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Desempenho produtivo e composi??o do leite e da carne de caprinos alimentados com res?duo de panifica??o / Performance and composition of milk and goat meat fed with bakery wasteMORENZ, Danilo Antonio 31 May 2016 (has links)
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Previous issue date: 2016-05-31 / CAPES / The aim was evaluate the effect of replacing corn by bakery waste (BW) in goats diet on performance, dry matter and nutrients intake, carcass characteristics, chemical composition and fatty acid profile of the Longissimus dorsi muscle and the food intake, apparent digestibility, nitrogen balance, ruminal parameters, production and composition of milk by goats. Experiment 1: Four levels of inclusion of BW replacing corn (0, 33, 66, 100%) in the diet of kids distributed in a completely randomized design were analyzed. The diets were composed of concentrate and Cynodon spp. hay, with forage: concentrate ratio of 60:40. The intakes of dry matter, organic matter, crude protein, ether extract and carbohydrates decreased linearly, while the non-fiber carbohydrates intake, animal performance, carcass characteristics and chemical composition were not affected by replacement of corn by BW. The elaidic acid content (C18: 1 trans-9) increased in the fatty acid profile of the Longissimus dorsi muscle with the inclusion of RP, which can be used as a substitute for corn meal in goats feed composition. It was concluded that bakery waste can substitute the corn up to 100% in the concentrate mixture without affecting intake, performance and carcass and meat traits of kids. Experiment 2: Bakery waste was added replacing 0; 25; 50; 75 and 100% of the concentrate in dry matter basis. Five Saanen lactating goats, non-pregnant with an average weight of 55.7 kg were arranged in a 5 x 5 Latin Square design. Experimental diets were composed by Cynodon hay and concentrate, in a roughage:concentrate ration of 40:60. The inclusion of BW in diets decreases the intake of ether extract, acid detergent fiber and the coefficients of apparent digestibility of crude protein and ether extract. Different levels of substitution did not affect ruminal pH, but for the concentration of ruminal ammonia was found linear reduction with the level of replacement. The inclusion of BW in diets increased the efficiency of use of N. The bakery waste can replace conventional concentrate in diets for goats. / Objetivou-se avaliar o efeito da substitui??o do milho pelo res?duo de panifica??o (RP) na dieta de cabritos sobre o desempenho, consumo de mat?ria seca e dos nutrientes, caracter?sticas de carca?a, composi??o qu?mica e perfil dos ?cidos graxos do m?sculo Longissimus dorsi e em cabras em lacta??o o consumo alimentar, a digestibilidade aparente, o balan?o de compostos nitrogenados, os par?metros ruminais, a produ??o e a composi??o do leite. Experimento 1: Foram analisados quatro n?veis de inclus?o do RP em substitui??o ao milho (0, 33, 66, 100%) na dieta de cabritos distribu?dos em delineamento inteiramente casualizado. As dietas foram compostas de concentrado e feno de Cynodon spp, com rela??o volumoso:concentrado de 60:40. O consumo de mat?ria seca (MS), mat?ria org?nica (MO), prote?na bruta (PB), extrato et?reo (EE) e carboidratos totais (CT) foi linear decrescente, enquanto que o consumo de carboidratos n?o fibrosos (CNF), o desempenho dos animais, as caracter?sticas de carca?a e a composi??o centesimal n?o foram influenciados pela inclus?o do RP em substitui??o ao milho. O teor de ?cido ela?dico (C 18:1 trans-9) aumentou no perfil de ?cidos graxos do m?sculo Longissimus dorsi com a inclus?o do RP. Conclui-se que o RP pode substituir o milho em at? 100% na mistura do concentrado. Experimento 2: Foram avaliados cinco n?veis de substitui??o do concentrado pelo RP (0, 25, 50, 75, 100%), utilizando-se cinco cabras em lacta??o da ra?a Saanen, com peso m?dio de 55,7 kg, distribu?dos em delineamento em Quadrado Latino 5 X 5. As dietas experimentais foram compostas de concentrado e feno de Cynodon spp, numa rela??o volumoso:concentrado de 40:60 na mat?ria seca. Houve redu??o linear do consumo de EE, do consumo de FDA, da digestibilidade da PB e da digestibilidade do EE. A substitui??o crescente do concentrado pelo RP na dieta n?o influenciou o pH ruminal, por?m reduziu a concentra??o de N-NH3 no l?quido ruminal. A inclus?o do RP em n?veis crescentes nas dietas favoreceu a efici?ncia de utiliza??o de nitrog?nio. O RP pode substituir totalmente o concentrado na dieta de cabras em lacta??o.
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Uso de imagens multiespectrais de baixo custo para classificar n?veis de N aplicados ao solo em Agricultura de Precis?o / Low-cost multispectral images used to sort N levels applied to the soil in Precision Agriculture.Silva, Ramon de Souza Victorino da 18 February 2016 (has links)
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Previous issue date: 2016-02-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / The aim of this project was to develop a statistical classifier based on algorithms using
Bayesian theorem for prediction of nitrogen applied to the soil using low cost multispectral
images Tifton85 pastures From information obtained from these images the indexes were
calculated spectrum, which was used in a feature vector for discriminating N levels applied to the
soil. The research was developed in the Rural Federal University of Rio de Janeiro, Department of
Engineering, Machinery Area and Energy in Agriculture. The data were obtained from an
experiment installed in the production area of Company Feno Rio Agro LTDA, partner in the
project. Images were acquired in 2 times one after 36 days due to the cutting standardization of
culture using a UAV (Unmanned Aerial Vehicle) and at 7, 14, 21, 28, 35, 42, 56 days using an
imaging platform an experiment with 6 portions 250m2 (10x25m) containing respectively the
treatments (0, 50, 100, 150, 200 and 250 kg ha-? N), statistical analyzes were performed the
computer program SAS version student using PROCDISCRIM procedure. It was determined
discriminant functions for each dose of nitrogen, using as feature vectors vegetation indices
(NDVI, GNIR, SAVI, GNDVI, RNIR). These discriminant functions were tested in a Bayesian
classifier, and the highest accuracies were using vegetation indices together getting a Kappa
coefficient and overall accuracy of 83% and 80%, respectively. The results indicate that low cost
multispectral images can be used to develop classifiers of nitrogen applied to the soil. These
binders may be applied in computational algorithms in agricultural machinery control systems for
fertilizer application at variable rates in precision agriculture. / O objetivo geral deste projeto foi desenvolver um classificador estat?stico com base
em algoritmos utilizando o teorema bayesianos para predi??o de doses de nitrog?nio aplicadas
ao solo, atrav?s de imagens multiespectrais de baixo custo em pastagens de Tifton85 A partir
de informa??es obtidas nessas imagens foram calculados os ?ndices espectrais, os quais foram
utilizados em um vetor de caracter?sticas para discriminar n?veis de N aplicados ao solo. A
pesquisa foi desenvolvida na Universidade Federal Rural do Rio de Janeiro, Departamento de
Engenharia, ?rea de M?quinas e Energia na Agricultura. Os dados foram obtidos de um
experimento instalado no campo de produ??o da Empresa Feno Rio Agro LTDA, parceira do
projeto. As imagens foram adquiridas em 2 momentos uma ap?s 36 dias decorrentes ao corte
de uniformiza??o da cultura utilizando um VANT (Ve?culo A?reo N?o Tripulado) e aos 7, 14,
21, 28, 35, 42, 56 dias utilizando uma plataforma de capta??o de imagens de um experimento
com 6 parcelas contendo respectivamente os tratamentos (0, 50, 100, 150, 200 e 250 kg ha
-?
de N), as an?lises estat?sticas foram realizadas no programa computacional SAS vers?o
estudante, utilizando o procedimento PROCDISCRIM. Determinou-se fun??es discriminantes
para cada dose de nitrog?nio, utilizando-se como vetores de caracter?sticas os ?ndices de
vegeta??o (NDVI, GNIR, SAVI, GNDVI, RNIR). Essas fun??es discriminantes foram
testadas em um classificador bayesiano, sendo que a maior acur?cia de classifica??o foi
utilizando os ?ndices de vegeta??o em conjunto obtendo um coeficiente Kappa e a exatid?o
global de 83% e 80%, respectivamente. Os resultados indicam que imagens multiespectrais de
baixo custo podem ser utilizadas para desenvolver classificadores de doses de nitrog?nio
aplicadas ao solo. Esses classificadores poder?o ser aplicados em algoritmos computacionais
em sistemas de controle de m?quinas agr?colas para aplica??o de fertilizantes a taxas vari?veis
em agricultura de precis?o.
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Avalia??o da toler?ncia ao alum?nio em pl?ntulas de maracujazeiro e mamoeiro. / Evaluation of aluminum tolerance in seedlings of Passion fruit and Carica papaya.Silva, Aldir Carlos 06 March 2009 (has links)
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Previous issue date: 2009-03-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Aluminum tolerance studies in seedlings of Passion fruit (cvs. IAC-273/277, IACPaulista,
IAC-275, FB-100) and Carica papaya (cvs.Taiung, Golden, Gran Golden,
Baixinho de Santa Amalia) were performed in a growth chamber at the Laboratories of
Chemistry of the Rhizosphere and Seeds of the Department of Fitotecnia, of University
Federal Rural of Rio Janeiro, Institute of Agronomy. Experiments with different
concentrations of Al were conducted in nutrient solution simple (with Ca) and complete,
with the aims to analyze the tap root length, ratio of root lengths, relative root
elongation, diameter of root and stem and effect of stains. Also were conducted
experiments with seeds soaked in different concentration of Al to verify the percentage
of germination, seedlings normal and abnormal. The use of simple nutrient solution was
not satisfactory to shown the performance of seedlings of papaya. In passion fruit both
nutrient solutions can be used in short term experiment. Over the concentration of
160?M of Al occurred effect of toxicity in root of seedlings of passion fruit and papaya,
but at concentrations lower that 80?M there were stimulus of growth. The tap root
length was the more efficient parameter to compare root toxicity. The soaking of seeds
in the solution of aluminum did not affect the germination, root tap emission and the
growth of seedlings until 1280?M. With the increased of time of contact with the Al
solution, the young roots have been injured especially in papaya seedlings. The use of
stains pyrocatechol violet and hematoxylin were both efficient to determinate the
aluminum tolerance in papaya and passion fruit, but just pyrocatechol violet could
compare the doses used, produced a color gradient with increasing concentration of
aluminum. With the use of hematoxylin was only possible to separate the high
concentrations of low concentrations of aluminum. The best passion fruit cultivar was
IAC 273/277and papaya was Tainung / Os estudos da toler?ncia ao alum?nio em pl?ntulas de maracuj? (cvs. IAC-273/277, IACPaulista,
IAC-275, FB-100) e mam?o (cvs.Tainug, Golden, Gran Golden, Baixinho de
Santa Am?lia) foram realizados, em c?mara de crescimento nos Laborat?rios de
Qu?mica da Rizosfera e Laborat?rio de Analise de Sementes, Departamento de
Fitotecnia, Instituto de Agronomia da Universidade Federal Rural Rio de Janeiro.
Foram realizados experimentos com diferentes concentra??es de alum?nio em solu??o
nutritiva simples (com c?lcio) e completa, para analise do crescimento radicular
utilizando os par?metros comprimento radicular, taxa de crescimento radicular,
elonga??o radicular relativa, di?metro do colo, di?metro de ?pice da raiz principal bem
como testes com corantes. Foi tamb?m realizado estudos do efeito da embebi??o das
sementes com solu??es de alum?nio para verificar o efeito na porcentagem de
germina??o, pl?ntulas normais e anormais, e n?o germinadas. O uso da solu??o nutritiva
simples para realizar testes de curta dura??o de contacto ao alum?nio, n?o foi satisfat?rio
para mam?o, sendo mais adequado o uso de solu??o nutritiva completa. Em maracuj?,
ambas as solu??es podem ser utilizadas. As pl?ntulas de maracuj? crescidas em solu??o
simples com o aumento do tempo de contacto com alum?nio na solu??o, as ra?zes
ficaram endurecidas. Em concentra??es acima de 160?M de alum?nio, ocorreu efeito
fitotoxico, contudo em concentra??es menores que 80?M ocorreu at? aumento do
crescimento radicular para mam?o e maracuj?. O comprimento radicular foi o mais
eficiente par?metro indicador da toler?ncia ao alum?nio. A embebi??o das sementes em
alum?nio n?o afetou a germina??o a emiss?o da raiz principal e o crescimento da
pl?ntula at? a concentra??o da solu??o de embebi??o de 1280?M, mas a medida que
aumentou o tempo de contato e a concentra??o de alum?nio, as ra?zes rec?m emitidas
sofreram danos, principalmente as de pl?ntulas de mam?o. O uso dos corantes qu?micos
violeta de pirocatecol e hematoxilina foram eficiente na determina??o da toler?ncia ao
alum?nio em maracuj? e mam?o, mais somente o violeta de pirocatecol permitiu
comparar as doses entre si, gerando um gradiente de colora??o com o aumento da
concentra??o de alum?nio, com o uso da hematoxilina s? foi poss?vel separar as
concentra??es altas das concentra??es baixas de alum?nio. As melhores cultivares nas
condi??es testadas foi a IAC 273/277 de maracuj? e a cv Tainung de mam?o
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Nanocaractérisation d'oxydes à changement de résistance pour les mémoires résistivesCalka, Pauline 17 October 2012 (has links) (PDF)
En raison de leur faible consommation d'énergie, les mémoires non volatiles (MNV) sont En raison de leur faible consommation d'énergie, les mémoires non-volatiles sont particulièrement intéressantes pour l'électronique portative (clé USB, téléphone, ordinateur portable ...). Les mémoires Flash, qui dominent le marché, atteignent leurs limites physiques et doivent être remplacées. L'introduction de nouveaux matériaux et architectures mémoire est proposée. Les mémoires OxRRAM (Oxide Resistive Random Access Memory) sont des candidats potentiels. Il s'agit de structures M-O-M (Métal-Oxyde-Métal). Le stockage de l'information est basé sur la modulation de la résistance de l'oxyde à l'application d'un champ électrique ou d'un courant. Une meilleure compréhension du mécanisme de changement de résistance de ces dispositifs est nécessaire pour contrôler leurs performances. Nous nous intéressons au claquage diélectrique de l'oxyde, qui initie le mécanisme de changement de résistance. Les mesures physico-chimiques à l'échelle nanométrique sont indispensables à sa compréhension et font défaut dans la littérature. Dans cette thèse, nous proposons des mesures physico-chimiques, des mesures électriques et des méthodes de préparation d'échantillon adaptées. Les oxydes de nickel et d'hafnium sont investigués. En plus de la dégradation électrique (chute de résistance), les modifications de ces deux oxydes sont investiguées à trois niveaux : la composition chimique, la morphologie et la structure électronique. Mots-clés : mémoire résistive, mécanisme de changement de résistance, claquage diélectrique, NiO, HfO2, spectroscopie de photoélectrons, microscopie électronique en transmission, microscopie à forme atomique, lacunes d'oxygène.
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Sinchroninis ir asinchroninis užklausų srautų apdorojimas JAVA programavimo kalbos priemonėmis / Synchronous and asynchronous request stream handling in javaBlaževič, Pavel 02 July 2014 (has links)
Šio magistrinio darbo tikslas yra teoriškai ir praktiškai išnagrinėti kaip ir kokius žinomus užklausų srautų aptarnavimo sprendimo būdus galima realizuoti JAVA programavimo kalbos priemonėmis. Darbo metu iškeltus uždavinius sudaro konkurentiškumą valdančių modelių išnagrinėjimas, jų realizavimo JAVA programavimo kalbos priemonėmis analizė, realiai veikiančių komponentų sumodeliavimas ir sukūrimas, sukurtų konkurentiškumą valdančių komponentų tyrimas, išvadų bei rekomendacijų pateikimas siekiant perteikti darbo metu įgytas žinias kaip galima parametrizuoti užklausų srautų aptarnavimo komponentą užtikrinant optimalų išteklių panaudojimo, pralaidumo bei uždelsimo balansą. Darbo metu buvo nagrinėjami dviejų tipų konkurentiškumą valdantys modeliai, t.y. gijos pagrindu bei du įvykių išskyrimo ir reagavimo pagrindu realizuoti modeliai, kur pastarieji du buvo suprojektuoti atsižvelgiant į Douglas Schmidto siūlomas reaktoriaus ir proaktoriaus projektavimo schemas. Išanalizavus JAVA programavimo kalbos galimybes, paaiškėjo, kad visus modelius galima kuo puikiausiai sumodeliuoti ir realizuoti panaudojant sinchroninį besiblokuojantį įvedimo ir išvedimo posistemį, sinchroninį nesiblokuojantį įvedimo ir išvedimo posistemį (NIO) ir asinchroninį įvedimo ir išvedimo posistemį (AIO4J). Minėtas aukščiau konkurentiškumą valdantis komponentas buvo realiai panaudotas ir išbandytas sukurtame supaprastintame HTTP serveryje, kaip komponentas atsakingas už ryšio užmezgimą bei užklausų apdorojimą... [toliau žr. visą tekstą] / The purpose of this master thesis is to analyze how many of known solutions for request stream handling can be implemented in JAVA programming language. Also, in addition to it, this master thesis analyzes the way those solutions can be implemented using JAVA programming language. There are defined tasks to investigate in the scope of this thesis, which include following: exploration of well known concurrency managing models; analysis of their implementation possibilities in JAVA by designing and creating real working components; their implementation workflow research under various stress loaded conditions and, finally, supply recommendations for optimal parameterization for mentioned component to gain the best possible balance of resource utilization, throughput and latency. There were analyzed basically two types of concurrency managing models in this work, i.e. thread based and two models based on event notification principle, designed using Douglas Schmidt reactor and proactor design patterns. During exploration of JAVA programming language possibilities to implement above mentioned models a special attention was paid to the new input/output system (NIO) which provides synchronous non-blocking input/output operations, whereas to process operations asynchronously there was explored asynchronous execution of input/output operations by using JAVA non-native external AIO4J library created by IBM corporation. In order to perform stress and performance benchmarks for created... [to full text]
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Nanostructured Transition Metal Oxides in Cleantech Application : Gas Sensors, Photocatalysis, Self-cleaning Surfaces Based on TiO2, WO3 and NiOTopalian, Zareh January 2011 (has links)
This thesis focuses on the application of nanocrystalline transition metal oxide TiO2, WO3 and NiO thin films in new “green” building technologies. Specifically, their physicochemical properties in photocatalytic, self-cleaning and gas sensing applications are studied. There is an intimate connection between comfort issues, health, with connections to energy efficiency, leading to a need for intelligent building materials and green architecture. The importance of good indoor environment is augmented by the fact that modern man in developed countries spends some 90 % of his time inside buildings and vehicles. Poor air quality may lead to discomfort of the person inhabiting a building and in ultimately cause adverse health effects. Thin films of nanocrystalline TiO2 were prepared using reactive DC magnetron sputtering. Crystalline mesoporous films of WO3 and NiO were prepared using advanced gas deposition technique (AGD). The crystal structure, morphology, optical and chemical properties of the films were characterized by using grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy (SEM), UV/Vis spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively. The photocatalytic properties and adsorption of both organic and inorganic molecules on pure and functionalized films were probed by in situ Fourier transform infrared spectroscopy (FTIR). The gas sensing properties of sensors based on TiO2, WO3 and NiO were investigated by conductivity measurements and noise spectroscopy. It was found for the first time that NiO based thin film sensors can be used to detect H2S and NO2 at low temperatures – down to room temperature. Hybrid WO3 sensors functionalized with multiwalled carbon nanotubes (MWCNTs) were used to detect NO2, CO and NH3 gases. These hybrid gas sensors show improved recovery properties compared to unmodified WO3 sensors. TiO2 based gas sensors were able to detect low concentrations of H2S by noise spectroscopy provided that the sensors were irradiated by UV light. Furthermore we show that sulphur is photo-fixated in crystalline TiO2 films upon simultaneous SO2 gas exposure and UV irradiation. Studies of the kinetics and identity of the photo-fixated sulphur complexes show that these are formed by photo-induced reactions between oxygen and SO2 at oxygen surface vacancy sites in TiO2. The sulphur modified TiO2 films show interesting self-cleaning properties compared to the pure films. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 739
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Apatite based materials for solid oxide fuel cell (SOFC) and catalytic applicationsGasparyan, Hripsime 01 October 2012 (has links)
Low cost silicates with apatite-structure (general formula of apatite A10-xM6O26±δ, where A = rare earth or alkaline earth and M= Si, Ge, P, V..) have been proposed recently as promising solid electrolyte materials (oxygen ion conductors) for use at intermediate temperature solid oxide fuel cells (SOFCs). These materials exhibit sufficiently high ionic conductivity (e.g. ~ 0.01 S cm-1 at 700 oC), which is dominated by the interstitial site mechanism and can exceed that of yttria-stabilized-zirconia (YSZ), the solid electrolyte used in state-of-the-art SOFCs. The apatite structure is tolerant to extensive aliovalent doping, which has been applied for improving ionic conductivity. In this work are presented results concerning synthesis, conductivity and catalytic characterization of Fe- and/or Al-doped apatite type lanthanum silicates (ATLS) of the general formula La10-zSi6-x-yAlxFeyO26±δ as well as electrochemical characterization of interfaces of ATLS pellets with perovskite and Ni-based electrodes. The aim was to investigate the properties of these ATLS material, in particular as it concerns their potential use as SOFC components or as catalysts in oxidation reactions.
The conductivity of pellets prepared from ATLS powders synthesized via four different methods and having different grain size was measured under air and at different temperatures in the range 600 -850 oC, aiming to identification of the effect of composition (doping), method of synthesis, grain size and pellet sintering conditions. For electrolytes of the same composition, those prepared via mechanochemical activation exhibited the highest conductivity, which was improved with increasing Al- and decreasing Fe-content.
In state-of-the-art SOFCs perovskite electrodes are used as cathodes and Ni-based electrodes as anodes, thus electrochemical characterization of perovskite and Ni-based/ATLS interfaces was carried out. As it concerns perovskite/ATLS interfaces, the characterization focused on the study of the open circuit AC impedance characteristics of a La0.8Sr0.2Ni0.4Fe0.6O3-δ/La9.83Si5Al0.75Fe0.25O26±δ interface, at temperatures 600 to 800 oC and oxygen partial pressures ranging from 0.1 to 20 kPa. Under the aforementioned conditions, it was observed that the impedance characteristics of the interface were determined by at least two different processes, corresponding to two partially overlapping depressed arcs in the Nyquist plots. The polarization conductance of the interface was found to increase with increasing temperature as well as with increasing oxygen partial pressure, following a power law dependence. The electrochemical characterization of Ni-based electrodes/ATLS interfaces involved study of the electrochemical characteristics of NiO-apatite cermet electrodes as well as a Ni sputtered electrode interfaced with Al- or Fe-doped apatite electrolytes, under hydrogen atmospheres. The impedance characteristics of these electrodes were found to be determined by up to three different processes, their relative contribution depending on the electrode microstructure, Ni content (as it concerns the cermet electrodes), temperature, hydrogen partial pressure and applied overpotential.
Aiming to investigation of potential catalytic properties of ATLS materials the catalytic activity for CO combustion of a series of ATLS powders was studied. For this purpose, two series of apatite-type lanthanum silicates La10-xSi6-y-zAlyFezO27-3x/2-(y+z)/2 (ATLS), undoped or doped with Al and/or Fe, were synthesized via sol-gel and modified dry sol-gel methods and tested as catalysts for CO combustion. The experiments revealed that the ATLS powders were catalytically active for CO combustion above approximately 300 oC, with light-off temperatures T50 (50% conversion of CO) ranging from 505 to 629 oC. The study focused on the effect on catalytic activity of the synthesis method and doping with Al and/or Fe. Non-doped ATLS with stoichiometric structure, namely La10Si6O27 prepared via the sol-gel method, exhibited the highest catalytic activity for CO oxidation among all tested compositions, the comparison being based on the measured catalytic rate (expressed per surface area of the catalyst) under practically differential conditions. Compared to La-Sr-Mn-O and La-Sr-Co-Fe-O perovskite powders, the tested ATLS powders exhibited lower catalytic activity for CO oxidation. / -
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Atratividade cultural e potencialidade tur?stica: an?lise do evento Auto de Natal (Natal RN)Cunha, Shirley de Lima 13 September 2013 (has links)
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Previous issue date: 2013-09-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Inserted in the schedule for Christmas celebration in the city of Natal,
capital of the state of Rio Grande do Norte, Brazil, the spectacle so called Auto de
Natal mixes the Christmas story of Jesus birth with cultural and natural heritage of
the state, making possible the integration of professionals from various fields, such
as: literature, theater, dance and music. Important for local identity, Auto de Natal
integrates elements of intangible heritage in the state. In this context, the research
analyzed the perceptions of those who were involved in the production, presentation
and organization of the event, planned to be culturally attractive to tourism. For this, it
was used the descriptive and exploratory method, making use of documental,
bibliographic and field researches. It was applied qualitative techniques to the
interpretation of the interviews, while it was applied quantitative techniques to
analyze the questionnaires. The research has discovered that Auto de Natal has the
potential to add value to Cultural Tourism, diversifying the tourism product. The
research has also observed that most of the respondents recognized Auto de Natal
as intangible heritage, and concluded that the Christmas theme, which is alluding to
the nomenclature of destiny, needs to be well-done to attract more tourists to
experience the Natal in Natal / Inserido na programa??o natalina da capital do Rio Grande do Norte,
Natal, o espet?culo Auto de Natal mescla a hist?ria do nascimento de Jesus Cristo a
aspectos do patrim?nio cultural e natural do Estado, possibilitando a integra??o de
profissionais de diversas ?reas, dentre elas, literatura, teatro, dan?a e m?sica.
Importante para a identidade local, o Auto de Natal integra elementos do patrim?nio
imaterial potiguar. Nesse contexto, a pesquisa analisou a percep??o dos agentes
envolvidos na produ??o, encena??o e gest?o do evento, concebido enquanto
atrativo cultural e tur?stico. Para isso, utilizou-se do m?todo descritivo-explorat?rio,
realizando pesquisa de campo, bibliogr?fica e documental. T?cnicas qualitativas
foram aplicadas para a interpreta??o das entrevistas realizadas, enquanto t?cnicas
quantitativas foram utilizadas para a an?lise dos question?rios. A pesquisa constatou
que o Auto de Natal tem potencial tur?stico para agregar valor ao Turismo Cultural,
diversificando a oferta de produtos tur?sticos. Observou-se que a maioria dos
respondentes reconhece o Auto de Natal como patrim?nio imaterial. Concluiu-se que
a tem?tica natalina alusiva ? nomenclatura do destino, se bem trabalhada, atrair?
mais turistas para vivenciar o Natal em Natal
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S?ntese de p?s comp?sitos nanoestruturados (WC-Ni) por carborredu??o do APT com Ni (NO3)2.6H2O e sua sinteriza??o em forno a v?cuo e via SPS / Synthesis of nanostructured composite powders (WC-Ni) via APT carborreduction with Ni (NO3) 2.6H2O and hard metal applicationLima, Maria Jos? Santos 18 July 2017 (has links)
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Previous issue date: 2017-07-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho foram sintetizados p?s-comp?sitos WC-Ni atrav?s de Carborredu??o da mistura de paratungstato de am?nio hidratado (APT) com o nitrato de n?quel nas propor??es (5% p.Ni, 10% p.Ni e 15% p.Ni) a baixa temperatura (800?C a 950?C) e em curto tempo de rea??o (90 min a 150 min) em um ?nico processo de s?ntese. Os p?s foram caracterizados por difra??o de raios X, microscopia eletr?nica de varredura, espectroscopia de energia dispersiva (EDS), e fluoresc?ncia de raios X (FRX), an?lise de tamanho de part?culas e adsor??o de nitrog?nio pela t?cnica do BET, al?m de medidas de magnetiza??o, coercividade e reman?ncia. O estudo do tamanho de cristalito foi obtido a partir dos dados dos difratogramas de raios X dos p?s-comp?sitos, atrav?s da equa??o de Scherrer. Foi realizado um planejamento experimental fatorial 23 com tr?s pontos centrais com a finalidade avaliar a influ?ncia das condi??es de s?ntese nas vari?veis-resposta. Os par?metros de s?ntese avaliados neste trabalho foram: tempo de rea??o (90min, 120min e 150min), temperatura de s?ntese (800?C, 850?C e 900?C) e concentra??o de n?quel em peso (5%p.Ni, 10%p.Ni e 15%p.Ni). Foi poss?vel produzir p?s-comp?sitos de WC-Ni nonom?tricos nas propor??es desejadas com a pureza desejada, com tamanho m?dio de cristalito variando de 24,2 nm at? 38 nm, com ?rea superficial variando de 24,6 m?/g at? 46,7 m?/g. Os p?s apresentaram morfologia com part?culas de tamanhos e formas variadas, bastante aglomeradas, bem como uma boa dispers?o e homogeneiza??o das fases. As caracter?sticas espec?ficas desses materiais nanom?tricos proporcionam a sua utiliza??o tanto para a produ??o de metal duro como em rea??es catal?ticas. Os p?s-comp?sitos obtidos neste trabalho foram aplicados na produ??o de metal duro-WC-Ni atrav?s de sinteriza??o em fase s?lida e l?quida, utilizando as t?cnicas de sinteriza??o convencional e sinteriza??o por ?spark plasma sintering? para fins de compara??o. Nas amostras sinterizadas, foram realizadas medidas de dureza Vickers e densidade por picnometria. Tamb?m foram realizadas an?lises de DRX, MEV e EDS com mapeamento. Os melhores resultados para as os sinterizados de WC-Ni, foram obtidos para as amostras sinterizadas via SPS a 1350?C, apresentando dureza Vickers (2322 HV) e densidade (97,67 %) superiores as das amostras sinterizadas por sinteriza??o convencional a maiores temperaturas. / In this work WC-Ni composite powders were synthesized by carborreduction of the hydrated ammonium paratungstate (APT) mixture with the nickel nitrate in proportions (5% p.Ni, 10% p.Ni and 15% p.Ni) a low temperature (800 ? C to 950 ? C) and small reaction time (90min to 150min) in a single synthesis process. The powders were characterized mainly by X-ray diffraction, scanning electron microscopy (SEM), dispersive energy spectroscopy (EDS), X-ray fluorescence (FRX), particle size analysis and (BET) and measures of magnetization, coercivity and remanence. The study of crystallite size was obtained from the X-ray diffractograms of post-composites, using the Scherrer equation. A factorial experimental design 23 with three central points was carried out to evaluate the influence of the synthesis conditions on the response variables (crystallite size). The synthesis parameters evaluated in this work were: reaction time (90min, 120min and 150min), synthesis temperature (800 ? C, 850 ? C and 900 ? C) and concentration of nickel by weight (5% p.Ni, 10 % P.Ni and 15% p.Ni). It was possible to produce nanometric WC-Ni composite powders in the desired proportions with the desired purity, with a mean crystallite size varying from 24.2 nm to 38 nm, with a surface area ranging from 24.6m?/g to 46.7 m?/g. The powders presented morphology with particles of varied sizes and shapes, quite agglomerated and also presented a good dispersion and homogenization of the phases. The specific characteristics of these nanometric materials provide their use for both the hard metal in catalytic reactions.Therefore, the composite powders obtained in this work were applied in the production of WC-Ni hard metal by solid and liquid phase sintering using conventional sintering and Spark Plasma Sintering techniques for comparison purposes. In the sintered samples the measurements of Vickers hardness and density by pycnometry were performed. We also performed XRD, SEM and EDS analyzes with mapping. The best results for the sintered WC-Ni were obtained for the sintered samples via SPS at 1350?C, showing Vickers hardness (2322 HV) and density (97.67%) higher than the samples sintered by conventional sintering at higher temperatures. / 2018-08-23
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Avalia??o de catalisadores a base de carv?o da pir?lise do lodo de esgoto e carbetos de molibd?nio na transesterifica??o met?lica do ?leo de soja / Catalytic evaluation of coal derived from sewage sludge pyrolysis and molybdenum carbides materials from methyl transesterification reaction of soybeanAlexandrino, Angelinne Costa 29 September 2017 (has links)
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Previous issue date: 2017-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / H? d?cadas que a produ??o de combust?veis alternativos visando ? substitui??o do petr?leo e de seus derivados tem despertado o interesse de muitos pesquisadores em todo o planeta. Biodiesel ? uma alternativa renov?vel, o qual pode ser produzido a partir de ?leos residuais, gorduras animais e ?leos vegetais atrav?s do processo de transesterifica??o heterog?nea utilizando ?lcoois. Nesse contexto, catalisadores heterog?neos t?m se apresentado como potencial na produ??o de biodiesel em raz?o da possibilidade do seu reuso e por ser um processo mais limpo e eficiente. No presente trabalho, carv?o ativado obtido da pir?lise do lodo de esgoto (C.A), Mo2C, Mo2C/C.A e Ni (20%)-Mo2C/C.A foram avaliados no processo de transesterifica??o met?lica do ?leo de soja refinado visando ? produ??o de biodiesel. O carv?o do lodo foi tratado com o KOH no sentido de abrir os poros e promover maior ?rea especifica de contato, seguido de ativa??o f?sica. Os catalisadores a base de molibd?nio foram sintetizados a partir da rea??o g?s-s?lido utilizando como precursor heptamolibdato de am?nio e uma mistura de CH4/H2. Todos os materiais foram caracterizados utilizando as an?lises de TG, DRX, FRX, MEV, B.E.T e granulometria a laser. O processo de transesterifica??o foi avaliado em um reator de mistura constitu?do de um sistema de aquecimento e refluxo da fase alco?lica. Em temperatura constante de 65 oC, as condi??es operacionais estudadas para a rea??o foram: a natureza e concentra??o m?ssica (1 a 5%) do catalisador em rela??o ? massa do ?leo, a raz?o molar ?leo/?lcool (1/6 a 1/18), o pH do meio reacional (2,0 a 8,5), o tempo de rea??o (3 e 5 h) e a velocidade de agita??o da fase l?quida (450 e 600 rpm). Para todas as condi??es e demais catalisadores, o biodiesel foi produzido. A convers?o m?xima do ?leo de soja encontrada foi de 27,34%, no estudo cin?tico, para o catalisador Mo2C/C.A nas condi??es operacionais de 1% de catalisador, 6 h de rea??o, raz?o molar ?leo/?lcool de 1/12 e pH = 5. Na an?lise de caracteriza??o de uma amostra de biodiesel produzido o ponto de fulgor apresentou valor de 141 ?C, o qual est? acima do m?nimo especificado pela ANP. Um modelo cin?tico pseudo homog?neo foi utilizado, para o catalisador Mo2C/C.A atrav?s do qual foi mostrado que os resultados experimentais se ajustaram satisfatoriamente a uma cin?tica de 1? ordem, cuja constante cin?tica de velocidade teve como valor 0,0009 min-1. / For decades, the production of environment-friendly fuels, as alternative power sources for oil, has gained attention and interest of researchers worldwide. Biodiesel is a renewable alternative fuel that can be obtained from residual oils, animal fat and vegetable oils through heterogeneous transesterification reaction using alcohol. In this context, heterogeneous catalyst present potential for biodiesel production as they can be regenerated and provide a cleaner and more efficient process. In this work, several molybdenum carbide catalysts were tested for the transesterification reaction of soybean oil with methanol towards producing biodiesel. These catalysts were pure Mo2C, Mo2C supported over activated carbon (A.C), pure A.C and bimetallic Ni (20%)-Mo2C/A.C being this support produced from sewage sludge pyrolysis. The pyrolysis product was treated with KOH, in order to increase its porosity and promote a larger specific surface area, and later physically activated. Gas solid reaction with CH4 and H2 atmosphere was used to produce the studied molybdenum derived catalysts, and ammonium molybdate was used as molybdenum source in all cases. All catalysts were characterized in a TG, XDR, XFR, SEM, B.E.T and laser particle size analysis basis. Their activity towards transesterification reaction was evaluated by using a mixing reactor with temperature control and alcohol reflux at 65 ?C. The parameters that were manipulated for this experimental evaluation were: type and mass concentration of the catalyst (1 to 5%), oil/alcohol ratio (1/6 to 1/18), pH (2.0 to 8.5), reaction time (3 and 5h) and liquid phase agitation speed (450 and 600 rpm). For all conditions and other catalysts, biodiesel was produced. The maximum conversion found was 27.34% for the Mo2C/A.C catalyst under the operating conditions of 1% catalyst, 6 h reaction, oil/alcohol ration of 1/12 and pH = 5. In the characterization analysis of a sample of biodiesel produced the flash point presented a value of 141 ?C, which is above the minimum specified by the ANP. A pseudo homogeneous kinetics model was used, and experimental data presented agreement with a 1st order reaction with speed rate constant of 0,0009 min-1.
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