Procedimentos analíticos baseados em medidas de quimiluminescência caracterizam-se por apresentar alta sensibilidade, baixos limites de detecção, ampla faixa de resposta linear e instrumentação simples. Uma das principais dificuldades relacionadas a este tipo de medida é maximizar a quantidade de radiação detectada, já que a emissão ocorre em todas as direções, o que dificulta o posicionamento adequado da cela de medida em relação ao sistema de detecção. Uma alternativa consiste na utilização de guias de ondas, que são dispositivos que conduzem a radiação emitida, minimizando perdas durante o transporte, tal como ocorre nos cabos de fibras ópticas. O acoplamento de sistemas de análises em fluxo com detecção por quimiluminescência é bastante conveniente, já que a mistura entre amostras a reagentes precisa ser rápida e altamente reprodutível, além de ser realizada a uma distância muito pequena do sistema de detecção, devido ao curto tempo de vida dos intermediários no estado excitado. Neste trabalho, é apresentada a avaliação de uma cela constituída por um guia de ondas para medidas de quimiluminescência. Estas ferramentas foram aplicadas à determinação de hipoclorito em amostras de líquido de Dakin por quimiluminescência empregando a reação de oxidação do luminol por hipoclorito. Também foi desenvolvido um procedimento analítico para a determinação de salbutamol, explorando a inibição da quimiluminescência da reação de oxidação de luminol por hipoclorito, caracterizando-se como uma alternativa promissora para a quantificação do fármaco. Em ambas as aplicações, os resultados foram concordantes com os obtidos por procedimentos de referência a nível de confiança de 95% / Analytical procedures based on chemiluminescence are characterized by high sensitivity, low detection limits, wide linear response ranges and simple instrumentation. One of the main troubles is to increase the amount of detected radiation, because emission occurs in all directions, making difficulty the positioning of the measurement cell in relation to the detection system. An alternative consists in the use of liquid-core waveguides, devices that constrain the emitted radiation, minimizing losses during the transport, in a similar way to optical fibers. Coupling flow analysis to chemiluminescence is attractive, because sample and reagents mixing needs to be fast, highly reproducible and accomplished close to the detector, in view of the short lifetime of the intermediates in the excited state. In this work, a cell constituted by a liquid-core waveguide was evaluated for chemiluminescence measurements. These tools were applied to the determination of hypochlorite in Dakin solution samples by chemiluminescence exploiting the oxidation of luminol by hypochlorite. An analytical procedure for salbutamol determination, exploiting the inhibition of chemiluminescence of luminol oxidation by hypochlorite, was developed, characterizing as a promising alternative for the quantification of this pharmaceutical substance. In both applications, results were in agreement to those obtained by reference procedures at the 95% confidence level

Soluções higienizadoras podem acarretar efeitos prejudiciais para as próteses, como deterioração da base da prótese e pigmentação. Porém, pouco se conhece sobre os efeitos destas na vida útil dos sistemas de retenção de uma overdenture. Deste modo, este estudo buscou avaliar se imersões diárias em clorexidina 2%, hipoclorito de sódio 1%, Corega® Tabs e água (controle) poderia acelerar a perda de retenção em attachments do tipo o´ring (S.I.N sistema de implantes®). Foram confeccionados 40 corpos de prova contendo cápsulas com anéis de borracha, simulando uma overdenture, e apenas 01 contendo o implante com o pilar o´ring. Eles foram separados em quatro grupos (n=10) e simulados noventa dias de imersões. Após, foram realizados testes de resistência à tração em uma máquina de ensaios mecânicos (MTS 810), antes e após a ciclagem com 270 ciclos, equivalentes a remoção e inserção da prótese três vezes ao dia, durante um período de três meses. Os resultados foram avaliados estatisticamente através dos testes ANOVA a dois critérios e do teste de Tukey (p≤0.05). Os valores médios (Newton) encontrados antes e após a imersão foram, respectivamente: Água - 9,482 / 6,081; Clorexidina - 9,972 / 7,390; Hipoclorito: 6,954 / 6,265 e Corega® Tabs: 12,464 / 11,121. Entre os grupos Clorexidina, Hipoclorito de sódio e Água não houve diferenças significativas. Houve diferenças estatisticamente significativas entre o grupo Corega® Tabs e os grupos controle e Hipoclorito de sódio, mas não com a Clorexidina. Assim, pôde-se concluir que soluções higienizadoras tiveram efeitos significativos na capacidade de retenção dos o´rings após o período simulado de três meses de imersão. / Denture cleansers can cause adverse effects on the prostheses, as deterioration of the denture base and pigmentation. However, little is known about its impacts on the life of an overdenture retention systems. Thus, this study sought to evaluate whether daily immersion in chlorhexidine 2%, sodium hypochlorite 1%, Corega® Tabs and water (control) would increase the retention loss in the O-ring type attachments (SIN implantes® system). Forty specimens containing capsules were made with rubber rings, simulating an overdenture, and only one containing the implant with the O-ring abutment. They were divided into four groups (n = 10) and ninety days in immersion were simulated, thereafter, conducted tensile strength tests on a testing machine (MTS - 810) before and after cycling of 270 cycles, equivalent to removal and insertion of the prosthesis three times a day for a period of three months. The results were statistically evaluated by the ANOVA two criteria and the Tukey test (p≤0.05). The mean values (Newton) found before and after immersion were: Water - 9,482 / 6,081; Chlorhexidine - 9,972 / 7,390; Hypochlorite: 6,954 / 6,265 and Corega® Tabs: 12.464 / 11.121. Among the groups chlorhexidine, sodium hypochlorite and water there were no significant differences. There were statistically significant differences between the group Corega® Tabs and controls and sodium hypochlorite groups, but not with the chlorhexidine. Thus, it concluded that denture cleansers had significant effects on retention capacity of orings after the simulated period of three months of immersion.

O objetivo deste trabalho foi avaliar, por meio de estudo laboratorial e clínico, a eficácia de soluções de hipoclorito alcalino (0,25% e 0,5%) e à base de mamona (Ricinus communis) a 10% quanto à ação antimicrobiana frente a micro-organismos específicos, por meio da contagem de Unidades Formadoras de Colônias (UFC). No estudo laboratorial, a partir de matrizes metálicas quadrangulares (10 x 2 mm), foram confeccionados 360 corpos de prova de resina acrílica termopolimerizável (Lucitone 550), os quais foram esterilizados em micro-ondas (650W, por 6 minutos), contaminados com cepas de Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Bacillus subtilis, Escherichia coli, Streptococcus mutans, Enterococcus faecalis e Candida glabrata e imersos (20 minutos) em soluções higienizadoras (n=10): Grupo A - Hipoclorito de sódio 0,25%; Grupo B - Hipoclorito de sódio 0,5%; Grupo C - Solução de mamona a 10%; Grupo D (Controle positivo) - solução salina e Grupo E (Controle negativo) - sem contaminação e imerso em solução salina (n=5). Em seguida, foram lavados em solução salina e imersos em meio de cultura líquido (Letheen), a partir do qual foram obtidas diluições seriadas (100 e 10-3), as quais foram semeadas em meios de cultura seletivos. Após incubação a 37ºC por 24 horas, as colônias foram contadas e os valores de UFC/mL calculados. No estudo clínico, 64 pacientes, usuários de próteses totais, foram orientados a escovar suas próteses (escova Bitufo® e sabonete líquido neutro) três vezes ao dia e imergí-las (20 minutos), uma vez ao dia, em soluções: Solução 1 - Hipoclorito de sódio 0,25%; Solução 2 - Hipoclorito de sódio 0,5%; Solução 3 - Solução de mamona a 10% e Solução 4 - solução salina (controle). De acordo com uma sequência aleatorizada, cada solução foi utilizada por 7 dias, com um período de wash out entre elas. A avaliação da ação antimicrobiana foi realizada antes dos uso dos produtos (Baseline) e após os 7 dias de uso de cada uma das soluções, por meio da contagem de Unidades Formadoras de Colônias (UFC) de Streptococcus mutans, Candida spp. e gram negativos. Para coleta do biofilme, cada prótese total superior foi colocada em placa de Petri e a superfície interna escovada (escova Tek e solução salina) por 2 minutos, sendo a suspensão transferida para tubo de ensaio. Após diluições decimais (100 até 10-3), alíquotas de 50 &mu;L foram semeadas em placas de Petri contendo Mitis Salivarius Agar Base, Chromagar® Candida e Mac Conkey Agar para a detecção de Streptococcus mutans, Candida spp. ou gram negativo, respectivamente. Após incubação a 37ºC (em microaerofilia durante 48-72 horas para grupo mutans e aerobiose durante 48 horas para Candida spp. e gram negativo), de acordo com morfologia típica, o número de colônias características foi mensurado e o número de UFC/mL calculado. Os dados obtidos foram transformados de acordo com a fórmula log10 (UFC+1) e analisados estatisticamente por meio do teste t de Student (&alpha;=0,05), para a análise laboratorial, e teste de Friedman (&alpha;=0,05), para a análise clínica. Os resultados mostraram que, no estudo laboratorial, as soluções de hipoclorito de sódio (0,25% e 0,5%) eliminaram completamente todos os micro-organismos. A solução de mamona eliminou completamente B. subtilis, não apresentou efeito sobre E. faecalis e apresentou ação antimicrobiana moderada frente às demais cepas, havendo redução significante (p < 0,05) do número de UFC quando comparado com o grupo D (controle positivo). No estudo clínico, houve diferença significante entre as soluções (P < 0,001), sendo que o hipoclorito de sódio a 0,5% apresentou ação efetiva sobre todos os micro-organismos avaliados (Candida spp., S. mutans e gram negativos); o hipoclorito de sódio 0,25%, ação efetiva sobre S. mutans e moderada sobre Candida spp. e gram negativos, e a solução de mamona, ação efetiva sobre S. mutans e moderada contra Candida spp. A espécie de Candida mais frequentemente isolada foi C. albicans, seguida pelas espécies C. tropicalis e C. glabrata. Concluiu-se que a solução de hipoclorito de sódio 0,5% foi a mais efetiva, apresentando ação antimicrobiana sobre ambos os biofilmes (in vitro e in vivo), seguida pela solução de hipoclorito de sódio 0,25% que apresentou ação antimicrobiana sobre o biofilme in vitro e sobre S. mutans (biofilme in vivo). A solução de mamona (10%) foi a menos efetiva, apresentando ação antimicrobiana sobre B. subtilis (biofilme in vitro) e S. mutans (biofilme in vivo). / The objective of this study was to evaluate, through laboratory and clinical study, the efficacy of alkaline hypochlorite solutions (0.25% and 0.5%) and 10% castor oil solution (Ricinus communis) about the antimicrobial action against specific microorganisms, by counting the number of Colony Forming Units (CFU). In the laboratory study, 360 denture base acrylic resin specimens (Lucitone 550) were obtained from square metal matrix (10 mm x 2 mm), which were sterilized with microwave (650W, for 6 minutes), contaminated with Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Bacillus subtilis, Escherichia coli, Streptococcus mutans, Enterococcus faecalis and Candida glabrata and immersed (20 minutes) in the hygiene solutions (n = 10): Group A - 0.25% Sodium Hypochlorite; Group - B - 0.5% Sodium hypochlorite; Group C - 10% Castor oil solution; Group D (Positive Control) - saline and Group E (Negative Control) - no contamination and immersed in saline (n = 5). The specimens were washed in saline solution and immersed in liquid culture medium (Letheen), from which were obtained serial dilutions (100 to 10-3) and seeded into selective solid media. After incubation at 37º C for 24 hours, the colonies were counted and the values of CFU/mL calculated. In the clinical study, 64 complete denture wearers were instructed to brush their dentures (Bitufo ® brush and liquid neutral soap) three times a day and to soak them (20 minutes), once a day, in the solutions: Solution 1 - 0.25% Sodium Hypochlorite; Solution 2 - 0.5% Sodium hypochlorite; Solution 3 - 10% Castor oil and Solution 4 - saline (control). According to a randomized sequence, each solution was used for 7 days, with a period of wash out between them. The evaluation of the antimicrobial action was performed before the use of the products (Baseline) and after 7 days after using each solution, by counting the Colony Forming Units (CFU) of Streptococcus mutans, Candida spp. and gram negative. For collection of the biofilm, each upper complete denture was placed in a Petri dish, the internal surface was brushed with saline solution for 2 minutes and the suspension was transferred to a test tube. After decimal dilutions (100 to 10-3), aliquots of 50 uL were seeded inside Petri dishes containing Mitis Salivarius Agar Base, Candida Chromagar ® and Mac Conkey Agar for the detection of Streptococcus mutans, Candida spp. or gram negative, respectively. After incubation at 37° C (in microaerophilic conditions for 48-72 hours for mutans and aerobiosis for 48 hours for Candida spp. and gram negative), in accordance with characteristic morphology, the number of characteristic colonies was countedand the number of CFU/ml calculated. Data were processed following transformation into the formula log10 (CFU +1) and statistically analyzed using the Student t test (&alpha; = 0.05) for laboratory analysis, and Friedman test (&alpha; = 0.05), for clinical analysis. The results showed that, in the laboratory study, sodium hypochlorite (0.25% and 0.5%) eliminated completely all microorganisms. The Castor oil solution eliminated B. subtilis, had no effect on E. faecalis and showed moderate antimicrobial activity against other strains, with a significant reduction (p <0.05) in the number of CFU compared with group D (positive control). In the clinical study, there was significant difference between the solutions (P <0.001), and 0.5% sodium hypochlorite had effective action on all evaluated microorganisms (Candida spp., S. mutans and gram negative); 0.25% sodium hypochlorite had effective action on S. mutans and moderate on Candida spp. and gram negative, and the castor oil solution had effective action on S. mutans and moderate against Candida spp. . The Candida species most often isolated was C. albicans, followed by the species C. tropicalis and C. glabrata. It was concluded that the solution of 0.5% sodium hypochlorite was the most effective presenting antimicrobial action on both biofilms (in vitro and in vivo), followed by 0.25% sodium hypochlorite solution that showed antimicrobial activity on biofilms in vitro and on S. mutans (biofilm in vivo). The 10% castor oil was less effective, with antimicrobial action on Bacillus subtilis (biofilm in vitro) and S. mutans (biofilm in vivo).

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-02T18:10:09Z No. of bitstreams: 1 tatianadiascosta.pdf: 1327074 bytes, checksum: 1b54c16084ca39ba9080752f52aa5c43 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-03T15:35:41Z (GMT) No. of bitstreams: 1 tatianadiascosta.pdf: 1327074 bytes, checksum: 1b54c16084ca39ba9080752f52aa5c43 (MD5) / Made available in DSpace on 2016-06-03T15:35:41Z (GMT). No. of bitstreams: 1 tatianadiascosta.pdf: 1327074 bytes, checksum: 1b54c16084ca39ba9080752f52aa5c43 (MD5) Previous issue date: 2014-08-29 / Neste estudo foi testada a hipótese de que instrumentos endodônticos fabricados com a liga de NiTi com tratamento térmico M-Wire são mais resistentes à corrosão em solução de NaOCl. Avaliou-se, por ensaio de polarização potenciodinâmica, a resistência à corrosão de 14 limas de NiTi sem tratamento de superfície (ProTaper® Universal Finishing 2 – F2, n = 7 e Mtwo® 25.07, n = 7) e de 14 limas de NiTi com tratamento de superfície (Reciproc® R25 25.08, n = 7 e Wave- One® Primary 25.08, n = 7), quando imersas em solução irrigante de NaOCl a 5,25%. Em miscroscópio eletrônico de varredura, as micromorfologias das 28 limas testadas foram analisadas antes e após o ensaio eletroquímico. As curvas de polarização anódica foram obtidas com potencial de varredura que iniciou no Ecorr de cada lima, com uma taxa de 0,333 mV/segundos (1,2 V/hora) até os Epite, sendo considerada como faixa passiva, a região onde os valores de potencial tinham densidade de corrente inferior a 10-5 A/cm2. A fim de se comparar as médias dos grupos aos pares foi empregada a prova não paramétrica de Mann-Whitney, utilizando-se o software estatístico SPSS-15 e o nível de significância adotado foi de p < 0,05. As curvas de polarização anódica demonstraram que todas as limas testadas foram passíveis de corrosão na solução de NaOCl a 5,25% (pH = 6,5). Observou-se que, no geral, apenas entre as limas Mtwo® (sem tratamento térmico) e Reciproc® (com tratamento térmico) não houve diferença estatisticamente significante para Epite ECS e Epite-Ecorr (p = 1,000). Ao se comparar, aos pares, as limas sem tratamento térmico (ProTaper® Universal F2 e Mtwo®) com as limas com tratamento térmico (Reciproc® e Wave-One®) não houve diferença estatisticamente significante (Ecorr ECS, p = 1,000; Epite ECS, p = 0,265; Epite-Ecorr, p = 0,265). A lima Reciproc® foi a que se apresentou mais resistente à corrosão e a ProTaper® foi a lima que mais sofreu corrosão na solução testada. Assim, a hipótese inicial de que instrumentos endodônticos fabricados com a liga de NiTi com tratamento térmico MWire são mais resistentes à corrosão em solução de NaOCl foi negada. / This study tested the hypothesis that endodontic instruments manufactured with the NiTi alloy heat treated M-Wire are more resistant to corrosion in NaOCl solution. Was evaluated by potentiodynamic polarization test, the corrosion resistance of NiTi files 14 without surface treatment (Universal ProTaper® Finishing 2 - F2, n = 7 and Mtwo® 25.07, n = 7) and 14 files NiTi with surface treatment (R25 Reciproc® 25.08, n = 7 and Primary Wave-One® 25.08, n = 7), when immersed in irrigating solution of NaOCl 5.25%. In electronic scanning microscopy, the micromorfologies of 28 tested files analyzed before and after the electrochemical test. The anodic polarization curves obtained by scanning the potential Ecorr that initiated in each file with a rate of 0.333 mV/sec (1.2 V/minute) to the Epite, being considered passive track, the region where the values potential had density of less than 10-5 A/cm2 current. In order to compare the averages of the groups in pairs used to non-parametric Mann-Whitney test, using the SPSS-15 statistical software and the significance level was p < 0.05. The anodic polarization curves show that all tested files are liable to the corrosion solution of 5.25% NaOCl (pH = 6.5). It was observed that, in general, only between Mtwo® (without heat treatment) and Reciproc® (heat treated) files there was no statistically significant difference for Epite ECS and Epite- Ecorr (p = 1.000). When comparing in pairs, the files without heat treatment (ProTaper® Universal F2 and Mtwo®) with files with heat treatment (Reciproc® and Wave-One®) there was no statistically significant difference (Ecorr ECS, p = 1.000; Epite ECS, p = 0.265; Epite-Ecorr, p = 0.265). The Reciproc® file introduced more resistant to corrosion and the ProTaper® was the file that suffered most corrosion in the tested solution. Thus, the initial hypothesis that endodontic instruments manufactured with the NiTi heat treated M-Wire are more resistant to corrosion in a solution of NaOCl was refused.

>Magister Scientiae - MSc / To address the urgent need for safe potable water in South Africa’s rural areas, sustainable systems for water disinfection at the village-scale of operation are required.In this thesis, the development of a small-scale water chlorination system that runs on salt and solar panels is described. The system combines a membrane-based hypochlorite generator, or “membrane electrolyser”, with an automated hypochlorite dosing system.The system was designed to (i) coordinate hypochlorite production and dosing automatically in a flow-through system, and (ii) fit inline with low pressure pipelines from overhead storage tanks or raised water sources. Low cost materials were used for construction, and water-powered mechanisms were devised to control both brine supply to the electrolyser and regulation of water flow. The capacity of the system was based on the maximum daily output of the electrolyser at ~20 g of sodium hypochlorite. This was sufficient chlorinate up to 10 kL of water per day using less than 80 g of salt and less than 0.1 kW.h of electricity. The cost of the system was estimated at ~R10 000 and therefore potentially affordable for communities up to 100 people, e.g. small farms and villages.Testing of the system was carried out at a farm site in Worcester (Western Cape) using remote monitoring of current levels in the electrolyser. Operation of the system over a two month test period, dosing at ~4 mg/L, produced consistent chlorination measured as(FAC). Community participation in maintenance of the brine supply was managed and chlorinated water was made available to the community after a brief social survey was conducted. Community awareness of chlorination was minimal. No significant history of diarrhoea was reported. However, the community regularly boiled their tap water in response to turbidity increase in summer.The system was affected by turbidity increase in the local water, which caused a drop in electrolyser current and chlorine production due to particle blockage of the membrane in the electrolyser. However, turbidity at acceptable levels for chlorination was found to have no detrimental effect on the system’s performance. The system showed promise for rural implementation providing low turbidity was maintained. Therefore,groundwater sites, and surface waters with appropriate clarification systems are recommended for the system’s installation. Further testing of the system will be required to establish its long term viability in the hands of a rural community.

Poor sanitation, unhygienic practices and close living associations between people and animals in rural communities increase the risk of zoonoses and add to faecal contamination of stored drinking water. Point-of-use interventions can improve the microbiological quality of household drinking water and a combination of microbial and chemical indicator tests could identify the origin of faecal pollution. The improvement of the microbiological quality of drinking water in rural households by the implementation of intervention strategies which included the use of traditional storage containers as well as an improved safe storage container (CDC, USA), with or without the addition of a sodium hypochlorite solution were determined. The origin of faecal contamination in the water sources and household stored water were determined using male specific F-RNA subgroup genotyping. This study attempted to assess the survival of indicator microorganisms and selected bacterial pathogens and viruses in the improved safe storage container in borehole and river water samples. An intervention study was conducted in two rural villages utilising different source water. Results indicated that the improved safe storage container without the addition of a stabilized sodium hypochlorite solution did not improve the microbiological quality of the stored drinking water and had counts of indicator microorganisms similar to that found in the traditional storage containers. However, the households using the 1% and the 3.5% sodium hypochlorite solutions have shown an effective reduction in the counts of indicator microorganisms in both the traditional and the improved safe storage containers. The compliance with the use of the sodium hypochlorite interventions ranged between 60% and 100%, which was in agreement with similar studies carried out in other developing countries. One village complied with the intervention while the other village did not. Reasons for this included financial factors, an unsupportive infrastructures and lack of education and knowledge on health risks by the households. Male specific F-RNA bacteriophage genotyping showed that faecal contamination in the water source samples and both the traditional and improved safe storage containers at the point-of-use were primarily of animal origin (Subgroup I). Households using river water had subgroup II F-RNA bacteriophages present in the stored household water, which was associated with human faecal pollution. However, subgroup II F-RNA bacteriophages has been isolated from faeces of cattle and poultry, which indicated that F-RNA subgroup typing might not be a specific tool to determine the origin of faecal pollution in water sources. Laboratory seeding experiments indicated that 1% sodium hypochlorite solution were less effective in reducing heterotrophic bacteria, Escherichia coli, Salmonella typhimurium, Clostridium perfringens, F-RNA bacteriophages and coxsackie B1 virus counts in the improved safe storage containers filled with river water with a high turbidity. However, the 1% sodium hypochlorite solution did reduce the indicator and seeded microorganisms within 60 min in containers filled with borehole water with a low turbidity. The 3.5% sodium hypochlorite solution effectively decreased the numbers of microorganisms to undetectable limits within 60 min in both the borehole and river filled storage containers irrespective of the turbidity values. This study has showed that a combination of intervention strategies can provide rural communities with microbiologically safe drinking water. / Thesis (PhD (Medical Virology))--University of Pretoria, 2008. / Medical Virology / PhD / unrestricted

In this work an epitaxial layer of Indium Phosphide (InP) has been grown on top of a silicon substrate using the Corrugated Epitaxial Lateral Overgrowth (CELOG) technique. The grown InP CELOG top layer typically has a poor surface roughness and planarity. Before this surface can be used for any processing it has to be smooth and planarized. For this purpose a two-step Chemical Mechanical Polishing (CMP) technique has been investigated and developed. In the first step commercially available Chemlox has been used to planarize the sample. In the second step Citric Acid (CA) and sodium hypochlorite (NaClO) has been mixed together to form abrasive-free polishing slurry. The second step has been developed to remove defects introduced by the first step. This surface is prepared to demonstrate that a photonic device such as a quantum well can be realized in a Photonic Integrated Circuit (PIC). A quantum well was grown on the polished CELOG InP/Si sample and measured with Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Photoluminescence (PL). The roughness was improved with CMP from 33.2 nm to 12.4 nm. However the quantum well did not give any response in the PL measurements. / I detta arbete har ett epitaxiellt lager indiumfosfid (InP) blivit växt på ett kiselsubstrat med hjälp av en korrugerad epitaxial lateral överväxt (CELOG) teknik. Det översta lagret av den CELOG växta ytan har ofta en väldigt ojämn yta. Innan denna yta kan användas till någon fortsatt utveckling måste den vara slät och plan. Det översta lagret har polerats med hjälp av en två-stegs kemisk mekanisk polerings (CMP) teknik. I det första steget har komersiellt tillgänglig Chemlox använts för att planarisera ytan. I det andra steget har citronsyra (CA) och natrium hypoklorit (NaClO) blandats samman för att bilda ett partikelfritt polermedel. Det andra steget har tagits fram för att ta bort defekter introducerade I det första steget. Ytan är preparerad för att demonstrera att en fotonisk enhet, t.ex. en kvantbrunn kan realiseras I en fotonisk integrerad krets (PIC). En kvantbrunn växtes fram på det polerade CELOG InP/Si provet och mattes med hjälp av atomkraftsmikroskop (AFM), scanning electron mikroskopi (SEM), röntgendiffraktion (XRD) och fotoluminisens (PL). Ytojämnheten förbättrades med hjälp av CMP från 33.2 nm till 12.4 nm. Dock så gav ej kvantbrunnen någon respons I PL-mätningarna.

The disinfection of wastewater is not something that is currently in use at any wastewater treatmentplant in Sweden. The government has however stated some requirements for some wastewatertreatment plants to have a plan to implement disinfection in their treatment process, if asked.Therefore the goal of the project is to research if disinfection with sodium hypochlorite can beimplemented at Slottshagen wastewater treatment plant. There are several factors that will affect the efficacy of the disinfection of the wastewater. Firstly, thedisinfection process is dependent on the pH of the water solution. This is because the weakhypochlorous acid has better disinfection than the hypochlorite ion, and hypochlorous acid is presentthe most in the solution at pH 3-6. Another factor that is important to consider is the amounts ofnutrients present in the solution, since the chlorine oxidizes the nutrients rather than reacting with theorganisms in the solution. Some of the products from the oxidation of the nutrients are bad for bothhuman health and the environment. Also the temperature of the water and the concentration of thechlorine will affect the disinfection. Lastly, depending on which organism that is sought out to bedisinfected, the chlorine will have more or less effect on that particular organism. To research the chlorination effect, different additions of sodium hypochlorite were added to samplesolutions from the treatment plant and got to react in the solution for 5 minutes. Following thesamples were neutralized with ascorbic acid, and the amount of E. coli , coliform bacteria andintestinal enterococci were analyzed. The disinfection of the water during 1,5 minutes and at a shortertemperature were also analyzed. The results showed that the temperature, the contact time with thesolution and the concentration all are important factors to reach a proper disinfection, but the resultsalso showed that the amount of bacteria in the solution also is an aspect to take into considerationwhen treating wastewater. Finally, the considerations of disinfection of the wastewater with sodium hypochlorite is discussed.The point of addition of the chlorine was concluded to best be directly after the last chemicaltreatment step. When analysing if the disinfection would be possible, the disinfection was from theresults possible, but it was noticed that the results fluctuated a lot. The most probable reason why isbecause of the water quality. The water quality in general fluctuates regularly throughout the day, aswell as in between days of the week. Therefore throughout the disinfection process, the additions ofchlorine would need to be depending on several parameters, making the disinfection difficult toimplement. One solution to this could be to add a lot of chlorine to the bulk water at all times, but itwould cost too much if treating the water for a longer time, as well as it would be a higher risk to theenvironment. A solution to this problem could be to possibly neutralize the water before it is releasedas well, however when analyzing the cost of the ascorbic acid that was used as neutralization in thisproject, the cost to neutralize the water completely would be too high. Lastly it was discussed that theonly time disinfection of the wastewater would give any desirable results, is if the specific organismsthat are being sought out to be treated are bacteria or some viruses. If the particular organism that iswished to be treated is parasites, the disinfection with chlorine would not work.

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