Aluminium metal matrix composites are highly dominated composites for various applications such as military, marine, aircraft, aerospace and automobile because of their corrosion resistance, tribological and mechanical properties. In this research, aluminium alloy 5032 composite reinforced with SiCnp (4, 8, 12 and 16 wt.%) was manufactured using stir casting method and subjected to various mechanical, metallurgical and wear tests. The novelty of this research lies in the fabrication and characterization of Al5032/SiCnp composites, which has been not done before. The Energy Dispersive X ray analysis (EDAX) was used to examine the presence of SiC in Al5032 matrix and Scanning Electron Microscope (SEM) was employed to examine the microstructure of the composite. Further micro hardness, wear resistance, tensile and impact tests were carried out. The aforesaid properties increases upto 12 wt.% addition of silicon carbide in Al5032 alloy and thereafter reduces. The nanocomposite Al5032/12wt.%SiC exhibits 98 HV, 256 MPa tensile strength, 19 MPa impact strength and 5 mg wear loss. military marine aircraft resistance 503 4, 4 (4 8 1 wt Al5032SiCnp AlSiCnp Al before EDAX (EDAX Al503 SEM (SEM hardness out wt. reduces Al503212wtSiC AlwtSiC 12wt 9 HV 25 loss 50 ( Al50 wtSiC 2 Al5

ABSTRACT Objective: To evaluate the effectiveness of oil pulling in the management of oral submucous fibrosis (OSMF). Material and Methods: A total of 62 patients clinically and histopathologically diagnosed as OSMF were incorporated in the present study. The subjects are randomly divided equally into two groups, Group A (oil pulling group) and Group B (placebo group). Subjects in Group A were asked to perform OP with sesame oil on an empty stomach in the morning for 3 months and Group B was given placebo capsules for 3 months. Assessment of various clinical parameters was done regularly, and data were analyzed using the Chi-square test. Results: Eighty-two percent had a habit of betel nut chewing, while 18% of the patients had tobacco chewing habits, which were among the main causative factors for OSMF. Clinical improvements in mouth opening, tongue protrusion, difficulty in speech and deglutition, and burning sensation were significant in the Group A. None of the patients reported any discomfort or side effects. The symptoms were not severe in nature and resolved in few days without stopping the therapy. Conclusion: Oil pulling can bring about significant clinical improvements in the symptoms like a mouth opening and tongue protrusion.

Resumo Este artigo apresenta uma abordagem para avaliar a capacidade residual de estruturas de concreto danificadas pelo fogo. A abordagem envolve capturar a resposta em três fases; ou seja, resposta estrutural em condições ambiente (antes da exposição ao fogo), resposta termomecânica durante a exposição ao fogo e resposta residual pós-incêndio após o resfriamento do membro estrutural. A abordagem proposta é implementada em um modelo numérico abrangente desenvolvido no programa computacional ABAQUS de elementos finitos para avaliar especificamente a capacidade residual de uma viga de CA após exposição a diferentes cenários de incêndio. Previsões do modelo numérico são utilizados para destacar a importância de cada fase de análise em avaliar a capacidade residual real de elementos de concreto danificado pelo fogo.

Abstract This paper presents an approach to evaluate residual capacity of fire-damaged concrete structures. The approach involves capturing response in three stages; namely, structural response at ambient conditions (prior to fire exposure), thermo-mechanical response during fire exposure, and post-fire residual response after cooling down of the structural member. The proposed approach is implemented in a comprehensive numerical model developed in the finite element computer program ABAQUS for specifically evaluating residual capacity of an RC beam after exposure to different fire scenarios. Predictions from the numerical model are utilized to highlight importance of each stage of analysis in evaluating realistic residual capacity of fire damaged concrete members.

Resumen Este artículo presenta un enfoque para evaluar la capacidad residual de estructuras de concreto deterioradas por el fuego. El enfoque implica capturar la respuesta entre las fases; es decir, respuesta estructural en condiciones ambiente (antes de la exposición al fuego), respuesta termo mecánica durante la exposición al fuego y respuesta residual incorporación-incendio, luego del enfriamiento del miembro estructural. El enfoque propuesto es implementado en un modelo numérico exhaustivo desarrollado en el programa computacional ABAQUS de elementos finitos para evaluar específicamente la capacidad residual de una viga de CA luego de la exposición a diferentes escenarios de incendio. Previsiones del modelo numérico son utilizadas para destacar la importancia de cada fase del análisis en evaluar la capacidad residual real de elementos de concreto dañados por el fuego.

Present research work analyses the effect of heating modes on the densification, microstructure and mechanical properties of aluminum alloys [65Al-20Cu-15Mn] fabricated through powder metallurgy route. Sintering of compacts using conventional, microwave and spark plasma sintering methods has been carried out at 525°C. From the results, it has been observed that the spark plasma sintering method produced the samples with better mechanical properties than the other two methods, followed by microwave and conventionally sintered counterparts. Microstructural analysis using optical microscopy revealed that spark plasma sintered sample has finest microstructure due to faster rate of heating than microwave and conventional methods.

Neste trabalho, nanocompósitos obtidos a partir de blendas entre o poli (ácido lático) e o terpolímero (etileno/acrilato de metila/metacrilato de glicidila) foram confeccionados. A argila organofílica comercial Cloisite 20A foi utilizada como nanocarga. Interações entre a argila e o terpolímero foram investigadas por reometria de torque. As estruturas dos nanocompósitos foram determinadas por difração de raios X, sendo obtidos nanocompósitos intercalados e microcompósitos. A atuação da argila como agente compatibilizante foi evidenciada por fotomicrografias obtidas por microscopia eletrônica de varredura. As propriedades mecânicas das blendas mostraram-se dependentes tanto da morfologia como do grau de dispersão da argila.

Nanocomposites obtained from blends of poly (lactic acid) and an ethylene/methyl acrylate/glycidyl methacrylate (EMA-GMA) terpolymer were prepared. The commercial organoclay Cloisite 20A was used as nanocharge. Interactions between the clay and the terpolymer were investigated by torque rheometry, while the structure of the nanocomposites was determined by X-ray diffraction. The results revealed the formation of intercalated nanocomposites and microcomposites. The role of clay as a compatibilizing agent was evidenced by SEM micrographs. The mechanical properties proved to be dependent on both the morphology and the degree of dispersion of the clay.

In this work, Polylactide/Biopolyethylene blends were developed. Although some studies have been carried out on polylactide/polyethylene blends, none of them has used polyethylene synthesized with raw material obtained from natural sources. Due to the incompatibility between polylactide and polyethylene, E-GMA and EMA-GMA compatibilizers were used. These compatibilizers present glycidyl methacrylate groups in their structure, which may react with the functional end-groups of polylactide. To evaluate the properties, the blends were characterized by mechanical tests, scanning electron microscopy (SEM) and melt flow index (MFI). The results indicated that the compatibilizers played an important role in the blends, interacting with the blends components, modifying the morphology and improving the mechanical properties.

O poli(ácido lático) é um polímero biodegradável proveniente de fontes renováveis com grande potencial para substituir polímeros não biodegradáveis provenientes do petróleo. Entretanto, seu uso em determinadas aplicações é restringido devido a sua elevada fragilidade e rigidez. Com o intuito de tornar o PLA mais tenaz, o terpolímero (etileno/acrilato de metila/metacrilato de glicidila) -EMA-GMA foi adicionado ao PLA em diferentes concentrações. A adição do EMA-GMA tornou o PLA mais estável durante o processamento. Por FTIR comprovou-se a existência de reação química entre os grupos terminais do PLA e grupos do EMA-GMA. A partir dos ensaios mecânicos observou-se uma resistência ao impacto três vezes superior à do PLA puro.

The Poly(lactic acid) is a biodegradable polymer from renewable sources with potential to replace non-biodegradable polymers derived from petroleum. However its use is restricted in certain applications due to its high brittleness and rigidity. In order to make the PLA more tenacious, the terpolymer (ethylene/methyl acrylate/glycidyl methacrylate) - EMA-GMA was added to PLA in different concentrations. The addition of EMA-GMA to PLA turned the blends more stable during processing. The FTIR data confirmed the chemical reaction between groups in PLA and the EMA-GMA. A three fold increase was observed in the impact strength compared to pure PLA.

Neste trabalho foram desenvolvidos nanocompósitos de polímero/argila a partir de blendas com matriz de PA6. Inicialmente foi avaliado por reometria de torque a reatividade dos copolímeros funcionais PEgAA, PEgMA e EG com a PA6 e a influência destes no sistema PA6/argila. Os ensaios de reometria de torque mostraram que o copolímero PEgAA foi o que apresentou maior reatividade com a PA6. Já nos sistemas de PA6/Argila, o copolímero EG foi o que apresentou a maior interação com o sistema PA6/argila corroborado pelo aumento do torque em função do tempo. Os nanocompósitos foram caracterizados por Difração de Raios-X (DRX), Calorimetria Exploratória Diferencial (DSC), propriedades mecânicas e Microscopia Eletrônica de Varredura (MEV). Os resultados de DRX indicaram que o sistema PA6/CL20A apresentou estrutura intercalada enquanto que os sistemas PA6/EG/CL20A apresentaram estrutura parcialmente esfoliada. Os ensaios de DRX e DSC indicaram que no sistema PA6/EG/CL20A onde a argila foi pré-intercalada na PA6, a mesma ficou localizada na fase de PA6 enquanto que no sistema onde a argila foi pré-intercalada no copolímero EG a mesma ficou localizada na fase de EG. O sistema PA6/EG/CL20A onde a argila foi pré-intercalada na PA6 apresentou propriedades de módulo e resistência ao impacto balanceadas quando comparadas às da PA6. Os ensaios de MEV indicaram que a argila está bem dispersa nos sistemas PA6/CL20A e PA6/EG/CL20A.

In this work polymer/clay nanocomposites from blends with PA6 matrix were developed. Torque rheometry was used to evaluate the reactivity of different copolymers with PA6 and their influence on the PA6/clay system. The nanocomposites were characterized by X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), mechanical properties and Scanning Electron Microscopy (SEM). Torque rheometry analysis showed that the PEgAA copolymer exhibited the highest reactivity with PA6 while the EG copolymer showed better interaction with the PA6/Clay system. XRD results indicated that PA6/CL20A system presented intercalated structure, while PA6/EG/CL20A systems presented a partially exfoliated structure. XRD and DSC analyses indicated that PA6/EG/CL20A system where the clay was pre-intercalated in PA6, the clay was located in the PA6 phase while in the system where the clay was pre-intercalated in the EG copolymer, the clay was located in the EG phase. The PA6/EG/CL20A system where the clay was pre-intercalated into PA6 presented balanced modulus and impact strength properties when compared to PA6. SEM tests showed that the clay is well dispersed in the PA6/CL20A and PA6/EG/CL20A systems.

Neste trabalho investigamos o efeito de diferentes compatibilizantes na reometria de torque, propriedades mecânicas e morfologia das blendas de PA6/PEAD. As blendas foram preparadas em uma extrusora dupla-rosca contra-rotativa com filetes totalmente interpenetrantes, a 240 °C em todas as zonas e velocidade de 50 rpm. A composição das blendas foi de 80/20 (% em peso) para as blendas binárias de PA6/PEAD e de 80/10/10 (% em peso) para as blendas ternárias de PA6/Compatibilizante/PEAD. Os resultados mostraram que houve um aumento no torque das blendas de PA6/PEAD com a adição dos compatibilizantes. O compatibilizante PEgAA foi o que apresentou maior reatividade com a PA6. Entretanto, foi observada uma redução no torque devido à degradação. Os resultados de propriedades mecânicas mostraram que houve aumento considerável na resistência ao impacto das blendas de PA6/PEAD quando os compatibilizantes foram adicionados. Estes resultados foram corroborados pelos dados de deformação na ruptura sob tração. Os resultados de MEV mostraram que a adição dos compatibilizantes às blendas de PA6/PEAD reduziu significativamente o tamanho médio das partículas de PEAD, e melhorou a adesão entre as fases desses polímeros, resultando principalmente, em um aumento da resistência ao impacto.

In this paper, an investigation was made of the effect of different compatibilizers on the torque rheometry, mechanical properties, and morphology of Polyamide 6 (PA6)/High Density Polyethylene (HDPE) blends. The compatibilizers used were PEgAA, PEgMA, and EMA-GMA. The blends were prepared in a counter-rotating intermeshing twin screw extruder, at 240 °C in all zones, and screw speed of 50 rpm. The composition of the blends was 80/20 (wt%) for PA6/HDPE binary blend and 80/10/10 (wt%) for PA6/Compatibilizer/HDPE blends. The blends were characterized by torque rheometry, mechanical properties, and Scanning Electron Microscopy (SEM). Torque rheometry analysis has shown that there was an increase in the torque of PA6/HDPE blend when the compatibilizers were added. PEgAA compatibilizer was more reactive with PA6 than the other compatibilizers. However, the torque decreased due to degradation. There was a substantial increase in impact strength of PA6/HDPE blend when the compatibilizers were added. These results were corroborated by the strain at break data. SEM results indicated that the addition of compatibilizers to PA6/PE blend has considerably decreased the HDPE average particles size and improved the adhesion between PA6 and HDPE phases, resulting in an increase in impact strength.

Commercialization of large-area electrochromic glazing is reviewed with respect to device configuration and materials employed. Device configurations including electrochromic solutions and solid state electrochromic layers are discussed as well as novel user-controlled photochromic and gasochromic devices.