Las Vegas, NV 89154-4003. Dr. Brian Johnson is an associate professor of chemistry at UNLV. His address is UNLV Department of Chemistry, P.O. Box 454003, Las Vegas, NV 89154-4003.

Oxidation of benzene, toluene, ethylbenzene, and xylenes (BTEX) in air, of significance due to, for example, the potential for O₃ formation, is believed to be initiated by OH attack on the ring (addition) or on the alkyl side chain (H abstraction). A series of ring-breaking reactions follows, with major products predicted to be a-dicarbonyls, simple aldehydes, and organic acids. To test this prediction, ambient air mixing ratios of aldehydes (formaldehyde, ac-etaldehyde, benzaldehyde, glyoxal, and pyruvaldehyde), along with some supporting BTEX data, were measured at an urban site in Las Vegas, NV. Samples were collected on sorbents and determined by chromatographic methods; mixing ratios were compared to ambient levels of CO, O₃, and NO_x. A meteorological analysis (temperature, wind speed, and wind direction) was also included. Statistically significant relationships were noted among the BTEX hydrocarbons (HCs) and among the photochemi-cally derived species (e.g., O₃, NO₂, and some of the aldehydes), although there was seasonal variation. The observations are consistent with a common primary source (i.e., vehicular exhaust or fuel evaporation) for the BTEX compounds and a common secondary source (e.g., OH attack) for glyoxal and pyruvaldehyde.     

The drivers of risk to water security in Shanghai

Big cities are often said to have big water problems, and Shanghai is no exception. In this paper, we examine and compare the influence of the major factors that give rise to the risk of water insecurity in Shanghai. There is an extensive and diverse literature on these issues, dealt with in isolation, and here, we provide a synthesis of the literature, together with our own assessments and calculations, to assess what are the risks to Shanghai’s water supply and what is our degree of confidence in this assessment. We describe the systems that supply water to the city, and past and future changes in the systems, including changes in the glaciers that supply some water to the river, changes in climate, changes in land use, the construction of dams, and water diversions. We show how, at the same time as Shanghai is increasing its dependence on the Yangtze river, water diversions and sea level rise are increasing the risk that this water will be too saline to consume at certain times of the year. This analysis suggests that most of the major drivers of the risk to water security in Shanghai are within the power of environmental managers to control.     

基于系统安全观的道路交通安全立法体系重构研究

介绍和分析现代道路交通安全治理的3种思想。应用其中非常值得我国借鉴的系统治理思想对现行道路交通安全立法进行分析。现行道路交通安全立法仅围绕驾驶人的行为控制而设计,围绕道路交通安全管理部门的职能而展开,在很大程度上局限于道路交通秩序管理,在体系上存在缺失,影响道路交通安全治理的工作及其成效。基于当前形势分析,我国有必要也有条件借鉴道路交通安全系统治理的先进思想,重新构建道路交通安全立法的体系。该体系的重构需从道路安全保障、车辆安全保障、交通秩序管理、运输安全运营、交通事故处理等5个方面展开。     

新疆乡镇企业经济与生态环境保护协调发展战略的探讨（二）

文中论述了新疆地区乡镇企业发展与生态环境有关的产业结构特点和分布,分地区、分行业计算了乡镇工业1985—1988年的“三废”污染和生态破坏状况,并对1995年和2000年“三废”污染控制数量及生态—经济规划指标作了综合评述。提出了新疆乡镇企业经济与生态环境保护协调发展战略的主要对策和建议。