The distribution of molybdenum in the tissues of wild ducks

The Mo contents and the relations between Mo and Cu or Crcontents were investigated in the organs of Japanese wild ducks(spotbill duck, pintail, wigeon, scaup and tufted duck). Thehighest Mo content in kidney and liver of the dabbling duckswere more than 30 g g^-1 dry weight (g g^-1 d.wt.), though that of diving ducks were less than 11 gg^-1 d. wt. The contents were lower in the ducks migratingwithin Japan, Eurasia and North America than those in the birdsmigrating between Japan and Eurasia. The contents of liver inall species were more than 50 and less than 5 g g^-1 d.wt. for Cu and Cr, respectively. Significant correlations werefound between Mo and both elements in pintail and scaup, and Moand Cr in tufted duck. These results suggest that thecontamination of wild ducks reflects the reproductive area, andnot the collected area. Mo contents closely correlated with theCu and/or Cr contaminations.     

城市污水污泥发酵制园林营养土中微生物的变化分析

通过桶装发酵装置,进行城市污水污泥发酵制园林营养土过程中微生物的变化研究,测试不同好氧-厌氧交替组的发酵温度以及细菌、真菌、放线菌数量等的变化,探讨发酵温度与微生物变化的规律.结果表明,夏季不同发酵方式的发酵温度在50℃以上的持续时间均长于冬季,且夏季好氧-厌氧交替发酵的发酵温度在55℃以上的持续时间长于好氧发酵;冬季与夏季的好氧、好氧-厌氧交替发酵后,堆料中的粪大肠菌群数量均达到了《城镇污水处理厂污泥处置园林绿化用泥质》(CJ 248-2007)的卫生学指标要求;夏季好氧-厌氧交替发酵过程中,厌氧后发酵温度有所下降,好氧后发酵温度又有所回升;无论好氧还是好氧～厌氧交替发酵中,细菌均为优势种群,真菌、放线菌数量比细菌数量低2～6个数量级.     

煤矿复垦区土壤重金属分布特征与质量评价

为保证煤矿复垦区种植农作物的充填复垦土壤的生态安全,以淮南矿区煤矸石充填复垦地为研究对象,通过对研究区内Cd、Cr、Ni、Pb、Cu、Zn和Hg 7种重金属不同深度含量分析,总结其纵向分布特征,并将研究区土壤重金属含量与淮南市土壤背景值、《土壤环境质量标准》(GB 15618-1995)作比较,分析这7种重金属的污染程度.结果表明,这7种重金属都有不同程度的污染,其中土壤受Cd污染最严重,土壤中重金属垂直方向上无确定分布规律.总体而言,土壤重金属潜在生态风险属于强生态危害.从垂直方向来看,重金属潜在生态风险指数(RD随着深度的增加出现先下降后升高的趋势,其中40～60 cm深度的RI最大.重金属生态危害程度依次为Cd＞ Hg＞ Ni＞ Cu＞ Cr＞ Pb＞ Zn,其中Cd为矿区土壤中最主要的重金属污染生态风险因子.     

A novel approach for VOC source apportionment combining characteristic factor and pattern recognition technology in a Chinese industrial area

Volatile organic compound (VOC) emission control and source apportionment in small-scale industrial areas have become key topics of air pollution control in China. This study proposed a novel characteristic factor and pattern recognition (CF-PR) model for VOC source apportionment based on the similarity of characteristic factors between sources and receptors. A simulation was carried out in a typical industrial area with the CF-PR model involving simulated receptor samples. Refined and accurate source profiles were constructed through in situ sampling and analysis, covering rubber, chemicals, coating, electronics, plastics, printing, incubation and medical treatment industries. Characteristic factors of n-undecane, styrene, o-xylene and propane were identified. The source apportionment simulation results indicated that the predicted contribution rate was basically consistent with the real contribution rate. Compared to traditional receptor models, this method achieves notable advantages in terms of refinement and timeliness at similar accuracy, which is more suitable for VOC source identification and apportionment in small-scale industrial areas.     

再生条件对钾基CO_2吸附剂吸附性能的影响

通过固定床实验研究了再生条件对钾基CO2吸附剂吸附性能的影响。深入分析了再生温度和气氛对吸附穿透时间和饱和吸附量的影响。研究发现,当再生温度为200℃,N2气氛下再生时效果最佳,在此条件下再生后钾基CO2吸附剂循环性能良好,10次循环后仍然能有很好的吸附效果;再生气氛中有H2O或CO2时会影响再生反应的进行,不利于吸附剂的再生。     

耐盐苯酚降解菌Staphylococcus sp.的分离及降解特性

从巴丹吉林沙漠盐湖表层沉积物中筛选到一株高效耐盐苯酚降解菌CL.测定了菌株CL的生理生化指标、16S rRNA基因序列,通过动力学模型探究了该菌株的生长和苯酚降解特性,同时考察了固定化对其耐受及降解苯酚能力的影响.结果表明,菌株CL属于葡萄球菌属(Staphylococcus sp.),在温度30℃、pH 7.0—8.0、盐度0—10%和苯酚浓度100—200 mg·L~(-1)条件下,该菌株能高效降解苯酚,其降解率均在85%以上.菌株CL对不同浓度苯酚的降解符合Haldane模型,其最大比降解速率和抑制常数分别为0.32 h~(-1)和351.70 mg·L~(-1),同时该菌株在不同盐度下对苯酚的降解符合Ghose and Tyagi模型.固定化可以明显增加菌株CL对苯酚的降解和耐受能力.菌株CL在高盐环境下能够高效降解苯酚,具有生物处理高盐含酚废水的潜力.     

钴铜铁三元类水滑石材料催化过硫酸氢钾复合盐降解苯酚

采用共沉淀法制备过渡金属钴、铜、铁组成的钴铜铁三元类水滑石材料(CoCuFe-LDH),用于催化过硫酸氢钾复合盐(PMS)降解水中苯酚,并考察了初始pH、CoCuFe-LDH催化剂投加量、PMS用量对苯酚降解效率的影响。实验结果表明:CoCuFeLDH对PMS的催化活性较高;在pH为中性,催化剂为0.20g/L,PMS为2.5mmol/L,苯酚为50mg/L的条件下处理60min,苯酚的去除率可达96%;当催化剂投加量分别为0.05、0.10、0.15g/L,反应40min时,苯酚的去除率分别为76%、82%和91%。自由基猝灭实验表明,CoCuFe-LDH/PMS催化体系中存在硫酸根自由基和羟基自由基,但硫酸根自由基为主要活性自由基。     

An integrated chemical mass balance and source emission inventory model for the source apportionment of PM2.5 in typical coastal areas

The source apportionment of PM_2.5 is essential for pollution prevention. In view of the weaknesses of individual models, we proposed an integrated chemical mass balance-source emission inventory (CMB-SEI) model to acquire more accurate results. First, the SEI of secondary component precursors (SO₂, NO_x, NH₃, and VOCs) was compiled to acquire the emission ratios of these sources for the precursors. Then, a regular CMB simulation was executed to obtain the contributions of primary particle sources and secondary components (SO₄^2?, NO₃^-, NH₄⁺, and SOC). Afterwards, the contributions of secondary components were apportioned into primary sources according to the source emission ratios. The final source apportionment results combined the contributions of primary sources by CMB and SEI. This integrated approach was carried out via a case study of three coastal cities (Zhoushan, Taizhou, and Wenzhou; abbreviated WZ, TZ, and ZS) in Zhejiang Province, China. The regular CMB simulation results showed that PM_2.5 pollution was mainly affected by secondary components and mobile sources. The SEI results indicated that electricity, industrial production and mobile sources were the largest contributors to the emission of PM_2.5 gaseous precursors. The simulation results of the CMB-SEI model showed that PM_2.5 pollution in the coastal areas of Zhejiang Province presented complex pollution characteristics dominated by mobile sources, electricity production sources and industrial production sources. Compared to the results of the CMB and SEI models alone, the CMB-SEI model completely apportioned PM_2.5 to primary sources and simultaneously made the results more accurate and reliable in accordance with local industrial characteristics.     

查干湖汇水区面源污染风险识别及管控

面源污染是我国流域面临的主要水环境问题,为了识别面源污染高风险区和潜在风险路径,实现流域水环境保护,以查干湖水质目标为约束条件,构建4类关键“源”景观.选取高程、坡度、土地利用类型、污染强度、距居民点距离、距公路距离、距铁路距离、距水体距离等8个评价因子构建阻力面,对查干湖汇水区面源污染风险区和风险路径进行识别,提出管控分区和治理措施.结果表明:①查干湖汇水区关键“源”景观有4类,分别为面源污染单位面积高负荷区、坡度>3°区域、污染传输通道和临湖区域,面积共126.33 km2.②查干湖汇水区面源污染高风险区即面源污染重点管控区,占汇水区总面积的27.10%,主要位于乾安灌区有字泡区域、查干湖及周边泡沼沿岸.区内现有耕地不再增加,同时对坡度较大的区域退耕还湿、退耕还草,并设置污染降解设施.③查干湖汇水区面源污染较高风险区即面源污染一般管控区,占汇水区总面积的20.23%.该区鼓励开展有机农业,发展生态旅游.④查干湖北岸和东南岸、库里泡周边设置一定宽度的植被缓冲带,汇水区设置生态降解渠道333.41 km,生态湿地节点9个.研究显示,污染排放强度是查干湖汇水区面源污染风险的主要威胁因素,需要重点加强查干湖汇水区乾安灌区有字泡、湖区北岸及东南岸的面源污染管控.