Made available in DSpace on 2014-12-17T14:09:09Z (GMT). No. of bitstreams: 1 MichelleCF_TESE.pdf: 2764239 bytes, checksum: af9951c05c7267abaecbc91592b7596d (MD5) Previous issue date: 2010-03-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this study, it has been investigated the influence of silver film deposition onto 100% polyester woven and non-woven, on the survival of Escherichia coli and Staphylococcus aureus in contact with these surfaces. The treatment was performedin a chamber containing the working gas at low pressure (~ 10-2 mbar). Some process parameters such as as voltage: 470 V; pressure: 10-2 mbar; current : 0.40 A and gas flow: 6 and 10 cm3/min were kept constant. For the treatments with pur?argon plasma using a flow of 6 and 10 cm3/min, different treatment times were evaluated, such as, 10 , 20, 30, 40, 50 and 60 minutes. Contact angle (sessile drop), measurements were used to determine the surface tension of the treated fabrics and its influence on the bacteria grow as weel as the possibilities of a biofilm formation. The formation of a silver film, as well as the amount of this element was verified byEDX technique. The topography was observed through scanning electron microscopy (SEM) to determine the size of silver grains formed on the surfaces of the fabric and assess homogeneity of treatment. The X-ray diffraction (XRD) was used to analyze the structure of silver film deposition. The woven fabric treatments enabled the formation of silver particulate films with particle size larger than the non-woven fabrics. With respect to bacterial growth, all fabrics were shown to be bactericidal for Staphylococcus aureus (S. aureus), while for the Escherichia coli (E. coli), the best results were found for the non-woven fabric (TNT) treated with a flow of 10 cm3/min to both bacteria / Neste trabalho, investigou-se a influ?ncia da deposi??o de filme de prata em tecidos planos e tecido n?o tecido 100% poli?ster, sobre a sobreviv?ncia das bact?rias Escherichia coli e Staphylococcus aureus em contato com essas superf?cies. O tratamento foi realizado em uma c?mara contendo os gases de trabalho sob baixa press?o (~ 10-2 mbar) mantendo-se constante durante todo ensaio alguns par?metros do processo, tais como, voltagem: 470 V; press?o: 10-2 mbar; corrente: 0,40 A e fluxo de g?s: 6 e 10 cm3/min e diferentes tempos de tratamento: 10, 20, 30, 40, 50 e 60 minutos. Atrav?s do teste de ?ngulo de contato (gota s?ssil), foi determinada a tens?o superficial dos tecidos tratados e sua influ?ncia para com o crescimento de bact?rias e a poss?vel forma??o de um biofilme. A forma??o de um filme de prata, bem como a quantidade deste elemento foi verificada pela t?cnica deEDX. A topografia foi observada por Microscopia de Eletr?nica de Varredura (MEV), a fim de determinar o tamanho dos gr?os de prata formados sobre as superf?cies do tecido e analisar a homogeneidade do tratamento. A Difra??o de raios-X (DRX) foi utilizada para analisar a estrutura da prata depositada. Os tratamentos de tecidos planos propiciaram a forma??o de filmes de prata particulados com tamanho de part?culas maiores que os tecidos n?o tecidos. Com rela??o ? prolifera??o bacteriana, todos os tecidos mostraram-se bactericidas para a bact?ria Staphylococcus aureus (S. aureus), enquanto que para a bact?ria Escherichia coli (E. coli), os melhores resultados foram encontrados para o Tecido n?o tecido (TNT) tratados com fluxo de 10 cm3/min para ambas bact?rias

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-25T20:37:14Z No. of bitstreams: 1 GisellePereiraMoreira_DISSERT.pdf: 2433742 bytes, checksum: d2cf05db4d69f9db9774ee92c4f96457 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-26T23:11:44Z (GMT) No. of bitstreams: 1 GisellePereiraMoreira_DISSERT.pdf: 2433742 bytes, checksum: d2cf05db4d69f9db9774ee92c4f96457 (MD5) / Made available in DSpace on 2016-04-26T23:11:44Z (GMT). No. of bitstreams: 1 GisellePereiraMoreira_DISSERT.pdf: 2433742 bytes, checksum: d2cf05db4d69f9db9774ee92c4f96457 (MD5) Previous issue date: 2010-02-12 / Ag?ncia Nacional do Petr?leo - ANP / Este trabalho descreve a s?ntese e o estudo da aplica??o em fluido de perfura??o de um novo tensoativo (Tri-?ster Lipof?lico - TEL) obtido a partir de ?cido c?trico com octanol. A rea??o foi acompanhada por cromatografia em camada delgada (CCD) e o produto, ap?s a purifica??o, foi caracterizado por resson?ncia magn?tica nuclear de pr?ton e carbono (RMN H1 e C 13), an?lise termogravim?trica e de tens?o superficial em ?leo e ?gua. Atrav?s de testes comparativos com dois produtos comerciais usados em campo, avaliou-se o desempenho, como emulsificante, do TEL em fluidos ? base de ?ster, n-parafina e biodiesel de mamona nas raz?es ?leo/?gua (ROA) 70/30 e 60/40. Posteriormente, esses fluidos foram envelhecidos em estufa rotativa a 200 ?F durante 16 h, sendo ent?o realizadas medidas reol?gicas e de estabilidade el?trica a 135 ?F, separa??o de fase ap?s sete (7) dias em repouso e volume de filtrado em alta press?o e alta temperatura. O comportamento reol?gico foi avaliado a partir das curvas de fluxos. Observou-se, tamb?m, que estes apresentaram comportamento similares aos dos fluidos usados em campo (Binghamiano e pseudopl?stico com limite de escoamento). Os testes laboratoriais mostraram que o TEL reduziu o volume de filtrado e promoveu um aumento de estabilidade mec?nica e t?rmica. / This work describes the synthesis and study of the application of a new surfactant (Triester Lipophilic ? TEL) obtained by citric acid with octanol. It is reaction was followed by thin layer chromatography (TLC) and after purification the product was characterized by proton and 13 ? carbon nuclear magnetic resonance spectroscopy ( H and 13C NMR), thermogravimetric analysis (TGA) and surface tension analysis of oil-in-water emulsions. The TEL performance as surfactant in ester, n-paraffin and biodiesel based drilling fluids on the 70/30 and 60/40 water- oil rations (WOR) was evaluated by comparative tests of two commercial products used in the fields. These drilling fluids were aged in roller oven at 200 0 F during 16 h. The rheological and electric stability measurements were carried out at 135 ?F, the phase separation was evaluated after seven days at rest and the filtrate volume of drilling fluids was determined at high temperature and high pressure. The rheological behavior of the drilling fluids was evaluated by the flow curves. The results showed that the drilling fluids studied here presented Binghamian behavior as well as the used in the oil fields. The laboratory tests showed that the TEL reduced the filtrate volume and promoted the enhance of the thermal and mechanical stabilities.

Made available in DSpace on 2014-12-17T14:07:17Z (GMT). No. of bitstreams: 1 ThercioHCC.pdf: 966680 bytes, checksum: d8523389bd9b4ff916fa03cde47c7153 (MD5) Previous issue date: 2006-06-14 / A polyester film has a vast application field, due some properties that are inherent of this kind of material such as, good mechanical resistance, chemical resistance to acids and bases and low production cost. However, this material has some limitations as low superficial tension, flat surface, low affinity to dyers, and poor adhesion which impede the use of the same ones for some finality as good wettability. Among the existent techniques to increase the superficial tension, plasma as energy source is the more promising technique, because of their versatility and for not polluting the environment. The plasma surface polymeric modification has been used for many researchers, because it does not affect the environment with toxic agents, the alterations remains only at nanometric layers and this technique shows expressive results. Then, due to its good acceptance, polyester films were treated with oxygen plasma varying the treatment time from 10 to 60 min with an increase of 10 min to each subsequent treatment. Also, the samples were treated with a gas mixture (nitrogen + oxygen) varying the percentage of each gas the mixture from 0 to 100%, the treatment time remaining constant to all treatments (10 min). After plasma treatment the samples were characterized by contact angle, surface tension, Raman spectroscopy, Infrared attenuated total reflection (IR-ATR) and atomic force microscopy, with the aim to study the wettability increase of treated polyester films as its variables. In the (O2/N2) plasma treatment of polyester films can be observed an increase of superficial roughness superior to those treated by O2 plasma. By the other hand, the chemical modification through the implantation of polar groups at the surface is obtained more easily using O2 plasma treatment / Filmes de poli?ster possuem um vasto campo de aplica??o, devido algumas propriedades que s?o inerentes desse tipo de material, tais como boa resist?ncia mec?nica, resist?ncia qu?mica a ?cidos e bases e baixo custo de produ??o. Entretanto possuem limita??es, como baixa tens?o superficial, superf?cie n?o rugosa, pouca afinidade com corantes, e pouca ades?o, que impedem o uso dos mesmos para algumas finalidades principalmente quando esse uso requer que o material possua uma boa molhabilidade. Dentre as varias t?cnicas existentes para aumentar a tens?o superficial, as t?cnicas que utilizam o plasma, como fonte energ?tica, s?o as mais promissoras pela versatilidade e por n?o apresentar agentes nocivos ao meio. A modifica??o superficial de superf?cies polim?ricas por plasma tem sido bastante utilizada, pois a mesma n?o apresenta agentes nocivos ao ambiente, as altera??es promovidas no material s?o de escala nanom?tricas, e comprovadamente ? a t?cnica que tem apresentado resultados mais expressivos. Ent?o, tendo em vista a boa aceitabilidade do uso do plasma em materiais polim?ricos, tratou-se filmes de poli?ster usando plasma com atmosfera gasosa de oxig?nio variando-se o tempo de tratamento de 10 - 60 min com incremento de 10 min a cada tratamento subseq?ente, e tamb?m usou-se a atmosfera gasosa composta por uma mistura de nitrog?nio e oxig?nio, variando a concentra??o gasosa dos mesmos (de 0 100%), para um tempo de tratamento de 10 min. Ap?s o tratamento por plasma as amostras foram caracterizadas por medidas de ?ngulo de contato, tens?o superficial, espectroscopia Raman, Espectroscopia de infravermelho de reflex?o total atenuada (IR-ATR), e microscopia de for?a at?mica (AFM), onde foi caracterizado o aumento na molhabilidade dos filmes tratados por plasma bem como as vari?veis que contribu?ram para tal efeito. O Tratamento de filmes de poli?ster com a mistura de O2 e N2, apresenta uma rugosidade superficial das amostras superior a quando se utiliza somente O2 no tratamento com plasma. Por outro lado a modifica??o qu?mica, isto ?, a implementa??o de componentes qu?micos polares nas superf?cies das amostras ? obtido mais facilmente usando plasma com O2

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-04-11T19:42:50Z No. of bitstreams: 1 SuzanIalyGomesDeMedeiros_TESE.pdf: 1565131 bytes, checksum: fc1c6f25f300c374ed29471679c7076b (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-04-13T00:33:30Z (GMT) No. of bitstreams: 1 SuzanIalyGomesDeMedeiros_TESE.pdf: 1565131 bytes, checksum: fc1c6f25f300c374ed29471679c7076b (MD5) / Made available in DSpace on 2018-04-13T00:33:30Z (GMT). No. of bitstreams: 1 SuzanIalyGomesDeMedeiros_TESE.pdf: 1565131 bytes, checksum: fc1c6f25f300c374ed29471679c7076b (MD5) Previous issue date: 2012-09-04 / Enzimas t?m sido largamente utilizadas em bioss?ntese para transforma??es de compostos org?nicos em substitui??o aos m?todos sint?ticos cl?ssicos. Este trabalho descreve a s?ntese enzim?tica de biossurfactantes a partir da Dglicose com ?cido ricinol?ico empregando como biocatalisador a protease de Bacillus subtillis alcalina. Com aux?lio do software MODDE 7.0, o planejamento experimental utilizando um modelo fatorial 2 4-1 (planejamento reduzido de 2 n?veis e 4 vari?veis) foi realizado para verificar a influ?ncia das vari?veis temperatura, tempo de rea??o, concentra??o de enzima e raz?o molar do substrato/D-glicose sobre o rendimento da rea??o. An?lises de espectroscopia na regi?o do infravermelho (FTIR) confirmaram a forma??o do produto atrav?s de absor??es em 3400 cm-1, caracter?stica das hidroxilas presentes no anel do a??car, e em 1739 cm-1, correspondente ? carbonila de ?ster. As an?lises de CLAE (cromatografia l?quida de alta efici?ncia) mostraram as taxas de convers?es alcan?adas pelo biocatalisador protease de Bacillus subtillis alcalina. Medidas de tens?o superficial em diferentes condi??es, foram realizadas com o produto de rea??o, onde observou-se redu??o da tens?o superficial da ?gua de 72 mN/m para 33 mN/m. Foi poss?vel verificar tamb?m a estabilidade quanto do produto frente as solu??es salinas (115 g/L), nas solu??es tamp?o com pH extremos de 2 ? 12 e em solu??es aquosas aquecidas no intervalo de 25 a 100 ?C. Visando aplica??o do produto em t?cnicas Core-Flow (transporte de ?leo), an?lises de ?ngulo de contato pelo m?todo da placa de Willemy foram realizadas, obtendo-se a redu??o do ?ngulo de contato, do vidro com ?gua, de 40? para 0?. Nas an?lises como lubrificante e redutor de filtrado em fluidos de perfura??o polim?ricos observou-se, nas v?rias formula??es, que a mistura biodiesel/biossurfactante apresentou resultados satisfat?rios reduzindo o CL (coeficiente de lubricidade) em 87% e o volume de filtrado em 22%. Nos testes de forma??o e estabilidade de espuma, caracter?stica que deve ser evitada por proporcionar leituras incorretas (peso espec?fico, reologia, volumetria, etc), nenhum dos biossurfactantes teve a??o espumante caracterizando seu bom desempenho. / Enzymes have been widely used for organic compounds biosynthesis, attracting a great deal of attention in recent years, due to its several advantages over the chemical method. This work describes the enzymatic synthesis of biosurfactants from d-glucose with ricinoleic acid using proteases Bacillus subtillis alcalina as biocatalysts. Aiming to reach high conversions from substrates to products for a possible future large scale industrial production, a serie of variables was optimized, through MODDE 7.0, using the factorial model design 24-1. The investigated variables were: temperature, reaction time, enzyme concentration and substrate/D-glicose rate. Qualitative analysis by infrared spectroscopy (FTIR) confirmed the product formation through characteristic peaks due to hydroxyl group absorption on the sugar ring at 3400 cm-1 and the carbonyl group at 1739 cm-1, which refers to ester carbonyl. HPLC analysis (High Performance Liquid Chromatography) showed higher conversions using of alkaline protease of Bacillus subtillis. Besides, it was observed that all the biosurfactants reduced the surface tension of water from 72 to 33 mN/m (by interpolate of the plate method). According to surface tension results, it was possible to evaluate the stability of each product about saline (maximum 115g/L) and buffer solutions (pH 2 ? 12), from a temperature range from 25 to 100?C). Aiming its application to core-flow technique, contact angle measurements presented reduction of 40? to 0? in presence of d-glucose ricinoleate, when compared to distillated water. Different applications of this product were investigated, such as: lubricant and filter loss control for polymeric drilling fluids of petroleum wells. It was observed the reduction of lubricity coefficient and filtrate loss control in 87 and 22 %, respectively.

Made available in DSpace on 2014-12-17T14:07:03Z (GMT). No. of bitstreams: 1 ThercioHCC_TESE.pdf: 3355689 bytes, checksum: 0848bf4db8c96f8922893ef41d7b36f0 (MD5) Previous issue date: 2010-03-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work reports the influence of the poly (ethylene terephthalate) textile and films surface modification by plasmas of O2 and mixtures (N2 + O2), on their physical and chemical properties. The plasma surface polymeric modification has been used for many researchs, because it does not affect the environment with toxic agents, the alterations remains only at nanometric layers and this technique shows expressive results. Then, due to its good acceptance, the treatment was carried out in a vacuum chamber. Some parameters remained constant during all treatment, such as: Voltage 470 V; Pressure 1,250 Mbar; Current: 0, 10 A and gas flow: 10 cm3/min, using oxygen plasma alternating the treatment time 10 to 60 min with an increase of 10 min to each subsequent treatment. Also, the samples were treated with a gas mixture (nitrogen + oxygen) which was varied only the gas composition from 0 to 100% leaving the treatment time remaining constant to all treatment (10 min). The plasma treatment was characterized in-situ with Optics Emission Spectroscopy (OES), and the samples was characterized by contact angle, surface tension, Through Capillary tests, Raman spectroscopy, Infrared attenuated total reflection (IR-ATR) and atomic force microscopy, scanning electronic Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS). The results showed that oxygen treated fabrics presented high wettability, due to the hydrophilic groups incorporation onto the surface formed through spputering of carbon atoms. For the nitrogen atmosphere, there is the a film deposition of amine groups. Treatment with small oxygen concentration in the mixture with nitrogen has a higher spputered species of the samples / Neste trabalho, investigou-se a influ?ncia do tratamento superficial a plasma utilizando como gases de trabalho o oxig?nio e uma mistura de nitrog?nio + oxig?nio, sobre as propriedades f?sicas e qu?micas de tecidose filmes de Poli?ster. A modifica??o superficial de superf?cies polim?ricas por plasma tem sido bastante utilizada, pois a mesma n?o apresenta agentes nocivos ao ambiente, ?s altera??es promovidas no material s?o de escala nanom?tricas, e comprovadamente ? a t?cnica que tem apresentado resultados mais expressivos. Ent?o, tendo em vista a boa aceitabilidade do uso do plasma em materiais polim?ricos, O tratamento foi realizado em uma c?mara contendo os gases de trabalho sob baixa press?o (~ 1 mbar) mantendo-se constante durante todo ensaio alguns par?metros do plasma, tais como, voltagem: 470 V; press?o: 1,250 mbar; corrente: 0,10 A e fluxo de g?s: 10 cm3/min, usando plasma com atmosfera gasosa de oxig?nio variando-se o tempo de tratamento de 10 - 60 min com incremento de 10 min a cada tratamento subseq?ente, e tamb?m usou-se a atmosfera gasosa composta por uma mistura de nitrog?nio e oxig?nio, variando a concentra??o gasosa dos mesmos (de 0 100%), para um tempo de tratamento de 10 min. O tratamento por plasma foi caracterizado in-situ com o auxilio da Espectroscopia de Emiss?o ?tica,e as amostras foram caracterizadas por medidas de ?ngulo de contato, tens?o superficial, arraste capilar, espectroscopia Raman, Espectroscopia de infravermelho de reflex?o total atenuada (IR-ATR), e microscopia de for?a at?mica (AFM), Microscopia Eletr?nica de Varredura (MEV) e por espectroscopia de fotoel?trons excitados por raios-X (XPS). Os resultados mostraram que tecidos tratados com atmosfera de oxig?nio apresentaram elevada molhabilidade, devido a incorpora??o de grupos hidrof?licos na superf?cie formados com o arrancamento de ?tomos de carbono. Para a atmosfera de nitrog?nio, tem-se a deposi??o de um filme com base em em grupos aminas. Tratamentos com a concentra??o pequena de Oxig?nio numa mistura com Nitrog?nio tem-se maior arrancamento de esp?cies das amostras

Made available in DSpace on 2014-12-17T14:57:52Z (GMT). No. of bitstreams: 1 DucianeOF.pdf: 2916882 bytes, checksum: 4dd79fd7f32c69ce44eb80c291049409 (MD5) Previous issue date: 2009-08-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The 100% cotton fabric (CO)* treated with plasma of methane CH4 has direct application in all areas that needs of aqueous solutions repellent material like coatings and uniforms applied biomedical, aeronautics, and automobile between others. 100% cotton fabric (CO) samples were treated by plasma with two differents atmosphere: Methane gas (CH4), treatment time was varied in 10 in 10 min. until 60 min., and mixture methane/argon (CH4/Ar), it was varied the proportion 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, with treatment time of 30 minutes. In both, the fluxe was 5 sccm (second cubic centimeter), pressure 6 mbar, voltage 490 V and current 0,15A. The objective of work was measure the superficial tension of 100% CO then it treated with plasma, using contact angle measures of water and glycerol with the surface. The samples were tested after treatment, with 8 and 12 months to verify the superficial modification effects. It was verified an increase of hydrophobility with the Sessile drop values varied between 116,69? to 137,85? and it carried on after 12 months. The no treated samples shows contact angle equal 0?. OES analysis and Raman spectroscopy were accomplished. In the SEM analysis was verified oligomers. The plasma treatment is correct environmental, It turning greater than conventional treatments / O tecido 100% Algod?o (CO)* tratado com plasma de metano (CH4) tem aplica??o direta em todas as ?reas que necessitam de um material com maior repel?ncia a solu??es aquosas, como revestimentos e uniformes aplicados a ?rea biom?dica, aeron?utica, automobil?stica, entre outras. Amostras de tecido 100% CO foram tratadas com plasma utilizando duas atmosferas diferentes: g?s CH4, com tempos que variaram de 10 em 10 min. at? 60 min., e uma mistura de metano/arg?nio (CH4/Ar), em propor??es 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, durante 30 min. O fluxo utilizado nos dois processos foi de 5 cm3/s (cent?metro c?bicos por segundo), a uma press?o de 6 mbar , voltagem de 490 V e corrente de 0,15 A. O objetivo do trabalho foi medir a varia??o da tens?o superficial do tecido 100% CO ap?s tratado com plasma; Utilizando medidas de ?ngulo de contato da ?gua e do glicerol com a superf?cie. As amostras foram testadas imediatamente ap?s o tratamento, com 8 e 12 meses, a fim de verificar a dura??o do efeito desta modifica??o superficial. Verificou-se um aumento da hidrofobicidade atrav?s dos valores do teste da gota s?ssil que variaram entre 116,69? a 137,85? e se mantiveram ap?s 12 meses; As amostras n?o tratadas apresentam ?ngulo de contato igual a 0?. An?lises de espectroscopia de emiss?o ?tica (EEO) e espectroscopia Raman (ER) foram realizadas, bem como, an?lise de microscopia eletr?nica de varredura (MEV) a qual confirmou presen?a de olig?meros. O processo a plasma ? ambientalmente correto e se torna superior em compara??o aos tratamentos convencionais