Submitted by Laryssa Kataki De Oliveira Veloso (laryssakataki@hotmail.com) on 2018-06-15T13:25:57Z No. of bitstreams: 1 DISSERTAÇÃO LARYSSA FINAL.pdf: 1251310 bytes, checksum: 43a08fca6a961ece3b6833de3671f737 (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-06-18T20:28:55Z (GMT) No. of bitstreams: 1 veloso_lko_me_bot.pdf: 1251310 bytes, checksum: 43a08fca6a961ece3b6833de3671f737 (MD5) / Made available in DSpace on 2018-06-18T20:28:55Z (GMT). No. of bitstreams: 1 veloso_lko_me_bot.pdf: 1251310 bytes, checksum: 43a08fca6a961ece3b6833de3671f737 (MD5) Previous issue date: 2018-05-30 / OBJETIVO: Avaliar a eficiência da injeção de ácido hialurônico (AH) ou de soro fisiológico (SF), aplicados no subcutâneo da pálpebra inferior de portadores de ectrópio cicatricial, visando à correção não cirúrgica do mal posicionamento palpebral. MÉTODOS: este foi um estudo prospectivo, intervencionista, envolvendo 23 pálpebras de 15 portadores de ectrópio cicatricial, divididos aleatoriamente em dois grupos: G1 (13 pálpebras) no qual foram feitas quatro aplicações de 4ml de SF (Cloreto de Sódio 0,9%, Equiplex, Goiás, Brasil), associado a 1ml de cloridrato de lidocaína a 2,0% sem vasoconstritor (Xylestesin®, Cristália, São Paulo, Brasil), em intervalos de uma semana entre as aplicações; e G2 (10 pálpebras) que receberam aplicação de 1 ml de AH (Restylane® Lidocaine, Q med, Uppsala, Suécia) em aplicação única. Foram avaliadas as variáveis demográficas dos participantes, as queixas, o grau do ectrópio, o grau de flacidez palpebral, a localização do ectrópio, além de avaliações quantitativas realizadas utilizando-se a fotodocumentação sistematizada dos olhos dos pacientes, 30 dias após a primeira aplicação no G1 e 7 e 30 dias após as aplicações do G2. As imagens obtidas foram transferidas para um computador e avaliadas utilizando-se o programa Image J, avaliando-se a distância da pálpebra inferior até o reflexo corneano (DMR2), distância limbo-margem (LM), ângulo da comissura interna (AI) e externa (AE), área total (AT), lateral (AL) e medial (AM). As áreas a serem avaliadas foram delimitadas por uma linha que une as duas comissuras e outra linha que coincide com a margem da pálpebra inferior. As avaliações foram feitas sem tração e com tração da pálpebra inferior para baixo. Todos os dados foram transferidos para a planilha Excel, sendo realizada a análise comparativa antes e após as aplicações nos dois grupos. RESULTADOS: Os grupos foram semelhantes quanto a idade, sexo, cor da pele e grau do ectrópio. Houve melhora signficativa dos sintomas nos indivíduos de G2 após a aplicação de AH. Apos a injeção, o G1 apresentou redução significativa de AI com e sem tração, AE com tração, LM sem tração e AM com tração. No G2, após as injeções as medidas AI sem tração, AE, DMR2, AT e AM com e sem tração, LM e AL com tração apresentaram alterações significativas (p<0,05). A comparação das medidas realizadas no G2 após sete e 30 dias mostrou estabilidade dos resultados obtidos com a injeção de AH. CONCLUSÃO: A aplicação de AH na pálpebra inferior de portadores de ectrópio cicatricial mostrou melhora parcial do mal posicionamento palpebral. A aplicação de SF não foi efetiva no tratamento do ectrópio cicatricial. / PURPOSE: Evaluate the efficiency of injection of hyaluronic acid (HA) or saline solution (SF) applied to the lower eyelid subcutaneous, aiming at the non-surgical correction of cicatricial ectropion. METHODS: This was a prospective study involving 23 eyelids of 15 patients with cicatricial ectropion, randomly divided into two groups: G1 (13 eyelids) with four applications of 4ml of SF (Sodium Chloride 0.9%, Equiplex, Goiás , Brazil), associated to 1ml of lidocaine hydrochloride 2% without vasoconstrictor (Xylestesin®, Cristália, São Paulo, Brazil), with a one-week interval between applications; and G2 (10 eyelids) which received single application of 1 ml of AH (Restylane® Lidocaine, Q med, Uppsala, Sweden). Demographic variables, complaints, ectropion degree, eyelid flaccidity degree, ectropion location, and quantitative assessments using the systematized photodocumentation of patients eyelids 30 days after the first application in G1 and 7 and 30 days after applications in G2 were studied. The images were transferred to a computer and evaluated using the Image J program and the distance between the lower eyelid margin to corneal reflex (DMR2), limbus margin distance (LM), internal angle (IA) and external angle (EA), total (TA), lateral (LA) and medial areas (MA) were analyzed. The area measurements were delimited by a line between the two commissures and along the lid margin of the lower eyelid. The evaluations were done without traction and with traction downward of the lower eyelid. All data were transferred to the Excel spreadsheet and comparative analysis was performed before and after the applications in the two groups. RESULTS The groups were similar according to age, sex, skin color and degree of ectropion. There was a significant improvement in G2 individuals after the application of AH. After injections G1 presented a significant reduction of AI with and without traction, EA with traction, LM without traction and AM with traction. The G2 after injections showed AI measurements without traction, EA, DMR2, TA and MA with and without traction, LM and LA with traction with significant alterations (p <0.05). The comparison of the G2 measurements obtained after 7 and 30 days showed stability of the results obtained with the AH injection. CONCLUSION: The application of AH in the lower eyelid of patients with cicatricial ectropion resulted in partial improvement of palpebral malposition. The application of SF was not effective in the treatment of cicatricial ectropion.

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Made available in DSpace on 2014-12-17T14:58:25Z (GMT). No. of bitstreams: 1 EylissonAS.pdf: 1489335 bytes, checksum: 8fcffdaaafca0f8691545bd2bc5dd5fc (MD5) Previous issue date: 2007-07-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / With the current growth in consumption of industrialized products and the resulting increase in garbage production, their adequate disposal has become one of the greatest challenges of modern society. The use of industrial solid residues as fillers in composite materials is an idea that emerges aiming at investigating alternatives for reusing these residues, and, at the same time, developing materials with superior properties. In this work, the influence of the addition of sand, diatomite, and industrial residues of polyester and EVA (ethylene vinyl acetate), on the mechanical properties of polymer matrix composites, was studied. The main objective was to evaluate the mechanical properties of the materials with the addition of recycled residue fillers, and compare to those of the pure polyester resin. Composite specimens were fabricated and tested for the evaluation of the flexural properties and Charpy impact resistance. After the mechanical tests, the fracture surface of the specimens was analyzed by scanning electron microscopy (SEM). The results indicate that some of the composites with fillers presented greater Young s modulus than the pure resin; in particular composites made with sand and diatomite, where the increase in modulus was about 168 %. The composites with polyester and EVA presented Young s modulus lower than the resin. Both strength and maximum strain were reduced when fillers were added. The impact resistance was reduced in all composites with fillers when compared to the pure resin, with the exception of the composites with EVA, where an increase of about 6 % was observed. Based on the mechanical tests, microscopy analyses and the compatibility of fillers with the polyester resin, the use of industrial solid residues in composites may be viable, considering that for each type of filler there will be a specific application / Com o crescimento acelerado do consumo de produtos industrializados, principalmente de produtos descart?veis, o aumento excessivo de lixo e sua disposi??o em lugares inadequados tornaramse um dos grandes problemas da sociedade moderna. A utiliza??o de res?duos s?lidos industriais como carga em comp?sitos ? uma id?ia que surge com o intuito de buscar alternativas adequadas para o reaproveitamento desses res?duos, visando tamb?m o desenvolvimento de materiais com propriedades superiores ?quelas dos materiais convencionais. Neste trabalho, estudouse a influ?ncia da adi??o de res?duos industriais de poli?ster e EVA (Etileno Acetato de Vinila), al?m de cargas de areia e diatomita, nas propriedades mec?nicas de comp?sitos de matriz poli?ster. O principal objetivo foi avaliar o comportamento mec?nico desses materiais com a adi??o de cargas de res?duo industrial, comparandoos com as propriedades da resina pura. Corposdeprova foram confeccionados e as propriedades mec?nicas dos comp?sitos obtidos foram analisadas, atrav?s de testes de flex?o e de impacto. Ap?s os ensaios mec?nicos, a superf?cie de fratura dos corposdeprova foi analisada por microscopia eletr?nica de varredura (MEV). Os resultados dos ensaios de flex?o mostraram que alguns comp?sitos apresentaram maior m?dulo, quando comparados com os resultados da resina pura; com destaque para os confeccionados com areia e diatomita, em que o aumento do m?dulo chegou a 168 %. Os comp?sitos confeccionados com adi??o de poli?ster e de EVA apresentaram m?dulo mais baixo que o da resina pura. Tanto o limite de resist?ncia quanto ? deforma??o m?xima, apresentaram redu??o nos seus valores, quando da adi??o de cargas. A resist?ncia ao impacto, em rela??o ? resina pura, foi reduzida em todos os comp?sitos com adi??o de cargas, exceto nos comp?sitos com a adi??o de EVA, onde houve um aumento de aproximadamente 6 %. Com base nos ensaios mec?nicos realizados, nas an?lises microsc?picas e na compatibilidade das cargas com a resina poli?ster, a utiliza??o das cargas de res?duos s?lidos industriais em comp?sitos mostrouse vi?vel, considerando que para cada tipo de carga haver? uma aplica??o espec?fica

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Ce travail de thèse porte sur l'incorporation de charges minérales d'oxyde d'erbium, Er2O3, et d'oxyde de praséodyme, Pr6O11, dans une matrice polymère de type élastomère, ceci dans le cadre d'un projet industriel de remplacement du plomb dans des équipements de radioprotection. L'objet de cette thèse était d'améliorer la dispersion des charges au sein de la matrice par le biais de procédés de traitements chimiques de ces particules. Divers types de fonctionnalisations de surface ont été employés afin de compatibiliser celles-ci avec une matrice organique, notamment par greffage de composés de type acides phosphoniques. Plusieurs acides phosphoniques ont ainsi pu être utilisés avec succès pour la fonctionnalisation des deux types de charges. La caractérisation de ces différentes fonctionnalisations représente une part importante de ce projet. Des techniques d'analyse innovantes, aussi bien directes qu'indirectes ont été employées dans ce but, à savoir de la Py-GC/MS pour la détection des composés ancrés à la surface des charges, de la fluorescence X et de la spectroscopie infrarouge dans un objectif de quantification, mais aussi des études cinétiques de sédimentation des charges dans un milieu liquide organique. Finalement, des composites ont pu être obtenus par mélange des charges, traitées et non traitées, avec une matrice polyuréthane. Des essais de traction ont permis de montrer clairement une amélioration des propriétés mécaniques de certains des composites, grâce à la fonctionnalisation des charges par les acides phosphoniques. / This thesis focuses on the incorporation of mineral fillers of erbium oxide, Er2O3, and praseodymium oxide, Pr6O11, in an elastomeric polymer matrix, in the context of an industrial project to replace the lead in radiation protection equipment. The actual purpose of this thesis was to improve the dispersion of the fillers in the matrix through chemical treatment processes of these particles. Various types of surface functionalization were used to compatibilize them with an organic matrix, in particular by grafting compounds such as phosphonic acids. Hence, several phosphonic acids have been successfully used for the functionalization of both types of fillers. The characterization of these functionalizations is an important part of this project. Innovative analysis techniques, both direct and indirect have been used for this purpose, namely Py-GC/MS to detect the chemical compounds anchored to the surface of the fillers, X-ray fluorescence and FTIR spectroscopy with a quantification target, but also a study of sedimentation kinetics of the fillers in an organic medium. Finally, composites were obtained by mixing the fillers, untreated and treated, with a polyurethane matrix. Tensile tests have clearly shown an improvement of mechanical properties for some of the composites, due to the functionalization of the fillers by phosphonic acids.

Dans les industries automobile et aéronautique, les opérations de finition des pièces métalliques sont souvent réalisées avec des bandes abrasives ; on parle alors de « toilage ». Lors des opérations de toilage à sec des aciers, les conditions à l’interface entre l’outil abrasif et la pièce métallique usinée sont très sévères en termes de pression et de température. Un transfert métallique, communément appelé « chargement métallique » est observé à la surface des grains abrasifs en céramique de la bande abrasive, entrainant une chute de ses performances de coupe. L’objectif de ce travail est de comprendre ce phénomène de chargement métallique et notamment de mettre en évidence les paramètres l’influençant. L’effet de la nature des grains, de la nature des aciers ou encore de la présence de charges actives dans la bande abrasive ont donc été étudié. Une étude a donc été réalisée à différentes échelles : à l’échelle globale du contact bande abrasive / métal sur un dispositif industriel de toilage, puis à l’échelle plus locale du contact entre la céramique (du grain abrasif) et du métal, grâce à un dispositif tribologique adapté. Des caractérisations physico-chimiques par XPS (X-Ray Photoelectron Spectroscopy) et TEM-EDX (Transmission Electron Microscopy couplée avec la spectroscopie Energy Dispersive X-ray) des bandes abrasives ont également été réalisées. L’influence des charges actives, produits fluorés ajoutés à la résine de la bande abrasive, sur l’adhésion du métal sur le grain céramique a ainsi été mise en évidence, notamment dans le cas de l’acier inoxydable 304 où le chargement métallique a été fortement limité. Les mécanismes d’action de ces charges actives sont ensuite discutés. / In automotive and aeronautic industries, grinding operations can sometimes be done with abrasive belts. During dry metal grinding, conditions at the interface between the abrasive tool and the metal workpiece are very hard in terms of pressure and temperature. Metal transfer, known as “metal capping”, is observed at the surface of the abrasive ceramic grain inducing a drop in the cutting efficiency. The objective of this work is to understand this metal capping phenomenon and to highlight the parameters which have an influence on it. The effects of abrasive grain nature, metal nature or active filler presence in the abrasive belt are then studied. A study has been done at different scales: at the global scale of the abrasive belt / metal contact thanks to an industrial grinding test, and then at the more local scale of the contact between ceramic (from the abrasive grain) and metal, thanks to a suitable tribological device. Physicochemical characterizations by XPS (X-Ray Photoelectron Spectroscopy) and TEM-EDX (Transmission Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy) were carried out on worn abrasive belts. The influence of the active fillers – fluorinated products added in the resin of the abrasive belt – on metal adhesion on the ceramic grain was then observed, especially in the case of the 304 stainless steel grinding where metal capping was significantly reduced. Action mechanisms of these active fillers were finally discussed.

No description available.

[ES] La presente Tesis Doctoral se ha centrado en el aislamiento y caracterización de materiales celulósicos y extractos activos, procedentes de las cascarillas de arroz y café, y su incorporación a películas de almidón y mezclas compatibilizadas de almidón-PLA, para mejorar sus propiedades funcionales como materiales para el envasado de alimentos. Las fibras de celulosa (CF) se obtuvieron mediante tratamiento alcalino y de blanqueo, con un rendimiento de 41 y 53 g fibras/100 g cascarilla, respectivamente para cascarilla de arroz y café. Los nanocristales de celulosa (CNC) se aislaron de las fibras mediante hidrólisis ácida, con un rendimiento del 5% respecto a las fibras y con alta cristalinidad (90-92%), resistencia térmica y relación de aspecto (L/d: 20-40). Los compuestos activos se obtuvieron mediante extracción hidrotérmica (180 ºC; 9,5 bares), con un rendimiento de 17-18 g/ 100 g de cascarilla. Dichos extractos exhibieron capacidad antioxidante (EC50: 5,37-5,29 mg sólidos extraídos/ mg DPPH) y antimicrobiana (cuantificada en términos de concentración mínima inhibitoria: MIC) frente a L. innocua (MIC: 48-52 mg polvo/mL) y E. coli (MIC: 50-66 mg polvo/mL). Los materiales celulósicos procedentes de cascarilla de arroz y café se incorporaron a películas de almidón termoplástico (TPS), obtenidas mediante mezclado en fundido y moldeo por compresión. El módulo elástico aumentó un 186 y 121% cuando se incorporó a la matriz un 1% (p/p) de CNC de cascarilla de arroz y café, respectivamente. Del mismo modo, las CF se añadieron a las películas de TPS al 1, 5 y 10 pt%. Ambas CF aumentaron la rigidez y redujeron la extensibilidad de los films, aunque las CF de cascarilla de café mantuvieron mejor la ductilidad al 1 y 5% (p/p). La permeabilidad al vapor de agua de las películas de TPS no se redujo en los materiales compuestos, aunque la permeabilidad al oxígeno se redujo en aproximadamente un 17%. Al incorporar extractos activos a los films de almidón, mejoraron sus propiedades de tracción; el módulo elástico aumentó un 350%, a la vez que se hicieron menos extensibles. Las fibras de celulosa de ambos residuos fueron más efectivas como agentes de refuerzo en los films con extractos sólidos que en los de almidón solo. Se estudiaron también mezclas de almidón-PLA utilizando como compatibilizador policaprolactona funcionalizada con anhídrido maléico y/o glicidil metacrilato (PCLMG o PCLG). Se analizó el efecto de la proporción de PLA en la mezcla (20 y 40% respecto al almidón), y la de ambos compatibilizadores (2,5 y 5%), en las propiedades de los films. Los análisis de la microestructura, el comportamiento térmico y las propiedades funcionales (mecánicas, ópticas y de barrera) de los films, demostraron que sustituir el 20% del almidón por PLA e incorporar el 5% de PCLG podría ser una buena estrategia para obtener materiales adecuados para envasado de alimentos. Además, se estudió el efecto de la adición de rellenos celulósicos (CF y CNC) y del extracto antioxidante de cascarilla de café en la mezcla de almidón-PLA compatibilizada seleccionada. Las propiedades antioxidantes de los films se probaron a través de su eficacia para preservar al aceite de girasol de la oxidación. Se observaron diferencias significativas en las propiedades funcionales de los films cuando los CNC se incorporaron mediante dos métodos diferentes. El efecto de refuerzo de los materiales celulósicos en mezclas de S-PLA fue menos notable que en las películas de almidón, probablemente debido a la superposición del efecto de refuerzo de PLA. El extracto antioxidante no mejoró el comportamiento mecánico en la mezcla, pero le confirió capacidad antioxidante, adecuada para aplicaciones en el envasado de alimentos. / [CAT] La present Tesi Doctoral s'ha centrat en l'aïllament i caracteritzaciò de materials cel.lulòsics i extractes actius, procedents de pellorfa d'arròs i café, i la seua incorporació a pel·lícules de midó i mescles compatibilitzades de midò-PLA, per a millorar les seues propietats funcionals com materials per al envasat d'aliments. Les fibres de cel.lulosa (CF) s'obtingueren mitjançant tractament alcalí i de blanqueig, amb un rendiment de 41 i 53 g fibres/100g pellorfa, respectivament per a pellorfa d'arròs i cafè. Els nanocristalls de cel·lulosa (CNC) es van aïllar de les fibres de cel·lulosa per mig d'hidròlosi àcida, amb un rendiment del 5% respecte a les fibres; en tots dos casos, amb alta cristal·línitat (90-92%), resistència tèrmica i relaciò d'aspecte (L/d: 20-40). Els composts actius s'obtingueren mitjançant l'extracció hidrotèrmica (180 ºC; 9,5 bars), amb un rendiment del 17-18 g/100 g de pellorfa. Aquests composts exhibiren capacitat antioxidant (EC50: 5,37-5,29 mg extracte solit/ mg DPPH) i antimicrobiana, (quantificada en termes de concentració mínima inhibitòria: CMC) enfront a L. innocua (MIC: 48-52 mg pols/mL) i E. coli (MIC: 50-66 mg pols/ mL). Els materials cel·lulòsics procedents de pellorfa d'arròs i cafè es van incorporar a pel·lícules de midó termoplàstic (TPS), obtingudes mitjançant mesclat en fos i modelatge per compressió. El mòdul elàstic va augmentar un 186 i 121% quan es va incorporar a la matriu un 1 pt% CNC de pellorfa d'arròs i café, respectivament. De la mateixa manera, les CF es van afegir a les pel·lícules de TPS al 1, 5 i 10 pt%. Ambdues CF va augmentar la rigidesa de les pel·lícules i es va reduir la seua capacitat d'estirament. No obstant, les CF de pellorfa de cafè mantingueren millor la ductilitat al 1 i 5%. La permeabilitat al vapor d'aigua de les pel·lícules de TPS no es va reduir en els materials compostos, encara que la permeabilitat a l'oxigen es va reduir en aproximadament un 17%. A l'incorporar extractes actius a les pel·lícules de midó, milloraren les propietats de tracció de les pel·lícules ; el mòdul elàstic va augmentar un 350%, mentre que les pel·lícules es feren menys extensibles. Les CF dels dos residus foren més efectives com agents de reforç en pel·lícules que contenien extractes actius, que en pel·lícules de midó pur. També es van estudiar mescles de midò-PLA utilitzant com a compatibilitzador policaprolactona funcionalitzada amb anhídrid maleic i/o glicidil metacrilat (PCLMG o PCLG). Es va analitzar l'efecte de la proporció de PLA en la mescla (20 i 40% respecte al midó), i de la tots dues compatibilitzadors (2,5 i 5%), en les propietats de les pel·lícules. Els anàlisis de la microestructura, el comportament tèrmic i les propietats funcionals (mecàniques, óptiques i de barrera) de les pel·lícules, demostraren que substituir el 20% del midó per PLA i incorporar el 5% de PCLG podria ser una bona estratègia per a obtindré pel·lícules adequades per a l'envasat d'aliments. A demés, es va estudiar l'efecte de l'addició de reforçaments cel·lulòsics (CF i CNC) i extracte antioxidant de pellorfa de cafè, en mescles de midó-PLA compatibilitzades. Les propietats antioxidants de les pel·lícules s'analitzaren a través de la seua eficàcia per a preservar de l'oxidació l'oli de gira-sol. S'observaren diferències significatives en les propietats funcionals de les pel·lícules quan els CNC s'incorporaren mitjançant dos mètodes diferents. L'efecte de reforç dels materials cel·lulòsics en mescles de S-PLA va ser menys notable que en les pel·lícules de midó, provablement degut a la superposició de l'efecte de reforç del PLA. L'extracte antioxidant no va millorar el comportament mecànic en les mescles, però li va conferir la capacitat antioxidant adequada per a aplicacions a l'envasat d'aliments. / [EN] This Doctoral Thesis has focused on the isolation and characterisation of cellulosic materials and active extracts from coffee and rice husks, and their incorporation into starch films and starch-PLA compatibilised blend films in order to improve their functional properties as food packaging materials. Cellulose fibres were obtained through alkali and bleaching treatment with a final yield of 41 and 53 g fibres/100 g husk, respectively for rice and coffee husks. Cellulose nanocrystals were isolated from the bleached fibres by acid hydrolysis, with a yield of 5% with respect to bleached fibres, in both cases, with high crystallinity (90-92%), thermal resistance and aspect ratio (L/d: 20-40). The active compounds were obtained by hydrothermal extraction (180 ºC, 9.5 bar) with yields of 17 -18 g/100 g husks. They exhibited antioxidant properties (EC50: 5.37-5.29 mg extract solids/mg DPPH) and antibacterial activity against L. innocua (MIC: 48-52 mg powder/mL) and E. coli (MIC: 50-66 mg powder/mL), which were quantified in terms of the minimal inhibitory concentration. Cellulosic material from rice and coffee husks were incorporated into thermoplastic starch films (TPS) by melt blending and compression moulding. The elastic modulus increased by 186 and 121% when 1 wt% of cellulose nanocrystals (CNC) from rice and coffee husks, respectively, was incorporated into the matrix. Likewise, cellulose fibres (CF) were incorporated into TPS films at 1, 5 and 10 wt%. Both CF increased the film stiffness while reducing its stretchability. However, CF from coffee husk better maintained the film ductility at 1 and 5 wt%. The water vapour permeability of TPS films was not reduced in composites, although oxygen permeability was lowered by about 17%. When active extracts were incorporated into starch films, they improved the tensile properties; the elastic modulus increased by about 350%, while films became less stretchable. The cellulosic fibres from both residues were more effective as reinforcing agents in films containing extract solids than in net starch films. Starch-PLA blend films were also studied using grafted polycaprolactone with maleic anhydride and/or glycidyl methacrylate (PCLMG or PCLG) as compatibilisers. The effect of both the PLA ratio in the blend (20 and 40% with respect to starch) and the amount of both compatibilisers (2.5 and 5%) on the film properties was analysed. The analyses of microstructure, thermal behaviour and functional properties (mechanical, optical and barrier) of the films led to the conclusion that substituting 20% of the starch by PLA, and incorporating 5% of PCLG would be a good strategy to obtain films suitable for food packaging. The effect of the addition of cellulosic fillers (CF and CNC) and antioxidant aqueous extract from coffee husk to compatibilised starch-PLA blends was also studied. The antioxidant properties of the films were tested through their efficacy at preserving sunflower oil from oxidation. Significant differences were observed in the functional properties of the films when CNC was incorporated by two different methods. The reinforcing effect of cellulosic materials in S-PLA blends was less noticeable than in starch films, probably due to the overlapping of the PLA reinforcing effect. The antioxidant extract did not improve the mechanical performance in the blends, but conferred antioxidant capacity suitable for food packaging applications. / Collazo Bigliardi, S. (2019). Lignocellulosic fractions from rice and coffee husks to improve functionality of biodegradable films based on starch and poly-lactic acid [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/123055 / TESIS

A commercial epoxy was modified by adding fluorinated poly (aryl ether ketone) and in turn metal micro powders (Ni, Al, Zn, and Ag) and coated on mild steel. Two curing agents were used; triethylenetetramine (curing temperatures: 30 oC and 70 oC) and hexamethylenediamine (curing temperature: 80 oC). Variation in tribological properties (dynamic friction and wear) and surface energies with varying metal powders and curing agents was evaluated. When cured at 30 oC, friction and wear decreased significantly due to phase separation reaction being favored but increased when cured at 70 oC and 80 oC due to cross linking reaction being favored. There was a significant decrease in surface energies with the addition of modifiers.

Hot mix asphalt pavements require adequate compaction to achieve the required density to resist rutting. The amount of energy required to achieve the optimum degree of compaction depends on the type of gradation, bitumen content, filler type and shape, type of compaction equipment etc. In this study, the net energy required to reduce the specimen volume (size) after each gyration of the superpave gyratory compactor is used as the compaction energy index (CEI) to measure the compactability of the samples. Samples with different filler types and content are used for the analysis. Effect of fillers on the viscosity of the mastic has been studied previously. Viscosity of mastics in return affects the compactability of the mix in general. In this regard this paper tries to study the effect of fillers on the compaction of hot mix asphalt with the help of the superpave gyratory compactor. Moreover, resistance of the asphalt mix samples against rutting is evaluated using the simple performance test. In this test, the sample is subjected to a hydraulic loading while strain transducers attached to the sample measure the displacement. A computer program receives the displacement data at various frequencies and calculates the dynamic modulus and flow number which are used for the evaluation of the pavement performance.     :