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Kinetic Analyses Of The Effects Of Temperature And Light Intensity On Growth, Hydrogenm Production And Organic Acid Utilization By Rhodobacter CapsulatusSevinc, Pelin 01 June 2010 (has links) (PDF)
Effects of temperature and light intensity on photofermentative hydrogen production by Rhodobacter capsulatus DSM1710 by use of acetic and lactic acids as substrates were studied. Experiments were conducted at 20, 30 and 38oC incubator temperatures under light intensities in the 1500 &ndash / 7000 lux range. pH of the medium and quantity of hydrogen forming together with quantity of biomass, and
concentrations of acetic, lactic, formic, butyric and propionic acids in the medium were determined periodically. Growth took place and hydrogen was produced under all experimental conditions. Growth was found to increase with increase in
temperature but to decrease with increase in light intensity. Total hydrogen produced increased with light intensity up to 6000 lux at 20oC, 5000 lux at 30oC and 3000 lux at 38oC and decreased beyond these values. Medium temperature of about 30oC was found to be optimum for cumulative hydrogen. pH was found to increase slightly and almost all of lactic acid and most of acetic acid was consumed while formic, butyric and propionic acids were first formed and then consumed in the experiments. Growth data fitted well to the logistic model and hydrogen production data fitted well to the
Modified Gompertz Model. Lactic acid was found to be almost completely consumed by first order kinetics in early times. Consumption of acetic acid was found to follow zero order kinetics in the early times when lactic acid existed in the
system but the order shifted to one later when most of lactic acid was consumed.
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Etude pétrologique, structurale et géochronologique des formations cristallines du quart nord~est de la feuille SAINT-GABRIEL-de-BRANDON ( Province de Grenville; Bouclier Canadien)Goulet, Normand 18 June 1971 (has links) (PDF)
La région de Saint-Gabriel-de-Brandon se situe à une centaine de kilomètres au NE de Montréal. Le secteur étudié couvre une superficie approximative de 125 km2 . Il comprend trois unités de roches cristallines précambriennes: un complexe migmatitique qui constituerait le socle de la région, une série paragneissique "de couverture", proche du Groupe de Grenville mais où les calcaires cristallins sont peu importants et enfin diverses roches plutoniques. Ces trois unités s'individualisent aussi bien du point de vue pétrographique que structural. Tout d'abord le complexe de base est composé de migmatites rubanées, (alternance de niveaux quartzo-feldspathiques et amphiboliques d'origine grauwackeuse) et de migmatites hétérogènes. A l'exception des amas et filons granitiques de ces dernières, les paragenèses sont celles du facies granulite. A l'intérieur de la "série paragneissique" qui se compose de gneiss alumineux, de gneiss à pyroxène, de quartzites, de roches calco-silicatées, de skarns et qui sont d'origine sédimentaire, sont interstratifiées, des leptites rubanées et des amphibolites d'origine éruptive ainsi que des gneiss à biotite et amphibole dérivant de formations volcano-détritiques. Les paragenèses de ces para et orthogneiss sont celles soit du facies amphibolite- almandin le plus élevé, soit du facies granulite. Leur apparition s'est faite à une température minimale de 670°C à une pression solide comprise entre 6 et 10 kb, la pression d'eau étant nettement inférieure à PS' Le granite adamellitique de Saint-Didace ainsi que les mangérites quartziques ortho-gneissifiées sont les types principaux des roches plutoniques qui sont en gros concordantes aux formations paragneissiques. L'étude structurale de la région a révélé la superposition de deux phases majeures de plissement. La première a produit des plis isoclinaux, d'ordre kilométrique, déversés vers le N ou le NO avec des axes orientés soit E-O, soit NE - SO. Les mangérites et sans doute le granite de Saint-Didace seraient à peu près synchrones de cette première phase. Au cours de celle-ci la série paragneissique se serait déversée vers le NO sur le complexe migmatitique qui aurait joué le rôle de socle. La deuxième phase, dont les plis sont axés entre NO - SE et N -S, a donné par superposition à la première, des figures d'interférence très complexes. Elle a affecté les trois ens embles mais les masses plutoniques ont agi comme des môles rigides à l' exception des "lames" relativement peu volumineuses de mangérites qui ont réagi aux efforts tectoniques comme leur encaissant. L'étude géochronologique effectuée sur ces ensembles tend à prouver la superposition de plusieurs orogenèses. L'orogenèse Grenvillienne (950 MA) a été obtenue sur le "mobilisat" du complexe migmatitique. Le granite de Saint Didace a sans doute été rajeuni à 1 105 MA. La série paragneissique aurait pour sa part été rajeunie durant l'orogenèse elsonienne (soit à 1 450 MA), tandis que la "restite" du complexe migmatitique de base donne un âge correspondant à l'orogenèse kénoranienne (2 300 MA).
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The role of cancer related inflammation, Src family kinases and matrix metalloproteinase 9 in colorectal cancerPowell, Arfon Gethyn Morgan Tregellis January 2016 (has links)
Colorectal cancer (CRC) is the third most common cancer in the UK with 41,000 new cases diagnosed in 2011. Despite undergoing potentially curative resection, a significant amount of patients develop recurrence. Biomarkers that aid prognostication or identify patients who are suitable for adjuvant treatments are needed. The TNM staging system does a reasonably good job at offering prognostic information to the treating clinician, but it could be better and identifying methods of improving its accuracy are needed. Tumour progression is based on a complex relationship between tumour behaviour and the hosts’ inflammatory responses. Sustained tumour cell proliferation, evading growth suppressors, resisting apoptosis, replicative immortality, sustained angiogenesis, invasion & metastasis, avoiding immune destruction, deregulated cellular energetics, tumour promoting inflammation and genomic instability & mutation have been identified as hallmarks. These hallmarks are malignant behaviors are what makes the cell cancerous and the more extreme the behaviour the more aggressive the cancer the more likely the risk of a poor outcome. There are two primary genomic instability pathways: Microsatellite Instability (MSI) and Chromosomal Instability (CI) also referred to as Microsatellite Stability (MSS). Tumours arising by these pathways have a predilection for specific anatomical, histological and molecular biological features. It is possible that aberrant molecular expression of genes/proteins that promote malignant behaviors may also act as prognostic and predictive biomarkers, which may offer superior prognostic information to classical prognostic features. Cancer related inflammation has been described as a 7th hallmark of cancer. Despite the systemic inflammatory response (SIR) being associated with more aggressive malignant disease, infiltration by immune cells, particularly CD8+ lymphocytes, at the advancing edge of the tumour have been associated with improved outcome and tumour MSI. It remains unknown if the SIR is associated with tumour MSI and this requires further study. The mechanisms by which colorectal cancer cells locally invade through the bowel remain uncertain, but connective tissue degradation by matrix metalloproteinases (MMPs) such as MMP-9 have been implicated. MMP-9 has been found in the cancer cells, stromal cells and patient circulation. Although tumoural MMP-9 has been associated with poor survival, reports are conflicting and contain relatively small sample sizes. Furthermore, the influence of high serum MMP-9 on survival remains unknown. Src family kinases (SFKs) have been implicated in many adverse cancer cell behaviors. SFKs comprise 9 family members BLK, C-SRC, FGR, FYN, HCK, LCK, LYN, YES, YRK. C-SRC has been the most investigated of all SFKs, but the role of other SFKs in cellular behaviors and their prognostic value remains largely unknown. The development of Src inhibitors, such as Dasatinib, has identified SFKs as a potential therapeutic target for patients at higher risk of poor survival. Unfortunately, clinical trials so far have not been promising but this may reflect inadequate patient selection and SFKs may act as useful prognostic and predictive biomarkers. In chapter 3, the association between cancer related inflammation, tumour MSI, clinicopathological factors and survival was tested in two independent cohorts. A training cohort consisting of n=182 patients and a validation cohort of n=677 patients. MSI tumours were associated with a raised CRP (p=0.003). Hypoalbuminaemia was independently associated with poor overall survival in TNM stage II cancer (HR 3.04 (95% CI 1.44 – 6.43);p=0.004), poor recurrence free survival in TNM stage III cancer (HR 1.86 (95% 1.03 – 3.36);p=0.040) and poor overall survival in CI colorectal cancer (HR 1.49 (95% CI 1.06 – 2.10);p=0.022). Interestingly, MSI tumours were associated with poor overall survival in TNM stage III cancer (HR 2.20 (95% CI 1.10 – 4.37);p=0.025). In chapter 4, the role of MMP-9 in colorectal cancer progression and survival was examined. MMP-9 in the tissue was assessed using IHC and serum expression quantified using ELISA. Serum MMP-9 was associated with cancer cell expression (Spearman’s Correlation Coefficient (SCC) 0.393, p<0.001)) and stromal expression (SCC 0.319, p=0.002). Serum MMP-9 was associated with poor recurrence-free (HR 3.37 (95% CI 1.20 – 9.48);p=0.021) and overall survival (HR 3.16 (95% CI 1.22 – 8.15);p=0.018), but tumour MMP-9 was not survival or MSI status. In chapter 5, the role of SFK expression and activation in colorectal cancer progression and survival was studied. On PCR analysis, although LYN, C-SRC and YES were the most highly expressed, FGR and HCK had higher expression profiles as tumours progressed. Using IHC, raised cytoplasmic FAK (tyr 861) was independently associated with poor recurrence free survival in all cancers (HR 1.48 (95% CI 1.02 – 2.16);p=0.040) and CI cancers (HR 1.50 (95% CI 1.02 – 2.21);p=0.040). However, raised cytoplasmic HCK (HR 2.04 (95% CI 1.11 – 3.76);p=0.022) was independently associated with poor recurrence-free survival in TNM stage II cancers. T84 and HT29 cell lines were used to examine the cellular effects of Dasatinib. Cell viability was assessed using WST-1 assay and apoptosis assessed using an ELISA cell death detection assay. Dasatinib increased T84 tumour cell apoptosis in a dose dependent manner and resulted in reduced expression of nuclear (p=0.008) and cytoplasmic (p=0.016) FAK (tyr 861) expression and increased nuclear FGR expression (p=0.004). The results of this thesis confirm that colorectal cancer is a complex disease that represents several subtypes of cancer based on molecular biological behaviors. This thesis concentrated on features of the disease related to inflammation in terms of genetic and molecular characterisation. MSI cancers are closely associated with systemic inflammation but despite this observation, they retain their relatively improved survival. MMP-9 is a feature of tissue remodeling during inflammation and is also associated with degradation of connective tissue, advanced T-stage and poor outcome when measured in the serum. The lack of stromal quantification due to TMA use rather than full sections makes the value of tumoural MMP-9 immunoreactivity in the prognostication and its association with MSI unknown and requires further study. Finally, SFK activation was also associated with SIR, however, only cytoplasmic HCK was independently associated with poor survival in patients with TNM stage II disease, the group of patients where identifying a novel biomarker is most needed. There is still some way to go before these biomarkers are translated into clinical practice and future work needs to focus on obtaining a reliable and robust scientific technique with validation in an adequately powered independent cohort.
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Pathophysiological mechanisms of absence epilepsy : a computational modelling studyDervinis, Martynas January 2016 (has links)
A typical absence is a non-convulsive epileptic seizure that is a sole symptom of childhood absence epilepsy (CAE). It is characterised by a generalised hyper-synchronous activity (2.5-5 Hz) of neurons in the thalamocortical network that manifests as a spike and slow-wave discharge (SWD) in the electroencephalogram. Although CAE is not a benign form of epilepsy, its physiological basis is not well understood. In an attempt to make progress regarding the mechanism of SWDs, I built a large-scale computational model of the thalamocortical network that replicated key cellular and network electric oscillatory behaviours. Model simulation indicated that there are multiple pathological pathways leading to SWDs. They fell into three categories depending on their network-level effects. Moreover, all SWDs had the same physiological mechanism of generation irrespective of their underlying pathology. They were initiated by an increase in NRT cell bursting prior to the SWD onset. SWDs critically depended on the T-type Ca2+ current (IT) mediated firing in NRT and higher-order thalamocortical relay cells (TCHO), as well as GABAB synaptic receptor-mediated IPSPs in TCHO cells. On the other hand, first-order thalamocortical cells were inhibited during SWDs and did not actively participate in their generation. These cells, however, could promote or disrupt SWD generation if they were hyperpolarised or depolarised, respectively. Importantly, only a minority of active TC cells with a small proportion of them bursting were necessary to ensure the SWD generation. In terms of their relationship to other brain rhythms, simulated SWDs were a product of NRT sleep spindle (6.5-14 Hz) and cortical δ (1-4 Hz) pacemakers and had their oscillation frequency settle between the preferred oscillation frequencies of the two pacemakers with the actual value depending on the cortical bursting intensity. These modelling results are discussed in terms of their implications for understanding CAE and its future research and treatment.
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Development and assessment of in vitro simulation approaches to intracerebral haemorrhageZarros, Apostolos January 2017 (has links)
This current PhD Thesis in Neuropathology focuses on the development and assessment of in vitro simulation approaches to intracerebral haemorrhage. The PhD Thesis provides a clinical and experimental neuropathological overview of intracerebral haemorrhage as well as an account of the in vitro simulation approaches to the disease, before proceeding to the presentation of the experimental work designed and performed by the author. The development of the herein presented in vitro simulation approaches to intracerebral haemorrhage was based on the use of an immortalized embryonic murine hippocampal cell-line (mHippoE-14) and its response to oligomycin-A and ferrum or haemin under appropriately selected conditions (aiming to simulate the natural history of the disease in a more reliable manner). The PhD Thesis provides a characterization of the mHippoE-14 cell-line (through a real-time cellular response analysis and a cytomorphological characterization), before proceeding to the actual experimental justification of the conditions chosen for the development of the herein presented in vitro simulation approaches to intracerebral haemorrhage, and their assessment. The latter was performed through the undertaking of: (a) real-time cellular response analysis, (b) cytomorphological assessment, (c) profiling of neuronal markers’ expression, (d) neurochemical assessment, and (e) proteomic profiling. All experiments were performed at the University of Glasgow. The current PhD Thesis also provides a critical appraisal of: (a) the utility, novelty and limitations of the developed in vitro simulation approaches, and (b) the positioning of the developed in vitro simulation approaches within the neuropathopoietic context.
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The impact of different dietary patterns on nutritional status and metabolic integrity in asymptomatic people living with HIV infection in South AfricaAnnan, Reginald Adjetey January 2009 (has links)
Adequate nutritional status promotes optimal structure and function. In PLWH, few studies on the impact of dietary intake on nutritional and metabolic status have been undertaken. This cross-sectional secondary data analysis examined how different dietary patterns influenced nutritional and metabolic integrity in asymptomatic PLWH in the North-West Province of South Africa. Dietary data were collected using validated QFFQ. Data analysis was by SPSS version 14. Dietary and nutrient patterns were generated using Principal Component Analysis. Though asymptomatic, marked biochemical differences depicting altered metabolism and inflammation were observed in PLWH compared to the uninfected. PLWH also showed an anthropometric profile that depicted altered body composition and abnormal fat distribution. Four dietary patterns: animal-based, ‘recommended’, staple, and the Carbohydrate, Vegetable and Legumes (CVL) based were observed in both PLWH and the uninfected with slight differences. In PLWH, the animal-based similar to the CVL pattern was associated with better overall nutrient intake (r=0.5, p<0.001) and selected nutrients, including energy (r=0.3, p<0.001), protein (r=0.6, p<0.001), iron (r=0.5, p<0.001), zinc (r=0.6, p<0.001) and vitamin A (r=0.5, p<0.001), compared to the other dietary patterns. The animal based dietary pattern also predicted higher BMI (OR=2.2, 95% CI=0.9-5.0), LBM (3.6, 1.3-10.4), serum albumin (1.5, 0.9-2.4) and lower liver enzymes AST (0.5, 0.3-0.8) and ALT (0.6, 0.4-0.9). Using Graphical Chain Modelling, higher intake of the animal-based but lower staple-based dietary patterns were associated with better overall nutrient intake, serum vitamins A, E, lipid score, albumin, BMI and LBM suggesting that intake of this diet may provide better nutrient quality, enhancing nutritional status and metabolic proficiency, which may ultimately influence disease progression. The findings have implications for dietary guidelines for this population but further research is required. However, if these findings are true, then a predominantly animal-based diet may be ‘recommended’ for this population. Moreover, the longer term implications of high fat intake associated with the animal based dietary pattern on obesity and associated risks should be considered. This poses a challenge to imperatively weigh up the longer term risks of the overall population profile crucial for public health.
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Decontamination of prions, prion-associated amyloid and infectivity from surgical stainless steel : implications for the risk of iatrogenic transmission of CJDHowlin, Robert January 2009 (has links)
The physicochemical nature of the infectious agent in prion diseases creates a significant challenge for decontamination services. It has been shown to be both resistant to standard methods of decontamination, used to inactivate viruses and bacteria, and to associate avidly with surgical stainless steel. Moreover, the pathophysiology of the variant, iatrogenic and sporadic forms of Creutzfeldt-Jakob Disease (CJD) suggests deposition of the infectious agent across a wide range of extraneural, lymphoid tissues, as well as in the skeletal muscle and blood. Coupled with the potential for asymptomatic carriers, there is a significant risk of iatrogenic transmission of CJD through both neurosurgical procedures and standard surgery. This PhD study was undertaken in order to improve methods of instrument decontamination and to evaluate prion detection techniques and their applicability for the assessment of prion inactivation and removal. The project has provided relevant, critical assessment of hospital decontamination procedures, in addition to guidance on how working protocols should be improved to provide a cleaner and safer end product for the patient. Moreover, laboratory studies have been performed to evaluate current methods of prion decontamination in the context of hospital procedures for instrument reprocessing. Challenges faced by sterile service departments, such as soil drying and surface degradation, have been addressed and their impact on the risk of iatrogenic transmission of prions has been investigated. Critically, the use of a fluorescent amyloid fluorophore for the detection of prionassociated amyloid as a marker for disease permitted the investigation of the role of amyloid in infectious disease under denaturing conditions. Correlation of this detection technique with the identification of PrPres by Western blot and infectious disease suggested that, whilst fluorescent detection of prion-associated amyloid was more sensitive than Western blot, PrPres detection was more specific relative to infectivity. Improved fluorophores, with greater sensitivity, have been evaluated which will enhance in situ detection of prions in the future.
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Quantifying crackles in the lung of smoking and non-smoking young adultsAlzahrani, Mohammed January 2011 (has links)
Crackle sounds are associated with a variety of lung disorders. Smoking is also associated with many of the changes in the lung and airways leading to crackles. However, studying crackles as an indication of pathologic changes related to cigarette smoking in the lung is an underdeveloped area of research which needs to be explored. This study was undertaken to investigate whether differences in the crackles' characteristics (duration of two cycle deflection (2CD) and number of crackles per breathing cycle (NCBC)) in the lung of smoking and non-smoking young adults could be found and to quantify these differences, if present, using a digital stethoscope and computer aided lung sound analysis (CALSA). Sixty male subjects (30 smokers and 30 non-smokers) with an average age of 26.6 years (SD ± 4.7) were recruited, drawn from students at the University of Southampton in the United Kingdom. The lung sound data were recorded on one occasion using a digital stethoscope connected to a laptop running MATLAB to record and store the lung sounds from seven anatomical sites on the chest. The 2CD and NCBC per site in 25 second recordings were calculated using data from each of the anatomical sites used for recording lung sounds (excluding the trachea). No statistically significant differences in NCBC per site were found between smokers and non-smokers at any anatomical location. The 2CD per site data revealed some statistically significant differences at both anterior sites (anterior left: F (2, 57) = 9.40, P = 0.00; anterior right: F (2, 57) = 9.51, P = 0.00)) and both lateral sites (middle left: F (2, 57) = 4.2, P = 0.02; middle right: F (2, 57) = 4.36, P = 0.02)). The hypothesis that lung crackle’s 2CD differ between smokers and non-smokers has been supported but the hypothesis that NCBC differ between smokers and non-smokers has not been supported.
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Mutability and survival of Pseudomonas aeruginosa in multi-species drinking water biofilm communitiesKennedy, Enyioha January 2012 (has links)
Pseudomonas aeruginosa is an important opportunistic pathogen of humans and also has the ability to form biofilms in drinking water. However, the survival, persistence and the control of this pathogen within mixed-species bacterial communities in drinking water distribution systems remains poorly understood. Strains of P. aeruginosa obtained from natural and pathogenic biofilms are often hypermutable due to defective DNA error repair systems. However, the role of mutation in determining survival and fitness of P. aeruginosa within the environment has not been explored. This work, investigated the mutability, persistence and survival of hypermutable mutS, wild type and environmental strains of P. aeruginosa within mixed species drinking water consortia and the effects of oxidative stress and water treatment practices including chlorination and UV irradiation on their mutability and persistence within these biofilms using a flow cell continuous culture system. Our results show that P. aeruginosa hypermutator strains integrated and persisted within the biofilm more readily than the wild type and environmental strains. Moreover, growth of P. aeruginosa within a multi-species biofilm led to a 5-fold increase in the mutation frequency (resistance to rifampicin, RifR) of the wild type strain compared to monospecies P. aeruginosa biofilms, suggesting that interactions within polymicrobial communities may promote genetic diversification. Our results also show that antioxidants (L-proline and N-acetyl-cysteine) had an average of 4-fold reduction effect in the mutation frequency of the wild type P. aeruginosa within the mixed species biofilms. However, the mutation frequency exhibited by the mutS strain within the biofilms is independent of oxidative stress. UV irradiation of P. aeruginosa cells, but not exposure to chlorine, led to increases in P. aeruginosa RifR mutation frequency and enhanced the persistence of surviving P. aeruginosa cells within drinking water biofilms. These findings therefore have provided new insights into mechanisms by which drinking water biofilms may harbour important pathogenic micro-organisms and how these interactions within the multispecies biofilms can enhance genetic adaptation and evolution of microbial pathogens.
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Estudo da OtimizaÃÃo do Processo H2O2/UV para degradaÃÃo do Corante Remazol Vermelho RB 133% / Study of the Process Optimization H2O2/UV for degradation of the dye Remazol Red RB 133%Jefferson Pereira Ribeiro 25 May 2011 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / As atividades industriais que consomem excesso de Ãgua no seu processo industrial, geralmente geram um elevado volume de efluentes, onde a indÃstria tÃxtil à um exemplo tÃpico. A oxidaÃÃo quÃmica à um dos processos alternativos para o tratamento de efluentes contendo corantes tÃxteis, entre eles destacam-se os POAs que sÃo baseados na geraÃÃo de radicais hidroxilas (.OH) no qual sÃo altamente oxidantes, podendo decompor compostos de maneira rÃpida e nÃo-seletiva, conduzindo a mineralizaÃÃo parcial ou completa do contaminante. O presente trabalho estudou o uso de processo oxidativo avanÃado para a degradaÃÃo do corante Remazol Vermelho RB 133%. Os estudos foram realizados em duas etapas. Na primeira etapa, no reator com 710 mL de volume Ãtil, foram realizados estudos de otimizaÃÃo dos parÃmetros: cinÃtica de descoloraÃÃo, dosagem do perÃxido de hidrogÃnio, pH, temperatura, adiÃÃo de perÃxido de hidrogÃnio em linha. A cinÃtica de descoloraÃÃo, e o efeito inibitÃrio de Ãnions tambÃm foram estudados. O estudo de cinÃtica mostrou que em 250 minutos houve uma descoloraÃÃo completa da soluÃÃo usando uma dosagem de perÃxido de hidrogÃnio de 1% H2O2 mediante o uso da radiaÃÃo UV. Nestas condiÃÃes houve uma remoÃÃo de 78,41% na DQO. O pH nÃo influenciou no processo de descoloraÃÃo da soluÃÃo, em contraste, para valores de pH iniciais 8 e 10 houve uma maior remoÃÃo na DQO. O estudo do efeito da temperatura do sistema mostrou que com o aumento temperatura a velocidade de descoloraÃÃo à pouco influenciada, ao passo que o aumento da temperatura (80ÂC) diminuiu a eficiÃncia do processo de remoÃÃo da DQO. A adiÃÃo de H2O2 em linha do processo aumentou a eficiÃncia na remoÃÃo de DQO. Os resultados das eficiÃncias de remoÃÃo ao final do processo indicaram que nÃo houve diferenÃa entre os tratamentos na presenÃa dos Ãnions na concentraÃÃo estudada (10 mM) quando comparada a degradaÃÃo sem a presenÃa desses Ãnions, pois ao final de todos os tratamentos a soluÃÃo ficou incolor. Na segunda etapa, no reator com 520 mL de volume Ãtil, foram realizados estudos de vazÃo e potÃncia de radiaÃÃo UV. O estudo mostrou que para as vazÃes estudadas 1,0; 2,0 e 3,0 L/min nÃo houve uma
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diferenÃa significativa no processo de descoloraÃÃo. As concentraÃÃes da matÃria orgÃnica ao final de 480 minutos de experimento para as trÃs vazÃes foram 36,63%; 51,08% e 48,35%, respectivamente. O aumento da potÃncia de radiaÃÃo UV proporcionou um aumento na eficiÃncia do processo de descoloraÃÃo e degradaÃÃo da matÃria orgÃnica. O estudo com efluente real mostrou uma baixa eficiÃncia na reduÃÃo de cor e de demanda quÃmica de oxigÃnio. / Industrial processes that consume excess of water, typically generates a high volume of effluent, where the textile industry is a typical example. The oxidation chemistry is one of the alternative processes for the textile dyes treatment. In this context, the Advanced Oxidation Processes (AOPs) are based on the generation of hydroxyl radicals (.OH) on which are highly oxidizing compounds can decompose quickly and non-selective contaminant solutes, for a partial or complete mineralization. This study investigated the use of advanced oxidation process for degradation of the dye Remazol Red RB 133%. The studies were conducted in two stages. For first step, in the reactor with 710 mL of working volume , were studies the parameters: kinetic effect, hydrogen peroxide dosage, temperature, pH, addition of hydrogen peroxide in the line. The kinetics study decolorization and the inhibitory effect of anions were also studied. The study of kinetic showed that in 250 minutes there was a complete decolorization of the solution using a H2O2 dose of 1% (v/v) through the use of UV radiation, and a 78.41% removal in Chemical Oxygen Demand (COD) was observed. The pH effect not influenced in the decolorization process; however has been influenced in removal of COD. The study of temperature effect showed that for an increase in temperature the decolorization rate increases, but a small improvement in the efficiency of COD removal. The addition of H2O2 during the process increased the efficiency of COD removal. The results of the efficiencies of the end of the process indicated that there was no difference between treatments in the presence of anions in the studied concentration (10 mM) when compared to degradation without the presence of these anions, since the end of all treatments, the solution was colorless. In the second stage, was carried in the reactor with 520 mL of working volume flow studies were performed and power of UV radiation. The studies of flow rate showed that for flow rate of 1.0; 2.0 and 3.0 L/min there was no significant difference in the process decolorization process. The of organic matter concentrations at 480 minutes of experiment for the three flow rates were 36.63%, 51.08% and 48.35% respectively. The increased power of UV radiation caused an increase in the
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efficiency of discolouration and degradation of organic matter. The study showed a real effluent with low efficiency to reduce color and chemical oxygen demand.
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