• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.28.1-28.1
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• 2011

We deposited the carbon films on Ni substrates by thermal atomic layer deposition (th-ALD), for the first time, using carbon tetrabromide ($CBr_4$) precursors and H2 reactants at two different temperatures (573 K and 673 K). Morphology of carbon films was characterized by scanning electron microscopy (SEM). The carbon films having amorphous carbon structures were analyzed by X-ray photoemission spectroscopy (XPS) and Raman spectroscopy. As the working temperature was increased from 573 K to 673 K, the intensity of C1s spectra was increased while that of O1s core spectra was reduced. That is, the purity of carbon films containing bromine (Br) atoms was increased. Also, the thin amorphous carbon films (ALD 3 cycle) were transformed to multilayer graphene segregated on Ni layer, through the post-annealing and cooling process.

• Journal of Environmental Science International
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• v.14 no.12
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• pp.1113-1117
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• 2005

Gamma-ray treatment was used to exterminate nematodes, which were harmful to agriculture When gamma-ray at the dose range of $5\~75$ kGy was irradaidated, nematodes were reduced by $40\~50\%$ When irradiated over 30 kGy, almost nematodes were non-mobile and fluorochromatic reactions showed that $60\;\~80\%$ of nematodes with non-mobility died after irradiation. The results of electron spin resonance spectroscopy suggested that radicals generated by radiolysis could damage to nematodes.

• Journal of the Korean Magnetic Resonance Society
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• v.5 no.1
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• pp.13-18
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• 2001

Natural alpha radiation produced a stable defect center to certain minerals. Electron Paramagnetic Resonance(EPR) spectroscopy is a powerful tool f3r quantifying this defect center. EPR method has been applied to trace alpha-radiation effect around the uranium ore deposit. The results show that EPR technique can be used to measure rapidly and nondestructively the defect center produced by natural alpha radiation. In general, a good correlation was achieved between defect center concentration and actinide elements(U, Th). These results imply that the concentration of defect center is dependent on the alpha radiation dose over long time scale.

• Journal of Nutrition and Health
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• v.4 no.3
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• pp.1-4
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• 1971

Zinc is an essential trace element. Previos methods for the determination of zinc in serum have been difficult and reported findings must be treated with caution. The normal range of zinc in serum varies significantly according to different methods and author. The scope of this work was to establish the normal range of zinc in serum values in healthy Korean persons. Methods are described for the determination of zinc in serum diluted ten-fold with deionised water using Hitachi Model 207, atomic absorption spectrophotometer. The values of zinc in serum of 23 healthy Korean persons by atomic absorption spectroscopy ranged from 87.6 to $131.2\;{\mu}g/100\;ml$ with the mean value $109.1\;{\mu}g/100\;ml$ and standard deviation 10.86. In this method, satifactory result was obtained with regard to the coefficient variation and recoveries of added zinc in the measurenents.

• Journal of the Korean Chemical Society
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• v.41 no.2
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• pp.113-116
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• 1997

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.167-170
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• 2013

Lignin can be a valuable natural chemical resource. Structurally, lignin is a three-dimensional polymer made up of condensed C-C bonds and some ether linkages, most of which are not readily degraded. In this study, lignin carbonization under various electron beam pretreatment conditions was characterized through a thermogravimetric analysis (TGA), X-ray diffraction (XRD) and Raman spectroscopy. Lignin stabilization was controlled by various doses of electron beam irradiation corresponding to 50, 100, 200, 500 and 1,000 kGy; the carbonization process was performed under a nitrogen gas atmosphere at $1000^{\circ}C$ for 1 h. The TGA results showed that a 1,000 kGy lignin dose increased the residue weight from 39.96% to 45.23%, compared to non-irradiated lignin. This observation is in agreement with the XRD and Raman spectroscopy results, in which the two theta degrees and the degree of crystallization were improved by increasing the electron beam irradiation.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.443-444
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• 2009

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.373-373
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• 2012

We fabricated conductive zinc oxide (ZnO) thin film at low temperature by UV-enhanced atomic layer deposition. The atomic layer deposition relies on alternate pulsing of the precursor gases onto the substrate surface and subsequent chemisorption of the precursors. In this experiment, diethylzinc (DEZ) and $H_2O$ were used as precursors with UV light. The UV light was very effective to improve the conductivity of the ZnO thin film. The thickness, transparency and resistivity were investigated by ellisometry, UV-visible spectroscopy and Four-point probe.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.581-584
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• 1998

TiN thin films were grown on (100) Si substrate by atomic layer epitaxy at 130 - $240^{\circ}C$ using TEMAT and NH3 as precursors. Reactants were injected into the reactor in sequence of TEMAT precursor vapor pulse, N2 purging gas pulse, NH3 gas pulse and N2 purging gas pulse so that gas-phase reactions could be removed. The films were characterized by means of x-ray diffraction(XRD), 4-point probe, atomic force microscopy(AFM) and auger electron spectroscopy(AES).

• Journal of the Optical Society of Korea
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• v.13 no.1
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• pp.60-64
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• 2009

We attempted the first measurement of the spectral width of the nickel-like molybdenum x-ray laser (${\lambda}\;=\;18.895\;nm$) by use of a high-resolution spectrometer in order to determine the strength of the magnetic field required for the generation of a circularly polarized x-ray laser. The spectral width was measured to be ${\Delta}{\lambda}\;=\;18\;m{\AA}$ under the substantial lasing condition. The magnetic field required for the generation of a circularly polarized x-ray laser was 40 T. The splitting of the x-ray laser line was clearly obtained under 15 T external magnetic field. The strength of the magnetic field estimated from the splitting of the x-ray laser line was large compared with the external magnetic field. It implies that there might be an alternative mechanism for enhancement of the magnetic field in the gain medium plasma.