高效菌处理难降解有机工业废水研究进展

总结了高效菌在造纸、印染、化丁、农药、制药等工业有机废水处理中的研究现状;认为大力开展和加强高效菌的选育和应用工艺研究,是生物强化技术领域今后的发展方向。     

芳香族化合物的生物降解途径

分析了以苯、甲苯、萘和联苯为代表的芳香族化合物的生物降解途径,发现其共同点都是经过两步加氧酶作用生成二醇,最后再开环;介绍了苯、甲苯、萘和联苯这几种芳香族化合物分解酶的组分、相对分子质量及其辅基。     

斜生栅藻与单甲脒的相互作用

为研究斜生栅藻与单甲脒的相互作用,采用评价化学品对藻类毒性的标准实验方法出了单甲凶制斜生栅藻生长的９６ｈ－ＥＣ５０为６．５ｍｇ／Ｌ。实验结果表明,在单甲脒浓度分别为２,４和８ｍｇ／Ｌ下,斜生栅藻都不具备降解单甲 能力。     

Contribution to the Study of Fungal Attack on Some Plasticized Vinyl Formulations

The objective of this study was to develop new vinyl flooring formulations with increased resistance to fungi and microorganisms attack, by using plasticizers having a chemical composition different from that of common di-ethylhexyl phthalate (DOP). It is suspected that during the vinyl flooring life service, the attack of fungi and microorganisms leads to the degradation of DOP and the release of some volatile organic compounds (VOC). For this reason the new materials were formulated with plasticizers having chemical composition different of that of DOP i.e.: diethyleneglycol dibenzoate (2–45), tricresyl phosphate (Lindol) and phenol alkylsulphonic ester (Mesamoll). For the same reason in the new flooring formulations the vinyl polymer, vinyl chloride-vinyl acetate copolymer (VC-VAc), was partially replaced with lignin (L) a natural polymer and major component of wood and vascular plants. Besides its other functions in wood, L imparts resistance to the most microorganisms attack. An organosolv lignin Alcell lignin (AL) was utilized as partial replacement of VC-VAc copolymer.The influence of the new plasticizers, as well as the influence of the partial replacement of VC-VAc copolymer with L on the resistance of the new formulations to fungal attack was evaluated following a standard procedure given in ASTM G 21–2002 “Determining Resistance of Synthetic Polymeric Materials to Fungi”. The evaluation has been undertaken for controls (formulated without AL) and blends (formulated with 20 parts AL) specimens. Test specimens were inoculated with a mixture of five fungi. Following 28 days of incubation at 28°C and 95% relative humidity, the specimens were examinated visual and under the microscope and rated for fungal growth. Weight loss, changes in mechanical properties and changes in glass transition temperature due to the effect of biodeterioration were also determined.Although each plasticizer has a specific resistance to hydrolysis due to differences among ester groups, the visible effects of fungal attack, in formulations without AL, is similar for all plasticized controls, with the exception of formulations incorporating diethyleneglycol dibenzoate (2–45) in which a higher degree of biodegradation was always present. Based on the weight loss of specimens formulated without AL, their resistance to fungal attack can be rated as follows: . The same rating is applicable for blend specimens. The results have demonstrated that each particular AL-plasticizer-additives formulation has its specific mechanism of biodegradation.     

Anaerobic degradation of xenobiotic organic contaminants (XOCs): The role of electron flow and potential enhancing strategies

In groundwater, deep soil layer, sediment, the widespread of xenobiotic organic contaminants (XOCs) have been leading to the concern of human health and eco-environment safety, which calls for a better understanding on the fate and remediation of XOCs in anoxic matrices. In the absence of oxygen, bacteria utilize various oxidized substances, e.g. nitrate, sulphate, metallic (hydr)oxides, humic substance, as terminal electron acceptors (TEAs) to fuel anaerobic XOCs degradation. Although there have been increasing anaerobic biodegradation studies focusing on species identification, degrading pathways, community dynamics, systematic reviews on the underlying mechanism of anaerobic contaminants removal from the perspective of electron flow are limited. In this review, we provide the insight on anaerobic biodegradation from electrons aspect — electron production, transport, and consumption. The mechanism of the coupling between TEAs reduction and pollutants degradation is deconstructed in the level of community, pure culture, and cellular biochemistry. Hereby, relevant strategies to promote anaerobic biodegradation are proposed for guiding to an efficient XOCs bioremediation.     

MD三相流化床降解含酚废水的研究

以人工配制的含酚废水作为研究对象,观察新研制的ＭＤ三相流化床好氧化物处理含酚废水的效果。试验结果表明,在进水酚浓度为４１００ｍｇ／Ｌ时,ＭＤ三相流化同水酚浓度为２０ｍｇ／Ｏ－２５ｍｇ／Ｌ,其     

外加营养源对氯氰菊酯降解菌GF31降解特性的影响

利用本实验室保存的一株铜绿假单胞菌(Pseudomonas aeruginosa)GF31,考察了外加不同的碳、氮源对菌株降解氯氰菊酯特性的影响.实验结果表明:适量浓度的碳、氮源对降解有明显的刺激作用,外加碳源中葡萄糖的刺激作用最为明显,外加0.8 g/L的葡萄糖,氯氰菊酯降解率提高了13.7%;外加氮源中以蛋白胨对微生物的促进作用最突出,当外加5.0 g/L蛋白胨时,氯氰菊酯降解率从27.5%提高到70.0%;降解5 d后,氯氰菊酯的降解已基本趋于平衡.     

焦化废水的微生物脱色

在试验室条件下,分离出3株焦化废水脱色优势菌株,采用恒温连续进水的固定化生物膜系统,研究了焦化放心水中有代表性的难降解污染指标一色度的去除.tHR12h,系统出水色度平均由330倍降至65倍,去除率79.5%以上。     

Comparisons of Geochemical Signatures of Biotransformation of Fuel Hydrocarbons in Groundwater

Biotransformation processes play an active role in reducing the environmental impact of fuel hydrocarbon releases to groundwater. Because monitoring data at release locations are typically sparse, spatial variations in geochemical indicator parameters are often called upon as indirect evidence of biotransformation. These parameters include concentrations of electron acceptors (O₂, NO₃ ^-, SO> ₄ ^2- , reduced redox reaction by-products (Fe²⁺, Mn²⁺, CH₄), as well as bicarbonate alkalinity, pH and E_h. However, background variability in a number of these parameters complicates the task of data interpretation, particularly in the case of small data sets. In this study, correlation analyses are applied to geochemical indicator data at six hydrocarbon groundwater contamination sites in California to identify which parameters are the most reliable indicators. The results of the analyses suggest that the most direct indicators of the local redox environment – Fe²⁺, Mn²⁺, CH₄, E_h – yield the most consistent evidence of hydrocarbon biotransformation. Indicators which rely largely on mass balance – O₂, NO ₃ ^- , SO ₄ ^2- , alkalinity – appear to be less reliable. These findings may provide guidance in both the collection and interpretation of groundwater monitoring data at hydrocarbon contamination sites.     

丙酯草醚降解菌CY的分离、鉴定及其降解特性

采用富集培养的方法,从施用过丙酯草醚除草剂的油菜田中分离筛选出5株以丙酯草醚（ZJ0273）为唯一生长碳源和能源的菌株,选其中降解率高的菌株CY进行研究.根据其生理生化和16S rRNA基因序列相似性分析,鉴定其为芽孢杆菌属（Bacillussp.）.根据对CY的初步研究和简单优化,菌株CY在30 d内对50mg.L^...