海洋环境地球化学——Ⅳ.胶州湾娄山河口海域铬迁移转化规律研究

本文对排放入胶州湾中铬的主要污染源——娄山河河口海域及上游工业废水中铬的迁移形态特征及其转化;废水及河口海域海水中六价铬向三价铬的转变及其速率以及河口海域海水中三价铬向底质的迁移及其影响因素等地球化学过程进行了现场调查和室内模拟实验。实验结果进一步证实了胶州湾娄山河口及沿岸海域中铬的可能的迁移机制为Cr_水~(VI)→Cr_水~(Ⅲ)→Cr_水~(悬)→Cr_(底质~(酸溶)→Cr_(底质)~总,并为这一过程作了定量估算,提出了胶州湾娄山河口海域铬的迁移模式图。     

Occurrence of antibiotic resistance genes and bacterial pathogens in water and sediment in urban recreational water

The emergence and prevalence of antibiotic resistance genes(ARGs) and pathogens in the environment are serious global health concern. However, information about the occurrence of ARGs and pathogens in recreational water is still limited. Accordingly, we investigated the occurrence of six ARGs and human pathogens in three recreational lakes, and the correlations between ARGs and one mobile genetic element(intI1) were analyzed. The quantitative PCR results showed that the concentration of ARGs ranged from 4.58 × 10~0 to 5.0 × 10~5 copies/mL in water and from 5.78 × 10~3 to 5.89 × 10~8 copies/g dry weight(dw)in sediment. Sul1 exhibited the highest level among the five quantifiable ARGs. The concentrations of sul1, bla_(-TEM), and tetX exhibited significant positive correlations with intI1(p 0.05), indicating that intI1 may be involved in their proliferation. The detection frequencies of ARGs ranged from 75%–10~0%, indicating the prevalence of these risks in this region. The concentration of Escherichia coli, Aeromonas spp., Mycobacterium avium,Pseudomonas aeruginosa, and Salmonella enterica ranged from 10~3 to 10~5 copies/10~0 mL in water and 10~4–10~6 copies/g dw in sediment. In total, 25% of the samples harbored all pathogen genes, indicating the prevalence of these pathogens in recreational lakes.Furthermore, the next-generation sequencing results showed that 68 genera of pathogens were present, among which Aeromonas, Mycobacterium, and Pseudomonas were the dominant ones in this region, posing a considerable potential health risk to public health. Overall, the widespread distribution of ARGs and pathogens underscores the need to better monitor and mitigate their propagation in recreational lakes and the associated risks to human health.     

牡丹江水环境非点源污染控制及其研究

牡丹江地区开展非点源污染研究的最终目的是采取有效措施控制和减少污染.控制和减少非点源污染的具体方法有两个:一个是制定相应的法律、法规.另一个是采取适当的经济手段.对非点源污染控制的实施有三方面建议:一是加强非点源的调查和监测.二是加强非点源污染控制管理政策的理论研究.三是政策实施前要对其进行经济、技术、制度上的可行性论证评估.     

Molecular hologram derived quantitative structure-property relationships to predict physico-chemical properties of polychlorinated biphenyls

Polychlorinated biphenyls (PCBs) congeners with various degrees of chlorination and substitution patterns are among the most widespread and persistent man-made organic pollutants. They are toxic, lipophilic and tend to be bioaccumulated. The knowledge of the physico-chemical properties is very useful to explain the environmental behavior of PCBs and to perform an exposure assessment. In this paper, we have used a new molecular representation, the molecular hologram, to generate quantitative structure-property relationship models to predict the physico-chemical properties of biphenyl and all of its chlorinated congeners. The investigated properties include 1-octanol/water partition coefficient (logK(ow)), aqueous solubility (-logS(w)), aqueous activity coefficient (-logY(w)), Total molecular surface area, Henry's law constant (logH). The results show that this new quantitative structure-activity relationship approach presents highly predictive models for important physico-chemical properties of PCBs.     

类-Fenton体系对水中17β-雌二醇的光降解

以250W照明金属卤化物灯为光源研究了水中17β-雌二醇（E2）在类-Fenton体系中的光降解。结果表明，Fe（Ⅲ）／H2O2体系能有效地光降解E2。pH3～6范围内，E2光降解率及反应初始速率随酸度的增大而增大；H2O2初始浓度越大，E2降解率及反应初始速率越大；E2初始浓度越低，E2降解率越高，反应初始速率越低。     

Characteristics of and Human Influences on Nitrogen Contamination in Yellow River System, China

Nitrogen (N) contamination in the Yellow River mainstream and its tributaries was studied using data from 1960 to 2000 from 312 monitoring sites in the Yellow River system. Data showed that N concentrations in the Yellow River have increased since 1960, especially after 1990. N concentrations in the Yellow River mainstream increased from the upper reaches (less than 1.0 mg L(-1) for TN and less than 0.10 mg L(-1) for NH4(+)-N) to lower reaches (higher than 4-5 mg L(-1) for TN and higher than 1.0 mg L(-1) for NH4(+)-N). However, the highest N contaminations (50-250 mg L(-1) for TN and 10-20 mg L(-1) for NH4(+)-N) was found in some tributaries, which was attributed as an effect of industrial wastewater and municipal sewage. Nitrogen concentrations from several monitoring sites were positively correlated with several regional socio-economic indices, such as population density, fertilization rates, livestock, industrial input and GDP. Depending on location, seasonal N concentrations contrasted among watersheds. Monitoring stations located in rural and agricultural areas showed higher N concentrations during the flood season while those located in areas with urban and industrial centers showed higher N concentration during the dry season. Mainstream flow and N concentrations showed a strong inverse relationship; with higher N concentrations as the river flow declined. Intensive water extraction for agricultural irrigation and increasing N input to the river from fertilized agricultural fields could explain the increasing N concentrations during extensive droughts.     

新型循环流化床硝化-反硝化启动试验研究

利用新型循环流化床进行清水实验及硝化、反硝化启动试验研究,考察了系统对有机物和氮的去除效果,并分析了曝气量对系统启动的影响.结果表明,将输送床和传统流化床工艺进行有机结合,技术上可行,可以在系统内不同区建立缺氧、好氧条件,通过硝化和反硝化作用完成脱氮.     

制服CO2排放的新探索

介绍了全球ＣＯ２排放的概况，反映了世界各国对温室效应所致的全球性气温上升极为关注，在这样的背景下，科学家对ＣＯ２排放的收集方法，包括生物吸收和化工利用等方法，做了许多有效的探索和试验，有的已接近工业实验阶段，如挪威石油界的见解，能源界对ＣＯ２排放更为关注，正在对各种矿物发电方式，结合环保意识，进行深入的方案性比较，并提出初步倾向性的意见，如荷兰科研界的见解。     

长江武汉段水体中20种元素的赋存状态及其环境化学特征的研究

本文研究了20种元素在长江武汉段水体中的含量水平,分配特征及其影响因素,对底质粒经,物质组份,元素含量,水力条件,河床状况及悬浮物之间的相互关系作了较深入探讨,认为江段悬浮物及底质主要由上游水土流失形成,因而各元素量基本上是地球化学量。根据形态研究结果,提出了各元素潜在活性序列,指出如水体环境条件特别是 pH 变化可能严重影响水质状况。     

TiO2光催化降解脂肪烃类反应机制的探析

在半导体TiO2水悬浮体系中，对脂肪烃类的光催化降解反应机制进行了探讨。研究结果表明首先产生·OH和·OOH这两种活性物质，它们进攻脂肪烃类形成羟基化的中间体，然后进一步降解为醛、羧酸，最后生成CO2和H2O。