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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.
721

Incorporation d'azote et stabilité des polytypes de la croissance en phase gazeuse de monocristaux de SiC / Nitrogen incorporation and polytype stability of SiC single crystal growth from the vapor phase

Tsavdaris, Nikolaos 06 January 2015 (has links)
Le carbure de silicium est l'un des semi-conducteurs les plus importants et les plus répandus dans les appareils électroniques de puissance. Du fait de la demande croissante d'électronique à haut rendement, bas coût et économe en énergie, il est nécessaire d'améliorer les propriétés des semi-conducteurs monocristallins. Cela demande une meilleure compréhension des phénomènes impliqués dans le procédé de croissance de ces matériaux. Cette thèse présentera de nouvelles perspectives sur deux sujets majeurs dans le domaine de la croissance en phase gazeuse de monocristaux de SiC. Dans un premier temps, le procédé de croissance utilisé dans notre laboratoire a été développé dans le but d'améliorer la qualité et la taille des cristaux de SiC obtenus. Une géométrie permettant la croissance sans contact et reproductible de monocristaux de SiC a été obtenue. La nucléation et la propagation des instabilités structurelles (inclusions de polytype étranger) apparaissant lors de la croissance ont été étudiés de façon continue. Deux critères spécifiques doivent être réunis pour qu'un polytype étranger puisse nucléer. Une fois le point de nucléation localisé, la propagation du polytype étranger dans le volume du cristal peut être appréhendée. Lorsque la stabilisation et déstabilisation des polytypes de SiC ont été mieux comprises, une tentative a été faite pour stabiliser la croissance du polytype 15R-SiC. L'objectif final, les paramètres de croissance susceptibles de renforcer la croissance préférentielle de 15R-SiC, a été mis en évidence. Enfin, l'incorporation d'azote pendant la croissance en phase gazeuse de monocristaux a été étudiée. En effet, aucune description détaillée n'existe pour l'incorporation d'azote dans le SiC, bien que ce soit le dopant le plus couramment utilisé. Notre contribution à cet effort porte sur l'étude de la concentration d'azote dans les cristaux obtenus en fonction de différents paramètres de croissance. Compte tenu des mécanismes d'adsorption/désorption à la surface de croissance, un effort a été fait pour expliquer les tendances obtenues expérimentalement. / Silicon Carbide is one of the most important and widely used semiconductors for power electronic devices. Due to the increasing demand for high efficiency, low cost and energy saving electronics, further improvement of the properties of single crystal semiconductors is needed. That requires a better understanding of the phenomena involved in the growth process of these materials. This thesis will bring some new insight into two main topics at the field of SiC bulk growth from the vapor phase. Initially, the growth process used in our laboratory was developed in order to improve the quality and the size of the grown SiC crystal. A geometry that allows the contactless and reproducible growth of SiC single crystals was obtained. Continuously, we investigated the nucleation and propagation of structural instabilities (foreign polytype inclusions) that appear during growth. Two specific criteria must be fulfilled for a foreign polytype to be nucleated. Once the nucleation point is located, the propagation of the foreign polytype in the volume of the grown crystal can be comprehended. Once the stabilization or destabilization of the SiC polytypes was better perceived, an attempt was made to stabilize the growth of the 15R-SiC polytype. As a final objective, the growth parameters that could preferentially enhance the growth of the 15R-SiC are highlighted. Last, nitrogen incorporation during bulk growth from the vapor phase was studied. Indeed as the most commonly used dopant, no full description exists for the incorporation of nitrogen in SiC. We contribute to this effort by exploring the nitrogen concentration in the grown crystals as a function of various growth parameters. Considering the adsorption/desorption mechanisms at the growing surface, effort was given to explain the experimentally obtained trends.
722

Ultraviolet emitters grown by metalorganic chemical vapor deposition

Liu, Yuh-Shiuan 13 January 2014 (has links)
This thesis presents the development of III-nitride materials for deep-ultraviolet (DUV) light emitting devices. The goal of this research is to develop a DUV laser diode (LD) operating at room temperature. Epitaxial structures for these devices are grown by metalorganic chemical vapor deposition (MOCVD) and several material analysis techniques were employed to characterize these structures such as atomic force microscopy, electroluminescence, Hall-effect measurement, photoluminescence, secondary ion mass spectrometry, transmission electron microscopy, transmission line measurement, and X-ray diffraction. Each of these will be discussed in detail. The active regions of III-nitride based UV emitters are composed of AlxGa1-xN alloys, the bandgap of which can be tuned from 3.4 eV to 6.2 eV, which allows us to attain the desired wavelength in the DUV by engineering the molar fraction of aluminum and gallium. In order to emit photons in the DUV wavelength range (> 4.1 eV), high aluminum molar fraction AlxGa1-xN alloys are required. Since aluminum has very low ad-atom mobility on the growth surface, a very low group V to group III precursor ratio (known as V/III ratio), high growth temperature, and low growth pressure is required to form a smooth surface and subsequently abrupt heterointerfaces. The first part of this work focuses on developing high-quality multi-quantum well structures using high aluminum molar fraction ([Al] > 60%) AlxGa1-xN alloys. Optically pumped DUV lasers were demonstrated with threshold power density as low as 250 kW/cm² for the emission wavelength as short as 248.3 nm. Transverse electric (TE) -like emission dominates when the lasers were operating above threshold power density, which suggests the diode design requires the active region to be fully strained to promote better confinement of the optical mode in transverse direction. The second phase of this project is to achieve an electrically driven injection diode laser. Owing to their large bandgap, low intrinsic carrier concentration, and relatively high dopant activation energy, the nature of these high aluminum molar fraction materials are highly insulating; therefore, efficiently transport carriers into active region is one of the main challenges. Highly conducting p-type material is especially difficult to achieve because the activation energy for magnesium, a typical dopant, is relatively large and some of the acceptors are compensated by the hydrogen during the growth. Furthermore, due to the lack of a large work function material to form a p-type ohmic contact, the p-contact layer design is limited to low aluminum molar fraction material or gallium nitride. Besides the fabrication challenges, these low aluminum molar fraction materials are not transparent to the laser wavelength causing relatively high internal loss (αi). In this work, an inverse tapered p-waveguide design is employed to transport holes to active region efficiently while the graded-index separate-confinement heterostructure (GRINSCH) is employed for the active region design. Together, a multi-quantum well (MQW) ultraviolet emitter was demonstrated.
723

Steps toward the creation of a carbon nanotube single electron transistor

Ferguson, R. Matthew 07 May 2003 (has links)
This report details work toward the fabrication of a single-electron transistor created from a single-walled carbon nanotube (SWNT). Specifically discussed is a method for growing carbon nanotubes (CNTs) via carbon vapor deposition (CVD). The growth is catalyzed by a solution of 0.02g Fe(NO3)3·9H2O, 0.005g MoO2(acac)2, and 0.015g of alumina particles in 15mL methanol. SWNT diameter ranges from 0.6 to 3.0 nm. Also discussed is a method to control nanotube growth location by patterning samples with small islands of catalyst. A novel “maskless” photolithographic process is used to focus light from a lightweight commercial digital projector through a microscope. Catalyst islands created by this method are approximately 400 μm2 in area.
724

Controle multivariável aplicado a uma coluna de alta pureza com recompressão de vapor.

EMERENCIANO, Mariângela da Silva Araújo. 02 February 2018 (has links)
Submitted by Gustavo Nascimento (gustavo.diniz@ufcg.edu.br) on 2018-02-02T12:22:34Z No. of bitstreams: 1 MARIÂNGELA DA SILVA ARAÚJO EMERENCIANO - TESE PPGEQ 2014.pdf: 2549347 bytes, checksum: 4f7d187e940acf4a6dcad840f1d5c392 (MD5) / Made available in DSpace on 2018-02-02T12:22:34Z (GMT). No. of bitstreams: 1 MARIÂNGELA DA SILVA ARAÚJO EMERENCIANO - TESE PPGEQ 2014.pdf: 2549347 bytes, checksum: 4f7d187e940acf4a6dcad840f1d5c392 (MD5) Previous issue date: 2014-12-17 / Capes / Os processos industriais são sistemas multivariáveis (MIMO) que consistem de múltiplas variáveis de entrada e múltiplas variáveis de saída, onde a interação entre essas variáveis é uma característica inerente desses processos. A identificação do modelo nesse tipo de processo é uma etapa importante na implementação do sistema de controle, principalmente quando se trata de controladores MPC, os quais incorporam um modelo explícito do processo. O procedimento de identificação realizado neste trabalho propõe uma abordagem diferente da que se tem visto na literatura. Enquanto o mais comum é estimular as variáveis manipuladas, a nova abordagem proposta visa estimular o processo a partir de perturbações nos setpoints das variáveis controladas, em malha fechada, com o intuito de se obter uma melhor avaliação dos efeitos das variáveis controladas e manipuladas. A proposta deste trabalho é comparar duas estratégias de controle: uma estratégia de controle clássico e uma estratégia de controle multivariável baseado em modelo (MPC). O estudo de caso é uma coluna de separação propeno/propano de alta pureza com recompressão de vapor. Quando comparado o controle descentralizado com o controle MPC, observa-se que o MPC apresenta melhores resultados, afirmação esta, baseada nos valores do índice de desempenho IAE (Integral Absolute Error) para as duas propostas analisadas. / Industrial processes are multivariable systems (MIMO) consisting of multiple input variables and multiple output variables, where the interaction between these variables is an inherent characteristic of these processes. The model identification in this type of process is an important step in the implementation of the control system, especially when it comes to MPC controllers, which incorporate an explicit process model. The identification procedure performed in this research proposes a different approach to what has been seen in the literature. While the most common is to stimulate the manipulated variables, the proposed new approach aims to stimulate the process from disturbances in the setpoints of the controlled variables, closed loop, in order to obtain a better assessment of the effects of controlled and manipulated variables. The purpose of this study is to compare two control strategies: A classic control strategy and a multivariable control strategy based on model (MPC). The case study is a column separation of propylene / propane with high purity vapor recompression. When compared with the decentralized control the MPC control, it is observed that the MPC performs better, this statement, based on the values of IAE performance index (Integral Absolute Error) for the two proposals analyzed.
725

Análise da variabilidade espaço-temporal da água precipitável na atmosfera utilizando dados do ERA– INTERIM/ECMWF.

CABRAL, Danilo Ericksen Costa. 27 August 2018 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-08-27T15:03:16Z No. of bitstreams: 1 DANILO ERICKSEN COSTA CABRAL – DISSERTAÇÃO (PPGMET) 2018.pdf: 3103151 bytes, checksum: 21c39f5e775ca2cffae4904318258171 (MD5) / Made available in DSpace on 2018-08-27T15:03:16Z (GMT). No. of bitstreams: 1 DANILO ERICKSEN COSTA CABRAL – DISSERTAÇÃO (PPGMET) 2018.pdf: 3103151 bytes, checksum: 21c39f5e775ca2cffae4904318258171 (MD5) Previous issue date: 2017-12-22 / Analisou-se neste estudo a tendência anual e a média global da Água Precipitável (AP) no período de 1986 a 2016. Foram utilizados dados extraídos das reanálises do ERAInterim/ European Center for Medium-Range Weather Forecasts (ECMWF). A partir destes dados avaliou-se a distribuição espacial da tendência de Água Precipitável. Para a análise da tendência climática aplicou-se testes estatísticos de Mann-Kendall e t de Student observandose o comportamento das séries globais. Para a variável AP, foi encontrado o valor médio de 24,4mm para todo o período, correspondendo a um volume estimado para toda a atmosfera. Os resultados apontam tendências significativas de 0,0246; 0,0121 e 0,0203 mm/ano para o HN; HS e todo o Globo, respectivamente. Foi observada uma tendência positiva para algumas áreas do globo bem como outras negativas, resultando em uma distribuição não homogênea, denotando-se uma provável tendência de aumento do vapor d’água no globo. / In this study was analyzed the annual trend and the global mean of Precipitation Water (WP) from 1986 to 2016. Data extracted from the ERA-Interim / European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis were used. From these data was evaluated the Precipitation Water tendency spatial distribution. For the analysis of the climatic trend, Mann-Kendall and t-Student statistical tests were applied, observing the behavior of the global series. For the WP variable was found the average value of 24.4 mm for the whole period, corresponding to estimated volume for the whole atmosphere. The results indicate significant trends of 0.0246, 0.0121 and 0.0203 mm /year for HN; HS and the whole Globe, respectively. A positive trend was observed for some areas of globe as well as negative values, resulting the not homogeneous distribution, denoting a probable tendency to increase water vapor in the globe.
726

Preparação da zeólita ferrierita pelo método de transporte em fase vapor / Preparation of zeolite ferrierite by method vapor-phase transport

Modesto Neto, Pedro Paulo 02 September 2011 (has links)
Ferrierite zeolite has a specific crystalline structure that gives unique catalytic properties that enable the selective isomerization of n-butene to isobutene and selective cracking of n-paraffins in the range of gasoline, mainly producing light olefins (ethylene and propylene). This study focused on assessing the formation and crystal growth method of transport through vapor phase (VTP) for fixed conditions of temperature, Si / Al and time of crystallization. In the work variables were used: structural directors, source of aluminum and % seeds. The experiments showed synthesis for transport method in phase steam with addition of seeds presented satisfactory results. Most of the samples synthesized in the work exhibited high crystalline percentage, with superior values to 90%, when compared with the commercial pattern. The results of crystalline percentage of synthesized materials indicated that there is an outstanding influence of the source of aluminum (sulfate of aluminum or pseudoboehmite) about the crystallization of the ferrierite zeolite for the transport method in vapor phase in the pyrrolidine presence as organic director, however when the director is the ethylenediamine this fact is almost imperceptible. / Fundação de Amparo a Pesquisa do Estado de Alagoas / A zeólita ferrierita apresenta uma estrutura cristalina específica que lhe confere propriedades catalíticas únicas, que possibilitam a isomerização seletiva de n-buteno em isobuteno e o craqueamento seletivo de n-parafinas, na faixa da gasolina, produzindo principalmente olefinas leves (eteno e propeno). O presente trabalho dirigi-se a avaliação da formação e crescimento cristalino através do método de transporte de fase vapor (VTP), para condições fixas de temperatura, razão de Si/Al e tempo de cristalização. No trabalho foram utilizadas as variáveis: direcionadores estruturais, fonte de alumínio e teor de sementes. Os experimentos mostraram que a síntese pelo método de transporte em fase vapor com a adição de sementes apresentaram resultados satisfatórios. A maioria das amostras sintetizadas no trabalho exibiu alta percentagem de cristalinidade, com valores superiores a 90%, quando comparados com o padrão comercial. Os resultados de cristalinidade dos materiais sintetizados indicaram que há uma influência marcante da fonte de alumínio (sulfato de alumínio ou pseudobohemita) sobre a cristalização da zeólita ferrierita pelo método de transporte em fase vapor na presença de pirrolidina como direcionador orgânico, contudo quando o direcionador é a etilenodiamina este feito é quase imperceptível.
727

Characterization of Cubic Boron Nitride Interfaces with in situ Photoelectron Spectroscopy

January 2016 (has links)
abstract: Cubic boron nitride (c-BN) has potential for electronic applications as an electron emitter and serving as a base material for diodes, transistors, etc. However, there has been limited research on c-BN reported, and many of the electronic properties of c-BN and c-BN interfaces have yet to be reported. This dissertation focused on probing thin film c-BN deposited via plasma enhanced chemical vapor deposition (PECVD) with in situ photoelectron spectroscopy (PES). PES measurements were used to characterize the electronic properties of c-BN films and interfaces with vacuum and diamond. First, the interface between c-BN and vacuum were characterized with ultraviolet PES (UPS). UPS measurements indicated that as-deposited c-BN, H2 plasma treated c-BN, and annealed c-BN post H2 plasma treatment exhibited negative electron affinity surfaces. A dipole model suggested dipoles from H-terminated N surface sites were found to be responsible for the NEA surface. Then, Si was introduced into c-BN films to realize n-type doped c-BN. The valence structure and work function of c-BN:Si films were characterized with XPS and UPS measurements. Measurements were unable to confirm n-type character, and it is concluded that silicon nitride formation was the primary effect for the observations. Finally, XPS measurements were employed to measure the band offsets at the c-BN/diamond interface. Measurements indicated the valence band maximum (VBM) of c-BN was positioned ~0.8 eV above the VBM of diamond. / Dissertation/Thesis / Doctoral Dissertation Physics 2016
728

Otimização de uma unidade de destilação de solvente.

BATISTA, Rodrigo Albuquerque. 26 July 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-07-26T20:04:29Z No. of bitstreams: 1 RODRIGO ALBUQUERQUE BATISTA – DISSERTAÇÃO (PPGEQ) 2009.pdf: 1371116 bytes, checksum: e83cb01217e145c19452e17728123ea0 (MD5) / Made available in DSpace on 2018-07-26T20:04:29Z (GMT). No. of bitstreams: 1 RODRIGO ALBUQUERQUE BATISTA – DISSERTAÇÃO (PPGEQ) 2009.pdf: 1371116 bytes, checksum: e83cb01217e145c19452e17728123ea0 (MD5) Previous issue date: 2009-03-31 / A destilação é um dos processos de separação mais importantes e que também, mais consomem energia em indústrias químicas e petroquímicas. Portanto sua operação otimizada é condição sine qua non para viabilidade dos negócios. Além do alto consumo, em alguns processos ocorre a formação de compostos azeotrópicos que se mantêm presentes na destilação; estes se classificam entre homogêneos e heterogêneos. Este trabalho abordou a otimização do sistema de purificação de solvente (trem de destilação) de uma das unidades da Braskem, o qual é constituído por duas colunas de destilação e um vaso de flash. A planta onde está localizado o sistema de purificação produz polietilenos de Alta Densidade (PEAD) e de Ultra Alto peso Molecular (PEUAPM) através da tecnologia Slurry. A polimerização é realizada em suspensão de solvente e utiliza reatores do tipo mistura perfeita (CSTR). A perda de solvente e o consumo de vapor representam 80% do custo variável após matérias primas da planta de produção de polietileno de alta densidade tecnologia slurry da MCI – Mitsubishi Chemical Inc. A otimização das colunas de destilação da Planta PE2 da Braskem utilizando modelo termodinâmico de Peng Robinson através do simulador comercial Aspen Plus demonstrou potencial de economia de 1.200.000 R$/ano. / The distillation is the most important separation process in chemical engineer, on the other hand it is the highest industry energy consumer. Therefore, optimized operation is essential to business feasibility. In some process happen the azeotropic moisture is formed that is hold in the distillation section, they can be classified as homogeneous or heterogeneous. This work approached the optimization of the Solvent Purification System (distillation train) from Braskem PE2 unit who is built up from to two distillation columns and one flash drum. The PE2 unit who produce High Density Polyethylene and Ultra High Molecular Weight Polyethylene by slurry process from Mitsubishi Chemical Corporation is localized in Camacari, Brazil. The polymerization is conduced in a solvent suspension and use Continuous Stirred Tank Reactor (CSTR) type. The solvent lost and the steam consumer together the 80% from the variable cost, before raw material, in High Densit y Polyethylene and Ultra High Molecular Weight Polyethylene by slurry process from Mitsubishi Chemical Corporation. The optimization from Braskem PE2 Unit distillation system, using thermodynamic model Peng Robinson through the Aspen Plus commercial simulator presented 1.200.000 R$/y.
729

Efetividade de corte das pontas do sistema CVDentUS : estudo in vitro /

Lima, Luciana Monti. January 2003 (has links)
Orientador: Lourdes Aparecida Martins dos Santos-Pinto / Banca: Evaldo José Corat / Banca: Celso Luiz de Angelis Porto / Resumo: A tecnologia CVD (Chemical Vapor Deposition) aplicada à confecção de pontas odontológicas diamantadas possibilitou aderência do diamante à haste metálica suficiente para suportar o efeito do ultra-som, surgindo então uma técnica alternativa para corte de tecido dentário. O objetivo deste estudo in vitro foi avaliar a efetividade dos corte realizados com as pontas CVD cilíndrica e esférica para ultra-som (pontas CVDentUSÒ), em esmalte e dentina de dentes permanentes, variando-se o sentido de movimento (frontal e lateral). Foram utilizados 40 terceiros molares, num total de 80 preparos cavitários confeccionados por meio de um dispositivo padronizador. Os cortes foram realizados com 30 movimentos consecutivos da ponta sobre a superfície dentária, correspondendo a 27 segundos de utilização das pontas CVDentUSÒ. A profundidade e largura dos preparos cavitários foram analisadas em microscopia eletrônica de varredura e medidas por meio de uma análise cefalométrica modificada no programa Radiocef 4.0 (Radiocef Memory Ltda). A análise estatística pelo teste não paramétrico de Kruskal-Wallis ao nível de significância de 5% mostrou que as maiores médias de largura e profundidade foram observadas nos preparos de dentina, sendo a ponta esférica responsável por cavidades mais profundas e a cilíndrica por cavidades mais largas, não havendo influência dos sentidos de movimento da ponta. / Abstract: The CVD (Chemical Vapor Deposition) technology applied in dental diamond burs manufacture allowed to the diamond to have enough adherence to the metallic stem supporting the ultrasound effect. This technique is bringing back an alternative method to cut dental tissue. The aim of this in vitro study was to evaluate the cutting effectiveness of cylindrical and round CVD-coated diamond burs for ultrasound (CVDentUSÒ system), in enamel and dentine of permanent teeth, changing the movement sense (frontal and lateral). Forty third molars were used, in a total of 80 cavity preparations made using a standard device. The cuts were made with 30 consecutive movements of the bur on the dental surface, corresponding to 27 seconds of CVDentUSÒ tips use. The depth and width of the cavity preparations were analyzed by scanning electronic microscopy and the measures were made using a modified cefalometric analysis in a Radiocef 4.0 program (Radiocef Memory Ltda). The statistical analysis applying Kruskal-Wallis non-parametric test, at 5% significance level, showed that the largest width and depth averages were observed in dentine cavities, being the round bur responsible for deeper cavities and the cylindrical for wider cavities. The movement senses had no influence on cavity size. / Mestre
730

IncorporaÃÃo de Ãleo essencial de manjericÃo em filmes biodegradÃveis à base de galactomanana e Ãleo de canola / Essential oil of basil incorporation into biodegradable films galactomannan base and canola oil

Rosueti DiÃgenes de Oliveira Filho 12 August 2015 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Embalagens biodegradÃveis sÃo coberturas utilizadas em alimentos na forma de filmes ou revestimentos, formadas por macromolÃculas tanto de origem vegetal como de origem animal, que garantem propriedades de barreira e podem servir como veÃculo para compostos antimicrobianos. Os polissacarÃdeos de reserva de parede celular, principalmente as hemiceluloses como as galactomananas, vÃm sendo extensamente usadas como matrizes polimÃricas de filmes biodegradÃveis. O objetivo deste trabalho foi avaliar a incorporaÃÃo de Ãleo essencial de manjericÃo (OEM) (Ocimum basilicum) em filmes biodegradÃveis à base de galactomanana endospÃrmica de sementes de flamboyant (Delonix regia) e Ãleo canola (OC) (Brassica napus L.). A Galactomanana (Gal) foi isolada por extraÃÃo aquosa, seguida por precipitaÃÃo em etanol. O rendimento determinado foi de 12,0%, com alto grau de pureza apresentado pelo baixo teor de nitrogÃnio expresso em proteÃna (0,67%). A Gal apresentou viscosidade intrÃnseca mÃdia de 3,79 dL/g e massa molar estimada de 1,04x106 g/mol. Os espectros de infravermelho por transformada de Fourier (FTIR) e ressonÃncia magnÃtica nuclear (RMN) de 1H e 13C foram similares aos encontrados na literatura para outras galactomananas. A composiÃÃo em Ãcidos graxos do OC por cromatografia a gÃs (GC-FID) apresentou teores de Ãcido oleico (62,07%), linoleico (18,91%) e heneicosanÃico (6,61%). Os componentes majoritÃrios do OEM determinados por cromatografia a gÃs acoplado à espectrometria de massas (GC-MS) foram cÃnfora (14,85%) e 1,8-cineol (3,48%). Os filmes foram formulados com Gal 1% (m/v), glicerol 0,5% (m/v) e OC em diferentes concentraÃÃes, 0,25, 0,5 e 0,75% (m/v). Os filmes foram obtidos pelo mÃtodo de evaporaÃÃo de solvente (casting) e caracterizados quanto ao teor de umidade, espessura, permeabilidade ao vapor de Ãgua (PVA), cor e opacidade. O OC promoveu aumento de PVA e diminuiÃÃo do teor de umidade quando comparado ao filme apenas de galactomanana, mas sem diferenÃa significativa entre as concentraÃÃes. O OEM foi testado frente Ãs cepas bacterianas de Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella choleraesuis, Staphylococcus aureus e levedura Candida albicans por microdiluiÃÃo em caldo e apresentou concentraÃÃo inibitÃria mÃnima (CIM) variando entre 2,5 e 5,0 mg/mL e concentraÃÃo bactericida mÃnima (CBM) entre 5,0 e 20,0 mg/mL. A partir do filme com formulaÃÃo de 0,5 % (m/v) de OC incorporou-se OEM em diferentes concentraÃÃes (2,5, 5,0 e 7,5 mg/mL). Os filmes antimicrobianos foram obtidos por casting e discos de 1 cm de diÃmetro foram excisados e testados por mÃtodo de difusÃo em Ãgar e a zona de contato e os halos de inibiÃÃo analisados. S. aureus, E. coli e P. aeruginosa foram sensÃveis ao filme contendo 5,0 mg/mL de OEM apresentando halos de 14, 15 e 16,3 mm, respectivamente. K. pneumoniae foi inibida apenas na zona de contato do filme, enquanto que S. choleraesuis e C. albicans foram resistentes à todas as formulaÃÃes. Contudo, O OC promoveu alteraÃÃes nas propriedades fÃsicas e de barreira dos filmes de galactomanana e OEM quando incorporado ao filme apresentou uma atividade antimicrobiana moderada para potencial aplicaÃÃo como embalagens bioativas. / Biodegradable Packaging are used in foods as films or coatings formed by plant macromolecules such as animal, ensuring barrier properties and can serve as a carrier for antimicrobial compounds. The cell wall polysaccharides reservation, especially hemicelluloses as galactomannans, have been used widely as biodegradable polymer matrices films. The objective of this study was to evaluate the Basil essential oil (BEO) (Ocimum basilicum) incorporation in biodegradable films based on endospermic galactomannan Delonix regia seeds and canola oil (CO) (Brassica napus L.). The galactomannan (Gal) was isolated by aqueous extraction, followed by ethanol precipitation. The yield was 12.0% with high purity presented by low nitrogen content expressed protein (0.67%). The Gal showed an average intrinsic viscosity of 3.79 dL/g and molecular weight estimated in 1,04x106 g/mol. Infrared spectra by Fourier transform (FTIR) and nuclear magnetic resonance (NMR) 1H and 13C were similar to those found in the literature for other galactomannans. The fatty acid composition of CO by gas chromatography (GC-FID) showed oleic acid (62.07%), linoleic (18.91%) and heneicosanÃico (6.61%) content. The major components of BEO determined by gas chromatography coupled to mass spectrometry (GC-MS) were camphor (14.85%) and 1.8-cineole (3.48%). The films were formulated with galactomannan 1% (w/v), glycerol 0.5% (w/v) and CO at different concentrations, 0.25, 0.5 and 0.75% (w/v). The films were obtained by the solvent evaporation method (casting) and characterized as the moisture content, thickness, water vapor permeability (WVP), color and opacity. The CO promoted increase of WPV and reduced moisture content when compared to the film based only in galactomannan but no significant difference between concentrations. BEO was tested against the bacterial strains of Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella choleraesuis, Staphylococcus aureus and Candida albicans yeast by broth microdilution and showed minimum inhibitory concentration (MIC) ranging between 2.5 and 5.0 mg/ml and minimum bactericidal concentration (MBC) between 5.0 and 20.0 mg/ml. BEO was incorporated into film formulation with CO 0.5% (w/v) in different concentrations (2.5, 5.0 and 7.5 mg/ml). The antimicrobial films were obtained by casting and disks of 1 cm in diameter were excised and tested by the agar diffusion method and a contact zone and inhibition halos analyzed. S. aureus, E. coli and P. aeruginosa were sensitive to film containing BEO 5.0 mg/ml showed halos of 14, 15 and 16.3 mm, respectively. K. pneumoniae was inhibited only in the contact zone of the film, while S. choleraesuis and C. albicans were resistant to all formulations. However, the OC promoted changes in physical and barrier properties of the films of with galactomannan. BEO when incorporated into the film showed a moderate antimicrobial activity for potential application as bioactive packaging.

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