Variations of dominant microbial populations in groundwater in response to the leachate from Laogang Landfill

Temporal changes of dominant microbial populations in groundwater in response to the leachate from Shanghai Laogang Landfill were investigated. Concentrations of dissolved redox-relevant species in groundwater suggested that the dominating redox process had changed from denitrification to methane-production/sulfate-reduction due to landfilling. Dominant microbial populations were determined using restriction fragment length polymorphism(RFLP) analyses of 16S rRNA gene libraries, which were further studied by sequencing and phylogenetic analyses. The results indicated that obvious shifts of dominant microbial populations had occurred in groundwater in response to the pollution of leachate. The closest relatives of some dominant clones are accordant with the dominating redox processes determined by hydrochemical analyses, based on the GenBank‘s indications on the ability to perform redox reactions.     

甲苯降解菌的分离、鉴定及其对甲苯的降解特性

从重庆钢铁集团焦化厂脱酚池车间污泥中分离纯化得到一株能以甲苯为惟一碳源和能源的革兰氏阴性菌。根据生理生化实验结果、菌落特征、菌体形态,初步鉴定为假单孢菌属。菌株的最佳生长条件为：pH7、温度35℃、加入量100mL培养基中加入60μL甲苯、接种量5．0％。考察了菌株对甲苯的降解特性,在甲苯质量浓度为150mg/L时,比降解速率达到0．211h^-1。     

垃圾填埋场细菌种群空间分布及组成多样性研究

采用PCR-DGGE技术对垃圾填埋场细菌种群垂直分布及组成多样性进行了研究．结果表明：垃圾填埋场细菌种群组成波动较大,某些种群对环境因子的变化十分敏感．在填埋年龄已达3a的取样点,细菌种群的多样性随着垃圾填埋深度的增加而呈现“多—少—多”的变化趋势。各种群间相对密度也呈现由不均一到均一的变化规律,部分层次优势种和非优势种发生较大变化．填埋深度4．0m至6．25m左右的区域是填埋场微生物区系组成发生变化的过渡区,该区域细菌种群的多样性较小,亲缘关系相差比较大的种交叉在一起,具有明显的过渡特征．从时间因素来看,填埋场同层次微生物群落组成随时间延长,种群构成趋于稳定．表层垃圾1～2a内,细菌种群处于交替更叠的阶段,日趋发育成熟．8．25m以下层次的细菌种群主要受填埋深度影响,与填埋时间关系较小。     

Aerobic degradation of methyl tert-butyl ether by a Proteobacteria strain in a closed culture system

The contamination of methyl ten-butyl ether （MTBE） in underground waters has become a widely concerned problem all over the world. In this study, a novel dosed culture system with oxygen supplied by H2O2 was introduced for MTBE aerobic biodegradation. After 7 d, almost all MTBE was degraded by a pure culture, a member of β-Proteobacteria named as PMI, in a closed system with oxygen supply, while only 40% MTBE was degraded in one without oxygen supply. Dissolved oxygen （DO） levels of the broth in closed systems respectively with and without H2O2 were about 5-6 and 4 mg/L. Higher DO may improve the activity of monooxygemase, which is the key enzyme of metabolic pathway from MTBE to tert-butyl alcohol and finally to CO2, and may result in the increase of the degrading activity of PM1 cell. The purge and trap GC-MS result of the broth in closed systems showed that tea-butyl alcohol, isopronol and acetone were the main intermediate products.     

平面应变工步分析中的一种新方法

基于摩擦约束广义变分不等式原理,对长矩形板镦粗进行详细的塑性加工工步分析.不仅得到了经典结果,同时获得了一些其它有价值的结论.从而进一步证明了广义变分不等原理的正确性和实际操作的可行性和优越性.     

电阻焊电极材料热变形行为的研究

电阻焊电极在焊接过程中 ,承受着高温、高压和高电流的作用 ,工作条件十分恶劣。在导电、导热性能差不多时 ,其高温热稳定性的好坏直接影响它的使用寿命。因此 ,针对 3种典型的电极材料 (CuCr,CuCrZrMg ,弥散铜 ) ,进行了热变形行为研究 ,通过分析在不同高温情况下的应力 应变曲线 ,从而确定其高温热稳定性及使用寿命长短。     

溧阳台体应变异常与地震的对应关系研究

地震预报的基础是要有连续可靠的高质量的观测资料。地震台站一线的工作人员对本台产出的观测资料的可靠性最有发言权,溧阳地震台的体应变观测资料在历年的全国资料质量评比中连续6年获得前三名。本文通过对江苏溧阳地震台体应变观测资料的分析研究,发现1996年11月09日在南黄海6.1级地震和1997年07月28日在南黄海5.1级地震,台湾1999年09月21日7.6级地震和2002年03月31日7.5级地震以及2001年11月14日青海8.1级地震前后,该台体应变资料有较明显的前兆异常反应,并且有一定的变化规律和异常特征,通过对这种规律的总结对地震预报有一定的参考价值,为此,我们对这种规律认真的分析总结,以提供给大家参考。     

高效染料脱色菌的分离鉴定及其脱色特性

从印染废水的处理装置中分离到多株脱色菌，其中一株高效脱色菌经鉴定为腐败希瓦氏菌（Shewanella putrefaciens)。该菌株在合适条件下能有效地去除印染生产上常用的多种染料，在6h内对活性艳红染料的去除率可达到99%-100%，实验还对充氧，温度及共代谢碳源等诸因子对该菌脱色能力的影响进行了研究。     

生物污染

介绍了生的污染的概念和特点，着重讨论了造成生的污染主要因素，如引种，生物有机体的过度繁殖和扩张等，以及畜牧场污水，生物合成工厂废弃物等引起的生物污染。文章呼吁：在研究保护生物多样性整体计划时必须考虑到生物圈污染这一最大的理论问题：要加强移入种和本地种之间相互关系的生太研究；当今最迫切也是最复杂的研究方向是预测生态系统中由人类引起的变化。