Documents disponibles écrits par cet auteur

Reduction of chemical reaction mechanism for halide-assisted silicon carbide epitaxial film deposition / Rong Wang in Industrial & engineering chemistry research, Vol. 48 N° 8 (Avril 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 8 (Avril 2009) . - pp. 3860–3866 Titre : Reduction of chemical reaction mechanism for halide-assisted silicon carbide epitaxial film deposition Type de document : texte imprimé Auteurs : Rong Wang, Auteur ; Ronghui Ma, Auteur ; Michael Dudley, Auteur Année de publication : 2009 Article en page(s) : pp. 3860–3866 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Gas-phase  composition  Halide-assisted  chemical  vapor  deposition  Silicon  carbide  film  growth  Three-dimensional  simulation Résumé : Simulation of gas-phase and surface chemistry is an essential part in numerical study of chemical vapor deposition for film growth. When integrated with a model for transport processes such as gas flow, heat transfer, and mass transfer, it allows the prediction of gas-phase composition, film deposition rate, and film uniformity. For halide-assisted chemical vapor deposition of silicon carbide film growth, three-dimensional simulation of the deposition process can be time-consuming due to the large number of chemical reactions involved. In this study, a simplified chemical reaction mechanism was developed for silicon carbide growth with silicon tetrachloride and propane as precursors. After model validation, the reduced reaction steps were implemented into a three-dimensional simulation of halide-assisted chemical vapor deposition to predict the distributions of gas velocity, temperature, concentration of the intermediate reactants, and film deposition rate. Specifically, the effects of deposition pressure on the film growth were investigated. The integrated model for chemistry and transport process demonstrated the capability of modeling a deposition process with reasonable computing time. We envision that this model will provide a useful tool for design, test, and optimization of the deposition process for growing silicon carbide films or bulk crystals by use of halide-assisted chemical vapor deposition process. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8017093 [article] Reduction of chemical reaction mechanism for halide-assisted silicon carbide epitaxial film deposition [texte imprimé] / Rong Wang, Auteur ; Ronghui Ma, Auteur ; Michael Dudley, Auteur . - 2009 . - pp. 3860–3866. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 8 (Avril 2009) . - pp. 3860–3866 Mots-clés : Gas-phase  composition  Halide-assisted  chemical  vapor  deposition  Silicon  carbide  film  growth  Three-dimensional  simulation Résumé : Simulation of gas-phase and surface chemistry is an essential part in numerical study of chemical vapor deposition for film growth. When integrated with a model for transport processes such as gas flow, heat transfer, and mass transfer, it allows the prediction of gas-phase composition, film deposition rate, and film uniformity. For halide-assisted chemical vapor deposition of silicon carbide film growth, three-dimensional simulation of the deposition process can be time-consuming due to the large number of chemical reactions involved. In this study, a simplified chemical reaction mechanism was developed for silicon carbide growth with silicon tetrachloride and propane as precursors. After model validation, the reduced reaction steps were implemented into a three-dimensional simulation of halide-assisted chemical vapor deposition to predict the distributions of gas velocity, temperature, concentration of the intermediate reactants, and film deposition rate. Specifically, the effects of deposition pressure on the film growth were investigated. The integrated model for chemistry and transport process demonstrated the capability of modeling a deposition process with reasonable computing time. We envision that this model will provide a useful tool for design, test, and optimization of the deposition process for growing silicon carbide films or bulk crystals by use of halide-assisted chemical vapor deposition process. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8017093

Using microCT imaging technique to quantify heat generation distribution induced by magnetic nanoparticles for cancer treatments / Anilchandra Attaluri in Journal of heat transfer, Vol. 133 N° 1(N° Spécial) (Janvier 2011) 

Public ISBD [article]  in Journal of heat transfer > Vol. 133 N° 1(N° Spécial) (Janvier 2011) . - pp. [011003/1-5] Titre : Using microCT imaging technique to quantify heat generation distribution induced by magnetic nanoparticles for cancer treatments Type de document : texte imprimé Auteurs : Anilchandra Attaluri, Auteur ; Ronghui Ma, Auteur ; Liang Zhu, Auteur Année de publication : 2011 Article en page(s) : pp. [011003/1-5] Note générale : Physique Langues : Anglais (eng) Mots-clés : Magnetic  nanoparticles  Hyperthermia  Cancer  Heating  Temperature  MicroCT  imaging Index. décimale : 536 Chaleur. Thermodynamique Résumé : Magnetic nanoparticles have been used in clinical and animal studies to generate localized heating for tumor treatments when the particles are subject to an external alternating magnetic field. Currently, since most tissue is opaque, the detailed information of the nanoparticle spreading in the tissue after injections cannot be visualized directly and is often quantified by indirect methods, such as temperature measurements, to inversely determine the particle distribution. In this study, we use a high resolution microcomputed tomography (microCT) imaging system to investigate nanoparticle concentration distribution in a tissue-equivalent agarose gel. The local density variations induced by the nanoparticles in the vicinity of the injection site can be detected and analyzed by the microCT system. Heating experiments are performed to measure the initial temperature rise rate to determine the nanoparticle-induced volumetric heat generation rates (or specific absorption rate (SAR W/m3)) at various gel locations. A linear relationship between the measured SARs and their corresponding microCT pixel index numbers is established. The results suggest that the microCT pixel index number can be used to represent the nanoparticle concentration in the media since the SAR is proportional to the local nanoparticle concentration. Experiments are also performed to study how the injection amount, gel concentration, and nanoparticle concentration in the nanofluid affect the nanoparticle spreading in the gel. The nanoparticle transport pattern in gels suggests that convection and diffusion are important mechanisms in particle transport in the gel. Although the particle spreading patterns in the gel may not be directly applied to real tissue, we believe that the current study lays the foundation to use microCT imaging systems to quantitatively study nanoparticle distribution in opaque tumor. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] [article] Using microCT imaging technique to quantify heat generation distribution induced by magnetic nanoparticles for cancer treatments [texte imprimé] / Anilchandra Attaluri, Auteur ; Ronghui Ma, Auteur ; Liang Zhu, Auteur . - 2011 . - pp. [011003/1-5]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 133 N° 1(N° Spécial) (Janvier 2011) . - pp. [011003/1-5] Mots-clés : Magnetic  nanoparticles  Hyperthermia  Cancer  Heating  Temperature  MicroCT  imaging Index. décimale : 536 Chaleur. Thermodynamique Résumé : Magnetic nanoparticles have been used in clinical and animal studies to generate localized heating for tumor treatments when the particles are subject to an external alternating magnetic field. Currently, since most tissue is opaque, the detailed information of the nanoparticle spreading in the tissue after injections cannot be visualized directly and is often quantified by indirect methods, such as temperature measurements, to inversely determine the particle distribution. In this study, we use a high resolution microcomputed tomography (microCT) imaging system to investigate nanoparticle concentration distribution in a tissue-equivalent agarose gel. The local density variations induced by the nanoparticles in the vicinity of the injection site can be detected and analyzed by the microCT system. Heating experiments are performed to measure the initial temperature rise rate to determine the nanoparticle-induced volumetric heat generation rates (or specific absorption rate (SAR W/m3)) at various gel locations. A linear relationship between the measured SARs and their corresponding microCT pixel index numbers is established. The results suggest that the microCT pixel index number can be used to represent the nanoparticle concentration in the media since the SAR is proportional to the local nanoparticle concentration. Experiments are also performed to study how the injection amount, gel concentration, and nanoparticle concentration in the nanofluid affect the nanoparticle spreading in the gel. The nanoparticle transport pattern in gels suggests that convection and diffusion are important mechanisms in particle transport in the gel. Although the particle spreading patterns in the gel may not be directly applied to real tissue, we believe that the current study lays the foundation to use microCT imaging systems to quantitatively study nanoparticle distribution in opaque tumor. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...]