污水处理中物化与兼性生化低温下的协同作用

针对兼性生化低温状态去除效果差、污泥易流失等问题,提出采取物化兼性生化联用法来提高其处理效果.并采用对比法研究物化、兼性生化及二者联用技术处理低温城市污水.研究结果表明在聚合氯化铝（PAC）投加量为20mg/L时,物化与兼性生化在COD、浊度及TP的去除方面表现出良好的协同作用,但脱氮效果一般;二者协同作用能以较小的投药量有效改善低温状态兼性生化处理效果及污泥流失现象,为后续生态单元的稳定运行提供了保障.     

Biodegradation of low‐density polyethylene/thermoplastic starch foams before and after electron beam irradiation

Foamy low‐density polyethylene/plasticized starch (LDPE/PLST) blends at different compositions were produced in the presence of azodicarbonamide (ACA) compound as foaming agent. The LDPE/PLST blends before and after electron beam irradiation were investigated in terms of mechanical properties, bulk density, and structure morphology. Moreover, the biodegradability of these materials was evaluated by the soil burial test for 2 months, in which the buried sheets were also examined by scanning electron microscopy (SEM). The results showed that the increase of PLST content from 24 to 30% was accompanied by a decrease in the yield and break stresses of 10 and 20% for the unirradiated blends without the foaming agent, respectively. Further decrease in these mechanical parameters was observed after the foaming process. The bulk density, void fraction, cell size measurements as well as the examination by SEM illustrate clearly the cell growth of the foam structure. The soil burial test and SEM micrographs indicate the growth of microorganisms overall the blend sheets and that the blend was completely damaged after two months of burying. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

油脂废水处理中高效菌株的应用

通过对外界获取的菌种进行筛选和育种,可得到高效油脂降解菌,提高油脂废水的处理效率和处理效果。介绍了目前高效油脂降解菌在油脂废水处理中的应用现状,并指出了未来该领域的发展方向。     

免水型生态卫生设施用降解菌的分离筛选

本文对免水型生态卫生设施中的生物填料及施有机肥农田的土壤进行了人类粪便降解菌的分离。筛选得到的各菌种在实验条件下,降解粪便效果较好,除臭除味,COD下降率在30％左右。其中在土壤中分离出来的9号菌,COD下降率达41％,全部菌种复合培养处理的下降率高达59％。结果表明,实验采用的分离筛选方法是比较有效的,筛选得到了具有较好降解效果的菌种,为降解菌的进一步试验打下了基础。     

萘降解菌的筛选及降解性能的初步研究

微生物降解是多环芳烃从土壤和水环境中消失的主要途径。本文从加油站废油排放口附近被污染土壤中筛选到两种降解萘的混合菌H1、H2并从中分离出一株纯菌C_1。研究发现,利用纯无机盐培养基加萘作为唯一碳源要比加入其它营养物质的培养基对于筛选萘降解菌更为有利。H_1、H_2和C_1均能以萘为唯一碳源生长,在萘初始浓度为1000mg/L的纯无机盐培养基中培养40h后,培养液中微生物数量分别增长10倍以上,利用气相色谱测得萘的降解率都达到99．6％以上。     

海洋中石油烃类降解与微生物腐蚀关系研究

在工程实践中,国家重要的海洋工程设施（如海底输油管线和船舶燃料系统等）发生的腐蚀破坏案例常常涉及到油水环境,并与微生物腐蚀作用密切相关,而了解海洋含油环境中石油烃类的生物转换机制是了解微生物腐蚀的关键。阐述了海洋环境中降解石油烃类的主要微生物及其降解机制,其在有氧和无氧条件下呈现不同的特点。微生物降解石油烃类过程中非常重要的一步即为接受电子,该过程将生物无法直接利用的化学能转换成可直接利用的能量形式,即腺苷三磷酸（ATP）。有氧条件下的烃类降解以氧气作为最终电子受体,而在缺氧条件下可利用硝酸盐、铁离子、硫酸盐等作为电子受体。海洋环境中的石油烃类会促进腐蚀性硫化物的生成,因此油水环境下的微生物腐蚀机理以硫化物的腐蚀破坏为主。此外,烃类降解过程产生的琥珀酸等酸性中间代谢物也会加剧腐蚀的发生。但目前关于海洋油水环境中微生物群落作为一个整体展现出的功能性及其对钢铁设施的破坏机理,仍然缺乏系统性的研究,而基于高通量测序的微生物组学研究技术将成为有效解决这些问题的手段之一。     

难降解有机物的处理技术进展

本文查阅了国内外大量文献,从中整理归出近年来对于难生物降解有机物的处理技术的发展动态,并介绍了一些技术的典型应用,加以一定的评述。     

可生物降解热熔胶粘剂的研究进展

综述了近年来可生物降解热熔胶的发展、合成、性能、应用、最新的研究进展。     

Design of tailored biodegradable implants: The effect of voltage on electrodeposited calcium phosphate coatings on pure magnesium

Magnesium, as a biodegradable metal, offers great potential for use as a temporary implant material, which dissolves in the course of bone tissue healing. It can sufficiently support the bone and promote the bone healing process. However, the corrosion resistance of magnesium implants must be enhanced before its application in clinical practice. A promising approach of enhancing the corrosion resistance is deposition of bioactive coating, which can reduce the corrosion rate of the implants and promote bone healing. Therefore, a well-designed substrate-coating system allowing a good control of the degradation behavior is highly desirable for tailored implants for specific groups of patients with particular needs. In this contribution, the influence of coating formation conditions on the characteristics of potentiostatically electrodeposited CaP coatings on magnesium substrate was evaluated. Results showed that potential variation led to formation of coatings with the same chemical composition, but very different morphologies. Parameters that mostly influence the coating performance, such as the thickness, uniformity, deposits size, and orientation, varied from produced coating to coating. These characteristics of CaP coatings on magnesium were controlled by coating formation potential, and it was demonstrated that the electrodeposition could be a promising coating technique for production of tailored magnesium-CaP implants.