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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.
41

Análise cromatografica de biocidas anti-incrustantes em amostras de água de mar e tecido de moluscos / Chromatographic analysis of booster antifouling biocides in seawater samples and molluscs tissue

Lia Gracy Rocha Diniz 02 September 2016 (has links)
A indústria naval é uma das mais importantes para economia e desenvolvimento de um país, no entanto, as diversas atividades desenvolvidas em zonas portuárias contribuem para o impacto ambiental a ambientes costeiros, dentre os vários grupos de micropoluentes orgânicos potencialmente danosos a esses ecossistemas, emergiram nos últimos anos os biocidas anti-incrustantes. Pinturas anti-incrustantes são tratamentos utilizados para minimizar processos corrosivos, diminuindo custos com manutenção, economizando combustíveis e reduzindo a veiculação de espécies não nativas entre ecossistemas costeiros. Neste estudo foi desenvolvido, validado e aplicado um método analítico para determinação dos biocidas anti-incrustantes, clorotalonil, diuron, irgarol e tiram em amostras de água, e tecido biológico em diferentes regiões portuárias da costa brasileira e da Ilha de Gran Canaria -Espanha. / The maritime industry is an important aspect of a countries economy, however, the cumulative activities of port areas has an impact on coastal environments, this can include the addition of harmful micro-organic material. Among the potentially harmful micro-organic material being added to ecosystems, are recently emerged anti-fouling biocidal paints. Anti-fouling paints are used as a treatment to minimize corrosive processes, reduce maintenance costs, save fuel and reduce the transmission of non-native species to coastal ecosystems. This study developed, validated and applied an analytical method for the determination of the anti-fouling biocidal paints, chlorothalonil, diuron, irgarol and tiram in water samples and biological tissue in different port areas of the Brazilian coast and the Gran Canaria Island in Spain.
42

Ecotoxicological effects from three antifouling paints on the red macroalga <em>Ceramium tenuicorne.</em>

Krantz-Frid, Madelene January 2009 (has links)
<p>Antifouling paints are applied on vessels to prevent growth of fouling organisms such hasbarnacles. Presently, there are a number of different paints available on the Swedish marketwith different strategies and active substances. The paints might work by either continuouslyreleasing biocides or physically by peeling off or provide an easily cleansed surface whereorganisms cannot attach. The physically working paints do not need to register an activesubstance since its purpose is not to affect living organisms by a chemical or biological modeof action. In this study, two commercially available paints, the copper-based Fabi 3959(International Paint Ltd) and physically eroding, biocide-free labelled Mille Light (HempelFärg AB) were compared to Hard Racing superior, containing copper and the forbiddensubstance Tributyltin. Fabi International is only allowed to be used on the Swedish west coastdue to 6% added as active substance while the biocide-free Mille Light is eligible for eastcoast usage. The toxic effect from respective paint was investigated by assembling a growthinhibition test with the red macro alga Ceramium tenuicorne. The results show that all thestudied paints had a negative effect on growth and therefore leaked substances inconcentrations high enough to be harmful to the alga. The toxic response differed with theeffect on growth being in the following order, Hard racing superior>Fabi >Mille Light.Implications regarding the current legalization involving biocide-free labelled antifoulingpaints are discussed.</p>
43

Incidence des pratiques d'entretien des toitures sur la qualité des eaux de ruissellement : cas des traitements par produits biocides

Van De Voorde, Antoine, Van De Voorde, Antoine 06 June 2012 (has links) (PDF)
Ce travail de thèse a dans un premier temps permis de mettre en évidence les différentes pratiques de traitement de toiture existantes en France. Après avoir sélectionné la pratique de traitement majoritaire (à savoir le traitement biocide), le protocole d'analyse de la molécule la plus répandue dans les différents produits : le benzalkonium (ou alkyldiméthylbenzylammonium) a été développé. Ce protocole a ensuite été appliqué pour évaluer les niveaux de concentration en biocide dans l'eau de ruissellement de toiture après un traitement. Une double approche a été mise en œuvre : "Suivi sur une durée d'un an des flux de benzalkonium dans les eaux de ruissellement de 12 bancs d'essais exposés en conditions naturelles", évaluation en condition de pluie simulée au laboratoire de différents paramètres (nature du matériau de couverture, dosage du produit et intensité de la pluie) sur les processus d'émission du benzalkonium. Enfin, l'ensemble des données acquises ont permis d'évaluer l'incidence sur la contamination des eaux de ruissellement de toiture après un traitement biocide, à une échelle locale et à l'échelle d'un petit bassin versant résidentiel. Le suivi de la contamination des eaux de ruissellement par bancs d'essais a permis de mettre en évidence une très forte contamination en benzalkonium dans les premiers millimètres de pluie (5 à 27 mg/L), très supérieures aux EC50 disponibles pour les organismes aquatiques (5,9 µg/L) et dépendante de la nature du matériau de toiture utilisé, les tuiles en terre cuite ayant émis moins de biocide que les tuiles en béton. La contamination diminue avec la succession des pluies, mais reste significative plusieurs mois après le traitement. Par ailleurs, l'étude au laboratoire a montré que l'état de surface des tuiles influence beaucoup le lessivage. Ainsi, les tuiles très imperméables en surface ont émis une quantité de benzalkonium proportionnelle à la masse épandue lors du traitement, alors que les tuiles sans traitement de surface ne sont pas sensibles au dosage du produit. A l'échelle locale, des précautions doivent être prise lors d'un traitement de toiture vis-à-vis de la collecte / utilisation des eaux de ruissellement. En effet, les très fortes concentrations en benzalkonium dans les premières pluies suivant le traitement peuvent avoir des impacts sur les végétaux arrosés, sur l'équilibre microbien de la cuve de récupération, voir des effets irritants sur l'homme. Une déconnexion minimale de 3 à 5 mois de la cuve permettrait de limiter les risques. Enfin, sur la base des résultats des bancs d'essais et d'un travail d'enquête sur l'étendue des pratiques de traitement, les concentrations et flux de benzalkonium susceptibles d'être émis dans les eaux pluviales d'un bassin versant résidentiel ont été modélisés. Les résultats mettent en évidence une contamination significative des eaux pluviales, liée essentiellement à la phase particulaire. La masse annuelle de benzalkonium exportée dans les eaux pluviales pourrait être de l'ordre de 0,85 kg / ha imperméabilisé / an
44

Produção in vitro de biofilme em canetas odontológicas e eficiência de diferentes tratamentos na sua remoção / In vitro production of biofilm in dental pens and efficiency of different treatments in removal²

Freitas, Valdionir da Rosa January 2010 (has links)
Em consultórios odontológicos são utilizadas canetas rotatórias que durante seu uso entram em contato com a microbiota oral, podendo trazer conseqüências para o próprio paciente ou para outros que utilizarem o mesmo equipamento, se não houver um tratamento apropriado para sua reutilização. Para avaliar a eficiência de diferentes tratamentos utilizados rotineiramente na limpeza e desinfecção de equipamentos odontológicos, este trabalho descreve a produção de biofime in vitro em superfície de canetas odontológicas e a eficiência dos biocidas glutaraldeído, ácido peracético e álcool 70%, do detergente enzimático e da lavagem ultra-sônica para remoção do biofilme induzido, utilizando amostras de Pseudomonas aeruginosa e Staphylococcus aureus. Para a padronização dos métodos, além de curvas de crescimento de ambos os micro-organismos, foram realizados testes de adesão em cupons obtidos pelo corte das canetas. Foram testados diferentes tempos de incubação para a produção do biofilme, cujo valor máximo foi obtido em 14 dias. A avaliação da formação de biofilme foi realizada pelo método de contagem de bactérias viáveis (CBV), por microscopia eletrônica de varredura (MEV) e pelo método Cristal Violeta. A eficiência dos tratamentos na remoção do biofilme foi determinada pela diferença entre o número de células aderidas aos cupons submetidos ao tratamento e os cupons não submetidos. Maior remoção foi observada nos cupons tratados com ácido peracético, glutaraldeído e álcool 70% comparados aqueles tratados com detergente enzimático, lavagem ultra-sônica e solução salina. Os três primeiros tiveram eficiências similares, demonstradas pelos métodos CBV e MEV. O efeito dos tratamentos em S.aureus foi semelhante ao observado em P. aeruginosa, exceto a lavagem ultra-sônica que em S.aureus demonstrou melhor desempenho. Os tratamentos utilizados neste trabalho reduziram o biofilme em cupons de canetas odontológicas, mas não o removeram completamente, comprometendo a biossegurança na reutilização das canetas. / Rotating pens during its use in dental offices come into contact with the oral microbiota and may bring consequences to the patient or to others who use the same equipment, if there is not a clean suitable for reuse. To evaluate the efficiency of different treatments utilized routinely for cleaning dental equipments, this study describes the in vitro biofilm production on surfaces of dental pens and the efficiency of the biocides glutaraldehyde, peracetic acid, alcohol 70%, detergent enzyme and ultrasound rinsing for biofilm removal, using Pseudomonas aeruginosa and Staphylococcus aureus strains. For the standardization of methods, and growth curves of both microorganisms, adhesion tests were performed on coupons obtained by cutting the pens. We tested different incubation times for the production of biofilm, whose maximum value was obtained in 14 days. Evaluation of biofilm formation was performed by the method of counting viable bacteria (CBV) and scanning electron microscopy (SEM) and Crystal Violet method.The efficiency of treatments on biofilm removal was determined by the difference between the number of cells attached to coupons submitted and not submitted to treatment. Higher removal was observed on the coupons treated with peracetic acid, glutaraldehyde and 70% alcohol than in those treated with enzyme detergent, ultrasonic washing and saline. The first three had similar efficiencies, as demonstrated by CBV and SEM. The effect of treatment on S. aureus was similar to that observed in P. aeruginosa, except for ultrasonic washing in S. aureus that showed better performance. Therefore, the treatments used in this work reduced but not completely removed the biofilm in dental coupons pens, which can compromise the biological safety when they are reused.
45

Produção in vitro de biofilme em canetas odontológicas e eficiência de diferentes tratamentos na sua remoção / In vitro production of biofilm in dental pens and efficiency of different treatments in removal²

Freitas, Valdionir da Rosa January 2010 (has links)
Em consultórios odontológicos são utilizadas canetas rotatórias que durante seu uso entram em contato com a microbiota oral, podendo trazer conseqüências para o próprio paciente ou para outros que utilizarem o mesmo equipamento, se não houver um tratamento apropriado para sua reutilização. Para avaliar a eficiência de diferentes tratamentos utilizados rotineiramente na limpeza e desinfecção de equipamentos odontológicos, este trabalho descreve a produção de biofime in vitro em superfície de canetas odontológicas e a eficiência dos biocidas glutaraldeído, ácido peracético e álcool 70%, do detergente enzimático e da lavagem ultra-sônica para remoção do biofilme induzido, utilizando amostras de Pseudomonas aeruginosa e Staphylococcus aureus. Para a padronização dos métodos, além de curvas de crescimento de ambos os micro-organismos, foram realizados testes de adesão em cupons obtidos pelo corte das canetas. Foram testados diferentes tempos de incubação para a produção do biofilme, cujo valor máximo foi obtido em 14 dias. A avaliação da formação de biofilme foi realizada pelo método de contagem de bactérias viáveis (CBV), por microscopia eletrônica de varredura (MEV) e pelo método Cristal Violeta. A eficiência dos tratamentos na remoção do biofilme foi determinada pela diferença entre o número de células aderidas aos cupons submetidos ao tratamento e os cupons não submetidos. Maior remoção foi observada nos cupons tratados com ácido peracético, glutaraldeído e álcool 70% comparados aqueles tratados com detergente enzimático, lavagem ultra-sônica e solução salina. Os três primeiros tiveram eficiências similares, demonstradas pelos métodos CBV e MEV. O efeito dos tratamentos em S.aureus foi semelhante ao observado em P. aeruginosa, exceto a lavagem ultra-sônica que em S.aureus demonstrou melhor desempenho. Os tratamentos utilizados neste trabalho reduziram o biofilme em cupons de canetas odontológicas, mas não o removeram completamente, comprometendo a biossegurança na reutilização das canetas. / Rotating pens during its use in dental offices come into contact with the oral microbiota and may bring consequences to the patient or to others who use the same equipment, if there is not a clean suitable for reuse. To evaluate the efficiency of different treatments utilized routinely for cleaning dental equipments, this study describes the in vitro biofilm production on surfaces of dental pens and the efficiency of the biocides glutaraldehyde, peracetic acid, alcohol 70%, detergent enzyme and ultrasound rinsing for biofilm removal, using Pseudomonas aeruginosa and Staphylococcus aureus strains. For the standardization of methods, and growth curves of both microorganisms, adhesion tests were performed on coupons obtained by cutting the pens. We tested different incubation times for the production of biofilm, whose maximum value was obtained in 14 days. Evaluation of biofilm formation was performed by the method of counting viable bacteria (CBV) and scanning electron microscopy (SEM) and Crystal Violet method.The efficiency of treatments on biofilm removal was determined by the difference between the number of cells attached to coupons submitted and not submitted to treatment. Higher removal was observed on the coupons treated with peracetic acid, glutaraldehyde and 70% alcohol than in those treated with enzyme detergent, ultrasonic washing and saline. The first three had similar efficiencies, as demonstrated by CBV and SEM. The effect of treatment on S. aureus was similar to that observed in P. aeruginosa, except for ultrasonic washing in S. aureus that showed better performance. Therefore, the treatments used in this work reduced but not completely removed the biofilm in dental coupons pens, which can compromise the biological safety when they are reused.
46

Použití Persterilu v praxi k prevenci mykóz jiker ryb a jeho účinnost v antiparazitálních koupelích kaprovitých ryb v porovnání s užívanými přípravky / Practical use of Persteril for the prevention of fungal infections of fish roe and its effectiveness in antiparasitic baths cyprinids compared with used liquids

FOŘT, Ondřej January 2011 (has links)
Persteril (Acidum peraceticum) is a trademark used for a disinfectant with peracetic acid as an active ingredient. It is highly effective biocide and has extensive application possibilities with regard to environmental friendliness, it also has the widest range of disinfection efficacy. The practical part took place in the Genetic centre hatchery at the FROV JU in Vodnany. Persteril? was used for Short-time bath followed by rearing roe in the recirculating system and for short-time bath followed by rearing roe in the flow system. Both versions are breeding quite well; Persteril? detects fungal infection of fish roe in comparison with other liquids, as well as it leaves smaller or no residue in the water or out of the water until the evaporation (according to the concentration).
47

Produção in vitro de biofilme em canetas odontológicas e eficiência de diferentes tratamentos na sua remoção / In vitro production of biofilm in dental pens and efficiency of different treatments in removal²

Freitas, Valdionir da Rosa January 2010 (has links)
Em consultórios odontológicos são utilizadas canetas rotatórias que durante seu uso entram em contato com a microbiota oral, podendo trazer conseqüências para o próprio paciente ou para outros que utilizarem o mesmo equipamento, se não houver um tratamento apropriado para sua reutilização. Para avaliar a eficiência de diferentes tratamentos utilizados rotineiramente na limpeza e desinfecção de equipamentos odontológicos, este trabalho descreve a produção de biofime in vitro em superfície de canetas odontológicas e a eficiência dos biocidas glutaraldeído, ácido peracético e álcool 70%, do detergente enzimático e da lavagem ultra-sônica para remoção do biofilme induzido, utilizando amostras de Pseudomonas aeruginosa e Staphylococcus aureus. Para a padronização dos métodos, além de curvas de crescimento de ambos os micro-organismos, foram realizados testes de adesão em cupons obtidos pelo corte das canetas. Foram testados diferentes tempos de incubação para a produção do biofilme, cujo valor máximo foi obtido em 14 dias. A avaliação da formação de biofilme foi realizada pelo método de contagem de bactérias viáveis (CBV), por microscopia eletrônica de varredura (MEV) e pelo método Cristal Violeta. A eficiência dos tratamentos na remoção do biofilme foi determinada pela diferença entre o número de células aderidas aos cupons submetidos ao tratamento e os cupons não submetidos. Maior remoção foi observada nos cupons tratados com ácido peracético, glutaraldeído e álcool 70% comparados aqueles tratados com detergente enzimático, lavagem ultra-sônica e solução salina. Os três primeiros tiveram eficiências similares, demonstradas pelos métodos CBV e MEV. O efeito dos tratamentos em S.aureus foi semelhante ao observado em P. aeruginosa, exceto a lavagem ultra-sônica que em S.aureus demonstrou melhor desempenho. Os tratamentos utilizados neste trabalho reduziram o biofilme em cupons de canetas odontológicas, mas não o removeram completamente, comprometendo a biossegurança na reutilização das canetas. / Rotating pens during its use in dental offices come into contact with the oral microbiota and may bring consequences to the patient or to others who use the same equipment, if there is not a clean suitable for reuse. To evaluate the efficiency of different treatments utilized routinely for cleaning dental equipments, this study describes the in vitro biofilm production on surfaces of dental pens and the efficiency of the biocides glutaraldehyde, peracetic acid, alcohol 70%, detergent enzyme and ultrasound rinsing for biofilm removal, using Pseudomonas aeruginosa and Staphylococcus aureus strains. For the standardization of methods, and growth curves of both microorganisms, adhesion tests were performed on coupons obtained by cutting the pens. We tested different incubation times for the production of biofilm, whose maximum value was obtained in 14 days. Evaluation of biofilm formation was performed by the method of counting viable bacteria (CBV) and scanning electron microscopy (SEM) and Crystal Violet method.The efficiency of treatments on biofilm removal was determined by the difference between the number of cells attached to coupons submitted and not submitted to treatment. Higher removal was observed on the coupons treated with peracetic acid, glutaraldehyde and 70% alcohol than in those treated with enzyme detergent, ultrasonic washing and saline. The first three had similar efficiencies, as demonstrated by CBV and SEM. The effect of treatment on S. aureus was similar to that observed in P. aeruginosa, except for ultrasonic washing in S. aureus that showed better performance. Therefore, the treatments used in this work reduced but not completely removed the biofilm in dental coupons pens, which can compromise the biological safety when they are reused.
48

The use of dioxy MP 14 (stabilized aqueous chlorine dioxide) to control environmental airborne microorganisms

Mbamalu, Oluchi Nneka January 2009 (has links)
Magister Pharmaceuticae - MPharm / Dioxy MP 14 is a locally developed form of stabilized chlorine dioxide in an aqueous medium. It has all the sanitizing properties of chlorine dioxide gas, a neutral compound of chlorine in the +IV oxidation state, which has been used extensively as a non-toxic sterilizing agent with various applications. In this study, Dioxy MP14 was tested in a commercial chicken pen to determine its effectiveness as an environmental sanitizing agent. Control of environmental microbes in a chicken pen is important to ensure healthy birds and optimum egg production. The biocide was introduced via an overhead misting system with a variable dosing pump at various daily frequencies.The effectiveness of environmental microorganism control was determined with air settle plates. The health and performance of the chickens were evaluated and compared to chickens in a control pen.The results show a decrease in airborne microbial load in the treated pen. Better egg production and lower mortality of the chickens in the treated pen compared to the control pen, indicate effective environmental microbial control was achieved with a residual 7.46 ppm Dioxy MP 14 at a daily dose given for 5 minutes every 2 hours.This study was a pilot study, with encouraging results, for an extended study to investigate the feasibility of introducing Dioxy MP 14 through a misting system in a clinical environment (clinics and hospitals) to control airborne pathogens like Mycobacterium tuberculosis thereby reducing the infection risks for clinical workers and medical staff.
49

Greffage de copolymères antibactériens sur des surfaces PVC par chimie Click / Antibacterial copolymers grafting onto PVC surfaces by click chemistry

Lafarge, Jérôme 20 December 2012 (has links)
Dans le cadre de ce travail, l’objectif était d’élaborer des surfaces PVC antibactériennes. Deux types de surfaces ont été élaborés, des surfaces bactéricides visant à tuer les bactéries au contact et des surfaces antiadhésives (bactériophobes) empêchant ou limitant l’adhésion bactérienne.Pour ce faire, des copolymères porteurs de groupements cationiques bactéricides ainsi que des copolymères renfermant des structures à effets antiadhésifs de type polysaccharides ou PEG ont été synthétisés et caractérisés. Ces composés ont été ensuite greffés chimiquement par click addition sur des surfaces PVC porteuses de fonctions azoture (PVC-N3). Les propriétés physico-chimiques des nouvelles surfaces obtenues ont été caractérisées par diverses techniques (IRTF, XPS, angle de contact, AFM, microscopie confocale à fluorescence, ATG etDSC). Les propriétés bactéricides ou antiadhésives ont été évaluées à l’égard de Escherichia coli et Staphylococcus epidermidis. La microscopie confocale à fluorescence a mis en évidence le caractère hautement bactéricide des surfaces PVC cationiques via le test Live and Dead.Cette technique a aussi permis de démontrer l’effet antiadhésif de la méthyl cellulose, del’hydroxyéthyl cellulose et du PEG greffés en surface, diminuant d’au moins 10⁴ fois le nombre de bactéries adhérées par rapport aux surfaces témoins. / This work aimed to elaborate antibacterial PVC surfaces. Two kinds of surface were prepared, i.e. non leaching bactericidal surfaces killing bacteria by contact and antiadhesive (bacteriarepellent) surfaces preventing or limiting bacteria attachment. Thus, copolymers bearing cationic bactericidal groups as well as copolymers bearing polysaccharide or PEG antiadhesive structures were synthesized and characterized. These polymers were then successfully grafted by click chemistry onto PVC surfaces bearing azide groups (PVC-N3).The physico-chemical properties of the obtained surfaces were assessed by several techniques(FTIR, XPS, contact angle measurements, AFM, confocal fluorescence microscopy, TGA and DSC). The bactericidal and antiadhesive properties were assessed against Escherichia coli and Staphylococcus epidermidis. The fluorescence microscopy evidenced the high bactericidal effect of the cationic surfaces, using the Live and Dead test. This microscopytechnique has also shown high bacteria repellent effect of the surfaces based on methyl cellulose, hydroxyethyl cellulose and PEG, i.e. decrease of bacteria attachment by more than 10⁴ fold compared to the ungrafted surface.
50

Identifications of Different Microbiologically Influenced Corrosion (MIC) Mechanisms and MIC Mitigation Using Enhanced Biocide Treatment

Wang, Di 24 May 2022 (has links)
No description available.

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