反静电场处理厌氧污泥的影响因素分析

在电场和电解副效应的共同作用下,厌氧污泥上清夜COD、NH4 -N和VSS变化率随电流强度呈抛物线型变化.电场对污泥参数的影响存在着最佳的工作电流强度,污泥的性质影响反/静电场处理污泥的效果.     

壳聚糖季铵盐处理玉米酒精清糟液的研究

介绍了新型高效无毒天然高分子混凝剂壳聚糖季铵盐（GTCC）的制备，将GTCC和壳聚糖对玉米酒精发酵清糟液分别进行絮凝处理，结果表明，GTCC的絮凝效果明显优于壳聚糖，以黑龙江肇东华润金玉酒精厂清糟作为研究对明，当GTCC投加量为3mg/L（用量仅为壳聚糖的二十分之一左右）时，CODCr的去除率率达到25％，浊度去除率达78％，初步分析表明，壳聚糖季胺盐强的电中和能力是具有好的絮凝能力的主要原因。     

原油罐清罐作业危险因素分析与对策

应用安全系统工程方法和事故树法,识别分析清罐作业的主要危害及潜在风险,剖析危害产生的根源,提出现有原油储罐清罐作业的安全对策。     

晚清赈灾思想研究述评

近年来史学界对晚清赈灾思想的研究取得了长足进展,研究内容侧重于两个方面:官赈思想和义赈思想。官赈思想研究表现在某一人物的个体赈灾思想研究和群体赈灾思想研究;义赈思想研究主要表现在经元善的义赈思想和由官赈到义赈思想转型两个方面。总体来看,史学界对于晚清赈灾思想的研究取得了一定成果,但也存在诸如理论方法、研究内容、史料建设等方面的问题与不足。     

修饰壳聚糖微球用于含蛋白废水处理研究

采用反相悬浮法,以甲醛为预交联剂,环氧氯丙烷交联、氯乙酸羧化制备交联羧化壳聚糖微球,用红外光谱和扫描电镜对微球进行表征,并用于牛血清白蛋白的吸附研究。考察了吸附时间、溶液pH值、牛血清白蛋白的浓度、温度、氯化钠含量等因素对牛血清白蛋白吸附的影响。结果表明,羧化改性交联CTS微球不溶于酸和碱,对牛血清白蛋白具有良好的吸附性能,在pH5.0时,吸附在1h内可达平衡,吸附数据符合Langmuir等温方程。     

洗槽机清洗头升降故障原因分析及对策

针对洗槽机清洗头运行中的升降故障进行了原因分析,找出了解决方法,为今后类似的故障检查和排除提供了借鉴。     

Validation of a conductometric bienzyme biosensor for the detection of proteins as marker of organic matter in river samples

This article describes a conductometric bi-layer based bienzyme biosensor for the detection of proteins as a marker of organic matter in rivers. Proteins were chosen to be used as indicators of urban pollution. The working mechanism of the bienzyme biosensor is based on the enzymatic hydrolysis of proteins into several fractions (peptides and amino acids), which results in a local conductivity change depending of the concentration of proteins. In this work, we began with the optimization of biosensor response using bovine serum albumin (BSA) as standard protein. For this objective seven enzymatic biosensors were prepared: four enzymatic sensors with only one layer of enzyme (proteinase K, trypsin, pronase or protease X) and three other enzymatic sensors with two layers (first layer: membrane containing proteinase K; second layer: one of the three other enzymes: trypsin, pronase or protease X). The biosensors were obtained through the deposition of enzymatic layers and the cross-linking process between enzymes and BSA in saturated glutaraldehyde vapour. The response of the various biosensors, described previously, were compared with the values of total organic carbon (TOC), and those of organic nitrogen (Norg), as determined by the laboratory accredits (CEMAGREF of Lyon) using the traditional method of analysis (NF EN 1484, infrared spectroscopy) and (NF EN 25663, mineralization/colorimetry assay) respectively for each water sample obtained from di erent sites in Lyon (France). The linear correlations obtained with the response of the seven biosensors showed the most important indices of correlations for the biosensor with two enzymatic layers: proteinase K + pronase (pkp). The optimum conditions for the preparation of the pkp biosensor increased the sensitivity and gave a limit of quantification of 0.583 g/L for TOC and 0.218 g/L for Norg in water samples. This sensor shows good reproducibility (2.28%), a capacity to be used at temperatures range 10– 30°C (depending on the season) and moreover a long lifetime (5 weeks).     

十二烷基苯磺酸钠与牛血清白蛋白的相互作用

在生理pH值条件下用荧光光谱和紫外吸收光谱研究了十二烷基苯磺酸钠(SDBS)与牛血清白蛋白(BSA)的相互作用。SDBS可以使BSA的内源荧光发生猝灭,其猝灭机理为静态猝灭。在所研究的浓度范围内获取了SDBS与BSA的结合常数(298K:1.52×105L/mol;310K:7.96×104L/mol)及对应温度下结合反应的热力学参数(ΔH=-41.78kJ/mol;ΔS=-41.00J(/mol·K)/-40.95J(/mol·K);ΔG=-29.56kJ/mol/-29.08kJ/mol)。根据热力学参数推断二者之间的作用力主要为氢键和范德华力。同步荧光光谱表明SDBS的存在改变了BSA的分子构象,BSA分子内的色氨酸残基疏水环境增强。     

模拟和光谱相互验证2'-OH-BDE-28对HSA构象的影响

利用分子对接、分子动力学模拟(molecular dynamics simulation,MD)和光谱法研究2'-羟基-2,4,4'-三溴二苯醚(2'-OHBDE-28)与人血清白蛋白(HSA)的作用机制。MD模拟研究表明2'-OH-BDE-28诱导HSA的内部疏水性增强,结构松散膨胀,致使其二级结构发生改变;圆二色光谱实验与MD模拟结果相吻合,验证2'-OH-BDE-28可诱导HSA的构象变化。荧光光谱实验表明,2'-OH-BDE-28能通过静态猝灭和非辐射能量转移机制引起HSA荧光猝灭。分子对接推断2'-OH-BDE-28以氢键和疏水作用力键合在HSA的位点I处;热力学分析和竞争实验结果一致验证分子对接结果。本文将计算模拟和光谱实验相结合,从模拟和实验2个角度共同探讨2'-OH-BDE-28与HSA的作用机制,结果高度吻合。     

联苯胺对牛血清白蛋白的荧光猝灭作用研究

用荧光光谱和紫外吸收光谱研究了联苯胺(BD)对牛血清白蛋白(BSA)的荧光猝灭作用.结果表明,联苯胺可以有规律地使BSA内源荧光猝灭,其猝灭机理为联苯胺与BSA形成复合物的静态猝灭.获得了不同温度下,联苯胺与BSA作用的结合常数和热力学参数,根据所得结果可推断联苯胺与BSA的主要作用力为氢键和范德华力.由Forster非辐射能量转移理论计算得出了联苯胺与BSA结合位置的距离.