Line-induced chlorosis is a nutritional disease affecting many fruit trees, berries, ornamental shrubs, and flowers in Utah and the western United States. In fact, this disease is of wide distribution on calcareous soils throughout the world. Lime-induced chlorosis has contributed to untold economic loss and has challenged the technical ingenuity of plant and soil scientists throughout the world. As yet the exact cause of chlorosis has not been determined; consequently, no permanent cures have been found.

Indiana University-Purdue University Indianapolis (IUPUI) / For the past decade, many microfluidic paper-based analytical devices have been developed and used in different research fields. These devices are low-cost, portable, flexible, sterilizable, disposable, and easy to manufacture. The microfluidic paper-based analytical devices offer good alternatives to measurements and assays commonly performed in laboratories for analytical and clinical purposes, especially in diagnostics. In this work, we developed an electrochemical paper-based pH sensor. The determination of pH is essential in applications in areas as diverse as in the food industry, agriculture, health care or water treatment. The method presented in this work is an electroanalytical method that involves quantification of pH using stencil-painted graphite electrodes. Preliminary tests showed that pH can be determined on paper-based devices, thus indicating the presence of electroactive elements sensitive to pH on the surface of our electrodes (Chapter 4). Chemical modification of the electrode by adsorption with sodium carbonate and modification of the surface of the electrode was accomplished via: oxygen (ambient air) plasma treatment and pure oxygen plasma treatment. These treatments were to attempt to improve the definition of redox peaks on the CVs (Chapter 5). The changes made to the design of the paper-based device and the addition of a conditioning step improved the definition of the redox peaks on the CVs and increased the pH-sensing ability of our method (Chapter 6). The pH-sensing ability of our method was evaluated by testing solutions over a wide pH range. Adding sodium chloride to samples adjust the solution for accurate pH determination. The pH was successfully measured for solutions with values ranging from 1 to 13 and for artificial saliva samples prepared with pH values in the cavity-prone range (Chapter 7). This work offers a method that uses electroactive elements sensitive to pH on the surface of the PBD electrodes for pH-sensing.

This experiment was conducted to determine the differences in meat quality (cooking loss and shear force), descriptive sensory characteristics, consumer acceptance, and whole muscle proteomes between normal and Pale, Soft, and Exudative (PSE) broiler breast meat. Male Hubbard × Cobb 500 birds (n = 1,050) were raised in commercial houses. Prior to harvest, a sample of the broilers (n = 900) were subjected to short-term stress (38 °C for 2 h), and the remaining broilers (n = 150) were maintained at control conditions (21 °C for 2 h). From the stressed and control condition broilers, breast samples were characterized by pH24 and L*24 as normal (pH24 5.8-6.2, L*24 45-55) or PSE (pH24 5.4-5.7, L*24 55-65). Normal chicken breast meat had lower shear force values than PSE meat (P < 0.05). Based on sensory descriptive analysis, normal cooked chicken breast was more tender and juicier than PSE breast meat (P < 0.05). Consumer sensory analysis results indicated that 81% of consumer panelists liked normal breast meat whereas 62% of the panelists liked PSE breast meat. Whole muscle proteome profiling identified fifteen differentially abundant proteins (P < 0.05) in normal and PSE meat samples. Actin alpha, myosin heavy chain, phosphoglycerate kinase, creatine kinase M type, beta-enolase, carbonic anhydrase 2, proteasome subunit alpha, pyruvate kinase, and malate dehydrogenase were over-abundant in PSE meat whereas phosphoglycerate mutase-1, alpha-enolase, ATP-dependent 6-phosphofructokinase, and fructose 1, 6-bisphosphatase were over-abundant in normal meat. In addition, normal and PSE broiler breast meat were sampled from commercial plants and evaluated for meat quality attributes (pH, color, cooking loss, and tenderness) and their whole muscle proteome. Normal chicken breast meat had lower shear force values than PSE meat (P < 0.05). Proteome analysis revealed five differentially abundant proteins (P < 0.05) between the normal and PSE chicken breast samples. Glycolytic enzymes (beta-enolase and fructose-bisphosphate aldolase C) were over-abundant in PSE breast meat. Myofibrillar protein (myosin heavy chain) was over-abundant in PSE breast meat. In conclusion, results indicated that differences in proteome abundance could be related to the meat quality differences between normal and PSE breast meat.

Thiols are one of the most important classes of chemicals used broadly in organic synthesis, biological chemistry, and nanosciences. Thiol pKa values are key indicators of thiol reactivity and functionality. This study is an internally-referenced Raman-based pH titration method that enables reliable quantification of thiol pKa values for both mono- and di-thiols in water. The degree of thiol ionization is monitored directly using the peak intensity of the S-H stretching feature relative to an internal reference peak as a function of solution pH. The thiol pKa values and Raman activity relative to its internal reference were then determined by curveitting the experimental data with equations derived on the basis of the Henderson-Hasselbalch equation. Using this Raman titration method, first and second thiol pKa values for 1,2-benzenedithol in water were determined for the first time. This method is convenient to implement and its underlying theory is easy to follow.

In this thesis, the process involved in the precipitations and separations of the metal of Group II and Group III studied. Suggestions have also been offered whereby students can make an analysis without loosing metals in the initial precepitation.

Upset events due to the inflow of toxic chemicals are a critical issue for wastewater treatment facilities. Understanding the source-effect relationship of toxic chemicals can facilitate the prevention or improved reaction to upset events. Part one of this study was conducted to investigate the source of upset events at a regional industrial wastewater treatment plant (WWTP). Part two of this study determined the process performance effects of two chemical shocks, cyanide (zinc-cyanide complex) and pH, on nitrifying and non-nitrifying activated sludge. A modified respirometric assay protocol was developed to allow the industrial WWTP to screen industrial wastewaters for inhibitory properties. All five industrial wastewaters tested revealed inhibitory properties. Large day-to-day variations were found, illustrating the need for a large database of results for comparison over time. Additionally, a small volume contributor, that was thought by the utility to be an unlikely source of problems, contributed significantly to the wastewater oxygen demand and demonstrated inhibitory properties. The modified respirometric procedure enabled the WWTP to identify possible industrial sources that could cause an upset event. Lab-scale sequencing-batch reactors were used to determine the effects of cyanide and pH shock on activated sludge. Three reactors were shocked with increasing weak-acid complexed zinc cyanide or pHs of 5, 9, and 11. The resulting effects were compared to an un-shocked control reactor. It was found that respiration and nitrification were affected by the zinc cyanide complex, while COD removal, effluent TSS and dewaterability were not. Recovery was seen in less than 2 X solids residence time (SRT) for the nitrifying biomass and within 3 X SRT for the non-nitrifying biomass. The results of the pH experiment showed that the pH 11 shock affected the settleability, nitrification, COD removal, and effluent TSS levels of the reactors, while pH 5 and pH 9 shocks had no effect. Recovery was seen within 3 X SRT for both the nitrifying and non-nitrifying systems. / Master of Science

abstract: Vinegar is gaining popularity as a natural and proven treatment for common diseases and conditions ranging from high blood pressure to diabetes. While the evidence to support the benefits of vinegar is growing, few studies have considered possible negative consequences. One concern relates to the effect of vinegar on saliva pH and dental erosion. The aim of this study is to explore this relationship as well as unsubstantiated claims that vinegar, although acidic, has an alkalizing effect on the overall body, specifically looking at its effect on resting saliva pH. Healthy adults aged 18-45 were recruited for this trial. Twenty-two participants completed this eight-week, parallel-arm, randomized, double blinded study that looked at the effect that regular consumption of red wine vinegar (two tablespoons taken two times per day before a meal) had on resting salivary pH and dental erosion compared to a control (low dosage vinegar pill taken two times a day before a meal). Resting saliva pH was measured at home using the pH20H application and pH strips at week 0 and 8 of the trial. Erosion was noted using the Basic Erosive Wear Examination (BEWE) by a registered dental hygienist at week 1 and 8 of trial. Results indicate no mean difference in resting salivary pH in either treatment group after eight weeks (p value, 0.49). However, there was a statistical significant mean difference in dental erosion between the VIN and CON group (p value, 0.05). Statistical significance in dental erosion, typically a gradual process, in just eight weeks is a significant finding and warrants concern about long time use of vinegar and dental health. Further exploration into this relationship is needed. / Dissertation/Thesis / Masters Thesis Nutrition 2019

[pt] O pH constitui um dos parâmetros de controle de qualidade do etanol combustível, sendo estabelecido pela norma brasileira ABNT NBR 10891, cujo escopo é específico para etanol hidratado combustível, e pela norma americana ASTM D 6423, a qual o foco é o etanol anidro combustível. Neste contexto, o presente estudo apresenta uma análise crítica à composição dos eletrodos utilizados pelos diferentes sistemas de medições para pH de etanol, devido à presença de água na composição do eletrodo de vidro. Com isso, o objetivo do presente estudo consistiu em uma proposta de um novo sistema para medição de pH de etanol hidratado combustível, o qual foi o único solvente utilizado, empregando como referência indicadores ácido-base. Por meio do planejamento de experimentos Box-Behnken foi possível determinar a condição otimizada esperada para o novo sistema de medição, o qual foi comparado com os sistemas propostos pelos referenciais normativos e posteriormente com o intervalo de pH definido pelos indicadores. Os resultados revelaram que os valores de pH obtidos pelos diferentes sistemas utilizados, incluindo o proposto pelo presente estudo, são estatisticamente diferentes entre si, e que somente os valores obtidos pelo novo sistema de medição se adequa à faixa de pH encontrada pelos indicadores. O eletrodo otimizado apresentou uma sensibilidade de resposta adequada à equação de Nernst, tendo um comportamento operacional adequado ao novo sistema de medição proposto pelo presente estudo. / [en] The pH is one of the quality control parameters of fuel ethanol, established by the Brazilian standard ABNT NBR 10891, whose scope is specific for hydrated fuel ethanol, and by the American standard ASTM D 6423, which focuses on anhydrous ethanol fuel. In this context, the present study presents a critical analysis of the composition of the electrodes used by the different measurement systems for ethanol pH, due to the presence of water in the composition of the glass electrode. Thus, the objective of the present study was to propose a new system for measuring the pH of hydrated fuel ethanol, which was the only solvent used, using acid-base indicators as a reference. Box-Behnken Design made possible to determine the optimal condition expected for the new measurement system, which was compared with the systems proposed by the normative references and later with the pH range defined by the indicators. The results revealed that the pH values obtained by the different systems used, including the one proposed by the present study, are statistically different from each other, and that only the values obtained by the new measurement system are suitable for the pH range found by the indicators. The optimized electrode presented an adequate response sensitivity to the Nernst equation, having an operational behavior adequate to the new measurement system proposed by the present study.

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