成都市大气颗粒物的特性研究

以成都市东区为研究区域，研究了该区总悬浮颗粒物（哪）含量及其中重金属的含量随季节变化的特征，通过粉煤灰与哪中重金属含量的关系、富集因子分析来判断颗粒物中重金属的来源。研究表明，TSP及其中重金属的含量随季节变化明显且特征相似；哪的含量严重超标；由监测结果大致推断出了该区域哪及其中重金属的主要来源。     

大气颗粒物化学组成分析

大气颗粒物的化学组成非常复杂,其中包括大量矿质氧化物、可溶性硫酸盐、硝酸盐、海盐、多环芳烃、有机酸和有机氟等。大气颗粒物对局地、区域甚至全球大气辐射平衡、大气能见度、元素的生物化学循环具有重要影响,危害人体健康并参与大气非均相反应。化学组成是决定大气颗粒物各种环境效应的关键因素。国内外对大气颗粒物化学组成分析进行了大量的研究工作。特别是随着气动力学透镜的发展与应用,结合快速、灵敏的光谱和质谱检测手段,适合大气颗粒物化学组成的在线分析方法取得了较大的突破。     

成都地区大气颗粒物中复杂有机物的色谱-质谱分析

〕本文报道了应用气相色谱和气相色谱-质谱联用法对成都地区大气颗粒物中复杂有机物的分析结果。实际分析中共鉴定出77种有机物,首次在成都地区大气颗粒物中发现含有烟碱这一新的污染物。同时对苯并[a]等28种主要污染物做了定量测定。结果表明,成都大气中的有机污染状况非常严重,急待采取有力措施加以改善。     

大气颗粒物的仪器分析方法

对大气总颗粒物和单颗粒物仪器分析方法进行了简要介绍和评述,并对当前研究进展进行了综述,引用文献39篇。     

大气颗粒物重金属环境地球化学研究进展

综述了国内外有关大气颗粒物重金属的研究进展,包括:对大气颗粒物重金属的来源、分布与积累、环境活性、迁移转化、生物毒性等方面的研究成果,并指出了该领域研究中的薄弱环节,展望了今后的研究发展趋势。     

大气颗粒物中六价铬的采样分析

对近几年国内外大气颗粒物中Cr(VI)的采样、样品贮存、Cr(III)与Cr(VI)的分离技术及Cr(VI)的检测手段进行了系统介绍,并对大气中Cr(VI)的在线监测技术进行了初步探讨,为环保、卫生等部门进行大气颗粒物中Cr(VI)的监测及质量控制提供了参考。     

高效液相色谱法测定大气颗粒物中的杂环胺

建立了大气颗粒物中杂环胺的高效液相色谱检测方法.采用ODS C18色谱柱(250 mm×4.6 mm, 5 μm),乙腈-0.01 mol/L三乙胺缓冲溶液(pH 4.0 )为流动相,非线性梯度洗脱,流速1.0 mL/min,柱温30 ℃,紫外检测波长263 nm,并优化荧光激发和发射波长条件,实现了6种杂环胺的基线分离和4种杂环胺的高灵敏度荧光检测.本方法中荧光和紫外检测器的检出限分别为0.0018～0.0084 mg/L和0.093～0.609 mg/L(S/N=3),相关系数在0.9920～0.9999之间,RSD小于5.9%,平均回收率为75.3%～111.6%,回收率相对标准偏差为1.7%～2.3%,具有较高的精确度和准确度.     

大气颗粒物及氧化物对CS_2的催化氧化作用

利用原位ＦＴ－ＩＲ,ＸＲＤ,ＢＥＴ,质谱和连续脉冲微反等手段研究了大气颗粒物及 部分氧化物样品上ＣＳ２催化氧化的反应,并对催化剂的晶化状况和比表面等进行了考 察。结果表明,ＣＳ２在氧化物和大气颗粒物样品上发生氧化反应,生成ＣＯＳ及单质Ｓ,部 分样品上生成ＣＯ２;其中以ＣａＯ的催化作用最为明显,Ｆｅ２Ｏ３次之,Ａｌ２Ｏ３的催化能力有 明显减小,ＳｉＯ２最小,大气颗粒物样品对ＣＳ２有明显的催化氧化作用,活性介于Ｆｅ２Ｏ３ 和Ａｌ２Ｏ３之间;收集的大气颗粒物样品成分主要是Ｃａ（ＡＬ２Ｓｉ２Ｏ８）·４Ｈ２Ｏ,即水泥的主要 成分;ＣＳ２在氧化物或大气颗粒物样品上催化生成ＣＯＳ,是由于催化剂表面吸附氧的作 用．报道了大气颗粒物对ＣＳ２具有催化氧化生成ＣＯＳ的能力,揭示了大气中ＣＯＳ来源 的一个重要途径,对ＣＳ２,ＣＯＳ的污染控制研究具有一定的指导意义．     

测定大气颗粒物中金属含量的样品预处理

通过综合对比实验，从多种样品预处理方法中筛选出测定大气颗粒物中金属含量的样品预处理方法——HNO3-HClO4热消解提取法。该法操作简便、易于掌握，待测金属及其化合物提取率达90%以上（滤筒样品84%以上），而且空白值低，可与化学法及仪器法配套使用。     

大气颗粒物表面的非均相反应

<正>全球空气污染及气候变化的研究中,大气化学一直发挥着核心作用.大气化学研究的三个支柱方法包括实验室研究、外场观测和数值模拟.在过去半个多世纪,大量、系统的大气化学反应动力学实验室研究从分子水平     

阳离子交换树脂分离电感耦合等离子体质谱法测定空气颗粒物中铂族元素

用Dowex AG50W-X8阳离子交换树脂分离空气颗粒物中Pt、Pd、Rh测定的干扰元素Cu、Ga、Hf、Pb、Rb、Sr、Y.模拟标准液实验确定出Dowex AG50W-X8阳离子交换树脂分离流程的最佳条件:上柱HCl浓度为0.8 mol/L,树脂柱床高为4 cm,洗脱速率为1 mL/min.铂族元素分析的国际标准物质BCR-723对照分析表明,Pt、Pd、Rh的测定值与标准值吻合,干扰元素Cu、Ga、Pb、Rb、Sr、Y的分离效率均大于94%,这表明所建立的Dowex AG50W-X8阳离子交换树脂分离流程是可靠的.     

利用代谢组学研究大气细颗粒物的生殖毒性效应

大气细颗粒物(PM2.5)污染已成为严峻的环境问题,探究PM2.5的毒性效应和机理变得尤为重要.本研究利用基于液相色谱/质谱的代谢组学技术,分析经PM2.5悬混液气管滴注暴露后成年雄性大鼠睾丸代谢组的全局变化,采用偏最小二乘判别分析法和非参数检验进行统计分析.结果表明,PM2.5暴露组大鼠睾丸的油提和水提代谢指纹谱均可与对照组实现准确区分,表明PM2.5暴露对大鼠睾丸的整体代谢网络产生了显著影响,最终鉴定出56个差异代谢物.通路分析显示,PM2.5暴露会引起大鼠睾丸的氨基酸和核苷酸代谢紊乱、类固醇激素代谢失衡以及脂类代谢异常,而这些重要通路可能是PM2.5生殖毒性的关键分子事件.     

Djulis (Chenopodium formosanum) and Its Bioactive Compounds Protect Human Lung Epithelial A549 Cells from Oxidative Injury Induced by Particulate Matter via Nrf2 Signaling Pathway

The protective effects of water extracts of djulis (Chenopodium formosanum) (WECF) and their bioactive compounds on particulate matter (PM)-induced oxidative injury in A549 cells via the nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling were investigated. WECF at 50–300 µg/mL protected A549 cells from PM-induced cytotoxicity. The cytoprotection of WECF was associated with decreases in reactive oxygen species (ROS) generation, thiobarbituric acid reactive substances (TBARS) formation, and increases in superoxide dismutase (SOD) activity and glutathione (GSH) contents. WECF increased Nrf2 and heme oxygenase-1 (HO-1) expression in A549 cells exposed to PM. SP600125 (a JNK inhibitor) and U0126 (an ERK inhibitor) attenuated the WECF-induced Nrf2 and HO-1 expression. According to the HPLC-MS/MS analysis, rutin (2219.7 µg/g) and quercetin derivatives (2648.2 µg/g) were the most abundant bioactive compounds present in WECF. Rutin and quercetin ameliorated PM-induced oxidative stress in the cells. Collectively, the bioactive compounds present in WECF can protect A549 cells from PM-induced oxidative injury by upregulating Nrf2 and HO-1 via activation of the ERK and JUN signaling pathways.     

Characterization and Identification of Polycyclic Aromatic Hydrocarbons in Diesel Particulate Matter

Emission of toxic exhaust from diesel engines is one of the major problems associated with the use of petroleum fuels. Particulate matter emission is perceived as a major pollutant, detrimental to the human health and environment, and has led to considerable study. Vehicular emissions comprise toxic pollutants that include unburnt hydrocarbons, polycyclic aromatic hydrocarbons, dioxins, and others. In this study, experiments have been carried out with the objective of determining overall particulate matter chemical composition and size. Electron microscopic images of the emitted soot were studied for average particle size distribution. More than 50 percent of the particles were in the range of 25 to 35 nanometers. Approximately 7, 9, 16, and 5 percent of the measured particles were from 35 to 40, 40 to 45, 45 to 50, and 50 to 55 nanometers, respectively. Determined elements were Al, Ba, Ca, K, Mg, Ti, Zn, and Zr at concentrations of 727, 53, 1100, 701, 1145, 638, 177, and 800 micrograms per milliliter respectively. Fifteen polycyclic aromatic hydrocarbons were detected in the extracts of filters and their concentrations were estimated. This investigation allows the comparison of particulate matter from different fuels and their blends.     

工业废水中溶解态有机物分析方法研究

采用0．45μm玻璃纤维滤膜将工业废水分离为悬浮态和溶解态有机物质,以二氯甲烷为萃取剂,采用液液萃取一气质联用法对工业废水中溶解态有机物进行测定。优化的最佳萃取条件为：每个pH范围各萃取2次,静置时间5min,氯化钠加入量15g。方法的加标回收率为91．1％～103％,测定结果的相对标准偏差小于5％fH=6）。该法分析时间短,易于操作。     

单颗粒气溶胶飞行时间质谱仪在细颗粒物研究中的应用和进展

单颗粒气溶胶质谱技术起源于20世纪70年代,在近二十年得到了快速的发展.单颗粒气溶胶飞行时间质谱仪具有高时间分辨率,且同时测量大气中单个细颗粒物粒径、多种化学组分和混合状态的特点,在大气细颗粒物监测和科学研究中逐渐得到了广泛应用.本文对单颗粒气溶胶飞行时间质谱仪的发展历程进行了介绍,对目前已商品化的单颗粒气溶胶飞行时间质谱仪ATOFMS和SPAMS的原理、数据分析方法、结果输出方式以及在环境监测和研究中的主要应用进行了总结,并指出单颗粒气溶胶飞行时间质谱仪的发展方向.     

Effect of Aucubin-Containing Eye Drops on Tear Hyposecretion and Lacrimal Gland Damage Induced by Urban Particulate Matter in Rats

Exposure to particulate matter is a causative factor of dry eye disease. We aimed to investigate the beneficial effect of eye drops containing aucubin on dry eye disease induced by urban particulate matter (UPM). Dry eye was induced in male SD rats (6 weeks old) by topical exposure to UPM thrice a day for 5 d. Eye drops containing 0.1% aucubin or 0.5% aucubin were topically administered directly into the eye after UPM exposure for an additional 5 d. Tear secretion was evaluated using a phenol red thread tear test and corneal irregularity. The oxidative damage in the lacrimal gland was evaluated using TUNEL and immunohistochemical staining. The topical administration of aucubin significantly attenuated UPM-induced tear hyposecretion (control group: 9.25 ± 0.62 mm, UPM group: 4.55 ± 0.25 mm, 0.1% aucubin: 7.12 ± 0.58 mm, and 0.5% aucubin: 7.88 ± 0.75 mm) and corneal irregularity (control group: 0.00 ± 0.00, UPM group: 3.40 ± 0.29, 0.1% aucubin: 1.80 ± 0.27, and 0.5% aucubin: 1.15 ± 0.27). In addition, aucubin also reduced the UPM-induced apoptotic injury of lacrimal gland cells induced by oxidative stress through the increased expression of HMGB1 and RAGE. These findings indicate that the topical administration of aucubin eye drops showed a beneficial effect against UPM-induced abnormal ocular changes, such as tear hyposecretion and lacrimal gland damage. Therefore, our results reveal the pharmacological activities of aucubin in dry eye disease.     

Determination of Chromium (VI) in Airborne Particulate Matter by Electrothermal Atomic Absorption Spectrometry

Hexavalent chromium Cr(VI) is a well-established carcinogen associated with lung, nasal, and sinus cancer. Cr(VI) threshold limit values in workroom air have been recently lowered. Consequently, the currently available analytical methods are insufficiently sensitive or high cost. In this paper, a simple, cost-effective, sensitive, and reproducible method using solid-phase extraction with electrothermal atomic absorption spectrometry for determination of hexavalent chromium in airborne samples is reported. The method validation included selectivity, linearity, accuracy, and precision. Interferences from other ions likely to be present in airborne samples, including trivalent chromium, were tested and selectivity was demonstrated. The detection and quantification limits were, respectively, as low as 0.1 and 0.4?µg?L^?1. The linearity ranged from 0.5 to 50.0?µg?L^?1, with a regression coefficients exceeding 0.998. The extraction recovery exceeded 98%. The developed method was successfully compared with a reference spectrophotometric method. The performances achieved were similar to ion chromatography and high-performance liquid chromatography approaches. The novel method was tested on airborne samples collected from the workplace. The method’s performance suggests that it may be an alternative to high-cost techniques for monitoring occupational exposure to hexavalent chromium.     

石墨探针采样／石墨炉原子吸收光谱测定大气微粒物质中的痕量铁

采用一定规格的石墨探针直接收集大气微粒物质，并采用原子吸收光谱法测定其中的痕量铁。     

The Distribution of Total Particulate Matter (TPM) And Nicotine Between Mainstream and Sidestream Smoke in Bidis and Cigarettes

ABSTRACT

The mainstream (MS) and sidestream (SS) smoke of three types of popular Indian cigarettes, a brand of low tar Indian cigarettes, a brand of US cigarettes and two brands of popular Indian bidis were analysed for carcinogenic total particulate matter (TPM) and nicotine levels employing standard smoking conditions and/or modified smoking standards.

The analysis clearly demonstrated relatively higher levels of TPM and nicotine in MS of three types of popular Indian cigarettes when compared with a brand of low tar Indian cigarettes or a brand of US cigarettes or reported values for MS of western cigarettes. This was also reflected in MS/SS ratios of TPM and nicotine as TPM and nicotine levels in SS of Indian and US cigarettes were similar, when tested employing standard smoking conditions.

Comparative analysis of Indian bidis/cigarettes and a brand of US cigarettes employing modified smoking standard (i.e. 2 puffs/min instead of 1 puff/min) revealed significantly lower values of TPM and nicotine in SS of Indian bidis when compared with corresponding values in Indian/US cigarettes. This shows that contribution of TPM and nicotine in SS from a single bidi to environmental tobacco smoke (ETS) is very much less than that of a single cigarette, and contribution of SS from Indian and US cigarettes to ETS appear to be similar. Reduced levels of TPM and nicotine in SS of bidis, probably due to lack of added burning agents, result into relatively higher deliveries of TPM and nicotine in MS as reflected by higher MS/SS values.