大连地区夏季非甲烷烃(NMHC)特征及其来源解析

非甲烷烃(NMHC)是臭氧的重要前体物之一,对臭氧的生成起着决定性的作用.为研究大连地区大气中NMHC的特征和来源,利用在线NMHC监测仪测定大连地区2014年7月和8月的NMHC组成、日变化并计算该地区的臭氧生成潜势,利用PCA受体模型初步估算大连地区NMHC来源.结果表明,大连地区总NMHC年平均浓度(体积分数)分别为80.7×10-9±62×10-9,其中烷烃所占比例最高,占NMHC总浓度的64%,其次是烯烃19%,芳香烃16%,乙炔1%.正癸烷、乙烯、正辛烷是大连地区NMHC中浓度最高的3种物质,部分物种浓度呈现明显的日变化特征.臭氧生成潜势(OFP)结果显示,大连地区芳香烃对该地区OFP的贡献最大,乙烯、间-乙基甲苯和对-乙基甲苯是对该地区OFP贡献最大的物质.利用主成分分析VOCs物种,提取出6个因子,分别归纳为溶剂使用、液化石油气(LPG)、汽车尾气、植物排放、石化炼制加工和老化气团传输.     

油库、加油站作业场所中非甲烷总烃的测定

介绍了油库、加油站作业场所中非甲烷总烃分布的特点,对现有非甲烷总烃测定方法进行了分析,提出了研制便携式带氢火焰离子检测器的气相色谱法作为现场检测油库、加油站作业场所中非甲烷总烃测定的建议。     

土地处理池塘污水影响因素的实验研究

通过户外动态土柱模拟实验,研究了淹水时间、土壤厚度、土壤粒径和淹水深度对池塘污水处理效果的影响。实验结果表明:连续淹水超过4～5d,COD去除率明显下降;相同进水条件下,土层厚度在120cm处,COD去除率达到80%以上;土壤粒径<0.1mm时,COD去除率达到90%;在土层厚度120cm处,淹水深度为60cm时,COD去除率仅40%。     

Biodegradation of polycyclic aromatic hydrocarbons in sediments from the Daliao River watershed, China

The Daliao River, as an important water system in Northeast China, was reported to be heavily polluted by polycyclic aromatic hydrocarbons (PAHs). Aerobic biodegradations of four selected PAHs (naphthalene, phenanthrene, fluorene and anthracene) alone or in their mixture in river sediments from the Daliao River water systems were studied in microcosm systems. E ects of additional carbon source, inorganic nitrogen and phosphorus, temperature variation on PAHs degradation were also investigated. Results showed that the degradation of phenanthrene in water alone system was faster than that in water-sediment combined system. Degradation of phenanthrene in sediment was enhanced by adding yeast extract and ammonium, but retarded by adding sodium acetate and not significantly influenced by adding phosphate. Although PAHs could also be biodegraded in sediment under low temperature (5°C), much lower degradation rate was observed. Sediments from the three main streams of the Daliao River water system (the Hun River, the Taizi River and the Daliao River) demonstrated di erent degradation capacities and patterns to four PAHs. Average removal rates (15 or 19 d) of naphthalene, phenanthrene, fluorene and anthracene by sediment were in the range of 0.062–0.087, 0.005–0.066, 0.008– 0.016 and 0–0.059 mg/(L d), respectively. As a result, naphthalene was most easily degraded compound, anthracene was the hardest one. In multiple PAHs systems, the interactions between PAHs influenced each PAH biodegradation.     

堆制技术对土壤中石油烃的降解研究

土壤的石油污染已成为黄河三角洲地区严重的环境问题。研究利用静态堆制技术比较了不同辅料添加量对原油污染土壤中石油烃降解效率的影响,分析了堆制过程中微生物数量和活性的差异,建立了最佳堆制配比及堆制条件。试验结果表明,污染土壤与辅料的体积比为1∶3时的处理效果最好。在堆制第3天至第18天,堆体温度维持在40～50℃、pH值7.5左右、C∶N约为15∶1,此时最适于石油烃降解菌的生长,土壤中石油烃的降解速率最快。60天后,土壤中总石油烃的降解率可达80%,远高于没有添加辅料及营养的对照堆体的降解率(约为40%)。     

抚顺市非甲烷烃的时空分布规律

本文采用分别测定以氮气和空气为底气的同一浓度的甲烷标准气体的响应值,两者之差值即为空气中氧对总烃测定的空白值,代替传统的用除烃净化空气装置制备净化空气测定空白值的方法,并将该法应用于抚顺市非甲烷烃的含量测定,取得较理想结果。同时研究了抚顺市非甲烷烃的时空分布规律。     

经济快速发展区六氯丁二烯的来源与分布特征

为解析长三角、京津冀和珠三角地区六氯丁二烯（HCBD）来源及分布特征,基于三大区域氯代烃生产水平及废水排放情况对三大区域HCBD排放来源及其在水体和土壤中的分布情况开展研究.结果表明,三氯乙烯（TCE）和四氯乙烯（PCE）生产副产物以及污水处理厂污水污泥排放成为三大区域HCBD主要来源.2018年三大区域中来自TCE和PCE生产副产物的HCBD总排放量为498.46 t,其中来自TCE生产副产物的占比为66.9%.三大区域工业及生活污水处理厂HCBD排放量分别为628.9 kg和254.6 kg.长三角地区氯代烃生产及污水处理厂HCBD排放量显著较高,分别为497.8 t和648 kg,而京津冀地区两类源排放量为0.37 t和125 kg,珠三角地区为0.29 t和110.3 kg.长三角、京津冀和珠三角地区自然水体中HCBD平均质量浓度分别为0.35、0.25和0.64 μg·L^-1,饮用水中HCBD平均质量浓度为0.16、0.09和0.04 μg·L^-1.城市饮用水中HCBD的整体水平较低.工业土壤中HCBD含量显著高于农田土壤,含量分别为9.3~24.6 ng·g^-1和0.13~2.67 ng·g^-1.与水体中HCBD污染情况相同,长三角地区土壤中HCBD污染最为严重,这与长三角地区HCBD排放量显著高于京津冀和珠三角地区相关,亟需引起重视.     

Impacts of n-alkane concentration on soil bacterial community structure and alkane monooxygenase genes abundance during bioremediation processes

Petroleum hydrocarbons, mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), are considered as priority pollutants and biohazards in the environment, eventually affecting the ecosystem and human health. Though many previous studies have investigated the change of bacterial community and alkane degraders during the degradation of petroleum hydrocarbons, there is still lack of understanding on the impacts of soil alkane contamination level. In the present study, microcosms with different n-alkane contamination (1%, 3% and 5%) were set up and our results indicated a complete alkane degradation after 30 and 50 days in 1%- and 3%-alkane treatments, respectively. In all the treatments, alkanes with medium-chain length (C₁₁-C₁₄) were preferentially degraded by soil microbes, followed by C₂₇-alkane in 3% and 5% treatments. Alkane contamination level slightly altered soil bacterial community, and the main change was the presence and abundance of dominant alkane degraders. Thermogemmatisporaceae, Gemmataceae and Thermodesulfovibrionaceae were highly related to the degradation of C₁₄- and C₂₇-alkanes in 5% treatment, but linked to alkanes with medium-chain (C₁₁-C₁₈) in 1% treatment and C₂₁-alkane in 3% treatment, respectively. Additionally, we compared the abundance of three alkane-monooxygenase genes, e.g., alk_A, alk_P and alk_R. The abundance of alk_R gene was highest in soils, and alk_P gene was more correlated with alkane degradation efficiency, especially in 5% treatment. Our results suggested that alkane contamination level showed non-negligible effects on soil bacterial communities to some extents, and particularly shaped alkane degraders and degrading genes significantly. This study provides a better understanding on the response of alkane degraders and bacterial communities to soil alkane concentrations, which affects their biodegradation process.

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Simple and rapid determination of dioxin in fish and sea food using a highly sensitive reporter cell line, CBG 2.8D

Food, especially animal origin food is the main source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and dioxin-like polychlorinated biphenyls (dl-PCBs) for human exposure. So, a simple, rapid and cheap bioassay method is needed for determination of dioxins in food samples. In this study, we used a new highly sensitive reporter cell line to determine the concentration of dioxins in 33 fish and seafood samples. The samples were extracted by shaking with water/isopropanol (1:1 v/v) and hexane and cleaned-up by a multi layered silica gel column and an alumina column, then analyzed using CBG 2.8D cell line. We compared the results obtained from the CBG 2.8D cell assay to those obtained from conventional High-Resolution Gas Chromatography–High Resolution Mass Spectrometry (HRGC–HRMS) analysis. Good correlations were observed between these two methods (r²=0.93). While the slope of regression line was 1.76, the bioanalytical equivalent (BEQ) values were 1.76 folds higher than WHO-TEQ values and the conversion coefficient was 0.568 (the reciprocal of 1.76). In conclusion, CBG 2.8D cell assay was an applicable method to determine dioxins levels in fish and sea food samples.     

磷石膏改善苏打碱土理化性质效果分析

分析了磷石膏对苏打碱土团聚体稳定性、饱和导水率和盐分淋洗效果的影响.结果表明:水稳定大团聚体质量分数和饱和导水率均随磷石膏施用量的逐渐增加而不断提高,磷石膏施用量达到100%GR时,水稳性大团聚体质量分数从对照的0.03%增加到33.31%,饱和导水率从对照的0.13 mm·d~(-1)提高到3.14 mm·d~(-1);出流液电导率和pH均随磷石膏施用量的增加而降低,磷石膏施用量达到100%GR时,出流液电导率和pH分别从对照的8.85 mS·cm~(-1)和10.26降低到3.46mS·cm~(-1)和9.83.因此,磷石膏对苏打碱土理化性质的改良效果十分显著.