• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.2
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• pp.49-55
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• 2001

ZnO films were fabricated on p-type Si(100) wafer ITO glass and quartz glass by the sol-gel process using zinc acetate dihydrate as starting material. A homogeneous and stable solution was prepared by dissolving the zinc acetate dihydrate in a solution of 2-methoxyethanol and monoethanolamine (MEA). ZnO films were deposited by spin-coating at 2800 rpm for 25 s and were dried on a hot plate at $250^{\circ}C$ for 10 min. Crystallization of the films was carried out at $400^{\circ}C$~$800^{\circ}C$ for 1 h in air. X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), UV-vis transmittance spectroscopy, FTIR transmittance spectroscopy and Photoluminescence (PL) spectroscopy measurements have been used to study the structural and optical properties of the films. ZnO films highly oriented along the (002)plane were obtained. In all cases the films were found to be transparent (above 70%) in visible range with a sharp absorption edge at wavelengths of about 380nm, which is very close to the intrinsic band-gap of ZnO(3.2 eV). The low temperature band-edge photoluminescence revealed a complicated multi-line structure in terms of bound exciton complexes and the phonon replicas.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2609-2612
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• 2012

A simple green method was developed for rapid synthesis of silver and gold nanoparticles (AgNPs and AuNPs) has been reported using Lonicera japonica flower extract as a reducing and a capping agent. AgNPs and AuNPs were carried out at $70^{\circ}C$. The successful formation of AgNPs and AuNPs have been confirmed by UV-Vis spectro photometer, fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray Analysis (EDAX), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). To our knowledge, this is the first report where Lonicera japonica flower was found to be a suitable plant source for the green synthesis of AgNPs and AuNPs.

• Macromolecular Research
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• v.11 no.6
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• pp.501-505
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• 2003

Poly(l,6-heptadiyne) derivatives with phenoxy and 3,7-dimethyloctyloxyphenoxy substituents were synthesized using metathesis polymerization. Polymerizations using MoCl$\sub$5/ as the sole catalyst gave high yields and the resulting polymers were completely soluble in organic solvents. The polymers' structures and thermal properties were characterized using NMR and UV-Vis spectroscopy, as well as with TGA and DSC thermograms. From the analysis of the high-resolution $\^$13/C-NMR spectra, we was found that these polymers contain six-membered rings. The number-average molecular weights and polydispersities of the polymers were ca. 7.0∼20 ${\times}$ 10$^3$ and 3.1∼5.8, respectively. The glass transition temperatures of the polymers were found to be in the range 91∼159$^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2255-2260
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• 2010

In this study, some novel thiosubstituted butenyne (3a-d, 7b, 15b), butadiene (4a-b, 4d, 5a, 5c, 6b, 8e, 9c, 10b, 16b, 18e) and [3]cumulene (11a-b with isomer 3a-b, 12a with isomer 13a, 14b, 17e) compounds were synthesized from the reaction of 2H-pentachloro-1,3-butadiene with thiols. The new compounds were characterized by elemental analysis, mass spectrometry, UV-vis, IR, 1H NMR, NMR ($^{13}C$ or APT) spectroscopy.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.27-32
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• 2007

In this study, the concentrations of offensive odorous compounds seasonally emitted from the chemical plant at Chongju industrial complex in Korea were determined by the analytical methods of gas chromatography, high performance liquid chromatography and uv/vis spectroscopy. The kinds of offensive odorous compounds examined are formaldehyde, acetaldehyde, butyl aldehyde, propion aldehyde, n-valeric aldehyde, iso-valeric aldehyde, hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, trimethyl amine and ammonia. The seasonally emission levels of all odorous compounds except dimethyl sulfide at 13 sampling points of plant were lower than those of the regulation standard levels of the industrial complex in Korea. The levels were the highest in June, and lowest in December. The propion aldehyde and iso-valeric aldehyde in June and December, butyl aldehyde in December, and n-valeric aldehyde were not detected in all the three seasons at any sampling points of the plant examined. But in June, dimethyl sulfide was emitted up to 16 times than that of the regulation level.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.33-38
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• 2007

The concentrations of offensive odorous compounds emitted from the two chemical plants in Chongju and Yeosu industrial complex in Korea were determined by uv/vis spectroscopy, gas chromatography, and high performance liquid chromatography. The odorous compounds examined in this study are ammonia, trimethyl amine, formaldehyde, acetaldehyde, propion aldehyde, butyl aldehyde, n-valeric aldehyde, iso-valeric aldehyde, hydrogen sulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide. The concentrations of those were determined from the 10 sampling points of the two plants, respectively. The emission concentrations of all odorous com-pounds examined in the two plants were lower than those of the regulation standard levels of industrial complex in Korea, respectively. The propion aldehyde, n-valeric aldehyde, methyl mercaptan and dimethyl disulfide in Chongju and Yeosu plants, and butyl aldehyde and iso-valeric aldehyde in Yeosu plant were not detected at any sampling points examined.

• Journal of the Korean Home Economics Association
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• v.31 no.2
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• pp.189-203
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• 1993

The objective of this study was to investigate the changes of the fabric absorbency, stiffness and antistatic property by using a fabric softner at laundering. The samples selected in this study were cotton and polyester fabrics. The cotton fabric was treated with 1/2 times(0.035%), 1 time(0.07%), 3 times(0.21%) and 10 times(0.7%) of the commercially suggested concentration (0.07%) of the fabric softner. And polyester fabric was done at 1 time(0.07%) of that. In order to examine the effect of the fabric by using a fabric softner, the abstraction of a surface active agent and quantitative analysis was performed by using a UV/VIS Spectroscopy and the correlations among the absorbency, stiffness and antistatic property was analyzed. The results obtained from this study were as follows; 1. In the cotton fabric, fabric softner gave the degradation of absorbency, and stiffness improvement was not shown by repeated fabric softner on the cotton fabric. 2. In the polyester fabric, the absorbency increased and the stiffness in creased very slightly. Specially, it is desirable to use fabric softner on the polyester due to improvement of antistatic property.

• 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.329.1-329.1
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• 2014

In this paper, we report electrical, optical and structural properties of Al-doped zinc oxide (AZO) thin films deposited at different substrate temperatures and pressures. The films were prepared by radio frequency (RF) magnetron sputtering on glass substrates in argon (Ar) ambient. The X-ray diffraction analysis showed that the AZO films deposited at room temperature (RT) and 20 Pa were mostly oriented along a-axis with preferred orientation along (100) direction. There was an improvement in resistivity ($3.7{\times}10^{-3}{\Omega}-cm$) transmittance (95%) at constant substrate temperature (RT) and working pressure (20 Pa) using the Hall-effect measurement system and UV-vis spectroscopy, respectively. Our results have promising applications in low-cost transparent electronics, such as the thin-film solar cells and thin-film transistors due to favourable deposition conditions. Furthermore our film deposition method offers a procedure for preparing highly oriented (100) AZO films.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.140.1-140.1
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• 2011

최근 자동차용 휘발유에 메탄올을 불법 혼합시켜 유통시키는 사례가 빈번히 적발되고 있다. 정상적인 연료에 알코올이 불법 혼합될 경우, 장치 내 고무류와 금속류를 부식시키며, 독성가스인 알데하이드를 배출시키는 것으로 알려져 있다. 또한 에탄올의 경우 흡습성이 높아 자체적으로 수분을 생성시킬 수 있으며 정상 휘발유보다 증기압이 높기 때문에 밀폐공간에서 화재 및 질식의 위험이 있을 수 있다. 현재 휘발유 내에 알코올 성분을 분석하기 위한 분석법으로는 Gas Chromatography가 이용되고 있으나 고가의 장비와 긴 분석시간으로 인해서 유사석유의 판별여부가 효율적으로 이루어지지 않고 있다. 본 연구에서는 화학절 식별제인 크롬산($CrO_3$)을 이용하여 휘발유 내 알코올 성분을 정성 정량 분석하였다. 환원된 3가 크롬은 용액상에서 붉은색을 나타내므로 육안으로도 알코올의 존재여부를 간단히 확인할 수 있으며, UV-Vis Spectrophotometry를 통해 휘발유 내 알코올의 농도에 따라 흡광도값이 증가하는 것을 확인할 수 있었다.