41 |
Estudo de pré - tratamentos de palha e sabugo de milho visando a produção de etanol 2G / Study of pretreatments of husk and corn COB seeking the ethanol 2G productionSantos, Martha Suzana Rodrigues dos 26 February 2014 (has links)
Petroleum and its derivatives make up the largest portion of Brazil’s current energy matrix. It is well known that these are non-renewable and pollution-causing sources of energy; as such, the last decades have been marked by research and development of new, cleaner technologies. One of them being the hydrolysis of lignocellulosic materials to produce bioethanol. Brazil has an ample variety and large volumes of lignocellulosic biomass like corn husk and corncob. However, these biomass sources have complex structures which give rise to difficulties during the posterior stages of hydrolysis. Thus, it becomes necessary to conduct a pretreatment in order to alter these complex structures and make them more accessible to attack by microorganisms and enzymes. This work investigated two pretreatment methods for biomass coming from corn husk and corncob: pretreatment with dilute sulfuric acid and hydrothermal pretreatment; aiming to determine which method was more suitable for the given experimental conditions. An experimental design method was used to determine the best operating conditions for the acid pretreatment. Chemical characterization was used to evaluate the efficiency of the hydrothermal pretreatment. Both biomass sources were analyzed via Superior Calorific Power (SCP) resulting in17.276,5 J/g for corn husk and 17.872,0 J/g for corncob. Regarding the hydrothermal pretreatment, results showed reduction of the three components of biomass: cellulose, hemicellulose and lignin. Ideally, cellulose should not be degraded during the pretreatment. Therefore, the conditions leading to the lowest cellulose removal were determined: corn husk pretreatment at 170°C for 15 minutes and corncob pretreatment at 195°C for 10 minutes. The factors evaluated during the sulfuric acid pretreatment were: concentration, heating time and temperature. The two-variable factorial experiment with three replicates suggested that the highest reduced sugar percentages are obtained with low acid concentrations and high temperatures. Moreover, time was not a significant factor. Test 3 and 12 yielded the best results for both sources of biomass. The conditions for test 3 were: 120°C, a 15 minutes heating time and 0,5% sulfuric acid which resulted in 50,9% reduced sugars for corn husk and 42,6% for corncob. The conditions for test 12 were: 110°C, a 7 minutes heating time, and 2% sulfuric acid which resulted in 59,4% reduced sugars for corn husk and 61,5% for corncob. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / No panorama energético atual, nota-se que a utilização do petróleo e seus derivados ainda têm representado a maior fonte de energia em nosso país. Visto que essas fontes são não renováveis e poluentes, a necessidade de utilização de outras rotas, que sejam mais limpas, tem crescido ao longo dos anos. Quando se trata de materiais lignocelulósicos para a produção do bioetanol, encontra-se uma ampla variedade de biomassas, como é o caso da palha e do sabugo do milho. Porém essas biomassas possuem uma estrutura complexa, que dificulta as etapas posteriores de hidrólise. Logo, torna-se imprescindível a realização de um pré-tratamento que irá alterar essa estrutura, tornando-a mais acessível ao ataque de microrganismos e enzimas. Nesse trabalho, dois tipos de pré-tratamentos foram estudados, o pré-tratamento com ácido sulfúrico diluído e o pré-tratamento hidrotérmico, com o intuito de avaliar o mais viável, levando em conta todos os fatores envolvidos. O planejamento experimental foi uma ferramenta utilizada para a escolha das melhores condições operacionais do pré-tratamento com ácido diluído. Uma caracterização química foi realizada para avaliar a eficiência do pré-tratamento hidrotérmico. Análises de poder calorífico superior (PCS) também foram realizadas com as duas matérias-primas e os resultados do PCS foram de 17.276,5 J/g para a palha de milho e de 17.872,0 J/g para o sabugo. Em relação ao pré-tratamento hidrotérmico realizado, os resultados mostraram redução nos três componentes: celulose, hemicelulose e lignina. O¬¬¬¬ ideal é que a celulose sofra desorganização, contudo que não seja degradada, porém aqui se avaliou a melhor condição pela menor remoção de celulose, que foi dada com o pré-tratamento da palha de milho sob as condições de 170°C por 15 minutos e com o pré- tratamento do sabugo sob as condições de 195°C por 10 minutos. Já com relação ao pré-tratamento ácido, que ocorreu com utilização dos fatores: concentração de ácido sulfúrico, temperatura e tempo de aquecimento, um planejamento experimental em estrela com triplicata no ponto central mostrou que maiores percentuais de ART são dados quando se trabalha com baixas concentrações de ácido e elevadas temperaturas, na faixa investigada. O fator tempo não se mostrou significativo. As melhores condições foram obtidas nos ensaios 3 e 12 para ambas as biomassas. Com a temperatura de 120°C, tempo de 15 minutos e 0,5% de concentração de ácido sulfúrico, condição 3, obteve-se 50,9% de ART para a palha e 42,6% para o sabugo. Já com a temperatura de 110°C, tempo de 7 minutos e 2% de ácido, que foi a condição 12, obteve-se 59,4% de ART para a palha e 61,5% para o sabugo.
|
42 |
Obtenção de nanocristais de celulose a partir do resíduo da produção de etanol do bagaço de cana-deaçúcar pela rota enzimática / OBTAINING CELLULOSE NANOCRYSTALS FROM THE RESIDUE OF ETHANOL PRODUCTION FROM SUGARCANE BAGASSE BY ENZYMATIC ROUTECamargo, Lais Angelice de 30 July 2015 (has links)
Submitted by Luciana Sebin (lusebin@ufscar.br) on 2016-09-14T19:04:53Z
No. of bitstreams: 1
DissLACon.pdf: 3897175 bytes, checksum: 00c39fb2aaba768abfa726b4ee62d2cc (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-15T14:24:30Z (GMT) No. of bitstreams: 1
DissLACon.pdf: 3897175 bytes, checksum: 00c39fb2aaba768abfa726b4ee62d2cc (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-15T14:24:41Z (GMT) No. of bitstreams: 1
DissLACon.pdf: 3897175 bytes, checksum: 00c39fb2aaba768abfa726b4ee62d2cc (MD5) / Made available in DSpace on 2016-09-15T14:24:48Z (GMT). No. of bitstreams: 1
DissLACon.pdf: 3897175 bytes, checksum: 00c39fb2aaba768abfa726b4ee62d2cc (MD5)
Previous issue date: 2015-07-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / This study addressed the use of solid residues from the process of cellulosic ethanol production using the enzymatic hydrolysis of sugarcane bagasse for the production of cellulose nanocrystals (CNCs). Bagasse submitted to two types of pretreatments (steam explosion - SESB and hydrothermal - HSB) was hydrolyzed with two different enzymatic loads using a commercial enzymatic extract. The solid residues generated after the hydrolysis were purified with NaOH 5% (w/w) at 55 °C and H2O2 35% (v/v)
followed by an acid hydrolysis at 45 °C with H2SO4 60% (w/w) and extraction of 30 min in order to obtain the CNCs. The samples of SESB and HSB presented cellulose contents of 61 and 54%, respectively. The conversion in the enzymatic hydrolysis step ranged from 25 to 55% for SESB and 33 to 59% for HSB, along with the increase of enzymatic loading. And besides the release of glucose into the liquid phase, it was also generated solid residues with significant quantity of cellulose to be
used for CNCs production. Due to decreasing of the cellulose crystallinity indexes (CI%) of the residual solid, a purification procedure was necessary, which raised the CI by about 30% for SESB residues and approximately 25% for HSB residues. The resulting CNCs presented proper physical and chemical characteristics, such as degradation temperature exceeding 230°C and crystallinity around 79% for both
matrices. The CNCs obtained feature of needle with length between 193 and 246 nm and diameter of between 17 and 30 nm. These results indicate that CNCs produced from the residual streams of enzymatic route of cellulosic ethanol production from the sugarcane bagasse have the characteristics suitable for this type of product. Therefore, the use of these solids residues for new materials production, such as NCCs for use in different applications proved to be potentially promising for adding value to the bioenergy sector. / O presente estudo avaliou o emprego dos resíduos sólidos do processo de produção de etanol celulósico a partir da hidrólise enzimática do bagaço de cana-de-açúcar para a produção de nanocristais de celulose (NCCs). Bagaço submetido a dois tipos de pré-tratamentos (explosão a vapor - BEX e hidrotérmico - BH) foi hidrolisado com duas diferentes cargas enzimáticas utilizando um extrato enzimático comercial. Os resíduos sólidos gerados após a hidrólise foram purificados com NaOH 5% (m/m) a 55oC e H2O2 35% (v/v) seguido de uma hidrólise ácida a 45oC com H2SO4 60% (m/m) e extração de 30 min, visando a obtenção dos NCCs. As amostras de BEX e BH apresentaram teores de 61 e 54% de celulose, respectivamente. A conversão na etapa de hidrólise enzimática variou de 25 a 55% para o BEX e de 33 a 59% para o BH, com o aumento da carga enzimática. Assim, além da liberação da glicose para a fase líquida, na etapa de hidrólise enzimática foi gerado um resíduo sólido com quantidade significativa de celulose para os processos subsequentes de obtenção de NCCs. Devido à diminuição dos índices de cristalinidade da celulose (IC%) dos sólidos residuais, foi necessário um procedimento de purificação que elevou o IC% em aproximadamente 30% para os resíduos do BEX e aproximadamente 25% para os resíduos do BH. A partir disso, os NCCs apresentaram características físico-químicas adequadas, como temperatura de degradação superior a 230°C e cristalinidade próxima de 79% para ambas as matrizes. Os NCCs obtidos apresentaram formato de agulha com comprimento entre 193 e 246 nm e diâmetro entre 17 e 30 nm. Esses resultados indicam que os NCCs produzidos a partir das correntes residuais da rota enzimática de produção de etanol celulósico a partir do bagaço de cana-de-açúcar possuem as características adequadas para esse tipo de produto. Portanto, a utilização desses resíduos sólidos
para a produção de novos materiais, tais como os NCCs para aplicações em diversos setores industriais, mostrou-se potencialmente promissora para a agregação de valor ao setor de bioenergia.
|
43 |
Paper spray ionization: análise direta de licores do processo de etanol 2G por espectrometria de massas / Paper spray ionization: direct analysis of liquors of 2G ethanol by mass spectrometryCarvalho, Thays Colletes de 06 March 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-19T11:42:47Z
No. of bitstreams: 2
Dissertação - Thays Colletes de Carvalho - 2015.pdf: 2499571 bytes, checksum: fe876dabf52c3d28675aeb6e1dae2d21 (MD5)
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-19T11:44:31Z (GMT) No. of bitstreams: 2
Dissertação - Thays Colletes de Carvalho - 2015.pdf: 2499571 bytes, checksum: fe876dabf52c3d28675aeb6e1dae2d21 (MD5)
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-19T11:44:31Z (GMT). No. of bitstreams: 2
Dissertação - Thays Colletes de Carvalho - 2015.pdf: 2499571 bytes, checksum: fe876dabf52c3d28675aeb6e1dae2d21 (MD5)
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
Previous issue date: 2015-03-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / 2G Ethanol production is a laborious process that may result in formation
of glucose -fermenting yeasts, which reduces the process yield. The
search for new rapid and sensitive methods are required to show the
condition with the formation of free sugars and absence of fermentation
inhibitors (Hidroximetilfurfural and furfural). The present work proposes
utilizing the Paper Spray (PS) Ionization source as a method of detecting
and quantifying fermentation yeasts inhibitors and sugars generated in 2G
ethanol-acquiring processes. The method was optimized and was
obtained as calibration curves for the glucose obtained by enzymatic
hydrolysis process. These conditions were used for analysis actual sample
of sugarcane bagasse liquors. The best analysis conditions by PS were:
distance between 1 and 5 mm, dry spot application mode, Whatman
Grade 1 paper, 60º angle, modified paper with paraffin barrier, 10 μL
volume and sample application concentration of 0,1mg/mL. The detection
of the expected product in the pretreatment and hydrolysis liquors of
sugarcane bagasse was performed as expected. The paper with paraffin
channel proved to be more effective for the quantification of glucose with
improved linearity (0.9952) and limits of detection (2.77 mmol/L) and
quantification (9.27 mmol/L) compared to without changing paper and
paper cur ends. Applying the PS prototype in determining sugars and
inhibitors in sugarcane bagasse liquors has proven to be efficient and
quick, opening up a perspective of utilizing this method on monitoring
Ethanol 2G production processes. / A produção de etanol 2G é um processo laborioso, que pode resultar na
formação de inibidores de leveduras fermentadoras de glicose, o que
diminui os rendimentos do processo. A busca de novas metodologias
rápidas e sensíveis são necessárias para evidenciar a condição com a
formação de açúcares livres e ausência de inibidores da fermentação
(Hidroximetilfurfural e furfural). Este trabalho apresenta a proposta de
utilizar a fonte de ionização Paper Spray Ionization (PS) como método de
detecção e quantificação de inibidores e açúcares gerados nos processos
de obtenção de etanol 2G. O método foi otimizado e obteve-se curvas de
calibração para a glicose obtida pelo processo de hidrolise enzimática.
Essas condições foram usadas para análise de amostras reais de licores
de bagaço de cana-de-açúcar. As melhores condições de análise por PS
foram: Distância entre 1 e 5 mm, modo de aplicação por aplicação a seco,
papel Whatman Grade 1, ângulo de 60°, papel modificado com barreira de
parafina, volume de 10 μL e concentração de amostra de 0,1mg/mL. A
detecção dos produtos esperados nos licores de pré-tratamento e
hidrólise do bagaço de cana-de-açúcar foi realizada como esperado. O
papel com canal de parafina mostrou-se ser mais eficaz para a
quantificação da glicose com melhor linearidade (0,9952) e limites de
detecção (2,77 mmol/L) e quantificação (9,27 mmol/L) em relação ao
papel sem modificação e o papel arredondado. A aplicação do PS na
determinação de açúcares e inibidores em licores de bagaço de cana-deaçúcar
mostrou-se eficiente e rápido abrindo a perspectiva de utilização
deste método no acompanhamento de processos de produção de etanol
2G.
|
44 |
Traffic analysis of existing traffic in Kulyab region in order to plan and configure a new GSM MSC for this region / Trafikanalys av existerande trafik i Kulyab-regionen inför planering och konfigurering av en ny GSM MSC för denna regionFrostne, Isabel January 2011 (has links)
Wide area cellular mobile networks have rapidly evolved over the years. In the beginning achieving wide area coverage was a great achievement – enabling subscribers to call from wherever they were currently located and whenever they wanted. Additionally these systems supported mobility of subscribers, so that calls could continue even while a subscriber moved from one cell to another. Today mobility management is something everyone takes for granted. New functionality is continuously being developed for these networks. An important aspect of this evolution has been to enable new applications and technologies to be introduced while maintaining interoperability with the existing technologies. These mobile networks use new technologies and enable new applications, but they interconnect with existing networks that utilize earlier technologies, such as the existing fixed telephone network. These interconnections enable communication between subscribers connected via all of these networks. In today’s mobile networks there are a variety of technologies working side by side, for example 2G, GPRS, 3G, and so on. The earlier networks used circuit switching technology, but the trend in later networks was to transition exclusively to packet switching. One of the most important network entities is the mobile switch center (MSC). In the earlier circuit switched networks the MSC is the heart of the circuit switching network. The MSC is responsible for management, control, and communication to and from the mobile stations (MSs) in the area managed by the MSC. The MSC stores information about each of the MSs in one or more databases. In the subscriber’s home network the information about their subscription is stored in a home location register (HLR), while when this subscriber is in another network information is stored in a visitor location register (VLR). The MSC together with other elements of the core network handles mobility management, enabling both handover and roaming. A gateway MSC enables MSs to communicate with phones connected to the fixed network. The aim of this thesis is to analyze the traffic situation for Kulyab region in order to configure and install the MSC in Kulyab. For the time being there is no radio network controller (RNC) in Kulyab region, so the MSC in Kulyab will be configured to support 2G traffic. The configuration will be based on the expected mobile traffic load in the Kulyab region, thus the first steps in the process were to collect and analyze data about the existing traffic in this region that is currently served by a MSC located outside of this region. The configuration of the new MSC will be based on this analysis. After installing and configuring the new MSC some question need to be answered, namely: Can the MSC in Kulyab support all the base stations in Kulyab region? If not, how many base stations can it support? To what extent does the addition of this new MSC improve the overall network in terms of increased reliability, capacity, and throughput? How much will the capacity of the existing MSC, that is responsible for traffic outside Dushanbe, be increased due to the introduction of the new MSC? / Den mobila täckningen har utvecklats snabbt under åren. Att uppnå den mobila täckningen var i början en stor prestation – att kunna erbjuda telefontjänster för abonnenterna var än de befann sig och när de ville. Förutom detta så stödde detta system också fri rörlighet för abonnenterna. Under ett samtal kunde de förflytta sig från en cell till ett annan utan att samtalet bröts. Nu är mobilitetshanteringen någonting självklart. Nya funktioner utvecklas ständigt för dessa nätverk. En viktig aspekt för utvecklingen är att möjliggöra så att nya applikationer och teknologier kan introduceras och fortfarande vara kompatibla med de existerande teknikerna. Dessa mobilnätverk använder nya tekniker och möjliggör nya applikationer som är kompatibla med det existerande nätverket. Det existerande nätverket använder sig av tidigare teknologier, så som den fasta telefonnätet. Detta möjliggör kommunikation mellan abonnenterna från olika nätverk. I dagens nätverk finns det ett antal olika nätverk, som t.ex. 2G, GPRS, 3G och så vidare. Det tidigare nätverket använde sig av kretskopplad teknik, men trenden är attuteslutande använda sig av paketkopplad teknik. En av de viktigaste nätverksenheterna är ”Mobile switch center” (MSC). I de tidigare kretskopplade nätverket är MSC hjärtat i det kretskopplade nätverket. MSC är ansvarig för hanteringen, kontrollen och kommunikation till och från demobila enheterna (MS) i området som kontrolleras av MSCn. MSC lagrar information om var och en av MS i ett eller flera databaser. I abonnentens hemnätverk finns information om abonnentens abonnemang i ett hemregister (HLR). När abonnenten befinner sig i ett annat nätverk lagras informationen i ett gästregister (VLR). MSC hanterar mobilitet tillsammans med andra nätverksenheter i ”Core network” (CN) och möjliggör överlämnande (handover) och roaming. ”Gateway MSC” GMSC möjliggör kommunikation mellan MS och det fasta nätverket. Syftet med examensarbetet är att analysera trafiken för Kulyab-regionen för att konfigurera och installera en MSC i Kulyab. För tillfället finns ingen ”Radio network controller” (RNC) i regionen Kulyab, så MSCn i Kulyab kommer att konfigureras för att stödja 2G trafik. Konfigurationen baseras på den förväntade belastningen av mobiltrafiken i Kulyab-regionen, följaktligen är det första steget i processen att samla ihop och analysera information om den existerande trafiken i Kulyab-regionen. Trafiken tillhörande Kulyab-regionen handskas för närvarande av en MSC som befinner sig utanför detta område. Konfigurationen av den nya MSCn kommer att baseras på denna analys. Efter installationen och konfigurationen av den nya MSCn kommer följande frågor att bli besvarade, nämligen: Kan MSCn i Kulyab stödja alla basstationerna i Kulyab regionen? Om inte, hur många basstationer kan MSCn stödja? Till vilken grad kommer den nya MSCn att förbättra nätverket i termer av ökad tillförlitlighet, kapacitet och trafikgenomströmning? Hur mycket kommer kapacitetsökningen för den existerande MSC utanför Dushanbe att öka då MSC i Kulyab installeras?
|
45 |
Contribución al desarrollo de un entorno seguro de m-commercePonce Vásquez, Diego Arturo 02 July 2002 (has links)
La exitosa implantación de la telefonía móvil a escala mundial presenta una muy importante oportunidad para la expansión del comercio electrónico sobre entornos inalámbricos. El comercio electrónico para móviles, m-Commerce, implica tres aspectos básicos: 1) la negociación y el servicio en la vecindad de cliente, 2) información oportuna y georeferenciada mientras el usuario esta en movimiento, 3) la posibilidad para completar una transacción en cualquier sitio y momento. El usuario debe tener las facilidades siguientes: la negociación y la entrega inmediata, métodos rápidos de micro y de macro pago, y facilidad de uso en el ambiente de móvil. Una de las novedades del comercio móvil es la posibilidad de atraer a clientes en el vecindario hacia un centro de venta y/o servicios proporcionándoles la información apropiada. Existen, sin embargo, una serie de factores que dificultan la implantación y el desarrollo del comercio móvil respecto al comercio electrónico. Esos inconvenientes se relacionan con las características del ambiente inalámbrico: normalmente menor ancho de banda, latencia más baja, menos estabilidad de conexiones, la disponibilidad menos previsible. Y las limitaciones en los equipos móviles: la unidad de procesamiento central menos potente, menos memoria, limitaciones en el consumo de potencia, formato reducido de pantalla, y otras más.La seguridad extremo a extremo entre el servidor de Internet y el terminal móvil es indispensable para aplicaciones de comercio electrónico. La especificación de la capa de seguridad WTLS (Wireless Transport Layer Security de WAP) no proporciona este nivel de seguridad. El uso de WTLS y la seguridad a nivel de la capa de transporte TLS (Transport Layer Security) permite la privacidad en los canales inalámbrico e Internet, pero la seguridad alcanzada no es suficiente para aplicaciones de comercio electrónico; por ello se precisan mecanismos de seguridad extremo a extremo. En esta tesis se propone una alternativa a la arquitectura de la seguridad de WAP para resolver el problema mencionado, basada en la implementación de una capa de seguridad nueva dentro de la capa WAE (Wireless Application Environment). Esto hace posible la seguridad extremo a extremo, compatibilidad con TLS, transparencia ante el usuario, y se evita la traducción y descompresión en la pasarela de WAP. Varios estudios sobre usabilidad de los dispositivos con capacidades de WAP indican que los usuarios se desconectaron debido a tiempos de respuesta lentos y la falta de comodidad en el uso (interfaces no agradables, servicios costosos, . ). Los estudios coincidieron en que las velocidades más rápidas y el uso extendido de equipos móviles de datos promueven el comercio móvil, y que el número de usuarios familiarizados con equipos móviles sube constantemente, particularmente entre usuarios de WAP, de modo que estos usuarios comienzan a ver sus teléfonos móviles como algo más que meros teléfonos. La movilidad del usuario contribuye a hacer las redes inalámbricas más complejas, y constituyen los nuevos paradigmas en el intercambio de información. Las posibilidades que se abren para la Internet inalámbrica constituyen una oportunidad importante para el comercio electrónico. El futuro e impacto social de las tecnologías utilizadas, WAP, GPRS, UMTS, . son cuestionadas habitualmente. En esta tesis se analiza la posibilidad de realizar operaciones de m-Commerce sobre WAP. Por ello, se presentan los mecanismos de seguridad de WTLS (Wireless Transport Layer Security) y se analiza la seguridad extremo a extremo en este protocolo. En redes inalámbricas, existe la necesidad de acelerar la respuesta al usuario, facilitarle el uso en ambientes ruidosos, con desconexión no previsible, sobre dispositivos con formato limitado. Para paliar los problemas relacionados a la entrega de información, facilitar el uso y personalizar el servicio con el cliente, se presenta una propuesta basada en un sistema intermediario. Los objetivos de dicho intermediario son a) reducir el tráfico de datos en el canal inalámbrico delegando tareas tales como la búsqueda, interacción y filtrado de la información al Intermediario aún estando fuera de línea; b) Reutilizar contenidos: reutilizar la información residente en el almacén intermedio mediante un sistema distribuido de caches y proxies; c) Personalizar la información: conociendo previamente el perfil del usuario se puede filtrar y distribuir información en forma predictiva y d) Gestionar la información del estado de los certificados con OCSP (On-line Certificate Status Protocol).
|
46 |
Avaliação de diferentes configurações de hidrólise enzimática e fermentação utilizando bagaço de cana-de-açúcar para a produção de etanol 2G / Evaluation of different configurations of enzymatic hydrolysis and fermentation using sugarcane bagasse for 2G ethanol productionSilva, Gislene Mota da 27 March 2015 (has links)
Made available in DSpace on 2016-06-02T19:55:43Z (GMT). No. of bitstreams: 1
6832.pdf: 3214384 bytes, checksum: 0ef6f81368240fad0ee476c019e48c11 (MD5)
Previous issue date: 2015-03-27 / Universidade Federal de Sao Carlos / Sugarcane bagasse (SCB) is a by-product generated after sugarcane milling in the process of manufacture of sugar and/or ethanol. In this study, pretreated SCB was used in different configurations of enzymatic hydrolysis and fermentation. The objective was obtaining the greatest amounts of fermentable sugars in the enzymatic conversion and then converted them to ethanol. SCB was hydrothermally pretreated (1:10 (w/v), solid-liquid ratio) under the conditions 170 °C/15 min, 195°C/10 min, and 195 °C/60 min at 200 rpm. The delignification step of the hydrothermal pretreated SCB was carried out with 0.02 and 0.5% NaOH solution at 1:10 (w/v). Pretreated and untreated samples of SCB were chemical and morphologically characterized. Enzymatic hydrolysis and fermentation assays were carried out in PSSF (pre-saccharification prior to simultaneous saccharification and fermentation) process. In the best condition, (10% pretreated SCB at 195 °C/10 min) it was obtained 57.4% of ethanol yield. SSF (simultaneous saccharification and fermentation) experiments were performed in Erlenmeyer flasks at 250 rpm and at 37 °C using commercial Saccharomyces cerevisiae during 72 h. In the first assay, it was evaluated the effect of initial buffered medium and non-buffered medium for hydrothermal pretreated SCBs. In the best result, it was obtained 53.8% of enzymatic conversion and an ethanol titer of 17.1 g/L (SCB pretreated at 195 °C/10 min in buffered medium). In the next assays, it was evaluated the effect of solid loading (10 and 15%) on delignified and non-delignified SCB using an enzyme loading of 20 FPU/g pretreated SCB. In these assays were obtained ethanol yields of 53.8 (17.1 g/L) and 60.0% (28.4 g/L) for 10 and 15% of SCB, respectively. These results showed that the increased in solid loading favored obtaining higher ethanol yield. Assays in SHF configuration (separate hydrolysis and fermentation) using delignified and non-delignified samples of SCB achieve ethanol concentration of 39.9 g/L and ethanol yield was 84% with 15% loading at 72 h. Other experiments were carried out in 10% SCB/15 FPU/g SCB loading, 10% SCB/30 FPU/g SCB loading, 15% SCB/15 FPU/g SCB loading and 15% SCB/30 FPU/g SCB loading employing the thermotolerant yeasts Kluyveromyces marxianus IMB3 and Saccharomyces cerevisiae D5A to ethanol production from hydrothermal pretreated SCB. The results showed enzymatic conversion was 64.3% and maximum ethanol concentration of 29.2 g/L using 15% of SCB at 72 h. D5A yeast showed ethanol yield was 76.2% and the maximum ethanol concentration of 42.6 g/L at 120 h using 15% of solid load and 30 FPU/g SCB of enzyme load. Overall, all evaluated conditions showing satisfactory results in obtaining ethanol from hydrothermal pretreated SCB. However, high concentration of substrate loading favored SHF process to operate separately enzymatic hydrolysis and fermentation. This configuration achieved high ethanol yields in the conditions assessed in this work. / O bagaço de cana-de-açúcar (BCA) é um subproduto gerado após a moagem da cana-deaçúcar no processo de produção de açúcar e/ou etanol. No presente trabalho, o BCA pré-tratado foi utilizado em diferentes configurações de hidrólise enzimática e fermentação com o objetivo de obter a maior quantidade de açúcares fermentescíveis na sacarificação e convertê-los a etanol. O BCA foi pré-tratado hidrotermicamente na proporção 1:10 (m/v) nas condições 170 °C/15 min, 195 °C/10 min e 195 °C/60 min com agitação de 200 rpm. A etapa de deslignificação do BCA prétratado hidrotermicamente foi realizada com 0,02 e 0,5% de solução de NaOH na proporção 1:10 (m/v). Amostras de BCA pré-tratada e não tratada foram caracterizadas quimicamente e morfologicamente. Os primeiros ensaios de hidrólise enzimática e fermentação foram realizados na configuração PSSF (pré-sacarificação e fermentação simultâneas). Na melhor condição (10% de BCA tratado a 195 °C/10 min) foi obtido rendimento em etanol de 57,5%. Os experimentos de SSF (sacarificação e fermentação simultâneas) foram realizados em frascos de Erlenmeyers com agitação de 250 rpm a 37 °C com levedura Saccharomyces cerevisiae comercial por 72 h. Nos primeiros ensaios avaliou-se o efeito do meio inicial tamponado e não tamponado para os BCAs pré-tratados hidrotermicamente. No melhor resultado obteve-se 53,8% de conversão enzimática e concentração de etanol de 17,1 g/L (BCA tratado a 195 °C/10 min em meio tamponado. Nos ensaios seguintes, avaliou-se o efeito da carga de sólidos (10 e 15%) para amostras de BCA deslignificada e não deslignificada utilizando carga enzimática de 20 FPU/g BCA tratado. Nesses ensaios obteve-se máximos rendimentos em etanol de 53,8 e 60,0% e concentrações de etanol 17,1 e 28,4 g/L com 10 e 15% de BCA, respectivamente. Esses resultados mostraram que o aumento na carga de sólidos favoreceu o aumento no rendimento em etanol. Nos ensaios em configuração SHF (sacarificação e fermentação separadas) utilizando amostras de BCA deslignificada e não deslignificada obteve-se concentração de etanol de 39,9 g/L e rendimento em etanol de 84,0% com 15% de sólidos em 72 h. Ensaios nas configurações 10% BCA/15 FPU/g BCA tratado, 10% BCA/30 FPU/g BCA tratado, 15% BCA/15 FPU/g BCA tratado e 15% BCA/30 FPU/g BCA tratado foram realizados empregando as leveduras Kluyveromyces marxianus IMB3 e Saccharomyces cerevisiae D5A na produção de etanol a partir do BCA pré-tratado hidrotermicamente. Os resultados mostraram conversão enzimática de 64,3% e concentração máxima de etanol de 29,2 g/L utilizando 15% de sólidos em 72 h para IMB3. Para a levedura D5A obteve-se rendimento em etanol de 76,2% e a máxima concentração de etanol de 42,6 g/L em 120 h utilizando 15% de sólidos e 30 FPU/g BCA tratado. De modo geral, todas as condições avaliadas apresentaram resultados satisfatórios na obtenção de etanol a partir do BCA pré-tratado hidrotermicamente. Entretanto, cargas de substrato maiores favoreceram a configuração SHF por operar separadamente a hidrólise enzimática e a fermentação alcançando maiores rendimento em etanol nas condições avaliadas nesse trabalho.
|
47 |
Modernización de la red de acceso de un operador móvil para el caso de Lima MetropolitanaOtárola Correa, Diego Antonio, Campos Gonzales, Frank January 2015 (has links)
La presente tesina titulada “Modernización de la red de acceso de un operador móvil para el caso de Lima Metropolitana” expone una propuesta para un operador que tiene como objetivo poder incrementar su cobertura de servicio de segunda y cuarta generación, para esto se definen conceptos teóricos en base a lo que son las tecnologías de telefonía móvil celular de tipo GSM, UMTS y LTE y se compararan con las características técnicas de los equipos que se plantean usar demostrándose que estos pueden optimizar la red de acceso del operador en cobertura y funcionamiento para brindar un mejor servicio en base a 2G y 4G. Para lograr el objetivo propuesto, esta tesina describe el diseño y dimensionamiento de proyecto, pasos para su ejecución, especificaciones técnicas de los equipos, procedimiento para la puesta en servicio y resultados en base a pruebas del servicio y KPI.
The current thesis entitled “Modernización de la red de acceso de un operador móvil para el caso de Lima Metropolitana” exposes a proposal for a mobile operator that has as a target increase their second and fourth generator coverage. For achieve this we have to defined theoric concepts based on the mobile telecommunication technology GSM, UMTS and LTE and compare with the features of equipment proposed to use proving that the coverage and performance of the access network of the operator can be improved for provide a better 2G and 4G service. For achieve this target proposed, this thesis describes the design and sizing of Project, steps for execution, technical features of equipment, on air procedure and results base on the testing service and KPI.
|
48 |
Návrh postupu výroby součástí pro váleček pásového dopravníku / Proposal of the manufacturing procedure for the parts of belt conveyor rollerPavelek, Michal January 2011 (has links)
The project, which has been elaborated within the framework of Master's Degree in Manufacturing Technology (2303T002), processes a technology proposal for the production of stamped part čelo from DD14 material, with a thickness 4 mm, with production quantities of 100 000 pieces per year, in cooperation with the company UNIRON Ltd. Based on the literature study of deep drawing without thinning of the walls and calculations, production of the part of simple single-function drawing tools was proposed. The first three operations performed on a PYE 100 S/1 hydraulic press and the last calibration operation carried out on a LEK 250 eccentric press. The semi-finished product is blank with a diameter of 195 mm, produced in a simple cutting die. The cutting die is designed for both the material in the form of a sheet metal strip in coils and cut strips of metal sheet, which is associated with the use of two eccentric presses of the LEK 250 and LE 400C types. The proposed manufacturing process was simulated in the PAM-Stamp 2G software, in which the influence of the radius the functional parts of tools to change the thickness of the material is further simulated. The part of the project is a technical and economic evaluation, in which the price of one piece of the product and production quantity at which production becomes profitable was rated.
|
49 |
Innovative Marketing Trends as a Response to the Changing Consumers / Innovative Marketing Trends as a Response to the Changing ConsumersKeskin, Kaan January 2012 (has links)
In recent years, innovation and the subsequent technological advancements have gained significance in shaping consumer behavior to a disruptive extent. Especially with the advancements in mobile technology, consumer behaviors shifted towards an elevated expectation of mobility and increased interactivity. Marketers who seek a better degree of access to the consumer market and provide customer satisfaction needed to adopt new tools and methods in communication, which would align with their target groups more effectively. Mobile marketing emerged as an innovative technique that is based on and driven by this change in consumer behavior; therefore it is necessary to evaluate the effectiveness of its approach and implementation. In this light, this research paper employs a quantitative approach based on the results' analysis of an online survey conducted by the Author of the thesis, aimed at testing whether there is a strong correlation between mobile marketing efforts and customer satisfaction. Consequently, one can conclude that the same mobile devices that serve as convenience for consumers, serve as an effective channel of communication for marketers, whereas with an integrated approach where other components of the marketing mix support mobile content, the likeliness of attaining consumer satisfaction is higher.
|
50 |
藥業經營者面對二代健保實施的因應措施 / The Counter Strategies of Pharmaceuticals Leaders Address to the Implementation of 2nd Generation National Health陳光冠 Unknown Date (has links)
全民健康保險自1995年三月實施,提昇國人健康及疾病治療水準,有其正面的貢獻,但也影響了醫療相關的從業者甚巨。藥品的費用占率約全部健保費用的百分之二十五,是除了醫事服務相關費用之外,占率最高的費用。健康保險局,收支潛在的赤字在健保實施次年後已浮現,隨即採用多種藥費及藥價控管措施。新藥核價過低、過程耗時;已上市的藥品,除每兩年健保局的藥價調查後的全面性調降,和不定時的異常品項調查外,尚需面臨客戶端再次降價的要求。對於藥業營運已有顯著的負面影響。
再者現行的健保制度,保證醫療院所藥品的申報一律為健保給付價,無論其以多低的價格採購,中間的價差利潤皆歸之所有,俗稱藥價黑洞,外界難以了解其對醫療體系的運作的重要性,一味的譴責之!事實上於現行總額給付實施之下,可彌補醫療院所健保給付不足所造成的營運困難,使民眾得以持績享受價平質佳的醫療照護。然負面影響為無法提昇病患痊癒效率,也對醫事人員專業的養成,及産業的發展伏下隱憂。健保制度沿於現有的法源,法源不改,扭曲的現象續存,最終的受害者為全體民眾。
二代健保法於2011年元月立法院三讀通過。產業環境的遊戲規則勢必改變。經由訪談,二十家不同類型的藥品供應廠商的經營領導者,於新的健保法實施之際的應變措施,且其合計市占率已超過整體藥品市場的41 %。由深度訪談中,可了解不同類型的廠商,對新制度的看法及其因應措拖的異同,再佐以近代管理學的概念檢視對照不同的領導風格,推估其和產業的特性及未來發展生存之道的關連性,或許可提供予産業長遠發展的建議。
歸納本研究的重要結論為:台灣藥業環境變動是漸進的,易被輕忽影響度;且從事藥業廠商者眾不易形成共識,很難共同努力改善環境不利的變動;依靠新産品的開發取得,是藥業重要成長的策略。於經營者的研究結論:發現大多數的領導者的强項為執行力及銷售力,這可能和産品生命週期長,進入門檻高有關;但因之不利改變慣例,跳脱舒適圈,將公司導向更兼具靈活彈性又與環境更符合的營運模式。未來成長的契機在於領導者洞悉未來的趨勢;藥業營造有利趨勢,在於跳脱近親繁殖,取法於外。 / National Health Insurance has been launched on March, 1995. It has been recognized as the safeguard to the improvement for all country’s residents. The financial burden of BNHI has struggled to balance its books from early on. Drug costs contributed about 25% of NHI healthcare spending, therefore is controlled mainly through pricing and reimbursement policy, particularly the regular rounds of price cut.
The current system allows health providers gain profit from drug purchasing under negotiations with pharmaceutical companies which subsidizes the insufficient reimbursement for other service to patients. All these system hamper the healthcare industry sound growth. Without healthcare reform cannot correct the system toward healthier operation.
Winder reform in the shape of 2G NHI Act was finally passed by the Legislative Yuan in January 2011. The future NHI scheme will change in many areas. In order to understand the counter actions from pharmaceutical industry, the study is designed to interview 20 leaders in Rx companies which included different types such as MNC, domestic and agencies. The overall revenue from the 20 companies shared over 41% in Taiwan pharmaceutical industry. The study will compare and analyze the difference from each company’s actions toward the future change, from results to use modern business scholarship theory checking any particular similarity within the industry.
The main findings of the study are 1) The change of environment is easily been neglected for moving slowly and gradually, 2) To shape environment toward the positive side is difficult since hard to have consensus within industry, 3) Introduction of new products is the main growth strategy, 4) The most strength leadership capability from the interviewees is the execution, and the possible explanations are longer products life cycle plus higher entry barriers from new competitors. The downside of this type of leadership is hard to flexibly move fast in developing new business model to match the environment evolution. In-depth understanding trend of leaders will be the key of future success. The industry might learn from other industries to shape the environment more effectively.
|
Page generated in 0.0267 seconds