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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.
31

Qualidade de farinhas pré-gelatinizadas, cereais matinais e salgadinhos obtidos por extrusão a partir de grãos quebrados de arroz e polpa de açaí liofilizada ou cúrcuma em pó / Quality of pregelatinized flours, breakfast cereals and salty snacks obtained by extrusion from broken rice grains and lyophilized açaí pulp or turmeric powder

Oliveira, Aryane Ribeiro 19 July 2016 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-09-04T18:31:12Z No. of bitstreams: 2 Dissertação - Aryane Ribeiro Oliveira - 2016.pdf: 5472982 bytes, checksum: 923e2a52a3da18a7b273f39ab9be0601 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-15T14:06:05Z (GMT) No. of bitstreams: 2 Dissertação - Aryane Ribeiro Oliveira - 2016.pdf: 5472982 bytes, checksum: 923e2a52a3da18a7b273f39ab9be0601 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-15T14:06:05Z (GMT). No. of bitstreams: 2 Dissertação - Aryane Ribeiro Oliveira - 2016.pdf: 5472982 bytes, checksum: 923e2a52a3da18a7b273f39ab9be0601 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-07-19 / The by-product of rice processing, which so far has focused its use for animal feed, may be used in the preparation of food products as they have similar nutritional value to whole grain. Furthermore, they can be incorporated into other raw materials to develop new products that add nutritional value to these products. Aiming to demonstrate the quality of this by-product the purpose of this study was to produce breakfast cereals and snacks from different grain replacement levels broken rice (BR) for pulp freeze-dried acaí (PFA) and turmeric powder (TP) respectively evaluating their physical, microbiological and sensory. Moreover, developing pre-gelatinized flours extrusion under mild conditions with different substitutions lyophilized açaí the broken grains of rice and to investigate the effect of the extrusion process under physical, chemical and functional characteristics of the mixture. We used a completely randomized design with 5 treatments. The addition of PFA influenced significantly (p <0.01) all physical parameters of breakfast cereals. Regarding the sensory attributes showed no significant difference between the attributes aroma , flavor and crispness , but the greater acceptance over appearance was obtained in breakfast cereals with 10 %, 15 %, 20 % replacement BR for PFA , while acceptance in color with 15 and 20% .The chosen breakfast cereal with 15 % replacement of broken rice grains per lyophilized acai pulp showed high levels of dietary fiber (9.16 mg 100 g -1) , phenolic compounds (124,50mg 100 g-1) energy value (383.72 kcal 100 g -1) , and anthocyanins (15.21 mg Eq cyanidin -3- glucoside 100 g-1) . The replacement of BR by TP significantly influenced the expansion index, specific volume , hardness and color instrumental parameters , but did not affect the sensory attributes of appearance, color , aroma and crispness .The snacks chosen 6% TP for replacement BR per 100 g, 0.91 g ash, 7.76 g of proteins, lipids 4.78 g, 5.84 g total dietary fiber, 86.94 g carbohydrate, 396.94 kcal, 174.75 mg total phenolic compounds and 6.52% sequestration capacity of DPPH radicals. The pre-gelatinized flour, the extrusion process and affect the chemical properties proximate the mixture, resulting in a decrease in humidity, lipids, fibers, energy, phenolic compounds, antioxidant properties, anthocyanins. The rates of absorption and increased water solubility obtained after extrusion, but the oil absorption index showed no significant differences. The DSC curve shows that the temperature used in the process was sufficient to gelatinization of the starch present in the flour, showing no peak relating to that parameter in the pre-gelatinized flour. Pasting properties were also affected by the extrusion process getting pre - gelatinized flours with higher viscosity and cold paste. Therefore, it is possible to incorporate PFA and TP to broken grains of rice for the production of foods with nutritional, functional and technological value. / Os grãos quebrados oriundos do beneficiamento do arroz (GQA), que tem como destino principal as indútrias de ração, podem também ser utilizados pelas indústrias de alimentos, visto que possuem valor nutricional semelhante ao grão inteiro. Além disso, podem ser misturados com matérias-primas não convencioanais, como a polpa de açai liofilizada (PAL) e a cúrcuma em pó (CP) para desenvolver novos produtos com características nutricionais e funcionais ainda melhores. Neste contexto, o objetivo deste estudo foi produzir cereais matinais e salgadinhos extrusados a partir de diferentes níveis de substituição de GQA por PAL e CP, respectivamente, e avaliar suas características físicas, microbiológicas e aceitação sensorial. Além disso, desenvolver farinhas pré-gelatinizadas em condições brandas de extrusão com diferentes substituições de GQA por PAL, e investigar o efeito do processo de extrusão sob as propriedades físicas, químicas e funcionais da mistura. Foi utilizado um delineamento inteiramente casualizado com 5 tratamentos para cada produto. A adição de PAL influenciou significativamente (p<0,01) todos os parâmetros físicos dos cereais matinais. Em relação aos atributos sensoriais não houve diferença significativa entre os atributos aroma, sabor e crocância, mas a maior aceitação em relação à aparência foi obtida nos cereais matinais com 10%, 15%, 20% de substituição de GQA por PAL, enquanto a aceitação da cor nos com 15 e 20 %. O cereal matinal escolhido com 15% de substituição de grãos quebrados de arroz por polpa de açaí liofilizada apresentou valores elevados de fibra alimentar (9,16 mg 100g-1), compostos fenólicos (124,50 mg 100g-1) valor energético (383,72 kcal 100 g-1), e antocianinas (15,21 mg Eq de cianidina-3-glicosídeo 100 g-1). A substituição dos GQA por CP influenciou significativamente o índice de expansão, o volume específico, a dureza e os parâmetros instrumentais de cor, mas não interferiram sensorialmente nos atributos de aparência, cor, aroma e crocância. O salgadinho escolhido com 6% de substituição de grãos quebrados de arroz por cúrcuma em pó para cada 100 g, obteve 0,91 g de cinzas, 7,76 g de proteínas, 4,78 g de lipídeos, 5,84 g de fibra alimentar total, 86,94 g de carboidratos, 396,94 kcal, 174,75 mg compostos fenólicos totais e 6,52% de capacidade de sequestro de radicais DPPH. Quanto às farinhas pré-gelatinizadas, o processo de extrusão afetou as propriedades químicas da mistura, acarretando em uma diminuição da umidade, lipídeos, fibras, valor energético, compostos fenólicos totais e antocianinas, além da propriedade antioxidante. Os índices de absorção e solubilidade em água aumentaram após a extrusão, porém o índice de absorção de óleo não apresentou diferença significativa. A curva de DSC mostrou que a temperatura utilizada no processo foi suficiente para gelatinização do amido presente nas farinhas, não apresentando pico referente a esse parâmetro nas farinhas pré-gelatinizadas. As propriedades de pasta também foram afetadas pelo processo de extrusão obtendo farinhas pré-gelatinizadas com maiores viscosidade a frio e de pasta. Portanto, é possível incorporar polpa de açaí liofilizada e cúrcuma em pó aos grãos quebrados de arroz para produção de alimentos com alto valor nutricional, funcional e tecnológico.
32

Validação de metodologia para a quantificação de metanol em glicerina bruta utilizada na alimentação animal / Validation of methodology for quantifying methanol in crude glycerine used in animal nutrition

Carina Nazato 27 March 2015 (has links)
Estudos com a inclusão de glicerina bruta (GB) na alimentação animal vêm demonstrando benefícios quanto ao aporte energético conseguido, entretanto, existe uma variabilidade quanto aos teores de metanol encontrados na GB, nem sempre mensuradas, podendo apresentar riscos. Objetivou-se com este estudo: adaptar, otimizar e validar a metodologia oficial de determinação de metanol (MeOH) em biodiesel \"EN 14110\" para a matriz GB; aplicar o método para análise em amostras de glicerina bruta e avaliar o efeito do metanol na dieta de ruminantes por meio da técnica in vitro de produção de gases (PG). Foi utilizado um cromatógrafo gasoso Shimadzu modelo GC 2014 equipado com um detector de ionização de chamas (FID). Os parâmetros de validação foram linearidade, limite de detecção (LD) e quantificação (LQ), precisão, exatidão e efeito matriz. Foram analisadas duas amostras industriais de GB e uma obtida em laboratório por meio da reação de transesterificação do óleo de pinhão-manso (Jatropha curcas). A técnica semi automática de produção de gases foi utilizada para avaliar níveis crescentes de inclusão de MeOH na dieta via GB em substituição ao milho em grão a 0, 25, 50, 75 e 100%; correspondendo a doses de MeOH de 0, 0,018, 0,035, 0,053 e 0,071 mg, respectivamente. Como controle positivo foi adicionado um tratamento com inclusão de 8,3 mg MeOH puro na dieta controle sem inclusão de GB. As variáveis avaliadas foram produção de gases total (PGT), degradabilidade da matéria orgânica (DMO), eficiência na conversão de metano (CH4 effic) e o fator de partição (FP). As garrafas contendo as dietas foram incubadas a 39ºC por 24h. O método para análise de MeOH apresentou boa linearidade (r2 >= 0,99), e o LD e LQ foram 0,015 e 0,031%, respectivamente. Não foi observado efeito matriz significativo (4,36%). A precisão nas concentrações testadas, 0,05% e 0,5% foi de 2,09% e 2,39%, respectivamente. As concentrações de 0,05%, 0,2% e 0,5% (m/m) apresentaram recuperações de 88%, 95% e 91%, respectivamente. As amostras da indústria apresentaram teores de 0,047 e <LQ, enquanto que a obtida no laboratório apresentou 7,8% de metanol. A partir dos valores obtidos na produção de gases in vitro observou-se que a inclusão de GB contaminada com MeOH aumentou a DMO, PGT e CH4 e reduziu o FP. Conclui-se que o método é adequado para análise de MeOH em GB, com bom potencial para análise na matriz ração, quando otimizado. A GB contaminada com MeOH influencia a fermentação ruminal, sendo necessário mais estudos para elucidar os mecanismos envolvidos / Studies with the inclusion of crude glycerin (CG) in animal feed have demonstrated benefits on the energy intake achieved. However, there is a variation between the levels of methanol found in CG, not always analyzed, but often passed on to producers and may pose risks for using it as animal feed. The objective of this study was to optimize and to validate the official methodology \"EN 14110\" for determining methanol in biodiesel for CG matrix; to apply the method for analysis in commercial samples and samples produced in the laboratory; and to evaluate the effect of methanol in ruminant feed through the in vitro gas production technique (PG). It was used a Shimadzu gas chromatograph model 2014 GC equipped with a flame ionization detector (FID). The validation parameters were linearity, limit of detection (LOD) and quantification (LOQ), precision, accuracy and matrix effect. There were analyzed two industrial\'s samples and a sample obtained in the laboratory by transesterification of the oil from Jatropha curcas. The semi-automatic in vitro gas production technique was used to evaluate the use of MeOH inclusion in the ruminant diet via CG replacing corn grain at 0, 25, 50, 75 and 100%, corresponding to MeOH doses of 0, 0.018, 0.035, 0.053 and 0.071 mg respectively. As a positive control treatment was added with the inclusion of 8.3 mg pure MeOH. The variables evaluated were total gas production (GP), degradability of organic matter (DMO), efficiency in methane conversion (CH4 effic) and the partition factor (PF). The bottles containing the diets were incubated at 39 ° C for 24h. The method showed good linearity (r2 >= 0.99), the LOD and LOQ were 0.015 and 0.031%, respectively. There was no significant matrix effect (4.36%). The accuracy of the concentration tested, 0.05% e 0.5% was 2.09% and 2.39%, respectively. The concentrations 0.05%, 0,2% and 0.5% (w/w) showed recovery level of 88%, 95% e 91% respectively. The industry samples concentrations were 0.047 and <LOQ, while the laboratory one showed 7.8% of methanol. The in vitro gas production showed that the addition of CG increased GP, DMO and CH4 effc and reduced PF. It was concluded that the method is suitable for analysis in CG MeOH, with good potential for analysis of the feed array after optimization. CG contaminated with MeOH influence ruminal fermentation, requiring further studies to elucidate the mechanisms involved
33

Propriedades nutricionais, tecnológicas e sensoriais de farelo de arroz na elaboração de cookies / Nutritional, technological and sensory properties of rice bran in the preparation of cookies

Soares, Chaiane Goulart 31 August 2017 (has links)
Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-24T12:36:55Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Chaiane_Goulart_Soares.pdf: 1237252 bytes, checksum: c9ae7a978e1e4b365f2f95e1e936725f (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-24T13:56:21Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Chaiane_Goulart_Soares.pdf: 1237252 bytes, checksum: c9ae7a978e1e4b365f2f95e1e936725f (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-24T13:56:30Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Chaiane_Goulart_Soares.pdf: 1237252 bytes, checksum: c9ae7a978e1e4b365f2f95e1e936725f (MD5) / Made available in DSpace on 2018-05-24T13:56:30Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Chaiane_Goulart_Soares.pdf: 1237252 bytes, checksum: c9ae7a978e1e4b365f2f95e1e936725f (MD5) Previous issue date: 2017-08-31 / Sem bolsa / No processo de beneficiamento do arroz, é obtido como subproduto o farelo. A disponibilidade desse subproduto no Brasil é grande e sua utilização ocorre principalmente para a produção de ração animal, entretanto, grandes quantidades são desprezadas, pois o aproveitamento para consumo humano é incipiente e pouco diversificado. É caracterizado pelo seu alto valor nutricional, entretanto, o elevado conteúdo de lipídeos do farelo de arroz justifica sua pouca utilização em produtos alimentícios, devido sua instabilidade durante o armazenamento, podendo ser facilmente oxidado por enzimas causando ranço, mau cheiro, sabor amargo e tornando o alimento inadequado para consumo. Portanto, este subproduto deve passar por um processo de extração de óleo e estabilização para que possa ser introduzido na alimentação humana. O desenvolvimento de produtos enriquecidos nutricionalmente, sem glúten, com boas propriedades tecnológicas e sensoriais, possibilitando o reaproveitamento de subprodutos da indústria, se torna de grande importância para a comunidade científica, comércio e consumo geral. Dessa forma, objetivou-se, com o estudo, avaliar as propriedades nutricionais e tecnológicas do farelo de arroz desengordurado estabilizado e desenvolver biscoitos tipo cookies para avaliar suas características tecnológicas e sensoriais. Foi utilizado o farelo de arroz desengordurado estabilizado, onde foi avaliado sua composição proximal, capacidade antioxidante, acidez titulável, potencial hidrogeniônico (pH) e quantificação de vitamina C. Foram desenvolvidos biscoitos tipo cookies 100% farelo de arroz desengordurado com duas diferentes formulações, uma utilizando açúcar refinado e a outra com açúcar mascavo, para então realizar a análise sensorial dos cookies, a fim de verificar sua aceitação, preferência e intenção de compra. Verificou-se que o farelo de arroz desengordurado estabilizado, possui alto valor nutritivo, sendo fonte de proteína e fibra. A elaboração de biscoitos com boas características sensoriais e bom índice de aceitação a partir da substituição total do teor de farinha de trigo por farelo de arroz é possível, o que demonstra a viabilidade do emprego do farelo de arroz na produção de alimentos. / In the process of processing the rice, the bran is obtained as a by-product. The availability of this by-product in Brazil is great and its use in real time for the production of animal feed, however, large quantities are neglected, since the use for human consumption is incipient and little diversified. Is characterized by its high nutritional value, however, the high lipid content of rice bran justifies its low utilization in food products, due to its instability during storage, and can be easily oxidized by enzymes causing rancidity, bad smell, bitter taste and rendering, making the food unfit for consumption. Therefore, this by-product must undergo a process of oil extraction and stabilization so that it can be introduced into human food. The development of nutritionally enriched products, without gluten, with good technological and sensorial properties, allowing the reuse of by-products of the industry, becoming of great importance for the scientific community, commerce and general consumption. The objective of this study was to evaluate the properties and technology of stabilized defatted rice bran and to develop cookies to evaluate its technological and sensorial characteristics. The stabilized defatted rice bran was used, where its proximal composition, antioxidant capacity, titratable acidity, hydrogen ionic potential (pH) and quantification of vitamin C were evaluated. Cookies were developed with two different formulations, one using refined sugar and the other with brown sugar, to perform the sensorial analysis of cookies 100% defatted rice bran, in order to verify their acceptance, preference and purchase intention. It was verified that the defatted rice bran stabilized, has high nutritive value, being source of protein and fiber. The preparation of biscuits with good sensory characteristics and good acceptance rate from the total replacement of the wheat flour content by rice bran is possible, which demonstrates the feasibility of the use of rice bran in food production.
34

Inclusão de glicerina bruta em substituição parcial ao milho na dieta de ovinos / Inclusion of crude glycerin in partial replacement by corn in sheep diets

Daniel Montanher Polizel 17 January 2014 (has links)
Os efeitos do fornecimento de dietas contendo glicerina bruta foram avaliados em quatro experimentos com ovinos de diferentes categorias. Experimento 1: Quarenta cordeiros foram usados para avaliar os efeitos da inclusão de glicerina bruta sobre o desempenho, as características de carcaça e da carne e a concentração de enzimas hepáticas. As rações experimentais foram isonitrogenadas, sendo que o ajuste proteico foi realizado pela inclusão de ureia e farelo de soja. Os teores de inclusão de glicerina bruta foram: 0, 5, 10 ou 15% na MS. A adição de glicerina bruta causou efeito quadrático no CMS, CFDN, CPB, GMD e peso final. A inclusão de glicerina causou efeito quadrático para peso corporal ao abate, PCQ e PCF. Foi observado efeito quadrático para os ácidos graxos mirístico, palmítico, palmitoleico, linoleico e rumênico. A glicerina bruta demonstrou ser um bom substituto do milho em dietas com alto teor de concentrado, melhorando o desempenho e as características da carcaça dos animais quando incluída até 10% na MS. Experimento 2: Cinquenta cordeiros(as) foram usados para avaliar os efeitos da inclusão de glicerina bruta em rações com alta proporção de concentrado, sobre o desempenho, características de carcaça e parâmetros enzimáticos. As rações experimentais foram isonitrogenadas, sendo o ajuste proteico realizado pela inclusão de farelo de soja. Os teores de inclusão de glicerina bruta foram: 0, 5, 10, 15 e 20% na MS. A inclusão de glicerina bruta não afetou as variáveis de desempenho analisadas. Houve apenas efeito linear para o CMM. A glicerina bruta pode substituir o milho em até 20%, mantendo o desempenho dos animais e as características de carcaça. Experimento 3: Cinco borregos canulados no rúmen foram utilizados para avaliar os efeitos da glicerina bruta sobre os parâmetros ruminais, a digestibilidade das dietas e o metabolismo de nitrogênio. As dietas foram isonitrogenadas e os teores de inclusão de glicerina bruta foram: 0, 5, 10, 15 ou 20% na MS. Houve redução linear na ingestão de FDN e aumento linear na ingestão de MM. Houve efeito linear crescente para a digestibilidade da MS e MO. A inclusão de glicerina bruta causou redução linear no acetato, relação C2:C3, AGCC total, e aumento linear no pH ruminal. A glicerina bruta pode substituir até 20% do milho em dietas de borregos, melhorando a digestibilidade da MS e MO. Experimento 4: Cento e dezoito ovelhas com 90 dias de prenhez foram utilizadas para avaliar a inclusão de glicerina bruta em dietas de gestação e lactação. Os teores de inclusão foram 0 ou 10%. Da segunda a oitava semana foi mensurado o CMS e produção de leite das ovelhas e a ingestão de concentrado inicial dos cordeiros. A inclusão de glicerina bruta aumentou o CMM e reduziu a porcentagem de gordura no leite. A adição da glicerina bruta na dieta das ovelhas diminuiu a concentração sérica de AGNE. A inclusão de 10% de glicerina bruta na dieta de ovelhas durante a gestação e lactação não prejudica o desempenho dos animais e reduz a possibilidade de ocorrência de toxemia da gestação. / The effects of feeding diets with crude glycerin were evaluated in 4 trials using different categories of sheep. Experiment 1: Forty Santa Inês ram lambs were used to determine the effects of partial replacement of corn by crude glycerin on growth, hepatic enzymes, carcass and meat characteristics of lambs fed high-concentrate diets. The diets were isonitrogenous and the protein was adjusted by increasing urea and soybean meal. Increasing levels of crude glycerin were: 0, 5, 10 or 15%. There was quadratic effect for DMI, NDFI, CPI. ADG and final weight. There was a quadratic effect for slaughter BW and dressing percentage, but no difference on longissimus muscle area, backfat thickness and body wall thickness. There was quadratic effect for myristic, palmitic, palmitoleic, linoleic and rumenic acid. Crude glycerin is a good substitute of corn in high-concentrate diets, improving performance and carcass characteristics when included until 10% of the diet DM. Experiment 2: Fifty lambs were used to determine the effects of partial replacement of corn by crude glycerin on growth, carcass characteristics and hepatic enzymes of lambs fed high concentrate diets. The diets were isonitrogenous and the protein adjusted was performed with increased soybean meal. Increasing levels of crude glycerin were: 0, 5, 10, 15 or 20%. There was an increased in mineral matter intake. Crude glycerin can be used as a substitute for corn in high concentrate diets of ram lambs without affecting performance and carcass characteristics. Experiment 3: Five Santa Inês ram lambs, cannulated in the rumen, were used to determine the effects of using crude glycerin on ruminal constituents, diet digestibility and nitrogen metabolism. The diets were isonitrogenous and crude glycerin was included in the ration at 0%, 5%, 10%, 15% or 20% in the DM. There was linear decreased on NDF intake and a linear increase in ash intake. Feeding crude glycerin increased DM and OM digestibility. Crude glycerin decreased acetate, acetate:propionate ratio, total SCFA and showed a linear increase on pH. Replacing corn by crude glycerin up to 20% of dietary DM increased DM and OM digestibility, maintained propionate and decreased acetate and total SCFA. When soybean meal was used to adjust the diet protein level, there were no changes on nitrogen metabolism. Experiment 4: One hundred and eighteen 90 d pregnant ewes were used to determine the effects of feeding crude glycerin on performance, NEFA concentration and lamb growth. Diets were isonitrogenous and crude glycerin levels were zero or 10%. From the second until de eighth week of lactation DM intake of the ewes and starter of the lambs were measured. There was an increase on ash intake for the glycerin fed ewes. There was a decrease in milk fat percentage. Crude glycerin fed ewes showed a decrease on blood NEFA. The inclusion of 10% of crude glycerin in the diets of sheep during pregnancy and lactation had no detrimental effect on performance of ewes and lambs. Using 10% of crude glycerin decreases the chances of pregnancy toxemia in ewes.
35

Production of Renewable Fuels from Bio-Based Feedstocks: A Viable Path to Enhance Value Chain and Sustainability

January 2020 (has links)
abstract: The continued reliance on fossil fuel for energy resources has proven to be unsustainable, leading to depletion of world reserves and emission of greenhouse gases during their combustion. Therefore, research initiatives to develop potentially carbon-neutral biofuels were given the highest importance. Hydrothermal liquefaction (HTL, a thermochemical conversion process) of microalgae is recognized as a favorable and efficient technique to produce liquid biofuels from wet feedstocks. In this work, three different microalgae (Kirchneriella sp., Galdieria sulphuraria, Micractinium sp.) grown and harvested at Arizona State University were hydrothermally liquefied to optimize their process conditions under different temperatures (200-375 °C), residence times (15-60 min), solids loadings (10-20 wt.%), and process pressures (9-24 MPa). A one-factor-at-a-time approach was employed, and comprehensive experiments were conducted at 10 % solid loadings and a residence time of 30 min. Co-liquefaction of Salicornia bigelovii Torr. (SL), Swine manure (SM) with Cyanidioschyzon merolae (CM) was tested for the presence of synergy. A positive synergistic effect was observed during the co-liquefaction of biomasses, where the experimental yield (32.95 wt.%) of biocrude oil was higher than the expected value (29.23 wt.% ). Co-liquefaction also led to an increase in the energy content of the co-liquefied biocrude oil and a higher energy recovery rate ( 88.55 %). The HTL biocrude was measured for energy content, elemental, and chemical composition using GC-MS. HTL aqueous phase was analyzed for potential co-products by spectrophotometric techniques and is rich in soluble carbohydrates, dissolved ammoniacal nitrogen, and phosphates. HTL biochar was studied for its nutrient content (nitrogen and phosphorous) and viability of its recovery to cultivate algae without any inhibition using the nutrient leaching. HTL biochar was also studied to produce hydrogen via pyrolysis using a membrane reactor at 500 °C, 1 atm, for 24 h to produce 5.93 wt.% gas. The gaseous product contains 45.7 mol % H2, 44.05 ml % CH4, and 10.25 mol % of CO. The versatile applications of HTL biochar were proposed from a detailed physicochemical characterization. The metal impurities in the algae, bio-oil, and biochar were quantified by ICP-OES where algae and biochar contain a large proportion of phosphorous and magnesium. / Dissertation/Thesis / Doctoral Dissertation Chemical Engineering 2020
36

EXAMINATION OF MICRO-SCALE SULFIDE DISTRIBUTION FOR THE GOLD MINERALIZATION IN THE LAPPBERGET DEPOSIT, GARPENBERG MINE, SWEDEN: TOWARDS A GEOMETALLURGICAL APPROACH

Barbosa, Leo January 2021 (has links)
Ore characterization studies are of great importance to the mining industry, especially when dealing with precious metals by-products. It is a way towards increasing mining efficiency. The Swedish Boliden’s Zn–Pb–Ag–(Cu–Au) Lappberget Deposit is the main ore body at the Garpenberg Mine producing concentrates of zinc, lead, copper, and a gravity concentrate of silver and gold, which accounts for a significant revenue for the mine. Garpenberg Mine is an ancient and traditional mining site in Sweden, nonetheless the Lappberget deposit is a relatively recent discovery and there are still on-going studies on this ore body. More recently detailed ore investigations have been carried out on the sulfides and silver mineralization in different geological domains within the Lappberget deposit. In this context, the present work is focused on investigating the gold mineralization of the deposit, aiming to study the occurrence and distribution of gold minerals, characterize the gold in the ore and how its characteristics affect gold recoveries during its processing. To achieve these goals, different investigative methods were applied on drill core samples of the footwall disseminated to semi-massive mineralization (FWD), and on samples from the gravity concentrator at Boliden’s processing plant. The techniques applied were optical microscopy, scanning electron microscopy, energy dispersive x-ray spectrometry, electron probe microanalysis, laser ablation inductively couple plasma mass spectrometry, and bulk chemical analysis. The main findings pointed electrum as the main gold mineral, occurring with a strong sulfide association, in a variety of textures and grain sizes. The study also identified the occurrence of Au-Bi alloy, not previously described in literature of the Garpenberg region. The potential of invisible gold in the sulfide carriers was also a subject of investigation, as well as the evaluation of the characteristics of the samples from the gravity concentrator.
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Syntéza aluminátosilikátových systémů na bázi geopolymerů orientovaná na využívání sekundárních surovin / Synthesis of Aluminosilicate Systems Based on Alkali Activation of Industrial By-Products

Kalina, Lukáš January 2011 (has links)
Portland cement-based products are the most commonly used building materials. However, it is well known that the production of OPC not only consumes a significant amount of natural resources and energy but also releases high quantity of carbon dioxide (CO2) to the atmosphere. Purpose of this work is to develop new cementitious material similar to Portland cement-based concrete, which is convenient in terms of energy and is environmental-friendly at once. This work presents preparation, composition and properties of inorganic aluminosilicate polymer, called geopolymer, synthesized from blast furnace slag and fly ash, activated by sodium hydroxide and cement kiln dust. Study of the microstructure was based on SEM-EDX-WDX, TG-DTA-EGA and XRD analysis.
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Studies on Utilization of Tamarind Kernel Powder Extract Residue as a Feed for Ruminants / タマリンド核抽出粕の反芻家畜用飼料としての利用に関する研究

Lin, Wang 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20434号 / 農博第2219号 / 新制||農||1049(附属図書館) / 学位論文||H29||N5055(農学部図書室) / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 廣岡 博之, 教授 松井 徹, 教授 久米 新一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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Studies on utilization of by-products for ruminant feeds in tropical Asia / 熱帯アジアにおける未利用資源の反芻家畜への飼料化に関する研究

Sakai, Takashi 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20446号 / 農博第2231号 / 新制||農||1050(附属図書館) / 学位論文||H29||N5067(農学部図書室) / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 廣岡 博之, 教授 松井 徹, 教授 久米 新一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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A Non-Biological Inhibition Based Sensing Technique (NIBS) for the Detection of Halogenated Disinfection By-Products in Water

Afreh, Isaac K. 21 May 2013 (has links)
No description available.

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