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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Carbon Society
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Volume & Issues
Volume 8, Issue 4 - Dec 2007
Volume 8, Issue 3 - Sep 2007
Volume 8, Issue 2 - Jun 2007
Volume 8, Issue 1 - Mar 2007
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Carbon Fibre Mesh for the Repair of Abdominal Hernias in Bovines and Caprines: A Review of Nine Clinical Cases
Kumar, Naveen ; Sharma, A.K. ; Maiti, S.K. ; Gangwar, A.K. ; Kumar, N. ;
Carbon letters, volume 8, issue 4, 2007, Pages 269~273
DOI : 10.5714/CL.2007.8.4.269
During a 4-year period (2001-2005) 09 animals were surgically treated because of abdominal wall defects (hernia). Out of 9 animals 8 were bovines and one caprine. In each case the defect was repaired with carbon fibre mesh. All the cases were successfully treated and no complication was observed up to six months postoperatively.
Development and Evaluation of Impregnated Carbon Systems Against Iodine Vapours
Srivastava, Avanish Kumar ; Saxena, Amit ; Singh, Beer ; Srivas, Suresh Kumar ;
Carbon letters, volume 8, issue 4, 2007, Pages 274~279
DOI : 10.5714/CL.2007.8.4.274
In order to understand the breakthrough behaviour of iodine vapours on impregnated carbon systems, an active carbon, 80 CTC grade,
BSS particle size and
surface area, was impregnated with metal salts such Cu, Cr, Ag, Mo and Zn, and an organic compound Triethylene diamine (TEDA) to prepare different carbon systems such as whetlerite, whetlerite/TEDA, whetlerite/KI/KOH and ASZMT. The prepared adsorbents along with active carbon were characterized for surface area and pore volume by
adsorption at liquid nitrogen temperature. These carbon systems were compared for their CT (concentration X time) values at 12.73 to 53.05 cm/sec space velocities and 2 to 5 cm carbon column bed heights. The carbon column of 5.0 cm bed height and 1.0 cm diameter was found to be providing protection against iodine vapours up to 5.5 h at 3.712 mg/L iodine vapour concentration and 12.73 cm/sec space velocity. The study clearly indicated the adsorption capacities of carbon systems to be directly proportional to their surface area values. Dead layer with all the prepared carbon systems was found to be less than 2.0 cm indicating it to be minimum bed height to have protection against
vapours. Effect of carbon bed height and flow rate was also studied. The active carbon showed maximum protection at all bed heights and flow rates in comparison to all other impregnated carbon systems, showing that only physical adsorption is responsible for the removal of iodine vapours.
Impregnated Active Carbon-Shelf Life Studies and Its Evaluation Against Cyanogen Chloride with and without Canister
Singh, Beer ; Saxena, Amit ; Srivastava, Avanish Kumar ; Dubey, Devendra Kumar ; Gupta, Arvind Kumar ;
Carbon letters, volume 8, issue 4, 2007, Pages 280~284
DOI : 10.5714/CL.2007.8.4.280
Samples of active carbon of
surface area were impregnated with ammoniacal salts of copper, chromium and silver, with and without triethylenediamine. The samples of impregnated carbon were aged at
, with and without 90% RH (relative humidity), for a little more than one year and chemically evaluated periodically. Initially copper (II) and chromium (VI) reduced very fast in the samples in humid atmosphere to the extent of 30% and 60% respectively in four months. These values were found to be unaffected by the presence of triethylenediamine (TEDA) indicating that the chemical did not retard the reduction process of chromium (VI) and copper (II). However, in the absence of humidity the reduction of the impregnants was significantly less (10-12%, w/w) in four months. It was quite evident; therefore, that the moisture was mainly responsible for the reduction of chromium (VI) and copper (II) species in impregnated carbons. The prolonged ageing of the samples with and without triethylenediamme after four months with and without humid atmosphere showed that the extent of reduction of chromium (VI) was very low, i.e. 5-10% and of copper (II) was 2-25%. Silver is not reduced due to carbon, as it remained unchanged in concentration on storage. The impregnated carbon samples (100 g) without triethylenediamine, which were aged at room temperature for 5 years in absence of humidity and unaged when evaluated against cyanogen chloride (CNCl) at a concentration of 4 mg/L and airflow rate of 30 lpm showed a high degree of protection (80- 110 minutes).
Carbon Material from Natural Sources as an Anode in Lithium Secondary Battery
Bhardwaj, Sunil ; Sharon, Maheshwar ; Ishihara, T. ; Jayabhaye, Sandesh ; Afre, Rakesh ; Soga, T. ; Sharon, Madhuri ;
Carbon letters, volume 8, issue 4, 2007, Pages 285~291
DOI : 10.5714/CL.2007.8.4.285
Carbon materials of various morphologies were synthesized by pyrolysis of Soap-nut seeds (Sapindus mukorossi), Jack Fruit seeds (Artocarpus heterophyllus), Date-seeds (Phoenix dactylifera), Neem seeds (Azadirachta indica), Tea leaves (Ehretia microphylla), Bamboo stem (Bambusa bambus) and Coconut fiber (Cocos nucifera), without using any catalyst. Carbon materials thus formed were characterized by SEM XRD and Raman. Carbon thus synthesized varied in size (in
) but all showed highly porous morphology. These carbon materials were utilized as the anode in Lithium secondary battery. Amongst the various precursors, carbon fibers obtained from Soap-nut seeds (Sapindus mukorossi) and Bamboo stem (Bambusa bambus), even after
cycles, showed the highest capacity of 130.29 mAh/g and 92.74 mAh/g respectively. Morphology, surface areas and porosity of carbon materials obtained from these precursors were analyzed to provide interpretation for their capacity to intercalate lithium. From the Raman studies it is concluded that graphitic nature of carbon materials assist in the intercalation of lithium. Size of cavity (or pore size of channels type structure) present in carbon materials were found to facilitate the intercalation of lithium.
An XPS Study of Oxyfluorinated Multiwalled Carbon Nano Tubes
Yun, Seok-Min ; Kim, Ju-Wan ; Jung, Min-Jung ; Nho, Young-Chang ; Kang, Phil-Hyun ; Lee, Young-Seak ;
Carbon letters, volume 8, issue 4, 2007, Pages 292~298
DOI : 10.5714/CL.2007.8.4.292
In order to investigate functional groups on the surface of Multi-walled Carbon Nanotubes (MWCNTs) induced by oxyfluorination, XPS (X-ray photoelectron spectroscopy) analysis was carried out. All core level spectra of MWCNTs were deconvoluted to several Pseudo-Voigt functions (sum of Gaussian-Lorentzian functions). Both O1s and F1s binding energy of oxyfluorinated MWCNTs shifted high value as increment of fluorine mixing ratio. The carbon-fluorine covalent bonding concentration increased as increment of fluorine mixing ratio. The shape and intensity of OF10-MWCNTs are similar with those of as-received MWCNTs. However, the intensity and binding energies of main peak position of OF20-MWCNTs and OF30-MWCNTs were dramatically increased by oxyfluorination.
Removal of Pesticide (Oxamyl) from Water using Activated Carbons Developed from Apricot Stones
El-Nabarawy, Th. ; Sayed Ahmed, S.A. ; Youssef, A.M. ;
Carbon letters, volume 8, issue 4, 2007, Pages 299~306
DOI : 10.5714/CL.2007.8.4.299
Four stream- activated carbons were prepared by carbonizing apricot stones at
followed by gasification with steam at
to burn-off's=17, 32, 49 and 65%. The textural parameters of these activated carbons were determined from nitrogen adsorption results at 77 K. The total pore volume and the mean pore radius increased with the increase of % burn-off whereas the surface area increased with the increase of burn- off from 17 to 32 and further to 49%. Further increase of burn-off to 65% was associated with a considerable decrease in surface area as a result of pronounced pore widening due to pore erosion. The surface pH values of the carbons investigated range between 7.1 and 8.2. The adsorption of oxamyl onto the activated carbon followed pseudo-second order kinetics and the equilibrium adsorption isotherms fitted Langmuir adsorption model. The adsorption of oxamyl proved to be of the physical type and took place in non-micropores. The amount of oxamyl adsorbed expressed as
depends to a large extent to the surface area located in non-micropores
, where a straight line relationship passing through the origin was obtained.
Evaluation of Bulk-Sensitive Structural Characteristics of Oxidized Single-Walled Carbon Nanotubes using Solution Phase Optical Spectra
Lee, Geon-Woong ; Bang, Dae-Suk ; Cho, Dong-Hwan ; Kumar, Satish ;
Carbon letters, volume 8, issue 4, 2007, Pages 307~312
DOI : 10.5714/CL.2007.8.4.307
A method for evaluating bulk sensitive structural characteristics of unpurified, as-purified, and acid treated single walled carbon nanotubes (SWNTs) was described in the present study. The optical spectra of SWNT solutions were well resolved after prolonged sonication and they were correlated to the diameter and the distribution of nanotubes. The acid-treated SWNTs were similar to as-purified SWNTs in terms of catalyst residue, radial breathing mode (RBM) in the Raman spectra, and the first band gap energy of semiconducting tubes in the optical spectra. The solution phase optical spectra were more sensitive to changes in the small diameter and metallic tubes after the acid treatment than were the RBM spectra.
Stabilization, Carbonization, and Characterization of PAN Precursor Webs Processed by Electrospinning Technique
Cho, Chae-Wook ; Cho, Dong-Hwan ; Ko, Young-Gwang ; Kwon, Oh-Hyeong ; Kang, Inn-Kyu ;
Carbon letters, volume 8, issue 4, 2007, Pages 313~320
DOI : 10.5714/CL.2007.8.4.313
In the present study, electrospun PAN precursor webs and the stabilized and carbonized nanofiber webs processed under different heat-treatment conditions were characterized by means of weight loss measurement, elemental analysis, scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), thermogravimentric analysis (TGA), and X-ray diffraction (XRD) analysis. The result indicated that stabilization and carbonization processes with different temperatures and heating rates significantly influenced the chemical and morphological characteristics as well as the thermal properties of the stabilized and then subsequently carbonized nanofiber webs from PAN precursor webs. It was noted that the filament diameter and the carbon content of a carbonized nanofiber web as well as its weight change may be effectively monitored by controlling both stabilization and carbonization processes.
Zeta-potentials of Oxygen and Nitrogen Enriched Activated Carbons for Removal of Copper Ion
Park, Kwan-Ho ; Lee, Chang-Ho ; Ryu, Seung-Kon ; Yang, Xiaoping ;
Carbon letters, volume 8, issue 4, 2007, Pages 321~325
DOI : 10.5714/CL.2007.8.4.321
The oxygen and nitrogen enriched activated carbons were obtained from modification of commercial activated carbon by using nitric acid, sodium hydroxide and urea. Zeta-potentials of modified activated carbons were investigated in relation to copper ion adsorption. The structural properties of modified activated carbons were not so much changed, but the zeta-potentials and isoelectric points were considerably changed. The zeta-potential of nitric acid modified activated carbon was the most negative than other activated carbons in the entire pH region, and the
was shifted from pH 4.8 to 2.6, resulted in the largest copper ion adsorption capacities compare with other activated carbons in the range of pH 3~6.5. In case of urea modified activated carbon, copper ion adsorption was larger than that of the as-received activated carbon from pH 2 to pH 6.5 even though the
was shifted to pH 6.0, it was due to the coordination process operated between nitrogen functional groups and copper ion. The adsorption capacity of copper ion was much influenced by zeta-potential and
of carbon adsorbent.
The Characterization of the Resin Bonded Graphite Composite Bipolar Plate using Isotropic Graphite Powder for PEM Fuel Cell
Cho, Kwang-Youn ; Riu, Doh-Hyung ; Hui, Seung-Hun ; Kim, Hong-Suk ; Chung, Yoon-Jung ; Lim, Yun-Soo ;
Carbon letters, volume 8, issue 4, 2007, Pages 326~334
DOI : 10.5714/CL.2007.8.4.326
In this study, graphite composites were fabricated by warm press molding method to realize commercialization of PEM fuel cells. Graphite composites have been considered as alternative economic materials for bipolar plate of PEM fuel cells. Graphite powder that enables to provide electrical conductivity was selected as the main substance. The graphite powder was mixed with phenolic resin and the mixture was pressed using a warm press method. First of all, the graphite powder was pulverized with a ball mill for the dense packing of composite. As the ball milling time increases, the average size of particles decreases and the size distribution becomes narrow. This allows for improvement of the uniformity of graphite composite. However, the surface electrical resistivity of graphite composite increases as the ball milling time increases. It is due to that graphite particles with amorphous phase are generated on the surface due to the friction and collision of particles during pulverizing. We found that the contact electrical resistivity of graphite particles increases as the particle size decreases. The contact electrical resistivity of graphite powders was reduced due to high molding pressure by warm press molding. This leads to improvement of the mechanical properties of graphite composite. Hydrogen gas impermeability was measured with the graphite composite, showing a possibility of the application for bipolar plate in fuel cell. And, I-V curves of the graphite composite bipolar plate exhibit a similar performance to the graphite bipolar plate.
Electrochemical Performance of Carbon/Silicon Composite as Anode Materials for High Capacity Lithium Ion Secondary Battery
Kim, Taek-Rae ; Wu, Jing-Yu ; Hu, Quan-Li ; Kim, Myung-Soo ;
Carbon letters, volume 8, issue 4, 2007, Pages 335~339
DOI : 10.5714/CL.2007.8.4.335
Carbon/silicon composites were synthesized by mixing silicon powders with petroleum pitch and subsequent heat-treatment. The resultant composites were composed of carbon and nano-size crystalline silicon identified by XRD and EDX. FIB images and SEM images were taken respectively to detect the existence of silicon impregnated in carbon and the distribution of silicon on the carbon surface. The obtained carbon/silicon materials were assembled as half cell anodes for lithium ion secondary battery and their electrochemical properties were tested. The pitch/silicon composite (3 : 1 wt. ratio) heat treated at
and mixed with 55.5 wt.% of graphite showed relatively good electrochemical properties such as the initial efficiency of 78%, the initial discharge capacity of 605 mAh/g, and the discharge capacity of 500 mAh/g after 20 cycles.
Patent Trends of Carbonaceous Materials for Hydrogen Storage (II): Qualitative Analysis
Park, Soo-Jin ; Kim, Byung-Joo ; Lee, Young-Seak ;
Carbon letters, volume 8, issue 4, 2007, Pages 340~348
DOI : 10.5714/CL.2007.8.4.340