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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

UM ESPECTROMETRO \"MINI-ORANGE\" PARA ELECTRONS / A mini-orange spectrometer for electrons

Nelson Canzian da Silva 04 May 1990 (has links)
Foi projetado e construído um espectrômetro Mini-Orange (MO) para eléctrons, utilizando imãs planos permanentes e um detector de barreira de superfície. Foram determinadas as funções de transmissão de diferentes configurações do sistema, para energias entre 200-1100 keV. Foi desenvolvido um modelo matemático do sistema, a partir de solução analítica para o campo de um imã plano e da integração numérica da equação de movimento dos eléctrons no campo de MO. As funções de transmissão assim obtidas foram comparadas aos resultados experimentais e mostraram um bom acordo para energias baixas e intermediárias. / A Mini-Orange spectrometer for electrons was designed and built, using plane permanent magnets and a surface barrier detector. Transmission functions were obtained for various system configurations and for energies between 200-1100 keV. A mathematical model of the system was developed, using the analytical solution for the field of a plane magnet and the numerical integration of the equation of motion of the electrons in the MO magnetic field. The calculated transmission functions were compared to the experimental data, showing a good agreement for low and intermediate energies.
72

Reação de variedades de cana-de-açúcar à ferrugem alaranjada (Puccinia kuehnii) / Reaction of sugarcane varieties to orange rust (Puccinia kuehnii)

Roberto Giacomini Chapola 04 December 2013 (has links)
A ferrugem alaranjada da cana-de-açúcar, causada pelo fungo Puccinia kuehnii, é atualmente a doença que mais preocupa o setor sucroenergético brasileiro, devido a sua introdução recente no país e aos prejuízos causados em indústrias canavieiras ao redor do mundo. A doença é controlada com variedades resistentes e por isso há a necessidade de maiores informações sobre a reação das cultivares mais importantes no Brasil. Os objetivos deste trabalho foram: (i) avaliar a reação de variedades de cana-de-açúcar à ferrugem alaranjada, em condições de infecção natural no campo; (ii) determinar a melhor época para avaliação da doença; (iii) estabelecer um método, em casa de vegetação e com inoculação artificial do patógeno, para seleção rápida de variedades com resistência no campo. Dezessete variedades foram avaliadas quanto às suas reações a P. kuehnii em dois experimentos de campo, plantados em abril e julho de 2011; neste último, após a colheita em maio de 2012, a cana-soca também foi avaliada. Para multiplicar e uniformizar a distribuição do inóculo, a variedade suscetível SP89-1115 foi usada como bordadura e plantada entre os blocos e em duas linhas, dividindo cada experimento ao meio. Avaliou-se a severidade da doença a cada 15 dias e, a partir destes dados, calculou-se a área abaixo da curva de progresso da doença (AACPD) e obteve-se a severidade máxima da doença. Para identificar o melhor período de avaliação, realizou-se análise de correlação entre a AACPD e cada levantamento de severidade. Em casa de vegetação, seis variedades com reações distintas à doença, com base nos resultados obtidos no campo, foram inoculadas com uma suspensão de 104 urediniósporos viáveis mL-1 de P. kuehnii, com auxílio de pulverizador manual, 60 dias após o plantio. As plantas foram mantidas por 24 horas em câmara de orvalho e, posteriormente, transferidas para casa de vegetação. Foram determinados os períodos de incubação e latência, o número de pústulas por cm2 e a severidade da doença. Oito das 17 variedades avaliadas no campo mostraram alta resistência à doença. As cultivares RB72454 e SP89-1115 foram as mais suscetíveis, seguidas da SP79-2233; por isso, o cultivo das mesmas não é recomendado. As variedades RB925211, SP81-3250, RB855156 e RB92579 tiveram reação intermediária, sendo que as duas primeiras apresentaram maiores níveis da doença. Avaliações realizadas no mês de março foram as que mais se correlacionaram com a AACPD, portanto este é o melhor período para determinar a reação de variedades de cana-de-açúcar à ferrugem alaranjada. O comportamento das variedades em casa de vegetação foi semelhante ao observado no campo, especialmente em relação às cultivares suscetíveis e resistentes. Assim, o método aplicado em casa de vegetação mostrou potencial para selecionar, em poucos dias, cultivares com resistência à doença no campo, além de economizar espaço, mão de obra e de ser facilmente executado. / Currently, sugarcane orange rust, caused by Puccinia kuehnii, is the disease that most concerns the Brazilian sugarcane industry, due to its recent introduction in the country and the damage caused to sugarcane industries all over the world. The disease is controlled with resistant varieties; hence there is a need for more information about the reaction of the major cultivars in Brazil. The objectives of this work were: (i) to evaluate the reaction of sugarcane varieties to orange rust in field, under natural infection conditions; (ii) to determine the best time for disease assessment; (iii) to establish a method in greenhouse, based on artificial inoculation, for rapid selection of field resistant varieties. Seventeen varieties were studied in two field experiments, planted in April and July 2011; in the latter, after the harvest in May 2012, the ratoon was also evaluated. The susceptible variety SP89-1115 was used as border and planted between the blocks in two lines, dividing each experiment in two halves in order to multiply and standardize the inoculum in the area. Disease severity was evaluated every 15 days and the area under disease progress curve (AUDPC) was calculated and the maximum disease severity was obtained. To identify the best time for disease assessment, a correlation analysis between the AUDPC and each disease severity assessment was done. In greenhouse, six varieties with different reactions to the disease based on results obtained in field were inoculated with a suspension of 104 viable urediniospores mL-1 of P. kuehnii with a manual sprayer 60 days after planting. Plants were maintained in dew chamber for 24 hours and afterwards they were transferred to the greenhouse. The incubation and latent period were determined as well as the number of pustules cm-2 and disease severity. Eight out of 17 varieties evaluated in field showed high disease resistance. The varieties RB72454 and SP89-1115 were the most susceptible, followed by SP79-2233; therefore, their commercial cultivation is not recommended. The varieties RB925211, SP81-3250, RB855156 and RB92579 had intermediate reaction, with the first two showing higher disease levels. Evaluations performed in March showed the highest correlation with AUDPC, thus this period is the best for determining sugarcane reaction to orange rust. The varieties reaction in greenhouse was similar to that observed in the field, particularly in relation to susceptible and resistant cultivars. So, the method applied in greenhouse showed potential to select, in a few days, field disease-resistant varieties, besides saving space and labor and being easily implemented.
73

Viabilidade técnica e econômica do aproveitamento para consumo humano da água evaporada na industrialização de suco de laranja concentrado / Technical and economic viability of use for human consumption of the evaporated water in the concentrated orange juice industrialization

Coelho, Alba Lucia Andrade, 1960- 06 July 2013 (has links)
Orientador: José Euclides Stipp Paterniani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-23T03:05:09Z (GMT). No. of bitstreams: 1 Coelho_AlbaLuciaAndrade_D.pdf: 2283159 bytes, checksum: 71a31d2665332e37c20d41058c042f35 (MD5) Previous issue date: 2013 / Resumo: Além do suco de laranja concentrado congelado, as indústrias do setor produzem vários subprodutos. A água evaporada é produzida na etapa de concentração do suco, sendo separada por condensação no próprio evaporador. Essa água evaporada é totalmente aproveitada pelas próprias indústrias em várias operações, porém de forma pouco nobre. Considerando que se trata de produto oriundo da própria fruta, o presente trabalho teve como proposta o seu aproveitamento para comercialização na forma de "água da fruta" envasada para consumo humano, avaliando ainda a viabilidade econômica dessa forma de aproveitamento. Também foi proposta uma tecnologia para tratamento dos efluentes líquidos das indústrias cítricas, permitindo sua recirculação. Para avaliar a viabilidade técnica e econômica do aproveitamento para consumo humano, de parte da água evaporada durante a produção de sucos cítricos concentrados, foram realizadas as etapas de caracterização da água evaporada de suco de laranja, identificando os parâmetros que necessitavam correção (cor e turbidez), adotando padrão brasileiro para água envasada para consumo humano como referência. Em seguida, foi identificada tecnologia para adequar os parâmetros de qualidade da água evaporada, para alcançar padrões para consumo humano, envolvendo filtração em carvão ativado, ultrafiltração (membrana Celulose 30 KDa) e desinfecção por ultravioleta. O produto obtido foi então caracterizado por análises de substâncias inorgânicas e orgânicas, agrotóxicos, propriedades físicas e perfil de voláteis, se enquadrando no padrão brasileiro para águas minerais e mineralizadas, comprovando assim, a viabilidade técnica do aproveitamento para consumo humano. Quanto à análise sensorial, a aceitação foi de cerca de 50%, quando a água de laranja foi produzida a partir de água evaporada de suco de laranja concentrado em final de safra. Por outro lado, foram observadas tendências de aceitação superior a 90% quando o produto foi processado a partir de fruta de pico de safra. Para avaliar a viabilidade econômica, foi elaborado anteprojeto de instalação industrial hipotética para produção de 1.000 litros/hora de água de laranja envasada. O ponto de equilíbrio obtido com a estrutura de custos e receitas recomendou uma utilização da capacidade produtiva superior a 57,04% e revelou possibilidade de sucesso devido à significativa taxa interna de retorno de 28,30% ao ano e um tempo de recuperação do capital ao redor de 3,5 anos. Quanto ao tratamento de efluentes da indústria cítrica visando reuso potável, a estimativa realizada apontou que os recursos gerados pela unidade industrial de produção de água de laranja não são suficientes para implantar e operar uma estação de tratamento de efluentes no cenário atual, se membrana MBR for utilizada, podendo contribuir apenas parcialmente para tal implantação / Abstract: Besides the frozen concentrated orange juice, industry sector produce several byproducts. The evaporated water is produced in the juice concentration step, being separated by condensation in the evaporator itself. This evaporated water is fully exploited by the industries themselves in various operations, but so little noble. Whereas it is a product from the fruit itself, the present study proposed its use for marketing in the form of "fruit water" bottled for human consumption, still assessing the economic viability of this form of exploitation. It was also proposed a wastewater treatment for citrus industries, allowing their reuse and its costs estimated. To evaluate the technical and economic viability of utilization for human consumption of the water evaporated during the production of citrus juice concentrates, the following steps took place: characterization of evaporated water orange juice, identifying parameters that needed correction (color and turbidity), adopting the Brazilian standards for bottled water for human consumption as a reference. Then, a technology was identified to match the quality parameters of the evaporated water, to achieve standards for human consumption, involving activated carbon filtration, ultra filtration (30 kDa cellulose membranes) and ultraviolet disinfection. The product was then characterized by analysis of inorganic and organic substances, pesticides, physical properties and volatiles profile. The technical viability of "orange water" was proved by the results obtained. As for the sensory analysis, the acceptance was about 50%, when the "orange water" was produced from evaporated water from concentrated orange juice at the end of harvest. Furthermore, acceptance trends observed were above 90% when the product was processed from fruit crop peak. To evaluate the economic feasibility, it was prepared a hypothetical industrial facility draft for production of 1000 liters / hour of bottled orange water. The equilibrium point achieved with the costs and revenues recommended a capacity utilization of more than 57.04%; the chance of success was revealed due to significant internal rate of return of 28.30% per year and a capital recovery time around 3.5 years. About the citrus industry wastewater treatment aiming reuse, the performed estimation showed that the resources generated by the orange water producing plant are not enough to deploy and operate a wastewater treatment plant in the current scenario, if MBR membrane is used, but it may contribute only partially for such deployment / Doutorado / Agua e Solo / Doutora em Engenharia Agrícola
74

Rehabilitation of the Orange River Mouth Salt Marsh : seed, wind and sediment characteristics

Shaw, Gregory Alan January 2007 (has links)
The Orange River is an important source of freshwater and like many other wetlands in semi-arid regions, supports various social (Spurgeon, 1998), economic (Spurgeon, 1998; Bornman et al., 2005) and ecological functions. The saltmarsh at the Orange River Mouth has become degraded over time following numerous anthropogenic impacts. As a result the Transboundary RAMSAR site was placed on the Montreux record emphasising the importance for rehabilitation. The potential of the marsh for natural rehabilitation was assessed through three physical factors which were considered to have the most influence on the saltmarsh i.e. 1) sediment 2) water 3) wind. Three sampling areas were chosen to investigate the sediment characteristics of the ORM saltmarsh and the suitability for seed germination and adult survival. Site A was representative of the general marsh area, Site B was thought to have favourable sediment conditions for saltmarsh growth because of the large numbers of seedlings and Site C was prone to inundation by wind blown sediment. The sites were sampled in 2005 (dry conditions) and in 2006 after high rainfall and river flooding. Electrical conductivity (EC) of the sediment throughout the marsh was hypersaline in many instances above the tolerance range for S. pillansii (> 80 mS.cm-1) The freshwater event in 2006 lowered salinity significantly in two of the three sites. Differences in sediment characteristics were also compared for three habitats i.e. driftlines, open sites and under vegetation. Driftlines (C. coronopifolia = 872 seedlings m-2; S. pillansii = 1296 seedlings m-2) and the microhabitat associated with adult plants (C. coronopifolia = 803 seedlings m-2; S. pillansii = 721 seedlings m-2) created favourable conditions for seedling growth, however open unvegetated (C. coronopifolia = 56 seedlings m-2; S. pillansii = 49 seedlings m-2) areas had significantly lower seedling density. Due to the marsh currently being in a desertified state this study aimed to establish whether the remaining vegetation could produce enough seed to revegetate the marsh. Laboratory studies indicated that seeds of both species germinated best in freshwater (0 psu). The germination of S. pillansii seeds was 40 percent at 0 psu compared to 5 percent at 35 psu. After storage under hypersaline conditions (35 psu) C. coronopifolia showed 100 percent seed germination when returned to freshwater whereas storage at 70 psu decreased the viability of S. pillansii seeds. The plants are producing adequate seed that will allow for regrowth and rehabilitation if sediment and groundwater characteristics are suitable for seed germination, seedling growth and adult survival. However the increase in bare areas at the Orange River mouth as a result of salt marsh dieback has increased the available sediment source. The wind blown sediment has covered large areas of the remaining adult salt marsh vegetation, particularly in the northern corner at Site C, causing further die-back.
75

Nano silver-iron-reduced graphene oxide modified titanium dioxide photocatalyst for the remediation of organic dye in water systems

Sass, Danielle Thandi January 2018 (has links)
Magister Scientiae - MSc (Chemistry) / Drinking water with high concentrations of inorganic and organic contaminants can cause adverse health defects. Specifically methyl orange dye is an organic water contaminant that has been known (along with others like methyl blue etc.) to have an increase in our water systems over the past few years due to increasing demand in industrial processes. It is therefore of utmost importance to remediate organic contaminants and ultimately enable prevention. The contaminants can be removed by photocatalysis. Anatase TiO2 is known for its photocatalytic degradation of environmental pollutants and photoelectro-chemical conversion of solar energy. However its application is limited since it is a wide band gap semiconductor, (Eg = 3.2 eV). The following study deals with the enhancement of the photocatalytic properties of TiO2 for remediation of organic water contaminants.
76

Integrating hydro-climatic hazards and climate changes as a tool for adaptive water resources management in the Orange River Catchment.

Knoesen, Darryn Marc. January 2012 (has links)
The world’s freshwater resources are being placed under increasing pressure owing to growth in population, economic development, improved standards of living, agricultural intensification (linked mainly to irrigation), pollution and mismanagement of available freshwater resources. Already, in many parts of the Orange River Catchment, water availability has reached a critical stage. It has become increasingly evident that water related problems can no longer be resolved by water managers alone, owing to the problems becoming more interconnected with other development related issues, as well as with social, economic, environmental, legal and political factors. With the advent of climate change and the likelihood of increases in extreme events, water managers’ awareness of uncertainties and critical reflections on the adequacy of current management approaches is increasing. In order to manage water resources effectively a more holistic approach is required than has hitherto been the case, in which technological, social and economic development are linked with the protection of natural ecosystems and with dependable projections of future climatic conditions. To assess the climate risk connected with rural and urban water management, and to develop adaptive strategies that can respond to an increasingly variable climate that is projected into the future and help to reduce adverse impacts, it is necessary to make connections between climate related hazards, climate forecasts as well as climate change, and the planning, design, operation, maintenance, and rehabilitation of water related infrastructure. Therefore, adaptive water resources management (AWRM), which in essence is “learning by doing”, is believed to be a timely extension of the integrated water resources management (IWRM) approach as it acknowledges uncertainty and is flexible in that it allows for the adjustment of actions based on information learned about the system. Furthermore, it is suggested that climate risk management be imbedded within the AWRM framework. The objective of the research presented in this thesis is to develop techniques to integrate state-of-the-art climate projection scenarios – which forms part of the first step of the adaptive management cycle – downscaled to the regional/local scale, with hydro-climatic hazard determination – which forms part of the first step in the risk management process – in order to simulate projected impacts of climate change on hydro-climatic hazards in the Orange River Catchment (defined in this study as those areas of the catchment that exist within South Africa and Lesotho). The techniques developed and the results presented in this study can be used by decision-makers in the water sector in order to make informed proactive decisions as a response to projected future impacts of hydro-climatic hazards – all within a framework of AWRM. Steps towards fulfilling the above-mentioned objective begins by way of a comprehensive literature review; firstly of the study area, where it is identified that the Orange River Catchment is, in hydro-climatic terms, already a high risk environment; and secondly, of the relevant concepts involved which are, for this specific study, those pertaining to climate change, and the associated potential hydro-climatic impacts. These include risk management and its components, in order identify how hazard identification fits into the broader concept of risk management; and water resources management practices, in order to place the issues identified above within the context of AWRM. This study uses future projections of climate from five General Circulation Models, all using the SRES A2 emission scenario. By and large, however, where techniques developed in this study are demonstrated, this is done using the projections from the ECHAM5/MPI-OM GCM which, relative to the other four available GCMs, is considered to provide “middle of the road” projections of future climates over southern Africa. These climate projections are used in conjunction with the locally developed and widely verified ACRU hydrological model, as well as a newly developed hydro-climatic database at a finer spatial resolution than was available before, to make projections regarding the likelihood and severity of hydro-climatic hazards that may occur in the Orange River Catchment. The impacts of climate change on hydro-climatic hazards, viz. design rainfalls, design floods, droughts and sediment yields are investigated, with the results including a quantitative uncertainty analysis, by way of an index of concurrence from multiple GCM projections, for each of the respective analyses. A new methodology for the calculation of short duration (< 24 hour) design rainfalls from daily GCM rainfall projections is developed in this study. The methodology utilises an index storm approach and is based on L-moments, allowing for short duration design rainfalls to be estimated at any location in South Africa for which daily GCM rainfall projections exist. The results from the five GCMs used in this study indicate the following possible impacts of climate change on hydro-climatic hazards in the Orange River Catchment: · Design rainfalls of both short and long duration are, by and large, projected to increase by the intermediate future period represented by 2046 - 2065, and even more so by the more distant future period 2081 - 2100. · Design floods are, by and large, projected to increase into the intermediate future, and even more into the more distant future; with these increases being larger than those projected for design rainfalls. · Both meteorological and hydrological droughts are projected to decrease, both in terms of magnitude and frequency, by the period 2046 - 2065, with further decreases projected for the period 2081 - 2100. Where increases in meteorological and hydrological droughts are projected to occur, these are most likely to be in the western, drier regions of the catchment. · Annual sediment yields, as well as their year-to-year variability, are projected to increase by the period 2046 - 2065, and even more so by the period 2081 - 2100. These increases are most likely to occur in the higher rainfall, and especially in the steeper, regions in the east of the catchment. Additionally, with respect to the above-mentioned hydro-climatic hazards, it was found that: · The statistic chosen to describe inter-annual variability of hydro-climatic variables may create different perceptions of the projected future hydroclimatic environment and, hence, whether or not the water manager would decide whether adaptive action is necessary to manage future variability. · There is greater uncertainty amongst the GCMs used in this study when estimating design events (rainfall and streamflow) for shorter durations and longer return periods, indicating that GCMs may still be failing to simulate individual extreme events. · The spatial distribution of projected changes in meteorological and hydrological droughts are different, owing to the complexities introduced by the hydrological system · Many areas may be exposed to increases in hydrological hazards (i.e. hydrological drought, floods and/or sediment yields) because, where one extreme is projected to decrease, one of the others is often projected to increase. The thesis is concluded with recommendations for future research in the climate change and hydrological fields, based on the experiences gained in undertaking this study. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
77

Urban-Urban and peri-urban agriculture as a poverty alleviation strategy among low income households : the case of Orange Farm, South Johannesburg

Onyango, Calory Larr 01 1900 (has links)
Urban and peri-urban agriculture is a strategy that can be adapted by low income households in Orange Farm to meet their food and nutritional requirements. The practice is a basis upon which poor families can enhance their incomes by producing part of their food needs, hence saving money for use on other livelihood obligations. This dissertation discusses the importance of urban and peri-urban agriculture as a method easily available to low income families residing in informal settlements to access food and incomes. Urban agriculture is examined in the context of poverty alleviation. A descriptive and quantitative assessment of the salient variables of the practice in the area is attempted in order to give an insight of the potential role the sector can play in eliminating poverty, enhancing incomes and creating employment. The study shows that participation in urban farming can impact significantly on poverty conditions and improve livelihoods. / MA (Development Studies)
78

"Because all black people love chicken" : En kvalitativ innehållsanalys av etniska stereotyper i tv-serien Orange is the new black

Sandberg Ericsson, John, Boström, Erik January 2016 (has links)
Studien är en kvalitativ innehållsanalys av den amerikanska tv-serien Orange  is the new black, där vi har undersökt hur etniska stereotyper konstrueras i serien. Orange is the new black har omtalats som en tv-serie som bryter mot många av de klassiska fördomarna kring etniska grupper. Genom att undersöka vilka stereotyper som tidigare har förekommit i media har vi sedan kunnat undersöka hur etniciteter framställs i vårt undersökningsobjekt, hur de framställs i relation till varandra och om serien lyckas utmana gamla stereotyper, och i så fall hur? För att undersöka detta har vi använt semiotik som metod. Problemet som vi ser är att människor påverkas av vad de ser i medierna och att media påverkar hur samhället ser ut. Med hjälp av postkolonial teori och begreppen stereotyp och hegemoni undersöker vi hur en tv-serie kan hjälpa till att styra samhällets strukturer och attityder gentemot andra etniciteter. Den postkoloniala teorin menar att västerländsk kultur ofta är etnocentrisk och bidrar till att skapa klyftor mellan “vi” i väst, och “de” andra.   Vi kom fram till att Orange is the new black bekräftar existerande stereotyper snarare än att bryta mot dem, och att serien i hög grad bidrar till att förstärka skillnaden mellan etniska grupper. Vi har därmed dragit slutsatsen att tv-serien också då påverkar samhällets hegemoni genom att porträttera den vita medelklassen som en grupp som står över afroamerikaner, latinamerikaner, asiater och white trash. Som vidare forskning föreslår vi att fokus förflyttas från innehållet till hur mottagarna uppfattar stereotyper i Orange is the new black.
79

Gas chromatography/olfactometry and descriptive analysis of Valencia orange juice

Shah, Rohan 08 June 1998 (has links)
Heat treated orange juice, both pasteurized and concentrate, are being increasingly consumed in the U.S. Orange juice is primarily heat treated to increase its shelf life, by curbing the growth of microorganisms; and to inactivate pectin methylesterase, which demethylates pectin and leads to cloud loss in the juice. However, because of heat processing, orange juice undergoes undesirable flavor changes that decrease its acceptability to consumers. The objectives of this study were to differentiate between fresh frozen and heat treated orange juice employing descriptive analysis, and to determine by Osme, a gas chromatography-olfactometry (GCO) method, odor active volatiles that were either lacking or created in the heat treated juice. The second objective was to determine how changes in the odor-active volatile profile of heat treated orange juice, relates to changes in the aroma and flavor intensities of the samples as assessed by descriptive analysis. Through descriptive analysis, the panel was successful in significantly (p<0.05) separating the fresh, pasteurized, and concentrate samples. Orange, orange peel, sweet, and grassy descriptors were found to be important for fresh aroma and flavor, while cooked, yam, metallic, tamarind, green bean and artificial orange descriptors were higher in heat treated samples. Using Osme, it was possible to separate fresh frozen from heat treated orange juice, on the basis of their aroma profiles. Fresh frozen samples show a higher concentration of peaks tentatively identified as gamma-butyrolactone, citral, nonanal, carvone, perillaldehyde, carvyl propinate, valencene, and other unidentified peaks possessing descriptors such as floral, lime, citrus, pine, bamboo leaf, metallic, and vinyl. Pasteurized samples show a larger concentration of peaks tentatively identified as hexanol, octanol, nerol / carveol, myrcene, 2-octanone, p-cymene, terpenen-4-ol, betacitronellol, and other unidentified peaks with descriptors such as cilantro, vinyl, melon, mushroom, and metallic. Descriptors such as orange, orange peel, sweet, grapefruit, and grassy are more pronounced in the fresh samples and are similar to the odor descriptors of Osme peaks higher in the fresh samples. Descriptors such as cooked, artificial orange, yam, metallic, tamarind, and green bean are higher in the pasteurized samples, and are similar to the odor descriptors of peaks higher in these samples. / Graduation date: 1999
80

The Changing Geography of Poverty in the U.S. and Its Effect on Food Insecurity: A Closer Look at the Real “O.C.”

Mackey, Mallory 01 January 2017 (has links)
Food insecurity is on the rise throughout the United States. Today more than 11.6% of American household’s face food insecurity. Many of these food insecure households reside in the suburbs. Despite these rising rates of food insecurity, the issue of suburban food insecurity has largely gone unnoticed. In this paper, I use Orange County as a case study to investigate how the rise of poverty in the suburbs relates to the issue of suburban food insecurity. Some questions this paper addresses are: What are the driving forces of poverty in the suburbs? What barriers to food security do suburban residents face and how are they different from urban areas? And lastly, what are the next steps to solving suburban food insecurity?

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