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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.
121

Near-Infrared Spectral Measurements and Multivariate Analysis for Predicting Glass Contamination of Boiler Fuel

Winn, Olivia, Thekkemadathil Sivaram, Kiran January 2017 (has links)
This degree project investigates how glass contamination in refuse-derived fuel for a fluidised bed boiler can be detected using near-infrared spectroscopy. It is motivated by the potential to reduce greenhouse gas emissions by replacing fossil fuels with refuse-derived fuel. The intent was to develop a multivariate predictive model of near-infrared spectral data to detect the presence of glass cullet against a background material that represents refuse-derived fuel. Existing literature was reviewed to confirm the usage of near-infrared spectroscopy as a sensing technology and determine the necessity of glass detection. Four unique background materials were chosen to represent the main components in municipal solid waste: wood shavings, shredded coconut, dry rice and whey powder. Samples of glass mixed with the background material were imaged using near-infrared spectroscopy, the resulting data was pre-processed and analysed using partial least squares regression. It was shown that a predictive model for quantifying coloured glass cullet content in one of several background materials were reasonably accurate with a validation coefficient of determination of 0.81 between the predicted and reference data. Models that used data from a single type of background material, wood shavings, were more accurate. Models for quantifying clear glass cullet content were significantly less accurate. These types of models could be applied to predict coloured glass content in different kinds of background materials. However, the presence of clear glass in municipal solid waste, and thus refuse-derived fuel, limit the opportunities to apply these methods to the detection of glass contamination in fuel.
122

Avfall på förskolor i Umeå kommun : Vilka faktorer påverkar mängden brännbart avfall, matavfall samt källsorterat material?

Åberg, Lina January 2017 (has links)
It is of major importance with proper waste management to reduce the risk for toxic substances to affect environment and reducing the need for natural resources. Umeå municipality has developed a waste plan to reduce the impact on environment and human health. One of the goals was to fraction all garbage disposals until 2016 at the different administration in the municipality including the preschools. This study investigated pre-conditions and the personals attitude for separate waste, awareness of the waste plane content and if either of these parameters may affect the amount of separated materials at nine selected pre-schools. Web-based surveys were distributed to the personal and observational studies were done at all included preschools. There were significant differences between preschools according to combustible waste, food waste and source-sorted material. It was no significant association between the amount of sorted garbage disposal and the attitude to fractionate, practical conditions and knowledge about the waste plan. Although, the study does not provide a general picture of all preschools in the municipality, the results indicate that better knowledge and information about the importance of separating waste and the waste plan are needed. It´s also necessary to clarify the responsibility between the various actors in order to improve the results over time.
123

Evaluation of the Economic, Social, and Biological Feasibility of Bioconverting Food Wastes with the Black Soldier Fly (Hermetia illucens)

Barry, Tami 08 1900 (has links)
Food waste in the waste stream is becoming an important aspect of integrated waste management systems. Current efforts are composting and animal feeding. However, these food waste disposal practices rely on slow thermodynamic processes of composting or finding farmers with domestic animals capable of consuming the food wastes. Bioconversion, a potential alternative, is a waste management practice that converts food waste to insect larval biomass and organic residue. This project uses a native and common non-pest insect in Texas, the black soldier fly, which processes large quantities of food wastes, as well as animal wastes and sewage in its larval stage. The goal of this research is to facilitate the identification and development of the practical parameters of bioconversion methods at a large cafeteria. Three major factors were selected to evaluate the practicality of a bioconversion system: (1) the biological constraints on the species; (2) the economic costs and benefits for the local community; (3) the perception of and interaction between the public and management agencies with respect to the bioconversion process. Results indicate that bioconversion is feasible on all levels. Larvae tolerate and consume food waste as well as used cooking grease, reducing the overall waste volume by 30-70% in a series of experiments, with an average reduction of 50%. The economical benefits are reduced collection costs and profit from the sale of pupae as a feedstuff, which could amount to as much as $1,200 per month under optimal conditions. Social acceptance is possible, but requires education of the public, specifically targeting school children. Potential impediments to social acceptance include historical attitudes and ignorance, which could be overcome through effective educational efforts.
124

Characterization of Souring in Anaerobic Co-digestion Reactors Loaded with Thickened Sludge, Food Waste, and Fats, Oils and Grease Waste

January 2020 (has links)
abstract: Seeking to address sustainability issues associated with food waste (FW), and fat, oil, and grease (FOG) waste disposal, the City of Mesa commissioned the Biodesign Swette Center for Environmental Biotechnology (BSCEB) at Arizona State University (ASU) to study to the impact of implementing FW/FOG co-digestion at the wastewater treatment plant (WWTP). A key issue for the study was the “souring” of the anaerobic digesters (ADs), which means that the microorganism responsible for organic degradation were deactivated, causing failure of the AD. Several bench-scale reactors soured after the introduction of the FW/FOG feed streams. By comparing measurements from stable with measurements from the souring reactors, I identified two different circumstances responsible for souring events. One set of reactors soured rapidly after the introduction of FW/FOG due to the digester’s hydraulic retention times (HRT) becoming too short for stable operation. A second set of reactors soured after a long period of stability due to steady accumulation of fatty acids (FAs) that depleted bicarbonate alkalinity. FA accumulation was caused by the incomplete hydrolysis/fermentation of feedstock protein, leading to insufficient release of ammonium (NH4+). In contrast, carbohydrates were more rapidly hydrolyzed and fermented to FAs. The most important contribution of my research is that I identified several leading indicators of souring. In all cases of souring, the accumulation of soluble chemical oxygen demand (SCOD) was an early and easily quantified indicator. A shift in effluent FA concentrations from shorter to longer species also portended souring. A reduction in the yield of methane (CH4) per mass of volatile suspended solids removed (VSSR) also identified souring conditions, but its variability prevented the methane yield from providing advanced warning to allow intervention. For the rapidly soured reactors, reduced bicarbonate alkalinity was the most useful warning sign, and an increasing ratio of SCOD to bicarbonate alkalinity was the clearest sign of souring. Because I buffered the slow-souring reactors with calcium carbonate (CaCO3), I could not rely on bicarbonate alkalinity as an indicator, which put a premium on SCOD as the early warning. I implemented two buffering regimes and demonstrated that early and consistent buffering could lead to reactor recovery. / Dissertation/Thesis / Masters Thesis East Asian Languages and Civilizations 2020
125

Sustainability in Cooking Shows: A qualitative content analysis on framing of sustainability in the cooking show MasterChef Germany and MasterChef US

Mettke, Laura January 2020 (has links)
Many environmental organisations are trying to counter the negative effects of climate change. The film- and television industry are increasingly becoming the focus of attention, because, although it repeatedly advocates sustainability, it often gets lost in its own productions. The presentation of sustainability is often not visible or clearly recognizable by the viewer. Cooking shows are often criticised by the public for being environmentally friendly in terms of food waste.The goal of this research is to determine how sustainability is presented in cooking shows in Germany and the USA. For this purpose, the following research question is asked: How is sustainability framed in the television cooking series MasterChef US and Germany? And is there a difference between those two countries?The theoretical framework is presented by the framing theory of Erving Goffmann (1974), with the use of this approach sustainability was framed in TV shows and used for the analysis and its results. To answer the research question, a qualitative content analysis was carried out, which analyses both the German and the American version of MasterChef in 2018/2019. The research was divided into indirect and direct events. The results of the study show that the German MasterChef included significantly more sustainable topics than the American one. This confirms that there is a significant difference in the cooking shows between the two countries.
126

Environmental education through sustainable school food waste management in the Vhembe District, Limpopo

Maphaha, Matodzi Hellen 08 August 2020 (has links)
This qualitative case study focuses on identifying factors that could either enable or constrain sustainable food waste management as a form of environmental education (EE) in the participating schools. The study was motivated by the observation that the National School Nutrition Program (NSNP) that was introduced by the Department of Basic Education to support learners from disadvantaged backgrounds with nutritious food was causing pollution in some schools due to inadequate discarding of food leftovers. The purpose of the study was to develop recommendations towards a sustainable means of managing this food waste in the schools. As an Agricultural Science educator, I wanted to explore the possibilities of enhancing environmental education in schools through sustainable food waste management. While research has been conducted about food waste management and how this is an environmental concern, little has been written about it as it relates to environmental education and sustainability in schools. Hence, this study sought to contribute knowledge to this gap. To achieve this aim, this study followed a descriptive case study design, framed by the value-belief-norm (VBN) theory. Three schools in Vhembe district, Limpopo, were conveniently selected, and the NSNP food coordinator of each selected school, one food handler, two learners, two educators and two SGB members from each sampled school were purposively sampled to get rich information from them about sustainable school food waste management. Data were collected through semi-structured, face-to-face interviews and observations. The findings indicate the various ways in which food waste could be managed in these schools, such as recycling through composting, reusing by community farmers, and reducing the amount of possible food waste. The study also found environmental education to be a key element in which the schools could invest to sustainably and effectively manage food waste. / Educational Studies / M. Ed. (Environmental Education)
127

Development of a Humidity-Resistant Coating to Impart High Oxygen Barrier Performance to Food Packaging Films

Cox, Ryan Yinghua 01 June 2017 (has links)
Oxygen barrier coatings have the potential to greatly extend the lifetime of certain food products by incorporating them into existing food packaging. Present technologies face definite challenges of maintaining high performance, while attaining simple and inexpensive preparation methods. The oxygen barrier effect obtained with these coatings is also susceptible to a plasticization effect when exposed to high humidity, since water vapor molecules are readily soluble in typically hydrophilic resins. In this work, we demonstrate a 1 – 2 micron thick oxygen barrier coating, prepared on a 12 micron poly(ethylene terephthalate) substrate, that has oxygen transmission rates as low as 1.44 cc m-2 day-1 under standard conditions and can maintain similar oxygen barrier performance at high humidity. This degree of oxygen barrier meets the standard of 1 – 10 cc m-2 day-1 established for food packaging applications. The coating is prepared through use of sol-gel chemistry between poly(vinyl alcohol) and vinyltrimethoxsilane molecules, which form a strong network resin through hydrolysis and condensation reactions. The formulation of these oxygen barrier coatings allows for variability of solids percentage and viscosity without significant change in performance. The ability to scale up the preparation of these coated films was tested successfully on an industrial flexographic printing press.
128

Valor nutricional de partes convencionais e não convencionais de frutas e hortaliças /

Monteiro, Betânia de Andrade, 1980- January 2008 (has links)
Orientador: Rogério Lopes Vieites / Banca: Flávia Queiroga Aranha de Almeida / Banca: Magali Conceição Monteiro da Silva / Resumo: As informações sobre a composição de vegetais cultivados em solos brasileiros são escassas e mais ainda de partes não convencionais dos alimentos, como cascas, talos e folhas. O desconhecimento dos valores nutricionais dessas partes induz ao mau aproveitamento, ocasionando o desperdício de toneladas de recursos alimentares. Como incentivo ao melhor aproveitamento dos alimentos e como alternativa de dieta nutritiva e de baixo custo, foram verificados o rendimento e as composições de calorias, proteínas, carboidratos, lipídeos, fibras, vitamina C, ferro, cálcio, potássio e umidade em partes convencionais e não convencionais de frutas e hortaliças, amplamente consumidas pela população. Os vegetais foram adquiridos em estabelecimentos comerciais da cidade de Botucatu / SP. As análises foram realizadas em polpas, cascas, flores, folhas ou talos de abacaxi, abóbora, beterraba, brócolis, chuchu, couve, couve-flor, manga, mamão, pepino e salsa. Para comparação entre as médias dos resultados, foi utilizado o teste de Tukey ao nível de 5% de probabilidade, sendo os valores encontrados mais significativos para carboidratos em frutas, proteínas em folhas, lipídeos em pequenas quantidades para todas as partes analisadas, fibras em todas as partes não convencionais, vitamina C em mamão, brócolis e salsa, ferro em folhas e talos de beterraba, cálcio em todas as folhas principalmente a de couve-flor e potássio em cascas de mamão e talos de brócolis e salsa. No presente trabalho pode-se concluir que a utilização integral dos vegetais pode auxiliar no alcance das necessidades nutricionais e na melhora do estado de saúde e qualidade de vida dos indivíduos, principalmente com a ajuda de programas que divulguem essas informações através de receitas práticas para o dia a dia e orientações para uma alimentação mais saudável e econômica. / Abstract: The information about the composition of fruit and vegetables cultivated in Brazilian soil is scarce, and more so in relation to their mostly non-utilized parts, such as skins, peels, stalks and leaves. The lack of knowledge about the nutritional value of these nutriments often leads to their non-utilization, which results in the waste of tons of food resources. In order to stimulate better utilization of food and offer an alternative of nutritive diet at low cost, the yield and the composition of calories, proteins, carbohydrates, lipids, fibres, vitamin C, iron, calcium, potassium and humidity, in both the utilized and non-utilized parts of those fruit and vegetables, which are mainly consumed by the population, were analyzed. The fruit and vegetables were purchased in shops of the city of Botucatu / SP. The analyses were carried out in pulps, skins, flowers, leaves or stalks of pineapple, pumpkin, beetroot, broccoli, chayote, cabbage, cauliflower, mango, papaya, cucumber and parsley. For comparison between the average of the results, the Tukey test, at 5% level of probability, was used and the results found are more significant in relation to carbohydrates in fruit, proteins in leaves, lipids in small quantities for all the parts analysed, fibres in all non-utilized parts, vitamin C in papaya, broccoli and parsley, iron in leaves and stalks of beetroot, calcium in all leaves and mainly in cauliflower leaves and potassium in skins of papaya and stalks of broccoli and parsley. The present study concludes that the integral utilization of fruit and vegetables can assist in obtaining necessary nutrients and improving the state of health and quality of life of individuals, especially with the support of programmes that publicise this information through recipes and guidance towards a more economic and healthy eating. / Mestre
129

Svinn av grönsaker i primärproduktionen : En inblick hos fyra jordbrukare i Gävleborgs län med kopplingar till påverkande kosmetiska preferenser

Nygren, Henrietta, Unefäldt, Kristin January 2020 (has links)
This study provides an insight into the food waste in primary production of vegetables with links to the influencing cosmetic preferences from the consumer level. To study farmers, a qualitative approach has been chosen and a quantitative approach has been taken for the consumer. To study these complex dependency relationships in the food chain, system theory has enabled a holistic overall picture based on these two approaches. The purpose is to identify the problem to increase the understanding of the causes and origin of food waste in primary production. Furthermore, the goal is that the empirical evidence will identify some possible development potential to reduce food waste in primary production. Sweden is an import-dependent country as well as Gävleborg County where, however, there are good development opportunities seen in the arable land where an increased degree of self-sufficiency can reduce the vulnerability in the food supply chain. From this perspective there is a need for an optimized food supply chain where food waste is minimized, self-sufficiency increases and import dependency decreases. Reducing production waste is an important part of the transition towards a more sustainable food production where system efficiency improvements are required at the macro, meso and micro levels. In order to answer what the study intends to investigate, a qualitative interview survey was conducted at four local farmers in Gävleborg County. A supplementary questionnaire survey with end consumers was also established to elucidate influential cosmetic preferences, such as an oblique carrot or scurf on a potato peel. The interviews and questionnaire survey has since been anchored in a literature study. The results of the interview study of the four farmers show that the main causes of the occurrence of food waste are due to severely affected factors such as weather conditions, pests, diseases / fungal infestation and even a small number of quality quality / cosmetic preferences. None of the farmers had any established measurements methods for food waste, which makes the statistical data more difficult. The results of the survey show that there is a knowledge gap regarding crops and their origin where more information would mean that the consumer considered the product choice. The survey showed that there was a willingness to pay more to meet specific purchasing preferences where information can broaden these preferences and allow for more sustainable choices. / Denna studie ger en inblick i uppkommet svinn i primärproduktionen av grönsaker med kopplingar till de påverkande kosmetiska preferenserna från konsumentledet. För att studera jordbrukarna har ett kvalitativ angreppssätt valts och för konsumentledet ett kvantitativt tillvägagångssätt. För att studera dessa komplexa beroenderelationer i livsmedelskedjan har systemteorin möjliggjort en holistisk sammantagen bild utifrån dessa två angreppssätt. Syftet är att identifiera problematiken för att öka förståelsen om svinnets orsaker och uppkomst i primärproduktionen. Vidare är målet att det empiriska underlaget ska leda till att identifiera eventuell utvecklingspotential för att minska svinnet i primärproduktionen. Sverige är ett importberoende land och likaså Gävleborgs län där det också finns goda utvecklingsmöjligheter sett till åkerarealen där en ökad självförsörjningsgrad kan minska sårbarheten i livsmedelskedjan. Utifrån den aspekten finns behov av en optimerad livsmedelskedja där svinn minimeras, självförsörjningsgraden ökar och importberoendet minskar. Att minska produktionssvinnet är en viktig del i omställningen mot en mer hållbar livsmedelsproduktion där systemeffektiviseringar behövs på makro-, meso- och mikronivå. För att besvara det studien ämnar undersöka har en kvalitativ intervjuundersökning genomförts hos fyra lokala jordbrukare i Gävleborgs län. En kompletterande enkätundersökning hos slutkonsument har även upprättats för att belysa påverkande kosmetiska preferenser, till exempel en sned morot eller skorv på potatisskal. Intervju- och enkätundersökningen har sedan förankrats i en litteraturstudie. Resultatet från intervjuundersökningen hos de fyra jordbrukarna visar att huvudorsakerna till uppkommet svinn beror på svårpåverkade faktorer som väderförhållanden, skadedjur, sjukdomar/svampangrepp och även en mindre del kvalitetskrav/kosmetiska preferenser. Ingen av jordbrukarna hade några upprättade mätmetoder för svinnet vilket försvårar den statistiska datan. Resultatet från enkätundersökningen visar att det finns en kunskapslucka om grödor och dess ursprung där mer information skulle innebära att konsumenten övervägde produktvalet. Enkäten visade att det finns vilja att betala mer för att tillgodose specifika inköpspreferenser där information kan utöka dessa preferenser och möjliggöra för mer hållbara val.
130

Food redistribution in Stockholm : A comparative analysis of two scenarios – with and without a food bank

Persson, Anna January 2016 (has links)
Food waste is a serious problem in today’s society. Functional food waste is going to waste treatment while people are suffering from food insecurity. Food redistribution in form of a central food bank which collects food waste at food companies and delivers it to social organizations is a measure to deal with this issue. Stockholm City Mission plans to start up a central food bank in Stockholm and it is this implementation that is of focus in this report. The purpose of this study is to compare two scenarios, with and without a food bank, and evaluate this food bank regarding the possibilities for reduced climate impacts and the economic outcomes of the involving actors (food companies, the central food bank and social organizations). The methods used are literature studies, interviews and a material flow analysis to be able to follow the flows of food through the redistribution system. The results found are that costs can be saved for the actors involved and whether the food bank will go with profit depends on the revenues that can be collected from the involved actors and external investors. Climate impacts are reduced as a result of the implementation, mainly in terms of that functional food waste avoids waste treatment and can be of use.

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