Mercury speciation and mobility in mine wastes from mercury mines in China

Mercury (Hg) speciation and mobility were determined in calcines and waste rocks collected from 9 Hg mines in China. Total Hg (THg) concentrations in the mine wastes varied widely in different Hg mines (with a range of 0.369 to 2,620 mg kg^?1). Cinnabar is the dominant form of Hg in the mine wastes. However, Hg²⁺ and Hg⁰ concentrations in the calcines were significantly higher than these in the waste rocks, which suggested the retorting can produce large amounts of by-product Hg compounds. The THg and Hg⁰ concentrations in certain mine wastes exceeded soil guidelines recommended by US Environmental Protection Agency; while total soluble Hg concentrations of leachates in certain mine wastes exceeded National Surface Water Quality Standard of China. Mine wastes are important Hg pollution sources to the aquatic ecosystem and atmosphere.     

2株油烟降解优势菌株的筛选及性能研究

通过以油烟冷凝液为惟一碳源的选择培养基初筛,从长期受到油烟严重污染的土壤中筛选出具有降解油烟污染物能力的优势菌株XJ01、XJ03。研究了其最佳生长条件及降解性能,并对其进行了生理生化特征及分子生物学鉴定。研究表明,XJ01、XJ03最佳生长温度分别为35℃、30℃,最佳生长pH均为7,摇床转速均为120r／min,最佳降解时间分别为48h和36h;在最佳降解条件下,xJ01、XJ03总降解量分别达4．47113g／L和4．18ing／L,降解过程中,降解液pH值持续下降,生物量先增加后下降。经分子生物学鉴定,菌株XJ01、XJ03分别与铜绿假单胞菌群（Pseudomonasaeruginosagroup）和克雷伯氏菌属（Klebsiellasp．）同源性最高均达到100％。     

Occurrence and fate of PPCPs and correlations with water quality parameters in urban riverine waters of the Pearl River Delta, South China

The occurrence and fate of eight PPCPs was studied in river waters from upstream to downstream of the three rivers in the Pearl River Delta, China. The correlations of PPCP levels and water quality parameters were also investigated. The analytes of the highest concentrations were caffeine, acetaminophen, and ciprofloxacin. Carbamazepine and erythromycin-H₂O were detected at the lowest concentrations. The highest concentrations of PPCPs were found in the Shijing River, with 865 ng/L caffeine, 339 ng/L acetaminophen, and 304 ng/L ciprofloxacin. In general, the levels of PPCPs in the Zhujiang River were higher at sites where the metropolitan city Guangzhou is located and decreased from the epicenter along the river. Low levels of PPCPs were generally found in the Beijiang River. Positive correlations were found between PPCP levels, total nitrogen, ammonium nitrogen, and cumulative fluorescence excitation-emission matrix (EEM) volume. Among the four PPCPs evaluated (caffeine, acetaminophen, ciprofloxacin, and sulfamethoxazole), caffeine had the best correlations with the correlation coefficients ranging from 0.62 to 0.98. The prediction of PPCP concentrations at specified locations can be substantially simplified.     

不同工艺对含高浓度腐殖酸地下水处理的可行性

针对内蒙古农村地区高腐殖酸地下水的处理问题,分别对（pH调节）-PAC强化混凝、高锰酸钾预氧化／混凝、活性炭吸附／混凝、Fenton氧化等技术处理的可行性进行了研究,同时利用三维荧光和高效体积排阻色谱分析处理前后水中有机物的组成变化特征。有机分析结果显示,水中的有机物为腐殖酸类物质,分子量分别为1600和3500,腐殖酸类物质为水中色度的主要贡献者。原水PAC强化混凝、高锰酸钾预氧化／PAC混凝对有机物的去除效果不佳,处理前后水样DOC浓度无明显变化,而pH调节．PAC强化混凝、微米活性炭吸附和Fenton氧化均能有效去除有机物。将原水pH调节至6．5,经300mg／LPAC混凝后出水DOC降至5．99mg／L。活性炭投加量为0．6g／L时,DOC降至7．6mg／L,然后采用60mg／LPAC混凝出去高度分散而不易沉降的小颗粒活性炭。此外,当反应初始pH值为3,过氧化氢投加量为0．5％（v／v）,亚铁和双氧水摩尔比为0．05时,出水DOC降至5．6mg／L,氧化后有小分子有机物生成。     

不同密度沉水植物腐解过程中水体DOM变化特征

选取白洋淀淀区的泥、水以及晒干的优势沉水植物金鱼藻、轮藻为研究对象,设置6个密度梯度模拟实验,分别于实验进行的50 d和100 d采集水样,运用紫外和荧光光谱技术研究沉水植物腐解阶段水体中溶解性有机质(DOM)的变化。结果显示,同步荧光光谱中,类蛋白峰荧光强度的变化不具规律性,类腐殖质峰荧光强度随密度的增加呈上升趋势,I2/I1的值随着密度的增加或时间的推移均逐渐增大;三维荧光光谱中,随着密度的增加,类富里酸荧光峰A和C的强度逐渐增加,而类色氨酸荧光峰T1的强度变化不大,腐解植物的密度大于3 kg/m3时各组均产生了类海洋腐殖质荧光峰B且强度随密度的增加逐渐增强,C峰的强度与水样中的COD和TP呈显著正相关;紫外光谱测定中,A253/A203的值随着密度的增加或时间的推移而逐渐增大,水体中的芳香族化合物也增多。     

磷酸钙盐结晶除磷工艺性能研究

研究了主要工艺条件pH和Ca/P对磷酸钙盐结晶除磷工艺性能的影响。通过分批实验,建立了磷去除率与pH之间的指数函数关系以及磷去除率与Ca/P之间的对数函数关系。连续运试表明,在pH=9.0、Ca/P=2的条件下,磷酸钙盐结晶除磷反应器的容积负荷为1.10 kg P/(m3.d),磷去除率为51%。灵敏度分析表明,pH对磷去除率的影响大于Ca/P,将Ca/P提高至6,容积负荷提高至1.60 kg P/(m3.d),磷去除率提高至74.3%;将pH提高至10.0,容积负荷提高至1.80 kg P/(m3.d),磷去除率提高至83.5%。工艺操作上可选pH作为优先控制对象。     

不同纳米修复剂对污染土壤中胡萝卜吸收、转运Cd的影响

通过盆栽实验研究不同纳米修复剂(羟基磷灰石HAP、赤泥RM、Fe3O4、胡敏酸-Fe3O4)对2种不同污染土壤Cd吸收、转运的影响。结果表明,上述纳米修复剂均可显著增加胡萝卜植株生物量,显著提高植株Cd胁迫的耐受指数;不同土壤施用不同纳米修复剂均显著降低胡萝卜植株Cd的含量,并且随着修复剂施加浓度的增加而显著降低;与对照相比,植株茎叶Cd含量最大降低达78.8%,根中Cd的含量最大降低67.8%;添加不同修复剂能不同程度地降低了土壤中Cd的转运系数和富集系数,这可能与施用不同纳米修复剂促进了土壤中非残留态Cd向残留态Cd的转化有关,总体而言,不同纳米型修复剂对降低Cd的有效性顺序为:RM～HAP>胡敏酸-Fe3O4>Fe3O4。     

SBR处理高浓度养猪废水工艺条件

以养猪场废水作为研究对象,采用序列间歇式活性污泥法SBR,通过实验研究了供气量、pH、排泥量、原水稀释倍数、水力停留时间（HRT）对SBR出水水质的影响。结果表明,供气量为375 L/（min·m³）、pH为8.0,并添加排泥100 mL的操作,可使SBR处理效果明显提高,COD、磷和凯氏氮去除率最高分别可达96.37%、94.14%、99.38%。逐步降低进水稀释倍数有利于培养出处理高浓度有机养猪废水的活性污泥,可将平均COD、磷和凯氏氮含量高达9 161.24、33.41和1 502.77 mg/L的养猪废水处理至出水的490.11、5.35和17.84 mg/L。降低HRT对SBR去除率影响不大。     

Characterization of Urea Encapsulated by Biodegradable Starch-PVA-Glycerol

The influence of the blending ratio of biodegradable starch/polyvinyl alcohol (PVA)/glycerol in encapsulating urea has been investigated. It is found that water absorption capacity increased approximately 135 % as the amounts of starch, PVA and glycerol in the composite film increase. Therefore, the swell ability of the composite film is increased and the urea is released from the composite film in the wet environment. The FTIR shows that the urea had been encapsulated successfully in the composite films. Moreover, the soil burial biodegradation results indicated that the biodegradability of the starch/PVA/glycerol/urea composite film strongly depended on the PVA proportion in the composite film matrix. The DSC results show that the higher the amount of PVA in the composite film, the less change of the melting enthalpy value. The crystalline region of PVA remains after biodegradation.     

Effects of submerged macrophytes on the abundance and community composition of ammonia-oxidizing prokaryotes in a eutrophic lake

Abundances and community compositions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in unvegetated sediment and the rhizosphere sediments of three submerged macrophytes (Ceratophyllum demersum, Vallisneria spinulosa, and Potamogeton crispus) were investigated in a large, eutrophic freshwater lake, Lake Taihu. Abundances of archaeal ammonia monooxygenase alpha-subunit (amoA) gene (from 6.56?×?10⁶ copies to 1.06?×?10⁷ copies per gram of dry sediment) were higher than those of bacterial amoA (from 6.13?×?10⁵ to 3.21?×?10⁶ copies per gram of dry sediment) in all samples. Submerged macrophytes exhibited no significant effect on the abundance and diversity of archaeal amoA gene. C. demersum and V. spinulosa increased the abundance and diversity of bacterial amoA gene in their rhizosphere sediment. However, the diversity of bacterial amoA gene in the rhizosphere sediments of P. crispus was decreased. The data obtained in this study would be helpful to elucidate the roles of submerged macrophytes involved in the nitrogen cycling of eutrophic lake ecosystems.