典型西南工业城市柳州市核心区大气污染物时空分布与气象因素研究

为研究柳州市核心区大气污染物浓度时空变化规律与气象因素之间的关系,统计分析了2018年全年研究区内6个自动监测站点PM_(2.5)、PM_(10)、SO_2、NO_2、O_3和CO的浓度监测数据和气象站气象数据,并对28次超标日污染物来源进行了解析.结果显示:①核心区颗粒污染物污染较为严重,且以PM_(2.5)为主的细颗粒污染物仍为柳州市主要的大气污染物;各污染物月均浓度季节差异显著,除NO_2外柳州大气污染物浓度下降明显,指示柳州市多项节能减排综合整治措施成效显著;PM_(2.5)、PM_(10)、CO受早晚高峰期影响,浓度日变化均呈双峰型;NO_2在不同季节峰型不同,作为O_3前体物其浓度日变化与O_3相反,呈现"早峰午谷"的变化趋势.②通过对污染物浓度插值发现,由于核心区主要工商业区位于西部且处于主导风向下风向,故PM_(2.5)和SO_2浓度西北高、东南低,PM_(10)、NO_2和CO浓度西南高、东北低;核心区东部的山区为O_3生成带来大量前体物,使O_3浓度东南高、西北低.③由于气候特征,核心区春、夏季主要气象因素均为降水量;秋季的主要气象因素是风速,风速与污染物的负相关关系表明了风的扩散效应;冬季大部分污染物与气象因素的相关性不显著,表明人为因素对污染物的影响大于气象因素;核心区大气污染物主要来源于局地排放和区域传输,且南北主导风向对大气污染影响最大.④HYSPLIT模型结果指示柳州超标日大气污染物主要来自于珠三角地区,且陆源颗粒物浓度普遍比海洋源高,来自南部的远距离输送气流颗粒物含量最低,表明远距离输送为影响颗粒物传播的主要原因.     

基于GIS的水环境非点源污染模型研究

非点源污染是水环境研究的重点和难点,利用模型对非点源污染进行研究是该项研究的重要内容之一.由于非点源污染具有广泛性、时空异质性和随机性的特点,用常规方法分析、评价、控制和管理有较大难度.随着地理信息系统(GIS)的发展以及非点源污染模型研究的不断深入,二者的结合已在该项研究中取得了一定成果.基于插件式GIS技术、RS技术、空间数据挖掘技术以及空间决策支持系统(SDSS)是非点源模型发展应用的趋势和方向.     

生物与化学表面活性剂对多氯联苯的协同增溶作用

采用室内序批试验比较研究了单一的生物/非离子化学表面活性剂(SAA)与生物-非离子混合表面活性剂对商业用多氯联苯(PCBs)Aroclor1242的增溶作用.结果表明,生物表面活性剂鼠李糖脂(RL)对Aroclor1242的增溶作用要高于三种非离子SAA,三种非离子SAA对Aroclor1242的增溶作用顺序为POE(6)＞POE(10)＞Brij35,与其亲水亲油平衡值(HLB)呈负相关;鼠李糖脂与非离子SAA对Aroclor1242的增溶存在协同效应,混合表面活性剂溶液中Aroclor1242的摩尔增溶比(MSR)、胶束相/水相间的分配系数(Kmc)均大于对应的单一表面活性剂,其协同增溶作用顺序为RL-Brij35＞RL-POE(10)＞RL-POE(6),协同增溶作用的大小与其中的非离子表面活性剂的HLB值呈正相关.     

Discovery of emerging organic pollutants in the atmosphere through an omics approach

● We review the framework of discovering emerging pollutants through an omics approach. ● High-resolution MS can digitalize atmospheric samples to full-component data. ● Chemical features and databases can help to translate untargeted data to compounds. ● Biological effect-directed untargeted analyses consider both existence and toxicity. Ambient air pollution, containing numerous known and hitherto unknown compounds, is a major risk factor for public health. The discovery of harmful components is the prerequisite for pollution control; however, this raises a great challenge on recognizing previously unknown species. Here we systematically review the analytical techniques on air pollution in the framework of an omics approach, with a brief introduction on sample preparation and analysis, and in more detail, compounds prioritization and identification. Through high-resolution mass spectrometry (HRMS, typically coupled with chromatography), the complicated environmental matrix can be digitalized into “full-component” data. A key step to discover emerging compounds is the prioritization of compounds from massive data. Chemical fingerprints, suspect lists and biological effects are the most vital untargeted strategies for comprehensively screening critical and hazardous substances. Afterward, compressed data of compounds can be identified at various confidence levels according to exact mass and the derived molecular formula, MS libraries, and authentic standards. Such an omics approach on full-component data provides a paradigm for discovering emerging air pollutants; nonetheless, new technological advancements of instruments and databases are warranted for further tracking the environmental behaviors, hence to evaluate the health risk of key pollutants.     

石英砂负载氧化铁吸附除磷的热动力学研究

通过吸附动力学实验及等温吸附实验,考察了在10～40℃的温度条件下石英砂负载氧化铁(IOCS)吸附磷的热动力学性质.结果表明:准二级反应动力学模型及Langmuir等温吸附模型可分别较好地描述IOCS对磷的吸附动力学及吸附等温线实验结果(R2≥0.98);吸附速率及吸附容量随温度的增加而增加.吸附速率k从0.0095增加到0.0173,吸附容量从0.06 mg/g增加到0.08 mg/g.根据标准吉布斯自由能变(△G0＜0)和标准反应焓变(△H0＞0)值判断,IOCS对磷的吸附是自发的、吸热的化学吸附反应.     

改性氧化铝微波诱导催化氧化处理高浓度苯酚废水的研究

采用微波诱导催化氧化技术,以改性氧化铝为催化剂,对高浓度模拟苯酚废水进行氧化处理。考察了微波功率、催化剂投加量、H202投加量、废水pH值和微波反应时间等因素对苯酚去除效果的影响。实验结果表明,处理30mL质量浓度为1 100mg/L的苯酚模拟废水,在微波功率500W,催化剂加入量1 g(液固比30∶1),30％双氧水...     

Perfluorinated compounds in the Pearl River and Yangtze River of China

A total of 14 perfluorinated compounds (PFCs) were quantified in river water samples collected from tributaries of the Pearl River (Guangzhou Province, south China) and the Yangtze River (central China). Among the PFCs analyzed, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were the two compounds with the highest concentrations. PFOS concentrations ranged from 0.90 to 99 ng/l and <0.01–14 ng/l in samples from the Pearl River and Yangtze River, respectively; whereas those for PFOA ranged from 0.85 to 13 ng/l and 2.0–260 ng/l. Lower concentrations were measured for perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctanesulfoamide (PFOSA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorononaoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA). Concentrations of several perfluorocarboxylic acids, including perfluorododecanoic acid (PFDoDA), perfluorotetradecanoic acid (PFTeDA), perfluorohexadecanoic acid (PFHxDA) and perfluorooctadecanoic acid (PFOcDA) were lower than the limits of quantification in all the samples analyzed. The highest concentrations of most PFCs were observed in water samples from the Yangtze River near Shanghai, the major industrial and financial centre in China. In addition, sampling locations in the lower reaches of the Yangtze River with a reduced flow rate might serve as a final sink for contaminants from the upstream river runoffs. Generally, PFOS was the dominant PFC found in samples from the Pearl River, while PFOA was the predominant PFC in water from the Yangtze River. Specifically, a considerable amount of PFBS (22.9–26.1% of total PFC analyzed) was measured in water collected near Nanjing, which indicates the presence of potential sources of PFBS in this part of China. Completely different PFC composition profiles were observed for samples from the Pearl River and the Yangtze River. This indicates the presence of dissimilar sources in these two regions.     

净化烹饪油污微生物菌种的选育

利用正交试验方法优化了净化烹饪油污菌种选育的环境和营养条件 ,即 :油 :2 0mL、NaNO3( 2g L) :4mL、KH2 PO4( 0 .5g L) :3mL、微量元素溶液 (CuSO4·5H2 O 0 .0 3g L ,ZnSO4·7H2 O 0 .1g L ,MnCl2 ·4H2 O 0 .0 5g L) :1mL和温度 3 7℃ ;而且得出氮源是影响菌体增长的最重要因素 ,温度是影响微生物降解的重要因素 ,而微量元素和磷源对菌种培育结果影响较小。在此优化条件下选育出了合适降解烹饪油污的c种子菌液 ,其每天可降解油 2 2mg L以上 ,并鉴定出主要的微生物是嗜水性气单孢菌 (Aeromonashydrophila 4AK4)、黄丝藻属 (Tribonema)和多甲藻属 (Peridinium)等菌体 ;分析了选育过程活性微生物、目标污染物和微生物的代谢产物三者之间的关系 ,发现所选微生物能利用油类物质作为碳源进行生长代谢     

颗粒污泥粒径的工程测定方法

厌氧反应器污泥粒径分布的测试方法目前主要有激光粒度分析、照相、沉降法和筛分法.快速方便的实用方法是筛分法,但筛分时需用缓冲剂,考察了分别用缓冲液和自来水作为冲洗介质的筛分结果.结果表明,作为现场应用自来水替代缓冲液是可行的,能够准确反映出污泥颗粒粒径变化的趋势,同时给出了试验测定方法和原则,确定了最佳污泥取样量为20 mL.     

Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition.