A review study on coupling agents used as ceramic fillers modifiers for dental applications

Author(s):  
Ban Ali Sabri ◽  
S. Meenaloshini ◽  
N.M. Abreeza ◽  
Abdulrahman N. Abed
2012 ◽  
Vol 2 (5) ◽  
pp. 204-205
Author(s):  
Nimesh A Patel ◽  
◽  
Pradip M Patel ◽  
Prof. A. B. Patel Prof. A. B. Patel

Author(s):  
Mwinyikione Mwinyihija

The review study closely introspects’ on the prerequisites of evidence-based curriculum within the realms of specialized skills development agenda as pursued through higher education Institutions in Africa. Explicitly, the constraining factors that bedevil the leather sector are identifiable when appropriate research designs tools are applied. As such, in the process of identifying the constraints, renascence themes could, therefore, be beneficial in collecting evidence in support of developing curriculum. Such a developed curriculum stands higher chances of acceptability and aptly mitigates against challenges related to specialized skills development. The review succinctly indicates that in the process of identifying the themes, the scope of collecting evidence becomes attainable, thus, improving curricula that entails a participatory and transformative orientation. Indeed, during the review phase of the study, three main perspectives are depicted to be consequential in attaining a comprehensive, evidence-based curriculum, such as; action research, backward curriculum design perspective and theoretical perspective. Therefore, about this perspective, a reflection based on personal experiences and related to new knowledge with what they already know leads to constructivism. The relevancy of a constructivist strategy is observed to facilitate the observatory and evaluative stance during the development of evidence-based curriculum. Moreover, in consolidating and sustaining the benefit of such a developed curriculum, threshold concept was found during the review that it complements the process and strengthens the collecting evidence for curriculum development. Accordingly, therefore, the result of the review study indicate that Africa would  position itself for initiating transformational changes in aspects of specialized higher education, fruition towards socio-economic benefits (e.g. employment, wealth creation and technology transfer), reversal of urban-rural or inter/intra continental migration flurry.


2010 ◽  
Vol 38 (1) ◽  
pp. 80-98 ◽  
Author(s):  
M. Gerster ◽  
C. Fagouri ◽  
E. Peregi

Abstract One challenge facing green tire technology is to achieve good silica hydrophobation/dispersion within the polymer matrix without a detrimental increase in the rubber compound’s viscosity during compounding. This phenomenon is well known to be induced by premature and unwanted coupling and/or crosslinking of the traditional coupling agents. The current state-of-the-art polysulfides silanes, bis(3-triethoxysilylpropyl)tetrasulfide and to a lesser extent bis(3-triethoxysilylpropyl)disulfide (“Product Application—VP Si 75/VP X 75-S in the Rubber Industry,” Degussa Hüls Report No. PA 723.1E), need to be carefully incorporated with careful temperature control during the rubber compounding to prevent this “scorchy” behavior. This paper will present novel monofunctional silanes which are suited for preparing highly silica-loaded rubber compounds of superior processability, while applying fewer mixing passes, thereby reducing mixing times which can lead to improved productivity and cost savings. Additionally, these safer coupling agents can be processed at higher temperatures which can, again, lead to reduced mixing time and better ethanol removal thereby improving the tire’s physical properties and reducing the volatile organic compounds generated during the tire’s use. The rubber compounds produced using these monofunctional silanes are characterized by lower Mooney viscosity and improved processability. Advantageously, within these novel chemical classes of coupling agents, selective functionalization of the silanes allows production of tailor-made coupling agents which can respond to the specific requirements of the tire industry (Vilgis, T. A. and Heinrich, G., “Die Physic des Autoreifens,” Physikalische Blätter, Vol. 57, 2001, pp. 1–7).


2020 ◽  
Vol 10 (31) ◽  
pp. 96-104
Author(s):  
Caroline Muller Almeida ◽  
Suelen Elias da Veiga Freitas ◽  
Aline Affonso Luna ◽  
Cintia Silva Fassarella ◽  
Priscilla Alfradique de Souza

Identificar e analisar evidências científicas adotadas na prevenção de recidivas de úlceras venosas. Trata-se de um estudo de revisão integrativa da literatura, descritivo, de abordagem qualitativa, realizado entre outubro e novembro de 2017, a partir de consulta de bases de dados nacionais e internacionais. Os descritores utilizados foram “úlcera venosa”, “úlcera varicosa”, “recidiva” associados à palavra chave “prevenção”. Recorreu análise temática de conteúdo, emergindo duas categorias. Dos 305 artigos encontrados, 10 foram selecionados atendendo aos critérios de seleção. As principais evidências observadas foram “medidas para a prevenção de recidivas de úlceras venosas” e “facilidades e dificuldades da implementação de medidas preventivas”. Evidenciou-se que as medidas são diversas para prevenir as recidivas de úlcera venosa, no entanto, a adesão ainda é fator limitador as práticas devido à complexidade que a envolve.Descritores: Úlcera Venosa, Recidiva, Prevenção. Measures to prevent recurrence of venous ulcersAbstract: To identify and analyze scientific evidences adopted in the prevention of venous ulcers recurrences. It is an integrative literature review study, descriptive, with a qualitative approach, carried out between October and November 2017, based on consultation of national and international databases. The descriptors used were "venous ulcer", "varicose ulcer", "relapse" associated with the key word "prevention". It resorted to thematic analysis of content, emerging two categories. Of the 305 articles found, 10 were selected according to the selection criteria. The main evidences observed were "measures for the prevention of relapses of venous ulcers" and "facilities and difficulties of the implementation of preventive measures". It was evidenced that the measures are diverse to prevent the recurrence of venous ulcer, however, adherence is still a limiting factor to the practices due to the complexity that involves it.Descriptors: Venous Ulcer, Relapse, Prevention. Medidas para la prevención de recidivas de úlceras venosasResumen: Identificar y analizar evidencias científicas adoptadas en la prevención de recidivas de úlceras venosas. Este es un estudio integrador de revisión de literatura, descriptivo, con un enfoque cualitativo, realizado entre octubre y noviembre de 2017, basado en la consulta de bases de datos nacionales e internacionales. Los descriptores utilizados fueron "úlcera venosa", "úlcera varicosa", "recidiva" asociados a la palabra clave "prevención". Se recurrió análisis temático de contenido, emergiendo dos categorías. De los 305 artículos encontrados, 10 fueron seleccionados atendiendo a los criterios de selección. Las principales evidencias observadas fueron "medidas para la prevención de recidivas de úlceras venosas" y "facilidades y dificultades de la aplicación de medidas preventivas". Se evidenció que las medidas son diversas para prevenir las recidivas de úlcera venosa, sin embargo, la adherencia todavía es factor limitante en las prácticas debido a la complejidad que la envuelve.Descriptores: Úlcera Varicosa, Recurrencia, Prevención.


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