• Journal of The Korean Society of Clinical Toxicology
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• v.5 no.1
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• pp.43-45
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• 2007

Carbon dioxide is the fourth most abundant gas in the earth's atmosphere, and it is widely used in the chemical industry. Solid carbon dioxide is commonly known as dry ice. At low concentration, carbon dioxide appears to have little toxicological effect. At higher concentrations, however, it can produce an increased respiratory rate, tachycardia, cardiac arrhythmia, loss of consciousness, convulsion, and even death. Management of carbon dioxide poisoning requires the immediate removal of an individual from the toxic environment and administration of oxygen. It is important to know the concentration of carbon dioxide to which a patient has been exposed. We report a case of acute poisoning from solid carbon dioxide in a patient presenting with drowsiness and diminished mental capacity when she arrived in the emergency department. She recovered completely after administration of oxygen with conservative treatment.

• Carbon letters
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• v.4 no.1
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• pp.10-13
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• 2003

The structural studies of amorphous isotropic carbon prepared from pyrolysis of phenol formaldehyde resin have been carried out using X-ray diffraction. X-ray diffraction from as prepared sample at $1000^{\circ}C$ and a sample treated at $1900^{\circ}C$ revealed that both are amorphous even though there are small differences in short range order. It is found that both are graphite like carbon (GLC) with predominantly $sp^2$ hybridization. Small angle X-ray scattering results show that as prepared sample mainly consists of thin two dimensional platelets of graphitic carbon whereas they grow in thickness to become three dimensional materials of nano dimensions.

• Journal of Powder Materials
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• v.13 no.5 s.58
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• pp.305-312
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• 2006

Amorphous carbon nanotubes were synthesized by a reaction of benzene, ferrocene and Na mixture in a small autoclave at temperatures as low as $400^{\circ}C$. The resulting carbon nanotubes were short and straight, but their inner hole was filled with residual products. The addition of quartz to the reacting mixture considerably promoted the formation of carbon nanotubes. A careful examination of powder structure suggested that the nanotubes in this process were mainly formed by surface diffusion of carbon atoms at the surface of solid catalytic particles, not by VLS(vapor-liquid-solid) mechanism.

• Journal of Korean Vacuum Science & Technology
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• v.4 no.2
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• pp.50-54
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• 2000

We studied the synthesis of S $i_{1-x}$ Cx (x=0.016) epitaxial layer using ion implantation and solid phase epitaxy (SPE). The activation energy Ea was obtained for the loss of substitutional carbon using fourier transform-infrared spectroscopy (FTIR) and high-resolution x-ray diffraction (HR-XRD). In FTIR analysis, the integrated peak intensity was used to quantify the loss of carbon atoms from substitutional to interstitial sites during annealing. The substitutional carbon contents in S $i_{0.984}$ $C_{0.016}$ were also measured using HR-XRD. By dynamic simulations of x-ray rocking curves, the fraction of substitutional carbon was obtained. The effects of annealing temperature and time were also studied by comparing vacuum furnace annealing with rapid thermal annealing (RTA))))))

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.6
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• pp.620-628
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• 2014

Direct Carbon Fuel Cell(DCFC) is one of new power generation that the chemical energy of solid carbon can be converted into electrical energy directly. At the high temperature, the electrochemical reaction of the carbon takes place and the carbon reacts with oxygen to produce carbon dioxide as followed overall reaction ($C+O_2{\rightarrow}CO_2$). However, in case of using the raw coals as a fuel of DCFC, the volatile matter containing carbon, hydrogen, and oxygen produces at operating temperature. In this study, the electrochemical reaction of Adaro coal was compared with Graphite. This work focused on the electrochemical reaction of two kinds of solid carbon by Electrochemical Impedance Spectroscopy(EIS). The EIS results were estimated by equivalent circuit analysis. The constant phase element(CPE) was applied in Randle circuit to explain an electrode and fuel interface. The correlation between the fuel characteristic and electrochemical results was discussed by elements of equivalent circuit of each fuel.

• YAKHAK HOEJI
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• v.36 no.2
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• pp.120-125
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• 1992

Ths sorption and desorption properties of four different solid adsorbents were evaluated for the trace enrichment of diphenylhydantoin from biological samples. Graphitized carbon black(GCB) gave the highest adsorption coefficient. And among the organic solvents examined, methanol gave the highest desorption coefficient. Using the GCB column, the optimum elution volume of the eluting solvent was evaluated from the breakthrough curve of diphenylhydantoin. The usefulness of GCB as the solid adsorbent was examined for the solid-phase extraction of diphenylhydantoin from serum in the concentration range of $20-50\;{\mu}g/ml$.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.131-131
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• 2013

A single-layer graphene has been uniformly grown on a Cu surface at elevated temperatures by thermally processing a poly(methyl methacrylate) (PMMA) film in a rapid thermal annealing (RTA) system under vacuum. The detailed chemistry of the transition from solid-state carbon to graphene on the catalytic Cu surface was investigated by performing in-situ residual gas analysis while PMMA/Cu-foil samples being heated, in conjunction with interrupted growth studies to reconstruct ex-situ the heating process. The data clearly show that the formation of graphene occurs with hydrocarbon molecules vaporized from PMMA, such as methane and/or methyl radicals, as precursors rather than by the direct graphitization of solid-state carbon. We also found that the temperature for vaporizing hydrocarbon molecules from PMMA and the length of time the gaseous hydrocarbon atmosphere is maintained, which are dependent on both the heating temperature profile and the amount of a solid carbon feedstock are the dominant factors to determine the crystalline quality of the resulting graphene film. Under optimal growth conditions, the PMMA-derived graphene was found to have a carrier (hole) mobility as high as ~2,700 cm2V-1s-1 at room temperature, superior to common graphene converted from solid carbon.

• Membrane Journal
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• v.18 no.2
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• pp.109-115
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• 2008

To remove total dissolved solid (TDS) from wastewater, a carbon membrane system was prepared, using carbon membranes made from conductive activated carbon and poly(vinylidene fluoride) (PVDF). Using 100 ppm aqueous solutions of NaCl, $Na_2SO_4,\;MgCl_2,\;MgSO_4$, the basic properties of the carbon membranes used were studied. For the treatment of the real dye wastewater supplied from Kyungin Corp., a pilot scale carbon membrane system was also prepared, which was consisted of 240 plies of carbon membranes of $20cm{\times}20cm$ (length${\times}$width). Using the real wastewater with different TDS such as 941, 2050, 2810, 3830, 4960, 6030 ppm, prepared by the dilution of the original wastewater with pure water, the performance of the pilot scale carbon membrane system was studied. The effect of the operational conditions was studied.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2243-2248
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• 2011

Carbon-based solid acid catalyst was found to be highly efficient, eco-friendly and recyclable heterogeneous catalyst for the multicomponent reaction of dimedone, aromatic aldehydes, and a nitrogen source (ammonium acetate or aromatic amines) under solvent-free conditions, giving rise to 1,8-dioxodecahydroacridines in high yields. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.635-638
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• 2011

A simple and efficient method for the synthesis of $\beta$-amino carbonyl compounds by one-pot three-component Mannich reaction of acetophenone, aromatic aldehydes and aromatic amines using a carbon-based solid acid (CBSA), as an effective and reusable catalyst, is described. The present methodology offers several advantages such as simple procedure with an easy work-up, shorter reaction times, and high yields.