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Effects of membrane fouling on the operation of low pressure reverse osmosis system for water treatmentTsai, Wen-Chin 27 August 2012 (has links)
The tap-water treated by water treatment plants in southern Taiwan is coming from surface water of the rivers, subsurface stream and underground water of deep wells. The original raw water possesses were high level of hardness and ammonia- nitrogen solute due to affection by terrain, geology and human activities within water origin area. And considering the water quality from Kao-ping river origin is hard to control during in rain fall and dry season, we were to construction efficiency procedure of water treatment to obtain a high quality of drink water. There were high hardness and TDS from strata limestone of groundwater to increase treatment difficulty in southern Taiwan water treatment plant. Therefore, recommended that the influent water standards were limited hardness and silicate (SiO2) less than 300 mg/L and 15 mg/L, respectively. On the other hand, the metal substances Ca, Mg, Si and Al in influent water were 74.3 mg/L, 18.7 mg/L, 12.9 mg/L and 0.1 mg/L, respectively. Results show high inorganic substances that could increase the treatment loading. This project of the study, were make sure the problem of membrane clogging and fouling happened to the finest water treatment plants who use LPRO membrane system to remove the impurity in the influent water. Moreover, by accumulation of processes operation experience on site were according to water quality statistics data and membrane autopsy of single LPRO membrane by processes. In the same time, we prepared three single tube of RO membrane to experiment on site and collected data from before and after antifouling additive, that could find the membrane fouling and clogging results of the influent raw water. Obviously, the influent raw water quality into LPRO membrane is closely connected to the efficiency of treatment plant. The results show when the temperature decreased of influent raw water that could decrease the effluent volume from LPRO, because the water temperature affected by increase viscosity of raw water. The first part clogging substances of membrane were aluminum (Al), that could be use aluminate coagulant to make increase more aluminum. And the TOC value of the effluent were from 0.2 to 1.4 mg/L, that shows the effluent water was kept stably but UV254 value were have more than 75% efficiency. Results of organic analysis on LPRO effluent indicates the pretreatment process could leave annular structure organic. In other hand, when using EEFM to analysis the spectra sampling of organic of LPRO, there finding a lot low emission wavelength fluoresces of influent on EX/EM 230/340 and decrease the wavelength fluoresces value on EX/EM 280/330 and 240/340 by RO membrane system of LPRO. To be worth mentioning, when organism of sampling fluoresces value during high emission wavelength on EX/EM 240/400 nm was disappeared, that indicates RO membrane has good performance to separation organism of water. And results of elements analysis on RO membrane surface were using SEM and EDX have a lot aluminum and silicate on segment RO membrane module. Therefore, results show pretreatment process of coagulation and sedimentation could not treatment metal substances and organic efficiency, that was to effect directly cause to make the problems of membrane fouling and clogging.
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Application and evaluation of UF and RO membraneSu, Huan-Shen 30 June 2011 (has links)
Currently influence of water quality of water resource is greatly affected typhoon and rainstorm caused by climate change. Additional factors are including over cut trees, soil-rock flood and bad conservation of water-soil in hillside. Thus many researchers used ¡§membrane technology ¡§to remove pollutants such as suspended solids, alga, heavy metals and organic toxics.
This work is studying performance of advanced water treatment processes using UF and LPRO membranes in a plant (noted as plant A). During the period of research; we analyzed items such as turbidity, TOC and hardness and operation parameters to investigate the efficiency of UF and LPRO.
Results showed the traditional treatment processes has not effective removal on TOC, Fe ions ,Mn ions and hardness in raw water in plant A. But the removal efficiency was over 80% by using the later treatment of UF/RO. When plant A operated at good control and well detergent-wash, the life of UF/RO system is longer.
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Atividade do interferon tipo I suíno na proteção contra o vírus da febre aftosa (FMDV) / Activity of swine type i interferon in protection against foot-and-mouth disease virus (FMDV)Botton, Sonia de Avila 08 March 2005 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this study is to evaluate the adjuvant effect of interferon alpha (IFNα) in swine vaccinated with a recombinant replication-defective adenovirus containing foot-and-mouth disease virus (FMDV) protein coding regions, as well as to understand the molecular mechanisms involved in the interaction of FMDV with its host. In the first part of this thesis, the adjuvant effect of pIFNα was evaluated in swine vaccinated with a recombinant vaccine delivered by a human adenovirus type 5 (Ad5) vector containing FMDV capsid (P1-2A) and 3Cpro proteinase coding regions (Ad5-A24). Swine were separated into 5 groups and inoculated with low (5x108 PFU) or high (5x109 PFU) doses of Ad5-A24 in the presence or absence of pIFNα (Ad5-pIFN, 109 PFU). Control animals received 6x109 PFU of an Ad5 vector containing the glycoprotein gene of vesicular stomatitis virus (Ad5-VSNJV-G). All swine were challenged at 42 days post vaccination (dpv) with FMDV-A24. Prior to challenge, blood samples were examined for IFN production, induction of IFN-induced genes (ISG s), FMDV-specific neutralizing antibodies and FMDV-specific antibody isotypes. After challenge, a number of parameters were analyzed including clinical score, viremia, lymphopenia and antibodies against FMDV structural (S) and non-structural (NS) proteins. The results indicate that both groups that received high-dose Ad5-A24 developed an FMDV-specific neutralizing antibody response by 14-21 dpv, which was maintained until the day of challenge. Both high-dose groups developed high levels of IgG1 and IgG2, however the IgG1 response was higher. The high-dose Ad5-A24 with IFN group developed higher levels of IgG1 than the group administered only high-dose Ad5-A24 and this difference was statistically significant. Antiviral activity and IFNα were detected in the groups that received IFN. The three ISG s examined, PKR, OAS and Mx1, were detected by real time RT-PCR in leukocytes from Ad5-pIFNα-vaccinated swine. After challenge, all animals in the control group developed early viremia, vesicular lesions, considerable lymphopenia and antibodies to FMDV NS proteins. The animals that received low-dose Ad5-A24 without IFN had similar clinical signs, except that fewer animals had viremia. In contrast, pigs inoculated with the low-dose Ad5-A24 and IFNα had a delayed onset of vesicular lesions and only one animal had detectable viremia. Animals vaccinated with high-dose Ad5-A24 without IFNα had no viremia, showed fewer lesions, one animal had no lesions, and delayed onset of disease compared to the low-dose Ad5-A24 groups. Four of five pigs vaccinated with high-dose Ad5-A24 and IFNα were completely protected from disease and only one animal in this group had a vesicular lesion restricted to the site of challenge virus inoculation. The results indicate that IFNα enhances the level of protection induced by the Ad5-FMD vaccine against homologous FMDV, supporting the use of IFNα as a potential adjuvant in FMD vaccination strategies. To investigate the effect of FMDV infection on the induction of the host IFN-α/β response, swine cells were infected with wild-type (WT) FMDV and a mutant FMDV lacking the L proteinase (Lpro) coding region (A12-LLV) at different multiplicities of infection. The synthesis of IFN-α and IFN-β mRNAs and three well characterized ISG s, PKR, OAS, and Mx1 mRNA, were evaluated by real time RT-PCR. A12-LLV infection resulted in significantly higher levels of induction of IFN-β mRNA as compared to WT virus infected cells, while IFN-α mRNA was not induced after either infection. The increased levels of IFN-β mRNA in A12-LLV-infected cells correlated with higher levels of induction of PKR, OAS and Mx1 mRNAs and antiviral activity. By using RNA interference (RNAi) technology to knock-down PKR mRNA expression, it was possible to demonstrate that the yield of A12-LLV was increased up to 200-fold, supporting the role of PKR as an inhibitor of FMDV replication. These results confirm that Lpro down regulates the innate immune response to FMDV infection at multiple levels. Previous studies indicated that control was at the translation initiation level by Lpro cleavage of translation initiation factor eIF-4G. The present data demonstrates that regulation also occurs at the level of transcription by inhibition of IFN-β mRNA induction through an unknown mechanism. / Esse trabalho tem como objetivo avaliar o efeito adjuvante do interferon alfa suíno em animais imunizados com uma vacina recombinante de um adenovírus defectivo contendo as regiões codificadoras das proteínas do FMDV, bem como investigar alguns dos aspectos moleculares envolvidos na interação FMDV e a célula hospedeira em uma espécie susceptível. Na primeira fase do trabalho, o efeito adjuvante do interferon alfa suíno (pIFNα) foi avaliado em suínos imunizados com uma vacina recombinante, tendo como vetor o adenovirus humano tipo 5 (Ad5), contendo regiões do capsídeo do FMDV A24 e da proteinase 3Cpro do FMDV A12 (Ad5-A24). Os suínos foram separados em 5 grupos e inoculados com baixa (5x108 PFU) e alta (5x109 PFU) dosagem de Ad5-A24 na presença ou na ausência de pIFNα (Ad5pIFNα, 109 PFU). O grupo controle foi inoculado com 6x109 PFU da glicoproteína do vírus da estomatite vesicular (VSV) cepa New Jersey (Ad5VSNJV-G). Todos os suínos foram desafiados aos 42 dias pós-vacinação (dpv) com FMDV-A24. Após a inoculação, as amostras de sangue foram examinadas para a produção de IFN, a indução de genes induzidos pelo IFN e os anticorpos neutralizantes e resposta de imunoglobulinas específicos para o FMDV. Depois do desafio um número de parâmetros foram analisados incluindo a avaliação clínica, viremia, linfopenia; além dos anticorpos contra as proteínas estruturais e não estruturais do FMDV. Os resultados obtidos indicam que ambos os grupos que receberam Ad5-A24 em alta dosagem desenvolveram níveis de anticorpos neutralizantes pelos 14-21 dpv, que foram mantidos até o dia do desafio. Os níveis de IgG1 foram maiores que de IgG2 nesses dois grupos, sendo que a IgG1 é considerada a mais relevante para conferir proteção ao FMDV. Dentre esses grupos, o que recebeu o IFN apresentou níveis significativamente mais altos desta imunoglobulina. Atividade antiviral e o IFNα foram detectados nos animais que receberam o IFN. A respeito da presença dos genes induzidos pelo IFN nos leucócitos dos suínos vacinados com Ad5-pIFNα, todos os três genes incluídos neste estudo, PKR, OAS e Mx1, foram detectados pelo real time RT-PCR. Após o desafio todos os animais do controle desenvolveram viremia, linfopenia, lesões vesiculares e os anticorpos contra as proteínas não estruturais do FMDV. Os animais que receberam baixa dose de Ad5-A24 sem IFN tiveram sinais clínicos similares, exceto que poucos animais desenvolveram viremia. Porém, os suínos inoculados com a mesma dose da vacina de Ad5-A24 com o IFN apresentaram as lesões vesiculares com início tardio e somente um animal teve detectável viremia. Os animais vacinados com a alta dose de Ad5-A24 sem IFN não tiveram nenhuma viremia e poucas lesões foram detectadas tardiamente após a inoculação do FMDV. Quatro dos cinco suínos, que receberam a alta dose da vacina com o IFN, foram protegidos da doença e somente um animal neste grupo teve uma lesão vesicular, restrita ao local do inoculação do vírus por ocasião do desafio. Esses resultados indicam que IFNα realça o nível da proteção induzido pela vacina do adenovírus-FMD contra o FMDV homólogo, suportando o uso do IFNα como um adjuvante potencial em estratégias de vacinação de FMD. Para avaliar os efeitos da infecção pelo vírus da FMD na indução da resposta de IFNα⁄β do hospedeiro, células de origem suína foram previamente infectadas em diferentes multiplicidades de infecção com o FMDV e com um vírus mutante que teve o gene que codifica a protease L ou Lpro deletado, o FMDLLV. A síntese de mRNA do IFNα e β bem como de três dos genes induzidos pelo IFN, PKR, OAS e Mx1 foram avaliados por real time RT-PCR. A infecção das células pelo FMDLLV induziu altos níveis de mRNA do IFNβ quando comparados com os do FMDV original. Contudo, não foi possível detectar os níveis de mRNA do IFNα na presença de ambos os vírus. O aumento nos níveis de mRNA do IFNβ foi relacionado ao aumento nos níveis de indução dos mRNAs de PKR, OAS e Mx1, assim como dos altos níveis de atividade antiviral. Pelo uso da tecnologia de interferência do RNA, usando siRNA (silencing RNA) para bloquear a expressão do mRNA da PKR, foi possível demonstrar que o título do FMDLLV aumentou cerca de 200 vezes. Desta forma foi possível confirmar o papel desta proteína como um inibidor da replicação do FMDV. Os resultados obtidos demonstram que a Lpro tem um importante papel na regulação da resposta imunológica inata do hospedeiro quando da infecção pelo FMDV em vários níveis. Estudos anteriormente realizados indicaram que o controle era efetuado ao nível da tradução pela clivagem do eIF4G. Os dados obtidos neste trabalho indicam que a regulação também ocorre ao nível da transcrição e pela inibição da indução do IFNβ através de um mecanismo ainda não conhecido.
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