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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.
1

Efeitos da radiação UV-C na qualidade nutricional e tecnológica de grãos de milho inoculados com fungos e armazenados sob diferentes umidades / Effects of UV-C radiation on the nutritional and technological quality properties of corn inoculated with fungi and stored under different moisture.

Camargo, Cláudia Medeiros 31 July 2017 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-08-14T18:24:06Z No. of bitstreams: 1 Dissertação - Cláudia Medeiros Camargo.pdf: 1890787 bytes, checksum: 483a98199d1e25df032841b77b3a5358 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-08-17T12:37:05Z (GMT) No. of bitstreams: 1 Dissertação - Cláudia Medeiros Camargo.pdf: 1890787 bytes, checksum: 483a98199d1e25df032841b77b3a5358 (MD5) / Made available in DSpace on 2018-08-17T12:37:05Z (GMT). No. of bitstreams: 1 Dissertação - Cláudia Medeiros Camargo.pdf: 1890787 bytes, checksum: 483a98199d1e25df032841b77b3a5358 (MD5) Previous issue date: 2017-07-31 / Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS / O milho (Zea mays L.) ) é o segundo cereal mais produzido no Brasil e sua importância econômica se dá pelas diversas formas de uso e relevância na alimentação humana e animal. Devido à grande demanda de milho pela indústria alimentícia é necessário que os grãos fiquem armazenados por longos períodos para atender o mercado em períodos de entressafra. Durante o armazenamento, algumas espécies de fungos se proliferam em grãos armazenados favorecendo a produção de micotoxinas e tornando-os impróprios para o consumo. Dessa forma, a radiação pode ser um método alternativo de controle dos fungos e, portanto, manutenção da qualidade dos grãos de milho. Sendo assim, o trabalho foi dividido em dois capítulos visando atender a dois objetivos principais: i); ii) avaliar os efeitos da radiação UV-C e da umidade dos grãos nos parâmetros qualitativos e quantitativos tecnológicos dos grãos de milho durante o armazenamento; ii) avaliar os efeitos da radiação UV-C e da umidade dos grãos nos parâmetros qualitativos e quantitativos tecnológicos do amido de milho extraído de grãos armazenados durante o armazenamento. Foram utilizados grãos de milho colhidos mecanicamente e secos até as umidades de 13% e 16%. Os grãos receberam inóculos de fungos produtores de micotoxinas e tratamento com radiação UV-C nas doses de 4 e 8 Kj.m-2. A radiação UV-C nas doses utilizadas não apresentou influencia sobre os resultados obtidos, no entanto a umidade e o tempo de armazenamento influenciaram diretamente nos parâmetros avaliados. A associação de elevada umidade e armazenamento por longo prazo apresentou aumento sobre a incidência dos fungos Aspergillus e Pennicilium, condutividade elétrica, acidez lipídica, grãos mofados, ardidos e fermentados, e redução sobre os fungos do gênero Fusarium, solubilidade proteica, teor de lipídeos e valor L. Os compostos fenólicos apresentaram maior concentração nos grãos inoculados com fungos (0, 4 e 8 kJ.m- 2). As micotoxinas foram encontradas em maior concentração após o armazenamento, sendo favorecidas dose de 8 kJ.m-2 e a umidade de 16%. Não foram observadas alterações na amilose e solubilidade do amido. Após o armazenamento, na umidade de 16% são observadas as maiores alterações, com reduções na extração de amido, valor de L* e aumentos no valor b*, proteína bruta, teor de lipídeos. As propriedades de pasta foram mais influenciadas na umidade de 16%, com aumentos na temperatura de pasta, retrogradação e reduções na viscosidade máxima e viscosidade de quebra. O amido apresentou perfurações em todos os tratamentos, sendo encontradas em maiores concentrações na umidade de 16% na dose de 8kJ.m-2. A radiação promoveu aumento no poder de inchamento dos grânulos de amido em todas as doses em ambas as umidades, sendo os maior aumentos observados na umidade de 16%. / Corn (Zea mays L.) is the second most produced cereal in Brazil and its economic importance is due to the different forms of use and relevance in human and animal food. Because to the high demand of maize by the food industry, it is necessary that the grains are stored for long periods to meet the market in offseason. During storage, some species of fungi proliferate in stored grains favoring the production of mycotoxins and rendering them unfit for consumption. So, radiation can be an alternative method of fungus control and, therefore, maintenance of the quality of corn grains. Therefore, the study was divided into two chapters aimed at meeting two main objectives: i); Ii) to evaluate the effects of UV-C radiation and grain moisture on the qualitative and quantitative technological parameters of corn grains during nine months of storage; Ii) to evaluate the effects of UV-C radiation and grain moisture on the qualitative and quantitative technological parameters of corn starch extracted from grains stored during nine months of storage. Corn grains were harvested mechanically and dried to moisture of 13% and 16% . The grains were inoculated with fungi and treated with UV-C radiation at 4 and 8 KJ.m-2 doses. The UV-C radiation at the doses used did not influence the results obtained, however, moisture and storage time had a direct influence on the evaluated parameters. The association of high moisture and a long time of storage showed an increase in the incidence of fungi Aspergillus and Pennicilium, electrical conductivity, lipid acidity, moldy, arid and fermented grains, and reduction on fungi of the genre Fusarium, protein solubility, lipid content and Value L. The phenolic compounds presented higher concentration in the grains inoculated with fungi (0, 4 and 8 kJ.m-2). The mycotoxins were found in higher concentration after storage, being favored dose of 8 kJ.m-2 and the moisture of 16%. No changes were observed in the amylose and solubility of the starch. After storage, in the moiture of 16% are observed the major changes, with reductions in the extraction of starch, value of L * and increases in value b *, crude protein and lipid content. The pasta properties were most influenced at 16% moisture, with increases in pasta temperature, retrogradation and reductions in maximum viscosity and viscosity break. In all treatments, the starch presented perforations, being found in higher concentrations in the moisture of 16% and the dose of 8kJ.m-2. The radiation promoted an increase in the swelling power of the starch granules in all doses in both moistures, with the highest observed increases in moisture content of 16%.
2

Etude de microdécharges comme source de rayonnement ultraviolet intense / Study of microdischarges as a source of intense ultraviolet radiation

Martin, Virginie 08 December 2011 (has links)
La décontamination bactériologique des surfaces par lumière pulsée est un enjeu de société qui requiert le développement de nouveaux outils. Une technique ayant prouvée son efficacité est l’utilisation de lumière pulsée dans le domaine de longueur d’onde 200-280 nm (bande d’absorption de l’ADN). Dans ce travail, nous avons étudié deux sources, Décharge à Barrière Diélectrique (DBD) et réseaux de microdécharges permettant de générer un rayonnement à 222 nm correspondant à l’émission de l’exciplexe KrCl*. Nos études ont permis de démontrer qu’il était possible de produire des décharges dans de nombreuses microcavités fonctionnant en parallèle sans aucun ballast résistif à condition d’employer une excitation impulsionnelle nanoseconde. Des études d’imagerie et de spectroscopie résolues temporellement ont démontré que l’ensemble des microdécharges s’initiaient en moins de 5 ns, ce qui permet d’envisager la réalisation de matrice de microdécharges rayonnant des puissances crêtes élevées. Dans le cas des DBD, les études ont couplé modèle et expérience, ce qui nous a permis de déterminer les étapes clés de la cinétique réactionnelle et de prédire les meilleures conditions de production d’un rayonnement intense à 222 nm. Par ailleurs, grâce aux microdécharges, nous avons pu réaliser une source de rayonnement VUV permettant de sonder la densité de chlore atomique dans des réacteurs de gravure plasma par spectroscopie d'absorption résonnante. / Bacteriological decontamination of surfaces by pulsed light is a society issue that requires the development of new tools. A technique that proved its efficiency was to use a pulsed light in the 200-280 wavelength range corresponding to the DNA absorption band.In this work, we studied two different sources, the so-called Dielectric Barrier Discharge (DBD) and microdischarges arrays, to generate a radiation at 222 nm corresponding to the KrCl* exciplex emission. By using nanosecond pulsed discharges, we demonstrated that many microdischarges operating in parallel can be triggered simultaneously without introducing any resistive ballast. High speed ICCD imaging and time resolved spectroscopic studies had shown that all the microdischarges were initiated in less than 5 ns, which allowed the produce arrays of microdischarges generating high peak power of UV light. In the DBD case, studies have coupled experience and simulation which allowed us to determine the key steps of the kinetic pathways and to predict the best conditions for producing an intense 222 nm radiation. Moreover, microdischarges were also used to realize a VUV source to probe the atomic chlorine density in plasma etching reactors through resonance absorption spectroscopy.
3

Utilização de tratamentos físicos para o controle póscolheita de Cryptosporiopsis perennans em maçãs / Use of physical treatments for postharvest control of Cryptosporiopsis perennans on apples

Bartnicki, Vinícius Adão 28 May 2010 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-05T13:57:00Z No. of bitstreams: 1 PGPV10MA231.pdf: 289994 bytes, checksum: f6f6518eed8d4a3460fcad5b1cca7663 (MD5) / Made available in DSpace on 2018-03-05T13:57:00Z (GMT). No. of bitstreams: 1 PGPV10MA231.pdf: 289994 bytes, checksum: f6f6518eed8d4a3460fcad5b1cca7663 (MD5) Previous issue date: 2010-05-28 / Capes / Brazil is one of the main world producers of fruit, but much of the production is lost due to the high incidence of postharvest rots. The control with fungicides has been suffering restrictions by consumers and fruit importing countries. The benefits and viability of hot water spraying and UV-C radiation was shown in other countries and in Brazil to control rots caused by Botryosphaeria dothidea and Penicillium expansum on apples. This project aimed to assess the effect of heat treatment and/or UV-C radiation to control at postharvest bull’seye rot caused by Cryptosporiopsis perennans on apples, and to evaluate equipments for the implementation of these treatments. In the laboratory, the sensitivity of conidia of the pathogen to heat treatment was evaluated at temperatures of 28, 45, 50 and 55ºC, for 15 and 30 seconds, and to UV-C radiation at doses of 0.018 x 104, 0.037 x 104, 0.075 x 104, 0.150 x 104, 0.375 x 104, 0.750 x 104, 1.500 x 104 and 3.000 x 104 ergs mm-2. There was a reduction of more than 99% in the viability of conidia of C. perennans treated at or above 50°C for 15 seconds, and with UV-C radiation at doses 0.75 x 104 ergs mm-2. The combinations between heat treatment exposure time and UV-C radiation were also evaluated on apples inoculated with C. perennans in an experimental packing line. In this case, the spraying of hot water at 50°C for 15 seconds, and the treatment with UV-C radiation at the dose of 0.375 x 104 ergs mm-2, were effective in controlling the epiphytic population of C. perennans on 'Gala', 'Fuji' and 'Pink Lady' apples. Apples inoculated and naturally infected with the pathogen, after different periods of cold storage under controlled atmosphere (CA), were assessed for the effects of physical treatments to control bull's-eye rot in a commercial packing line. On 'Fuji' apples, stored for one, four and eight months under CA, and 'Gala', stored for five months under CA, the spraying of hot water at 50ºC for 12 seconds and/or treatment with UV-C radiation at 0.0069 x 104 ergs mm-2 reduced in more than 45% the incidence of bull's-eye rot. Therefore, the physical treatments tested reduced the postharvest losses on apples caused by bull’s-eye rot, providing competitiveness gain to the industry / O Brasil é um dos principais produtores mundiais de frutos, mas grande parte da produção é perdida devido à elevada incidência de podridões pós-colheita. O controle com fungicidas vem sofrendo restrições pelos consumidores e pelos países importadores de frutos. O benefício e a viabilidade do uso da aspersão do fruto com água aquecida e da radiação UV-C foi demonstrada no exterior e também no Brasil no controle de podridões em maçãs causadas por Penicillium expansum e Botryosphaeria dothidea. Este projeto visou determinar o efeito do tratamento térmico e/ou com radiação UV-C para o controle pós-colheita da podridão olho-de-boi em maçãs, causada por Cryptosporiopsis perennans, e avaliar equipamentos para a execução destes tratamentos. Em laboratório, foi avaliada a sensibilidade dos conídios do patógeno ao tratamento térmico nas temperaturas de 28, 45, 50 e 55ºC, por 15 e 30 segundos, e à radiação UV-C, nas doses de 0,018 x 104, 0,037 x 104, 0,075 x 104, 0,150 x 104, 0,375 x 104, 0,750 x 104, 1,500 x 104 e 3,000 x 104 ergs mm-2. Ocorreu redução superior a 99% na viabilidade dos conídios de C. perennans tratados com temperatura igual ou superior a 50ºC por 15 segundos, e com radiação UV-C na dose igual ou superior a 0,75 x 104 ergs mm-2. Posteriormente, foram avaliadas combinações de tempos de exposição ao tratamento térmico e à radiação UV-C em maçãs previamente inoculadas com C. perennans numa linha de seleção experimental. Neste caso, a aspersão de água aquecida, na temperatura de 50ºC por 15 segundos, e o tratamento com radiação UV-C, na dose de 0,375 x 104 ergs mm-2, mostraramse eficientes no controle da população epífita de C. perennans em maçãs 'Gala', 'Fuji' e 'Pink Lady'. Por fim, avaliou-se o efeito dos tratamentos, aplicados numa linha de seleção comercial, na incidência da podridão olho-de-boi em maçãs inoculadas e com infecção natural, com diferentes períodos de armazenamento em condição de atmosfera controlada (AC). Em maçãs 'Fuji' armazenadas por um, quatro e oito meses em AC, e 'Gala' armazenada por cinco meses em AC, o uso da aspersão de água aquecida a 50ºC durante 12 segundos e/ou da radiação UV-C na dose de 0,0069 x 104 ergs mm-2 reduziu em mais de 45% a incidência da podridão olho-de-boi. Assim, os tratamentos físicos testados reduzem as perdas pós-colheita ocasionadas pela podridão olho-de-boi em maçãs, proporcionando ao setor ganho em competitividade
4

Armazenamento, características físico-químicas e compostos bioativos em frutos de araçazeiro amarelo / STORAGE, PHYSICAL-CHEMICAL CHARACTERISTICS AND BIOATIVE COMPOUNDS IN YELLOW CHERRY GUAVA FRUITS

Acosta, Tâmara Foster 13 August 2018 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-10-08T18:22:00Z No. of bitstreams: 1 Dissertação Tâmara pronta.pdf: 1349844 bytes, checksum: 1430b80a9af0391718476567b946627e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-10-19T20:11:03Z (GMT) No. of bitstreams: 1 Dissertação Tâmara pronta.pdf: 1349844 bytes, checksum: 1430b80a9af0391718476567b946627e (MD5) / Made available in DSpace on 2018-10-19T20:11:03Z (GMT). No. of bitstreams: 1 Dissertação Tâmara pronta.pdf: 1349844 bytes, checksum: 1430b80a9af0391718476567b946627e (MD5) Previous issue date: 2018-08-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Com este trabalho objetivou-se de avaliar as características físico-químicas e fitoquímicas presentes nos frutos de 12 acessos de araçazeiro amarelo colhidos no Centro Agropecuário da Palma – UFPel. Com o interesse da população acerca de uma alimentação saudável, rica em frutas e hortaliças, e a crescente valorização de frutas nativas, justificou-se a busca por maiores conhecimentos acerca de Psidium cattleyanum L., espécie bastante comum em pomares domésticos e propriedades familiares no Rio Grande do Sul. O pomar experimental é oriundo de sementes retiradas de frutos de populações espontâneas coletados no sul do Rio Grande do Sul, e após três anos da implantação, foram selecionados 12 genótipos com características promissoras. As análises foram feitas no ciclo produtivo 2016/17 e repetidas no ciclo 2017/18, no quarto e quinto ano de produção, respectivamente. Procedeu-se a avaliação dos frutos produzidos pelas plantas selecionadas, onde em um primeiro momento foram avaliados diâmetro, altura e peso fresco, teores de sólidos solúveis, acidez titulável e pH; análises realizadas com os frutos frescos. No primeiro ciclo, os frutos de A15 e A36 mostraram-se superiores aos demais tratamentos quanto às características físico-químicas. No segundo ciclo, no mês que antecedeu a colheita, houve grande redução no volume pluviométrico, o que acabou reduzindo o tamanho e o peso fresco dos frutos. Ainda assim, o acesso A36 manteve-se acima da média nestas avaliações. Posteriormente foram avaliados os frutos previamente congelados quanto aos teores de carotenóides, compostos fenólicos e atividade antioxidante. Assim como ocorrido nas análises físico-químicas, houve diferença entre os ciclos para as características fitoquímicas devido à redução do regime pluviométrico. Os materiais A30, A35 e A06 apresentaram-se superiores para os teores de compostos fenólicos e carotenóides; porém, para atividade antioxidante, A06 obteve média significativamente inferior. Como avaliação complementar, no primeiro ano optou-se por avaliar também a vida útil dos frutos, submetendo-os à radiação UV-C e armazenamento refrigerado durante 12 dias. Considera-se que os acessos devem ser acompanhados por um maior número de ciclos, a fim de obter informações mais consistentes sobre os aspectos morfológicos e a composição dos frutos, pois as condições climatológicas influenciaram em suas características físico-químicas e fitoquímicas. / The objective of this work was to evaluate the physicochemical and phytochemical characteristics of the fruits of 12 genotypes of yellow guava fruits harvested at the Centro Agropecuário da Palma - UFPel. With the interest of the population about a healthy diet rich in fruits and vegetables, and the increasing appreciation of native fruits, it was justified the search for more knowledge about Psidium cattleyanum L., a species quite common in domestic orchards and family properties in the Rio Grande do Sul State. The experimental orchard comes from seeds collected from fruits of spontaneous populations collected in the south of Rio Grande do Sul State, and after three years of implantation, 12 genotypes with promising characteristics were selected. The analyzes were made in the 2016/17 production cycle and repeated in the 2017/18 cycle, in the fourth and fifth year of production, respectively. The fruits produced by the selected plants were evaluated, where at first they were evaluated diameter, height and fresh weight, soluble solids contents, titratable acidity and pH; analyzes performed with the fresh fruits. In the first cycle, the fruits of A15 and A36 were superior to the other treatments in relation to the physical-chemical characteristics. In the second cycle, in the month that preceded the harvest, there was a great reduction in the pluviometric volume, which ended up reducing the size and the fresh weight of the fruits. Nevertheless, A36 access remained above average in these assessments. Afterwards, the fruits previously frozen for carotenoid contents, phenolic compounds and antioxidant activity were evaluated. As occurred in the physical-chemical analyzes, there was a difference between cycles for the phytochemical characteristics due to the reduction of the pluviometric regime. Materials A30, A35 and A06 were higher for the contents of phenolic compounds and carotenoids; however, for antioxidant activity, A06 obtained significantly lower mean. As a complementary evaluation, in the first year it was also chosen to evaluate the useful life of the fruits, subjecting them to UV-C radiation and refrigerated storage for 12 days. It is considered that the accessions should be accompanied by a greater number of cycles, in order to obtain more consistent information about the morphological aspects and the composition of the fruits, since the climatic conditions influenced in their physico-chemical and phytochemical characteristics.
5

Utilisation du rayonnement UV-C comme méthode alternative aux produits chimiques dans la lutte et le contrôle de la prolifération des micro-organismes sur les matériaux du patrimoine / Use of UV-C radiation as an alternarive method to chemicals to combat the proliferation of microorganisms on heritage materials

Borderie, Fabien 14 November 2014 (has links)
L’objectif général de cette thèse est d’étudier et d’analyser l’effet du rayonnement UV-C comme méthodealternative aux produits chimiques dans la lutte et le contrôle de la prolifération des micro-organismesphotosynthétiques dans les grottes touristiques. Dans un premier temps, l’effet des UV-C a été analysé surdifférentes souches cavernicoles de micro-algues cultivées au laboratoire. Des analyses à l’échelle moléculaire,cellulaire et à l’échelle du biofilm d’algues ont permis de mettre en évidence un ensemble de dommages causépar l’irradiation aux UV-C (diminution de la viabilité et de l’activité photosynthétique, dégradation desmembranes, décoloration des cellules par destruction des pigments chlorophylliens, fragmentation de l’ADN,diminution de la surface d’occupation des biofilms d’algues cultivés sur support solide). Ceux-ci sont soit directs(réactions de photooxydation) soit indirects (liés à un stress oxydatif important). L’ensemble de ces résultats ontservi à la sélection de différentes durées d’exposition aux UV-C (traduites en doses d’UV-C) efficaces en termesd’éradication et de décoloration des micro-algues. Ces doses d’UV-C ont dans un deuxième temps été testées enconditions réelles sur le site d’étude de la grotte des Moidons (Jura, France). Une étude préalable à ces tests a étémenée afin de comprendre les dynamiques et les facteurs favorisant l’installation et la prolifération des biofilmsde micro-organismes photosynthétiques dans la grotte. L’étude des facteurs environnementaux mesurés àl’échelle du biofilm (quantité de lumière, type de support, localisation dans la grotte) ainsi que ceux mesurés àl’échelle de la cavité (circulation horizontale et verticale des eaux, vitesse des courants d’air, temps d’allumagedes lampes et temps de présence des visiteurs) ont permis de distinguer des zones de colonisation préférentielle.Plusieurs biofilms ont ensuite été sélectionnés pour tester l’efficacité des UV-C. Selon les caractéristiques desbiofilms (intensité de colonisation) et en fonction de leur emplacement dans la grotte (variations des facteurspréalablement déterminés), nous avons pu mettre en évidence une efficacité des UV-C variable dans le temps.Avec l’appui de résultats complémentaires obtenus sur deux souches de champignons et sur plusieurs types dematières picturales, l’ensemble des données collectées au cours de la thèse souligne l’intérêt et l’applicabilité destraitements aux UV-C dans divers contextes de conservation des matériaux du patrimoine / The aim of this thesis is to study and analyze the effect of UV-C radiation as an alternative method tochemicals to combat phototrophic microorganisms’ proliferation in show caves. First, the effect of UV-C wasanalyzed on several cave-dwelling unicellular green algae sub-cultured in laboratory conditions. Analysis at themolecular, cellular and biofilm scale highlighted several damages (decrease of viability and photosyntheticactivity, membrane degradation, chlorophyll bleaching, DNA fragmentation, decrease of the biofilms’ colonizedarea…) both direct (photooxydation reaction) or indirect (oxidative stress). These results helped to selectefficient UV-C exposure times (traduced in UV-C doses) both to eradicate and bleach green micro-algae.Second, these efficient UV-C doses were used to test the efficiency of UV-C treatments on natural phototrophicbiofilms proliferating in the Moidons Cave (Jura, France). Previous study to the UV-C tests was performed tounderstand the dynamics and factors that promote algal proliferation in this cave. Factors measured at the biofilmscale (quantity of light, type of the physical support, localization in the cave…) and at the cavity scale(horizontal and vertical circulation of waters, air currents, illumination time and visitors’ presence time) allowedto distinguish several preferential areas where growth-supporting conditions were present for algal proliferation.Then, several biofilms were selected to test the efficiency of UV-C treatments. According to the characteristicsof the biofilms (colonization intensity) and their localization in the cave (variations of the factors promotingcolonization) UV-C efficiency varied over time. Supplementary results obtained on filamentous fungi andmineral pigments used for prehistoric paintings, emphasize the interest and the applicability
6

Assessment of novel Advanced Oxidation Processes for the Simultaneous Disinfection and Decontamination of Water

Berruti, Ilaria 30 May 2022 (has links)
[ES] El mundo se enfrenta a una profunda crisis asociada al agua y la reutilización de aguas residuales urbanas (UWW), especialmente en agricultura, se presenta como una posible solución para abordar este problema. No obstante, la reutilización se debe promover dentro de unos límites mínimos de calidad del agua, los cuales pueden alcanzarse mediante la implementación de eficientes tratamientos terciaros en las actuales plantas de tratamiento de aguas residuales urbanas. En las últimas décadas, los Procesos de Oxidación Avanzada (POA), basados en la generación de especies reactivas del oxígeno altamente oxidantes y no selectivas, se han planteado como alternativa a los tratamientos convencionales para desinfección y descontaminación de agua residual. El objetivo general de este estudio es, por tanto, la evaluación de nuevos POA para desinfección y descontaminación simultánea de agua, investigando: (i) fotocatálisis heterogénea solar con ZnO modificado (Ce, Yb y Fe) y TiO2-P25 de referencia, (ii) peroximonosulfato (PMS) bajo radiación solar natural (PMS/Solar), (iii) POA basados en radical sulfato utilizando PMS y radiación UV-C (PMS/UV-C) y (iv) combinación de ZnO modificado con PMS como estrategia de tratamiento. Los objetivos biológicos y químicos analizados en este estudio fueron: tres patógenos de impacto en salud humana (dos bacterias gram-negativas Escherichia coli, Pseudomonas spp y una gram-positiva Enterococcus spp) y tres Contaminantes de Preocupación Emergente (CE) (Diclofenaco-DCF, Sulfametoxazol-SMX y Trimetoprim-TMP). La fotoactividad de ZnO modificado con Ce, Yb o Fe se evaluó a escala de laboratorio (200 mL), obteniendo buenas cinéticas de inactivación bacteriana y degradación de CE. El ZnO-Ce mostró el mejor rendimiento, no obstante, se descartó el escalado de este proceso tanto su aplicación directa, considerando su similar eficiencia en comparación con TiO2-P25 y por el alto coste del tratamiento, como en combinación con PMS, por la la liberación de Zn2+ al agua tratada. El uso directo de PMS como agente oxidante para el tratamiento de agua y UWW se ha demostrado en este estudio, aumentado su eficiencia al ser el sistema irradiado tanto con lámparas UV-C como con luz solar natural. Se han postulado diferentes mecanismos de inactivación y degradación de CE para cada tipo de irradiación: activación de PMS para generar radicales (con fotones UV-C) y la no activación o mecanismo de oxidación directo (con luz solar natural). La capacidad de los procesos PMS/Solar y PMS/UV-C se evaluó en UWW a escala de planta piloto en un Colector Parabólico Compuesto (10 L) y en una planta piloto de UV-C (80 L), respectivamente. El mejor rendimiento de tratamiento se alcanzó con una concentración de PMS de 1 mM en ambos casos, logrando una inactivación exitosa de todos los objetivos microbianos (incluyendo bacterias resistentes a antibióticos), sin observar recrecimiento bacteriano tras 48 h y eliminando de manera eficiente los CE. Por otro lado, la eliminación eficiente de genes de resistentes a antibióticos y productos de transformación se obtuvo con PMS/UV-C, mientras que éstos parámetros siguen siendo un reto a abordar en el caso del proceso PMS/Solar. En ningún caso se observó toxicidad del agua tratada para Aliivibrio fischeri, excluyendo un efecto nocivo para el medio ambiente receptor del efluente, y solo un leve efecto fitotóxico en el crecimiento de dos de las tres semillas analizadas (L. sativum y S. alba), indicando la idoneidad del efluente para su reutilización en riego. Finalmente, el análisis de costes demostró que este factor clave podría ser una barrera importante para la implementación del proceso PMS/Solar en plantas centralizadas de tratamiento de UWW. No obstante, su consideración como sistemas descentralizados asociados a pequeños volúmenes de agua en zonas con alta incidencia de radiación solar, ahorrando costes energéticos mediante el aprovechamiento de la luz solar, podría ser una opción real y asequible. / [CA] El món s'enfronta a una profunda crisi associada a l'aigua i la reutilització d'aigües residuals urbanes (UWW), especialment en agricultura, es presenta com una possible solució per a abordar aquest problema. No obstant això, la reutilització s'ha de promoure dins d'uns límits mínims de qualitat de l'aigua, els quals poden aconseguir-se mitjançant la implementació d'eficients tractaments terciaris en les actuals plantes de tractament d'aigües residuals urbanes. En les últimes dècades, els Processos Avançats d'Oxidació (PAO), basats en la generació d'espècies reactives d'oxigen altament oxidants i no selectives, s'han plantejat com a alternativa als tractaments convencionals per a desinfecció i descontaminació d'aigua residual. L'objectiu general d'aquest estudi és, per tant, l'avaluació de nous POA per a desinfecció i descontaminació simultània d'aigua, investigant: (i) fotocatàlisi heterogènia solar amb ZnO modificat (Ce, Yb i Fe) i TiO2-P25 de referència, (ii) peroximonosulfat (PMS) baix radiació solar natural (PMS/Solar), (iii) POA basats en radical sulfat utilitzant PMS i radiació UV-C (PMS/UV-C) i (iv) combinació de ZnO modificat amb PMS com a estratègia de tractament. Els objectius biològics i químics analitzats en aquest estudi van ser: tres patògens d'impacte en salut humana (dos bacteris gram-negatius Escherichia coli, Pseudomonas spp i un gram-positiu Enterococcus spp) i tres Contaminants de Preocupació Emergent (CE) (Diclofenac-DCF, Sulfametoxazol-SMX i Trimetoprim-TMP). La fotoactivitat de ZnO modificat amb Ce, Yb o Fe es va avaluar a escala de laboratori (200 mL), obtenint bones cinètiques d'inactivació bacteriana i degradació de CE. El ZnO-Ce va mostrar el millor rendiment, no obstant això, es va descartar l'escalat d'aquest procés tant mitançant la seua aplicació directa o com en combinació amb PMS, considerant la seua similar eficiència en comparació amb TiO2-P25, l'alt cost del tractament i l'alliberament de Zn2+ a l'aigua tractada. L'ús directe de PMS com a agent oxidant per al tractament d'aigua i UWW s'ha demostrat en aquest estudi, augmentat la seua eficiència quan el sistema és irradiat tant amb llums UV-C com amb llum solar natural. S'han postulat diferents mecanismes d'inactivació i degradació de CE per a cada tipus d'irradiació: activació de PMS per a generar radicals (amb fotons UV-C) i la no activació o mecanisme d'oxidació directe (amb llum solar natural). La capacitat dels processos PMS/Solar i PMS/UV-C es va avaluar en UWW a escala de planta pilot en un Col·lector Parabòlic Compost (10 L) i en una planta pilot d'UV-C (80 L), respectivament. El millor rendiment de tractament es va aconseguir amb una concentració de PMS d'1 mm en tots dos casos, aconseguint una inactivació reeixida de tots els objectius microbians (incloent bacteris resistents a antibiòtics), sense observar recreixement bacterià després de 48 h i eliminant de manera eficient els CE. D'altra banda, l'eliminació eficient de gens de resistents a antibiòtics i productes de transformació es va obtindre amb PMS/UV-C, mentre que aquests paràmetres continuen sent un repte a abordar en el cas del procés PMS/Solar. En cap cas es va observar toxicitat a l'aigua tractada per a Aliivibrio fischeri, excloent un efecte nociu per al medi ambient receptor de l'efluent, i només un lleu efecte fitotòxic en el creixement de dos de les tres llavors analitzades (L. sativum i S. alba), indicant la idoneïtat de l'efluent per a la seua reutilització en reg. Finalment, l'anàlisi de costos va demostrar que aquest factor clau podria ser una barrera important per a la implementació del procés PMS/Solar en plantes centralitzades de tractament de UWW. No obstant això, la seua consideració com a sistemes descentralitzats associats a xicotets volums d'aigua en zones amb alta incidència de radiació solar, estalviant costos energètics mitjançant l'aprofitament de la llum solar, podria ser una opció real i assequible. / [EN] It is well recognized that the world is facing a water crisis and the reuse of urban wastewater (UWW) in agriculture, has been gaining attention as a reliable solution to address this problem. It is mandatory to promote the safe water reuse and minimum water quality limits could be achieved by upgrading the Urban Wastewater Treatment Plants, through the addition of an efficient tertiary treatment. In the last decades, Advanced Oxidation Processes (AOPs), relying on the potential generation of highly oxidant, reactive and non-selective Reactive Oxygen Species (ROS), have been raised as alternative to conventional treatments for both water disinfection and decontamination. The general aim of this study is the assessment of novel AOPs for the simultaneous disinfection and decontamination of water, investigating (i) solar heterogeneous photocatalysis, involving modified ZnO with Ce, Yb and Fe and the benchmark TiO2-P25, (ii) peroxymonosulfate (PMS) under natural solar radiation (PMS/Solar), (iii) Sulfate radical-based AOPs (SR-AOPs) involving PMS and UV-C radiation (PMS/UV-C) and (iv) combination of the best-performing photocatalytic material with PMS (PMS/modified ZnO). The involved biological and chemical targets in this study were: three human health impact pathogens (two gram-negative bacteria Escherichia coli, Pseudomonas spp. and the gram-positive Enterococcus spp.) and three Contaminants of Emerging Concern (CECs, Diclofenac-DCF, Sulfamethoxazole-SMX and Trimethoprim-TMP). Photoactivity of modified ZnO with Ce, Yb or Fe was assessed in 200-mL vessel reactors, attaining good target's removal kinetic rates. Best performing material was ZnO-Ce, but its feasibility for a further up-scaling was discarded both as photocatalyst alone, considering the similar performances obtained, compared to TiO2-P25 and the high treatment cost, and in combination with PMS, due to the release of high amount of Zn2+. PMS alone has been proven to be an effective oxidant agent for water and UWW treatment, increasing its effectiveness when illuminated with photons from UV-C lamps and natural sunlight. Nevertheless, different inactivation and CECs degradation mechanisms have been postulated for each type of irradiation, and according to the activation of PMS (with UV-C photons) or non-activation (under natural sunlight). The capability of PMS/Solar and PMS/UV-C processes were evaluated in actual UWW at pilot plant scale in 10-L Compound Parabolic Collector and in 80L UV-C pilot plant, respectively. Optimal load of PMS was found to be 1 mM in both cases, achieving successful inactivation of natural occurring bacteria and their antibiotic resistant counterparts, without observing bacterial regrowth after 48h and efficiently eliminating CECs. Efficient removal of antibiotic resistant genes (ARGs) and transformation products (TPs) was obtained by PMS/UV-C, while their elimination is still a challenge to be addressed in PMS/Solar process. Reclaimed UWW obtained by both PMS/Solar and PMS/UV-C process showed no toxicity towards Aliivibrio fischeri, excluding a harmful effect towards the receiving aquatic environment after effluent discharge, and a very slightly phytotoxic effect for growth of two out of the three tested seeds (L. sativum and S. alba), indicating the suitability of this water for its subsequent reuse for agriculture. The analysis of the treatment cost revealed that this key factor could be an important barrier for implementation of PMS/Solar process in large centralized UWW treatment plants. Nevertheless, its consideration as decentralized systems associated to small volume of water in areas with a high solar radiation incidence, saving energy costs by using natural solar radiation, could be a real and affordable option. / Berruti, I. (2022). Assessment of novel Advanced Oxidation Processes for the Simultaneous Disinfection and Decontamination of Water [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183052 / TESIS

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