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Atributos do solo e da nutrição do cafeeiro em sistema agroflorestal e em monocultivo / Soil and nutritional status attributes of coffee under agroforestry systems and monocropJovan de Jesus 31 October 2008 (has links)
A produção de café é uma atividade importante para a economia do Brasil, maior produtor e também principal exportador. O cafeeiro apresenta ciclo bienal de produção, cuja oscilação é acentuada no Brasil dada às condições climáticas e ao sistema de cultivo predominante a pleno sol. Pesquisas envolvendo avaliação do estado nutricional do cafeeiro em sistemas agroflorestais são raras, o que dificulta as recomendações de adubação para esta condição. Objetivou-se neste estudo, o melhor entendimento da fertilidade do solo e do estado nutricional do cafeeiro em relação aos teores de N e K no microclima gerado pelo sistema agroflorestal e em monocultivo. A pesquisa foi conduzida no período de março de 2006 a maio de 2008, no campo experimental pertencente ao Departamento de Produção Vegetal da Escola Superior de Agricultura Luiz de Queiroz da Universidade de São Paulo (ESALQ/USP) em Piracicaba SP, localizada nas coordenadas geográficas 220 42 20 S, 470 37 22 W e altitude 565 m. O experimento foi composto de seringueiras do clone PB 235, plantada em dezembro de 1991, no espaçamento de 8,0 x 2,5 m e cafeeiros cv. Obatã IAC 1669-20, plantado em janeiro de 2002, no espaçamento de 3,4 x 0,9 m, sob diferentes condições de sombreamento: no sub-bosque e interfaceando as árvores da seringueira e em monocultivo. O delineamento experimental adotado foi o inteiramente casualizado com quatro repetições. O experimento de avaliação da fertilidade do solo constou de seis tratamentos, constituídos pelas radiações sobre o solo: 1) 6,4%; 2) 7%; 3) 35,4%; 4) 47,5%; 5) 60,9%; 6) 64,9%. O experimento de avaliação dos teores foliares de N e K do cafeeiro constou de quatro tratamentos, constituídos pelas radiações sobre os cafeeiros: 1) 35%; 2) 45%; 3) 90%; 4) 100%. O estudo constou, adicionalmente, dos experimentos de deposição e avaliação da velocidade de decomposição da serapilheira, frações da matéria orgânica, crescimento, peso foliar específico, anatomia foliar, maturação dos frutos e produção do cafeeiro e qualidade da bebida do café. As variáveis analisadas no experimento de fertilidade do solo foram; pH, P, K, Ca, Mg, soma de bases, H+Al, CTC, V % e matéria orgânica; a avaliação do estado nutricional constou das análises das variáveis N e K foliar. Os atributos de fertilidade do solo (pH e V %), foram mais elevados nos tratamentos 6,4%, 7% e 35,4%, especialmente nas camadas superficiais (0-2 e 2-7 cm) e o teor de matéria orgânica na camada de 0-2 cm, proporcionados pelas seringueiras. Menores teores de K do solo ocorreram nos tratamentos 7% e 35,4%, devido a absorção pelas seringueiras. A característica de CTC elevada do solo não foi modificada pelos tratamentos. Os teores foliares de N e K do cafeeiro a pleno sol alcançaram valores mais elevados e mais baixos, respectivamente, do que aqueles dos cafeeiros à sombra. Os cafeeiros sob 45% de irradiância mantiveram estado nutricional adequado em relação aos teores foliares de N e K. / Coffee production is an important activity in the economy of Brazil, first world producer and exporter. Coffee trees present biennial production cycles, with oscillation accentuated due to the climatic conditions and the production system in monocrop under full natural radiation. Studies involving the evaluation of nutritional status of coffee in agroforestry systems are scarce, what difficult the fertilization recommendations for this conditions. The objective of the this study was of getting a better understanding of the soil fertility and nutritional status, specially for the N and K content, of coffee trees under agroforestry system and monocrop. The research was conducted from March 2006 to May 2008, at the experimental field of the Plant Production Department of the Escola Superior de Agricultura Luiz de Queiroz of the Universidade de São Paulo (ESALQ/USP), in Piracicaba SP (220 42 20 S, 470 37 22 W) at the altitude of 565 m. The experiment was composed of rubber trees, clone PB 235, planted in December 1991, in the spacing of 8.0 x 2.5 m and coffee trees cv. Obatã IAC 1669-20, planted in January 2002, in the spacing of 3.4 x 0.9 m, under different shading conditions: undertorey or interfacing the rubber trees and in monocrop. The experimental design was completely randomized with four replications. The soil fertility experiment had six treatments, done by the different radiation regimes reaching the soil surface: 1) 6.4%; 2) 7%; 3) 35.4%; 4) 47.5%; 5) 60.9%; 6) 64.9%. The coffee nutritional status, in terms of the N and K leaf content had four treatments, done by the different radiation regime reaching the coffee canopy: 1) 35%; 2) 45%; 3) 90%; 4) 100%. Additionally, the study involved the evaluation of the litter deposition and decomposition rates, the soil organic matter fractions, coffee trees growth, its specific leaf area and anatomy, beans maturation, coffee yield and beverage quality. The variable under analysis in the soil fertility experiment were; pH, P, K, Ca, Mg, bases sum, H+Al, CTC, V % and organic matter; in the nutritional status were the N and K leaf content. The soil fertility attributes of pH and V % were improved in the treatments 6.4%, 7% e 35.4%, specially in the upper soils layers (0-2 e 2-7 cm) and organic matter content in the top soil layer (0-2 cm), due to the effect of the rubber trees. Lower K contents in the soil occurred in the treatments 7% e 35.4%, due to the rubber root uptake. The natural high CTC of the soil was not modified by treatments. N and K leaf content of coffee trees under full natural radiation (monocrop) reached the highest and lowest levels, respectively, in comparison with coffee trees under shade. Coffee at 45% of natural radiation maintained appropriate nutritional status in terms of N and K leaf content.
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Santos das avenidas: a moradia burguesa no início do século XX / Santos, the city of avenues: the bourgeoisie dwelling in the beginning of the century XXCynthia Regina de Araujo Evangelista dos Santos 08 August 2007 (has links)
Estudo da arquitetura das moradias da burguesia santista no período do auge da exportação do café - passagem do século XIX para o XX - até 1929. São analisadas em especial as residências localizadas nas avenidas Ana Costa e Conselheiro Nébias, novos eixos que partiram do núcleo colonial antigo e seguiram em direção às praias organizando a ocupação das novas áreas da cidade. Reconhecimento desse período como o momento em que a cidade passou por profundas transformações - econômicas, sociais e culturais - recebeu as ferrovias, foi urbanizada e saneada com sistema de canais e viu seu porto se transformar no maior exportador de café do país. / Architectural study of santistas bourgeoisie dwelling during the coffee exportation peak in the end of the century XIX and beginning of the XX until 1929. A special focus is given to the houses located at avenida Ana Costa and avenida Conselheiro Nébias, the new areas that originated from the old colonial center and continued developing towards the beach direction resulting in the organization of new living areas in the city. Acknowledgment of this period as the moment through which the city went through deep changes economic, social and cultural as well as when railways were constructed, urbanization and sanitation with drainage channels took place, and when its port became the biggest coffee exporter.
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Uma sociedade em formação: terra, população e escravidão na Mata mineira – Mar de Espanha, primeira metade do século XIXSouza, Thiago Firmino de 09 September 2016 (has links)
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Previous issue date: 2016-09-09 / Essa pesquisa tem como tema a formação da cafeicultura em Minas Gerais. Utilizamos principalmente a Lista Nominativa de Habitantes de 1831, os inventários post-mortem e o Registro Paroquial de Terras relativos a Mar de Espanha. Por meio desta documentação, pudemos realizar uma análise sócio-demográfica da população mardespanhense, bem como investigar a propriedade escrava e a propriedade agrária na localidade. Nos concentramos na primeira metade do século XIX, período de montagem da cafeicultura na Zona da Mata mineira, antes da consolidação do sistema agroexportador na região. / This research’s theme is the formation of coffee growing in Minas Gerais. We primarily use
the List of Inhabitants of 1831, post-mortem inventories and the Parish Register of Lands of
Mar de Espanha. Through this documentation, we conduct a socio-demographic analysis of
Mar de Espanha’s population and investigate the slaveholdings and land ownership in the
area. We focus on the first half of the nineteenth century, known as the coffee production
assembly period in Minas Gerais’ Zona da Mata, before the consolidation of the coffee agroexport
system in the area.
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Estruturas de governança e a capacidade de inovação em pequenas empresas: caso da indústria brasileira de torrefação e moagem de café / Governance structures and innovative capabilities in small firms: case of the Brazilian roast & ground coffee industryGabriela Feresin Jardim 14 June 2012 (has links)
O que motivou a realização desse trabalho foi a pouca relevância que os estudos econômicos, em geral, atribuem à capacidade das firmas de pequeno e médio porte de inovarem. Essas firmas representam a maior parte das empresas brasileiras e respondem por mais de dois terços das ocupações do setor privado (SEBRAE, 2012). Dessa forma, entender essa questão é de fundamental importância, pois a inovação pode incrementar a competitividade dessas empresas diante da concorrência no mercado nacional e internacional. Abordagens recentes da Economia das Organizações relacionam as inovações às estruturas organizacionais das firmas (BARBIERI; ÁLVARES, 2004; COOMBS; METCALFE, 2005; GRANDORI; FURNARI, 2008, 2010). Assim, o objetivo desta pesquisa é investigar as combinações de estruturas de governança (interna e externa) que permitem maiores possibilidades de desenvolvimento das capacidades de inovação das pequenas firmas. Indo além da abordagem de Grandori e Furnari (2008, 2010), os quais mostram que existe uma relação entre as estruturas de governança interna e a capacidade de inovação das firmas, esta dissertação também incorpora o âmbito externo, na medida em que se admite que o processo de inovação envolva também interações entre as estruturas de governança externa à firma. Essas questões foram abordadas a partir da literatura da Nova Economia Institucional e testadas por meio de uma survey com 110 indústrias brasileiras de torrefação e moagem de café. Dois tipos de inovação foram investigados: i. produto; ii. método/processo. Para encontrar as combinações de elementos foi utilizada a Análise Comparativa Qualitativa (QCA) no software fs/QCA versão 2.0 (RAGIN, 2008). Tem-se como hipótese que a capacidade de inovar está mais presente em firmas que adotam um mix de estruturas de governança (interna e externa) do que as que apresentam estruturas singulares. Como resultado verificou-se que as estruturas de governança interna plurais, que combinam incentivos monetários, burocráticos e comunitários, apresentaram resultados mais consistentes para a inovação das pequenas firmas de torrefação. No que se refere às estruturas de governança externa, a principal estrutura apresentada foi a de mercado tanto do lado dos fornecedores quanto dos clientes. Essa estrutura singular não apresentou resultados significativos para as capacidades de inovação, corroborando com a hipótese apresentada. Observou-se ainda que a combinação entre as estruturas de governança interna e externa não é complementar, visto que para as firmas de torrefação inovadoras as estruturas de governança interna foram as que mais tiveram impacto. Esses resultados, ao permitirem identificar os requisitos organizacionais que produzem maiores possibilidades de inovação, podem ajudar a traçar ações de políticas públicas e privadas para as empresas brasileiras de modo a melhorar a sua taxa de inovação e a competitividade em seus mercados. / The motivation for this work is the lack of relevance generally ascribed by economic studies to the innovative ability of small and mid-sized firms. These firms represent the majority of Brazilian companies, accounting for over two thirds of employment in the private sector (SEBRAE, 2006). Understanding of this issue is important, because innovation can enhance their competitiveness in the global and domestic market. Also, recent approaches from the Economics of Organizations associate innovations with the organizational structures of firms (BARBIERI; ÁLVARES, 2004; COOMBS, METCALFE, 2005; GRANDORI, FURNARI, 2008, 2010). This work therefore aims to find the combinations of governance structures (internal and external) that allow the greatest scope for developing the innovation capacity of small firms. Going beyond Grandori and Furnari\'s approach (2008, 2010), which demonstrates that a relationship exists between internal governance structures and a firm\'s innovation capacity, this paper also incorporates the external framework insofar as it accepts that the innovation process also involves interactions between governance structures external to the firm. We draw on the literature of the New Institutional Economics to address these issues and test them through a survey of 110 Brazilian R&G coffee industries. Two types of innovation are investigated: i. product; ii. method/process. To determine the combinations of elements we used the Qualitative Comparative Analysis (QCA) software fs/QCA, version 2.0 (RAGIN, 2008). Our hypothesis is that the ability to innovate is more prevalent in firms that use a mix of governance structures (internal and external) than in those with a singular structure. As a result, it was found that plural internal governance structures, which combine monetary, bureaucratic, and community incentives, have more consistent innovation results for small roasting firms. With regards to external governance structures, the main structure presented--concerning both customers and suppliers--was the market. This unique structure did not show significant results for innovation capacity, supporting the present hypothesis. It was also observed that the combination of internal and external governance structures is not complementary, because for the innovative R&G firms the internal governance structures saw the greatest impact. In allowing the identification of the organizational requirements that create greater opportunities for innovation, these results can help chart the actions of public and private policies which enable Brazilian companies to improve their rate of innovation and competitiveness in their markets.
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Manejo integrado de pragas na cultura do morangueiro no sul de Minas Gerais / Integrade pest management in culture of strawberry in southern of Minas GeraisFernanda de Cássia Neves Esteca 17 January 2017 (has links)
O sul de Minas Gerais é a principal região produtora de morangos (Fragaria x ananassa Duch.) no Brasil. O ácaro-rajado, Tetranychus urticae Koch (Acari: Tetranychidae), é considerado uma das principais pragas do morangueiro no Brasil e em vários países. Uma prática importante na cultura do morango refere-se à cobertura de solo, usualmente realizada com filme de polietileno, porém além de ser caro gera resíduos muito persistentes no ambiente. Objetivou-se com este trabalho comparar a resistência de oito genótipos de morango (\'Albion\', \'IAC Guarani\', \'IAC Princesa Isabel\', \'Oso Grande\', IAC T-0104, IAC 12, IAC 4 e IAC 1.13) ao ácaro-rajado; determinar o efeito da cobertura de solo (com a polpa de café desidratada, conhecida como palha de café) nas pragas/ patógenos e ácaros predadores desta cultura; comparar a ocorrência de pragas, patógenos e inimigos naturais entre um cultivo orgânico e outro convencional de morango. Os resultados obtidos indicaram que \'IAC Princesa Isabel\', IAC T-0104 e IAC 12 são resistentes, IAC 1.13 e IAC 4 apresentam resistência moderada e \'IAC Guarani\', \'Oso Grande\' e \'Albion\' são suscetíveis ao ácaro-rajado. \'Oso Grande\' e \'Albion\' são bastante utilizadas pelos produtores do sul de Minas Gerais. O uso de palha de café aumentou o número de predadores edáficos, tanto no solo dos canteiros (campo) e em vasos (laboratório) como em folíolos de morangueiro. O Gamasina Proctolaelaps pygmaeus (Müller) (Melicharidae) foi visto sobre morangueiros, principalmente no período noturno. Maior número de ácaro-rajado e maior severidade de doenças foram observados em plantas cultivadas em solo coberto com polietileno. Além disso, foi maior o nível de infecção de ácaro-rajado pelo fungo Neozygites floridana (Weiser e Muma) em plantas cultivadas em solo coberto com palha de café. Não foi observada diferença significativa entre a produtividade da cultura em solo coberto com polietileno e em solo coberto com palha seca de café. Os resultados da comparação da ocorrência de ártropodes e patógenos entre sistema orgânico e convencional mostraram menor ocorrência de ácaro-rajado e predadores em cultivo de morangueiro convencional, porém ocorrência considerável de tripes, mosca-branca e mofo cinzento. A incidência de dendrofoma e mancha de pestalotia foi a mesma nos dois sistemas de cultivos. Os resultados sugerem a conveniência de se continuar o processo de desenvolvimento dos genótipos que se mostraram menos afetados pelo ácaro-rajado, para que estes possam no futuro ser utilizados pelos produtores, e a condução de estudos complementares, que avaliem o desempenho de cultivos em sistema orgânico que incorporem o uso da palha de café para a cobertura do solo. / The southern of Minas Gerais is the main region producing strawberries (Fragaria x ananassa Duch.) in Brazil. The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is considered one of the main strawberry pests in Brazil and in several countries. An important practice in strawberry cultivation refers to soil cover, which is usually made with polyethylene film, but it is expensive and generates very persistent residues in the environment. The objective of this study was to compare the resistance of eight strawberry genotypes (\'Albion\', \'IAC Guarani\', \'IAC Princesa Isabel\', \'Oso Grande\', IAC T-0104, IAC 12, IAC 4 and IAC 1.13); to determine the effect of soil cover (with dehydrated coffee pulp, known as coffee straw) on the pests mites/ pathogens and predatory mites of this crop; to compare the occurrence of pests, pathogens and natural enemies between an organic and a conventional strawberry crop. The results indicated that \'IAC Princesa Isabel\', IAC T-0104 and IAC 12 are resistant, IAC 4 and IAC 1.13 are moderately resistant, and \'IAC Guarani\', \'Oso Grande\' and \'Albion\' are susceptible to the two-spotted spider mite. \'Oso Grande\' and \'Albion\' are widely used by producers in the southern of Minas Gerais. The use of coffee straw increased the number of edaphic predators, both in the soil beds (field) and in pots (laboratory) as well as in strawberry leaflets. The Gamasina Proctolaelaps pygmaeus (Müller) (Melicharidae) was seen on strawberry leaftlets, mainly in the nocturnal period. Higher numbers of the two-spotted spider mites and disease severity were observed in plants grown on soil covered with polyethylene. In addition, the level of the two-spotted spider mite infected by the fungi Neozygites floridana (Weiser and Muma) was higher in plants cultivated in soil covered with coffee straw. No significant difference was observed between yield in soil covered with polyethylene and in soil covered with dry coffee straw. The results of the comparison of the occurrence of arthropods and pathogens between the organic and conventional systems showed fewer occurrences of the two-spotted spider mites and predators in conventional strawberry cultivation, but considerable occurrence of thrips, whitefly and gray mold. The incidence of dendrophoma and leaf spots caused by pestalotia was the same in both cropping systems. The results suggest the convenience to continue the development process of the genotypes that were less affected by the two-spotted spider mite, which could be used in the future by producers, and the conduction of complementary studies to evaluate the performance of crops in organic system that incorporate the use of coffee straw as soil coverage.
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AS ALETRNATIVAS DA AGRICULTURA FAMILIAR COMO ESTRATÉGIA DE MANUTENÇÃO E PERMANÊNCIA NO ESPAÇO RURAL DO MUNICÍPIO DE TABAPUÃ, SP NAS SUCESSIVAS EXPANSÕES DE MONOCULTURAS DE CAFÉ, LARANJA E CANA-DE-AÇÚCAR / ALTERNATIVES OF AGRICULTURE FAMILY AS A STRATEGY OF MAINTENANCE AND PERMANENCE IN THE RURAL SPACE IN MUNICIPALITY OF TABAPUÃ, SP IN SUCCESSIVE EXPANSION OF COFFEE, ORANGE AND CANE SUGAR MONOCULTURESPelisson, Guilherme Valagna 04 March 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper aims to recognize the strategies of family farmers face to expansion of monoculture coffee, orange and sugarcane in rural areas of the municipality of Tabapuã, Sao Paulo. For this we carried out a research on different methodological steps: first, there was the literature; in another, collected secondary data (IBGE, Fundação Seade, Casa da Agricultura, Sindicato dos Trabalhadores Rurais e Biblioteca Municipal); and finally, there was the field work, striving to carry out structured interviews with research subjects. Please note that the intense production of farmers triggered processes of organization / reorganization of socio-territorial unit, resulting in this space, the dismantling and reduction of family farming. The expansion of monoculture plantations for export resulted in effects in the field of this municipality. Regarding the coffee monoculture, it emphasizes the sharecropping. At another point was the hiring of temporary workers (bóias-frias) for the harvest of orange, resulting socioeconomic impacts. Finally, the replacement key cultures occurred and even the area for coffee and orange due to expansion from cane sugar. With respect to impacts occurring to family farming, points up the difficulty of maintaining this activity against the obstacles imposed by the expansion of cash crops of interest in the international market. Therefore, there was the impact from expansion of monocultures in the analyzed period, as well as family farming, which is unassisted by the municipal government. Moreover, there was a lack of guidance these farmers across the work of the state to the development of this activity, which, in turn, is characterized as fundamental supplying basic and essential food for the Brazilian population. / Neste trabalho almeja-se reconhecer as estratégias dos agricultores familiares frente a expansão das monoculturas de café, de laranja e de cana-de-açúcar no espaço rural do município de Tabapuã, São Paulo. Para isso realizou-se uma investigação em diferentes etapas metodológicas: inicialmente, fez-se a pesquisa bibliográfica; em outra, coletou-se dados secundários (IBGE, Fundação Seade, Casa da Agricultura, Sindicato dos Trabalhadores Rurais e Biblioteca Municipal); e por fim, fez-se o trabalho de campo, primando a realização de entrevistas estruturadas junto aos sujeitos da pesquisa. Salienta-se que a intensa produção dos agricultores desencadeou processos de organização/reorganização socioespacial desta unidade territorial, ocasionando, nesse espaço, a desarticulação e redução da agricultura familiar. A expansão da plantação de monocultivos para a exportação resultou em efeitos no campo deste município. No que tange a monocultura do café, ressalta-se a meação. Em outro momento houve a contratação de trabalhadores temporários (boias-frias) para a colheita da laranja, resultando impactos socioeconômicos. Por fim, ocorreu a substituição de fundamentais culturas e, até mesmo, da área destinada ao café e a laranja, devido a expansão da cana de açúcar. No que tange aos impactos ocorridos à agricultura familiar, aponta-se a dificuldade de manutenção dessa atividade frente aos obstáculos impostos pela expansão das culturas comerciais de interesse no mercado internacional. Portanto, verificou-se os impactos relacionados a expansão das monoculturas no período analisado, bem como, à agricultura familiar, a qual encontra-se desassistida pelo poder público municipal. Além disso, constatou-se a falta de orientação desses agricultores frente a atuação do Estado para o desenvolvimento desta atividade, a qual, por sua vez, caracteriza-se como fundamental abastecedora de alimentos básicos e essenciais para a população brasileira.
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Využití sociálních sítí pro podporu webového portálu / Use of social networks to support the web portalMysliveček, David January 2017 (has links)
This diploma thesis deals with the use of social networks for business support. Its main focus lies in designing a strategy for working with Facebook's social network of Coffee Media s.r.o. The first part of this work summarizes general theoretical knowledge from the field of social networks and competitive intelligence. The individual concepts are explained and the area that the thesis deals with is determined. The second part of this work consists of the proposal of the web solution of Coffee Media. The first is the comparison of individual web site creation options, the key factors and creative requirements are determined, according to which the most suitable solution is then selected. With this solution, websites are subsequently designed and implemented. The third part deals with a detailed analysis of competition in the field of online marketing. Four competing companies are selected and their work with the Facebook social network is analysed. The analysis is carried out using both a customized method and a free specialized tool. Based on this analysis, individual trends in Facebook social networking are determined. The last part proposes detailed strategy for working with the Facebook social network. In this strategy, a publishing plan for contributions is designed and individual advertising campaigns are designed to promote Coffee Media.
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Versatile silicone rubber samplers for trace organic analysis in a chromatography-mass spectrometry laboratoryNaude, Yvette 05 April 2013 (has links)
Extraction is required to separate and concentrate trace level analytes from the sample matrix prior to gas chromatography (GC). Classical extraction procedures utilise large amounts of hazardous solvents, generate waste, and sensitivity limitations are associated with the injection of microlitre amounts of the final solvent extract. In response to real world challenges, and to overcome the problems associated with solvent extraction, novel silicone rubber (polydimethylsiloxane (PDMS)) samplers were developed for solvent free enrichment of trace level analytes from indoor air, contaminated soil, desert soil, ultra high temperature (UHT) milk and Pinotage wine. Versatile PDMS samplers as a loop, a multichannel trap, or a denuder for trace environmental forensics, geochemical and aroma investigations are presented. A unique off-line multidimensional GC approach involving heart-cut gas chromatographic fraction collection is described, as is off-line olfactory assessment of recombined heart-cuts for synergistic odour effects. PDMS loop samplers were used for the extraction of DDT (1,1,1- trichloro-2,2-bis(p-chlorophenyl)ethane) and its associated environmental pollutants from soil samples. Miniature denuder samplers accomplished separate concentration of vapour phase and of particulate phase fractions of DDT and its associated environmental pollutants from indoor air, in a single step. Ratios of airborne p,p’-DDD/p,p’-DDT and of o,p’-DDT/p,p’-DDT are unusual and do not match the ideal certified ingredient composition required of commercial DDT. Results suggest that commercial DDT used for indoor residual spraying may have been compromised with regards to insecticidal efficacy, demonstrating the power of this new environmental forensics tool. Multichannel PDMS trap samplers were used in a unique heart-cut multidimensional GC approach for off-line enantiomeric separation of o,p’-DDT and o,p’-DDD in air and soil. This alternative multidimensional method is compared to the complementary technique of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry detection (GCxGC-TOFMS). PDMS loop samplers were also employed for the solvent free extraction of hydrocarbons from desert soil to investigate, for the first time, a possible geochemical origin of the enigmatic fairy circles of Namibia. It is proposed that microseepages of natural gas and low volatility hydrocarbons are expressed at the surface as a geobotanical anomaly of barren circles and circles of altered vegetation. Multichannel PDMS trap samplers were utilised for sampling of the headspace of UHT milk and of Pinotage wine, and to study off-line, using a portable olfactometer, synergistic effects between recombined heart-cut aroma compounds. Olfactory results show that a synergistic combination of 2- heptanone and 2-nonanone was responsible for a pungent cheese-like odour in UHT milk, while a synergistic combination of furfural and 2-furanmethanol was responsible for a roast coffee bean-like odour in coffee style Pinotage wine. The small, low cost samplers are quick and easy to assemble and they fit commercial thermal desorber systems. The PDMS samplers are reusable. Solvent extraction of the sampling materials, extract clean-up and pre-concentration are not required. Thus, potential loss of analyte, introduction of contaminants and waste disposal are minimised. Solvent free thermal desorption permits transfer of the entire sample mass to the cooled injection system (CIS) inlet of a GC resulting in greater sensitivity when compared to injection of microlitre amounts of a solvent extract. This allowed for sampling of smaller sized soil samples, shorter air sampling times and lower air sampling flow rates when compared to solvent based methods. / Thesis (PhD)--University of Pretoria, 2013. / Chemistry / unrestricted
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A Market Study of Organic and Fair Trade Coffee in BoliviaEstevez, Christopher L 09 June 2015 (has links)
The purpose of this research is to study the commercialization of Fairtrade and Organic coffee in the Bolivia. Fairtrade and Organic coffee are alternative trade systems designed to promote the equitable and environmentally sustainable production of coffee. However, these alternative trading systems often fail to meet these goals. The producers and environment these systems are intended to protect remain marginalized. These failures are due to a number of local institutions. In order to better understand these institutions, this research conducted interviews of various stakeholders including producers, cooperative leaders, organic/Fair Trade certifiers, government agencies and private buyers. All these stakeholders influence the success of the alternative trade systems. By better understanding how these stakeholders impact the commercialization of coffee in Bolivia; new policies can be develop to improve the outcomes of alternative trade, to benefit both producers and the environment. This is especially critical in Bolivia because of the environmentally sensitive area in which coffee is grown, the potentially damaging impact of coca on the region and, the devastating economic impact to farmers.
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Estudio de prefactibilidad para la instalación de una planta de elaboración de carbón activado a base de cáscara de caféCarrillo-Zamora, Jose-Manuel, Lembcke-Berninzon, Adriana January 2015 (has links)
El presente trabajo tiene como objetivo satisfacer una demanda generada en el mercado del negocio más grande del país: la minería. El presente proyecto generará bienestar económico para una parte de la población ya que generará trabajo y desarrollo económico. El documento presenta todo el sustento social, económico, operativo y tecnológico del proyecto. El producto generado es un producto poco común en el mercado pero tiene aplicaciones muy beneficiosas para el procesamiento de diferentes minerales. La propuesta plantea el diseño de una planta de producción de carbón activo en base a cáscara de café. El procesamiento de minerales con el producto presentado agrega valor al producto mineral final, generando una ventaja competitiva en el mercado minero, por lo que consideramos que el producto tendrá una gran acogida y podría motivar a muchos negocios mineros a darle diferentes ventajas competitivas a diferentes minerales. / The present work has the purpose of satisfying a demand generated in the biggest business on the country: mining. The present project will generate economic wellness for a part of the population because it will generate work and economic development. This document presents the economic, social, operative and technological support for the project. The product generated is poorly known on the market but has beneficial applications on minerals processing. The project proposal presents the design of an coffee shell based activated carbon production plant. The minerals processing with the presented product adds value on the final mineral product, generating a competitive advantage in the mining market, that is why we consider that the product will have a big reception and could motivate different mining businesses to add different competitive advantages to their minerals. / Trabajo de investigación
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