• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.65.1-65.1
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• 2014

We present Palomar/SWIFT integral field spectroscopy of z~0.2 strong $H{\alpha}$ emitters identified in the Sloan Digital Sky Survey. The large Halpha equivalent widths as well as the huge specific star formation rates of these galaxies are comparable with that of z>4 Lyman break galaxies, thus understanding the gas kinematics and the distribution of massive stars in these systems will help to obtain a better understanding of high-redshift star forming environments and the growth of massive galaxies. We measure the velocity dispersion across the entire galaxy, estimate the number density and the spatial distribution of massive stars from the emission line morphologies. The role of minor mergers in powering star formation is investigated as an alternative to cold flow driven star formation.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.56.2-56.2
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• 2016

We present chemical abundances for about 800 red giant stars in Omega Centauri, based on medium-resolution spectra obtained using Hydra multi-fiber spectrograph at the CTIO 4-m telescope. Our sample covers 14.2 < V < 15.0, and is almost unbiased against colors (and therefore metallicity). The metallicity distribution function (MDF) constructed from our data has an overall shape and local peaks that approximately match those for brighter giant stars in Johnson et al.. We also find that more metal-rich cluster members are more concentrated in the cluster center, which is consistent with previous studies. On the other hand, we find no clear evidence for such a spatial dependence with respect to alpha elemental abundance ([${\alpha}/Fe$]).

• Natural Product Sciences
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• v.12 no.3
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• pp.122-124
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• 2006

Three flavonoid glycosides, $kaempferol-3-O-{\alpha}-L-rhamnopyranosyl-(1\;{\rightarrow}\;6)-{\beta}$-D-glucopyranoside$ or kaempferol-3-O-rutinoside (1), $isorhamnetic-3-O-{\alpha}-L-rhamnopyranosyl-(16)-{\beta}-D-glucopyranoside$ or isorhamnetin-3-O-rutinoside (2), and $quercetin-3-O-{\beta}-D-glucopyranosyl-(1 ${\rightarrow}\;2)-{\beta}-L-arabinopyranoside$ 3, the latter one being a new compound, were isolated from the methanolic extract of the aerial parts of Carrichtera annua. Mass spectrometry and 1D and 2D NMR spectroscopy allowed establishing the structure of these compounds.

• Journal of Nutrition and Health
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• v.25 no.5
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• pp.389-396
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• 1992

Provitamin A carotenoids($\alpha$- $\beta$-carotene lutein capsanthin) cintents in various red pepper and red pepper products were analyzed by HPLC and UV/VIS spectroscopy. The amounts of $\beta$-carotene and capsanthin were at its highest in powdered red pepper and lutein in red pepper leaves. There are little $\alpha$-carotene present in all samples analyzed. So vitamin A activity was calculated only from $\beta$-carotene content. Capsanthin and $\beta$-carotene contents of red pepper were higher than those of green pepper whereas lutein content of red pepper was lower than that of green pepper. whereas lutein content of red pepper was lower than that of green pepper. Vitamin A activity from colorimetric analysis was higher than that from chromatographic method and results were not generally in accordance with the vitamin A data presented in current food composition tables. Vitamin A activities in retinol equivalent(R. E. ) of green pepper red pepper powdered red pepper fermented red pepper paste and red pepper leaves were 70, 570, 1, 340, 140, 980 R. E respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.173.2-173.2
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• 2014

Thin nitride thin films were synthesized by reactive radio-frequency magnetron sputtering in the ultra high vacuum (UHV) chamber. To control the characteristics of thin films, tin nitride thin films were obtained various argon and nitrogen gas mixtures, especially low nitrogen gas ratios. Tin nitride thin films were analyzed with alpha step, scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and 4 point probe measurement. The result of alpha step and SEM showed that the thickness of thin nitride thin films were decreased with increasing nitrogen gas ratios. The metallic tin structure was decreased and the amorphous tin nitride structure were observed by XRD with higher nitrogen gas ratios. The oxidation state of tin and nitride were studied with high resolution Sn 3d and N 1s XP spectra.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.18-18
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• 1998

F First I will introduce our works how to improve the crystal growth t technique for Rare earth pnictides and chalcogenides. All these substances h have hi양1 vapor pressure and high melting print up to 3$\alpha$)()C. 까len we employ m the tungsten or molybden crucibles and enclose the sample by 빼e welding of m the lid with high current electron beam. We cannot elevate the temperature up t to 3$\alpha$)()C without suitable radiation shield because rate of radiation loss r rapidly increase in such a high temperature regions. There were no good r radiation shield but we discovered that the p-BN could work as an excellent r radiation shield after checking of the many substances. S Secondly I will show several interesting and unusual 뻐ysical properties of obtained crystals under high magnetic field, hi양1 pressure and also i including angle resolve photoemission spectroscopy. I will stress the p properties of the low carrier concentration with strong correlation on C댐, U USb and Yb4As3

• Archives of Pharmacal Research
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• v.28 no.10
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• pp.1127-1130
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• 2005

A new phenolic glucoside (1), pursargentoside, was isolated from the leaves of Prunus serrulata var. spontanea, along with three other known compounds, orobol 7-O-glucoside (2), $1{\beta}$, $2{\alpha}$, $3{\alpha}$, 24-tetrahydroxy-urs-12-en-28-oic acid (3), and chlorogenic acid (4). The structure of pursargentoside (1) was identified by spectroscopic data analysis including 1D and 2D NMR spectroscopy, as 2-O-${\beta}$-(6'-benzoyl)-glucopyranosyl o-(Z)-coumaric acid. Compounds 1, 2, and 4 exhibited ONOO- scavenging activity, whereas compound 3 was determined to be virtually inactive.

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.11-11
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• 1996

The three-dimensional structure of the carboxyl-terminal domain of the E.coli RNA polymerase $\alpha$ subunit, which is regarded as the contact site for transcription activator proteins and the promoter UP element, was determined by NMR spectroscopy. Its compact structure of four helices and two long arms enclosing its hydrophobic core shows a folding topology distinct from those of other DNA-binding proteins. (omitted)

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.71.1-71.1
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• 2016

Photometric reverberation mapping is an effective alternative to time consuming spectroscopy. It usually employs narrow bands to track the luminosity variations of broad emission lines, such as Balmer lines, and broadbands for the continuum variability. Here, we investigate the feasibility of substituting these for medium bands, with 50nm widths, that are currently being used on the SED Camera for QUasars in EArly uNiverse (SQUEAN) installed on the 2.1m Otto Struve Telescope at McDonald Observatory. Three targets with recent variability and/or short expected time lags were selected, and observed for 15 minutes each in the medium band containing $H{\alpha}$, and the two adjacent bands for continuum subtraction afterwards. Analysis shows that for one of the objects, SDSS J0350+0037, the pure $H{\alpha}$ emission line flux has a S/N ~ 12, so that variabilities up to ~ 8% are detectable. Thus, future observations using these medium bands on SQUEAN seem to be practical.

• YAKHAK HOEJI
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• v.18 no.2
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• pp.125-132
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• 1974

The by-products which were occured in the synthesis of 5-ethyl-5-phenyl barbituric acid were isolated by column chromatography combined with gas-liquid chromatography and were identified by elemental analysis, ir, nmr and mass spectroscopy ; major by-products were ethyl${\alpha}$-phenylbutyrate and ${\alpha}$-phenylbutyramide. The alkoxide which was known to be a condensation agent not only accelerated the condensation but also did the decarboxylation. And the entity concenrned with the condensation with diethyl ethylphenylmalonate was not urea but N-monosodium urea.