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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Production, Purification, and Characterization of wood substrates and Galactose oxidase enzyme / Produktion, rening och karakterisering av träsubstrat och galaktosoxidasenzym

Pongalikonnar Ranganathan, Rakhesh January 2023 (has links)
Trä är den bästa förnyelsebara källan för att producera många produkter på grund av dess biokompatibla och biologiskt nedbrytbara natur. Träets biomassa har en motstridig natur mot enzymatisk uppgradering. Det beror på olika orsaker som ligninhalt, acetylhalt i hemicellulosa och cellulosakristallinitet som blockerar enzymets bindningsställe. Denna studie kommer under BioUPGRADE, som är en samarbetsplattform för att skapa högvärdiga och mångsidiga material på ett hållbart sätt med hjälp av biokatalys. Det allmänna syftet med denna studie är att producera holocellulosa och hemicellulosasubstrat från olika träslag och producera, rena och validera galaktosoxidas som en potentiell biokatalysator för träfibermodifiering. Studien undersöker effekten av kemisk perättiksyradelignifiering på två träslag, lövträ av eukalyptus (HW), och barrträ av gran (SW), undersökta vid olika tidsintervall, där PAA framställdes exsitu med ett volymetriskt förhållande på 1:3. Med resultaten från PAA-behandlingen avlägsnades 38,53 % lignin i eukalyptus och 31,80 % i barrved. Hemicellulosautbytet ökade med 47,40 % för eukalyptus och 19,05 % för gran med en ökning av tiden för PAA-behandling. Acetylhalten i hemicellulosan minskade från 2 % till 0,6 % i lövträ och 1,96 % till 0,6 % i barrträ. Cellulosautvinningen efter delignifieringen var nästan 100 %. Galaktosoxidaset producerades i en skakkolv med användning av Pichia pastoris KM71H-stammen. Pichia pastoris KM71H-celler odlades med användning av det buffrade komplexa glycerolmediet (BMGY) och galaktosoxidas uttrycktes med användning av Pichia pastoris KM71H-stammen i buffrat komplex metanolmedium (BMMY). Det uttryckta GaOx-proteinet renades därefter med användning av AKTA-kromatografi med användning av en 5 ml Histrap FF-kolonn. För att bestämma proteinkoncentrationen utfördes bicinchoninsyra (BCA) analys och GaOx som producerades i skakkolvsodling var 286,25 mg/L. Den specifika aktiviteten hos skakkolven som produceras GaOx är 164,24 U/mg. Det kan observeras att PAA-behandling visar sig vara en effektiv metod för delignifiering eftersom cellulosautvinningen är nära 100 % och förlusten av hemicellulosa är relativt låg med det använda volymetriska förhållandet. GaOx som produceras i skakkolvsproduktion visar ett lovande utbyte med en betydande specifik aktivitet mot galaktosen som substrat och kan användas i framtiden för enzymatisk uppgradering av träets biomassa. / Wood is the best renewable source for producing many products due to its biocompatible and biodegradable nature. The wood biomass has a recalcitrance nature towards enzymatic upgrading. It is due to various reasons such as lignin content, acetyl content in hemicellulose, and cellulose crystallinity which blocks the enzyme binding site. This study comes under BioUPGRADE, which is a collaborative platform to create high-value and multipurpose materials sustainably using biocatalysis. The general aim of this study is to produce holocellulose and hemicellulose substrates from different wood species and produce, purify, and validate galactose oxidase as a potential biocatalyst for wood fiber modification. The study investigates the effect of chemical peracetic acid delignification on two wood species, eucalyptus hardwood (HW), and spruce softwood (SW) investigated at different time intervals, where the PAA was prepared ex-situ with a volumetric ratio of 1:3. With the results from the PAA treatment, 38.53% of lignin was removed in eucalyptus and 31.80% in softwood. The hemicellulose yield increased by 47.40% for eucalyptus and 19.05% for spruce with an increase in the time of PAA treatment. The acetyl content of the hemicellulose was reduced from 2% to 0.6% in hardwood and 1.96% to 0.6% in softwood. The cellulose recovery after the delignification was nearly 100%. The galactose oxidase was produced in a shake flask using the Pichia pastoris KM71H strain. Pichia pastoris KM71H cells were cultivated using the buffered complex glycerol media (BMGY) and galactose oxidase was expressed using the Pichia pastoris KM71H strain in Buffered complex methanol media (BMMY). The expressed GaOx protein was subsequently purified using AKTA chromatography using a 5ml Histrap FF column. To determine the protein concentration Bicinchoninic acid (BCA) analysis was performed and the GaOx produced in shake flask cultivation was 286.25 mg/L. The specific activity of the shake flask produced GaOx is 164.24 U/mg. It can be observed that PAA treatment proves to be an efficient method for delignification as the cellulose recovery is near 100% and the loss of hemicellulose is relatively low with the volumetric ratio used. The GaOx produced in shake flask production shows a promising yield with a significant specific activity towards the galactose as substrate and could be used in the future for the enzymatic upgrading of the wood biomass.
62

Chemische und physikalische Verfahren zur Inaktivierung von pathogenen Mikroorganismen in allogenen Knochentransplantaten

Pruß, Axel 12 November 2004 (has links)
In allogeneic bone transplantation, the transmission of viral and non-viral infectious pathogens is the most severe undesirable concomitant phenomenon. The investigations published were examined regarding the inactivating capacity of inactivation procedures that are presently performed in bone banks (peracetic acid/ethanol, gamma irradiation, moist heat) against clinically relevant pathogens (aiming at a virus titer reduction of at least 4 log10 TCID50/ml or titer reduction of non-viral micro-organisms of at least 5 log10 cfu/ml). In the suspension experiments, treatment with peracetic acid/ethanol (peracetic acid 2%, ethanol 96%, aqua ad iniectabilia 2:1:1, 4 hours, 200 mbar, agitation) achieved a titer reduction of > 4 log10 already after 5 minutes for a number of viruses (PSR, PV, BVDV). HIV-2 was also inactivated within 5 minutes below the level of detection ( 4 log10 TCID50/ml was only reached after 4 hours. The results mentioned could be confirmed in the carrier test (contaminated spongiosa cuboids used as ‘worst case’ scenario). In the suspension experiment as well as in the carrier test, the HAV titer was reduced after 4 hours by only 3.7 log10 and 2.87 log10, respectively. The preceding step of defatting the spongiosa tissue by chloroform/ethanol was validated using cell-associated HAV and showed an HAV titer reduction of 7 log10. In the investigations regarding non-viral pathogens, all test organisms were completely inactivated by more than 5 log 10 steps (cfu/ml). Gamma irradiation was the second procedure examined. D10 values (irradiation dose required to reduce 90% of the pathogen titers by one log10 step) that were determined in inactivation kinetics experiments (irradiation conditions: –30°C, 60Co source) corresponded to data published so far. In order to provide for maximal safety, an irradiation dose of 34 kGy was recommended for allogeneic bone transplants using BPV and a diaphysis model from human femurs. The ‘Marburg bone bank system’ was the third procedure examined (thermal disinfection, guaranteed temperature of at least 82.5°C for a minimum of 15 min) using centrally contaminated human femoral heads. All viruses were completely inactivated and their titer reduced by more than 4 log10 steps. Vegetative bacteria and fungi were also completely inactivated (>= 6 log10 in the supernatant). As expected, spores and spore-forming pathogens were not sufficiently inactivated and not inactivated, respectively (titer reduction of less than 2 log10 cfu/ml). However, the latter group can be disregarded, since femoral heads are procured in the operation room under sterile conditions and the following production process rules out a secondary contamination with spores. It could be shown in the investigations presented that all three procedures examined guarantee an inactivation of the viruses investigated according to the recommendations by the senior federal authorities. The three treatment procedures offer additional biosafety by a comprehensive inactivation of non-viral pathogens.
63

O impacto de reúso de dialisadores nos marcadores de estresse oxidativo e inflamatórios em pacientes em hemodiálise / Evaluation of oxidative stress and inflamatory markers on hemodialysis patients with and without dialysers reuse

Furlan, Carla Barbosa Muraro 27 March 2014 (has links)
A morbimortalidade dos pacientes em hemodiálise permanece alta apesar da evolução tecnológica do procedimento, sendo que os eventos cardiovasculares são a sua principal causa. Estes desencadeados pela alta prevalência de fatores de risco tradicionais, fatores relacionados ao procedimento dialítico e estresse oxidativo. Considerando o procedimento dialítico e o estresse oxidativo, foi avaliado o quanto a habitual prática de reuso de dialisadores/RD (difundida nas Américas e amparada principalmente por questões econômicas) e uso único de dialisadores, influenciam nos marcadores inflamatórios e de estresse oxidativo. Para isto, foram utilizados como marcadores laboratoriais as medidas de PCR ultrassensível (u PCR), interleucina 6 (IL6), a determinação de substâncias reativas ao ácido tiobarbitúrico (TBARS), superóxido dismutase (SOD), glutationa (GSH) e albumina, em 29 pacientes em tratamento de hemodiálise. Estes pacientes encontravam-se em tratamento com dialisadores de alto fluxo do tipo polieterssulfona e reuso manual, e ao iniciar este estudo foram programados 3 ciclos sequenciais com duração de 6 semanas com as seguintes características: primeiro ciclo (uso único de dialisadores;); segundo ciclo (reuso de dialisadores); terceiro ciclo (reuso de dialisadores e administração de N-acetilcisteína/NAC, na dose de 1200 mg/dia). Foram coletadas amostras de sangue de cada paciente no início e final da última sessão de hemodiálise anteriormente ao início dos ciclos (denominado Período 1) e no início e final da última sessão de hemodiálise de cada ciclo (denominados Períodos 2, 3 e 4 respectivamente). O TBARS aumentou no período de uso único. Todas as demais variáveis não apresentaram diferença significativa. Os resultados indicaram que o RD pode proporcionar uma melhora no estresse oxidativo. O uso único foi associado com maior estresse oxidativo. Não foi encontrado nenhum benefício adicional com NAC / The morbidity and mortality of patients undergoing hemodialysis remains high despite the technological development of this procedure, and cardiovascular events are the main causes of morbidity and mortality. These cardiovascular events are triggered by the high prevalence of traditional risk factors, factors associated with dialysis procedures, and oxidative stress. Considering the factors associated with dialysis procedures and oxidative stress, we assessed how dialyzer reuse (DR; widespread in the Americas, especially because of economic issues) and use of single-use dialyzers influence oxidative stress and inflammatory markers. We used ultrasensitive PCR (u-PCR) to measure levels of the laboratory markers interleukin-6 (IL6), thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), glutathione (GSH), and albumin in 29 patients undergoing hemodialysis treatment. These patients were receiving treatment with polyethersulfone high-flux dialyzers and manual reuse. In the initial phase of this study, the 3 following sequential cycles, each lasting 6 weeks, were scheduled: first cycle (single-use dialyzers); second cycle (DR); and third cycle (DR and administration of N-acetylcysteine [NAC] at a dose of 1200 mg/day). Blood samples were collected from each patient at the beginning and end of the last hemodialysis session that preceded the start of the cycles (termed Period 1), and at the beginning and end of the last hemodialysis session of each cycle (termed Periods 2, 3, and 4, respectively). The levels of TBARS increased during the single-use period. The remaining variables did not show significant differences. The results indicated that DR may ameliorate oxidative stress. Single-use dialyzers were associated with higher oxidative stress. No additional benefit was found with use of NAC
64

Eliminación del Biofouling en intercambiadores de calor-condensadores que minimicen el impacto ambiental en el medio marino

Río Calonge, Belén 28 September 1999 (has links)
La presente tesis doctoral tiene por objeto tratar de eliminar el fenómeno no deseable de formación de biofouling en diferentes superficies tubulares de intercambiadores de calor, mediante tratamientos físicos y químicos, intentando minimizar el impacto ambiental creado en los efluentes de las instalaciones industriales.El equipo experimental está compuesto por una planta piloto de intercambiadores de calor condensadores dotada de ocho tubos que funcionan como sistemas independientes, donde se controlan los parámetros de presión, temperatura y caudal, que define indirectamente el biofouling depositado en el interior de dichos tubos a través de los valores de resistencia friccional al flujo y resistencia a la transferencia de calor.También ha sido diseñado y construido otra planta piloto o monitor "MCMDID" (monitor combinado de medición directa e indirecta del biofouling) donde se mide en continuo el espesor del biofouling adherido a la superficie de un tubo del mismo material que los ensayados en la planta descrita anteriormente.
65

EFEITO DA IMERSÃO PERIÓDICA EM SOLUÇÕES LIMPADORAS NA RUGOSIDADE SUPERFICIAL, PORCENTAGEM DE VARIAÇÃO DE MASSA E RESISTÊNCIA FLEXURAL DE LIGAS DE COBALTO-CROMO / Co-Cr ALLOY IMMERSION IN CLEANING SOLUTIONS: EFFECTS ON FLEXURAL STRENGTH, SURFACE ROUGHNESS AND PERCENTUAL OF VARIATION OF MASS

Borsa, Pedro Carlos Cortiana 22 August 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate the flexural strength, elastic modulus, mass changes and surface roughness of two cobalt-chromium alloys, before and after immersions in four cleaning solutions and distilled water (as control). Co-Cr alloys (Co-Cr®, Dentsply-DeguDent Industria e Comércio, São Paulo, Brasil; and GM 800+®, Dentaurum GmbH & Co KG, Ispringen, Alemanha) were investigated. Fifty bar specimens (25 x 3 x 0,5 mm) for the flexural test, 50 quadrangular specimens (10 x 10 x 1 mm) for mass changes evaluation and 35 cylindrical specimens (10 x 1 mm) for surface roughness measurements were obtained by casting. They were polished by abrasive paper (#240 to #2500) and diamond polishing paste (3μm). Specimens were randomly divided into 5 groups according the following cleaning, solutions: pure white vinegar, 0.2% peracetic acid, sodium perborate - Corega Tabs®, 0.37% sodium hypochlorite and the control, distilled water. Surface roughness (Ra parameter) was analyzed using a profilometer (Mitutoyo SJ 410, Mitutoyo Corp, Kanagawa, Japan) before and after 5, 20 e 90 immersions (10 min each). Ra changes (ΔRa5, ΔRa20 e ΔRa90) were calculated for the different intervals. Qualitative surface analyses were performed by Scanning Electron Microscope (JSM 6360 SEM, JEOL). Both alloys, immersed in pure white vinegar, 0.2% peracetic acid, sodium perborate - Corega Tabs®, 0.37% sodium hypochlorite had similar roughness changes after 90 immersions (ΔRa from -0,012 to 0,022 μm). There was a significant surface roughening in hypochlorite (ΔRa90= 0,064 μm for CoCr®; and ΔRa90 = 0,592 μm for GM 800+). The number of immersions influenced on the roughness changes only in hypochlorite and there were greater changes in the GM 800+ alloy. After 90 immersions, GM 800+ alloy showed mass lost in the hypochlorite solution (-0,3%). This alloy presented higher flexural strength after 90 immersions in SH (σF= 1516 MPa in hypochlorite; 1366 MPa in control). However, there were no elastic modulus changes. CoCr® alloy did not present differences in the σF or in elastic modulus in any solution. The only solution that damaged the alloy surface was 0.37% sodium hypochlorite. / O objetivo deste trabalho foi avaliar a rugosidade superficial,o percentual de variação de massa, a resistência flexural e o módulo de elasticidade de duas ligas de Cobalto-Cromo após submetidas à imersões em quatro soluções limpadoras e água (controle). Foram utilizadas as ligas Co-Cr® DeguDent (Dentsply-DeguDent Industria e Comércio, São Paulo, Brasil) e Remanium® GM 800+ (Dentaurum GmbH & Co KG, Ispringen, Alemanha). De cada liga fundiu-se cinquenta corpos de prova, 50 cilíndricos (10 x 1 mm) para a análise da rugosidade, 50 quadrangulares (10 x 10 x 1 mm) para avaliação da variação de massa e em formato retangular (25 x 2,5 x 0,75 mm) para o teste flexão 3 pontos. O polimento se deu por seqüencia de lixas (#400 a 2500) e pasta diamantada (3μm). A distribuição aleatória foi em 5 grupos, conforme os agentes de limpeza: vinagre branco puro, ácido peracético 0,2% , perborato de sódio (Corega Tabs®), hipoclorito de sódio 0,37% e o controle: água destilada. Foram realizadas avaliações da rugosidade superficial (Parâmetro Ra) através de rugosímetro (Mitutoyo SJ 410, Mitutoyo Corp, Kanagawa, Japan) antes e após 5, 20 e 90 ciclos de imersão de 10 minutos. As alterações de Ra (ΔRa5, ΔRa20 e ΔRa90) foram calculadas entre os diferentes interrupções. Análise complementar da superfície foi realizada em imagens obtidas por microscopia eletrônica de varredura (JSM 6360 SEM, JEOL Ltd., Tokyo, Japan). A pesagens dos corpos de prova para cálculo da variação de massa se deu após 5 e 90 imersões, utilizando-se de balança eletrônica analítica com sensibilidade de 0,0001 g (FA 2004, Coleman E. P. L. Com. e Imp. Ltda. Santo André, São Paulo). Os ensaios de flexão a 3 pontos para determinação da resistência flexural (σF) e do módulo de elasticidade foram realizados após 90 imersões. Os dados obtitos foram analisados quanto a normalidade e testes de comparação entre médias foram aplicados conforme o tipo de distribuição. As duas ligas, imersas nas soluções vinagre puro, ácido peracético, corega tabs® apresentaram comportamento semelhante em relação as alterações de rugosidade superficial (Ra), quando comparadas ao controle, após 90 imersões (ΔRa entre -0,012 e 0,022 μm). Aumento da rugosidade significativo ocorreu na solução de hipoclorito (ΔRa90= 0,064 μm (CoCr®) e 0,592 μm (GM 800+). O número de imersões influenciou na variação de rugosidade, apenas para a solução de hipoclorito, sendo que as maiores variações ocorreram na liga GM 800+. Após 90 imersões a liga GM 800+ demonstrou perda de massa na solução de hipoclorito (-0,3%). Ocorrendo para essa liga aumento da resistência flexural (σF= 1516 MPa em hipoclorito; 1366 MPa no controle) após 90 imersões, sem modificação de seu módulo de elasticidade. A liga CoCr® não apresentou diferenças na σF ou no módulo de elasticidade nas diferentes soluções. A única solução que causou dano à superfície das ligas foi o hipoclorito de sódio 0,37%.
66

O impacto de reúso de dialisadores nos marcadores de estresse oxidativo e inflamatórios em pacientes em hemodiálise / Evaluation of oxidative stress and inflamatory markers on hemodialysis patients with and without dialysers reuse

Carla Barbosa Muraro Furlan 27 March 2014 (has links)
A morbimortalidade dos pacientes em hemodiálise permanece alta apesar da evolução tecnológica do procedimento, sendo que os eventos cardiovasculares são a sua principal causa. Estes desencadeados pela alta prevalência de fatores de risco tradicionais, fatores relacionados ao procedimento dialítico e estresse oxidativo. Considerando o procedimento dialítico e o estresse oxidativo, foi avaliado o quanto a habitual prática de reuso de dialisadores/RD (difundida nas Américas e amparada principalmente por questões econômicas) e uso único de dialisadores, influenciam nos marcadores inflamatórios e de estresse oxidativo. Para isto, foram utilizados como marcadores laboratoriais as medidas de PCR ultrassensível (u PCR), interleucina 6 (IL6), a determinação de substâncias reativas ao ácido tiobarbitúrico (TBARS), superóxido dismutase (SOD), glutationa (GSH) e albumina, em 29 pacientes em tratamento de hemodiálise. Estes pacientes encontravam-se em tratamento com dialisadores de alto fluxo do tipo polieterssulfona e reuso manual, e ao iniciar este estudo foram programados 3 ciclos sequenciais com duração de 6 semanas com as seguintes características: primeiro ciclo (uso único de dialisadores;); segundo ciclo (reuso de dialisadores); terceiro ciclo (reuso de dialisadores e administração de N-acetilcisteína/NAC, na dose de 1200 mg/dia). Foram coletadas amostras de sangue de cada paciente no início e final da última sessão de hemodiálise anteriormente ao início dos ciclos (denominado Período 1) e no início e final da última sessão de hemodiálise de cada ciclo (denominados Períodos 2, 3 e 4 respectivamente). O TBARS aumentou no período de uso único. Todas as demais variáveis não apresentaram diferença significativa. Os resultados indicaram que o RD pode proporcionar uma melhora no estresse oxidativo. O uso único foi associado com maior estresse oxidativo. Não foi encontrado nenhum benefício adicional com NAC / The morbidity and mortality of patients undergoing hemodialysis remains high despite the technological development of this procedure, and cardiovascular events are the main causes of morbidity and mortality. These cardiovascular events are triggered by the high prevalence of traditional risk factors, factors associated with dialysis procedures, and oxidative stress. Considering the factors associated with dialysis procedures and oxidative stress, we assessed how dialyzer reuse (DR; widespread in the Americas, especially because of economic issues) and use of single-use dialyzers influence oxidative stress and inflammatory markers. We used ultrasensitive PCR (u-PCR) to measure levels of the laboratory markers interleukin-6 (IL6), thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), glutathione (GSH), and albumin in 29 patients undergoing hemodialysis treatment. These patients were receiving treatment with polyethersulfone high-flux dialyzers and manual reuse. In the initial phase of this study, the 3 following sequential cycles, each lasting 6 weeks, were scheduled: first cycle (single-use dialyzers); second cycle (DR); and third cycle (DR and administration of N-acetylcysteine [NAC] at a dose of 1200 mg/day). Blood samples were collected from each patient at the beginning and end of the last hemodialysis session that preceded the start of the cycles (termed Period 1), and at the beginning and end of the last hemodialysis session of each cycle (termed Periods 2, 3, and 4, respectively). The levels of TBARS increased during the single-use period. The remaining variables did not show significant differences. The results indicated that DR may ameliorate oxidative stress. Single-use dialyzers were associated with higher oxidative stress. No additional benefit was found with use of NAC
67

New adsorption and oxidation-based approaches for water and wastewater treatment:studies regarding organic peracids, boiler-water treatment, and geopolymers

Luukkonen, T. (Tero) 12 January 2016 (has links)
Abstract This thesis examines three different areas of water treatment technology: the application of organic peracids in wastewater treatment; the removal of organic residues from boiler make-up water; and the use of geopolymers as sorbents. The main advantages of peracids as alternative wastewater disinfectants are their effective antimicrobial properties and high oxidation power, as well the absence of harmful disinfection by-products after their use. Performic, peracetic and perpropionic acids were compared in laboratory-scale disinfection, oxidation and corrosion experiments. From the techno-economical point of view, performic acid proved to be the most effective disinfectant against E. coli and fecal enterococci. However, in the bisphenol-A oxidation experiments, no advantages compared to hydrogen peroxide use were observed. It was also determined that corrosion rates on stainless steel 316L were negligible, while carbon steel seemed unsuitable in terms of corrosion for use with peracids even in low concentrations. Organic compounds in the boiler plant water-steam cycle thermally decompose and form potentially corrosive species. Activated carbon filtration was confirmed to be a suitable method for the removal of organic residue from deionized boiler make-up water. No significant differences in terms of treatment efficiency between commercial activated carbons were observed. However, acid washing as a pre-treatment reduced the leaching of impurities from new carbon beds. Nevertheless, a mixed-bed ion exchanger was required to remove leached impurities, such as silica and sodium. Geopolymers, or amorphous analogues of zeolites, can be used as sorbents in the treatment of wastewater. Metakaolin and blast-furnace-slag geopolymers showed positive potential in the treatment of landfill leachate (NH4+ ) and mine effluent (Ni, As, Sb). / Tiivistelmä Tämä väitöskirja käsittelee kolmea erillistä vedenkäsittelyteknologian osa-aluetta: orgaanisten perhappojen käyttöä jäteveden käsittelyssä, orgaanisten jäämien poistoa suolavapaasta kattilalaitoksen lisävedestä ja geopolymeerien sovelluksia vedenkäsittelysorbentteina. Orgaanisten perhappojen pääasialliset edut verrattuna kilpaileviin tekniikoihin ovat hyvä desinfiointiteho, korkea hapetuspotentiaali ja desinfioinnin sivutuotteiden muodostumattomuus. Permuurahais-, peretikka- ja perpropaanihapon vertailu osoitti permuurahaishapon olevan kemikaaleista tehokkain E. coli - ja enterokokkibakteerien inaktivoinnissa kustannus- ja teknisistä näkökulmista. Hapetuksessa, jossa käytettiin bisfenoli-A:ta malliaineena, ei kuitenkaan havaittu etua verrattuna edullisempaan vetyperoksidiin. Ruostumattoman teräksen (316L) pinnalla ei havaittu merkittävää korroosiota, kun taas hiiliteräs ei sovellu käytettäväksi perhappojen kanssa. Orgaaniset jäämät kattilalaitoksen vesi-höyrykierrossa hajoavat termisesti pienen moolimassan hapoiksi ja aiheuttavat korroosioriskin. Aktiivihiilisuodatuksen todettiin olevan soveltuva menetelmä orgaanisten jäämien poistoon lisävedestä. Aktiivihiililaatujen välillä ei havaittu merkittäviä eroja, mutta happopesu aktiivihiilen esikäsittelynä vähensi hiilestä liukenevien epäpuhtauksien määrää. Geopolymeerit ovat zeoliittien amorfisia analogeja ja niiden ioninvaihtokykyä voidaan hyödyntää vedenkäsittelysovelluksissa. Metakaoliini- ja masuunikuonapohjaisten geopolymeerien todettiin olevan lupaavia materiaaleja malliliuosten, kaatopaikan suotoveden ja kaivoksen purkuveden käsittelyssä poistettaessa ammoniumia, nikkeliä, arseenia ja antimonia.

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