Orientador: Claudio Airoldi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T02:05:09Z (GMT). No. of bitstreams: 1 Pinto_AlaneAzevedo_D.pdf: 17904137 bytes, checksum: 502a56cd671d10614a5c034a8a3cf22e (MD5) Previous issue date: 2010 / Resumo: Os ácidos silícicos magadeíta, kaneíta, e kanemita, com fórmula geral, Na2O(4-22)SiO2.(5-10)H2O, definem uma classe de compostos com arranjos lamelares distintos, cujas estruturas permitem não somente intercalações, como também reações de imobilização, uma vez que as propriedades físicas dos silicatos incluem uma elevada capacidade na troca de íons, sendo que o sódio pode ser substituído por próton, outros cátions ou íons amônio quaternários. As matrizes lamelares magadeíta, kaneíta e kanemita foram sintetizadas e tiveram a troca do cátion sódio por prótons, a fim de aumentar a reatividade das mesmas para efetivar processos de intercalação e imobilização. As matrizes sódicas também foram intercaladas com o surfactante brometo de cetiltrimetilamônio, CTAB, para expandir suas distâncias basais e permitir a incorporação de moléculas volumosas. Tais matrizes e suas formas modificadas foram utilizadas no processo de sorção de cátions metálicos, em solução aquosa, no qual os dados calorimétricos demonstraram que os processos são favoráveis na sorção, verificados através dos valores das grandezas termodinâmicas. Foram utilizadas, também, no processo de sorção de corantes de solução aquosa e na determinação da quantidade de aminas intercaladas. Os dados experimentais de sorção foram ajustados aos modelos de Langmuir, Freundlich e Temkin, no equilíbrio. As matrizes originais e intercaladas foram, então, caracterizadas pelas técnicas de difração de raios X, espectroscopia na região do infravermelho, ressonância magnética nuclear (RMN), termogravimetria e microscopia eletrônica de varredura. Os dados de raios X confirmaram o sucesso das intercalações, através do aumento das distâncias basais, devido à entrada de moléculas convidadas na cavidade interlamelar. Os espectros de RMN dos núcleos de carbono e silício no estado sólido comprovaram a incorporação dos agentes sililantes nas estruturas dos ácidos silícicos / Abstract: The silicic magadiite, kenyaite and kanemita acids with general formula, Na2O(4-22)SiO2.(5-10)H2O, defines a class of compounds with distint layered arrangements, whose structures permit not only intercalation, as well as immobilization reactions, which physical silicates properties include a high capacity in ion exchange properties, being sodium substituted by proton, other cations or quaternary ammonium ions. The lamellar magadiite, kenyaite and kanemite matrices were synthesized and had the sodium cation exchanged by protons, in order to increase the reactivity to execute the intercalation and immobilization processes. The sodic matrices were intercalated with cetyltrimetylammonium bromide, CTAB, with expansion of their basal distances and also to allow voluminous molecule incorporation. Such matrices and their modified forms had been used in the metallic sorption processes in aqueous solution, in which the calorimetric data demonstrated that these sorptions are favorable, after proving through the thermodynamic data. The same procedure was also used for dye sorption from aqueous solution and the determination of the amount of intercalated amines. The experimental data were adjusted to the Lamgmuir, the Freundlich and the Temkin models at equilibrium. The original and intercalated matrices had been, then, characterized by X-ray difractions, infrared spectroscopy, nuclear magnetic resonance (RMN), thermogravimetry and scanning electronic microscopy. The Xrays data confirmed the success of the intercalation through the increase of the basal distances, due to the entrance of invited molecule in the interlamelar cavity. The RMN spectra for carbon and silicon nuclei in the solid state demonstrated the incorporation of the silylating agents in the silicic acid structures / Doutorado / Quimica Inorganica

Made available in DSpace on 2014-10-09T12:29:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:41Z (GMT). No. of bitstreams: 1 01258.pdf: 2657988 bytes, checksum: af006c60c93b3785f8e6a1b4e10cd551 (MD5) / Thesis (Doctorate) / IEA/T / Darwin College, Cambridge, London

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The propagation of waves through nonlinear media is of interest here, namely as it pertains to two specific examples, a nonlinear dielectric and a hyperelastic solid. In both cases, we examine the propagation of two-dimensional, weakly nonlinear, quasi-planar waves. It is found that such systems will have a nonlinearity that is intrinsically cubic, and therefore, a classical Zabolotskaya-Khokhlov equation cannot give an accurate description of the wave evolution. To determine the general evolution equation in such systems, a multi-timing technique developed by Kluwick and Cox (1998) and Cramer and Webb (1998) will be employed. The resultant evolution equations are seen to involve only one new nonlinearity coefficient rather than the three coefficients found in other studies of cubically nonlinear systems. After determining the general evolution equation, inclusion of relaxation, dispersion and dissipation effects can be easily incorporated. / Master of Science

This thesis examines the effect of solids recycling on nitrification, organic carbon removal, and algal-bacterial productivity in bench-scale photobioreactors (PBRs) simulating winter pond conditions in San Luis Obispo, California and a 6-acre raceway system in Delhi, California. Two sets of duplicate photobioreactors operated with or without solids recycling were fed primary clarifier effluent (1oEff) for the first experiment, and facultative pond effluent (FAC) for the second experiment. In both experiments mean productivity was lower in solids recycled PBRs (3.67 and 2.3 g/m2-day), than in controls without solids recycling (4.15 and 3.9 g/m2-day). When fed 1oEff which contained a high amount of readily biodegradable COD, solids recycled PBRs had 30% less VSS in supernatant than controls after 1 hour of settling in Imhoff cones. However, when fed facultative pond water with no readily biodegradable COD there was little difference in supernatant VSS after settling. The type of wastewater influenced COD removal. PBRs had 40-50% soluble COD removal when fed 1oEff, and 10-20% removal when fed FAC. Mean PBR effluent COD was the same in both treatments and controls in when fed 1oEff (42 mg/L). When fed FAC mean effluent COD was marginally lower in solids recycled PBRs (61 mg/L) then in controls (68 mg/L). Most of the COD in 1oEff was readily biodegradable, while most of the COD in FAC was degraded while in facultative ponds leaving mostly recalcitrant and slowly biodegradable COD in FAC. Nitrification occurred more quickly and more reliably in solids recycled PBRs. The difference in nitrification was seen most notably when using FAC as PBR influent, where solids recycled PBRs had complete nitrification, but controls did not. When fed 1oEff all PBRs had complete nitrification, but solids recycled did so sooner. Overall, PBRs with solids recycling were also more resilient to changes in influent wastewater characteristics and had more consistent effluent water quality when fed wastewater that had occasional spikes in nitrogen and organic carbon. The difference between the two wastewaters indicates a possible inhibitory effect of FAC on nitrification. Microscopy data from both studies, though mostly qualitative, seems to indicate that solids recycling promotes biodiversity in algal-bacterial cultures, which may be part of the reason why solids recycling promoted more resilient and reliable treatment.

This study examines the wastewater treatment system on BillerudKorsnäs integrated pulpand paper mill at Karlsborg, with focus on the effluent of suspended solids. Due to lowerregulatory limits for the emissions of suspended solids BillerudKorsnäs is looking forways to improve the efficiency of the wastewater treatment. Therefore, this study seeksto create a statistical model for the emissions of suspended solids and to find which factorsin the production, wastewater treatment and surrounding environment that affects theemissions. The purpose of the study is to extend the current understanding of the treatmentsystem to create a base for future decisions. The methods used for the modelling areElastic net regression and Random forest classifier, which were selected for the variableselection properties they provide. Unfortunately, the results show that the fitted modelscan only explain a small part of the variation of the emissions of suspended solids.The lack of fit in the models indicate that the current data is not sufficient to explain thevariation in the emissions of suspended solids. During the study deficiencies in the datacollection has been detected and improvements to overcome these deficiencies are proposedin the hope of creating more reliable data for the company and to create a betterbasis for future studies. / Denna studie undersöker avloppsvattenreningen på BillerudKorsnäs integrerade massaoch pappersbruket i Karlsborg, med fokus på utsläppen av suspenderade ämnen. Pågrund ut av sänkta gränser för utsläppen av suspenderade ämnen undersöker BillerudKorsnäsmöjligheter för att öka effektiviteten i avloppsvattenreningen. Därför försöker dennastudie att skapa en statistisk modell för utsläppen av suspenderade ämnen och undersökavilka faktorer i produktion, avloppsvattenrening, och omgivande miljö som påverkar utsläppen.Syftet med studien är att förbättra förståelsen för avloppsvattenreningen och attskapa beslutsunderlag för framtida förbättringar. Metoderna som används i modellernaär Elastic net regression och Random forest classifier, vilka valdes för deras variabel selectionegenskaper. Resultaten för modellerna visar att modellerna endast kan förklara enliten del av variationen i utsläpp av suspenderade ämnen. Det dåliga resultatet indikeraratt nuvarande data inte är tillräckligt för att skapa den typ av modeller som används. Understudien så har brister i datainsamlingen upptäckts, och förbättringar för att överbryggadessa brister är föreslagna med ändamål att göra insamlad data mer pålitlig och skapa enbättre bas för framtida studier.

An investigation was carried out to study whether long-chain fatty acids (LCFAs) have an effect on digestion of waste sludge under anaerobic conditions. Four different kinds of LCFAs were used in this study. The 18 carbon series with 0, 1, 2 and 3 double bonds were studied to evaluate the degree of saturation on fatty acid degradation. Due to their molecular structure, unsaturated LCFAs are more soluble than saturated LCFAs. Oleic, linoleic, linolenic acid with an ascending number of double bonds were tested as representatives for three different degrees of saturation. In addition, stearic acid, a saturated fatty acid was also tested. LCFAs were added to sewage sludge at concentrations ranging from 5% to 20% on a weight basis and the pH, solids reduction and COD reduction were determined. The results suggested that in addition to degrading in the digesters, all unsaturated acids contributed additional solids removal, compared to the control group. In contrast, stearic acid did not affect the solids removal. The COD reduction was similar to solids reduction in that additional COD was destroyed when unsaturated LCFAs were added to the sludge. The mechanism for additional solids reduction is not known. / Master of Science

A process which incorporates whey sol ids, primarily protein, into cheese to increase cheese yield and eliminate whey handling problems was evaluated. Whey was concentrated by ultrafiltration to levels of 9.8 to 20.3 percent total solids (4.3 to 7.1 percent protein), heated at 70 C for 30 minutes and added to cheese milk with the coagulating enzyme. Increase in cheese yield, on the basis of 39 percent moisture, for 10 pairs of samples was 4.0 ± 2.8 (S.D.) percent. This increase was significant at alpha less than 0.001. Moisture and protein content increased while fat content decreased. Setting time and pH also decreased. Body/texture evaluation showed no change, but flavor scores decreased. Specific defects responsible for changes in flavor and body/texture were identified.