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Adsorptive removal of fluoride by micro-nanohierarchal web of activated carbon fibers / Amit Kumar Gupta in Industrial & engineering chemistry research, Vol. 48 N° 21 (Novembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 21 (Novembre 2009) . - pp. 9697–9707 Titre : Adsorptive removal of fluoride by micro-nanohierarchal web of activated carbon fibers Type de document : texte imprimé Auteurs : Amit Kumar Gupta, Auteur ; Dinesh Deva, Auteur ; Ashutosh Sharma, Auteur Année de publication : 2010 Article en page(s) : pp. 9697–9707 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Activated  carbon  fibers  Aluminum  impregnated  hierarchal  web  Chemical  vapor  deposition Résumé : This study describes the development of aluminum impregnated hierarchal web of carbon fibers for the removal of dissolved fluoride in water. Micrometer-sized activated carbon fibers (ACF) were used as a substrate to grow carbon nanofibers (CNF) by chemical vapor deposition (CVD) using Ni as a catalyst. The hierarchal web of micro-nanocarbon fibers (ACF/CNF) thus prepared was impregnated with aluminum (in its metallic state) and then tested for the adsorption of fluoride ions over the concentration range of 1−50 ppm in water under both batch and flow conditions. The adsorbent web showed significant adsorption of fluoride ions. In addition, the total fluoride uptake was observed to be larger on aluminum impregnated ACF/CNF web than on its parent material, the ACF alone impregnated with Al. Various analytical techniques including the scanning electron microscopy (SEM), Raman spectroscopy, and the elemental analyzer were employed to characterize the Al-impregnated ACF/CNF. The SEM images showed a complex 3D network of nanofibers uniformly deposited with Al. This study is a step in developing a general platform suitable for producing potable water that also specifically addresses the problem of fluoride removal. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801688k [article] Adsorptive removal of fluoride by micro-nanohierarchal web of activated carbon fibers [texte imprimé] / Amit Kumar Gupta, Auteur ; Dinesh Deva, Auteur ; Ashutosh Sharma, Auteur . - 2010 . - pp. 9697–9707. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 21 (Novembre 2009) . - pp. 9697–9707 Mots-clés : Activated  carbon  fibers  Aluminum  impregnated  hierarchal  web  Chemical  vapor  deposition Résumé : This study describes the development of aluminum impregnated hierarchal web of carbon fibers for the removal of dissolved fluoride in water. Micrometer-sized activated carbon fibers (ACF) were used as a substrate to grow carbon nanofibers (CNF) by chemical vapor deposition (CVD) using Ni as a catalyst. The hierarchal web of micro-nanocarbon fibers (ACF/CNF) thus prepared was impregnated with aluminum (in its metallic state) and then tested for the adsorption of fluoride ions over the concentration range of 1−50 ppm in water under both batch and flow conditions. The adsorbent web showed significant adsorption of fluoride ions. In addition, the total fluoride uptake was observed to be larger on aluminum impregnated ACF/CNF web than on its parent material, the ACF alone impregnated with Al. Various analytical techniques including the scanning electron microscopy (SEM), Raman spectroscopy, and the elemental analyzer were employed to characterize the Al-impregnated ACF/CNF. The SEM images showed a complex 3D network of nanofibers uniformly deposited with Al. This study is a step in developing a general platform suitable for producing potable water that also specifically addresses the problem of fluoride removal. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801688k

Controlling the morphology of resorcinol−formaldehyde-based carbon xerogels by sol concentration, shearing, and surfactants / Chandra S. Sharma in Industrial & engineering chemistry research, Vol. 48 N° 17 (Septembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 17 (Septembre 2009) . - pp. 8030–8036 Titre : Controlling the morphology of resorcinol−formaldehyde-based carbon xerogels by sol concentration, shearing, and surfactants Type de document : texte imprimé Auteurs : Chandra S. Sharma, Auteur ; Devendra K. Upadhyay, Auteur ; Ashutosh Sharma, Auteur Année de publication : 2009 Article en page(s) : pp. 8030–8036 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Carbon  xerogel  microspheres  Formaldehyde  Nonionic  surfactants  Dilution  ratio  Hydrophilic−lipophilic  balance Résumé : Carbon xerogel microspheres were synthesized by inverse emulsion polymerization of resorcinol with formaldehyde, followed by pyrolysis at 900 °C under nitrogen atmosphere. We have studied the effect of various synthesis parameters, including dilution ratio and hydrophilic−lipophilic balance (HLB) of nonionic surfactants, on the size and morphology of resulting structures. The average particle size of carbon microspheres could be modulated from 1 to 28 μm by varying the dilution ratio over 3 orders of magnitude. Increase in the HLB value and the amount of surfactants produced a variety of dense carbon, but open-architecture fractal-like structures. Three different methods of stirring, namely, magnetic, mechanical, and ultrasonication were applied during the inverse emulsification to produce carbon xerogel microstructures. Formation of a wide spectrum of nonporous carbon particle morphologies, including the highly branched, hierarchical microparticles, by tuning the synthesis conditions may have potential applications in printing technology, controlled drug delivery, biosensors, and carbon-based microelectromechanical systems (C-MEMS) including bio-MEMS. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900359w [article] Controlling the morphology of resorcinol−formaldehyde-based carbon xerogels by sol concentration, shearing, and surfactants [texte imprimé] / Chandra S. Sharma, Auteur ; Devendra K. Upadhyay, Auteur ; Ashutosh Sharma, Auteur . - 2009 . - pp. 8030–8036. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 17 (Septembre 2009) . - pp. 8030–8036 Mots-clés : Carbon  xerogel  microspheres  Formaldehyde  Nonionic  surfactants  Dilution  ratio  Hydrophilic−lipophilic  balance Résumé : Carbon xerogel microspheres were synthesized by inverse emulsion polymerization of resorcinol with formaldehyde, followed by pyrolysis at 900 °C under nitrogen atmosphere. We have studied the effect of various synthesis parameters, including dilution ratio and hydrophilic−lipophilic balance (HLB) of nonionic surfactants, on the size and morphology of resulting structures. The average particle size of carbon microspheres could be modulated from 1 to 28 μm by varying the dilution ratio over 3 orders of magnitude. Increase in the HLB value and the amount of surfactants produced a variety of dense carbon, but open-architecture fractal-like structures. Three different methods of stirring, namely, magnetic, mechanical, and ultrasonication were applied during the inverse emulsification to produce carbon xerogel microstructures. Formation of a wide spectrum of nonporous carbon particle morphologies, including the highly branched, hierarchical microparticles, by tuning the synthesis conditions may have potential applications in printing technology, controlled drug delivery, biosensors, and carbon-based microelectromechanical systems (C-MEMS) including bio-MEMS. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900359w

CuCl2 nanoparticles dispersed in activated carbon fibers for the oxygen production step of the Cu–Cl thermochemical water splitting cycle / Bhaskar Bhaduri in Industrial & engineering chemistry research, Vol. 51 N° 48 (Décembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 48 (Décembre 2012) . - pp. 15633-15641 Titre : CuCl2 nanoparticles dispersed in activated carbon fibers for the oxygen production step of the Cu–Cl thermochemical water splitting cycle Type de document : texte imprimé Auteurs : Bhaskar Bhaduri, Auteur ; Yogendra Nath Prajapati, Auteur ; Ashutosh Sharma, Auteur Année de publication : 2013 Article en page(s) : pp. 15633-15641 Note générale : Industrail chemistry Langues : Anglais (eng) Mots-clés : Production  Carbon  fiber  Activated  carbon  Nanoparticle Résumé : The thermochemical copper-chlorine (Cu―Cl) cycle is a promising method for the production of hydrogen and oxygen. It consists of four steps: chlorination, disproportionation, oxychlorination, and decomposition. In this study, we focused on the last two steps. A novel dispersion of CuCl2 nanoparticles (∼90 nm) in activated carbon microfibers (ACFs) was prepared and used for the production of oxygen through the oxychlorination of CuCl2 with steam, which was followed by the decomposition of the oxychlorinated product. The CuCl2-ACFs were prepared using the wet incipience impregnation method. After calcination of the impregnated ACF, CuCl2 nanoparticles were produced in situ on the ACF. The production rate of O2 was found to be 2.7 × 10―6 mol/g·s, which is significantly higher than the data reported in the literature. The CuCl2-ACFs prepared in this study are a potential candidate for the O2 production step of the thermochemical Cu―Cl cycle. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26710602 [article] CuCl2 nanoparticles dispersed in activated carbon fibers for the oxygen production step of the Cu–Cl thermochemical water splitting cycle [texte imprimé] / Bhaskar Bhaduri, Auteur ; Yogendra Nath Prajapati, Auteur ; Ashutosh Sharma, Auteur . - 2013 . - pp. 15633-15641. Industrail chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 48 (Décembre 2012) . - pp. 15633-15641 Mots-clés : Production  Carbon  fiber  Activated  carbon  Nanoparticle Résumé : The thermochemical copper-chlorine (Cu―Cl) cycle is a promising method for the production of hydrogen and oxygen. It consists of four steps: chlorination, disproportionation, oxychlorination, and decomposition. In this study, we focused on the last two steps. A novel dispersion of CuCl2 nanoparticles (∼90 nm) in activated carbon microfibers (ACFs) was prepared and used for the production of oxygen through the oxychlorination of CuCl2 with steam, which was followed by the decomposition of the oxychlorinated product. The CuCl2-ACFs were prepared using the wet incipience impregnation method. After calcination of the impregnated ACF, CuCl2 nanoparticles were produced in situ on the ACF. The production rate of O2 was found to be 2.7 × 10―6 mol/g·s, which is significantly higher than the data reported in the literature. The CuCl2-ACFs prepared in this study are a potential candidate for the O2 production step of the thermochemical Cu―Cl cycle. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26710602

Fe-grown carbon nanofibers for removal of arsenic(V) in wastewater / Amit Kumar Gupta in Industrial & engineering chemistry research, Vol. 49 N° 15 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 7074–7084 Titre : Fe-grown carbon nanofibers for removal of arsenic(V) in wastewater Type de document : texte imprimé Auteurs : Amit Kumar Gupta, Auteur ; Dinesh Deva, Auteur ; Ashutosh Sharma, Auteur Année de publication : 2010 Article en page(s) : pp 7074–7084 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Carbon  Nanofibers  Wastewater. Résumé : An Fe-impregnated hierarchal web of carbon fibers was synthesized and evaluated as an adsorbent for arsenic(V) removal from wastewater. The web was prepared by growing carbon nanofibers (CNFs) on the activated carbon microfibers (ACFs) by chemical vapor deposition (CVD) using Fe as a catalyst. Fe was found to play a bifunctional role in the development of the micro-/nanoweb of carbon fibers: (1) as a catalyst for growing CNFs and (2) as an adsorbent for removing arsenic(V) from water. The method of preparation consisted of impregnation of substrate ACFs with ferric chloride, calcinations followed by reduction to convert oxides of Fe to the metallic state, growth of CNFs by CVD, and subsequent mild sonication of the web to open its pore spaces. The Fe-impregnated adsorbent was tested for the removal of arsenic(V) over the concentration range of 1−50 mg/L in water under both batch and flow conditions. The results showed comparable or greater removal of arsenic(V) compared to that obtained with commercial adsorbents. The prepared adsorbent was characterized by various analytical techniques such as BET area and pore size distribution (PSD), elemental analysis, scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100392q [article] Fe-grown carbon nanofibers for removal of arsenic(V) in wastewater [texte imprimé] / Amit Kumar Gupta, Auteur ; Dinesh Deva, Auteur ; Ashutosh Sharma, Auteur . - 2010 . - pp 7074–7084. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 7074–7084 Mots-clés : Carbon  Nanofibers  Wastewater. Résumé : An Fe-impregnated hierarchal web of carbon fibers was synthesized and evaluated as an adsorbent for arsenic(V) removal from wastewater. The web was prepared by growing carbon nanofibers (CNFs) on the activated carbon microfibers (ACFs) by chemical vapor deposition (CVD) using Fe as a catalyst. Fe was found to play a bifunctional role in the development of the micro-/nanoweb of carbon fibers: (1) as a catalyst for growing CNFs and (2) as an adsorbent for removing arsenic(V) from water. The method of preparation consisted of impregnation of substrate ACFs with ferric chloride, calcinations followed by reduction to convert oxides of Fe to the metallic state, growth of CNFs by CVD, and subsequent mild sonication of the web to open its pore spaces. The Fe-impregnated adsorbent was tested for the removal of arsenic(V) over the concentration range of 1−50 mg/L in water under both batch and flow conditions. The results showed comparable or greater removal of arsenic(V) compared to that obtained with commercial adsorbents. The prepared adsorbent was characterized by various analytical techniques such as BET area and pore size distribution (PSD), elemental analysis, scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100392q

Micro-Nano Hierarchal Web of Activated Carbon Fibers for Catalytic Gas Adsorption and Reaction / Riju Mohan Singhal in Industrial & engineering chemistry research, Vol. 47 N°10 (Mai 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3700-3707 Titre : Micro-Nano Hierarchal Web of Activated Carbon Fibers for Catalytic Gas Adsorption and Reaction Type de document : texte imprimé Auteurs : Riju Mohan Singhal, Auteur ; Ashutosh Sharma, Auteur ; Nishith Verma, Auteur Année de publication : 2008 Article en page(s) : p. 3700-3707 Langues : Anglais (eng) Mots-clés : Carbon  nanofibers  (CNF)  ;  the  carbon  web Résumé : A hierarchal web of activated carbon fibers is synthesized in which carbon nanofibers (CNF) are grown on micro activated carbon fibers (ACF) used as a substrate. A bed of ACF was first impregnated with nickel nitrate hexahydrate which was subsequently reduced to metallic nickel. Catalytic chemical vapor deposition (CVD) was then carried out at 1023 K using benzene as carbon source, which resulted in the growth of CNF. Conditions of hierarchal web formation were optimized by employing two different types of reactorsa perforated tube reactor with radially outward flow of gases and a perforated disc reactor providing a parallel flow. Both of these configurations were used for carrying out reduction and CVD. Our results show that relatively larger amount and uniformity of CNF could be obtained using the perforated disc reactor. Various analytical techniques including atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed to characterize the carbon web. The resulting ACF web is a hierarchical structure, which was tested for its NO removal capability by reduction. We found these carbon structures to be more efficient compared to the original ACF or ACF impregnated with metal. En ligne : https://pubs.acs.org/doi/abs/10.1021/ie071114n [article] Micro-Nano Hierarchal Web of Activated Carbon Fibers for Catalytic Gas Adsorption and Reaction [texte imprimé] / Riju Mohan Singhal, Auteur ; Ashutosh Sharma, Auteur ; Nishith Verma, Auteur . - 2008 . - p. 3700-3707. Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3700-3707 Mots-clés : Carbon  nanofibers  (CNF)  ;  the  carbon  web Résumé : A hierarchal web of activated carbon fibers is synthesized in which carbon nanofibers (CNF) are grown on micro activated carbon fibers (ACF) used as a substrate. A bed of ACF was first impregnated with nickel nitrate hexahydrate which was subsequently reduced to metallic nickel. Catalytic chemical vapor deposition (CVD) was then carried out at 1023 K using benzene as carbon source, which resulted in the growth of CNF. Conditions of hierarchal web formation were optimized by employing two different types of reactorsa perforated tube reactor with radially outward flow of gases and a perforated disc reactor providing a parallel flow. Both of these configurations were used for carrying out reduction and CVD. Our results show that relatively larger amount and uniformity of CNF could be obtained using the perforated disc reactor. Various analytical techniques including atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed to characterize the carbon web. The resulting ACF web is a hierarchical structure, which was tested for its NO removal capability by reduction. We found these carbon structures to be more efficient compared to the original ACF or ACF impregnated with metal. En ligne : https://pubs.acs.org/doi/abs/10.1021/ie071114n

Solvent vapor-assisted imprinting of polymer films coated on curved surfaces with flexible PVA stamps / Rabibrata Mukherjee in Industrial & engineering chemistry research, Vol. 48 N° 19 (Octobre 2009) 

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Stress engineered polymeric nanostructures by self-organized splitting of microstructures / Danish Faruqui in Industrial & engineering chemistry research, Vol. 47 N°17 (Septembre 2008) 

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Tensile deformation and failure of thin films of aging laponite suspension / Asima Shaukat in Industrial & engineering chemistry research, Vol. 48 N° 17 (Septembre 2009) 

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