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Abstract  

Corn cobs obtained as waste from the corn industry, were analyzed by a TG-DTA unit in an atmosphere of flowing nitrogen. The carbonaceous products so formed were then produced on a preparative scale and activated chemically using potassium hydroxide. This resulted in the formation of a carbon with a very high surface area. The active carbon produced was then examined using thermal analysis in the temperature jump mode on a thermogravimetry unit. From this data the kinetics of degradation of the active carbon was determined using zero order rate kinetics. The pore structure of the active material was also examined using SEM. TheE a for activated corn cobs was found to be 106 kJ mol−1.

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Abstract  

Thermal analysis has been used to determine the impact of heating on the decomposition reaction of two Moroccan oil shales between ambient temperature and 500C. During pyrolysis of raw oil shale, the residual organic matter (residual carbon) obtained for both shales depends on the heating rate (5 to 40C min-1). Three stages characterize the overall process: the concentration of carbonaceous residue decreases with increase of heating rate, become stable around 12C min-1 and continue to decrease at higher heating rates. Activation energies were determined using the Coats-Redfern method. Results show a change in the reaction mechanism at around 350C. Below this temperature, the activation energy was 41.3 kJ mol-1 for the decomposition of Timahdit, and 40.5 kJ mol-1 for Tarfaya shale. Above this temperature the respective values are 64.3 and 61.3 kJ mol-1. The reactivity of Timahdit and Tarfaya oil shale residual carbon prepared at 12C min-1 was subject to a dynamic air atmosphere to determine their thermal behaviour. Residual carbon obtained from Tarfaya oil shale is shown to be more reactive than that obtained from Timahdit oil shale.

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Various carbon dust particles

Studies on thermal behaviour

Journal of Thermal Analysis and Calorimetry
Authors: Sonja Eichholz, Martin Lerch, Michael Heck, and Dirk Walter

dust particles to human health in more detail, state-of-the-art characterization methods are required. Here, electron microscopy and thermal analysis combined with gas analysis may be taken into account [ 2 , 3 ]. A comparison of diesel soot and carbon

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Orvosi Hetilap
Authors: Béla Sebők, Gábor Kiss, Péter János Szabó, Dániel Rigler, László Milán Molnár, Gábor Dobos, Ferenc Réti, Hajnal Szőcs, F. Árpád Joób, Kinga Körmöczi, and György Szabó

Szabó, G., Barabás, J., Németh, Z., et al.: Carbon-carbon implants in the oral and maxillofacial surgery – Part 1. [Karbon/karbon implantátumok az arc- és állcsontsebészetben – 1. rész.]. Orv. Hetil

Open access

Introduction Palladium supported carbon materials (activated carbon, carbon fibres, carbon black, nanotubes) are highly suitable catalysts for several chemical and electrochemical reactions [ 1 – 13 ]. Relevant concerns

Open access
Central European Geology
Authors: Leonel da Silveira Lobo Sternberg, Carlos Augusto Ramos e Silva, and Pablo Bezerra Dávalos

T.T.T. Hoa S.E. Bunn V.M. Fry 2004 Dominant sources of dietary carbon and nitrogen for shrimp

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Orvosi Hetilap
Authors: György Szabó, József Barabás, Zsolt Németh, and Sándor Bogdán

Blazewicz, M.: Carbon materials in the treatment of soft and hard tissue injuries. Eur. Cells Mater., 2001, 2 , 21–29. Blazewicz M

Open access
Nanopages
Authors: S. Talapatra, T. Kim, B. Q. Wei, S. Kar, R. Vajtai, G. V. S. Sastry, M. Shima, D. Srivastava, and P. M. Ajayan

We report on the room temperature ferromagnetism observed in heat treated nanocrystalline diamonds. By systematic annealing of nanocrystalline diamond, graphitic nanoclusters having finite magnetization with well-defined hysteresis and coercivity, and a Curie temperature (TC) well above 400 K (estimated TC ~ 590 K), were synthesized. Using detailed analysis of the structural modification at various annealing stages, with Raman Spectroscopy and High Resolution Transmission Electron Microscopy, we show that the carbon bonding configuration has important consequence to the observed magnetism in these samples. These findings could lead to controlled fabrication of metal free magnetic carbon system.

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carbon materials can be synthesized from waste materials. There are different methods for synthesizing carbon materials. However, many of these techniques are highly complicated, toxic, and expensive. Therefore, the search is on for cheap, abundant

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Journal of Thermal Analysis and Calorimetry
Authors: Eudes Lorençon, Rodrigo G. Lacerda, Luiz O. Ladeira, Rodrigo R. Resende, André S. Ferlauto, Ulf Schuchardt, and Rochel M. Lago

Introduction Carbon nanotubes (CNTs) have been intensely investigated due to their unique chemical, mechanical, and electrical behavior. The inherent properties of CNTs make them versatile supports for metallic nanoparticles

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