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RéPLICAS óSEAS EN RESINA POLIESTER COMO HERRAMIENTA DIDáCTICA PARA EL APRENDIZAJE DE ANATOMíA POLYESTER RESIN BONE REPLICA, AS DIDACTIC TOOL FOR ANATOMY LEARNING  [cached]
Yobany Quijano Blanco,Freddy Camilo Rodríguez M.,Karen Peralta R.,Sebastián Cortés C.
Revista U.D.C.A Actualidad & Divulgación Científica , 2012,
Abstract: Las técnicas utilizadas para la reproducción de piezas óseas humanas con fines académicos intentan hallar métodos que permitan obtener replicas óseas exactas de buena calidad, conservando, dentro de lo posible, los elementos anatómicos y accidentes óseos, en tres dimensiones, lo cual, no es tan fácil de obtener con las técnicas existentes. Mediante el procedimiento que se utilizó en este estudio para su realización obtuvimos, como primera medida, moldes y copias exactas de los huesos de los miembros inferiores, superiores y del cráneo; de estos últimos, algunos desarticulados, para facilitar su manejo. El material empleado en esta técnica para obtener réplicas óseas exactas fue la resina de poliéster, mejorando, desde el punto de vista pedagógico, las estrategias didácticas y de aprendizaje, para los estudiantes de anatomía. En el proceso, se dispusieron, como moldes, huesos reales de todos las dimensiones, fibra de vidrio, carbonato de calcio, resina poliéster, esta última, como componente principal de la réplica, logrando una copia fiel de cada uno de los huesos humanos utilizados, encontrando una adecuada fidelidad, en cuanto a cada uno de los accidentes anatómicos óseos, lo cual, permite prevenir complicaciones, que se pueden presentar durante la manipulación y la adquisición de huesos reales, ante los organismos de salud y cementerios De esta manera, se halló otra alternativa para el manejo externo de huesos humanos, con fines de docencia e investigación, en las diferentes facultades de medicina. The techniques used to reproduce human bone pieces for academic uses are looking for methods which permit to obtain exact replicas of good quality preserving as far as possible the anatomical elements and bone accidents in three dimensions, which is not so easy to get with the existing techniques. With the method used in this study, as a first step molds and exact copies of the leg bones, upper limbs and the disarticulated skull bones (disarticulated for ease of handling) were obtained. The material used in this technique to obtain exact bone replicas was polyester resin, tended to improve from the pedagogical point of view, the teaching and learning strategies for anatomy students. In the process real bones as templates for all actual dimensions, glass fiber, calcium carbonate, polyester resin were used, the latter as a main component of our replica, obtaining a faithful copy of each of the mentioned human bones, finding a suitable fidelity to each anatomical bone accident, which can prevent complications that may occur during handling and acquisition of
Utiliza??o de resina poliester como meio de inclus?o para animais
Jurberg, Pedro;
Revista Brasileira de Zoologia , 1988, DOI: 10.1590/S0101-81751988000400008
Abstract: in this paper the application of the resin poliester (polylite 8001) for the inclusion of animals is described.
SINTESIS XILITOL POLIESTER MENGGUNAKAN DESTILAT ASAM LEMAK MINYAK SAWIT [Synthesis of Xylitol-Polyester from Palm Fatty Acid Distillate(PFAD)]
Suhardi 1),Tranggono 1),Amanda Hardiyani SN 2)
Jurnal Teknologi dan Industri Pangan , 2003,
Abstract: This study of xylitol-polyester synthesis was carried out using palm fatty acid distillate as the a source fatty acids. The objective of this study was to obtain the optimum condition with regard to reaction kinetis during synthesis. In the experiment, temperatures were varied at 110, 120, 130, 140 and 150oC; while during reactions samples were drawn at 0, 3, 6, 9 and 12 hours for determination of hydroxil value. Results showed that the optimum condition for synthesis was found at 145 2.5oC for 3.5 0.5 hours. It was noted, that the reaction was reversible, first order with the activation energy 4475.57 cal/mol for synthesis and 4499.21 cal/mol for hydrolisis.
Experiencia en Plastinación con Resina Poliéster P-4 para Cortes Anatómicos Plastination Experience in Polyester Resin (P-4)
Marcos Valenzuela O,Camila Azocar S,Krystel Werner F,Eduardo Vega P
International Journal of Morphology , 2012,
Abstract: El Laboratorio de Plastinación de la Universidad de los Andes ha trabajado hasta hoy, exclusivamente la técnica en Silicona para preservar el material cadavérico mediante este tipo de conservación. Sin embargo, este método tiene algunas desventajas en cortes anatómicos finos. Se desarrolló un método de plastinación en resina poliéster, en base a la técnica ya protocolizada, adaptándolas a nuestro laboratorio, con el fin de obtener muestras con mayor resistencia y calidad, sin alterar las estructuras. Se utilizaron cortes anatómicos de segmentos distales de miembro inferior humano fijados en acetona a - 17 C y otros de encéfalo de vacuno fijados con formalina acuosa al 10% a 4 C, de un grosor que varía entre 0,4 y 0,8 cm. Se procedió a deshidratar las muestras en acetona a -17 C para luego seleccionar piezas que fueron impregnadas y plastinadas con resina P-4 sin catalizador y otras con catalizador en proporciones 2:1. El proceso de polimerización fue común para ambas con luz ultravioleta. Se obtienen muestras sólidas y rígidas, con cierta transparencia, especialmente en los cortes más finos. No se observaron alteraciones de forma y tama o. Los mejores resultados en cuanto a transparencia, se obtuvieron con la Resina sin catalizador. Se logró estandarizar una técnica con Resina poliéster P-4, obteniendo cortes anatómicos de buena calidad y con una resistencia mucho mayor que la obtenida para este tipo de muestras en la plastinación con Silicona. The plastination laboratory at Universidad de los Andes has always worked exclusively silicone as a technique to preserve cadaveric material. However, this method has disadvantages in thin anatomical pieces. A plastination method has been developed using polyester resin P-4, using an already protocolized technique and adapting it to our laboratory to obtain better quality and resistant pieces, without altering the anatomical structures. Anatomical pieces of human lower extremities were used, which were fixated in acetone at -17 C and bovine encephalous pieces, fixated with 10% aquoeus formalyn at 4 C, with a variable width of 0.4 to 0.8 cm. The pieces were then dehydrated in acetone at -17 C; among these pieces, some were selected, impregnated and plastinated with P-4 resin, using in some of them a catalyst in a ratio of 2:1. The polymerization process was the same for all pieces with ultraviolet light. Solid and rigid pieces were obtained, with a partial transparency, especially on the thinnest cuts. No alterations in size and shape were observed. The best results in transparency were obtained with the technique
Polyester Dendrimers  [PDF]
Jean–d’Amour K. Twibanire,T. Bruce Grindley
Polymers , 2012, DOI: 10.3390/polym4010794
Abstract: Polyester dendrimers have been comprehensively reviewed starting from their first synthesis in the early 1990s by Hawker and Fréchet. Polyester dendrimers have attracted and continue to attract extensive interest because they are comparatively easy to make and because, whenever they have been tested, they have been found to be non-toxic. A number of different strategies for their synthesis have been examined and the methods employed for formation of the ester bond during dendrimer assembly have been summarized. The newest approaches, including the use of bifunctional orthogonally reacting dendrons and accelerated synthesis have been surveyed.
Pengaruh Perlakuan Alkali terhadap Sifat Tarik Bahan Komposit Serat Rami-Polyester
Kuncoro Diharjo
Jurnal Teknik Mesin , 2006,
Abstract: The Natural Composite (NACO) is material that has a good potential to be developed in Indonesia. The mechanical bonding of the composite reinforced natural fiber can be increased by using chemical treatment of fiber or by using the addition of coupling agent. The chemical treatment, for example alkali treatment, is often used because it is more economic. The objective of this research is to investigate the effect of alkali treatment to the tensile properties of unidirectional continuous ramie fiber reinforced polyester composite. Visual inspections were performed to asses the mechanism of fracture. The ramie fiber was immersed in the alkali solution (5% NaOH for 0, 2, 4, and 6 hours. And then, it was washed using fresh water and dried naturally. The matrix used in this research is unsaturated polyester resin 157 BQTN with MEKPO hardener 1% (v/v). The composites were made by using press mold method for Vf " 35%. All specimens were post cured at 62 0C for 4 hours. The tensile test specimens were produced according to ASTM D-638. The tensile test was carried out on a tensile testing machine and the elongation was measured using an extensometer. The fracture surface was investigated to identify the mechanism of fracture. The result shows that the tensile strength and strain of the composites have the optimum values for 2 hours treated fiber, i.e. 190.27MPa, and 0.44% respectively. The longer time of the alkali treatment of fiber increases its modulus. The composite prepared by 6 hours treated fiber has the lowest strength. The fracture surfaces of the composites prepared by 0, 2, and 4 hours alkali treated type are classified as splitting in multiple area. In contrast, the fracture of the composite prepared by 6 hours treated fiber has sigle fracture type. The fracture surface of the composite reinforced untreated fiber shows fiber pull out. in Bahasa Indonesia : Komposit alam (NACO) adalah material yang memiliki potensi yang baik untuk dikembangkan di Indonesia. Mechanical bonding komposit yang diperkuat serat alam dapat ditingkatkan dengan perlakuan kimia serat atau mengunakan coupling agent. Perlakuan kimia, seperti perlakuan alkali, sering digunakan karena lebih ekonomis. Tujuan penelitian ini adalah menyelidiki pengaruh perlakuan alkali terhadap sifat tarik komposit berpenguat serat rami kontinyu dengan matrik poliester. Pengamatan visual dilakukan untuk menyelidiki mekanisme perpatahan. Serat rami direndam di dalam larutan alkali (5% NaOH) selama 0, 2, 4, dan 6 jam. Selanjutnya, serat tersebut dicuci menggunakan air bersih dan dikeringkan secara alami.
Effect of the synthesis method and praseodymium on the electrical properties of Mg-Cubic Zirconia  [cached]
Badenes, J.,Forés, A.,Vicente, M.,Llusar, M.
Boletín de la Sociedad Espa?ola de Cerámica y Vidrio , 1999,
Abstract: The synthesis of nanostructured Mg-FSZ fully stabized zirconia by chemical methods such as colloidal gel, polyester resin and hydrolisis of alkoxides has been studied. The addition of praseodymium ion facilitates cubic stabilization avoiding the Mg- FSZ partitioning with temperature. Praseodymium improve the ionic conductivity of the material probably by the entrance of Pr3+ on the host lattice substitting Zr4+ and subsequently introduction of additional oxygen vacancies trapped near the zirconium ion. En este trabajo se estudia la obtención de circona cúbica estabilizada con magnesio nanoestructurada por métodos químicos tales como el gel coloidal, resina poliester de citrato así como hidrólisis de alcóxidos. La adición de praseodimio mejora la reactividad del sistema y evita la transformación a monoclínica con la temperatura. Asimismo el praseodimio mejora la conductividad iónica del material por un mecanismo de disolución sólida de modo que el Pr3+ introduce nuevas vacantes de oxígeno que podrían quedar asociadas a iones circonio en la red.
Development of Polyester/Eggshell Particulate Composites
S.B. Hassan,V.S. Aigbodion,S.N. Patrick
Tribology in Industry , 2012,
Abstract: The development of Polyester/Eggshell particulate composites has been carried out. Uncarbonized and carbonized eggshell particles were used as reinforcement in polyester matrix. 10 to 50 wt% eggshell particles at intervals of 10 wt% were added to polyester as reinforcement. The microstructural analyses of the polyester/eggshell particulate composites were carried out using SEM and EDS. The mechanical properties and density were carried out by standard methods. The results showed that the density and hardness values of the polyester/eggshell particulate composite increased steadily with increasing eggshell addition. The tensile strength increased from 15.182 N/mm2 at 0 wt% eggshell addition to a maximum of 23.4 N/mm2 at 40 wt% eggshell addition for uncarbonized eggshell; while it increased to a maximum of 28.378 N/mm2 at 20 wt% eggshell addition for carbonized eggshell. Compressive strength increased steadily from 90.3 N/mm2 at 0 wt% eggshell additions to a maximum of 103.6 at 50 wt% eggshell addition for uncarbonized eggshell and 116.5N/mm2 at 50 % eggshell addition for carbonized eggshell. Hardness value increased from 91 HRF at 0 % eggshell addition to a maximum of 120.05HRF at 50 wt% eggshell addition for uncarbonized eggshell and 149.45HRF at 50 wt% eggshell for the carbonized eggshell. Flexural strength increased from 76.06 N/mm2 at 0 wt% eggshell addition to a maximum of 97.06 N/mm2 at 40 wt% eggshell addition for uncarbonized eggshell; however, it increased to a maximum of 106.66 N/mm2 at 20 wt% eggshell addition for the carbonized eggshell. The impact energy also increased from 0.1 Joules at 0 wt% eggshell addition to a maximum of 0.35 Joules at 30 wt% eggshell addition for uncarbonized eggshell; it however increased to a maximum of 0.45 Joules at 20 wt% eggshell addition for the carbonized eggshell. Hence the development of polyester/eggshell particulate composites material with good mechanical properties and light weight which is relevant to the electronics, auto and building industries has been achieved.
Effect of unsaturated polyester concentration on rheological characteristics of polypropylene-unsaturated polyester reactive blend  [PDF]
G. M. Mamoor,Muhammad Naveed Khan,A. Ali,S. Shahid
Chemical Engineering Research Bulletin , 2010,
Abstract: Reactive blends of polypropylene and unsaturated polyester with different compositions were prepared by melt processing using dicumyl peroxide (DCP) as initiator in a plasticoder. Rheological Characteristics of the blends were studied as a function of unsaturated polyester concentration over a range of strain rate. The possibility of forming a graft polymer increased with increasing the unsaturated polyester content. Change in viscosity behavior of the blends was a result of the competing reactions of degradation and grafting.
Microwave Assisted Dyeing of Polyester Fabrics with Disperse Dyes  [PDF]
Saleh Mohammed Al-Mousawi,Morsy Ahmed El-Apasery,Mohamed Hilmy Elnagdi
Molecules , 2013, DOI: 10.3390/molecules180911033
Abstract: Dyeing of polyester fabrics with thienobenzochromene disperse dyes under conventional and microwave heating conditions was studied in order to determine whether microwave heating could be used to enhance the dyeability of polyester fabrics. Fastness properties of the dyed samples were measured. All samples dyed with or without microwave heating displayed excellent washing and perspiration fastness. The biological activities of the synthesized dyes against Gram positive bacteria, Gram negative bacteria, yeast and fungus were also evaluated.
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