缺氧－好氧生物膜法脱氮技术的研究

为了防止氮污染对水体造成的危害,我国对氨氮排放实行严格的控制。采用缺氧－好氧淹没式生物膜脱氮方法研究其处理效果与工艺参数,并着重研究氮负荷和碳源对硝化、反硝化的影响;微生物在膜上的分布特性及其对底质变化的影响。研究结果表明：缺氧段（A段）停留时间为7.3h,好氧段（0段）为15.7h好氧段容积负荷：COD0.36kg/m³·d,NH₃－N0.35kg/m³·d;缺氧段硝态氮负荷0.65kg/m³·d,COD负荷1.7kg/m³·d。这一水处理技术工艺稳定,NH₃－N与NO_x－N的去除率均在90％以上,而且生物活性强,分布较均匀,是目前控制氮污染的有效方法。     

低施磷水平下不同施肥对太湖地区黄泥土磷迁移性的影响

对太湖地区水稻土上长达13年的长期不同施肥处理的某试验田进行了土壤全磷、树脂磷和水溶性磷的测定分析.不同处理的年施磷量为0～53kg/(hm²·a),土壤全磷为0.3～0.5g·k^-1.根据土壤磷素的质量平衡,计算表明该水稻土存在的磷素流失量为2～8kg/(hm²·a),单施化肥下的流失量最大,为配施有机肥处理的2～4倍;水溶性磷的比率在0.2%～0.4%间,且不同施肥实践对其的影响不明显.但单施化肥有使亚表层树脂磷和水溶性磷含量提高的倾向.长期施用化肥配施大量鲜猪粪使树脂磷含量提高20～40 mg·kg^-1,但与长期施用化肥配施秸秆的处理一样没有发生在有机质增加下的磷活化而提高磷流失.这些说明本地区长期单施化肥的水稻土中可能存在强烈的磷流失,且水稻土磷流失并不以水溶解发生.为了防止水稻土磷的强烈水流失而加剧农业非点源污染,要避免长期单施化肥,而应坚持和推广配施适量有机肥.     

封闭景观水体的表观污染机制研究

良好的表观性状是城市水体发挥景观功能的基本条件,现今封闭景观水体的表观受污染严重。以景观园林师陶园内的封闭水体为研究对象,进行为期半年的现场观察和水质监测,运用吸收光谱法研究了水体表观污染的历程,并进行了表观污染指数(SPI)及环境因子间的相关性分析以了解表观污染机制。研究发现,封闭水体的表观污染程度随季节变化明显,SPI与温度(T)、浊度、腐殖酸(UV254)、叶绿素a(Chl-a)均显著正相关,与溶解氧(DO)显著负相关,相关系数分别为0.786、0.951、0.595、0.849、-0.699。结果表明,植物残体的腐烂分解以及浮萍和藻类的竞争性生长会导致水体颜色和浊度异常,甚至出现发黑发臭的严重表观污染现象。     

流化床污泥干燥器床料的颗粒度对流化情况的影响

以上海白龙港污水处理厂流化床污泥干燥系统为研究对象,针对流化床污泥干燥器流化情况的好坏分析,在确定其它变量（流化风量、给料分配器转速、料层压差、运行负荷等）不变的情况下,对床料颗粒度的工艺参数进行研究实验,总结颗粒度的工艺参数对流化情况的运行变化规律,从而提高了流化床污泥干燥系统的稳定性、连续性和高效性。     

Effect of seed sludge on characteristics and microbial community of aerobic granular sludge

Aerobic granular sludge was cultivated by using different kinds of seed sludge in sequencing batch airlift reactor.The influence of seed sludge on physical and chemical properties of granular sludge was studied;the microbial community structure was probed by using scanning electron microscope and polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE).The results showed that seed sludge played an important role on the formation of aerobic granules.Seed sludge taken from beer wastewater treatment plant(inoculum A) was more suitable for cultivating aerobic granules than that of sludge from municipal wastewater treatment plant(inoculum B).Cultivated with inoculum A, large amount of mature granules formed after 35 days operation, its SVI reached 32.75 mL/g, and SOUR of granular sludge was beyond 1.10 mg/(g·min).By contrast, it needed 56 days obtaining mature granules using inoculum B.DGGE profiles indicated that the dominant microbial species in mature granules were 18 and 11 OTU when inoculum A and B were respectively employed as seed sludge.The sequencing results suggested that dominant species in mature granules cultivated by inoculum A were Paracoccus sp., Devosia hwasunensi, Pseudoxanthomonas sp., while the dominant species were Lactococcus raffinolactis and Pseudomonas sp.in granules developed from inoculum B.     

离子阱质谱库的建立与研究

该质谱库建有510种环境中常见有机化合物的质谱数据,其中含中国环境优先控制污染物名单中列入的有机化合物63种,U．S．EPA清洁水法中规定的重点有机污染物95种,覆盖率达80％～90％,该谱库可应用于离子阱检测系统的谱库检索,提高了对未知化合物鉴定的可靠性。      

Microbial biodegradation of microcystin-RR by bacterium Sphingopyxis sp. USTB-05

A strain,USTB-05,isolated from Lake Dianchi,China,degraded the cyanobacterial toxin microcystin-RR(MC-RR) at the rate of 16.7 mg/L per day.Analysis of 16S rDNA sequence showed that the strain was Sphingopyxis sp.Enzymatic degradation pathways for MC-RR by Sphingopyxis sp.USTB-05 were identified.Adda-Arg peptide bond of MC-RR was cleaved and then a hydrogen and a hydroxyl were combined onto the NH 2 group of Adda and the carboxyl group of arginine to form a linear molecule as intermediate product within the ...     

临街建筑群中交通噪声的计算机模拟

给出了临街建筑群中纵深方向的交通噪声计算机模拟预测方法。交通干道上车流采用泊松分布和等车距车流相结合模型，考虑多种车型的不同声功率级。每辆车作为一个点声源，以几何声学方法考虑直达声和有限次反射声对测点的影响。在计算程序中只要输入车流量，车流成份，建筑群中有关巷道宽度，测点在巷子纵深方向距离及背景噪声等数据，计算机便能输出Ｌ１０，Ｌ５０，Ｌ９８，Ｌｅｑ等声级值。模拟结果和实测值基本一致。     

Dietary exposure to di-isobutyl phthalate increases urinary 5-methyl-2′-deoxycytidine level and affects reproductive function in adult male mice

Phthalates are a large family of ubiquitous environmental pollutants suspected of being endocrine disruptors. Epidemiological studies have associated phthalate metabolites with decreased reproductive parameters and linked phthalate exposure with the level of urinary 5-methyl-2′-deoxycytidine(5mdC, a product of methylated DNA). In this study, adult male mice were exposed to 450 mg di-isobutyl phthalate(DiBP)/(kg·day) via dietary exposure for 28 days. Mono-isobutyl phthalate(Mi BP, the urinary metabolite) and reproductive function parameters were determined. The levels of 5mdC and 5-hydroxymethyl-2′-deoxycytidine(5hmdC) were measured in urine to evaluate if their contents were also altered by DiBP exposure in this animal model. Results showed that DiBP exposure led to a significant increase in the urinary 5mdC level and significant decreases in sperm concentration and motility in the epididymis, accompanied with reduced testosterone levels and downregulation of the P450 cholesterol side-chain cleavage enzyme(P450scc) gene in the mice testes. Our findings indicated that exposure to DiBP increased the urinary 5mdC levels,which supported our recent epidemiological study about the associations of urinary 5mdC with phthalate exposure in the male human population. In addition, DiBP exposure impaired male reproductive function, possibly by disturbing testosterone levels; P450scc might be a major steroidogenic enzyme targeted by DiBP or other phthalates.     

DBD降解CF2ClBr过程中自由基与电子能量

利用介质阻挡放电方法对环境污染物ＣＦ₂ＣｌＢｒ进行了等离子体降解的研究．在前人对该体系的降解产物分析及活性粒子推测的基础上,采用动态反应装置得到了等离子体的发射光谱,进一步确证了等离子体系中出现的ＣＦ₂、ＣＦＣｌ、Ｆ、Ｃｌ、Ｂｒ等主要自由基,并从中推出了等离子态气体可能发生的自由基反应．同时通过发射光谱的分析,近似得到该体系的平均电子能量约为２．４２ｅＶ