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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.
1

The effect of growth stage and season on the prediction of the metabolisable energy content of herbage

Givens, David Ian January 1990 (has links)
No description available.
2

Economic Policy and Resource Implications of Biofuel Feedstock Production

Adusumilli, Naveen 2012 August 1900 (has links)
Dramatically higher fuel prices and massive petroleum imports from politically unstable countries have contributed to a major national initiative to generate renewable fuels in the United States. Often, such policies are enacted and implemented with huge taxpayer expenditures without due diligence to the consequences. The evaluation of the water quality impacts of converting pastureland to intensive biomass production for fuel in a southern Texas watershed suggest significant increases erosion and nutrient loadings to water bodies. The Best Management Practices (BMPs), cover crop and filter strips when implemented individually failed to produce status-quo reduction levels. Combined BMPs implementation produced improved mitigation, at substantially higher costs, highlighting the issue of sustainability related to the economics of renewable fuels. The estimation of the net energy of biomass ethanol accounting for the production input data indicate a greater than one energy return for biomass crops. However, the policy results indicate that only 70 percent in net contribution to the energy supply is achieved due to relatively lower energy returns compared to conventional fossil fuels. In addition, because the ethanol produced has to have the energy used deleted from the total, the cost of producing a gallon of biomass ethanol is substantially higher than that of gasoline. The impacts of an exogenously-specified biofuel mandate fulfilled by the production of a dedicated biomass crop and its consequent effects on commodity prices and overall welfare are estimated. Net farm income increased due to an increase in crop prices; however, both consumer surplus and total surplus decreased. The analysis is extended to estimate the sensitivity of Conservation Reserve Program (CRP) acres returning to crop production and the potential of higher biomass yields. The results indicate that net farm income decreased and consumer surplus increased due to a decrease in crop prices, resulting in an increase in overall welfare. This current research evaluates the unintended consequences of the U.S. energy policy and provides interesting insights of the potential economic and environmental impacts. These results suggest policy makers should be cautious before enacting energy policy and consider multiple alternative energy sources in an economic and financial context to achieve a sustainable energy goal.
3

Repercussão da informação nutricional sobre o comportamento de clientes de restaurantes universitários\" / Repercussion of nutritional information on the behavior of the clients of university restaurants

Silva, Maurea Elena Missio da 05 September 2006 (has links)
Introdução - A informação nutricional do rótulo de embalagem de alimentos tem sido uma estratégia importante para oferecer ao consumidor informações para escolhas mais apropriadas. Partindo desse princípio, os restaurantes administrados pela Coordenadoria de Assistência Social, no ano de 2001, passaram a disponibilizar a informação de valor energético das preparações culinárias oferecidas nos restaurantes de forma a orientar e auxiliar o cliente em sua escolha. Objetivo Avaliar o comportamento de funcionários e alunos que utilizam os restaurantes universitários em relação à informação nutricional e, em especial, referente ao valor energético das preparações culinárias oferecidas nestes. Métodos - Foi utilizada amostra sistemática. Os domínios de estudo foram constituídos por dois estratos de 600 indivíduos cada. O método de investigação foi a entrevista estruturada. As variáveis de estudo foram analisadas de forma descritiva e utilizou-se o teste Qui-quadrado para analisar associações. Resultados. Houve semelhanças entre os estratos de alunos e funcionários com maior tempo de educação formal. Não houve associação entre ler as informações nutricionais do rótulo de embalagem de alimentos e o valor energético das preparações culinárias oferecidas pelos restaurantes. A utilização da informação nutricional esteve associada a, anos de educação formal, excesso de peso, prática de atividade física esportiva, tipos de fontes de informação sobre alimentação e nutrição. Conclusão. Observou-se ser esta pesquisa de importante natureza, uma vez que não foram encontrados trabalhos específicos que avaliassem o comportamento da população universitária sobre a informação nutricional. De modo geral, as mulheres utilizam as duas Resumo informações nutricionais mais que os homens. No caso dos alunos, observouse pouco interesse em relação às duas informações. Entre os funcionários de menor tempo de educação formal, verificou-se maior interesse na informação de valor energético das preparações culinárias, diferente dos funcionários com maior tempo de educação formal, que lêem mais as informações nutricionais do rótulo de embalagem de alimentos / The nutritional information on the labels on the packaging of foodstuffs has proved an important strategy in offering the consumer such information to make the most appropriate choices. On this basis, the restaurants managed by the Coordenadoria de Assistência Social began, in 2001, to make available to their clients information regarding the energy value of the food prepared so as to guide and help them in their choices. Objective. To assess the behavior of the staff members and students who make use of university restaurants in their response to the nutritional information provided, especially as regards the energy value of the food prepared and provided in these restaurants. Methods. Systematic sampling was used. The universe of study consisted of two strata of 600 individuals each. The structured interview was used as the method of investigation. The study variables were analyzed descriptively and the chi-squared test was used to analyze the associations. Results. There were similarities between the strata of students and staff with higher levels of education. There was no association between the reading of the labels on the packaging of foodstuffs and the energy value of the food prepared and offered by the restaurant. The use made of the nutritional information provided was associated with the level of education, over-weight, practice of physical sporting activity and kinds of sources of information on feeding habits and nutrition. Conclusion. It is clear that this research is important, as no specific studies which attempt to assess behavior related to nutritional information in a university population are available. Generally speaking, women use both kinds of Abstract information more than men. As regards the students, little interest was show in either kind of information. Among the staff of low level of education a greater interest was found in energy value information regarding the food served in the university restaurant than among the staff of higher levels of education who read the information on the packaging of foodstuffs more frequently
4

Management of tall fescue, cocksfoot and reed canary grass swards for biogas, biomass quality and energy value / Nendrinių eraičinų, paprastųjų šunažolių ir nendrinių dryžučių auginimo biodujoms būdai, biomasės kokybė ir energinė vertė

Tilvikienė, Vita 15 November 2012 (has links)
Research objective The study was designed to investigate biomass production of tall fescue, cocksfoot, and reed canary grass and the quality of raw material for biogas as influenced by sward fertilization with different rates of nitrogen and different number of cuts per season and to establish the effect of fertilization with digestate on cocksfoot biomass production and quality. Research tasks: • to estimate the productivity of tall fescue, cocksfoot and reed canary grass, fertilized with different nitrogen rates, for biogas; • to assess the effect of cutting frequency and fertilization rate of tall fescue, cocksfoot and reed canary grass on the quality composition of biomass for biogas and biogas potential; • to estimate agroecological value of perennial grasses; • to determine the energy potential of biomass of the tested perennial grasses used for biogas production and to identify the energy balance of raw material preparation for biogas. Research subject - tall fescue (Festuca arundinacea Schreb.), cocksfoot (Dactylis glomerata L.), reed canary grass (Phalaris arundinacea L.). Originality of the research work. One of the potential raw materials for biogas production is biomass of perennial grasses. Each grass species differs in growth rhythm and rate, demand for nutrients, and other characteristics, therefore the amount of biomass is highly dependent on specific growing conditions and cultivation technologies that have to ensure the quality of raw material best suited... [to full text] / Tyrimo tikslas – ištirti nendrinių eraičinų, paprastųjų šunažolių ir nendrinių dryžučių biomasės kiekį bei žaliavos biodujoms kokybę pagal skirtingas azoto normas tręštuose žolynuose, taikant nevienodą pjūčių skaičių per sezoną ir nustatyti tręšimo biosubstratu įtaką paprastųjų šunažolių biomasės kiekiui bei kokybei. Tyrimo uždaviniai: • įvertinti biodujoms auginamų nendrinių eraičinų, paprastųjų šunažolių ir nendrinių dryžučių produktyvumą, juos tręšiant skirtingomis azoto normomis; • nustatyti nendrinių eraičinų, paprastųjų šunažolių ir nendrinių dryžučių pjūčių dažnumo ir tręšimo azotu įtaką biomasės biodujoms kokybinei sudėčiai bei dujų potencialui; • nustatyti tirtų daugiamečių žolių auginimo agroekologinę vertę; • įvertinti biomasės naudojimo biodujų gamybai energinį potencialą ir žaliavos paruošimo biodujoms energijos balansą. Tyrimo objektas – nendrinis eraičinas (Festuca arundinacea Schreb.), paprastoji šunažolė (Dactylis glomerata L.), nendrinis dryžutis (Phalaris arundinacea L.) Mokslinis naujumas. Viena iš potencialių žaliavų biodujų gamybai yra daugiamečių žolių biomasė. Tačiau kiekviena žolių rūšis nuo kitų skiriasi savitu augimo ritmu, trukme, maisto medžiagų poreikiu ir kitomis savybėmis, todėl biomasės kiekis labai priklauso nuo konkrečių augimo sąlygų ir auginimo technologijų, o kokybė turėtų būti tokia, kad būtų tinkamiausia pagal numatomą žaliavos panaudojimo paskirtį. Šio tyrimo metu nustatyta, kad vidutinių platumų klimato zonos šiaurinėje dalyje... [toliau žr. visą tekstą]
5

Repercussão da informação nutricional sobre o comportamento de clientes de restaurantes universitários\" / Repercussion of nutritional information on the behavior of the clients of university restaurants

Maurea Elena Missio da Silva 05 September 2006 (has links)
Introdução - A informação nutricional do rótulo de embalagem de alimentos tem sido uma estratégia importante para oferecer ao consumidor informações para escolhas mais apropriadas. Partindo desse princípio, os restaurantes administrados pela Coordenadoria de Assistência Social, no ano de 2001, passaram a disponibilizar a informação de valor energético das preparações culinárias oferecidas nos restaurantes de forma a orientar e auxiliar o cliente em sua escolha. Objetivo Avaliar o comportamento de funcionários e alunos que utilizam os restaurantes universitários em relação à informação nutricional e, em especial, referente ao valor energético das preparações culinárias oferecidas nestes. Métodos - Foi utilizada amostra sistemática. Os domínios de estudo foram constituídos por dois estratos de 600 indivíduos cada. O método de investigação foi a entrevista estruturada. As variáveis de estudo foram analisadas de forma descritiva e utilizou-se o teste Qui-quadrado para analisar associações. Resultados. Houve semelhanças entre os estratos de alunos e funcionários com maior tempo de educação formal. Não houve associação entre ler as informações nutricionais do rótulo de embalagem de alimentos e o valor energético das preparações culinárias oferecidas pelos restaurantes. A utilização da informação nutricional esteve associada a, anos de educação formal, excesso de peso, prática de atividade física esportiva, tipos de fontes de informação sobre alimentação e nutrição. Conclusão. Observou-se ser esta pesquisa de importante natureza, uma vez que não foram encontrados trabalhos específicos que avaliassem o comportamento da população universitária sobre a informação nutricional. De modo geral, as mulheres utilizam as duas Resumo informações nutricionais mais que os homens. No caso dos alunos, observouse pouco interesse em relação às duas informações. Entre os funcionários de menor tempo de educação formal, verificou-se maior interesse na informação de valor energético das preparações culinárias, diferente dos funcionários com maior tempo de educação formal, que lêem mais as informações nutricionais do rótulo de embalagem de alimentos / The nutritional information on the labels on the packaging of foodstuffs has proved an important strategy in offering the consumer such information to make the most appropriate choices. On this basis, the restaurants managed by the Coordenadoria de Assistência Social began, in 2001, to make available to their clients information regarding the energy value of the food prepared so as to guide and help them in their choices. Objective. To assess the behavior of the staff members and students who make use of university restaurants in their response to the nutritional information provided, especially as regards the energy value of the food prepared and provided in these restaurants. Methods. Systematic sampling was used. The universe of study consisted of two strata of 600 individuals each. The structured interview was used as the method of investigation. The study variables were analyzed descriptively and the chi-squared test was used to analyze the associations. Results. There were similarities between the strata of students and staff with higher levels of education. There was no association between the reading of the labels on the packaging of foodstuffs and the energy value of the food prepared and offered by the restaurant. The use made of the nutritional information provided was associated with the level of education, over-weight, practice of physical sporting activity and kinds of sources of information on feeding habits and nutrition. Conclusion. It is clear that this research is important, as no specific studies which attempt to assess behavior related to nutritional information in a university population are available. Generally speaking, women use both kinds of Abstract information more than men. As regards the students, little interest was show in either kind of information. Among the staff of low level of education a greater interest was found in energy value information regarding the food served in the university restaurant than among the staff of higher levels of education who read the information on the packaging of foodstuffs more frequently
6

The Development and Evaluation of Biofuel Production Systems on Marginal Land

January 2013 (has links)
abstract: The consumption of feedstocks from agriculture and forestry by current biofuel production has raised concerns about food security and land availability. In the meantime, intensive human activities have created a large amount of marginal lands that require management. This study investigated the viability of aligning land management with biofuel production on marginal lands. Biofuel crop production on two types of marginal lands, namely urban vacant lots and abandoned mine lands (AMLs), were assessed. The investigation of biofuel production on urban marginal land was carried out in Pittsburgh between 2008 and 2011, using the sunflower gardens developed by a Pittsburgh non-profit as an example. Results showed that the crops from urban marginal lands were safe for biofuel. The crop yield was 20% of that on agricultural land while the low input agriculture was used in crop cultivation. The energy balance analysis demonstrated that the sunflower gardens could produce a net energy return even at the current low yield. Biofuel production on AML was assessed from experiments conducted in a greenhouse for sunflower, soybean, corn, canola and camelina. The research successfully created an industrial symbiosis by using bauxite as soil amendment to enable plant growth on very acidic mine refuse. Phytoremediation and soil amendments were found to be able to effectively reduce contamination in the AML and its runoff. Results from this research supported that biofuel production on marginal lands could be a unique and feasible option for cultivating biofuel feedstocks. / Dissertation/Thesis / M.S. Sustainability 2013
7

Characterization of Forest Harvest Residue from the Great Lakes-St Lawrence Forests of South-eastern Ontario

Acquah, Gifty Ewurama 14 December 2010 (has links)
The use of fossil derived products and the environmental and economic problems associated with them have made a shift to abundant renewable resources such as forest biomass more attractive. However before forest biomass can be used as a resource, its properties must be known. This study determined the physical properties of heterogeneous biomass residues produced during harvesting on two operational forest sites within the Great Lakes-St Lawrence forest of south-eastern Ontario. Properties measured were moisture content, size distribution, bulk density, and wood-to-bark ratio; also thermo-chemical properties including elemental composition, thermal reactivity and energy content were measured. The effects of forest site and harvest type, storage and position in storage pile, on the properties of biomass were also investigated. Results of the study showed that the various heterogeneous forest harvest residues differed more physically than thermo-chemically for the different variables, and this affected biomass procurement more than the potential utilization options.
8

Maistui skerdžiamų avių kiekiai ir mėsos kokybė / Quantities and quality of sheep meat slaughtering for food

Budreckis, Donatas 18 June 2013 (has links)
Per pastaruosius tris dešimtmečius įvyko daug socialinių, ekonominių pokyčių, padidėjęs visuomenės sąmoningumas keičia gyvenimo būdą ir poreikį aukštesniems gyvenimo standartams. kurie savo ruožtu iškėlė labiau integruoto maisto saugos požiūrio reikalingumą. Pasikeitė žemės ūkio produktų gamybos, perdirbimo, pardavimo ir vartojimo struktūra. Padidėję gyvulinių produktų mainai sudarė sąlygas vartotojams gauti pigesnį ir įvairesnį maistą, bet tapo sunkiau atsekti produktų kelią nuo gamintojo iki galutinio vartotojo. Šiandieninė situacija skirtinguose Lietuvos žemės ūkio sektoriuose keičiasi. Mažėjant ūkių, mažėja, kai kurių auginamų gyvulių skaičius. Statistikos departamento duomenimis nurodoma, kad šiuo metu Lietuvoje yra 105 tūkst. ūkių, kuriuose auginami galvijai. 2012 m. pradžiai mūsų šalyje buvo priskaičiuota 748 tūkst. galvijų, 9264 tūkst. kiaulių, 9466,3 tūkst. paukščių, 79 tūkst. avių. Sparčiausiai auga paukštienos, ypač kalakutienos paklausa, palaipsniui didėja avienos, ožkienos, triušienos, žvėrienos poreikis. Tai siejama su vartotojų požiūrio į sveikesnį maistą kitimu. Atsakomybė už galutinį produktą, kuris patenka ant vartotojo stalo prasideda nuo pašaro gamintojo ir apima tiekėjus, gamybos įmones, augintojus, aptarnaujantį veterinarijos gydytoją, galimus prekybos tarpininkus, skerdyklas ir produkcijos perdirbimo įmones iki mažmeninės prekybos. Pirmoje vietoje turi būti saugumas, stabilumas ir skaidrumas visuose gamybos lygmenyse, taip pat duomenų perdavimo... [toliau žr. visą tekstą] / This final study is written in the Lithuanian language, containing 59 pages and includes: an introduction, literature review, materials and methods, results, conclusions, a list of used literature including references 140, tables 12 and pictures 4. Many social and economical changes have occurred within the three recent decades, increased consciousness of the society changes the life style and the need for higher standards of life, they subsequently revealed the necessity of more integrated attitude towards food safety. The structure of production, processing, sales and consumption of agricultural products has changed. Increased exchange of animal products allowed users to get cheaper food and bigger variety thereof, but tracing the path of products from the manufacturer to the end user became more difficult. Today the situation in different sectors of Lithuanian agriculture is changing. As the amount of farms is decreasing, the amount of some of the bred animals is decreasing as well. According to the data from the Department of Statistics, there currently are 105000 farms breeding cattle in Lithuania. In the beginning of 2012, there were 748000 cattle, 9264000 pigs, 9466300 birds, 79000 sheep in our country. The demand for poultry, especially turkey, is increasing the most, the need for sheep meat, goat meat, rabbit meat, game meat is gradually increasing. It is associated with the change of attitude of users towards healthier food. Responsibility for the final product... [to full text]
9

Characterization of Forest Harvest Residue from the Great Lakes-St Lawrence Forests of South-eastern Ontario

Acquah, Gifty Ewurama 14 December 2010 (has links)
The use of fossil derived products and the environmental and economic problems associated with them have made a shift to abundant renewable resources such as forest biomass more attractive. However before forest biomass can be used as a resource, its properties must be known. This study determined the physical properties of heterogeneous biomass residues produced during harvesting on two operational forest sites within the Great Lakes-St Lawrence forest of south-eastern Ontario. Properties measured were moisture content, size distribution, bulk density, and wood-to-bark ratio; also thermo-chemical properties including elemental composition, thermal reactivity and energy content were measured. The effects of forest site and harvest type, storage and position in storage pile, on the properties of biomass were also investigated. Results of the study showed that the various heterogeneous forest harvest residues differed more physically than thermo-chemically for the different variables, and this affected biomass procurement more than the potential utilization options.
10

Avaliação nutricional do farelo de algodão para frangos de cortes

CARVALHO, Clêidida Barros de 26 February 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-03-23T14:54:25Z No. of bitstreams: 1 Cleidida Barros de Carvalho.pdf: 160485 bytes, checksum: 2fb7c27631a436d3bb1f68649141041c (MD5) / Made available in DSpace on 2017-03-23T14:54:25Z (GMT). No. of bitstreams: 1 Cleidida Barros de Carvalho.pdf: 160485 bytes, checksum: 2fb7c27631a436d3bb1f68649141041c (MD5) Previous issue date: 2008-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of the research was determine chemical and energetic composition of the cottonseed meal and evaluate its inclusion on performance of poultry. The chemical, energetic and aminoacidic composition was determined using the total excreta collection method, twice a day. It was used ferric oxide to mark the beginning and the end of the collection. The level of inclusion of test feed in reference feed was 20%. The performance was evaluated with the inclusion of cottonseed meal in a period of 9 to 42 days. During the first nine days the poultries received pre-initial feed common to all birds. Beginning on the ninth day, birds were subjected to an experimental diet with substitution levels of 3%, 6%, 9% and 12% of the corn and the soy meal of reference feed. The cottonseed meal presented 95,91% of dry matter, 9,8% of fat, 27% of crude protein, 4,6% of ash, 4.867 kcal/kg of crude energy, 1,32% of lysine and 0,35% of metionine. The determined value of apparent metabolizable energy corrected to nitrogen was 1.188 kcal/kg. It was not observed effect in the performance and carcass return of the poultry at 42 days of age. / Realizou-se dois experimentos, sendo o primeiro com uma duração 10 dias destinados ao ensaio de digestibilidade e o segundo com duração de 42 dias destinados ao ensaio de desempenho. Ambos foram conduzidos no Departamento de Zootecnia da Universidade Federal Rural de Pernambuco, com o objetivo de avaliar a composição energética e a utilização do farelo de algodão na alimentação de frangos de corte. Foram realizadas análises para a determinação da composição química e posteriormente um ensaio de digestibilidade para a determinação da energia metabolizável aparente e aparente corrigida para nitrogênio. A partir desses dados foi montado um ensaio para medir o desempenho de frangos de corte através de análises de ganho de peso, consumo de ração, conversão alimentar e rendimento de carcaça. Foi utilizado o delineamento experimental inteiramente casualizado nos dois ensaios. O valor de energia metabolizável aparente corrigida para nitrogênio determinado foi 1.188 kcal/kg, e não se observou diferenças significativas nas análises de desempenho e rendimento de carcaça dos frangos aos 42 dias de idade.

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