单一直接投加微生物修复技术在河流治理中的应用

在无彻底截污和清除内源的状况下,应用单一直接投加微生物修复技术,采用梅花式接种法将本源微生物菌剂直接接入,对无锡市浒溪河水体及底泥进行污染治理实验研究.结果表明:河道水体DO质量浓度提升至2mg/L以上,出水处的CODMn、TP和NH3-N降解率分别可高达43%、56%和58%.结果说明单一的直接投加微生物修复技术在相...     

基于信息扩散视角的虚拟社区用户影响力研究

节点排序研究领域中,少有研究考虑群聚效应下的群体规范对传播效率的影响,这可能导致用户影响力度量的准确性下降。针对这一问题,从信息扩散角度出发,借鉴创新扩散理论与Bass扩散模型,提出一种适用于虚拟社区网络的用户局部影响力度量模型CSA-LL（Cohesive Subgroup Analysis Based Local Leadership）：基于凝聚子群挖掘与分析,定义子群内部信息扩散效率,并结合用户全局影响力,计算模型输出值作为节点排序的依据。爬取近期的豆瓣社区数据进行网络构建,使用AISAS模型等方法验证了该模型输出的用户比PageRank算法和Hits算法结果具有更强的营销能力。使用LT模型进一步验证了模型的有效性和子群信息扩散效率对用户传播能力存在正向影响。再使用多个虚拟社区网络数据集和IC模型,分别验证了模型鲁棒性与结论稳健性。     

高效微生物絮凝剂用于污泥脱水及其动力学研究

从活性污泥中筛选出一株高效微生物絮凝剂产生菌TJ-1,经16S rDNA相似性分析鉴定为奇异变形杆菌（Proteus mirabilis）。将TJ-1在优化培养条件下所产絮凝剂（MBF）用于污泥脱水,并与PAM、PAC进行了脱水效果对比。正交试验结果表明,该微生物絮凝剂用于污泥脱水的最佳条件是：pH=6.5,1%的CaCl2投加量为4%（体积分数）,MBF的投加量为6%（体积分数）;在此条件下污泥脱水率可达82%,比单独投加PAC和PAM的脱水效果好。同时,还研究了该微生物絮凝剂在最佳条件下的污泥脱水动力学,并得到了脱水动力学经验方程。     

Molecular approaches to the assessment of biodiversity in aquatic microbial communities

For the past 20 years, the increased development and routine application of molecular-based techniques has made it possible to carry out detailed evaluations of the biodiversity of aquatic microbial communities. It also offers great opportunities for finding out how this parameter responds to various environmental stresses. Most of these approaches involve an initial PCR amplification of a target, which is generally located within the ribosomal operon. The amplification is achieved by means of primers that are specific to the organisms of interest. The second step involves detecting sequence variations in the PCR fragments either by a cloning/sequencing analysis, which provides a complete characterization of the fragments, or by an electrophoretic analysis, which provides a visual separation of the mixture of fragments according to sequence polymorphism (denaturing or temperature gradient gel electrophoresis, single strand conformation polymorphism) or length polymorphism (terminal-restriction fragment length polymorphism, automated ribosomal intergenic spacer analysis). Other non-PCR-based methods are also commonly used, such as fluorescence in-situ hybridization and DNA re-association analysis. Depending on the technique used, the information gained can be quite different. Moreover, some of these analyses may be rather onerous in terms of time and money, and so not always suitable for screening large numbers of samples. The most widely used techniques are discussed in this paper to illustrate the principles, advantages and shortcomings of each of them. Finally, we will conclude by evaluating the techniques and discussing some emerging molecular techniques, such as real-time PCR and the microarray technique.     

微生物絮凝剂的制备与应用

取杭州四堡污水厂的活性污泥和浙江工业大学校内上塘河边的污泥,用GCI培养基分离纯化后筛选出了能产生絮凝剂的菌种两株(记为L2和T2),并以对高岭土悬液的絮凝效果为基准,研究了产生微生物絮凝剂的优化条件。结果表明:在温度为30℃、pH为5～7、L2和T2的培养时间分别为60h和36h、菌种发酵液的投量为1mL/100mL时絮凝效果最好。应用该絮凝剂处理印染废水的试验结果表明,对SS、色度的去除率较高,并使活性污泥的沉降性能得到了明显改善。     

固定化活性污泥球形颗粒的制备及其性能实验

本文以海藻酸钠和聚乙烯醇(PVA)为包埋剂,并适当添加粉末活性炭和硅藻土作为吸附剂探讨了固定化活性污泥球形颗粒的制备过程.继而以餐厅废水为实验用水对所制备的4种固定化小球进行了性能实验,结果表明:含活性炭配方的固定化活性污泥小球兼有包埋法和吸附法的双重特性.是较理想的固定化微生物形式.     

Microbial and biochemical analysis of dried fish and comparative study using different drying methods

In the present study, certain quality parameters of raw and traditionally sun-dried (TSD) Bombay duck samples are compared with dried fish samples obtained from hot air dryer (HAD), freeze dryer, and a newly developed and patented solar conduction dryer (SCD). The parameters analyzed are total viable count, total fungal count, total volatile nitrogen, and trimethylamine (TMA) content and color. It is found that the experimentally dried fish have better microbial and biochemical quality as compared to TSD fish. This study addresses the issue of unhygienic open sun drying and handling of dried products and the need to adopt use of dryers based on the recently developed appropriate drying technology such as SCD which is expected to be transformed into sustainable technology.     

Natural Green Space and Planning Policy: Devising a Model for its Delivery in Regional Spatial Strategies

Provision of natural green space within the broader umbrella of green infrastructure is now a matter of increasing importance to policy makers and decision takers in the land-use planning system. This paper examines the evolution of this new policy area. Reference is made to research studies dealing with attitudes to such spaces and consideration is given to the ‘quality of life’ agenda when addressing both growth and regeneration strategies. A methodology for the future development and appraisal of such policy is advanced.     

Urban social sustainability: a study of the Emirati local communities in Al Ain

The present research examines the design of the public neighborhoods in the United Arab Emirates in terms of social sustainability, especially in the city of Al Ain. Based on the relevant principles and indicators of social sustainability in neighborhoods both globally and locally, the research began with an evaluation of the dimensions of social sustainability by adopting a qualitative research method. The research tools included conducting face-to-face interviews with representatives of Emirati families living in public neighborhoods, analyses of the design patterns of some selected neighborhoods, field observations and spatial syntactic analyses. Through this multi-phase analysis, a clearer understanding of the level of social sustainability achieved in the design of public neighborhoods in Al Ain has been realized, and some neighborhood design guidelines have been proposed.