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Ecology
Published in Paul Pumpens, Single-Stranded RNA Phages, 2020
Sano et al. (2006) were more optimistic about filtration feasibility and showed that the microfiltration of sewage sludge and treated wastewater on membranes with a pore size of 0.1 μm ensured removal of the RNA phages and indigenous noroviruses. Later, the MS2 removal testing led to the conclusion that ultrafiltration followed by UV irradiation was more efficient in terms of energy consumption than coagulation followed by ultrafiltration (Lee S et al. 2013). Further, ultrafiltration combined with coagulation-sedimentation was evaluated for reduction of the spiked phage MS2, among many other indicators, in a pilot-scale water reclamation plant in Okinawa, Japan (Lee S et al. 2017a,b). Finally, different combinations of ultrafiltration, nanofiltration, coagulation, UV irradiation, and reverse osmosis were studied over 2010–2014 in a pilot plant in Japan with the phage MS2 as an indicator (Yasui et al. 2018). It was concluded that reclaimed water could be considered acceptable for recreational enhancement by adding a UV, a nanofiltration membrane, or a reverse membrane treatment to the ultrafiltration membrane treatment process.
Evolution of Hemodialysis Technology
Published in Sirshendu De, Anirban Roy, Hemodialysis Membranes, 2017
Nanofiltration (NF) is closer to RO in its performance but is relatively more porous. It results in partial retention (65%–80%) of monovalent salt (NaCl). The average pore size of the NF membrane is between 5 and 20 Å. The TMP requirement for NF is less, and it is typically between 15 and 25 atm. Solutes of molecular weight between 200 and 1000 Da are separated by NF. The transport mechanism is mainly permeation. Dyes and smaller-molecular-weight organic substances, such as polyphenols, are separated by NF.
The Study of the Effect of UV-C Radiation on the Current–Voltage Characteristics of Chitosan Membranes
Published in Pandit B. Vidyasagar, Sagar S. Jagtap, Omprakash Yemul, Radiation in Medicine and Biology, 2017
Ni Nyoman Rupiasih, Made Sumadiyasa, Putu Erika Winasri
The numerous membranes have been developed for use in reverse osmosis, nanofiltration, ultrafiltration, microfiltration, pervaporation separation, and electrodialysis and in medical use such as artificial kidney [6]. Among these membranes, ion-exchange membranes are one of the advanced separation membranes. It has been used not only as electrodialysis concentration or desalting of solutions, diffusion dialysis to recover acids and electrolysis of sodium chloride solution but also in various fields as a polymeric film having ionic groups [7].
The effect of different carbon sources on biofouling in membrane fouling simulators: microbial community and implications
Published in Biofouling, 2022
Johny Cabrera, Hao-yu Guo, Jia-long Yao, Xiao-mao Wang
Nanofiltration (NF) is being more widely used for the enhanced treatment of micro-polluted source water for the production of drinking water (Kolpin 2002; Liu et al. 2020). The role of NF membranes is becoming more significant as drinking water quality regulations become more rigorous and the desire for higher quality drinking water increases. Nanofiltration is highly effective at removing micropollutants and natural organic matter (NOM) while preserving most of the mineral salts in the treated water (Ventresque et al. 2000; Houari et al. 2013). Membrane fouling is one of the most difficult operating issues that NF must deal with. Membrane fouling is classified into three types: inorganic fouling, organic fouling, and biofouling (Schäfer et al. 2004). Membrane fouling causes a slew of issues, including increased energy use, decreased water flux, and higher channel pressure drops (Flemming 2002, 2020; Dreszer et al. 2013, 2014; DuPont 2020). Biofouling is the most important sort of foulant found in NF systems since it is widespread in membrane systems on the one hand and difficult to control and remove on the other. A membrane fouling simulator (MFS) (Vrouwenvelder et al. 2006, 2007; Farhat et al. 2019) is one of the tools used to investigate biofouling in spiral wound membranes. It measures the pressure drop along the feed channel as an indicator of biofouling.
Human platelet lysates for human cell propagation
Published in Platelets, 2021
Lassina Barro, Pierre-Alain Burnouf, Ming-Li Chou, Ouada Nebie, Yu-Wen Wu, Ming-Sheng Chen, Miryana Radosevic, Folke Knutson, Thierry Burnouf
Another “orthogonal” virus-reduction approach was a combination of psoralen/UVA treatment of PCs with virus removal by nanofiltration of HPL-supplemented medium using a sequence of 35- and 19-nm filters [37]. The resulting nanofiltered HPL medium showed superiority to FBS for expanding BM-MSCs, although, not unexpectedly, some effect of the nanofiltration could be detected on MSC properties compared to the non-nanofiltered medium. Interestingly, nanofiltration could remove 3 log levels or more of platelet-derived extracellular vesicles (EVs) present in the medium. Nanofiltration is a robust technology capable of removing both enveloped or non-enveloped viruses [38], and, potentially, prions [39–41], by a size-exclusion mechanism. Nanofiltration of the whole growth medium also protects cell cultures from viral contamination by ancillary materials as well as due to air-borne contamination [39]. The same study also reported that nanofiltration can be applied to media supplemented with another type of HPL (which is serum converted to remove coagulation factors and fibrinogen) made from non-pathogen-reduced PCs [37].
The purification and functional study of new compounds produced by Escherichia coli that influence the growth of sulfate reducing bacteria
Published in Egyptian Journal of Basic and Applied Sciences, 2020
Oluwafemi Adebayo Oyewole, Julian Mitchell, Sarah Thresh, Vitaly Zinkevich
Another technique central to the control of SRB is the inhibition of their growth or activity. Many approaches have been tried to limit SRB growth in industries so that the production of hydrogen sulfide is prevented. These include the use of nanofiltration, biocompetitive exclusion, chemical inhibitors, biocides and coatings. However, the use of these methods has proved to be expensive, ineffective, or impracticable in the field. Microorganisms and the products of their metabolism are able to degrade most biocides, coatings and chemical inhibitors [27–29]. Also, incidences of equipment failure have been reported with the use of some biocides and most of the biocides are toxic and therefore pose danger to the environment [30,31]. In addition, many of the chemically derived antifouling agents are not environmentally friendly [31]. These account for why urgent research is directed toward the use of microbial metabolites to inhibit the growth of SRB through the production of antifouling enzymes, antimicrobial agents and chemical signals [31].