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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.
251

Optimization of Pre-hydrolysis Conditions for the Production of Biogas

Awasume, Ignatius Ekwe, Sathiyaraj, Abel Prince Jabakumar January 2012 (has links)
Hydrolysis and solubilisation of organic material is known to be the rate limiting step during anaerobic digestion. In this study, the effect of pre-hydrolysis was investigated. The substrate had a composition of the following wastes streams: fish and slaughterhouse waste, cleaning waste, doggy meat, doggy sludge, doggy dry food, mink (fur), Norway slurry, SOR2-Industrial waste, and municipal solid waste (MSW) from households in Borås community.Analyses were made on two batches of experiments performed at two different mesophilic temperature conditions; 34 0C and 42 0C and with or without the addition of mesophilic sludge obtained from a waste water treatment plant. One of the substrate maintained the original carbon/nitrogen (C/N) ratio, and for the other substrate the carbon nitrogen ratio was then slightly increased by adding 7.98g of special shredded paper which contains 82% volatile solids (VS). The experiments were run for 7days with samples collected regularly after 0 day, 4 days, 5 days, 6 days and 7 days retention time. Chemical oxygen demand (COD), pH, total nitrogen, and volatile fatty acids (VFAs) as process indicators were analyzed.The results showed that at 42 0C the rate of hydrolysis was faster with a higher COD release and removal. The optimum retention time for hydrolysis was 4 days and any longer time caused some of the carbon to be lost to carbon dioxide. The effect of adding mesophilic sludge had no significant effect. An increased C/N ratio resulted in a balanced system with lower VFAs produced compared with that from the original substrate mixture. / <p>Acknowledgements: The authors are heartily thankful to their supervisor Ilona Sárvári Horváth whose guidance and support from the initial to the final level of this thesis work enabled us to gain a deeper understanding of the project.</p><p>We equally extend our sincere gratitude to the following persons who never ceased in helping until this work was complete.</p><p>Solmaz Aslanzadeh: For sharing her precious time and positive insight in coping with associated challenges of the project.</p><p>Hanson Jonas: Your assistance and patience over our laboratory experiments given the limited resources vis-a-vis students demand is quite reminding and saluted.</p><p>The support team at Sobacken Biogas plant: Your concern and timely assistance beginning from the supply of the substrate and the opportunity granted us to use your laboratory station greatly ensured results validation.</p><p>Program: MSc in Resource Recovery - Sustainable Engineering</p><p>Program: MSc in Resource Recovery - Industrial Biotechnology</p>
252

Investigations on the nitrogen inhibition during an anaerobic co-digestion process

Ravikumar Gopinath, Mitta Mohana, Kumar Gopalam, Kiran January 2011 (has links)
Nitrogen Inhibition during an anaerobic co-digestion process was studied in this work.The substrate and inoculum used were obtained from a thermophilic biogas plant Sobacken,situated in Borås, Sweden. The batch experiments have been carried out in triplicate reactorswith different concentrations of ammonia ranging from 2400mg/l to 3400mg/l. The batchexperiment was working well for the all the concentrations of ammonia investigated. Theaverage methane yield was around 0.65 Nm3 CH4/kgVS for all the reactors. The laboratorywork has been further proceeded with a continuous process having two reactors working inparallel. Reactor 1 containing only substrate and the Reactor 2 contain substrate with surplusammonia added to make final concentration of 3400mg/l. The reactors were operated atorganic loading rate (OLR) of 3.3gVS/l/day and hydraulic retention time (HRT) of 20 days.Both reactors worked well for 29 days. During a period of an initial stable operation, theaverage methane production of Reactor 1 was 0.59 Nm3CH4/kgVS/day and for Reactor 2 theproduction rate was 0.56 Nm3CH4/kgVS/day. Then Reactor 1 showed a steady decrease in pHand methane production, while Reactor 2 showed stable operation for a few days longer withdecreasing pH and methane production only from day 36. The composition of substrate wasnot optimal; therefore the inhibition level of ammonium could not be determined.
253

Land reclamation by reindeer lichens : On the complexity of substrate and reindeer grazing on Cladonia spp. dispersal

Godeau, Christine January 2019 (has links)
Reindeer lichens are on a dramatic decline in Sweden, with a 71 % decrease in abundance over the last 60 years. Reindeer (Rangifer tarandus tarandus L.) management, undertaken by indigenous Sámi people, depend upon extensive winter grazing grounds with abundant reindeer lichen cover. The objective of this pilot study is to restore the ecosystem function of reindeer winter grazing in post-industrial environments, by developing an artificial dispersal program of reindeer lichen thalli. This study is performed in co-operation with the mining corp. of LKAB and in consultation with Laevas reindeer herding district. There are two components to this study: I) a comprehensive literature review of indigenous and scientific knowledge regarding reindeer winter grazing and artificial reindeer lichen dispersal; and II) a field assessment of relationships between fructiose lichen occurrence and environmental variables within a coarse grid overlapped on a mosaic of vegetation patches in various successional stages, which cover part of a 28-year old abandoned quartzite heap. My findings validate that a well-drained substrate with a thin humus layer or barren ground together with the occurrence of bryophytes (not Sphagnum spp.) had the highest abundance of fructiose lichens. In contrast, abundant organic soil layer, high soil moisture, and extensive cover of graminoids and herbs showed low abundance of fructiose lichens. I conclude that reindeer lichens are indeed present in a few findings but are still facing environmental and dispersal limitations to become abundant. These limitations can be understood in the light of moisture regimes, instability or compaction of substrate, and limitations within the colonization-pool, and are further discussed with suggested revegetation implementations.
254

Controles da produção primária em um Córrego de Mata Atlântica / Controls of primary production in an Atlantic Rainforest Stream

Cristiano Yuji Sasada Sato 24 February 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta dissertação consiste de dois capítulos, cada um correspondendo a um estudo realizado de modo independente. Em um córrego de Mata Atlântica, Rio de Janeiro, Brasil, foram estudados efeitos de herbívoros e de controles ambientais no perifíton. No primeiro trabalho foram testados os efeitos do camarão Potimirim glabra, um engenheiro do ecossistema, nos parâmetros metabólicos de comunidades perifíticas (Produção, Respiração, Metabolismo Líquido da Comunidade e razão Produção:Respiração). O tratamento de inclusão de Potimirim produziu resultados inversos aos esperados, com aumento da clorofila e massa seca das comunidades perifíticas, levantando dúvida com relação à eficácia dos tratamentos. Nenhuma das variáveis metabólicas esteve relacionada aos tratamentos. Considera-se que efeitos artefato da gaiola utilizada na inclusão dos camarões podem ter prejudicado o efeito esperado de remoção de material pelos camarões. Os resultados podem indicar, entretanto, que para o efeito de herbívoros os parâmetros clorofila e massa seca sejam mais sensíveis e variáveis que os metabólicos para as comunidades estudadas. São recomendados futuros trabalhos com metodologias que reduzam os efeitos artefato, tais como exclusão de herbívoros com cercas elétricas. No segundo trabalho, foram estudados os estoques, a distribuição e os controles da biomassa perifítica para o córrego. Entre os substratos estudados, a areia apresentou os maiores estoques, com 5 vezes mais clorofila e 20 vezes mais massa seca que os substratos pedra e folha. Diferenças entre trechos com diferentes densidades do camarão herbívoro Potimirim glabra revelaram para o substrato pedra menores valores de massa seca para os locais onde o camarão é mais numeroso. Entre as variáveis ambientais, apenas a profundidade esteve relacionada aos dados de biomassa nos substratos pedra e areia. A comparação dos dados deste estudo com trabalhos anteriores pode indicar que distúrbios provocados por enchentes podem alterar os estoques e os padrões de distribuição para este córrego. / This dissertation consists of two chapters, each corresponding to an independent study. In an Atlantic Rainforest stream, Rio de Janeiro, Brazil, the effects of herbivores and of environmental controls on periphyton were studied. In the first experiment I tested the effects of the shrimp Potimirim glabra, an ecosystem engineer, on the metabolic parameters of periphytic communities (Production, Respiration, Net Daily Metabolism and Production:Respiration ratio). The Potimirim inclusion treatments produced results opposite to the expected, with higher chlorophyll and dry mass of the periphytic communities. This lead to doubt of the efficacy of the treatments. None of the metabolic variables was related to the treatments. It is considered that artificial effects of the cage used in the shrimp inclusion may have changed the expected effect of material removal by the shrimps. The results may hint, however, that the chlorophyll and dry mass parameters may be more sensitive to and variable with the effects of herbivores than the metabolic parameters in the studied communities. Future work is recommended with methods that reduce artificial effects, such as herbivore exclusion using electric fences. In the second experiment, stocks, distribution and controls of periphytic biomass were studied for the stream. Among the studied substrates, sand presented the highest stocks, with 5 times more chlorophyll and 20 times more dry mass than the rock and leaf substrates. Differences among reaches with different densities of the herbivore shrimp Potimirim glabra revealed for the stone substrate smaller dry mass values in the reaches where the shrimp is more abundant. Among environmental variables, only depth was related to biomass, in the substrates rock and sand. The comparison of data in this study with previous work may hint that disturbances caused by spates may change stocks and distribution patterns for this stream.
255

Utilização de substrato artificial em cultivo do camarão Litopenaeus vannamei, em água oligohalina e meio heterotrófico

MONTEIRO, Sâmia Régia Rocha 29 August 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-21T16:48:08Z No. of bitstreams: 1 Samia Regia Rocha Monteiro.pdf: 361943 bytes, checksum: 282e86342e0a7dc7cefcb1a57d78fd60 (MD5) / Made available in DSpace on 2017-02-21T16:48:08Z (GMT). No. of bitstreams: 1 Samia Regia Rocha Monteiro.pdf: 361943 bytes, checksum: 282e86342e0a7dc7cefcb1a57d78fd60 (MD5) Previous issue date: 2008-08-29 / The use of artificial substrates in aquaculture has been used to provide the increase of culture area and natural food, improving the water quality of shrimp performance. In order to maximize the survival, feed conversion and final weight of marine shrimp Litopenaeus vannamei, cultured in oligohaline water (>0.5‰) and in heterotrophic system, were evaluated the effect of adding screens as artificial substrate. Post-larvae with 10 days (PL10) were acclimated from 34‰ to 0.5‰, during 12 days. After of the acclimatization process, the postlarvae (PL22) were reared to obtain 0.3±0.1g of weight and then they were transferred to 18 fiberglass tanks (800 L of net volume) and stocked with 150 PL/tanque. The substrate percentage addition (SPA), represents 100, 150, 200, 250 and 300% of bottom area (1m2) and the control “0” SPA, it was evaluated in completely randomized design, with three replicates. During the culture, were used a 40% crude protein (CP) ration during the first 30 days, andanother with 35% CP during the a 15 days, offered daily at 8, 12 and 17 hrs. After 45 days of culture the survival ranged from 45 to 84%, between treatments with 300% and 100% of substrate, respectively. The shrimp final weight, when related to the length orbit and the time of culture, did not present statistical difference between the SPA (P>0.05). In the ratio length and culture time, the treatment 300% was statistical different in the SPA-0, 200 and 250%. In conclusion, the use of artificial substrate increased the variables weight gain, feed conversion ratio, growth rate and survival when using SPA between 87.8 and 166.7%. / O uso de substratos artificiais na aqüicultura vem sendo utilizado para disponibilizar maior área de cultivo e alimento natural, melhorando a qualidade de água e desempenho do camarão. Objetivando maximizar a sobrevivência, conversão alimentar e peso final do camarão marinho Litopenaeus vannamei, quando cultivado em água oligohalina (>0,5‰) e em meio heterotrófico, foram avaliadas a influência da adição de telas como substrato artificial. Pós-larvas com 10 dias (PL10) foram aclimatadas de 34‰ para 0,5‰, durante um período de 12 dias. Ao final do processo de aclimatação, as pós-larvas (PL22) foram cultivadas até se obter o peso de 0,3+0,1g e, posteriormente, foram transferidas para 18 tanques de fibra de vidro (800L de volume útil) e estocadas com 150 PL/tanque. A porcentagem de adição de substrato (PAS) foi representada por 100, 150, 200, 250 e 300% da área de fundo dos tanques (1,0 m2), e o controle com “0” de PAS, analisadas em delineamento inteiramente casualizado, com três repetições. Durante a fase de cultivo, foi utilizada, nos 30 primeiros dias, ração com40% de proteína bruta (PB) e nos 15 posteriores, com 35% PB, administrada diariamente às 8, 12 e 17 horas. Ao final de 45 dias de cultivo, a sobrevivência variou de 45 a 84%, entre os tratamentos com 300% e 100% de substrato, respectivamente. O peso final dos camarões, quando relacionado ao comprimento orbital e ao tempo de cultivo, não teve diferença estatística entre as PAS (P>0,05). Na relação entre comprimento com o tempo de cultivo, as PAS de 0, 200 e 250% diferenciaram de 300%. Conclui-se que o uso de substrato artificial favorece as variáveis ganho de peso, fator de conversão alimentar, taxa de crescimento diária e sobrevivência quando se utiliza PAS entre 87,8 e 166,7%.
256

Volume e granulometria do substrato na formação de mudas de café. / Substrate volume and granulometer in coffee seedlings production.

Julio Eduardo Tavares Junior 19 March 2004 (has links)
Este trabalho foi realizado com o objetivo de avaliar a influência do volume e da granulometria do substrato comercial, utilizado na produção de mudas em tubetes, sobre o crescimento vegetativo das plantas de café, bem como o tempo de formação das mudas e a estabilidade ao manuseio do conjunto muda-substrato. O experimento foi conduzido no viveiro do Centro de Café do IAC, localizado na Fazenda Santa Elisa, Campinas, SP, utilizando a cultivar Catuaí Vermelho IAC 144 (Coffea arabica L.). Foram adotados nove tratamentos com quatro repetições, com delineamento de blocos ao acaso em esquema fatorial 3 x 3, formado pela combinação de três volumes de substrato (50, 120 e 200 cm3) e três granulometrias proporcionadas pelas seguintes composições granulométricas: 100% de substrato comercial na granulometria original, 100% de substrato comercial finamente moído e pela mistura, em volume, de 50% de substrato na granulometria comercial com 50% de substrato moído. A influência das variáveis (volume e granulometria) do substrato no crescimento das mudas de café foi avaliada por meio das determinações dos parâmetros biométricos vegetativo da parte aérea e raízes como: número de pares de folhas, altura da planta, diâmetro do caule, matéria seca da parte aérea e das raízes, área foliar total, área foliar média, área do 1o par de folhas, comprimento e superfície de raízes. Em complemento aos objetivos do trabalho foram, também, avaliados o tempo de formação das mudas e a estabilidade ao manuseio do conjunto muda-substrato. O crescimento das plantas depende do volume e da granulometria do substrato, sendo maior com a utilização de 200 cm3 de substrato e a diminuição da granulometria pela mistura, em partes iguais, do substrato finamente moído com o substrato comercial na granulometria original. O tempo de formação das mudas correlacionou com o volume de substrato, demandando 134, 124 e 81 dias para a emissão do 4o par de folhas, quando as plantas cresceram nos recipientes com 50, 120 e 200 cm3 de substrato, respectivamente. A estabilidade ao manuseio do conjunto mudasubstrato varia com o tamanho do recipiente, sendo maior nos tubetes com 50 e 120 cm3 de substrato, e a redução parcial da granulometria, pela mistura granulométrica, aumentou a aderência das partículas com as raízes e, portanto, a estabilidade do conjunto. / The objectives of this research are the evaluation of substrate volume and granulometer influence - used in production of coffee seedlings in plastic tubes - on coffee plants growth, the time of seedlings development and also seedling-substrate handling stability. The investigation was carried out in a nursery at Coffee Experimental Center of IAC, SP, Brazil, with the cultivar Catuaí Vermelho IAC 144 (Coffea arabica L.). Nine treatments were tested with 4 replicates and the experimental design used was randomized blocks with 3x3 factorial composed by 3 substrate volumes (50, 120 and 200 cm3) and 3 granulometer substrate levels obtained by the following granulometer compositions: 100% of substrate on original granulometer, 100% of crushed substrate and the mix, in volume, of 50% of substrate on original granulometer and 50% of crushed substrate. The substrate volume and granulometer influence on coffee seedlings growth was evaluated by determination of growth parameters of shoot and root as: number of leaves, seedling height, stem diameter, root and shoot dry matter, total leaf area, average leaf area, first leaf area, root length and surface. In addition to these parameters, the time of seedlings development and seedling-substrate handling stability were also investigated. The seedlings growth depend on substrate volume and granulometer, being higher when 200 cm3 of substrate volume are used keeping an equal proportion of the different substrate granulometers (original and crushed). The time of seedlings growth did show a correlation with the substrate volume demanding 134, 124 and 81 days for developing the 4th leaf pair when the plants developed in 50, 120 and 200 cm3 of substrate, respectivelly. The seedling-substrate handling stability differs with recipient size, while the granulometer reduction increases the seedling-substrate stability.
257

Fungos micorrÃzios arbusculares no desenvolvimento do meloeiro, cultivado em substrato de pà de coco, solo e vermicomposto / Arbuscular mycorrhizal fungi in the development of melon cultivated in coconut dust substrate, soil and vermicompost

Josà Maria Tupinambà da Silva JÃnior 12 May 2008 (has links)
nÃo hà / A cultura do melÃo assume grande importÃncia econÃmica no estado do CearÃ, notadamente nas exportaÃÃes da fruta que aumentam a cada ano. No entanto, para manter essa alta produtividade à necessÃria a formaÃÃo de mudas sadias em substratos adequados e que suportem as condiÃÃes do campo. A utilizaÃÃo do pà de coco seco ou verde em composiÃÃes de substratos e em conjunto com inoculaÃÃo de Fungos MicorrÃzicos Arbusculares (FMA) à recomendado, uma vez que o pà de coco à substrato natural, biodegradÃvel e de baixo custo. AlÃm disso, a inoculaÃÃo com FMA tornarà as mudas mais resistentes ao transplantio para o campo bem como aumentarà a capacidade das mudas de absorver nutrientes, principalmente o fÃsforo. O presente trabalho teve por objetivos testar diferentes concentraÃÃes de substratos (pà de coco seco, verde e solo) na colonizaÃÃo micorrÃzica do melÃo e avaliar o efeito da adubaÃÃo orgÃnica do solo em mudas de melÃo inoculadas com FMA e produzidas em substratos, pà de coco seco ou verde em ambiente estÃril e nÃo estÃril. Para tanto, dois experimentos foram conduzidos em casa-de-vegetaÃÃo pertencente ao Departamento de CiÃncias do Solo da Universidade Federal do Cearà no Campus do Pici, Fortaleza-CE. O delineamento experimental adotado nos experimentos foi o inteiramente casualizado, com dez e oito tratamentos, respectivamente nos Experimentos 1 e 2, e quatro repetiÃÃes. Foram assim constituÃdos os tratamentos do experimento 1: 70% de Pà de coco seco (PCS) ou verde (PCV) mais 30% Solo inoculado ou nÃo com FMA; 30% PCS ou PCV mais 70% Solo inoculado ou nÃo com FMA e 100% Solo com ou sem inoculaÃÃo. No Experimento 2 as sementes foram germinadas nas duas melhores composiÃÃes de substrato inoculado com FMA e transplantadas para vasos contendo solo estÃril ou nÃo, adubado ou nÃo com composto orgÃnico. Ao final de 30 dias apÃs a germinaÃÃo ou transplantio, as plantas foram coletadas e determinaram-se as variÃveis de crescimento, as variÃveis microbiolÃgicas e conteÃdo de macro e micro nutrientes na parte aÃrea. Foi observado no Experimento 1 que as composiÃÃes de substratos formados por 30% de PCS ou PCV mais 70% Solo inoculado com FMA apresentaram os melhores valores para as variÃveis de crescimento e conteÃdos dos nutrientes analisadas. As composiÃÃes de substratos formados com 70% de pà de coco verde x foram os que mais restringiram o crescimento e desenvolvimento das plantas de melÃo. No Experimento 2 as plantas adubadas com composto orgÃnico tiveram os maiores valores de matÃria seca e fresca da parte aÃrea, altura e conteÃdos de nutrientes analisados independente do solo ser estÃril ou nÃo estÃril. A adubaÃÃo orgÃnica favoreceu a absorÃÃo de fÃsforo pelas plantas, principalmente em condiÃÃes de solo nÃo estÃril, indicando que as espÃcies de FMA prÃ-inoculadas possuem grande capacidade adaptativa e competitiva em relaÃÃo aos FMA nativos. / Melon culture has a great economic importance in the State of CearÃ, Brazil, especially in fruit exportation to others countries. But to maintain that high productivity, healthy seedlings growing in suitable substrates that sustain plants in the field after transplanting are necessary. The use of dry or green coconut dust as a substrate composition associated with arbuscular mycorrhizal fungi inoculation is a recommended procedure, as coconut dust is a low cost natural biodegradable substrate. Arbuscular mycorrhizal soil inoculation makes seedlings more resistant to transplanting and increase nutrients absorption capacity, especially phosphorus. The objective of this dissertation was to evaluate different substrates concentrations (dry and green coconut dust and soil) on melon arbuscular mycorrhizal colonization (Experiment 1) and the effect of organic matter fertilization on AMF inoculated plants growing in a sterile and non-sterile soil, under greenhouse conditions. A randomized statistical design was adopted, with ten and eight treatments, respectively to Experiments 1 and 2, and four replications. Thirty days after germination or transplanting, plants were harvested and analyzed for their growth and microbiological variables and shoot nutrients content. Substrates compositions with 30% of dry or green coconut dust and inoculated with AMF increased melon growth as compared with higher concentrations. Sterilized or non-sterilized soil condition does not influenced plants development under organic fertilization. Addition of organic compost increased phosphorus uptake by plants grown on non-sterile soil, indicating a high competition capacity of pre-inoculated plants transplanted to non-sterile soil.
258

Contribuição ao estudo do crescimento de Candida utilis IZ-1840 em glicerol, adaptação de um modelo de inibição por substrato / Contribution to study of the growth of Candida utilis IZ-1840 in glycerol, adaptation by one model of substrate inhibition

Dante Augusto Moraes 19 April 1994 (has links)
Estudou-se a influência da concentração inicial de substrato no cultivo em fermentador para produção de biomassa de Candida utilis IZ-1840 em meio sintético tamponado contendo glicerol (1,2,3-propanotriol) como fonte exclusiva de carbono nas seguintes concentrações: 15, 25, 35, 45, 55, 65 e 75 g/L com ensaios em duplicata. Observou-se um comportamento cinético característico de fenômeno de inibição por substrato, tendo-se então ajustada uma equação de modelo de inibição baseada na literatura para os dados de velocidade específica máxima de crescimento celular em função da concentração inicial de substrato. A partir de tal equação determinou-se o valor da concentração inicial de substrato onde não ocorre inibição, definido como S* ( S*=17,511 g/L) e o valor teórico acima do qual a inibição é máxima definido como Sm, (Sm=175,4 g/L). O valor teórico de velocidade específica máxima de crescimento celular, definido como &#181;* correspondente ao valor S* como concentração de substrato inicial foi calculada em 0,225 1/h. / The influence of initial substrate concentration in the growth of Candida utilis IZ-1840 in a buffered synthetic mediurn was studied utilizing glycerol (1,2,3-propanetriol) as an exc1usive carbon source, in the following concentrations: 15, 25, 35, 45, 55, 65 and 75 of in double assays. Characteristic kinetic behavior of substrate inhibition was detected, then one model equation of inhibition based on literature was adjusted for the maximum specific growth rate in function of the initial substrate concentration. From this equation it was possible to determine the value of the initial substrate concentration that do not occur growth inhibition, defined as S* (S* = 17,511 g/L).and the theoretical value of limit concentration where above this the growth inhibition becomes maximum which was defined as Sm (Sm = 175,4 g/L). The theoretical value for maximum specific growth rate, defmed as &#181;* corresponding to determined S* as initial substrate concentration was calculated in 0,225 1/h.
259

Projeto conceitual e construção de um protótipo de uma minimáquina para o corte de substratos de Alumina / Conceptual project and construction of a mini dicing prototy to cut Alumina substrate

Luis Antonio Oliveira Araujo 16 September 2009 (has links)
O trabalho aborda o processo de corte de substrato cerâmico, estuda e propõe uma estratégia de projeto para a concepção e tomada de decisões de uma mini dicing saw. A tecnologia dos componentes eletrônicos modernos esta baseada no emprego de finos e estreitos substratos cerâmicos ou de silício. Uma das técnicas para a obtenção destas peças, faz uso da segmentação do substrato maior onde são depositadas as trilhas e os componentes de milhares de partes. O corte desses substratos, quando feito por meio abrasivos, emprega discos superabrasivos de espessura próxima a 0,2 mm e velocidades periféricas acima de 30 m/s. Nestas condições é exigido baixo ruído, alta precisão de giro e elevada velocidade rotacional, geralmente obtido através de mancais aerostáticos cerâmicos. O trabalho foi organizado em projeto conceitual e construção de um protótipo de uma dicing saw ou dicing machine. O protótipo admite peças com dimensões de até 100 x 100 mm podendo cortar até 5 mm de profundidade dependendo do diâmetro do disco de corte. O trabalho avalia condições de corte, como: velocidade de avanço de corte, desgaste e velocidade de rotação do disco abrasivo, profundidade de corte e a qualidade final do corte, como: trincas, lascas, linearidade do corte, características estas qualificadas e quantificadas por microscopia eletrônica de varredura (MEV) e perfilometria. Estudos preliminares de corte de blocos de Alumina foram realizados, detectando condições estáveis de produção na faixa de 5 a 13 mm/s. Menor desgaste do disco em baixas rotações e maiores esforços de corte em grandes profundidades de penetração e avanço do disco abrasivo. / This work studies the dicing process of ceramic parts and proposes a project strategy to concept and take decisions about configuration for a preliminary project and the construction of a dicing saw or dicing machine prototype. The technology used by modern electronic components is based on narrow and thin ceramic or silicon. One of the techniques to obtain these products is to dice a larger substrate using an abrasive blade to generate low damages and high productivity. The dicing abrasive process uses abrasive blades with thickness around 0,2 mm and peripherycal speeds of 30 m/s. On these conditions, low noise, high precision and high rotation is required, conditions generated by ceramic aerostatic spindles. This work is managed in preliminary project and construction of a dicing saw or dicing machine prototype. This prototype is able to cut substrates with square shape 100 x 100 mm and depth of 5 mm depending on the blade diameter. This work tests cutting conditions as: feed rate, blade wear, blade speed, and also test the die final quality as: chipping, cracking, dicing linearity. Quantity and quality characteristics were both verified by electronic microscopes and perfilometry. Preliminary studies about dicing ceramic parts detected stable production in 5 to 13 mm/s. Lower blade wear in lower rotations and higher cutting forces in higher cutting depth and feed rate.
260

Estudos do uso da citocinina BAP e do gongocomposto na estaquia da Pitaieira (Hylocereus undatus) / Studies of the use of cytokinin BAP and millipede-compost on Pitaia (Hylocereus undatus) propagated by cuttings

CRUVINEL, F?bio Ferreira 21 February 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-02-20T18:25:57Z No. of bitstreams: 1 2017 - F?bio Ferreira Cruvinel.pdf: 1438823 bytes, checksum: 49768f1c89baea668d06d925b16c5e0c (MD5) / Made available in DSpace on 2018-02-20T18:25:57Z (GMT). No. of bitstreams: 1 2017 - F?bio Ferreira Cruvinel.pdf: 1438823 bytes, checksum: 49768f1c89baea668d06d925b16c5e0c (MD5) Previous issue date: 2017-02-21 / CAPES / The pitaya (Hylocereus undatus (Haw.) Britton & Rose) has an exotic shape, pleasant taste, easy digestibility and antioxidant properties, which have given greater demands in the Brazilian market for this fruit in recent years. The production of seedlings is a determining factor for the successful installation of pitaias orchards and the use of phytoregulators such as BAP (6-benzylaminopurine) and organic substrates, such as millipede-compost, in the production of seedlings of this fruit is still little reported. The objective of this work was to analyze the effect of BAP and millipede-compost on the production of pitaia seedlings. Pitaia cuttings from Fazendinha Agroecol?gica - Km 47, in the town of Serop?dica-RJ, were used. The stakes were standardized with 20 cm in length. The experiment with the phytoregulator was conducted in the greenhouse sector of the UFRRJ and the cuttings planted in substrate composed of sand and bovine manure in a ratio of 1: 1 by volume in a completely randomized design (DIC) in a factorial scheme (2X4) with 4 replicates: (2) By immersion and incision made at the apex of cladodes stakes versus (4) four doses of BAP (0, 50, 100 and 150 mg.L-1) were applied. Non-destructive Growth Analysis was performed and the simple correlations were calculated with the climatic data obtained at the Ecologia Automatic Station in Serop?dica-RJ. For the experiment with the millipede compost, the cutting was conducted in pots with three types of substrates: Gongocomposto, Biomix? and sand + bovine manure (1: 1 by volume) in DIC with five replicates. The results showed a linear tendency in number of shoots and quadratic tendency in other parameters (length, fresh and dry weight) evaluated with use of BAP. There was a correlation between the growth rates of the pitaya with the data of Global Solar Radiation of the 19h (22h UTC) period. The use of the gongocomposto showed larger and more vigorous plants of pitaia. / O fruto da pitaieira (Hylocereus undatus (Haw.) Britton & Rose) apresenta forma ex?tica, sabor agrad?vel, f?cil digestibilidade e propriedades antioxidantes, caracter?sticas essas que proporcionaram maiores demandas no mercado brasileiro por essa fruta nos ?ltimos anos. A produ??o de mudas ? um fator determinante para o sucesso da instala??o de pomares de pitaias e o uso de fitorreguladores como o BAP (6-benzilaminopurina) e substratos org?nicos, como o gongocomposto, na produ??o de mudas desta frut?fera ainda ? pouco relatado. O objetivo deste trabalho foi analisar o efeito do BAP e gongocomposto na produ??o de mudas de pitaia. Utilizaram-se estacas de pitaieira proveniente da Fazendinha Agroecol?gica ? Km 47, no munic?pio de Serop?dica-RJ. As estacas foram padronizadas com 20 cm de comprimento. O experimento com o fitorregulador foi conduzido no setor de olericultura da UFRRJ, em casa de vegeta??o e as estacas plantadas em substrato composto por areia e esterco bovino na propor??o 1:1 em volume em Delineamento Inteiramente Casualizado (DIC), com 4 repeti??es, em esquema fatorial (2X4), sendo (2) por imers?o e incis?o feita no ?pice das estacas dos clad?dios versus (4) quatro doses da citocinina BAP (0, 50, 100 e 150 mg.L-1). Foi realizada a An?lise de Crescimento n?o destrutiva e foram calculadas as correla??es simples com os dados clim?ticos obtidos na Esta??o Autom?tica Ecologia em Serop?dica-RJ. Para o experimento com o gongocomposto a estaquia foi conduzida em vasos com tr?s tipos de substratos: Gongocomposto, Biomix? e areia+esterco bovino (1:1 em volume) em DIC com cinco repeti??es. Os resultados mostraram uma tend?ncia linear positiva no n?mero de brota??es e quadr?tica para o incremento de comprimento, peso fresco e seco das brota??es para o uso da citocinina BAP no incremento de. Houve correla??o entre as taxas de crescimento da pitaia com os dados de Radia??o Solar Global do per?odo das 19h (22h UTC). O uso do gongocomposto proporcionou maiores e mais vigorosas mudas de pitaieira.

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