Siloxane‐based copolymers for use in two‐phase partitioning bioreactors

Two‐phase partitioning bioreactors (TPPBs) have been recently demonstrated to be capable of using solid polymers as the absorbing/desorbing phase. In this paper, we examine the possibility of using a siloxane‐based copolymer as this phase. Copolymers were prepared using vinyl terminated oligo(dimethylsiloxane‐co‐diphenylsiloxane), copolymerized with varying amounts of the comonomers ethylene glycol dimethacrylate (EGDMA), N‐vinyl pyrrolidone (NVP), or acrylic acid (AA), via free radical polymerization. The absorption rate of phenol as a representative pollutant into these polymers from water was measured. The inclusion of a water‐soluble comonomer resulted in swelling of the polymers in water, enhanced total phenol absorption, but reduced phenol diffusivity.     

Novel Application of Cyclolipopeptide Amphisin: Feasibility Study as Additive to Remediate Polycyclic Aromatic Hydrocarbon (PAH) Contaminated Sediments

To decontaminate dredged harbor sediments by bioremediation or electromigration processes, adding biosurfactants could enhance the bioavailability or mobility of contaminants in an aqueous phase. Pure amphisin from Pseudomonas fluorescens DSS73 displays increased effectiveness in releasing polycyclic aromatic hydrocarbons (PAHs) strongly adsorbed to sediments when compared to a synthetic anionic surfactant. Amphisin production by the bacteria in the natural environment was also considered. DSS73's growth is weakened by three model PAHs above saturation, but amphisin is still produced. Estuarine water feeding the dredged material disposal site of a Norman harbor (France) allows both P. fluorescens DSS73 growth and amphisin production.     

Synthesis and characterization of monodispersed orthorhombic manganese oxide nanoparticles produced by Bacillus sp. cells simultaneous to its bioremediation

A heavy metal resistant strain of Bacillus sp. (MTCC10650) is reported. The strain exhibited the property of bioaccumulating manganese, simultaneous to its remediation. The nanoparticles thus formed were characterized and identified using energy dispersive X-ray analysis (EDAX), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD) and atomic force microscopy (AFM). When the cells were challenged with manganese, the cells effectively synthesized nanoparticles of average size 4.62 ± 0.14 nm. These were mostly spherical and monodispersed. The ex situ enzymatically synthesized nanoparticles exhibited an absorbance maximum at 329 nm. These were more discrete, small and uniform, than the manganese oxide nanoparticles recovered after cell sonication. The use of Bacillus sp. cells seems promising and advantageous approach. Since, it serves dual purposes of (i) remediation and (ii) nanoparticle synthesis. Considering the increasing demand of developing environmental friendly and cost effective technologies for nanoparticle synthesis, these cells can be exploited for the remediation of manganese from the environment in conjunction with development of a greener process for the controlled synthesis of manganese oxide nanoparticles.     

Pilot studies for in-situ aerobic cometabolism of trichloroethylene using toluene-vapor as the primary substrate

In-situ pilot studies of aerobic cometabolism were conducted to evaluate the injection of toluene-vapor and air into TCE-contaminated aquifer. Delivery of primary substrate (toluene) in a vapor state with air enhanced the growth of indigenous toluene-utilizing bacteria that would degrade TCE by aerobic cometabolism. Meanwhile, delivering toluene in a vapor state effectively reduced potential clogging near the injection points due to excessive microbial growth, which was observed in the field when the injection of neat toluene was employed. Over 90% removal of TCE was achieved with primary substrate (toluene) degraded to a concentration below 10 microg/L.     

地下水污染生物修复技术研究进展

综述了几种地下水污染生物修复技术的研究进展,探讨了各自的优缺点.重点分析了地下水污染生物修复技术目前存在的问题及其今后的发展趋势.     

生化工程的延伸效应对富营养化水库的生物修复作用

依靠长距离明渠引水补给的城市供水水库，由于明渠水被污染而水库呈现富营养化，经兴建大型生物氧化工程处理明渠原水后，显著改善了水库的进水水质。生化工程的延伸效应明显提高了水库的自净能力，水库得到了显著的生物修复效果。     

污染河流治理与修复技术现状及展望

对河流治理与修复技术进行了综述,将其归纳为物理、化学、生物修复技术三大类:物理技术包括人工曝气、引水冲污、底泥疏浚;化学技术包括化学除藻、重金属固定;生物修复技术包括微生物强化、植物强化、生物膜法。对每种技术的研究现状进行了简介和评价,并展望了这三类技术今后的发展方向。     

水体中石油污染的生物修复

生物修复是处理水体中石油污染较好的一种方法,本文简述了水体中石油污染的来源、危害,石油污染生物修复技术的概念,对水体中石油的可生物降解性,微生物种类、降解机制和降解过程的影响因素以及目前的研究方向进行了较全面的综述,并对石油污染的研究现状和存在问题进行了讨论。     

污染土壤修复技术介绍

本文简要介绍了污染土壤治理的各种方法,包括换土法、化学修复、生物修复、电修复、热修复等的基本原理、适用范围及其基础研究和应用的最新进展。     

降解萘的假单胞菌ND24菌株的分离和萘污染土壤的生物修复

用富集培养法从石油工业废水中分离到高效降解萘的ND24菌株．该菌株能以萘为惟一碳源生长，在48h内将无机盐培养基中2g／L的萘降解98．4％．该菌株还能降解水杨酸、对羟基苯甲酸、邻苯二甲酸和苯乙酸．16SrRNA基因测序和同源序列比对表明，ND24菌株属于假单胞茵（Pseudomonas sp．）．将ND24菌株接种到含有0．2g／dL萘的灭菌土壤中，经过14d室温培养以后，萘的去除率为98．2％．