连云港春季PM2.5中主要水溶性无机离子污染特征及来源解析

于2017年3月1日—5月31日监测分析了连云港市大气PM_(2.5)中主要水溶性无机离子质量浓度的日变化规律,以及与气象因子、PM10、PM_(2.5)相关性。结果表明,水溶性无机离子质量浓度与环境空气中NO_2、CO、PM_(10)、PM_(2. 5)显著相关,与气温、风速、能见度等呈负相关;日变化呈明显单峰型,峰值出现在08:00左右;水溶性无机离子季度均值为27. 2μg/m~3,占ρ(PM_(2.5))平均50%左右,ρ(NO_3~-)、ρ(SO_4~(2-))和ρ(NH_4~+)占ρ(水溶性无机离子)总85%以上;指出,SO_4~(2-)主要受远距离传输的影响,NO_3~-和NH_4~+主要受局地源的影响。     

饮用水水源地水质监测预警系统设计探讨

以全过程管理监测预警为目标,设计了集数据监测系统、数据传输系统、视频监控系统、预警系统于一体的饮用水水源地水质监测预警系统,为饮用水安全保障提供全过程分层次的决策方案。论述了系统的目标、框架、总体功能、以及涉及的关键技术,积极探索了将水质遥感、GIS技术、无人机技术、生物预警技术应用于饮用水监测预警管理的过程与方法,并指出该系统还需从水文过程-水环境效应的耦合模拟方面加以完善。     

气相色谱-质谱法分析饮用水源水中甲基汞

采用自动固相萃取-气质联用法分析饮用水源中的甲基汞,通过巯基棉小柱萃取大体积(5L)水样后,选择离子扫描方式(SIM)进行定量。实验对比国家标准方法具有更好的线性关系,实际操作简单快捷,灵敏度高。3个浓度水平进行加标回收实验,回收率分别大于71.0%、74.4%、76.0%。对10μg/L浓度重复进样6次,相对标准偏差(RSD)为4.8%。该方法检出限可达到3×10-4μg/L,满足饮用水源水中甲基汞标准限值要求。     

Investigation of carbonyl compound sources at a rural site in the Yangtze River Delta region of China

Carbonyl compounds are important intermediates in atmospheric photochemistry, but their primary sources are still not understood well. In this work, carbonyls, hydrocarbons, and alkyl nitrates were continuously measured during November 2011 at a rural site in the Yangtze River Delta region of China. Mixing ratios of carbonyls and hydrocarbons showed large fluctuations during the entire measurement. The average level for total measured volatile organic compounds during the pollution episode from 25th to 27th November, 2011 was 91.6 ppb, about 7 times the value for the clean period of 7th–8th, November, 2011. To preliminarily identify toluene sources at this site, the emission ratio of toluene to benzene (T/B) during the pollution episode was determined based on photochemical ages derived from the relationship of alkyl nitrates to their parent alkanes. The calculated T/B was 5.8 ppb/ppb, significantly higher than the values of 0.2–1.7 ppb/ppb for vehicular exhaust and other combustion sources, indicating the dominant influence of industrial emissions on ambient toluene. The contributions of industrial sources to ambient carbonyls were then calculated using a multiple linear regression fit model that used toluene and alkyl nitrates as respective tracers for industrial emission and secondary production. During the pollution episode, 18.5%, 69.0%, and 52.9% of measured formaldehyde, acetaldehyde, and acetone were considered to be attributable to industrial emissions. The emission ratios relative to toluene for formaldehyde, acetaldehyde, and acetone were determined to be 0.10, 0.20 and 0.40 ppb/ppb, respectively. More research on industrial carbonyl emission characteristics is needed to understand carbonyl sources better.     

Physico-chemical characterization and source tracking of black carbon at a suburban site in Beijing

Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC (black carbon) samples. TEM (transmission electron microscopy) results indicate that BC from combustion sources shows various patterns, and airborne BC appears spherical and about 50 nm in diameter with a homogeneous surface and turbostratic structure. The BET (Barrett–Emmett–Teller) results suggest that the surface areas of these BC particles fall in the range of 3–23 m²/g, with a total pore volume of 0.03–0.05 cm³/g and a mean pore diameter of 7–53 nm. The nitrogen adsorption–desorption isotherms are indicative of the accumulation mode and uniform pore size. O₂-TPO (temperature programmed oxidation) profiles suggest that the airborne BC oxidation could be classified as the oxidation of amorphous carbon, which falls in the range of 406–490°C with peaks at 418, 423 and 475°C, respectively. Generally, the BC characteristics and source analysis suggest that airborne BC most likely comes from diesel vehicle emission at this site.     

碳源及电子受体对厌氧微生物降解对氯硝基苯的影响

为考察氯代硝基苯的共代谢降解过程中,有机碳源类型和电子受体对氯代硝基苯厌氧降解过程的影响,以对氯硝基苯(p-CNB,para-chloronitrobenzene)为目标污染物,通过间歇试验考察了葡萄糖、乙醇、乙酸钠等有机碳源及SO2--4、NO3等竞争性电子受体对厌氧微生物降解对氯硝基苯的影响。结果显示,葡萄糖、乙醇和乙酸钠作为碳源时,菌种获得的还原能力大小依次为:乙醇葡萄糖乙酸钠。SO2-4对菌种降解对氯硝基苯过程不产生竞争性抑制。NO-3对对氯硝基苯降解过程的影响与碳源的量有关,当乙醇-COD为100 mg/L时,硝酸盐产生竞争性抑制,且抑制作用随着NO-3浓度升高而增强;当乙醇-COD为600 mg/L时,硝酸盐对菌种降解对氯硝基苯过程不产生竞争性抑制作用。     

佳木斯市噪声的信访现状及治理措施

论述了佳木斯市因区域环境噪声质量问题引发的信访案件,并提出了几点治理措施,以达到削减噪声、保护环境、构建和谐社会的目的。     

含酚废水的处理

随着工业化的发展,排向环境中的含酚废水越来越多,由于其具有很强的毒性,目前已经受到国内外广泛关注。因此含酚废水的处理越来越受到人们的关注。本文对含酚废水的来源、危害进行了分析,概述了目前国内处理含酚废水的主要方法,展望了含酚废水处理技术的发展前景。     

商丘市包河沉积物中正构烷烃的分析

采集了商丘市包河6个位点的表层沉积物,用色谱-质谱对正构烷烃进行了分析,利用正构烷烃碳数分布特征和CPI指标等,对该市区的正构烷烃来源进行初步探讨。结果表明,正构烷烃碳数分布范围多数在nC13-nC31之间,分布类型只有一种,即高分子碳范围,碳优势指数为nC29,1相似文献   

沈阳市大气氮氧化物污染状况及控制对策

阐述了沈阳市各类污染源排放废气中NOx排放量所占比例、排放特征,分析了环境空气中NOx的污染状况、各功能区环境空气中二氧化氮浓度差异,污染源排放及其分布、气象条件等因素对沈阳NOx污染分布的影响,并提出确定重点控制行业和地区、建立NOx相应的监测、统计、评估体系、修订和完善环境空气质量标准和一批行业NOx排放标准、应用先进的烟气脱硝技术等几方面的NOx控制对策。