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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.
191

Compara??o do potencial herbicida do glifosato e seus complexos met?licos atrav?s de estudo enzim?tico e de metab?litos em Glycine max e Brachiaria decumbens / Comparison of herbicide potential of glyphosate and its metal complexes by enzymatic and metabolites studies in Glycine max and Brachiaria decumbens

SILVA, Soraia John da 20 August 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-02T19:54:07Z No. of bitstreams: 1 2015 - Soraia John da Silva.pdf: 1762972 bytes, checksum: aae3e43996736241367a1924339662c0 (MD5) / Made available in DSpace on 2017-06-02T19:54:07Z (GMT). No. of bitstreams: 1 2015 - Soraia John da Silva.pdf: 1762972 bytes, checksum: aae3e43996736241367a1924339662c0 (MD5) Previous issue date: 2015-08-20 / CAPES / The glyphosate, herbicide used in different countries, inhibits the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), blocking the synthesis of aromatic amino acids. With this, it still affects the activity of phenylalanine ammonia lyase (PAL) and the concentration of metabolites in plants. Its activity was first reported as a metal chelator. Therefore, to make use of this herbicide, may be formation of complexes with metals from soil, occurring change in the effectiveness of the product and loss of minerals. Thus, to avoid such problems,this study aimed to compare the effectiveness of three forms of glyphosate: purified, previously complexed with metals, and a commercial form (Roundup WG?). The effects of glyphosate complexes with copper, cobalt and nickel with different stoichiometries and different pH values on the in vitro activity of EPSPs were evaluated. Selected complex for the first experiment in vivo were Cu421 and Co821 (first number for pH and the latter two to stoichiometry glyphosate: metal). These complexes were used in the in vivo experiment I, as well as distilled water (control), purified Roundup and glyphosate on transgenic soybean and B. decumbens. In the following experiments (II and III), mineral oil was used in all treatments to reduce leaching of the compounds. The complex selected for continuation of this study was Cu421 due to its emphasis on the results obtained in the first experiment in vivo. When comparing the effect of the compounds in Falker Chlorophyll Index (ICF) of B. decumbens compared to control, there was fall of this index when using Roundup, Cu421 and purified glyphosate (the latter only in the second experiment). Later it was analyzed fresh mass accumulation and collected fresh material for determination of enzyme activities and N-NO3- levels. The complex Cu421 caused a more significant fresh mass reduction and still allowed the increase in the content of soluble nitrate in Brachiaria decumbens, probably due to the presence of nitrate in this complex. In the case of transgenic soybean there was no significant change in ICF. The use of Roundup and the complex did not change significantly the fresh mass accumul ation in this species. The application of the purified glyphosate, however, caused increase in mass accumulation and all treatments altered soybeans in nitrate content. In experiments with mineral oil in B. decumbens, the Cu421 complex inhibited significantly the EPSPs activity, as well as purified Roundup and glyphosate (the latter only in the experiment III). No inhibition occurred in transgenic soybean. All treatments in vivo stimulated PAL activity only on weed, which suggests that the increase in this activity is a consequence of the inhibition of EPSPs and other deleterious effects of compounds on susceptible plants. This study showed that especially Cu421 complex might be used effectively as a herbicide since it inhibits EPSPs, activates the PA,L reduces fresh mass accumulation and influences photosynthesis in the tested weed. Besides, the transgenic soybean showed little sensitive to this compound, which further increases the prospect of using the same as herbicide. / O glifosato, herbicida usado mundialmente, atua inibindo a enzima 5-enolpiruvil-chiquimato- 3-fosfato-sintase (EPSPs), bloqueando a s?ntese de amino?cidos arom?ticos. Com isso, ainda influencia a atividade de fenilalanina am?nia liase (PAL) e a concentra??o de metab?litos nas plantas. A sua primeira a??o reportada foi como agente quelante de metais. Portanto, ao fazer uso deste herbicida, pode haver forma??o de complexos com metais do solo, ocorrendo altera??o da efic?cia do produto e defici?ncia mineral. Assim, de modo a evitar tais problemas, este trabalho teve como objetivo, comparar a efici?ncia de tr?s formas de glifosato: purificado, previamente complexado com metais, e uma das suas formas comerciais (Roundup WG?). Os efeitos de complexos de glifosato com cobre, cobalto e n?quel, sintetizados sob diferentes estequiometrias e valores de pH, foram avaliados sobre a atividade in vitro de EPSPs. Os complexos selecionados para o primeiro experimento in vivo foram: Cu421 e Co821 (primeiro n?mero referente ao pH e os dois ?ltimos ? estequiometria glifosato:metal). Estes complexos foram usados no experimento in vivo I, assim como ?gua destilada (controle), Roundup e glifosato purificado, sobre soja transg?nica e Brachiaria decumbens. Nos experimentos seguintes utilizou-se ?leo mineral em todos os tratamentos para reduzir a lixivia??o dos compostos. O complexo selecionado para continua??o deste estudo foi o Cu421 devido a seu destaque nos resultados obtidos no primeiro experimento in vivo. Ao comparar o efeito dos compostos no ?ndice de Clorofila Falker (ICF) de B. decumbens em rela??o ao controle, observou-se queda deste ?ndice ao usar Roundup, Cu421 e glifosato purificado (este ?ltimo, somente no segundo experimento). Posteriormente foi analisado ac?mulo de massa fresca e coletado material fresco para determina??o das atividades enzim?ticas e dos teores N-NO3-. O complexo Cu421 foi o que provocou maior redu??o da massa fresca e ainda possibilitou o aumento no teor sol?vel de nitrato em B. decumbens, provavelmente devido ? presen?a de nitrato neste complexo. No caso da soja transg?nica n?o houve altera??o significativa de ICF. O uso de Roundup e dos complexos n?o alterou de forma significativa o ac?mulo de massa fresca nesta esp?cie. A aplica??o do glifosato purificado, entretanto, causou incremento no ac?mulo de massa e todos os tratamentos alteraram o teor de nitrato em soja. Nos experimentos com ?leo mineral em B. decumbens, o complexo Cu421 inibiu de forma significativa a atividade de EPSPs, assim como Roundup e glifosato purificado (este ?ltimo, somente no experimento III). Em soja transg?nica n?o houve inibi??o. Todos os tratamentos in vivo estimularam a atividade de PAL somente na gram?nea, permitindo sugerir que o aumento nesta atividade seja consequ?ncia da inibi??o de EPSPs e de outros efeitos delet?rios dos compostos sobre plantas suscept?veis. O presente estudo mostrou que principalmente o complexo Cu421 pode vir a ser utilizado de forma eficaz como herbicida, uma vez que inibe a EPSPs, ativa a PAL, reduz ac?mulo de massa fresca e influencia a fotoss?ntese na planta daninha testada. E, em contrapartida, a soja transg?nica mostrou-se pouco sens?vel a este composto, o que aumenta ainda mais a perspectiva do uso do mesmo como herbicida.
192

Implementa??o de unidade experimental para controle da press?o anular de fundo durante o processo de cimenta??o de po?os de petr?leo / Implementation of experimental unit for downhole pressure control during the process of cementing well petroleum

COSTA, Frederico Martins 27 December 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-07-28T17:55:36Z No. of bitstreams: 1 2016 - Frederico Martins Costa.pdf: 7875693 bytes, checksum: 1f9e0aaff0875ac10e2311a35da16d31 (MD5) / Made available in DSpace on 2017-07-28T17:55:36Z (GMT). No. of bitstreams: 1 2016 - Frederico Martins Costa.pdf: 7875693 bytes, checksum: 1f9e0aaff0875ac10e2311a35da16d31 (MD5) Previous issue date: 2016-12-27 / CAPES / The process of well cementing is very complex, beyond the fact that cement paste presents high density, different rheology fluids are injected into the annulus, altering downhole pressure due to changes on hydrostatic pressure and frictional losses. Knowing the operational window and assuring downhole pressure inside this constraint is primordial for security and well life cycle purposes. Due to downhole variations caused by the disturbances, the superior (fracture) and inferior window limits can be exceeded. As a result, loss circulation problems (mud penetration into a fracture) or kick (reservoir fluid inflow into the annulus) can disturb the cementing process, leading to serious accidents, financial losses, environmental damage and human losses. In order to represent the most important phenomena of cementing process, an experimental unit was built using on line flow, density and pressure measurements. Downhole pressure control through pumping 8, 11 and 14 ppg (lb/gal) fluids was analyzed under loss circulation and kick phenomena. The tracking of the downhole pressure at the set point, by employing a feedback control loop (PI), was implemented through using the opening index of the choke valve as the manipulated variable. / O processo de cimenta??o de po?os ? bastante complexo, al?m da pasta de cimento apresentar elevada densidade e ocorrer o bombeio de fluidos de diferentes reologias, a press?o no fundo do po?o sofre grandes varia??es, devido ? mudan?a na press?o hidrost?tica do po?o e ?s perdas por atrito. Conhecer a janela operacional do po?o e manter a press?o anular de fundo dentro desta ? primordial para a seguran?a e a vida ?til do po?o. Devido ?s varia??es na press?o ocasionadas pelos dist?rbios, a press?o anular de fundo pode extrapolar o limite superior (press?o de fratura) e o inferior (press?o de poros), da janela operacional. Ao extrapolar tais limites, os fluidos da regi?o anular podem migrar para a fratura (perda de circula??o) ou os fluidos nativos do reservat?rio podem migrar para a regi?o anular (kick), essas situa??es s?o indesejadas durante a cimenta??o, podendo causar s?rios acidentes, perdas humanas, preju?zos financeiros e danos ambientais irrevers?veis. Para representar os fen?menos mais importantes do processo de cimenta??o, foi constru?da uma unidade experimental com instrumenta??o capaz de quantificar vaz?o, densidade e press?o em tempo real. Foram analisados o comportamento da press?o anular de fundo no bombeio de fluidos com diferentes densidades (8, 11 e 14 ppg), al?m dos fen?menos de perda de circula??o com kick de g?s, controlando a press?o em um valor desejado (set point), utilizando uma estrat?gia de controle por realimenta??o (controlador PI), atrav?s do ?ndice da abertura da v?lvula choke.
193

An?lise t?cnica e econ?mica da produ??o de biodiesel utilizando ?leo de fritura residual em unidade piloto / Techno-economic study of biodiesel production from waste frying oil in a pilot plant

DANTAS, Renata Ara?jo 15 December 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-07-28T18:32:47Z No. of bitstreams: 1 2016 - Renata Ara?jo Dantass.pdf: 3354692 bytes, checksum: 1d9395453e1cd720f2bd08e346ef7ce7 (MD5) / Made available in DSpace on 2017-07-28T18:32:47Z (GMT). No. of bitstreams: 1 2016 - Renata Ara?jo Dantass.pdf: 3354692 bytes, checksum: 1d9395453e1cd720f2bd08e346ef7ce7 (MD5) Previous issue date: 2016-12-15 / The increasing economic and technological development over the world has caused a huge demand of energy. In Brazil, the transportation sector is the main responsible for energy consumption in the country, reaching 45.2% of the diesel use. In this scenario, renewable fuels become an attractive alternative due to the numerous benefits attributed to their use, such as degradability, absence of toxicity, reduction of pollutant emission and renewable origin. As in other countries, Brazil has authorized the use of a minimum quantity of biodiesel in diesel. Currently, according to federal law n? 11.097/2005, the minimum mixing percentage is equivalent to 7% and during 2016, it will increase to 8%. However, the major challenge to produce biodiesel in a large-scale is the high operating cost. According to the literature, the raw material costs are so high, and correspond to 70-85% of the total cost of production. The use of alternative and low cost sources of triglycerides for biodiesel production has been extensively studied. Waste oil, from domestic and commercial consumption, is a potential residue because of its high quantity available and low aggregated value. In this context, the production of biodiesel in a pilot unit present in the UFRRJ was studied using the homogeneous alkaline transesterification reaction. The operational condition used in the pilot plant was previously determined from an experimental planning, choosing the best one that gave the high conversion and acceptable values of viscosity. The simulations were performed in the SuperPro Designer?, and the prices of materials, utilities, consumables and costs with operators were determined based on the domestic and international market. A previous analysis of the production of 250 kg/batch of biodiesel was economically viable considering the unit cost of biodiesel of $ 0.62/kg. The sensitivity analysis showed that the plant becomes economically viable from a biodiesel price equal or greater than $ 0.754/kg, almost 34 cents above the initially estimated value. In order to turn the biodiesel production more profitable, simulations were done with different vegetable oils with different levels of costs. The results were unsatisfactory from the economic point of view, confirming the importance of the use of low cost raw materials. A scale up was made from the pilot unit and the technical and economic data showed that the project becomes more profitable starting from the production of 2.500 kg of residual oil, presenting IRR and return time of respectively 116.9 % and 1 year. The production of biodiesel in the pilot unit was carried out and the specifications were compared to ANP. The values of viscosity, specific mass, flash point, iodine content and corrosivity were in the limit range established by ANP. / O crescente desenvolvimento econ?mico e tecnol?gico associado ao aumento populacional tem provocado uma grande demanda de energia. No Brasil, atrav?s do Balan?o Energ?tico Nacional divulgado pelo Minist?rio de Minas e Energia, foi apontado que o setor de transporte foi o maior respons?vel pelo consumo de energia no pa?s, sendo a maior parte (45,2%) referente ao uso de ?leo diesel. Neste cen?rio, os combust?veis renov?veis tornam-se uma alternativa atraente devido aos in?meros benef?cios atribu?dos ao seu uso, como degradabilidade, aus?ncia de toxicidade, redu??o da emiss?o de poluentes e origem renov?vel. Assim como em outros pa?ses, o Brasil autorizou o uso de misturas m?nimas obrigat?rias de biodiesel ao diesel. Atualmente, de acordo com a lei federal n?. 11.097/2005, o percentual de mistura m?nima ? equivalente a 7% e, para o ano de 2016, foi aprovado o aumento para 8%. Entretanto, a maior barreira para produ??o e utiliza??o de biodiesel em larga escala ? o elevado custo operacional. De acordo com a literatura, o custo de aquisi??o da mat?ria prima ? o mais alto e corresponde entre 70- 85% do custo total de produ??o. O uso de fontes de triglicer?deos alternativas e menos dispendiosas para produ??o de biodiesel tem sido amplamente estudada. O ?leo residual, proveniente do consumo dom?stico e comercial, ? uma fonte em potencial devido a sua vasta abund?ncia e baixo valor agregado. Neste contexto, a produ??o de biodiesel em uma unidade piloto presente na UFRRJ foi estudada a partir da rea??o de transesterifica??o homog?nea b?sica. A condi??o operacional empregada na planta piloto foi previamente determinada a partir de um planejamento experimental, objetivando maior convers?o e menor gasto energ?tico e material. Com aux?lio de um simulador comercial, SuperPro Designer?, o balan?o de massa e energia foi realizado. Com base no mercado nacional e internacional, os pre?os de materiais, utilidades, consum?veis e custos com operadores foram determinados. Uma an?lise pr?via da produ??o de 250 kg/batelada de biodiesel, de acordo com as opera??es unit?rias presentes na planta original, apresentou-se invi?vel economicamente considerando o custo unit?rio de biodiesel de $0,62/kg. A an?lise de sensibilidade mostrou que a planta torna-se vi?vel economicamente a partir de um pre?o de venda do biodiesel igual ou superior a $0,754/kg, 34 centavos acima do valor inicialmente estimado. Simula??es da produ??o de biodiesel na unidade piloto com ?leos vegetais de diferentes custos de aquisi??o foram realizadas. Os resultados mostraram-se insatisfat?rios do ponto de vista econ?mico, ratificando a import?ncia do uso de mat?rias-primas de baixo valor agregado. Um ?scale up? foi feito a partir da unidade piloto e os dados t?cnicos e econ?micos mostraram que o projeto torna-se mais lucrativo partindo da produ??o de 2.500 kg de ?leo residual, apresentando TIR e tempo de retorno de, respectivamente, 116,9% e 1 ano. A produ??o de biodiesel na unidade piloto foi realizada e o biodiesel produzido foi analisado e comparado quanto ?s especifica??es da ANP. Os valores de viscosidade cinem?tica, massa espec?fica, ponto de fulgor, ?ndice de iodo, corrosividade ao cobre e aspecto atenderam os limites preconizados pela ANP.
194

Caracteriza??o estrutural de Perovskitas Lax-1AxCoO3 (x=0 e 0,2) ,dopadas com c?lcio e bario, por espectroscopia de absor??o de raios X (XAS).

Gomes, Washington Charles de Macedo 09 September 2013 (has links)
Made available in DSpace on 2014-12-17T15:42:27Z (GMT). No. of bitstreams: 1 WashingtonCMG_TESE.pdf: 1906631 bytes, checksum: 6b7dc12db13ffeb89c11288d55cea5a8 (MD5) Previous issue date: 2013-09-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, the structures of LaCoO3, La0,8Ba0,2CoO3 and La0,8Ca0,2CoO3 perovskites were characterized as a function of temperature (LaCoO3 structure being analyzed only at room temperature). The characterization of these materials were made by X-Ray Absorption Spectroscopy (XAS), in the cobalt K-edge, taking into account the correlated Einstein model X-ray absorption fine structure (EXAFS). The first part of the absorption spectrum corresponded the X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). These materials were prepared by the combustion method. The combustion products were calcinated at 900 0C, for 6 hours in air. Noted that the sample LaCoO3 at room temperature and samples doped with Calcium and Barium in the temperature range of 50 K to 298 K showed greater distortion to monoclinic symmetry with space group I2/a. However, the sample doped with barium at the temperatures 50 K, 220 K, and 260 K showed a slight distortion to rhombohedral symmetry with space group R-3c. The La0,8Ca0, 2CoO3 structure was few sensitive to temperature variation, showing a higher local distortion in the octahedron and a higher local thermal disorder. These interpretations were in agreement with the information electronic structural on the XANES region and geometric in the EXAFS region / Neste trabalho foram investigados estruturas de perovskitas LaCoO3, La0,8Ba0,2CoO3 e La0,8Ca0,2CoO3 em fun??o de temperatura, sendo que a estrutura LaCoO3 foi analisada apenas em temperatura ambiente. As caracteriza??es destes materiais foram realizadas pela espectroscopia de absor??o de raios X (XAS) na borda K do cobalto levando em considera??o modelo de Einstein correlacionado na estrutura fina de absor??o (EXAFS). A primeira parte do espectro de absor??o de raios X corresponde absor??o de raios X pr?xima ? borda de absor??o (XANES) e a outra estende ? espectroscopia da estrutura fina de absor??o (EXAFS). Estes materiais foram preparados pelo m?todo de combust?o. Os produtos obtidos da combust?o foram tratados termicamente por 9000C por 6 horas nesses materiais. Observou que a amostra LaCoO3 em temperatura ambiente e as amostras dopadas com C?lcio e B?rio na faixa de temperatura entre 50 K a 298 K apresentaram uma maior distor??o com simetria monocl?nica com grupo espacial I2/a. No entanto, a amostra dopada com B?rio nas temperaturas 50 K, 220 K e 260 K mostrou uma leve distor??o com simetria rombo?drica com grupo espacial R-3c. A estrutura La0,8Ca0,2CoO3 foi pouco sens?vel com a varia??o de temperatura, apresentando uma maior distor??o local no octaedro e uma maior desordem t?rmica local. Estas interpreta??es est?o de acordo com as informa??es estruturais eletr?nica na regi?o XANES e geom?trica na regi?o EXAFS
195

Optimizaci��n del proceso de secado en base a criterios de calidad. Aplicaci��n al dise��o de un alimento c��rnico enriquecido en fibra alimentaria

Eim Iznardo, Valeria Soledad 10 September 2012 (has links)
En el dise��o de embutidos crudos curados enriquecidos en fibra alimentaria, es esencial la obtenci��n de ingredientes funcionales de elevada calidad, que puedan ser incorporados en la formulaci��n del embutido generando las menores modificaciones de las caracter��sticas f��sico-qu��micas y sensoriales del alimento. El principal objetivo de este trabajo consisti�� en optimizar la formulaci��n de un embutido crudo curado enriquecido en un concentrado de fibra alimentaria de zanahoria. La formulaci��n ��ptima debe proporcionar el contenido m��ximo de fibra alimentaria y producir los m��nimos cambios de calidad respecto al producto tradicional. Se ha propuesto una metodolog��a para optimizar ambos, la obtenci��n de un concentrado de fibra alimentaria de alta calidad y tambi��n la formulaci��n de un embutido crudo curado (sobrasada) enriquecido en fibra alimentaria. En primer lugar, se ha desarrollado un procedimiento que consiste en la modelizaci��n, simulaci��n y optimizaci��n del proceso de secado convectivo de zanahoria. El procedimiento de optimizaci��n no solo se refiere a la transferencia de materia, sino tambi��n se incluyen los criterios relacionados con los atributos de calidad del producto final. Una vez obtenido el ingrediente funcional de calidad, fue incorporado en la formulaci��n de la sobrasada. La cantidad ��ptima de concentrado de fibra alimentaria de zanahoria necesaria para obtener un embutido enriquecido de calidad se estim�� mediante el an��lisis de los efectos de la adici��n de fibra alimentaria de zanahoria en el proceso de maduraci��n-secado de sobrasada. / To design dry fermented sausages enriched in dietary fibre, it is essential to obtain high quality functional ingredients, which can be incorporated into sausage formulation with minor modifications of the physico-chemical and sensory properties of food. The main objective of this study was to optimize the formulation of a dry fermented sausage enriched with a dietary fibre concentrate from carrot. The optimal formulation should provide maximum dietary fibre content and produce minimal quality changes from the traditional product. A methodology has been proposed to optimize both the acquisition of a high quality fibre concentrate and also for the formulation of a dry fermented sausage (sobrassada) enriched in dietary fibre. First, a procedure comprised of mathematical modelling, simulation and optimization of the convective carrot drying process was developed. The optimization procedure was not only concerned with mass transfer but also included criteria related to quality attributes of the final product. Once the high quality functional ingredient was obtained, it was incorporated into the sobrassada formulation. The optimal amount of carrot dietary fibre concentrate necessary to obtain a high quality enriched sausage was estimated by analysing the effects of carrot dietary fibre addition to the ripening-drying process of sobrassada. / En el disseny d'embotits crus curats enriquits en fibra aliment��ria, ��s essencial l'obtenci�� d'ingredients funcionals d'elevada qualitat que puguin ser incorporats en la formulaci�� de l'embotit generant les menors modificacions de les caracter��stiques fisicoqu��miques i sensorials de l'aliment. El principal objectiu d'aquest treball va consistir a optimitzar la formulaci�� d'un embotit cru curat enriquit en un concentrat de fibra aliment��ria de pastanaga. La formulaci�� ��ptima ha de proporcionar el contingut m��xim de fibra aliment��ria i produir la menor quantitat possible de canvis qualitatius respecte al producte tradicional. S'ha proposat una metodologia per optimitzar ambd��s aspectes esmentats, l'obtenci�� d'un concentrat de fibra aliment��ria d'alta qualitat i tamb�� la formulaci�� d'un embotit cru curat (sobrassada) enriquit en fibra aliment��ria. En primer lloc, s'ha desenvolupat un procediment que consisteix en la modelitzaci��, simulaci�� i optimitzaci�� del proc��s d'assecatge convectiu de pastanaga. El procediment d'optimitzaci�� no nom��s fa refer��ncia a la transfer��ncia de mat��ria, sin�� que tamb�� inclou els criteris relacionats amb els atributs de qualitat del producte final. Una vegada obtingut l'ingredient funcional de qualitat, va ser incorporat en la formulaci�� de la sobrassada. La quantitat ��ptima de concentrat de fibra aliment��ria de pastanaga necess��ria per obtenir un embotit enriquit de qualitat es va estimar mitjan��ant l'an��lisi dels efectes de l'addici�� de fibra aliment��ria de pastanaga en el proc��s de maduraci��/assecat de sobrassada.
196

Modelos at?micos como objeto do saber no ensino de qu?mica: uma proposta metodol?gica baseada em elementos da engenharia did?tica

Da Silva, Cesar Alves 01 February 2018 (has links)
Submitted by Verena Pereira (verenagoncalves@uefs.br) on 2018-07-12T22:04:46Z No. of bitstreams: 1 CESAR ALVES_Disserta??o_Final revisado vera.pdf: 6440316 bytes, checksum: 9325061c1c7981117303732082343992 (MD5) / Made available in DSpace on 2018-07-12T22:04:46Z (GMT). No. of bitstreams: 1 CESAR ALVES_Disserta??o_Final revisado vera.pdf: 6440316 bytes, checksum: 9325061c1c7981117303732082343992 (MD5) Previous issue date: 2018-02-01 / The main objective of this work was to describe the concepts of Atomic Models, within the scenario of the teaching of chemical reactions, relating them empirically to the processes of chemical luminescence and contextualized to the phenomenon of the planetary Auroras. For this purpose, a proposal was presented to help chemistry teachers to provide students with a better understanding of more meaningful learning. The Teaching of Chemistry in Basic Education presents several challenges regarding the introduction of concepts related to the structure of matter. The approach of this project is centered in the interaction between the Astronomy and the Teaching of Chemistry, in an interdisciplinary perspective with focus in the course of didactic engineering. It is premised that this approach may attract the interest of high school students. The methodology was developed in the classrooms of the Luiz Eduardo Magalh?es College in Feira de Santana-BA. The use of a learning sequence, centered on experimental and observational phenomena where the student's performance is intensified by the possibility of self-regulation and confrontation with the proposed situations, enabled an evolution of strategies, enhancing students' cognition. In an enveloping and structured way in its four phases, the course of didactic engineering contributed to progress in improving teaching and learning, since the agreed proposal was executed and indicates that it is possible to favor the learning of concepts of Teaching Chemistry with emphasis to topics, motivating Students to learn / O principal objetivo deste trabalho foi descrever os conceitos de Modelos At?micos, dentro do cen?rio do ensino de rea??es qu?micas, relacionando-os empiricamente com os processos de luminesc?ncia qu?mica e contextualizados com o fen?meno das Auroras planet?rias. Para o efeito, foi apresentada uma proposta para ajudar os professores de qu?mica a oferecer aos alunos uma melhor compreens?o da aprendizagem mais significativa. O Ensino de Qu?mica na Educa??o B?sica apresenta v?rios desafios em rela??o ? introdu??o de conceitos relacionados ? estrutura da mat?ria. A abordagem deste projeto est? centrada na intera??o entre a Astronomia e o Ensino de Qu?mica, em uma perspectiva interdisciplinar com foco no curso da engenharia did?tica. Pretende-se que esta abordagem possa atrair o interesse dos alunos do ensino m?dio. A metodologia foi desenvolvida nas salas de aula do Col?gio Luiz Eduardo Magalh?es em Feira de Santana-BA. O uso de uma seq??ncia de aprendizagem, centrada em fen?menos experimentais e observacionais, onde o desempenho do aluno ? intensificado pela possibilidade de auto-regula??o e confronto com as situa??es propostas, permitiu uma evolu??o das estrat?gias, aprimorando a cogni??o dos estudantes. De forma envolvente e estruturada em suas quatro fases, o curso de engenharia did?tica contribuiu para o progresso na melhoria do ensino e da aprendizagem, uma vez que a proposta acordada foi executada e indica que ? poss?vel favorecer a aprendizagem de conceitos de Qu?mica de Ensino com ?nfase em t?picos, motivando esudantes para aprender
197

An?lise da viabilidade de aplica??o de res?duos da constru??o civil da Regi?o Metropolitana de Campinas em argamassas de uso geral por m?todo multicrit?rios / Analysis of the feasibility of applying construction waste from the Metropolitan Region of Campinas to mortars of general use by multi-criteria method

Petitto, R?gia Mara 21 June 2017 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-08-07T13:10:24Z No. of bitstreams: 1 R?GIA MARIA PETITTO.pdf: 3577833 bytes, checksum: 125f036f5ae5942ebbd9906d675670d3 (MD5) / Made available in DSpace on 2017-08-07T13:10:24Z (GMT). No. of bitstreams: 1 R?GIA MARIA PETITTO.pdf: 3577833 bytes, checksum: 125f036f5ae5942ebbd9906d675670d3 (MD5) Previous issue date: 2017-06-21 / The objective of this work was to characterize the recycled aggregates generated in the metropolitan region of Campinas and to test its application in the production of mortars for general use. From a qualitative approach, with an exploratory objective, the surveys of the current legislation and legal requirements imposed to solid waste management and the panorama of this management in the metropolitan region of Campinas were carried out. The six recycling plants for the disposal of construction waste (RCC) generated in the implanted municipalities were identified and, based on the data collected, a map with the geographic location of these plants was elaborated. After the sample collection, with a quantitative approach of applied nature and exploratory objective, analyzes of the physical characteristics were made (grain size composition, 75 ?m sieve material, water absorption, clay cladding content and friable materials, Specific mass and organic impurity) and chemical (soluble salts and organic matter content by fire loss) of these materials. All the analyzed aggregates presented satisfactory results in the granulometric composition and water absorption tests. Regarding the content of fine material (less than 75 ?m), clay content and friable materials and organic impurities, few samples could be accepted for use recommended by the Brazilian Association of Technical Standards (ABNT). The analysis of the soluble salts content would also make it impossible to accept the aggregate of some suppliers. With the replacement of natural aggregate by the recycled aggregates, mortars with a 1: 3 dash (cement: aggregate) were prepared, and 20 and 40% of the natural aggregate were replaced. The characteristics of the mortars in the fresh state (water retention, incorporated air content, mass density) and hardened (water absorption by capillarity, capillary coefficient, compressive strength, flexural tensile strength and apparent specific mass in the Hardened state). From the results obtained, the analytical Hierarchy Process (AHP) methodology showed the content of incorporation of the recycled aggregate in the production of general purpose mortars composed of cement and sand. For the application of this method, weights were assigned to punctuated criteria related to the physical and mechanical performance of mortars and environmental criteria related to the exhaustion of natural resources and transport distance. The best result was found in mortar with a 20% substitute content of mixed recycled aggregate by municipal unit from Campinas, but it is not possible to observe a tendency to obtain better results in mortars with lower substitution content, nor exclusively by mortars with mixed recycled aggregates. / O presente trabalho teve por objetivo caracterizar os agregados reciclados gerados na regi?o metropolitana de Campinas e testar sua aplica??o na produ??o de argamassas para uso geral. A partir de uma abordagem qualitativa, com objetivo explorat?rio, foram realizados os levantamentos da legisla??o vigente e exig?ncias legais impostas ? gest?o dos res?duos s?lidos e do panorama desta gest?o na regi?o metropolitana de Campinas. As seis usinas recicladoras para destina??o dos res?duos de constru??o civil (RCC) gerados nos munic?pios implantadas foram identificadas e, a partir dos dados coletados, elaborou-se um mapa com a localiza??o geogr?fica destas usinas. Ap?s a coleta de amostras, com abordagem quantitativa de natureza aplicada e objetivo explorat?rio, foram realizadas an?lises das caracter?sticas f?sicas (composi??o granulom?trica, teor de material passante na peneira de 75 ?m, absor??o de ?gua, teor de torr?es de argila e materiais fri?veis, massa espec?fica e impureza org?nica) e qu?micas (sais sol?veis e teor de mat?ria org?nica por perda ao fogo) destes materiais. Todos os agregados analisados apresentaram resultados satisfat?rios nos ensaios de composi??o granulom?trica e absor??o de ?gua. J? quanto ao teor de material fino (menor que 75 ?m), teor de torr?es de argila e materiais fri?veis e impurezas org?nicas, foram poucas as amostras que poderiam ser aceitas para o emprego recomendado pela Associa??o Brasileira de Normas T?cnicas (ABNT). A an?lise do teor de sais sol?veis tamb?m inviabilizaria a aceita??o do agregado de alguns fornecedores. Com a substitui??o de agregado natural pelos agregados reciclados foram preparadas argamassas com tra?o de 1:3 (cimento:agregado), e substitui??o de 20 e 40% do agregado natural. Foram determinadas as caracter?sticas das argamassas no estado fresco (reten??o de ?gua, teor de ar incorporado, densidade de massa) e endurecido (absor??o de ?gua por capilaridade, coeficiente de capilaridade, resist?ncia ? compress?o, resist?ncia ? tra??o na flex?o e massa especifica aparente no estado endurecido). A partir dos resultados obtidos verificou-se, por aplica??o do m?todo de avalia??o multicrit?rios, com a metodologia Analytic Hierarchy Process (AHP), o teor de incorpora??o do agregado reciclado na produ??o de argamassas de uso geral compostas por cimento e areia. Para a aplica??o deste m?todo foram atribu?dos pesos a crit?rios pontuados ligados ao desempenho f?sico e mec?nico das argamassas e crit?rios ambientais ligados ao esgotamento dos recursos naturais e dist?ncia de transporte. O melhor resultado foi encontrado na argamassa com teor de substitui??o de 20% de agregado reciclado misto da unidade municipal de Campinas, mas n?o ? poss?vel observar tend?ncia de obter melhores resultados em argamassas com menor teor de substitui??o, nem t?o pouco exclusivamente por argamassas com agregados reciclados mistos.
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A influ??ncia dos fatores contingenciais na intensidade de uso dos indicadores e direcionadores de valor das empresas do segmento qu??mico brasileiro

Alencar, Eduardo Pereira 21 August 2015 (has links)
Made available in DSpace on 2015-12-03T18:33:15Z (GMT). No. of bitstreams: 1 Eduardo_Pereira_Alencar.pdf: 864195 bytes, checksum: 49414a0dda4258b4ba2907032c458c67 (MD5) Previous issue date: 2015-08-21 / The contingency theory is premised a better fit between the internal contingency factors to the company and its external environment. From this perspective the research sought to understand the influence of contingencies factors: external environment to the company's operations and size, about the intensity in the use of the financial indicators and financial and non-financial value drivers on the brazilian chemical sector. Data were obtained by applying the questionnaire, multiple regression analysis was used to investigate the influence of the environment and size in intensity of use of value drivers. The results show that the uncertainty of the environmental factor influenced the intensity of use forming a basic set which mostly has financial drivers and financial indicators, but non-financial drivers were also validated in the regression to a lesser extent, the size influenced financial indicators and non-financial drivers the basic set of drivers and indicators formed can be seen as the best fit to environmental uncertainty and the size of the sample companies / A teoria da conting??ncia tem por premissa um melhor ajuste entre os fatores contingenciais internos ?? empresa e seu ambiente externo. Sob essa perspectiva a pesquisa procurou compreender a influ??ncia dos fatores contingenciais: ambiente externo ??s opera????es da empresa e porte, sobre a intensidade de uso dos indicadores financeiros e direcionadores de valor financeiro e n??o financeiro no segmento qu??mico brasileiro. Os dados foram obtidos pela aplica????o de question??rio, a an??lise de regress??o m??ltipla foi utilizada para verificar a influ??ncia do ambiente e porte na intensidade de uso dos direcionadores de valor. Os resultados apontam que a incerteza do fator ambiental influenciou a intensidade de uso formando um conjunto b??sico que em sua maioria possui direcionadores e indicadores financeiros, por??m direcionadores n??o financeiros tamb??m foram validados na regress??o em menor quantidade, o porte influenciou indicadores financeiros e direcionadores n??o financeiros, um conjunto b??sico, de direcionadores e indicadores formado pode ser vista como a que melhor se ajusta ?? incerteza ambiental e ao porte das empresas da amostra
199

Contabilidade ambiental : evidencia????o de eventos econ??micos de natureza ambiental pelas empresas do setor qu??mico e petroqu??mico

Oliveira, Robson de 29 August 2005 (has links)
Made available in DSpace on 2015-12-04T11:45:34Z (GMT). No. of bitstreams: 1 Robson_de_Oliveira.pdf: 643288 bytes, checksum: 18329e7e7b1f697d21ecb335826fcf40 (MD5) Previous issue date: 2005-08-29 / The companies, as integrant part of the society, are being forced to meet environmental goals, besides the economical ones, demonstrating that besides the economical return generated to the shareholders, they are also creating social return to the communities where they are located. Environmental Accounting is the system of information which main aim is to gather, measure and disclose the environmental transactions seeking to exercise the important role of communication vehicle between company and society. In this context, the accounting statements deserve attention and special study, regarding that they represent the main disclosure channel of economic-environmental items of which the Accounting uses. The objective of this work was to analyze a sample of accounting statements published in Brazil with the objective of verifying how the investments, liabilities and environmental costs have been disclosed. Unhappily, the accounting statements of this companies had revealed little adequate to the new necessities of the users of the accounting information, and parallel, insufficient to take care of to the requirements of NBC T 15 - Information of Social and Ambient Nature, approved for the Resolution of the Federal Advice of Accounting - CFC n?? 1.003, that it will enter in vigor from 1?? of January of 2006. / As empresas, como parte integrante da sociedade, est??o sendo fortemente demandadas a cumprirem metas ambientais, al??m das econ??micas; demonstrando que, al??m do retorno econ??mico gerado aos acionistas, tamb??m est??o gerando retorno social ??s comunidades em que se encontram inseridas. A Contabilidade Ambiental apresenta-se como o sistema de informa????es que tem como finalidade principal coletar, mensurar e evidenciar as transa????es ambientais visando a exercer o importante papel de ve??culo de comunica????o entre a empresa e a sociedade. Neste sentido, as demonstra????es cont??beis merecem aten????o e estudo especiais, haja vista que representam o principal canal de evidencia????o de itens econ??mico-ambientais do qual faz uso a Contabilidade. O objetivo deste trabalho foi o de analisar uma amostra de demonstra????es cont??beis publicadas no Brasil, das empresas Petrobr??s, Braskem, Refap, Copesul, Bunge Fertilizantes, Basf, Petroqu??mica Uni??o e OPP, todas do ramo qu??mico e petroqu??mico, no intuito de verificar como t??m sido evidenciados os investimentos, passivos e custos ambientais pelas referidas empresas. Infelizmente, as demonstra????es cont??beis dessas companhias mostraram-se pouco adequadas ??s novas necessidades dos usu??rios da informa????o cont??bil, e paralelamente, insuficientes para atender ??s exig??ncias da NBC T 15 - Informa????es de Natureza Social e Ambiental, aprovadas pela Resolu????o do Conselho Federal de Contabilidade - CFC n?? 1.003, que entrar?? em vigor a partir de 1?? de janeiro de 2006.
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Aplica??o da tecnologia eletroqu?mica como alternativa para a remo??o de corante t?xteis em efluentes sint?ticos e reais utilizando anodos de platina e diamante

Solano, Aline Maria Sales 14 July 2011 (has links)
Made available in DSpace on 2014-12-17T15:41:54Z (GMT). No. of bitstreams: 1 AlineMSS_DISSERT.pdf: 3248448 bytes, checksum: 238473f18fc530ccf887915ce75c940d (MD5) Previous issue date: 2011-07-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, electrochemical technology was used to treat synthetic wastewater containing Methyl Red (MR) and Blue Novacron (BN) by anodic oxidation using anodes platinum (Pt) and real samples of textile effluents using DDB anodes and platinum (Pt). The removal of color from the galvanostatic electrolysis of synthetic wastewater MR and BN, and the actual sample has been observed under different conditions (different current densities and temperature variation). The investigation of these parameters was performed in order to establish the best conditions for removal of color and chemical oxygen demand (BOD). According to the results obtained in this study, the electrochemical oxidation processes suitable for the degradation process of color and COD in wastewater containing such textile dyes, because the electrocatalytic properties of Pt and BDD anodes consumption energy during the electrochemical oxidation of synthetic solutions AN and MR and real sample, mainly depend on the operating parameters of operation, for example, the synthetic sample of MR, energy consumption rose from 42,00kWhm-3 in 40 mAcm-2 and 25 C to 17,50 kWhm-3 in 40mAcm-2 and 40 C, from the BN went 17,83 kWhm-3 in 40mAcm and 40?C to 14,04 kWhm- 3 in 40mAcm-2 and 40 C (data estimated by the volume of treated effluent). These results clearly indicate the applicability of electrochemical treatment for removing dyes from synthetic solutions and real industrial effluents / Neste trabalho, a tecnologia eletroqu?mica foi utilizada no tratamento de efluentes sint?ticos, contendo Vermelho de Metila (VM) e Azul de Novacron (AN), atrav?s da oxida??o an?dica utilizando ?nodos de Ti recoberto com platina (Ti/Pt). Ap?s isso, a fim de verificar a aplicabilidade do tratamento eletroqu?mico, amostras reais de efluentes t?xteis utilizando ?nodos de DDB e platina (Ti/Pt) foram tratadas eletroquimicamente visando a elimina??o completa dos corantes dissolvidos. A remo??o da cor a partir da eletr?lise galvanost?tica dos efluentes sint?ticos de VM e AN, e da amostra real tem sido observada em diferentes condi??es operacionais (diferentes densidades de corrente e varia??o da temperatura). A investiga??o destes par?metros foi realizada com o objetivo de estabelecer as melhores condi??es para remo??o da cor e da Demanda Qu?mica de Oxig?nio (DQO). De acordo com os resultados obtidos na realiza??o deste trabalho, o processo de oxida??o eletroqu?mica ? adequado para o processo de elimina??o da cor e da redu??o da DQO em efluentes que contenham esses corantes t?xteis, gra?as as propriedades eletrocatal?ticas dos ?nodos de DDB e Pt. O consumo de energia durante a oxida??o eletroqu?mica das solu??es sint?ticas contendo VM e AN e da amostra real depende principalmente das condi??es experimentais usadas, por exemplo, para a amostra sint?tica de VM, o consumo energ?tico passou de 42,00 kWhm-3 em 40 mAcm-2 e 25?C para 17,50 kWhm-3 em 40 mAcm-2 e 40?C; no entanto, o consumo de energia na eletr?lise do AN passou de 17,83 kWhm-3 em 40 mAcm-2 e 25?C para 14,04 kWhm-3 em 40 mAcm-2 e 40?C (dados estimados por volume de efluente tratado). Estes resultados indicam claramente a aplicabilidade de tal m?todo na remo??o de corantes dissolvidos em efluentes sint?ticos ou reais

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