The Experts below are selected from a list of 726 Experts worldwide ranked by ideXlab platform
R J Markunas - One of the best experts on this subject based on the ideXlab platform.
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etch delineation of defects in diamond by exposure to an Oxidizing Flame
Journal of Materials Research, 1993Co-Authors: D P Malta, J B Posthill, R A Rudder, G C Hudson, R J MarkunasAbstract:An experimental study of the etching properties of defects in diamond using propane Flame exposure in air is presented. Both natural diamond crystals and polycrystalline diamond films were exposed to a Flame for an optimum time of 3 ‐ 4 s. This process topographically delineates defects in diamond via an accelerated etch rate at defect sites. Using transmission electron microscopy (TEM) to determine the exact nature and density of defects present in the diamond, we have found a direct correlation between topographical delineation observed by scanning electron microscopy (SEM) and the defect structure observed by TEM.
Vargas Galvis Fabio - One of the best experts on this subject based on the ideXlab platform.
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Copper alloy coatings manufactured by oxy-fuel thermal spray onto a porcelain substrate
Medellín Colombia, 2015Co-Authors: Soto Martínez Daniela, Parra Velásquez Carolina, López Gómez, María Esperanza, Vásquez Jiménez, Carlos Federico, Vargas Galvis FabioAbstract:RESUMEN: Se desarrolló un sistema constituido por un sustrato cerámico de porcelana y un recubrimiento de una aleación de cobre, con el fin de proporcionar una superficie conductora de la electricidad en partes específicas del sustrato. Para ello se analizó previamente la mejor manera de preparar la superficie del sustrato para que las partículas de la aleación de cobre se adhieran a él. Para la elaboración del recubrimiento se utilizó un polvo marca Eutectic CastolinTM referencia 21071, el cual fue proyectado utilizando llamas oxiacetilénicas producidas a partir de dos diferentes relaciones volumétricas de combustible-comburente (1:1,15 y 1:2,5), dando como resultado una llama reductora y una oxidante respectivamente. El efecto de la preparación superficial del sustrato, así como el del espesor del recubrimiento y el de la energía de la llama sobre la estructura y adherencia del recubrimiento fue evaluado, encontrando que los recubrimientos obtenidos utilizando una llama reductora tienen baja adherencia al sustrato cerámico preparado superficialmente, y un alto nivel de porosidad en su estructura, mientras que aquellos elaborados utilizando una llama oxidante tienen la mayor adherencia y su estructura es homogénea (baja porosidad). Finalmente, los recubrimientos depositados con los dos tipos de llama sobre sustratos sin preparación superficial presentaron muy baja o nula adherencia.ABSTRACT: A coated system consisting of a ceramic substrate and a coating of a copper alloy was developed in order to provide electrically conductive properties to specific surface of the substrate. The coatings were elaborated by oxy-fuel thermal spraying processes. The best way to prepare the surface of the substrate was previously determined to achieve a sufficient adherence of copper alloy particles on the ceramic substrate. In order to manufacture the coatings an Eutectic CastolinTM 21071 powder was used, the oxy-fuel Flames were produced from two different volumetric acetylene-oxygen ratios (1:1.15 and 1:2.5) obtaining a reducing and Oxidizing Flame respectively. The effect of surface preparation of the substrate, the coating thickness and the energy of the Flame on the structure and coating adhesion were evaluated. It was found that the coatings obtained using a reducing Flame presented lower adhesion values to the ceramic substrate and a higher level of porosity in its structure, while those made using an Oxidizing Flame presented greater adhesion and an homogenous structure (low porosity). Finally, a very low adhesion values were obtained on the non-prepared substrates with both Flames
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Copper alloy coatings manufactured by oxy-fuel thermal spray onto a porcelain substrate
'Instituto Tecnologico Metropolitano (ITM)', 2015Co-Authors: Soto Martínez Daniela, Parra Velásquez Carolina, López-gómez, María E., Vásquez-jiménez, Carlos F., Vargas Galvis FabioAbstract:Se desarrolló un sistema constituido por un sustrato cerámico de porcelana y un recubrimiento de una aleación de cobre, con el fin de proporcionar una superficie conductora de la electricidad en partes específicas del sustrato. Para ello se analizó previamente la mejor manera de preparar la superficie del sustrato para que las partículas de la aleación de cobre se adhieran a él. Para la elaboración del recubrimiento se utilizó un polvo marca Eutectic Castolin referencia 21071TM, el cual fue proyectado utilizando llamas oxiacetilénicas producidas a partir de dos diferentes relaciones volumétricas de combustible-comburente (1:1,15 y 1:2,5), dando como resultado una llama reductora y una oxidante respectivamente. El efecto de la preparación superficial del sustrato, así como el del espesor del recubrimiento y el de la energía de la llama sobre la estructura y adherencia del recubrimiento fue evaluado, encontrando que los recubrimientos obtenidos utilizando una llama reductora tienen baja adherencia al sustrato cerámico preparado superficialmente, y un alto nivel de porosidad en su estructura, mientras que aquellos elaborados utilizando una llama oxidante tienen la mayor adherencia y su estructura es homogénea (baja porosidad). Finalmente, los recubrimientos depositados con los dos tipos de llama sobre sustratos sin preparación superficial presentaron muy baja o nula adherencia.A coated system consisting of a ceramic substrate and a coating of a copper alloy was developed in order to provide electrically conductive properties to specific surface of the substrate. The coatings were elaborated by oxy-fuel thermal spraying processes. The best way to prepare the surface of the substrate was previously determined to achieve a sufficient adherence of copper alloy particles on the ceramic substrate. In order to manufacture the coatings an Eutectic Castolin 21071TM powder was used, the oxy-fuel Flames were produced from two different volumetric acetylene-oxygen ratios (1:1.15 and 1:2.5) obtaining a reducing and Oxidizing Flame respectively. The effect of surface preparation of the substrate, the coating thickness and the energy of the Flame on the structure and coating adhesion we
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Elaboración de recubrimientos base cobre sobre un sustrato de porcelana mediante proyección térmica con llama oxiacetilénica
2015Co-Authors: Soto Martínez Daniela, López-gómez, María E., Vásquez-jiménez, Carlos F., Parra Carolina, Vargas Galvis FabioAbstract:A coated system consisting of a ceramic substrate and a coating of a copper alloy was developed in order to provide electrically conductive properties to specific surface of the substrate. The coatings were elaborated by oxy-fuel thermal spraying processes. The best way to prepare the surface of the substrate was previously determined to achieve a sufficient adherence of copper alloy particles on the ceramic substrate. In order to manufacture the coatings an Eutectic Castolin 21071TM powder was used, the oxy-fuel Flames were produced from two different volumetric acetylene-oxygen ratios (1:1.15 and 1:2.5) obtaining a reducing and Oxidizing Flame respectively. The effect of surface preparation of the substrate, the coating thickness and the energy of the Flame on the structure and coating adhesion werSe desarrolló un sistema constituido por un sustrato cerámico de porcelana y un recubrimiento de una aleación de cobre, con el fin de proporcionar una superficie conductora de la electricidad en partes específicas del sustrato. Para ello se analizó previamente la mejor manera de preparar la superficie del sustrato para que las partículas de la aleación de cobre se adhieran a él. Para la elaboración del recubrimiento se utilizó un polvo marca Eutectic Castolin referencia 21071TM, el cual fue proyectado utilizando llamas oxiacetilénicas producidas a partir de dos diferentes relaciones volumétricas de combustible-comburente (1:1,15 y 1:2,5), dando como resultado una llama reductora y una oxidante respectivamente. El efecto de la preparación superficial del sustrato, así como el del espesor del recubrimiento y el de la energía de la llama sobre la estructura y adherencia del recubrimiento fue evaluado, encontrando que los recubrimientos obtenidos utilizando una llama reductora tienen baja adherencia al sustrato cerámico preparado superficialmente, y un alto nivel de porosidad en su estructura, mientras que aquellos elaborados utilizando una llama oxidante tienen la mayor adherencia y su estructura es homogénea (baja porosidad). Finalmente, los recubrimientos depositados con los dos tipos de llama sobre sustratos sin preparación superficial presentaron muy baja o nula adherencia
D P Malta - One of the best experts on this subject based on the ideXlab platform.
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etch delineation of defects in diamond by exposure to an Oxidizing Flame
Journal of Materials Research, 1993Co-Authors: D P Malta, J B Posthill, R A Rudder, G C Hudson, R J MarkunasAbstract:An experimental study of the etching properties of defects in diamond using propane Flame exposure in air is presented. Both natural diamond crystals and polycrystalline diamond films were exposed to a Flame for an optimum time of 3 ‐ 4 s. This process topographically delineates defects in diamond via an accelerated etch rate at defect sites. Using transmission electron microscopy (TEM) to determine the exact nature and density of defects present in the diamond, we have found a direct correlation between topographical delineation observed by scanning electron microscopy (SEM) and the defect structure observed by TEM.
Wang Xinzhi - One of the best experts on this subject based on the ideXlab platform.
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fire retardant treatment process of plastics
2014Co-Authors: Wang XinzhiAbstract:A fire retardant treatment process of plastics comprises the particular steps of plastic degreasing, plastic swelling, preparation of boiled liquid, plastic aging, Oxidizing Flame treatment, vacuum processing and plastic drying. The fire retardant treatment process of plastics has the advantages of being simple, being low in needed treatment cost, isolating combustion from the inside of the plastics, and obviously improving safety.
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treatment process for improving cleaning antibacterial capacity of plastics
2014Co-Authors: Wang XinzhiAbstract:A treatment process for improving the cleaning antibacterial capacity of plastics comprises the particular steps of plastic degreasing, plastic excitation, plastic coarsening, Oxidizing Flame processing, antibacterial layer spraying, modified coating, hydrophilia treatment and water washing and drying. The treatment process for improving the cleaning antibacterial capacity of plastics is simple and capable of obviously improving the cleaning antibacterial capacity of the surfaces of plastics, and the treated plastics are more beautiful and higher in practicability.
Julian F Tyson - One of the best experts on this subject based on the ideXlab platform.
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determination of lead by hydride generation atom trapping Flame atomic absorption spectrometry
Journal of Analytical Atomic Spectrometry, 2008Co-Authors: Nusret Ertas, Zikri Arslan, Julian F TysonAbstract:An atom trapping approach is described for the determination of lead by hydride generation Flame atomic absorption spectrometry. Lead hydride (PbH4), generated on-line by reacting lead in hydrochloric acid–potassium ferricyanide medium with sodium borohydride (NaBH4), was trapped on the interior walls of a slotted T-tube under highly Oxidizing Flame conditions. Atomization was achieved by aspirating 50 µL of methyl isobutyl ketone (MIBK) to the Flame. Optimization of the experimental parameters for the generation and collection of lead hydride was described to achieve the highest peak height sensitivity. The detection limits were 0.075, 0.047 and 0.028 µg L−1 for 2.6, 5.2 and 7.8 mL of blank solution (n = 13), respectively. Calibration was linear up to 3.0 µg L−1 for a 30-s trapping period. The relative standard deviation was between 2 and 4%. The method was successfully applied to the determination of Pb in NIST certified reference materials, San Joaquin Soil (SRM 2709) and Apple Leaves (SRM 1515).
