亚热带小区域水平上土壤质量时空变化的定量化评价

亚热带小区域水平上土壤质量时空变化的定量化评价王效举，龚子同（中国科学院南京土壤研究所，南京２１０００８）ＱｕａｎｔｉｔａｔｉｖｅＥｖａｌｕａｔｉｏｎｏｆＳｏｉｌＱｕａｌｉｔｙＣｈａｎｇｅｓｉｎＴｉｍｅａｎｄＳｐａｃｅａｔａＳｍａｌｌＡｒｅａＬｅｖｅ...     

Theoretical study on the degradation reaction of octachlorinated dibenzo-p-dioxin with atomic oxygen O(3P) in dielectric barrier discharge reactor

Dielectric barrier discharges （DBD） have been used in the degradation of dioxins due to the large number of excimers and free radicals produced in discharge process. In this article, the density functional theory （DFT） is used to study the degradation mechanism of octachlorinated dibenzo-p-dioxin （OCDD） with the atomic oxygen O（3P） in DBD reactor. The reactants, intermediates, transition states and products are optimized at the MPWB1K/6- 31 ＋ G（d,p） level. The vibrational frequencies have been calculated at the same level. The reaction pathways and mechanisms are analyzed in detail. The effect of removing the chlorine atom on environment also has been discussed.     

Characterization of halogenated DBPs and identification of new DBPs trihalomethanols in chlorine dioxide treated drinking water with multiple extractions

Chlorine dioxide(ClO_2) is a widely used alternative disinfectant due to its high biocidal efficiency and low-level formation of trihalomethanes and haloacetic acids. A major portion of total organic halogen(TOX), a collective parameter for all halogenated DBPs, formed in ClO_2-treated drinking water is still unknown. A commonly used pretreatment method for analyzing halogenated DBPs in drinking water is one-time liquid–liquid extraction(LLE), which may lead to a substantial loss of DBPs prior to analysis. In this study, characterization and identification of polar halogenated DBPs in a ClO_2-treated drinking water sample were conducted by pretreating the sample with multiple extractions. Compared to one-time LLE, the combined four-time LLEs improved the recovery of TOX by 2.3 times. The developmental toxicity of the drinking water sample pretreated with the combined four-time LLEs was 1.67 times higher than that pretreated with one-time LLE.With the aid of ultra-performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry, a new group of polar halogenated DBPs, trihalomethanols,were detected in the drinking water sample pretreated with multiple extractions; two of them,trichloromethanol and bromodichloromethanol, were identified with synthesized standard compounds. Moreover, these trihalomethanols were found to be the transformation products of trihalomethanes formed during ClO_2disinfection. The results indicate that multiple LLEs can significantly improve extraction efficiencies of polar halogenated DBPs and is a better pretreatment method for characterizing and identifying new polar halogenated DBPs in drinking water.     

低温催化氧化中试装置对典型VOCs的治理效果分析

针对最新实施工业污染物排放标准,目前常规治理VOCs的工艺方法已不能达到新国标要求,中国石化安全工程研究院设计制造出针对炼化、码头和油库的油气回收的低温催化氧化中试装置,并利用此装置进行了几种典型VOCs气体的催化氧化实验,分析得到低温催化氧化中试装置对苯、二甲苯和汽油油气的治理效果理想,为实际工况下催化氧化VOCs工艺包设置提供数据支持,为低温催化氧化治理VOCs气体的工业推广应用打下了基础。     

双酚A暴露对斑马鱼胚胎期代谢作用的影响

运用基于GC/MS的代谢组学方法,以受精卵在双酚A(BPA)中暴露4d后的斑马鱼胚胎为对象,研究了其体内挥发性和半挥发性代谢组分变化.暴露浓度设定为0,0.5,1.5,4.5mg/L,包括US EPA假定的“安全水平”(1.5mg/L).结果表明,1.5mg/L BPA暴露能使斑马鱼体内花生四烯酸和胆固醇的相对百分含量极显著降低,饱和脂肪酸、氨基酸、葡萄糖和肌糖的相对百分含量显著升高.因此,1.5mg/L BPA能干扰斑马鱼胚胎期的正常代谢.     

淀粉接枝阳离子絮凝剂的制备及性能研究

主要利用化学方法对环氧氯丙烷和胺类进行阳离子改性获得阳离子醚化剂,然后与碱化后的淀粉接枝制得一种絮凝性能良好的有机高分子阳离子絮凝荆,并对所得产品作了絮凝性能实验。由实验得知该絮凝剂对悬浮细小颗粒有很好的去除效果,如高岭土溶液（1g／L）产生矾花时间较短,加入絮凝剂后搅拌3min左右即可产生明显絮体,且絮体较大,静置后透光率达90％以上。     

生物法治理污水处理场恶臭废气技术探讨

介绍了生物法治理污水处理场恶臭废气的工艺流程、基本原理,分析了对恶臭废气中有机污染物的去除效果,提出了需改进的问题。     

小城镇污水处理方案的模糊相似优先比决策模型

根据小城镇污水处理方案影响因素具有不完全性和不确定性的特点,建立了小城镇污水处理方案的模糊相似优先比决策模型,在该模型中,定义了模糊相似比,构造了污水处理方案影响因素的模糊相似优先关系,利用层次分析法确定了各影响因素的权重,从整体上找出了与理想方案最为相似的处理方案。实例分析表明,该模型决策结果合理、使用方便具有实用价值,为污水处理方案的决策分析提供参考。     

高盐矿区苦成水处理技术研究

针对新疆罗布泊钾盐矿区苦咸水高浊、高盐度和高硬度的水质特性,采用管道混凝＋多介质过滤＋精密过滤＋反渗透除盐的工艺进行处理。处理结果表明,该工艺对高浊、高盐度和高硬度苦咸水中的悬浮物、浊度和TDS均有良好的处理效果,矿区苦咸水经处理后TDS从8000mg／L降为30mg／L,二氧化硅增量小于20μg／L,处理后水质满足电厂发电机组补水要求,为严重缺水矿区高含盐劣质水利用提供了技术参考。     

Laboratory culture of the freshwater benthic gastropod Bellamya aeruginosa （Reeve） and its utility as a test species for sediment toxicity

This study aimed to develop original laboratory culture and sediment toxicity testing protocols for the freshwater gastropod Bellamya aeruginosa(Reeve),a new potential species for sediment toxicity testing.B.aeruginosa was successfully cultured with an effective culture system under proposed laboratory conditions.Optimal ad libitum feeding levels for larvae,juveniles,and adults were 2.0,6.0,and 16.0 mg fish food/(snail·day),respectively.Mean survival rates of juveniles were higher than 90%.The snails could be sexed at 9 weeks of age,and their generation time is approximately 4 months.Reproduction continued all year around;the mean fecundity was 0.55 newborn/(female·day).The utility of this species for bioassays was evaluated in both 10-day and 28-day case studies with artificial sediments.The 10-day LC50 of Cu for larvae was 480 μg/g dry weight(dw),and the lowest observed effects concentration of Cu for survival and growth of larvae was 195 μg/g dw.Survival and growth are reliable indicators of acute toxicity.Larvae accumulated more Cu than adults.B.aeruginosa exhibited a higher sensitivity to Cu exposure than standard test species(Hyalella azteca and Chironomus tentans).The 28-day test of sediment toxicity with adults showed that fecundity was a robust endpoint indicator of reproductive toxicity,and the biochemical endpoints of superoxide dismutase,catalase,and glutathione could be used as sensitive biomarkers for Cu-induced oxidative damage.B.aeruginosa can be therefore recommended as a candidate for the standardization of the freshwater sediment toxicity test protocol.