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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.
751

Efeito do armazenamento na qualidade dos grãos e do óleo de crambe, para produção de biodiesel

Bezerra, Pedro Henrique Silva [UNESP] 07 March 2014 (has links) (PDF)
Made available in DSpace on 2014-08-13T14:51:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-07Bitstream added on 2014-08-13T17:59:35Z : No. of bitstreams: 1 000776590.pdf: 1414314 bytes, checksum: add08196a1b197bce01adf81467903aa (MD5) / O crambe, devido a sua riqueza em óleo vegetal é uma ótima opção para a produção de biodiesel. O armazenamento é prática fundamental para a qualidade fisiológica do grão. As embalagens utilizadas devem ajudar a diminuir a velocidade do processo de deterioração, mantendo a qualidade do grão. Diferentes combinações de práticas de manejo e condições ambientais afetam a capacidade de armazenamento de grãos em silo bolsa e sacaria, proporcionando maior preservação da matéria prima para a extração do óleo. Dessa maneira, o presente trabalho tem como objetivos avaliar a qualidade do grão e do óleo de crambe submetido a diferentes condições de armazenamento, visando à produção de biodiesel. O delineamento experimental foi inteiramente casualizado, fatorial triplo, com dois tipos de embalagens, três condições de ambiente e três períodos de armazenamento e com três repetições. As análises de qualidade dos grãos foram teor de água, acidez graxa, condutividade elétrica, cor e rendimento de óleo. As análises de qualidade do óleo foram: índice de iodo, viscosidade, massa específica, índice de acidez e teor de água. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de “t” à 5% de probabilidade. Os resultados apontam que a embalagem hermética resistiu às influências do armazenamento e manteve a qualidade dos grãos e do óleo, o tempo de 12 meses apresentou níveis inseguros de qualidade e o ambiente câmara climatizada apresentou evidencias de deterioração em todos os quesitos avaliativos, nas embalagens e bolsa hermética e sacaria convencional. / The crambe, due to its richness in vegetable oil is a great option for the production of biodiesel. Storage is essential for the physiological quality of the grain practice. Packaging used should help slow the process of deterioration, maintaining grain quality. Different combinations of management practices and environmental conditions affect the ability of grain storage silo bag and sacks, providing greater preservation of raw material for the extraction of oil. Thus, this study aims to evaluate the quality of grain and crambe oil under different storage conditions, aiming at the production of biodiesel. The experimental design was completely randomized, triple factorial, with two types of packaging, three environmental conditions and three storage periods, with three replications. Analysis of grain quality were water content, fat acidity, electrical conductivity, color and oil yield. The analysis of oil quality were: iodine value, viscosity, density, acid value and water content. The results were subjected to analysis of variance and means were compared by the t test at 5% probability. The results show that the hermetic packaging resisted the influences of storage and kept the quality of grain and oil, the time 12 months had unsafe levels of quality and climatic chamber environment showed evidence of deterioration in all evaluative questions, packaging and bag and conventional hermetic sacks.
752

Produção de ligno-hemi-celulases por fermentação em estado sólido e avaliação dos efeitos da aplicação das enzimas na composição química e estrutura do bagaço e da palha de cana

Moretti, Marcia Maria de Souza [UNESP] 22 November 2013 (has links) (PDF)
Made available in DSpace on 2014-12-02T11:16:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-11-22Bitstream added on 2014-12-02T11:21:22Z : No. of bitstreams: 1 000794674_20151122.pdf: 159305 bytes, checksum: 1a69d7746b9537ef5de8785498d29618 (MD5) Bitstreams deleted on 2015-11-27T16:09:58Z: 000794674_20151122.pdf,. Added 1 bitstream(s) on 2015-11-27T16:10:42Z : No. of bitstreams: 1 000794674.pdf: 2802997 bytes, checksum: 3381bd1473d6cc3c5215e1c2590cb7b4 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / No presente estudo, o fungo termofílico Myceliophthora thermophila M.7.7, foi cultivado em fermentação em estado sólido (FES), usando como fonte de carbono misturas de bagaço de cana, palha de cana e palha de milho, com farelo de trigo (w/w 1:1). As fontes de nutrientes minerais avaliadas foram substâncias químicas analíticas e fertilizantes agrícolas. Os efeitos das condições de fermentação, tais como temperatura, pH e umidade sobre a produção de xilanase, endoglucanase e β-glucosidase foram estudados. Além disso, foi realizado o prétratamento do bagaço e da palha de cana submetidos a 2 min de irradiação em micro-ondas com glicerol 70% em solução ácida, alcalina e água destilada. As frações sólidas resultantes do pré-tratamento foram utilizadas nas análises de fibras, TGA, DTG, DSC, FTIR e microscopia eletrônica de transmissão e as frações líquidas, para análises de açúcares e fenóis. Amostras de bagaço e de palha tratados e não tratados (controle) foram submetidas à hidrólise enzimática por 24 e 72 horas, a 55 °C, usando as soluções enzimáticas obtidas do cultivo de M. thermophila M.7.7. e comercial (Celluloclast 1.5L) com atividade de endoglucanase padronizadas a 60 U/g de substrato seco ou com relação à quantidade total de proteínas das soluções (5 mg/g de substrato seco). Ao extrato de M. thermophila M.7.7 foi feita uma suplementação com enzima β-glicosidase comercial, de modo a atingir a mesma atividade presente na enzima Celluloclast. As atividades máximas de xilanase (446,9 U/mL), endoglucanase (94,7 U/mL) e β-glicosidase (2,8 U/mL) foram obtidas no cultivo por FES com 70% de umidade, a 40 ºC, usando palha de milho e farelo de trigo e solução nutriente composta por fertilizantes agrícolas, com pH ajustado para 5,0. Os espectros de infravermelho e as análises térmicas mostraram que o prétratamento agiu principalmente sobre a lignina e a hemicelulose do bagaço de cana, ... / This study investigated the effect of non expensive carbon and nitrogen sources on enzyme production by Myceliophthora thermophila M.7.7 in solid-state fermentation. Three kinds of lignocellulosic waste (corn straw, sugarcane bagasse and sugarcane straw) and six nitrogen sources (urea, calcium nitrate, analytical ammonium sulphate, yeast extract, agricultural fertilizer NPK 20-05-20 and fertilizing grade ammonium sulphate) were tested. Some physical-chemical parameters of the fermentation, such as temperature, initial pH and moisture content of the substrate on enzyme production were evaluated. Furthermore, the pre-treatment of bagasse and sugar cane straw with microwave radiation in presence of glycerol diluted in water, sulphuric acid and sodium hydroxide on the chemical composition, fiber structure and the efficiency of subsequent enzymatic hydrolysis was investigated. Bagasse and cane straw were subjected to 2 min of irradiation and the solid fractions resulting were used in the analysis of fibers, TGA, DTG, DSC, FTIR, X-ray and transmission electron microscopy and liquid fractions used to detemine sugar and phenol contents. Samples of bagasse, treated cane straw and untreated cane straw (control) were submitted to enzyme hydrolysis for 24 to 72 h at 55 °C with enzymatic solutions obtained by the cultivation of M. thermophila M.7.7. and Celluloclast 1.5L based on 60 U of endoglucanase activity per g of dry substrate or on the total amount of protein solutions (5 mg protein/g of dry substrate). The enzyme solution from M. thermophila M.7.7 was supplemented with a commercial β-glucosidase in order to achieve the same activity present in Celluclast. The maximum xylanase activity (446.9 U/ml), endoglucanase (94.7 U/ml) and β-glucosidase (2.8 U/mL) were obtained in the cultivation by SSF with 70% humidity, 40 °C using corn stover and wheat bran and nutrient solution composed of agricultural fertilizers, with pH adjusted to 5.0. ...
753

Aggregated understanding of characteristics of wheat straw node and internode with their interfacial bonding mechanisms

Ghaffar, Seyed Hamidreza January 2016 (has links)
The demand for the efficient utilisation of straw biomass requires detailed analyses of its fundamental chemical structures, morphological complexity, individual cell wall components and the correlation of physicochemical to mechanical properties. The study involved two main areas: understanding the details of microstructure and characterisation/differentiation of properties of various profiled wheat straw. Comprehensive and systematic experimental programmes were therefore designed in order to thoroughly investigate the node and internode of wheat straw with quantitative appraisals and qualitative interpretations. This could contribute towards its valorisation in bio-refinery pathways. The sophisticated morphology of node and internode, inner and outer surface was investigated. It was found that the morphology across node area has a great variety when the longitudinal profile is investigated in the upwards direction to grain head. A 3D image of nodes illustrated the dense core with elliptical shaped rings organised in order to provide the echanical strength to the overall stem. The variation of cell wall composition across wheat straw node and internode showed that node yielded slightly higher Klason lignin, extractives and ash content than internode, which could be related to their morphology, precisely the higher ash and extractives content in the node are explained by thicker epidermis tissue. The physicochemical and mechanical properties of node and internode were differentiated and the effects of a combination of mild physical pre-treatment were monitored. The results indicated: i) the reduction of waxes from the outer surface, ii) significantly lower (P < 0.05) extractives and iii) the dissolution of silicon (Si weight %) on the outer surface of node and internode. The tensile strength of nodes and internodes after pre-treatments also resulted in a significant increase (P < 0.05). The accumulated characteristic data enabled the investigation of interfacial properties and bonding mechanisms of the inner and outer surface of wheat straw with thermosetting resins. Different surface functionalities and anatomical sections, altered the bonding performance, i.e. waxes and silica concentrated on the outer surface inhibited the quality of the interface. Nevertheless, the treatment improved interface (P < 0.05) between resins and the micro-porous surface of wheat straw by causing the microcellular structure of straw to expand and hence inspire the mechanical entanglement on a micro level upon resin solidification.
754

Predicting the ecosystem effects of harvesting beach-cast kelp for biofuel

Orr, Kyla Kathleen January 2013 (has links)
Beach‐cast kelp (principally Laminaria spp.), known as macroalgal wrack, has been suggested as a feedstock for biofuel. However, to be extracted sustainably it is necessary to understand its ecological role and predict the impacts of its removal. Field‐based observations combined with food web modelling were used to predict the ecosystem effects of removing wrack from beaches of the Uists, western Scotland. Beaches with wrack were associated with enriched benthic infauna (polychaetes) on the lower shore, and wrack mounds supported abundant macroinvertebrates (mainly Diptera larvae and oligochaetes); with some of the highest biomasses reported globally for beaches. These fauna are valuable prey to shorebirds, as demonstrated by a strong positive relationship (R2 = 0.82) between wader abundances and the percentage cover of wrack on beaches. Inshore, drifting macroalgae was associated with elevated abundances of detritivorous hyperbenthic fauna (mysids, isopods and gammarid amphipods). In addition, the volume of drifting macroalgae inshore was a significant predictor (along with physical beach characteristics) for the abundance of decapods and fish. Food web models and network analysis indicated that beaches which accumulate wrack had a greater diversity of trophic links and more functional redundancy, making their food webs more resilient to perturbations. Such perturbations may include stressors induced by climate change, such as increased erosion of sediments during storms, elevated atmospheric and sea surface temperatures and elevated CO2 concentrations. Model simulations of wrack harvesting predicted an immediate decline in primary consumers in direct proportion to the quantity of wrack removed, and a slow decline in shorebirds in response to reduced prey. Primary consumers were predicted to recover to their pre‐harvest biomasses within 1 to 2 years regardless of harvesting intensity, but recovery times for shorebirds were an order of magnitude longer, and increased with harvesting intensity. Harvesting more than 50% wrack predicted a ‘collapse’ in wader populations within 25 years, and recovery times of 45‐60 years were estimated if >70% wrack was removed. The findings of this thesis suggest wrack provides essential food and shelter to coastal fauna, and its large‐scale removal would have significant negative impacts to the ecosystem functioning.
755

Study on biomass in semiaquatic insects (Odonata) over a 20-year period in central, Sweden.

Zsoldos, Andreas January 2018 (has links)
This study is about how biomass of dragonflies insects have changed over the past 20-years in a forested area of central Sweden. This was done by analysing previously collected Odonata larvae stored in ethanol where sampling effort corrects the weight per locality. The results display a small but significant biomass increase over past decades, going against the recently observed trend of biomass decline in insects. However, this biomass gain was not even between the families, the ones that increased the most was Aesnidae and Libelluidae.  The reasons for the observed increase are discussed, some possible suggestions are less disturbance in their environments and their ability to adapt due to their long evolution giving them a phenotypical advantage.
756

Production of butyric acid by the cellulolytic actinobacterium Thermobifida fusca

Merklein, Kyle January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Mei He / Thermobifida fusca, an aerobic moderately thermophilic, filamentous soil bacterium is capable of producing butyric acid. Butyric acid is a 4-carbon short chain fatty acid that is widely used in the chemical, food, and pharmaceutical industries. Currently, butyric acid is primarily produced through petroleum-based chemical synthesis, but could be a candidate to be produced by fermentation. By producing through a fermentation platform, production of butyric acid can be shifted from a non-renewable to a renewable source. In an effort to make T. fusca produce a high yield of butyric acid, multiple fermentation parameters were explored and optimized. The effect of different carbon sources (mannose, xylose, lactose, cellobiose, glucose, sucrose, and acetates) on butyric acid production was studied, where cellobiose produced the highest yield of 0.67 g/g C (g-butyric acid/g-carbon input). The best stir speed and aeration rate for butyric acid production were found to be 400 rpm and 2 vvm in a 5-L fermentor. The maximum titer of 2.1 g/L butyric acid was achieved on 9.66 g/L cellulose. Fermentation was performed on ground corn stover as a substrate to evaluate the production of butyric acid on lignocellulosic biomass, and the optimized conditions resulted in a titer of 2.37 g/L butyric acid. The butyric acid synthesis pathway was identified involving five genes that catalyzed reactions from acetyl-CoA to butanyol-CoA in T. fusca. A study into the transcriptomics of T. fusca was begun by growing T. fusca under a variety of fermentation conditions, isolating the messenger RNA, and performing a sequence of the mRNA using whole transcriptome shotgun sequencing. The results of sequencing of various samples were plotted to determine correlation across numerous fermentation parameters. This correlation based analysis determined that the carbon to nitrogen ratio has the largest overall impact on gene transcription of T. fusca among all of the fermentation parameters studied. Overall, the work from this study proves that production of butyric acid is possible from a renewable cellulosic feedstock.
757

Sinteses e caracterização de zeólitas para imobilização da lipase de Thermomyces lanuginous aplicada a produção de biodiesel a partir de óleo de palma via rota etílica

Luizon Filho, Roberto Antonio [UNESP] 23 November 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-11-23Bitstream added on 2014-06-13T20:56:19Z : No. of bitstreams: 1 luizonfilho_ra_me_sjrp.pdf: 2226610 bytes, checksum: 7ef836fc66e512e96ee4f8432117e475 (MD5) / O termo zeólitas abrange a classe dos alumino silicatos hidratados de metais alcalinos ou alcalino-terrosos. A enzima lipase de Thermomyces lanuginosus foi imobilizada em zeolitas, produzindo um catalisador heterogêneo com potencial aplicação para a produção de biodiesel. Dois tipos de zeolita foram sintetizados: zeolita gismondina (GIS/Na) e um novo material zeolitico com topologia faujasítica (FAU/Co e FAU/Cu). A zeolita gismondina foi submetida ao processo de troca iônica com os cátions divalentes Ni 2+ , Co 2+ , Mg 2+ , Sr 2+ , Mn 2+ e Ca 2+ (GIS/Ni, GIS/Co, GIS/Mg, GIS/Sr, GIS/Mn e GIS/Ca) e a zeólita com topologia faujasítica foi submetida ao processo de troca iônica com NH4 + (FAU/Co.NH 4 e FAU/Cu.NH 4 ) e posteriormente calcinada a 500 o C (FAU/Co.H + e FAU/Cu.H + ). Estes materiais foram utilizados como suporte sólido para a imobilização enzimática, dando origem aos complexos zeolita-enzima: GIS/Ni/ENZ, GIS/Co/ENZ e FAU/Co.NH 4 /ENZ por exemplo. Foram utilizados dois métodos diferentes de imobilização. Em um deles, foi feito um pré-tratamento da lipase com o substrato (óleo de soja) e em outro a enzima foi imobilizada sem o pré-tratamento com o substrato. Foram feitos experimentos de transesterificação de triglicerídeos para a produção de biodiesel utilizando como catalisador da reação as zeolitas puras, a enzima pura e os complexos zeolita-enzima. Os catalisadores com topologia faujasitica (FAU/Co e FAU/Cu) atuando em condições experimentais de 100 o C, razão molar óleo:álcool de 1:50 por 12 horas fornecem bons rendimentos de ésteres (90%). Os catalisadores GIS/Ni/ENZ e FAU/Co.NH 4 /ENZ (imobilização com pré tratamento da enzima) apresentaram os maiores valores de atividade enzimática e bons rendimentos de ésteres etílicos. A mesma quantidade de enzima (0,4 mg) foi utilizada em sua forma livre e imobilizada... / The term zeolites comprehend the class of hydrated alkaline or earth alkaline metals alumino silicates. Thermomyces lanuginosus lipase enzyme was immobilized on zeolites, producing a heterogeneous catalyst with potential application on biodiesel production. Two types of zeolite were synthesized: gismondina zeolite (GIS/Na) and a new faujasite like zeolitic material: (FAU/Co e FAU/Cu). Gismondine zeolite was ion exchanged with divalent cations Ni 2+ , Co 2+ , Mg 2+ , Sr 2+ , Mn 2+ e Ca 2+ (GIS/Ni, GIS/Co, GIS/Mg, GIS/Sr, GIS/Mn e GIS/Ca) and the faujasite like zeolite was ion exchanged with NH4 + (FAU/Co.NH 4 e FAU/Cu.NH 4 ) and after this it was calcined at 500 o C (FAU/Co.H + e FAU/Cu.H + ). These materials were used as solid support for enzymatic immobilization originating the zeolite-enzyme complexes: GIS/Ni/ENZ, GIS/Co/ENZ and FAU/Co.NH 4 /ENZ for example. Two different methods of immobilization were used. In one of them the lipase was pretreated with the substrate (soybean oil) and in the other one the enzyme was immobilized without the pretreatment with substrate. Triglycerides transesterification experiments to biodiesel production were carried out using pure zeolite, pure enzyme and the zeolite-enzyme complexes as reaction catalyst. When used with experimental conditions of 100 o C, oil:alcohol molar ratio of 1:50 faujasite like catalyst performed good ester yield (90%). GIS/Ni/ENZ and FAU/Co.NH4 /ENZ catalysts (immobilization with pretreated enzyme) showed higher enzymatic activity values and good ethylic esters yield. The same amount of enzyme (0,4 mg) was used in its free and immobilized form in the transesterification reaction (45 o C, oil:alcohol molar ratio of 1:5 for 48 hours). Comparing transesterification reaction esters yield for the free enzyme (51,9%) and for the GIS/Ni/ENZ (70,3%) and FAU/Co.NH4 /ENZ (58,4%) catalysts, was possible... (Complete abstract click electronic access below)
758

Desempenho operacional e opacidade da fumaça do trator agrícola em função do tipo de biodiesel (soja x murumuru) em operação de preparo do solo

Neves, Murilo Coelho Theodoro [UNESP] 12 July 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-12Bitstream added on 2014-06-13T20:30:04Z : No. of bitstreams: 1 neves_mct_me_jabo.pdf: 649825 bytes, checksum: b1b6343dc2ae70fc1e2bf8456113a94c (MD5) / Biodiesel é um combustível obtido por meio da transesterificação de óleos vegetais e gorduras animais, possui caráter renovável e biodegradável. Em crescente uso, faz-se necessário ampliar as matérias primas disponíveis em várias regiões e estudar o efeito destas novas fontes na maquinaria agrícola. Objetivou-se com o presente trabalho comparar biodiesel de soja com biodiesel de murumuru. Para tanto, avaliou-se desempenho operacional e opacidade da fumaça do trator agrícola. O experimento foi realizado no Departamento de Engenharia Rural, da UNESP/Jaboticabal. As proporções de mistura biodiesel/diesel foram: B0 (0% de biodiesel e 100% de diesel), B5 (5% de biodiesel e 95% de diesel), B15 (15% de biodiesel e 85% de diesel), B25 (25% de biodiesel e 75% de diesel), B50 (50% de biodiesel e 50% de diesel), B75 (75% de biodiesel e 25% de diesel) e B100 (100% de biodiesel e 0% de diesel). Os resultados evidenciaram aumento de 15,85 e 9,59% no consumo específico de combustível comparando B0 a B100 de soja e de murumuru, respectivamente. A opacidade da fumaça reduziu 26,10% e 53,54 quando se trabalhou com biodiesel de soja e murumuru, respectivamente. A opacidade de B100 de murumuru foi 19,81% menor que B100 de soja / Biodiesel is a fuel obtained by transesterification of vegetable oils and animal fats, has renewable and biodegradable character. In growing use, it is necessary to expand the raw materials available in various regions and to study the effect of these new sources in agricultural machinery. The objective of this work was to compare soybean biodiesel and murumuru. For this, was evaluated the operational performance and smoke opacity of the tractor. The experiment was conducted at the Department of Rural Engineering, UNESP/Jaboticabal. The mixing ratios of biodiesel/diesel were B0 (0% of biodiesel and 100% of diesel), B5 (5% of biodiesel and 95% of diesel), B15 (15% of biodiesel and 85% of diesel), B25 (25% of biodiesel and 75% of diesel), B50 (50% of biodiesel and 50% of diesel), B75 (75% of biodiesel and 25% of diesel) and B100 (100% of biodiesel and 0% of diesel). The results showed an increase of 15,85% and 9,59% in specific fuel consumption compared B0 to B100 of soybean and murumuru, respectively. The opacity of the smoke decreased 26,10% and 53,54%when working with biodiesel of soybean and murumuru, respectively. The opacity of B100 of murumuru was 19.81% less than B100 of soybean
759

Qualidade de cavacos produzidos em sistemas florestais de curta rotação de eucalipto para fins energéticos

Ceragioli, Natalia Sousa [UNESP] 06 August 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-06Bitstream added on 2014-06-13T19:31:37Z : No. of bitstreams: 1 000756934.pdf: 1452179 bytes, checksum: 821c01bc2b142723fd36a737540c3fc0 (MD5) / Este estudo teve como objetivo avaliar densidade de carga da produção de cavacos em função da granulometria de dois sistemas florestais de curta rotação de Eucalyptus urograndis. Um ensaio foi realizado em Botucatu- SP, o plantio da área em ocorreu em julho 2010, com espaçamento de 2,8 x 1,5 m, e com 30 meses a área foi colhida, com a utilização de uma carreta com células de carga e com volume conhecido e foi realizada pesagens para seis dimensões de cavacos (5 mm, 10 mm, 15 mm, 20 mm, 25 mm e 33 mm) tendo três repetições para cada, para poder determinar a densidade de carga. Em janeiro de 2010, foi implantado em Taiobeiras- MG, o outro ensaio, com os diferentes clones (I-144, I-224, I-042 e I-60) no espaçamento de 4,0 x 0,5 m com a finalidade de produção de bioenergia na forma cavacos de 33 mm. A colheita foi realizada com 37 meses, com uma carreta de volume conhecido e uma balança rodoviária para determinar a densidade de carga. Para os dois ensaios foi utilizado o mesmo sistema mecanizado específico para produção de cavaco. Os resultados foram analisados pela análise de variância e, posteriormente, teste de Tukey. Concluindo que quanto maior dimensão dos cavacos menor a densidade de carga e que numa mesma situação para diferentes clones da mesma espécie de eucalipto se encontra diferentes valores de densidade de carga / This study aimed to evaluate the bulk density of a wood chip production as a function of particle size of two short forestry rotation system of Eucalyptus urograndis. One trial was conducted in Botucatu-SP, the planting area occurred in July 2010, with spacing of 2.8 x 1.5 m, and within 30 months the area was harvested with the use of a trailer with load cells and known volume, and was weighing carried out for six dimensions chip (5 mm, 10 mm, 15 mm, 20 mm, 25 mm and 33 mm) with three replicates for each, in order to determine the bulk density. In January 2010, it was deployed in Taiobeiras-MG, the second test, with different clones (I-144, I-224, I-042 and I-60) at a spacing of 4.0 x 0.5 m with purpose of bioenergy production in 3 the form of 33 mm wood chips. The harvest was performed 37 months, with a cartload of known volume and scale road to determine the bulk density. For both tests the same specific mechanical system was used to produce chip. The results were analyzed by analysis of variance and then the Tukey test. In conclusion that the larger dimension of the wood chips minus the bulk density and in the same situation for different clones of the same species of eucalyptus is different values of bulk density.
760

Efeito do sistema de secagem de crambe (Crambe abyssinica Hochst) na qualidade dos grãos e do óleo para produção de biodiesel

Silva, Magnun Antonio Penariol da [UNESP] 01 March 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-03-01Bitstream added on 2014-06-13T19:11:23Z : No. of bitstreams: 1 silva_map_me_botfca.pdf: 1245914 bytes, checksum: a5cbb6666f0b54b7a5b08e5a833b0de1 (MD5) / O crambe (Crambe abyssinica Hochst) é uma planta oleaginosa promissora para produção de biodiesel, por apresentar elevado teor de óleo em seus grãos. É uma cultura de cultivo totalmente mecanizado, de ciclo relativamente curto, e é uma ótima opção para safrinha por se tratar de uma cultura de inverno. O método de secagem de grãos pode influenciar o rendimento e a qualidade do óleo extraído dos grãos. Dessa maneira o presente trabalho teve por objetivo avaliar a qualidade dos grãos e óleo de crambe submetidos a diferentes sistemas de secagem. O delineamento utilizado foi inteiramente utilizado com quatro repetições. Os tratamentos consistiram em testar cinco métodos de secagem (secagem artificial com ar aquecido, secagem artificial com ar não aquecido, secagem em terreiro, secagem em campo e secagem à sombra). As análises de qualidade dos grãos realizadas foram acidez graxa, condutividade elétrica, porcentagem de grãos verdes, teor de clorofila a e b e rendimento de óleo. A extração do óleo foi realizada por prensa mecânica e para verificar a sua qualidade foram realizadas as análises de índice de iodo, viscosidade, massa específica, índice de acidez e teor de água, posteriormente foi realizado a caracterização do biodiesel. Após obtenção dos resultados, os dados foram submetidos à análise de variância, e quando significativo, as médias foram comparadas pelo teste “t” a 5% de significância. Pelos resultados obtidos, foi observado superioridade do sistema de secagem na planta na qualidade dos grãos, os métodos de secagem influenciaram o rendimento do óleo, no entanto não afetaram significativamente sua qualidade / The crambe (Crambe abyssinica Hochst) is a promising oilseed plant for biodiesel production, by having high oil content in its grain. It is a culture of fully mechanized cultivation, relatively short cycle, and is a great choice for off-season because it is a winter crop. The method of drying grain may influence the yield and quality of the extracted oil of the grains. Thus the present study aimed to assess the quality of grain and oil crambe submitted to different drying systems. The design was fully utilized with four replications. Treatments consisted of five test drying methods (artificial drying with heated air, artificial drying with unheated air, drying yard, field drying and shade drying). The analyzes were performed grain quality fat acidity, electrical conductivity, percentage of green beans, chlorophyll a and b and oil yield. The oil extraction was performed by mechanical press and to verify the quality of the analyzes were performed iodine index, viscosity, density, acid number and water content, further characterization was performed biodiesel. After obtaining the results, the data were subjected to analysis of variance, and when significant, the means were compared by t test at 5% significance. From the results, it was observed superiority of the drying system in the plant on grain quality, drying methods influence the yield of oil, but did not significantly affect their quality

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