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371.
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重庆市主城区不同粒径颗粒物水溶性无机组分特征 总被引:13,自引:2,他引:13
于2010年3月—2011年7月,在重庆市主城区同步采集PM1.0、PM2.5和PM10三种粒径的颗粒物样品. 用离子色谱分析了样品中F-、Cl-、NO3-、SO42-、Na+、NH4+、K+、Mg2+和Ca2+ 9种水溶性无机组分,并收集了SO2和NO2等气体污染物的数据. 结果表明:采样期间ρ(PM1.0)、ρ(PM2.5)和ρ(PM10)分别为82.9、104和160 μg/m3,PM1.0、PM2.5、PM10中所测9种水溶性无机组分的浓度之和分别为40.82、48.66和57.99 μg/m3. ρ(SO42-)、ρ(NO3-)和ρ(NH4+)相对较高,并且主要分布在细颗粒物中. 多数水溶性无机组分浓度冬季最高,春季其次,夏、秋季浓度偏低. 所测组分溶液的pH显酸性,冬季样品的pH最低,细粒子的酸性要强于粗粒子. SOR(硫的氧化率)与NOR(氮的氧化率)与国内其他地区相比较高,SOR秋季最高,NOR冬季最高. 因子分析结果表明,化石燃料以及生物质的燃烧、机动车尾气排放是水溶性无机组分的主要来源,建筑施工、土壤风沙等扬尘类污染源对水溶性无机组分也有一定的贡献. 相似文献
373.
Recep Kulcu Kamil Ekinci Fatih Evrendilek Can Ertekin 《Environmental monitoring and assessment》2010,167(1-4):545-558
This study quantified spatiotemporal patterns of CH4 and N2O emissions from livestock and poultry production in Turkey between 1961 and 2007. CH4(enteric) (from enteric fermentation), CH4(manure) (from manure management), and N2O(AWM) (from animal waste management) emissions in Turkey were estimated at 1,164, 216, and 55 Gg in 1961 and decreased to 844, 187, and 39 Gg in 2007, contributing a share of roughly 2% to the global livestock-related CH4 emissions and %1.5 to the global N2O(AWM) emissions, respectively. Total CO2-eq emissions were estimated at 50.7 Tg in 1961 and declined from a maximum value of 60.7 Tg in 1982 to a minimum value of 34.5 Tg in 2003, with a mean emission rate of 48 Tg year???1 due to a significant reduction in the number of ruminant livestock. The highest mean share of emissions belonged to West Black Sea (14% and 16%) for CH4(enteric) and CH4(manure) and to North East Anatolia (12% and %13) for N2O(AWM) and total CO2-eq emissions, respectively. The highest emission density was 1.7 Mg km???2 year???1 for CH4(enteric), 0.3 Mg km???2 year???1 for CH4(manure), and 0.07 Mg km???2 year???1 for the total CO2-eq emissions in the West and North East Anatolia regions and 0.09 Mg km???2 year???1 for N2O(AWM) in the East Marmara region. Temporal and spatial variations in CH4(enteric), CH4(manure), and N2O(AWM) emissions in Turkey were estimated using regression models and ordinary kriging at a 500-m resolution, respectively. 相似文献
374.
Zehra Semra Can Melike Fırlak Aslıhan Kerç Serkan Evcimen 《Environmental monitoring and assessment》2014,186(1):525-539
Endocrine-disrupting compounds (EDCs) are exogenous substances that cause adverse health effects in an intact organism, or its progeny, subsequent to the changes in endocrine function. Recent studies have shown that wastewater treatment plant effluents play an important role in the release of EDCs into aquatic environments. Therefore, in this study, influent and effluent samples from three different wastewater treatment plants (WWTPs) in Istanbul were analysed for the presence of the principal EDCs. These chemicals include steroids and synthetic organic chemicals. Thus, the occurrence and fate of EDCs of great health concern were monitored at three WWTPs in Istanbul. Furthermore, these WWTPs are employing different treatment processes. Therefore, the EDC removal performances of different treatment regimes were also evaluated. Phytosterol was the most abundant EDC in the influent samples. Second group of compounds at high influent levels were alkyl phenols. Pesticide levels of all three WWTP influent samples were low. Pasakoy Advanced WWTP is more effective at eliminating EDCs. Kadikoy Primary WWTP exhibits the lowest EDC elimination efficiencies. To the best of our knowledge, this work comprises the first detailed report on the occurrence and behaviour of both natural and synthetic EDCs in WWTPs of Istanbul and Turkey. The steroid estrogen levels of this study are higher than the previously documented values, except the levels given for Gaobeidian WWTP in Beijing, China. This is attributed to higher population densities of Beijing and Istanbul and as well as to lower individual water consumption rates in the two cities. 相似文献
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重庆市区灰霾天气变化及特征分析 总被引:1,自引:0,他引:1
分析了近15年重庆市区灰霾的时间变化特征以及主要大气污染物与能见度的相关性。1997—2012年,灰霾天气占41.2%,发生天数没有明显变化,严重程度有所减缓。灰霾在冬季发生的天数最多,持续时间长,且容易发生重度的持续灰霾。夏季灰霾天数最少,程度最轻。PM10、PM2.5、SO2、NO2浓度随灰霾的加重而增加,其中PM2.5浓度增幅最大,O3浓度随灰霾的加重而降低。灰霾对能见度的影响大于降水天气对其的影响。灰霾天气下能见度受PM2.5的影响较大,非灰霾天气下,能见度主要受O3的影响。 相似文献
377.
酿酒酵母吸附Zn(Ⅱ)过程中阳离子(K+,Mg2+,Na+,Ca2+)的变化分析 总被引:2,自引:0,他引:2
研究了酿酒酵母无缓冲溶液体系吸附Zn(Ⅱ)的过程中各种阳离子的变化情况.研究结果表明,当Zn(Ⅱ)的初始浓度是0.08~0.8 mmol·L-1,酵母浓度约1 g·L-1,初始pH为5.65,反应38h内,酵母的Zn(Ⅱ)吸附量为74.8~654.8μmol·g-1,去除率达到76.4%~92.8%,pH值升高0.55~1.28.吸附过程中酵母首先快速释放大量K+,其次是Mg2+和Na+,Ca2+的释放量较少,数量级一般可分别达到几百、几十和几个μmol·g-1.以离子交换为基础计算的各阳离子释放量总和一般超过Zn(Ⅱ)的吸附量,证明酵母吸附Zn(Ⅱ)的机理之一是离子交换,但不唯一.无缓冲溶液体系酵母吸附Zn(Ⅱ)的过程中溶液pH值升高,H+被吸收,K+等阳离子释放,是生物体细胞的本质属性,与Zn(Ⅱ)是否存在无关,但是Zn(Ⅱ)可以促进阳离子的释放以及降低酵母对H+的吸收,也反映出Zn(Ⅱ)与H+之间可以竞争细胞表面吸附位.死酵母的吸附量低于未处理酵母,与阳离子交换能力关系不大,可能与细胞表面变形导致Zn(Ⅱ)吸附困难有关. 相似文献
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380.
Can Wu Gehui Wang Jiayuan Wang Jianjun Li Yanqin Ren Lu Zhang Cong Cao Jin Li Shuagshuang Ge Yuning Xie Xinpei Wang Guoyan Xue 《环境科学学报(英文版)》2018,30(9):179-187
Fireworks burning releases massive fine particles and gaseous pollutants, significantly deteriorating air quality during Chinese Lunar New Year(LNY) period. To investigate the impact of the fireworks burning on the atmospheric aerosol chemistry, 1-hr time resolution of PM_(2.5) samples in Xi'an during the winter of 2016 including the LNY were collected and detected for inorganic ions, acidity and liquid water content(LWC) of the fine aerosols. PM_(2.5) during the LNY was 167 ± 87 μg/m~3, two times higher than the China National Ambient Air Quality Standard(75 μg/m~3). K~+(28 wt.% of the total ion mass) was the most abundant ion in the LNY period, followed by SO_4~(2-)(25 wt.%) and Cl-(18 wt.%). In contrast, NO_3~-(34 wt.%) was the most abundant species in the haze periods(hourly PM32-2.5 75 μg/m), followed by SO_4(29.2 wt.%) and NH_4~+(16.3 wt.%), while SO_4~(2-)(35 wt.%) was the most abundant species in the clean periods(hourly PM_(2.5) 75 μg/m~3), followed by NO_3~-(23.1 wt.%) and NH_4~+(11 wt.%). Being different from the acidic nature in the non-LNY periods, aerosol in the LNY period presented an alkaline nature with a pH value of 7.8 ± 1.3. LWC during the LNY period showed a robust linear correlation with K_2SO_4 and KCl, suggesting that aerosol hygroscopicity was dominated by inorganic salts derived from fireworks burning. Analysis of correlations between the ratios of NO--3/SO_4~(2-) and NH_4~+/SO_4~(2-) indicated that heterogeneous reaction of HNO_3 with NH_3 was an important formation pathway of particulate nitrate and ammonium during the LNY period. 相似文献