循环冷却水系统海生物污损化学控制

分析了滨海电厂主要污损海生物的特性及危害,简述了循环冷却水系统海生物污损的控制方法,并重点介绍了杀生剂处理方法.对比了各类杀生剂的作用机理、使用策略、药剂用量、环境毒性和环保处理等,提出氧化性杀生剂和非氧化性杀生剂交替使用控制海生物污损,并对杀生剂的应用技术进行了探讨.     

A comparison of silver‐ and copper‐charged polypropylene feed spacers for biofouling control

Implementation of nanofiltration (NF) and reverse osmosis (RO) processes in treating traditional water sources can provide a steady‐state level of removal that eliminates the need for regeneration of ion exchange resins or granular activated carbon. Moreover, RO can help meet future potable water demands through desalination of seawater and brackish waters. The productivity of membrane filtration is severely lowered by fouling, which is caused by the accumulation of foreign substances on the surface and/or within pores of membranes. Microbial fouling, or biofouling, is the growth of microorganisms on the membrane surface and on the feed spacer as present between the envelopes. The fouling of membranes has demanded and continues to demand considerable attention from industry and research communities. Many of these applications use membranes in a spiral wound configuration that contains a feed spacer. The goal of this project was to develop low‐biofouling polypropylene (PP) spacers through the functionalization of PP by a spacer arm with metal chelating ligands charged with biocidal metal ions, investigate the use of this metal‐charged polypropylene (PP) feed spacers that target biofouling control, and to use some traditional and one novel techniques to autopsy the membranes after filtration to gain a better understanding of the biofouling mechanism and how the modified spacers are affecting it. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

污损生物对合浦珠母贝Pinctada martensii生长和繁殖的影响

主要研究定期清除污损生物的合浦珠母贝(Pinctada martensii)与不清除污损生物的合浦珠母贝在生长及繁殖上的差异,用以说明污损生物对合浦珠母贝的生长及繁殖的影响.结果表明,合浦珠母贝在悬挂了2个月之后,清除污损生物的实验组与不清除污损生物的实验组合浦珠母贝之间的各项生长指标差异不显著(P>0.05),而在悬挂3个月和悬挂4个月之后,清除污损的合浦珠母贝与不清除污损的合浦珠母贝之间的生长指标产生了显著差异(P<0.05).结果还显示污损生物对合浦珠母贝的繁殖周期没有影响.     

南海生物污损特点及防除对策

生物污损现象对海洋水产养殖、交通运输和近海油气的开采产生极大的危害.文章论述了南海生物污损特点和防除方法,并对今后的防除工作重点进行了展望.     

材料化学性质影响微生物污垢的神经网络分析

用神经网络技术对微生物垢诱导期和平均污垢量建立了评价及预测模型。对文献及作者实验获得的共18个样本进行了拟合评价，结果表明，对诱导期18个样本的评价结果与实测结果全部相符合，准确率达到100％；对平均污垢量，有15个样本的评价结果与实测结果相符合，准确率达到83．3％。对5个样本进行了预测，结果表明，对诱导期和平均污垢量，均有4个样本的预测结果与实测结果相符，准确率达到80％。     

Dynamic Fluoroalkyl Polyethylene Glycol Co‐Polymers: A New Strategy for Reducing Protein Adhesion in Lab‐on‐a‐Chip Devices

Non‐specific adsorption of biomolecules (or “biofouling”) is a major problem in microfluidics and many other applications. The problem is particularly pernicious in digital microfluidics (DMF, a technique in which droplets are manipulated electrodynamically on an array of electrodes coated with a hydrophobic insulator), as local increases in surface energy that arise from fouling can cause droplet movement to fail. We report a new solution to this problem: a device coating bearing a combination of fluorinated poly(ethylene glycol) functionalities (FPEG) and perfluorinated methacrylate (FA) moieties. A range of different FPEG‐FA copolymers were synthesized containing varying amounts of FPEG relative to the fluorinated backbone. Coatings with low%FPEG were found to result in significant reductions in protein adsorption and improvements in device lifetime (up to 5.5‐fold) relative to the state of the art. An analysis of surface topology and chemistry suggests that FPEG‐FA surfaces undergo a dynamic reconstruction upon activation by applying DMF driving potentials, with FPEG groups forming vertical protrusions out of the plane of the device surface. An analysis of changes in surface wettability and adhesion as a function of activation supports this hypothesis. This innovation represents an advance for digital microfluidics, and may also find use in other applications that are currently limited by biofouling.     

超高分子量聚乙烯/石墨烯复合涂层制备及其在海洋装备防护中的应用

目的采用热喷涂技术制备涂层,通过材料选择和结构设计,有效延缓海水对金属基底的腐蚀和冲蚀,并抑制海洋材料表面生物污损等对海洋材料的严重破坏。方法采用高能球磨法制备了聚乙烯-石墨烯(UHMWPE-graphene)复合粉末,用火焰喷涂技术在E235B碳钢基底表面制备UHMWPE和UHMWPE-graphene复合涂层。通过扫描电子显微镜和透射电子显微镜对原始粉末和涂层微观组织进行表征,并通过摩擦磨损实验、电化学测试、生物污损检测,分别评价涂层耐海水冲刷性能、耐腐蚀性能以及抗生物污损特性。结果相对于碳钢和UHMWPE涂层,UHMWPE-graphene复合涂层的腐蚀电位提高和腐蚀电流减小,预示着样品的耐腐蚀特性增强。由于UHMWPE-graphene复合涂层呈现疏水性以及更低的表面能,使其表现出优异的抵抗海藻贴附的能力。添加石墨烯的复合涂层的摩擦系数和磨损率比纯UHMWPE涂层均有一定程度的降低。添加石墨烯质量分数为0.5%时,涂层的摩擦系数由0.236降低到0.195,且磨损率下降了约26%。结论利用火焰热喷涂技术在碳钢表面成功制备了组织致密的UHMWPE涂层、UHMWPE-0.2%graphene和UHMWPE-0.5%graphene复合涂层。石墨烯的添加,能够有效提高涂层在模拟海洋环境中的耐蚀性、抗生物污损性及耐磨性。     

海洋生物污损与材料腐蚀

总结近年来海洋生物污损和材料腐蚀相关的研究进展,综述了海洋生物污损和材料表面腐蚀的关系。分别阐述了微观生物污损与材料表面腐蚀的相关性,宏观生物污损与材料表面腐蚀的相关性,分析两者或促进或抑制的机理。最后提出了需要进一步探讨的问题。     

Effect of Membrane Surface Properties During the Fast Evaluation of Cell Attachment

Abstract

The biofouling potential is one of the important factors to design and to select membranes for water and wastewater treatment. In this investigation, the effect of membrane surface properties during the attachment of S. cerevisiae cells was examined using a laboratory‐scale membrane filtration cell enabling direct microscopic observation of microbial cell deposition. The experimental results from 6 commercially available membranes showed that the initial adhesion rate, k _d , was affected by the zeta potentials, hydrophobicity, and roughness of membrane surfaces. The k _d value was significantly lower at the membrane which had more negative, hydrophilic, and smooth surfaces. The results will be helpful to minimize the time for selecting membranes in different situations, and for testing the performance of newly designed membranes.     

热泵工况下竖直不锈钢表面微生物污垢动态生长行为

城镇二级出水所含致垢微生物将导致其热能回用过程中在换热面上形成以微生物污垢为主的混合污垢,影响换热、流动效率。以可控微生物种类及浓度的模拟二级出水为介质,对典型热泵供暖、制冷工况下微生物污垢在模拟板式换热器的竖直不锈钢壁面上的形成过程进行了研究,关注起始阶段垢层微观结构演变与宏观垢量生长特性,并考查了流速、菌浓度对成垢过程的影响。实验表明：垢层微观结构演变与宏观垢量增长存在同步关系,污垢生长速率对应于微观结构演变;流速对于成垢过程影响呈非单调性;菌浓度低至10³ CFU·ml^-1（CFU,菌落形成数）时成垢量可忽略。实验结果可指导除垢时间点的选择及改进抑垢、除垢方法。