大尺寸弱阴离子交换晶胶层析一步法分离ATP的实验研究

使用一种新型的大尺寸弱阴离子交换晶胶柱从酵母细胞发酵液中一步分离纯化广泛应用于临床治疗的高能化合物三磷酸腺苷(ATP)。该晶胶柱高150mm,直径140mm,柱体体积达到2300mL。实验测定了晶胶柱的孔隙率和等板高度等基本性能参数。层析过程以去离子水为冲洗液,分别用0.03、0.4和1mol·L-1NaCl溶液在2cm·min-1流速下进行洗脱。发现0.03mol·L-1NaCl溶液能把大部分杂质洗脱,0.4mol·L-1NaCl溶液洗脱后能获得纯度较高的ATP。洗脱下来的ATP样品通过高效液相色谱(HPLC)定量分析,回收的ATP纯度达95%～97%,总回收率49.1%。与其它已有方法相比,本法耗时少,工艺简单,降低了ATP变性的风险;在层析过程中以去离子水代替酸液作为冲洗剂和洗脱液溶剂,降低分离过程成本。     

基于遗传算法的高压长线路双端故障测距研究

为提高高压长线路故障定位的准确度,提出了一种基于遗传算法的故障定位新方法。该方法基于线路分布参数模型,按照故障线路两端沿线向对端推得的故障点电压幅值相等的原则列写故障测距方程,并通过相量法对电压分布函数的单调性进行分析,得到伪根判别法则的数学表达式;引入遗传算法求解故障测距方程,采用群体搜索和多父体重组策略,自适应和容错能力强且能够保证解群搜索的遍历性和快速性;在一次搜索中算法可求得故障距离的多个解,有利于伪根的判别。ATP仿真结果和实际应用证明了该方法不受过渡阻抗、故障类型及不同步角的影响,计算速度快且精确度高。     

基于ATP模型下的消弧线圈接地系统特性分析

简单阐述了经消弧线圈接地系统的特性,描述了在ATP下的电弧模型,并应用ATP搭建模型,仿真分析中性点非直接接地系统在不同故障情况下的特征,最终应用仿真图形充分验证了中性点经消弧线圈接地系统的主要特性。     

采用MOA的输电线路雷电响应分析模型

用ATP仿真研究了 110kV线路雷击响应的一些杆塔和线路模型 ,指出分段传输线模型是较合理的杆塔模型。仿真结果有助于制定用带串联间隙线路避雷器来降低线路雷击事故的相应措施。     

CO_2激光照射对表皮LC的影响

郎格罕氏细胞(Lange Hans cell.LC)是从骨髓中的前体细胞衍化而来的树突状细胞,主要位于表皮基层上方.有摄取抗原、处理抗原和传递抗原的功能,起着免疫系统外围前哨的作用.LC的功能可受各种理化因子的影响,是否也会受到激光照射的影响?鲜见文献报道.本文探讨低功率CO2激光照射后,表皮LC的数目形态和分布的情况.     

电感型限陡避雷器的研制

雷电流陡度是雷电流产生破坏的重要原因之一。从电磁波弥散现象出发,用电感型阻抗对闪电限流并将其运用在线路防直击雷上,研制一种新型的防直击雷装置一电感型限陡避雷器。通过ATP仿真和实验结果表明,限陡避雷器的使用,能有效的降低雷电流陡度,降低塔顶电位。限陡避雷器为电力系统防雷又提供了一个新的手段。     

Biomass Recovery Method for Adenosine Triphosphate (ATP) Quantification Following UV Disinfection

A biomass recovery method was developed to monitor UV disinfection efficacy using adenosine triphosphate (ATP). Typically, disinfection monitoring at wastewater treatment facilities (WWTFs) involves quantifying fecal and total coliforms or colony forming units, the results of which take a minimum of 24 h to produce. ATP quantification immediately before and after UV treatment, which takes only minutes, shows little reduction and often an increase in the microbial population since UV irradiation results in cells that are viable (i.e., still producing ATP) but not culturable. To overcome this, our biomass recovery method incorporates an incubation step to encourage life cycling of microbes. Average log reductions in cellular ATP (cATP) were found to be ?0.28 ± 0.19, ?0.011 ± 0.153, ?0.17 ± 0.32, and 0.065 ± 0.074 using direct ATP measurements on UV-treated samples from WWTFs A, B, C, and D, respectively, while those using the recovery method were correspondingly 0.17 ± 0.34, 1.8 ± 0.8, 0.20 ± 0.35, and 0.72 ± 0.26. The response of the biomass recovery-ATP method indicated a significant direct correlation to the microbial population reduction observed in heterotrophic plate count (HPC) and Colilert® methods using both pure Escherichia coli culture and secondary municipal wastewater effluent.     

变压器相移对故障分析模型的影响

传统故障分析方法中常采用忽略相移影响的漏抗模型作为变压器模型,当需要考虑变压器相移影响时,再利用相移公式分别对正、负序分量进行修正。为了明确这种在变压器模型之外考虑相移作用的方法对故障分析结果的影响,分别建立了传统的变压器模型与由3台单相饱和变压器按照实际连接组别连成1台三相变压器的电磁暂态仿真程序(ATP)仿真模型,在线路发生各种不对称短路故障的情况下,考虑相移作用,计算了上述2种不同模型下的变压器两侧的电气量,以ATP仿真模型为参照进行了定量的误差分析,对传统方法的准确度进行了研究。     

基于数学形态学的超高压输电线路暂态保护选相新方案

在分析超高压电网中发生各种故障类型模分量的特征基础上,通过提取信号暂态数据窗能量谱,提出了一种利用数学形态学梯度提取暂态电流故障特征进而识别故障类型的新方案.通过一个典型500 kV双端系统进行的大量ATP仿真计算表明,在不同位置、过渡电阻、故障初始角的情况下发生各种故障均能正确、快速地识别故障相,与传统算法相比计算量较少,且具有更高的灵敏度和更快的故障响应速度.     

Application of ATP bioluminescence for evaluation of surface cleanliness of milking equipment

The ATP bioluminescence method was used to evaluate the cleanliness of milking equipment surfaces (teat cup rubbers, teat dip containers, milk receivers, and pipeline joints) in dairy farms in Galicia (northwest Spain) with parlour, pipeline tie-stall or bucket tie-stall milking systems. The cleanest surfaces were teat cup rubbers. The use of non-chlorinated water for cleaning, and of pipeline or bucket tie-stall milking systems, was associated with high ATP bioluminescence values. However, ATP bioluminescence values only explained 12% of the variability in bulk-tank bacterial count; this is attributable to the importance of other factors (notably the correct functioning of the tank cooling system) for maintenance of low bacterial count.