Thesis (M.Sc.Res.)--University of Wollongong, 2008. / Typescript. Includes bibliographical references: leaf 90-83.

Thesis (M.Eng.Sc.) - University of Queensland, 2004. / Includes bibliography.

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Thesis (MSc )--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Washing and cleansing in an aqueous washing solution is a complex process involving the interaction of numerous physical and chemical processes. Investigations indicate that various factors present during repeated laundering might have an adverse effect on textile fabrics. Little is known, however, about the effect of the different mechanical wash actions on the deterioration of textiles. The automatic washing machines commonly used in South African households are often broadly classified as top loaders and front loaders. On closer inspection, however, it becomes clear that marked differences exist between the horizontal drum machines (H), vertical drum agitator type (V(A)) and vertical drum impeller type machines (V(/)). The effect of laundering on the wear life of textile fabrics has been extensively investigated, but a serious need for research on the effect of the different mechanical washing actions of the different washing machines on textile fabrics exists on both national and international level. A number of factors have an effect on textile deterioration during washing, e.g. number of washes, temperature of wash liquid, detergent type as well as fabric finishes and water quality. Fabric properties like changes in tensile strength, print deterioration and fraying, as well as electron microscope photographs, were used as indicators of mechanical deterioration to textiles. The broad aim of this exploratory study was firstly, to compare the effect of repeated washing in different domestic automatic washing machines (commonly used in South Africa) on the possible mechanical damage to textile fabrics and, secondly, to compare the soil removal efficiency of the mechanical wash actions of the different machines. An experimental study was therefore decided on. The washing of the test fabrics, as well as the testing, was carried out under controlled conditions in a laboratory. Apart from the different mechanical wash actions of the individual machines, the effect of the variables wash temperature, level of detergent and number of washes, was also investigated. This was done by measuring tensile strength, print deterioration and fraying propensity on samples laundered repeatedly at 40°C or 60°C, with and without detergent in the washing liquid, and comparing the colour change measured on laboratory-soiled test fabrics after washing. Analysis of the mechanical wash actions of the seven washing machines compared in this study indicated conspicuous differences among machines. It can be concluded that the mechanical wash action in the category V(A) machines is the most severe, and causes the highest reduction in tensile strength, the greatest print deterioration and the highest degree of fraying. These machines did not, however, exhibit greater soil removal efficiency than the other two categories of washing machines. The machines from category H did not exhibit a significantly different soil removal efficiency than those from category V(A), but their mechanical wash action proved to be less severe. Category V(/) machines seem to have the most delicate wash action and will probably cause the slightest fabric deterioration over the long term, but unfortunately produces poor soil removal efficiency results. This study also confirmed that washing fabrics in water alone causes more deterioration of tensile strength in fabrics than washing with detergent in the wash solution. Due to the limited scope and exploratory nature of this research/study, certain aspects of automatic washing machine processes could not be tested empirically. Recommendations for future research and implications for consumers were formulated. / AFRIKAANSE OPSOMMING: Was en skoonmaak in 'n waterige oplossing is 'n komplekse proses wat 'n interaksie tussen verskeie fisiese en chemiese prosesse behels. Ondersoeke dui aan dat verskeie van die faktore teenwoordig tydens herhaalde wasprosesse 'n nadelige effek op tekstielstowwe mag he. Baie min is egter bekend oor die effek van die verskillende meganiese wasaksies op die degenerasie van tekstiele. Die outomatiese wasmasjiene wat algemeen in Suid-Afrikaanse huishoudings gebruik word, word dikwels breedweg geklassifiseer as bolaaiers en voorlaaiers. By nadere ondersoek word dit egter duidelik dat daar opvallende verskille bestaan tussen die horisontale drom masjiene (H), die vertikale drom roerder tipe ((V)A)) en die vertikale drom stuwer tipe (V(/)) masjiene. Die effek van was op die draleeftyd van tekstielstowwe is uitvoerig ondersoek, maar daar bestaan op beide nasionale en internasionale vlak In ernstige behoefte aan navorsing oor die effek van die verskillende meganiese wasaksies van die verskillende wasmasjiene op tekstielstowwe. Faktore 5005 die aantal wasse, temperatuur van die wasoplossing, detergent tipe, water kwaliteit en tekstielstoftipe en -afwerking(s) het In effek of tekstieldegenerasie gedurende was. Tekstielstofeienskappe 5005 veranderinge in die breeksterkte van die tekstielstof of die tekstielstofmassa per eenheidsarea, agteruitgang van bedrukking, rafeling, sowel as elektronmikroskoop foto's word as aanduiding van meganiese degenerasie t.o.v. tekstiele beskou. Die oorkoepelende doe I van hierdie eksploratiewe studie was eerstens, om die effek te vergelyk van herhaalde was in verskillende outomatiese wasmasjiene (algemeen in gebruik in Suid-Afrika) op die moontlike meganiese beskadiging aan tekstielstowwe, en tweedens, om die doeltreffendheid van vuilverwydering op die wasaksies van die verskillende masjiene te vergelyk. Daar is gevolglik op In eksperimentele studie besluit. Die was van die tekstielstowwe, sowel as die laboratoriumtoetse, is onder gekontroleerde atmosferiese toestande in In laboratorium uitgevoer. Afgesien van die verskillende meganiese wasaksies van die individuele masjiene, is die effek van die veranderlikes westemperetuur, detergentv!ak en aanta! wasse ook ondersoek. Dit is gedoen deur die bepaling van breeksterkte en die meting van die mate van agteruitgang van bedrukking en mate van geneigdheid tot rafeling van kledingstowwe na herhaalde was by 40°C en 60°C, met en sonder detergent in die wasvloeistof. Die kleurverandering na was is ook gemeet op laboratorium gevlekte monsters. Die analise van die meganiese wasaksie van die sewe wasmasjiene wat in hierdie studie vergelyk is, het opvallende verskille tussen masjiene uitgewys. Daar kan tot die gevolgtrekking gekom word dat die meganiese wasaksie in kategorie V(A) masjiene die ergste is, wat gevolglik die grootste verlaging in breeksterkte en die meeste afieruitgang van bedrukking en rafeling veroorsaak het. Hierdie masjiene het egter nie meer doeltreffende vuilverwydering tot gevolg gehad in vergelyking met die ander kategoriee van wasmasjiene nie. Die masjiene in kategorie H het nie 'n betekenisvolle verskil in doeltreffenheid van vuilverwydering van die van kategorie V(A) getoon nie, maar die meganiese wasaksie was minder straf. Kategorie V(/) masjiene het blykbaar die mees delikate wasaksie en sal moontlik die minste tekstielstof degenerasie oor die langtermyn toon, maar ongelukkig is die resultate t.o. v. die doeltreffendheid van vuilverwydering swak. Die studie bevestig dat die was van tekstielstowwe in water aileen 'n groter verlaging in breeksterkte van tekstielstowwe veroorsaak as wat die geval is wanneer met 'n detergent in die wasvloeistof gewas word. Weens die beperkte omvang en eksploratiewe aard van die studie kon sekere aspekte van die outomatiese wasprosesse nie empiries getoets word nie. Aanbevelings vir toekomstige navorsing en implikasies vir verbruikers is geformuleer.

As fachadas das edificações, ao longo de sua vida útil, sofrem degradação devido a ataques de agentes químicos e à deposição de partículas na sua superfície. Como consequências, há perdas no desempenho de seus materiais e a desfiguração estética das fachadas por meio de manchas, implicando em ações de reparo que envolvem custos elevados. Os produtos atualmente disponíveis no mercado brasileiro com objetivo de evitar o manchamento de fachadas têm baixa eficiência, sendo que os principais deles adotam a técnica do pós-tratamento com hidrofugantes, os quais geralmente alteram a coloração do substrato e podem ser a origem de novas patologias. Usufruindo de novas tecnologias, o dióxido de titânio (TiO2) apresenta-se como material nanométrico amplamente estudado na área científica, sendo potencialmente utilizado como fotocalisador. O presente trabalho verificou a possibilidade de obtenção de superfícies autolimpantes a partir da adição de TiO2 em revestimentos de argamassa branca. Estas, a partir de propriedades fotocatalíticas do TiO2 podem ser tornar autolimpantes sob ação da radiação solar (UV) e da chuva. Foram confeccionadas argamassas de traço 1:2 e 1:3, com adições de 0%, 5% e 10% de TiO2 em relação à massa de cimento, com consistência fixa. As amostras foram aspergidas com diferentes agentes manchantes: azul de metileno, particulado de poluição, produto de corrosão, pichação; e sem manchamento (referência). Após, estas amostras foram expostas nas condições ambientais da cidade de Porto Alegre. Ao longo de 84 dias, foram realizadas leituras com espectrofotômetro portátil para avaliar o efeito autolimpante. Também foram verificadas as propriedades físico-mecânicas das argamassas. Os resultados apontaram que argamassas com adição de TiO2 necessitaram maior quantidade de água, apresentaram maior densidade no estado fresco e menor teor de ar incorporado. Ainda, a resistência à compressão foi elevada para o traço mais rico (1:2) e mantida constante para o traço pobre (1:3). Além disso, se mostraram mais claras/brancas quanto maior a porcentagem de adição. O efeito autolimpante pode ser percebido mais facilmente na mancha de azul de metileno, porém, a limpeza ocorreu tanto em argamassas com adição de TiO2, quanto em argamassas sem a adição. Em manchas que geraram uma película sobre a placa, o efeito autolimpante foi dificultado. / The facades of buildings, during their lifespan, suffer degradation due to attacks of chemical agents and due to deposition of particles on their surface. As consequences, there are losses on the performance of their materials and aesthetics disfiguration of the facades by stains, implying repairing actions involving high costs. The products available nowadays on the brasilian market with the purpose to avoid the staining of the facades have low efficiency, and the main products between them adopt the technique of post-treatment with hydrophobing, which generally modify the colour of the substrate and which can originate new pathologies. Taking advantage of new technologies, the titanium dioxide (TiO2) appears as a nanometric material widely studied in the scientific area, being pottentialy used as photocatalyser. The present work has verified the possibility of obtention of self-cleaning surfaces after addition of TiO2 in white mortar coverings. Those, from photocatalyser properties of the TiO2 can become self-cleaning under the action of solar radiation (UV) and rain. There were prepared mortars of trace 1:2 and 1:3, with additions of 0%, 5% and 10% of TiO2 in relation of the cement weight, with steady consistency. The samples were sprinkled with different staining agents: methylene blue, pollution particulates, corrosion product, graffiti; and without stains (reference). After that, these samples were exposed to the ambiental conditions of the city of Porto Alegre. Through 84 days, scannings were made with portable spectrophotometer to evaluate the self-cleaning effect. The physicalmechanical properties of the mortars were also verified. The results point out that mortars with addition of TiO2 required a bigger amount of water, they presented bigger density in the fresh state and smaller contents of incorporated air. Besides, the compression resistance was high to the richest trace (1:2) and remained constant to the poor trace (1:3). Moreover, they have showed themselves more clear/white as bigger was the percentage of addition. The self-cleaning effect can be more easily noticed on the methylene blue stain, however, the cleaning occurred both in mortars with addition of TiO2 and in mortars without the addition. In stains which generate a film above the plate, the self-cleaning effect was hampered.

Scania has identified a problem among certain costumers in very dusty environments. The air filters for their truck’s climate system need extensive maintenance, replacement or manual cleaning, because of dust frequently loading up the filters. In this thesis the problem has been analyzed in order to find a solution. The process was initiated by the usage of the black box method, where needed transformations were found, resulting in three needed technical systems. Thereafter, brainstorming was used to find concepts for each technical system. Concepts were compared and ranked against each other. For the most critical of the three systems, the cleaning action, prototypes were built of the four highest ranked concepts. These prototypes were then used to compare the performance between the concepts. The selected filter cleaning device consists of a method to analyze filter blockage, alert the driver when cleaning is needed and a system to clean the filter for the Scania climate system. The system consists of a pressure sensor used to measuring filter blockage, an air pulse system which cleans the filter and a controller unit to control the cleaning cycle and to inform the driver. The air pulse system has two main parts, a pulse valve and an air tank. The pulse valve is used for releasing the air accumulated in the air tank. The complete system is supplied with 8.5 bar from the internal air pressure system in the truck and a 24 V power supply, also located in the truck. A suggestion on how a final implementation can be done has been developed, with a minimized number of variants and modifications of parts already in production. A proof of concept was built and mounted in a truck to validate the complete system. Numbers on cleaning performance and sound levels have been produced. The proof of concept manages to remove the restriction created from dust by approximately 50 %. Aside from developing a suitable filter cleaning device, figures on when the filter needs to be cleaned have been identified. To keep a good working environment within the cab a pressure drop over the filter of 936 Pa is recommended as a point of cleaning. This is to maintain the needed airflow of at least 123 m3/h with two persons seated in the cab to not exceed regulated levels of CO2 within the truck cab.

Diploma thesis focuses on the topic of cleaning boilers in heating and power generation industry and automation of boiler cleaning process. There are summarized facts about cleaning devices, from which these systems consist of and as well as about support and control devices. Based on this facts, is developed control system and visualization interfaces with an emphasis on functionality into the system.

Panos de limpeza têm sido considerados importantes fontes de contaminação cruzada, contudo seu uso continua muito freqüente em serviços de alimentação. O objetivo desse trabalho foi avaliar a contaminação e multiplicação microbiana, além de dois procedimentos de higienização de panos de limpeza. Em uma primeira etapa, 35 panos de limpeza foram coletados em serviços de alimentação da grande Porto Alegre, RS/Brasil e foram submetidos à quantificação de bactérias totais, coliformes e Staphylococcus coagulase positiva, aqui chamado de Staphylococcus aureus presuntivos. Os panos foram lavados manualmente e desinfetados por dois métodos, separadamente: a) fervura em água potável por 15 minutos e b) imersão em solução clorada a 200ppm, por 15 minutos, sendo enxaguados logo após. Os resultados demonstraram que a as contagens de bactérias totais variaram de 2,0 x 104 UFC/cm2 até 1,0 x 108 UFC/cm2, com média de 9,1 x 106 UFC/cm2. A contaminação por coliformes foi de 4,4 x 102 a 1,6 x 107 UFC/cm2, sendo que 40% das amostras apresentou contagens de aproximadamente 106 UFC/cm2. Quantidades de S. aureus presuntivos variaram de 1,0 x 104 UFC/cm2 a 2,8 x 106 UFC/cm2, com média de 4,6 x 105 UFC/cm2. De modo geral, panos desinfetados pelos dois métodos demonstraram reduções significativas (p < 0,05) do número de microrganismos, as quais foram de aproximadamente 5 ciclos logarítmicos. Em uma segunda etapa, panos contendo diferentes quantidades de matéria orgânica (0%, 1%, 5% e 10% de albumina bovina) foram contaminados com Salmonella Enteritidis 3091/05, Escherichia coli ATCC 25972, Staphylococcus aureus ATCC 25923 e Shigella sonnei CC07 e incubados por 1h, 2h, 3h e 4h, a 30 oC. A multiplicação foi avaliada por métodos microbiológicos e por bioluminescência gerada por ATP. Uma bactéria recombinante, ampicilina-resistente (HSα E. coli) foi utilizada para avaliar o potencial de dispersão de panos. Os resultados demonstraram que até duas horas de incubação não houve multiplicação expressiva de todos os microrganismos avaliados, no entanto, em três horas a maioria apresentou leve aumento da população. Uma exceção foi a S. Enteritidis que apresentou multiplicação significativamente maior (p < 0,05). Após quatro horas de incubação, todos os microrganismos apresentaram multiplicação significativa. A bioluminescência confirmou esses resultados e também demonstrou que diferentes quantidades de matéria orgânica não interferiram na multiplicação microbiana nas primeiras 3 a 4 horas. O experimento da dispersão bacteriana demonstrou que um pano contaminado com 104 UFC/cm2 foi capaz de transferir aproximadamente 102 UFC/cm2 de bactérias para uma superfície de aço inoxidável. Baseado nesses resultados, pode-se concluir que panos de limpeza utilizados em serviços de alimentação apresentavam nível elevado de contaminação, porém se adequadamente lavados e desinfetados, suas contagens podem ser significativamente reduzidas. Além disso, sugere-se que panos adequadamente desinfetados sejam utilizados por aproximadamente duas horas, não ultrapassando o período de três horas. / Cleaning cloths have been considered as important cause of cross-contamination, however its use remains frequent in food services. The objective of this study was to evaluate microbial contamination and multiplication, as well as two disinfection methods of cleaning cloths. In a first step of this work, samples (n=35) were collected in food services of Porto Alegre City, RS/Brazil and quantified for microbial contamination. Results indicated total aerobic counts varying from 2.0 x 104 cfu/cm2 up to 1.0 x 108 cfu/cm2, with mean numbers of 9.1 x 106 cfu/cm2. Coliform contamination varied from 4.4 x 102 up to 1.6 x 107 cfu/cm2 per cloth, and 40 % of the samples presented counts around 106 cfu/cm2, while presumptive S. aureus ranged from 1.0 x 104 cfu/cm2 up to 2.8 x 106 cfu/cm2, with mean numbers of 4.6 x 105 cfu/cm2. The cleaning cloths were disinfected in boiling water for 15 minutes and with 200 ppm sodium hypochlorite solution for 15 minutes, separately, demonstrating significant reductions (p < 0.05) of approximately 5 log. In a second step of this study, cloths containing 0 %, 1 %, 5%, and 10% of organic matter (bovine albumin) were contaminated with Salmonella Enteritidis 3091/05, Escherichia coli ATCC 25972, Staphylococcus aureus ATCC 25923 and Shigella sonnei CC07, and were incubated for 1 h, 2 h, 3 h, and 4 h, at 30 oC. Microbial multiplication was evaluated by bacterial counts and ATP bioluminescence, and an ampicilin-resistant recombinant HSα E. coli was used as a pathogen surrogate to investigate the potential of microbial cloth dispersion. The results demonstrate that until 2 hours of storage all strains did not present expressive growth. In 3 hours of storage the majority of the microorganisms showed slightly development, being that S. Enteritidis grown significantly better than other strains. In 4 hours of incubation all microorganisms demonstrate significant growth (p < 0.05). ATP bioluminescence confirmed the microbial count results and also demonstrates that different amounts of organic matter did not interfere with the bacterial multiplication at the first 3 to 4 hours of incubation. The dispersion experiment indicated that a cleaning cloth contaminated with 104 cfu/cm2 was able to spread approximately 102 cfu/cm2 recombinant E. coli onto a stainless steel surface. Based on these results it was possible to conclude that cleaning cloths used in food services were very contaminated, however adequate sanitation procedures could reduce significantly its microbial contamination. We suggested that an appropriate period of time to use disinfected cleaning cloths is around 2 hours, not exceeding 3 hours of usage.

Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2013-05-14T13:47:26Z No. of bitstreams: 1 Tese Eliane Sales. 2009.pdf: 1048115 bytes, checksum: 8d0649e6a5b1c164e8e4e6745ed1a3e7 (MD5) / Approved for entry into archive by Maria Creuza Silva(mariakreuza@yahoo.com.br) on 2013-05-14T13:47:48Z (GMT) No. of bitstreams: 1 Tese Eliane Sales. 2009.pdf: 1048115 bytes, checksum: 8d0649e6a5b1c164e8e4e6745ed1a3e7 (MD5) / Made available in DSpace on 2013-05-14T13:47:48Z (GMT). No. of bitstreams: 1 Tese Eliane Sales. 2009.pdf: 1048115 bytes, checksum: 8d0649e6a5b1c164e8e4e6745ed1a3e7 (MD5) Previous issue date: 2009 / Esta tese apresenta o resultado da investigação sobre assédio moral no trabalho e Transtornos Mentais Comuns TMC entre trabalhadores de uma empresa do setor de serviços, especializada em serviços de limpeza. Nesta pesquisa foram desenvolvidos três estudos em forma de artigos. O primeiro de corte transversal, de caráter exploratório, para análise da prevalência de assédio moral no trabalho na população estudada. Foram identificadas também, condições de maior vulnerabilidade social entre os sujeitos expostos ao assédio moral. A definição de caso foi feita a partir do uso do Questionário de Atos Negativos QuAN, uma versão brasileira do Negative Acts Questionnaire NAQ, a partir da referência de exposição semanal ou diária. O segundo artigo, correspondeu a um estudo exploratório realizado a partir da aplicação do QuAN, com vistas a analisar os atos negativos mais frequentemente relatados e as médias de respostas positivas aos atos, conforme o status sócio-demográfico e ocupacional dos trabalhadores. Apresentou-se ainda, o perfil dos sujeitos considerados perpetradores. O terceiro estudo, com desenho tipo corte transversal, de caráter confirmatório objetivou verificar a associação entre assédio moral no trabalho e Transtorno Mentais Comuns. Para estabelecer a variável dependente utilizou-se o Self Report Questionnaire-20 SRQ-20. Os resultados das análises procedidas nos três artigos, apontam para uma prevalência elevada de assédio entre os trabalhadores, compatível com achados de pesquisas de base populacional. Os atos negativos direcionados ao campo profissional foram referidos mais frequentemente. Observou-se por fim, uma forte associação entre assédio moral no trabalho e transtornos mentais comuns, mesmo quando ajustada por fatores sócio-demográficos e ocupacionais. Evidenciou-se que o tempo na empresa pode implicar em maiores chances dos indivíduos assediados apresentarem TMC. A discussão sobre a ocorrência e o impacto do assédio moral no trabalho na saúde mental dos trabalhadores deve ser fomentada com vista à busca de soluções para um problema que já se delineia como questão de saúde pública no Brasil. / Salvador