x, 123 leaves : photos., graphs, tables ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Physiology, Waite Agricultural Research Institute, 1977

Thesis (PhD)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The present study deals in the first instance with the improvement of current analytical techniques for the analysis of the non-volatile content of wines. An improved sample preparation method, using solid phase extraction (SPE), was initially developed for the analysis of organic acids, sugars and phenolic compounds. Consequently, modem analytical methodologies were assessed to obtain optimal techniques for the separation of various non-volatile compounds. A capillary electrophoresis (CE) method, demonstrably more reliable than currently used high performance liquid chromatography (HPLC) and CE methods, is proposed for the analysis of organic acids. HPLC with refractive index (RI) or evaporative light scattering detection (ELSD) proved more suitable than CE for the analysis of sugars in dry wines. Liquid-chromatography-mass spectroscopy (LC-MS) offered superior sensitivity and resolution compared to the relatively new technique of CE-MS for the analysis of wine phenolics. LC-MS was further applied for the efficient and sensitive analysis of non-coloured phenolics and anthocyanins in wine. Negative- and positive electrospray ionisation, respectively, were used in conjunction with an ion-trap mass analyzer, for the identification of 34 phenolics and 31 anthocyanins in red wine samples. Complementary CE and LC methods were developed to allow the identification of artificial dyes in red wines, added illegally to improve their colour. Also, the application of stir bar sorptive extraction (SBSE) with liquid desorption and micellar electrokinetic chromatography (MEKC) for the analysis of bitter acids in beer is reported. In the second part of the thesis, the analytical results obtained for South African red and white wines were evaluated. Following comparison of the results with literature reports, several pattern recognition techniques were employed. A classification function obtained by linear discriminant analysis (LDA) was used to classify both red and white wines according to variety, based on their chemical composition. This classification is achieved independent of the factors of wine age or geographical origin, making it useful for authenticity evaluation. / AFRIKAANSE OPSOMMING: Hierdie studie het as primêre doel die verbetering van bestaande analitiese metodes vir die analise van nie-vlugtige komponente in wyn. In die lig hiervan, is eerstens 'n toepaslike monster-voorbereidingstegniek, gebasseer op soliede fase ekstraksie (SPE), ontwikkel vir die gelyktydige analise van organise sure, suikers en fenoliese komponente vanuit die wyn matriks. Vervolgens is moderne analitiese rtietodes ondersoek en gepastde skeidingstegnieke is ontwikkel vir die verskillende chemiese wyn-komponente. Kappillêre elektroforese (CE) en hoë-druk vloeistof-chromatografie (HPLC) in kombinasie met verskeie deteksie-metodes is vergelyk. Hieruit is 'n verbeterde CE metode vir die analise van organise sure is ontwikkel, terwyl HPLC in kombinasie met refraksie-indeks- en verdampings lig verstrooiings deteksie (ELSD) die beste resultate lewer vir die analise van suikers in droë wyne. Die toepasbaarheid van vloeistof-chromatografie met massa spektrometriese deteksie (LC-MS) vir die analise van fenoliese komponente is gedemonstreer, terwyl CE-MS onvoldoende resolusie en sensitiwiteit toon vir die analises. LC-MS is vervolgens ook gebruik vir die identifikasie van 34 fenoliese verbindings en 31 antosianiede in rooi wyn. Komplementêre HPLC en CE metodes is ontwikkel vir die identifikasie van onwettige sintetiese kleurstowwe in' rooi wyn. 'n Addisionele monstervoorbereidingsstap, roerstaaf sorptiewe ekstraksie (SBSE), is saam met vloeistof-desorpsie en misellêre elektrokinetiese chromatografie (MEKC) gebruik vir die analise van hops bitter sure in bier. In die tweede deel van die tesis word die resultate verkry m.b.v. bg. tegnieke vir die analise van Suid-Afrikaanse rooi- en wit wyne, bespreek. Die resultate is vergelyk met waardes uit die literatuur, en verskeie statistiese metodes is gebruik om die data te ondersoek. Met behulp van chemometriese metodes is 'n klassifikasie funksie verkry wat die klassifikasie van Suid-Afrikaanse wyne volgens druifsoort, gebasseer op die chemiese samestelling van die wyne, toelaat. Die klassifikasie is moontlik, onafhanklik van die ouderdom of geografiese oorsprong van die wyne.

The following Master thesis is based on the technical language of recycling and plastic processing taking into consideration the relevant language and text attributes. Characteristic features are analysed on the basis of leaflets acquired at the international trade fair Fakuma focussing on this particular industry. First, the Master thesis concentrates on the definition of technical language itself presenting different points of view of this issue. Furthermore, the thesis focuses on the technical language of technology, chemistry and ecology which is employed in the analysed leaflets. Of major importance for the flyers is also the element of advertising which is elaborated in the second chapter. The empirical part of the thesis concentrates on a text analysis of each of the language subsystems: textual, stylistic, lexical and morphological. To conclude with, the thesis provides table overviews and a summarizing chapter.

Orientador: Márcia Cristina Bisinoti / Coorientador: Odair Pastor Ferreira / Coorientador: Camila de Almeida Melo / Banca: Etelvino Henrique Novotny / Banca: Maurício Boscolo / Resumo: Durante o processo de obtenção de açúcar e álcool são geradas quantidades elevadas de resíduos, tais como bagaço de cana-de-açúcar e vinhaça. Neste trabalho foi produzido hidrochar, utilizando a mistura bagaço de cana-de-açúcar e vinhaça, que possa ser empregado como fornecedor de nutrientes ao solo. Para tal, o processo de carbonização hidrotérmica (CHT) dos resíduos foi conduzido na presença de aditivos ácidos (H2SO4, H3PO4, H3BO3), básicos (NaOH, KOH) e salinos (FeCl2, (NH4)2SO4), em três temperaturas e tempo de reação fixo. Nos hidrochars foram determinados o rendimento em massa, teor de umidade, cinzas, matéria orgânica, e foram feitas as caracterizações por espectroscopia no infravermelho (FTIR), análise elementar (CHNS), difração de raios-X (DRX), microscopia eletrônica de varredura (MEV) e quantificação de nutrientes (K, Ca, P, Mg, B, Zn, Cu, Mn, Fe). As águas de processo geradas na CHT, foram caracterizadas quanto ao pH, cor, turbidez, condutividade elétrica, concentração de carbono orgânico total (COT) e concentração de nutrientes. Os resultados indicaram que na presença dos aditivos, principalmente do H3PO4e (NH4)2SO4, o rendimento do hidrochar aumentou à medida que o teor de cinzas aumentou devido à precipitação de fosfatos e sulfatos conforme observado por DRX. A temperatura de carbonização hidrotérmica teve influência no grau de carbonização dos hidrochars, os quais apresentaram maior teor de carbono na maior temperatura. O aumento da temperatura proporcionou... / Abstract: During the process of obtaining sugar and alcohol, high amounts of residues are generated, such as sugarcane bagasse and vinasse. This work proposes to produce hydrochar, using the sugarcane bagasse and vinasse mixture, which can be used as a supplier of nutrients to the soil. The hydrothermal carbonization process (HTC) of the residues was conducted in the presence of acidic (H2SO4, H3PO4, H3BO3), basic (NaOH, KOH) and saline (FeCl2, (NH4)2SO4) additives, at three temperatures and fixed reaction time. On the hydrochars was determined the mass yield, moisture content, ash, organic matter, and characterizations were made by Infrared spectroscopy (FTIR), elemental analysis (CHNS), X-ray diffraction (XRD) and scanning electron microscopy (SEM) and quantification of nutrients (K, Ca, P, Mg, B, Zn, Cu, Mn, Fe). The process water generated in the HTC were characterized as pH, color, turbidity, electrical conductivity, concentration of total organic carbon (TOC) and nutrient concentration. The results indicated that in the presence of the additives, mainly H3PO4 and (NH4)2SO4, the yield of the hydrochar increased as the ash content increased due to the precipitation of phosphates and sulphates as observed by XRD. The temperature of hydrothermal carbonization influenced the degree of carbonization of the hydrochars, which they presented higher carbon content at the higher temperature. The increase in temperature caused higher immobilization of Ca, Mg, K, Mn, Zn, B, P and Fe in all ... / Mestre

Nesta dissertação, o objetivo geral foi a elaboração e implementação de um projeto de gestão de resíduos (PGR) que permitisse minimizar e orientar para a destinação adequada dos resíduos gerados nas atividades experimentais de uma escola da rede pública de Porto Alegre que oferece o curso Técnico em Química (TQ). Para tanto, foi realizada uma investigação qualitativa, do tipo Estudo de Caso, onde após tratativas com a direção da escola, assim como com os professores do curso, verificou-se a presença de passivo ambiental e os hábitos adotados para o descarte dos resíduos gerados nas aulas experimentais de algumas disciplinas. As observações foram registradas em Diário de Campo. Na sequência foram aplicados questionários com docentes e discentes, para o diagnóstico das suas percepções sobre a elaboração e implementação de um PGR. Após a identificação das necessidades e do contexto escolar, foi elaborado o PGR para o TQ. Para que toda a comunidade escolar conhecesse o documento e pudesse adaptar suas práticas às orientações do mesmo, e assim implementá-lo e sustentá-lo na instituição partícipe deste estudo foram oferecidos cursos de formação com docentes e discentes Com o propósito de averiguar as formas de contribuição da implantação do PGR, aplicou-se questionários para os dois grupos de sujeitos participantes da pesquisa. Os referenciais teóricos que fundamentaram a pesquisa foram a discussão dos resultados que evidenciam que com a implementação do PGR o nível de conscientização dos discentes e docentes sobre o tratamento e o descarte dos resíduos foi ampliado, assim como o conhecimento quanto à responsabilidade civil em relação a gestão de resíduos. As atividades desenvolvidas nas aulas de Química Analítica Qualitativa foram adequadas aos princípios norteadores do PGR. De forma geral conclui-se que a existência de um PGR na escola favorece a formação de futuros profissionais cidadãos críticos, responsáveis e conscientes de seu papel na sociedade. Além disso, com a efetivação de um convênio entre a Secretaria Estadual de Educação (SEC) e o Centro de Gestão e Tratamento de Resíduos Químicos (CGTRQ) do Instituto de Química da Universidade Federal do Rio Grande do Sul (IQ/UFRGS) favorecerá a manutenção e o funcionamento do projeto. / In this dissertation, the general objective was the elaboration and implementation of a waste management project (PGR) that allowed to minimize and to guide adequate destination of waste generated during experimental activities of a public school in Porto Alegre that offers Technical Chemistry course (TQ). In order to do so, a qualitative investigation was carried out, such as a Case Study, where, following discussions with the school's management, as well as with the teachers of the course, the presence of environmental liabilities and habits adopted for the disposal of generated waste were verified in the experimental classes of some disciplines. The observations were recorded in a Field Diary. Afterwards, questionnaires were applied with teachers and students to diagnose their perceptions about the elaboration and implementation of a PGR. After identifying the needs and the school context, the PGR for the TQ was elaborated. In order for the whole school community to know the document and to adapt its practices to the orientations of the same, and to implement and sustain it in the participating institution of this study, training formation courses were offered with teachers and students. With the purpose of ascertaining the contribution forms of the PGR implementation, questionnaires were applied to the two groups of subjects participating in the research after PGR implementation The theoretical references that supported this dissertation were the discussion of the results that show that with the implementation of the PGR the level of awareness of the students and teachers about the treatment and disposal of the residues was amplified, as well as the knowledge about the civil responsibility in relation to Waste Management. The activities developed in Qualitative Analytical Chemistry classes were adequate to the guiding principles of the PGR. In general, it is concluded that the existence of a PGR in the school favors the formation of future professionals who are critical, responsible and aware of their role in society. In addition, with the implementation of an agreement between the State Department of Education (SEC) and the Center for Management and Treatment of Chemical Residues (CGTRQ) of Chemistry Institute at Federal University of Rio Grande do Sul (IQ/ UFRGS), it will promote to sustain PGR project.

Nesta dissertação, o objetivo geral foi a elaboração e implementação de um projeto de gestão de resíduos (PGR) que permitisse minimizar e orientar para a destinação adequada dos resíduos gerados nas atividades experimentais de uma escola da rede pública de Porto Alegre que oferece o curso Técnico em Química (TQ). Para tanto, foi realizada uma investigação qualitativa, do tipo Estudo de Caso, onde após tratativas com a direção da escola, assim como com os professores do curso, verificou-se a presença de passivo ambiental e os hábitos adotados para o descarte dos resíduos gerados nas aulas experimentais de algumas disciplinas. As observações foram registradas em Diário de Campo. Na sequência foram aplicados questionários com docentes e discentes, para o diagnóstico das suas percepções sobre a elaboração e implementação de um PGR. Após a identificação das necessidades e do contexto escolar, foi elaborado o PGR para o TQ. Para que toda a comunidade escolar conhecesse o documento e pudesse adaptar suas práticas às orientações do mesmo, e assim implementá-lo e sustentá-lo na instituição partícipe deste estudo foram oferecidos cursos de formação com docentes e discentes Com o propósito de averiguar as formas de contribuição da implantação do PGR, aplicou-se questionários para os dois grupos de sujeitos participantes da pesquisa. Os referenciais teóricos que fundamentaram a pesquisa foram a discussão dos resultados que evidenciam que com a implementação do PGR o nível de conscientização dos discentes e docentes sobre o tratamento e o descarte dos resíduos foi ampliado, assim como o conhecimento quanto à responsabilidade civil em relação a gestão de resíduos. As atividades desenvolvidas nas aulas de Química Analítica Qualitativa foram adequadas aos princípios norteadores do PGR. De forma geral conclui-se que a existência de um PGR na escola favorece a formação de futuros profissionais cidadãos críticos, responsáveis e conscientes de seu papel na sociedade. Além disso, com a efetivação de um convênio entre a Secretaria Estadual de Educação (SEC) e o Centro de Gestão e Tratamento de Resíduos Químicos (CGTRQ) do Instituto de Química da Universidade Federal do Rio Grande do Sul (IQ/UFRGS) favorecerá a manutenção e o funcionamento do projeto. / In this dissertation, the general objective was the elaboration and implementation of a waste management project (PGR) that allowed to minimize and to guide adequate destination of waste generated during experimental activities of a public school in Porto Alegre that offers Technical Chemistry course (TQ). In order to do so, a qualitative investigation was carried out, such as a Case Study, where, following discussions with the school's management, as well as with the teachers of the course, the presence of environmental liabilities and habits adopted for the disposal of generated waste were verified in the experimental classes of some disciplines. The observations were recorded in a Field Diary. Afterwards, questionnaires were applied with teachers and students to diagnose their perceptions about the elaboration and implementation of a PGR. After identifying the needs and the school context, the PGR for the TQ was elaborated. In order for the whole school community to know the document and to adapt its practices to the orientations of the same, and to implement and sustain it in the participating institution of this study, training formation courses were offered with teachers and students. With the purpose of ascertaining the contribution forms of the PGR implementation, questionnaires were applied to the two groups of subjects participating in the research after PGR implementation The theoretical references that supported this dissertation were the discussion of the results that show that with the implementation of the PGR the level of awareness of the students and teachers about the treatment and disposal of the residues was amplified, as well as the knowledge about the civil responsibility in relation to Waste Management. The activities developed in Qualitative Analytical Chemistry classes were adequate to the guiding principles of the PGR. In general, it is concluded that the existence of a PGR in the school favors the formation of future professionals who are critical, responsible and aware of their role in society. In addition, with the implementation of an agreement between the State Department of Education (SEC) and the Center for Management and Treatment of Chemical Residues (CGTRQ) of Chemistry Institute at Federal University of Rio Grande do Sul (IQ/ UFRGS), it will promote to sustain PGR project.

Nesta dissertação, o objetivo geral foi a elaboração e implementação de um projeto de gestão de resíduos (PGR) que permitisse minimizar e orientar para a destinação adequada dos resíduos gerados nas atividades experimentais de uma escola da rede pública de Porto Alegre que oferece o curso Técnico em Química (TQ). Para tanto, foi realizada uma investigação qualitativa, do tipo Estudo de Caso, onde após tratativas com a direção da escola, assim como com os professores do curso, verificou-se a presença de passivo ambiental e os hábitos adotados para o descarte dos resíduos gerados nas aulas experimentais de algumas disciplinas. As observações foram registradas em Diário de Campo. Na sequência foram aplicados questionários com docentes e discentes, para o diagnóstico das suas percepções sobre a elaboração e implementação de um PGR. Após a identificação das necessidades e do contexto escolar, foi elaborado o PGR para o TQ. Para que toda a comunidade escolar conhecesse o documento e pudesse adaptar suas práticas às orientações do mesmo, e assim implementá-lo e sustentá-lo na instituição partícipe deste estudo foram oferecidos cursos de formação com docentes e discentes Com o propósito de averiguar as formas de contribuição da implantação do PGR, aplicou-se questionários para os dois grupos de sujeitos participantes da pesquisa. Os referenciais teóricos que fundamentaram a pesquisa foram a discussão dos resultados que evidenciam que com a implementação do PGR o nível de conscientização dos discentes e docentes sobre o tratamento e o descarte dos resíduos foi ampliado, assim como o conhecimento quanto à responsabilidade civil em relação a gestão de resíduos. As atividades desenvolvidas nas aulas de Química Analítica Qualitativa foram adequadas aos princípios norteadores do PGR. De forma geral conclui-se que a existência de um PGR na escola favorece a formação de futuros profissionais cidadãos críticos, responsáveis e conscientes de seu papel na sociedade. Além disso, com a efetivação de um convênio entre a Secretaria Estadual de Educação (SEC) e o Centro de Gestão e Tratamento de Resíduos Químicos (CGTRQ) do Instituto de Química da Universidade Federal do Rio Grande do Sul (IQ/UFRGS) favorecerá a manutenção e o funcionamento do projeto. / In this dissertation, the general objective was the elaboration and implementation of a waste management project (PGR) that allowed to minimize and to guide adequate destination of waste generated during experimental activities of a public school in Porto Alegre that offers Technical Chemistry course (TQ). In order to do so, a qualitative investigation was carried out, such as a Case Study, where, following discussions with the school's management, as well as with the teachers of the course, the presence of environmental liabilities and habits adopted for the disposal of generated waste were verified in the experimental classes of some disciplines. The observations were recorded in a Field Diary. Afterwards, questionnaires were applied with teachers and students to diagnose their perceptions about the elaboration and implementation of a PGR. After identifying the needs and the school context, the PGR for the TQ was elaborated. In order for the whole school community to know the document and to adapt its practices to the orientations of the same, and to implement and sustain it in the participating institution of this study, training formation courses were offered with teachers and students. With the purpose of ascertaining the contribution forms of the PGR implementation, questionnaires were applied to the two groups of subjects participating in the research after PGR implementation The theoretical references that supported this dissertation were the discussion of the results that show that with the implementation of the PGR the level of awareness of the students and teachers about the treatment and disposal of the residues was amplified, as well as the knowledge about the civil responsibility in relation to Waste Management. The activities developed in Qualitative Analytical Chemistry classes were adequate to the guiding principles of the PGR. In general, it is concluded that the existence of a PGR in the school favors the formation of future professionals who are critical, responsible and aware of their role in society. In addition, with the implementation of an agreement between the State Department of Education (SEC) and the Center for Management and Treatment of Chemical Residues (CGTRQ) of Chemistry Institute at Federal University of Rio Grande do Sul (IQ/ UFRGS), it will promote to sustain PGR project.

Analog and digital structures can be written into thin surface layers of semiconductors by using focused ion beams of submicron dimensions. By inducing the phase transition from the crystalline (c) to the amorphous state (a) optical contrast is generated between areas of different exposure. The aim of this study was to investigate the properties of diamond as a high-density optical recording medium and to determine the corresponding irradiation parameters. To this end, single crystals of diamond were irradiated with self-ions of 75 key energy with fluences between F=0.3-l0xlO15 C/cm2 at about 100 K. The radiation damage, persisting after annealing treatments between 300-1700 K, was studied by Raman measurements, monitoring changes in the atomic bonding arrangements. Since the scattering cross-section of C sp2 bonds is 50x that of C sp3 bonds, this is an extremely sensitive technique in detecting changes in the initially purely sp3 state. The position and linewidth of the characteristic first-order phonon of crystalline diamond at 1332 cm-l reflect crystallinity and stress level, while bands between 1350-1700 cm-l indicate disorder. In utilizing the microscopic resolution of a Raman facility additional information was obtained on the spatial variation of the damage level. The optimum annealing temperature was found to be 1500 K. For F > 3xlO15C/cm2, the damage was irreversible, for F = 3xlO15C/cm2 the damage was only partly repaired after annealing at 1500 K and, for F < 3xlO15C/ cm2, the crystalline/amorphous contrast was reversible. For F < lxl015C/ cm2 Raman spectroscopy was not sensitive enough to detect the incurred damage. Infrared spectroscopy was used to classify the diamond samples according to type. / Dissertation (MSc (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted

Iron and manganese are relevant constituents of the earth's crust and both show increasing mobility when reduced by free electrons. This reduction is known to be controlled by microbial dissimilation processes. Alternative sources of free electrons in nature are cloud-to-ground lightning events with thermal and galvanic effects. Where thermal effects of lightning events are well described, less is known about the impact of galvanic lightning effects on metal mobilization. Here we show that a significant mobilization of manganese occurs due to galvanic effects of both positive and negative lightning, where iron seems to be unaffected with manganese being abundant in oxic forms in soils/sediments. A mean of 0.025 mmol manganese (negative lightning) or 0.08 mmol manganese (positive lightning) mobilization may occur. We suggest that lightning possibly influences biogeochemical cycles of redox sensitive elements in continental parts of the tropics/subtropics on a regional/local scale.