• Journal of The Korean Astronomical Society
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• v.29 no.2
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• pp.255-268
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• 1996

We present VR CCD photometry and long-slit spectroscopy of a late type spiral galaxy NGC 7678. The grey scale images and isophotal maps illustrate the presence of a weak bar from which spiral arms emerge. There are many HII regions along the spiral arms, but bright giant HII regions are more concentrated in the massive southern arm. The bright compact nucleus of NGC 7678 is bluer than bulge and bar. The spectral features of the nucleus and HII regoins are very similar but the nuclear spectra shows higher $[NII]{\lambda}6583/H_\alpha$ than those of the HII regions. The nucleus of NGC 7678 seems to be intermediate type between HII region nulcei and LINERs by the ratio of $[NII]{\lambda}6583/H_\alpha$, but it is more likely to be HII region-like nucleus if we consider the $[NII]{\lambda}6716,6731/H_\alpha$ together. The star formation rate is estimated to be about $0.2 M_\bigodot\;yr^{-1}$ based on the $H_\alpha$ flux.

• Journal of the Korean Ceramic Society
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• v.24 no.5
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• pp.447-452
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• 1987

${\alpha}$-Al2O3 powder was produced at 1000$^{\circ}C$ by the boehmite sol-gel process with seeding 2 wt% ${\alpha}$-Al2O3. The processes and mechanisms of fornation of ${\alpha}$-Al2O3 was investigated using DTA/TG, XRD, TR spectroscopy and thermodynamic analysis. The specific surface area of the obtained ${\alpha}$-Al2O3 was 16.3㎡/g.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.474-479
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• 1992

Molecular interaction between ${\alpha}$-cyclodextrin and aspirin was studied by UV, $^2H$-NMR and $^2H$-NMR spectroscopy analyses for solution complex and by FT-IR analyses for solid complex. The inclusion structure provides a basic understanding of the aspirin and ${\alpha}$-cyclodextrin interaction.

• Journal of the Korean Vacuum Society
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• v.7 no.4
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• pp.361-367
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• 1998

$\alpha$-Sexithiophene ($\alpha$-6T) thin films were deposited by organic molecular beam deposition (OMBD) technique. The $\alpha$-6T was synthesized and purified by the sublimation method. The thin films of the $\alpha$-6T were deposited under various deposition conditions. The effects of deposition rate, substrate temperature, and vacuum pressure on the formation of these films have been studied. The molecular orientation, crystallinity, and surface morphology of $\alpha$-6T films were investigated with angle-resolved UV/visible absorption spectroscopy, X-ray diffractometry (XRD), and atomic force microscopy (AFM). It was found that the crystalline structure of $\alpha$-6T films was monoclinic and independent uppon substrate temperature, deposition rate, and deposition pressure. On the other hand, the $\alpha$-6T molecules in the film deposited at a low deposition rate, higher substrate temperature, and under a high vacuum tended to be aligned perpendicular to the substrate.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.245-246
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• 2011

Emission lines ratios were used for diagnostics of and excited level densities in low-temperature plasmas. In this work, an optical emission spectroscopy (OES) was used to determine the electron temperature and metastable level densities in low-pressure inductively coupled plasma. The emission spectroscopy method was based on a simple collisional-radiative model. The selected lines of the Ar(4p to 4s) were influenced by the radiation trapping at relatively high pressures where the plasma become optically thick. To quantify this effect, a pressure dependence factor ${\alpha}$(P) was derived by using corrections for the measured intensities. It was found that the lower metastable level densities were obtained when ${\alpha}$(P) increased with the increasing discharge pressure. The effect of non-Maxwellian electron energy distribution functions (EEDFs) on the metastables was also presented and discussed.

• Journal of the Korean Magnetics Society
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• v.8 no.1
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• pp.6-12
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• 1998

Fe-N(iron-nitrogen) crystal phases were prepared by nitrogen ion implantation into $\alpha$-Fe foil with Plasma Source Ion Implantation (PSII). Ion implantation time of sample is treated 15 minutes(FeN15) and 30 minutes (FeN30). The nitrogen depth profiles measured by Auger electron spectroscopy (AES) were determined to be about 12000 $\AA$ and 4000 $\AA$ for the samples of FeN15 and FeN30, respectively. The results of vibrating sample magnetometer (VSM) show that the saturation magnetization of the samples of as-implanted FeN15 and FeN30 was higher than that of pure $\alpha$-Fe foil, which may be owing to $\alpha$'-$Fe_8N$ or $\alpha$"-$Fe_{16}N_2$ phases. Accordingly this study shows the possibility of the partial formation of $\alpha$' or $\alpha$" phase in iron nitrogen produced by PSII method.II method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.11
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• pp.103-112
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• 2011

This paper is tried to analysis the optical emission spectroscopy related to the position of inductive load coil and flow rates of methane and oxygen in the RF inductive plasma process. According to the position of load coil, peak of $H_{\alpha}$, $H_{\beta}$, and CH were appeared strongly at the middle position of the coil and it decreased both direction. The electron temperature was approximately 0.9[eV] at that position. Emission intensities of $H_{\alpha}$, $H_{\beta}$, and CH increased linearly by increasing input power. In addition, intensities of $H_{\alpha}$ and $H_{\beta}$ increased by increasing the flow rate of oxygen. It might be ascribed that the oxygen species were bonded with $C_nH_m$ by suppressing the combination with hydrogen atoms. Consequently, the optimal position of the inductive coil is decided to the intermediate position between 4th and 5th turns, the wanted carbon thin-film is possible to deposit by controlling flow rates of methane and oxygen.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3675-3678
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• 2010

In-situ X-ray absorption spectroscopy (XAS) was used to elucidate the structural variation of $\alpha-MoO_3$ electrode upon discharge/charge reaction in a lithium ion battery. According to the XAS analysis, hexavalent Mo atoms in $\alpha-MoO_3$ framework are reduced as the amount of intercalated lithium ions increases. As lithium de-intercalation proceeds, most of pre-edge peaks are restored again. However, according to the Fourier transforms of the extended X-ray absorption fine structure (EXAFS) spectra, lithium de-intercalation reaction is partially irreversible upon the charge reaction, which is one of the main reasons why the capacity of $\alpha-MoO_3$ electrode decreases upon successive discharge/charge cycles.

• Journal of the Korean Applied Science and Technology
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• v.10 no.1
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• pp.31-38
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• 1993

Anionic polyolic surfactants, ${alpha}-sulfo$ fatty acids that straight long chain alkyl group has from 12 to 18 hydrocarbon numbers, was synthesized with sulfur trioxide-dioxane complex to good yields. New sodium ${alpha}-sulfo$ long chain fatty acid monoglyceride were obtained by reaction that the ketalificaticn and esterification of glycerol, acetone and ${alpha}-sulfo$ long chain fatty acid and hydrolysis respectively. These reaction products separated by column chromatography and their $R_{f}$ values($R_{f}{\times}100$) were 19, 21, 24 and 26 respectively. These compounds were identified by infrared spectroscopy and $^{1}H$ NMR spectroscopy.

• Journal of Radiation Protection and Research
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• v.17 no.1
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• pp.31-41
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• 1992

A study for the evaluation of selected filter media that need further characterization particularily in the context of alpha measurements of radon progeny has been carried out by investigating physical characteristics and using the alpha spectroscopy. Physical characteristics was investigated by electrostatic charging and mechanical strength of filters, and then pressure drop before and after sampling was tested. Alpha spectroscopy was used to analyze the energy spectra from the deposition of radon progeny into filters. The results of the assessment showed that the newer filter types do not have a great advantage over the 'old standard' Millipore type AA. But Metricel DM-800 is recommended for those situations where electrostatic charging is a problem. Also this method will be used more effective for the evaluation of new developing filters in future.