• 청정기술
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• 제26권4호
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• pp.251-256
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• 2020

The biocompatibility and plasmonic properties of Au nanoparticles make them useful for photothermal therapy, drug delivery, imaging, and many other fields. This study demonstrated a novel, facile, economic, and green synthetic method to produce gold nanoparticles. Gold nanoparticles (AuNPs) with spherical and triangular shapes were effectively synthesized using only Schisandra chenesis fruit extract as the capping and reducing agent. The shape of the AuNPs could be engineered simply by adjusting the molar concentration of HAuCl4 in the reaction mixture. The as-synthesized AuNPs were characterized using UV-VIS spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and energy dispersive X-ray analysis (EDXA). This study revealed that by using the HAuCl4 concentration in the AuNP synthesis, the shape and size of the AuNPs could be controlled by the concentration of HAuCl4 and Schisandra chinensis fruit extract as a surfactant. The as-synthesized AuNPs samples had sufficient colloidal stability without noticeable aggregation and showed the predominant growth of the (111) plane of face-centered cubic gold during the crystal growth. The catalytic efficiency of the AuNPs synthesized using Schisandra chenesis fruit extract was examined by monitoring the catalytic reduction of 4-nitrophenol to 4-aminophenol using Ultraviolet-visible spectroscopy (UV-Vis spectroscopy). The synthesized AuNPs showed good catalytic activity to reduce 4-nitrophenol to 4-aminophenol, revealing their practical usefulness.

• 한국결정성장학회지
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• 제29권6호
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• pp.379-382
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• 2019

금 나노 입자의 합성은 폴리바이닐피롤리던(PVP)의 계면 활성제로 아스코르브 산(AC)에 의한 골드 솔트의 환원을 통해 수용액 환경을 만들었다. pH 제어에 의해 4 내지 20 nm의 크기 범위를 갖는 고분 산성 금 입자를 고수율로 제조하였다. 합성된 금 나노 입자의 구조적 및 광학적 특성은 투과 전자 현미경(TEM) 및 UV-vis 분광법에 의해 특성화되었다. 제조된 나노 입자는 효율적인 표면 강화 라만 산란(SERS) 특성을 나타내었고, 이들의 SERS 활성은 크기에 의존한다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.418-418
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• 2012

We fabricated a new type of hybrid film using molecular layer deposition (MLD). The MLD is a gas phase process analogous to atomic layer deposition (ALD) and also relies on a saturated surface reaction sequentially which results in the formation of a monolayer in each sequence. In the MLD process, polydiacetylene (PDA) layers were grown by repeated sequential surface reactions of titanium tetrachloride and 2,4-hexadiyne-1,6-diol with ultraviolet (UV) polymerization under a substrate temperature of $100^{\circ}C$. Ellipsometry analysis showed a self-limiting surface reaction process and linear growth of the hybrid films. Polymerization of the hybrid films was confirmed by infrared (IR) spectroscopy and UV-Vis spectroscopy. Composition of the films was confirmed by IR spectroscopy and X-ray photoelectron (XP) spectroscopy. The titanium oxide cross-linked polydiacetylene (TiOPDA) hybrid films exhibited good thermal and mechanical stabilities.

• 분석과학
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• 제13권3호
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• pp.282-290
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• 2000

본 연구는 390nm 이하에서 자외선 흡수가 완벽한 폴리카보네이트(광학용)에 첨가된 각종 첨가제를 아세톤으로 추출하거나 용해-침전 방식으로 분리하여 분석하는 것이다. 분리된 첨가제를 정성적으로 분석하기 위해 자외선흡광광도계, FT-IR 및 HPLC로 분석하였다. 분리된 물질은 광안정제 및 산화방지제(1차 및 2차)등의 첨가제와 단량체 및 올리고머가 함유된 복잡한 혼합물로 추정할 수 있다. 분리된 첨가물을 Bondapak $C_{18}$ 칼럼, 메탄올 이동상, PDA (Photodiode Array) 검출기를 사용한 역상(reversed phase, RP) HPLC 분석을 통해 비스페놀 A, Irganox 1010, Cyasorb UV-5411 성분들을 확인할 수 있있다. 또한, 자외선 흡광도를 이용한 정량분석을 통해 폴리카보네이트에 광안정제인 Cyasorb UV-5411가 0.12중량% 함유된 것을 알 수 있었다.

• 한국응용과학기술학회지
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• 제31권3호
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• pp.337-344
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• 2014

이 논문은 온도차에 따라 변화되는 이온성 액체와 낮은 밴드갭을 갖는 고분자인 poly(2-heptadecyl-4-vinylthieno[3,4-d]thiazole)(PHVTT) 간의 상호작용 및 고분자의 거동을 조사하였다. 이온성 액체는 methyl imidazolium chloride([MIM]Cl), butyl methyl imidazolium chloride([BMIM]Cl), tri-butyl methyl ammonium methyl sulfate([TBMA][ $MeSO_4$])를 사용하였으며, 21, 28, 32, $37^{\circ}C$로 온도를 변화시키며 상호작용의 변화를 UV-vis spectroscopy, FT-IR spectroscopy, photoluminescence spectroscopy를 통해 확인한 결과 이온성 액체인 [MIM]Cl, [TBMA][$MeSO_4$]와 PHVTT의 상호작용은 점차 약해짐을 확인할 수 있었지만, [BMIM]Cl은 온도 변화에 따른 상호작용의 변화를 보이지 않았다.

• 한국산학기술학회논문지
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• 제11권1호
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• pp.29-36
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• 2010

합성과 천연 에메랄드의 열처리에 따른 분광특성 변화를 가시광선과 적외선 분광분석으로 관찰하였다. X-선 형광분석 결과 flux 합성 에메랄드에서는 Mo과 Co이 검출 되었고, hydrothermal 합성 에메랄드에서는 Cl 성분이 나타났다. 자외선-가시광선 분광분석 결과는 콜롬비아산 에메랄드 시료에서 열처리 후에 전체적인 흡수 세기가 증가 한 것을 확인 하였다. 적외선 분광 분석 결과, hydrothermal 합성 에메랄드에서 Cl 성분에 관련된 피크가 $3000-2600cm^{-1}$에서 나타났고, 천연 에메랄드에서는 $CO_2$에 기인하는 $2358cm^{-1}$피크가 열처리후에 감소된 것을 확인하였다. 이는 열처리 후에 기체 성분이 변화된 것과 일치 하였다.

• Carbon letters
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• 제10권4호
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• pp.325-328
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• 2009

This cycloaddition of [70]fullerene with methyl azidoacetate in benzene under ultrasonic irradiated condition afforded the closed [5,6]-bridged aziridino[70]fullerene derivative, which was unusual product of cycloaddition to the 5,6-junction of fullerene. Its structure was determined by FAB-MS, UV-vis, $^1H-$ and $^{13}C$-NMR spectral data. The closed [5,6]-bridged aziridino[70]fullerene-functionalized gold nanoparticle films were self-assembled using the layer-by-layer method on the reactive of glass slides functionalized with 3-mercaptopropyl trimethoxysilane. The functionalized glass slides were alternately soaked in the solution containing closed the [5,6]-bridged aziridino[70]fullerene and 4-aminothiophenoxide/hexanethiolate-protected gold nanoparticles. The closed [5,6]-bridged aziridino[70]fullerene-functionalized gold nanoparticle films have grown up to 5 layers depending on the immersion time. The self-assembled nanoparticle multilayer films were characterized using UV-vis spectroscopy showed that the surface plasmon band of gold at 527 nm gradually became more evident as successive layers were added to the films.

• 방사선산업학회지
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• 제10권1호
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• pp.1-5
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• 2016

In this study, the effect of high-energy proton irradiation on the optical properties of polyacrylonitrile (PAN) films was investigated. PAN thin films spin-coated on a substrate were irradiated 150 keV proton ions at various fluences. The changes in the chemical structure and optical properties were investigated by FT-IR and UV-vis spectroscopy. The results of the FT-IR analysis revealed that the cyclization reaction took place by proton irradiation and the degree of cyclization increased with an increasing fluence. Based on the UV-vis analysis, the optical band gap of PAN decreased from 2.84 to 2.52 eV with an increasing fluence due to the formation of carbon clusters by proton irradiation. In addition, the number of carbon atoms per carbon cluster and the number of carbon atoms per conjugation length were found to be increased with an increasing fluence.

• 한국염색가공학회지
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• 제21권5호
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• pp.51-57
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• 2009

Since heavy metal pollution is a significant global environmental problem and very dangerous to human health, the improved methods for detecting heavy metals are required recently. Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environment monitoring. New direct dyes having the function of colorimetric chemosensors were synthesized. When metal ions such as $Al^{3+}$, $Ca^{2+}$, $Cd^{2+}$, $Cr^{3+}$, $Cu^{2+}$, $Fe^{2+}$, $Fe^{3+}$, $Hg^{2+}$, $Li^+$, $Mg^{2+}$, $Na^+$, $Ni^{2+}$, $Pb^{2+}$ and $Zn^{2+}$ were added each solution of new direct dyes, the color of solution was changed and can be easily detected with naked eyes without expensive experimental equipment such as atomic absorption spectrometer (AAS) or inductively coupled plasma?mass spectrometer (ICP-MS). The new benzidine analogues were diazotized and reacted with couplers such as H-acid, J-acid, Chromotropic acid, Nevill-winther acid and gamma acid to synthesize new direct dyes. The structures of the new direct dyes were confirmed by high resolution mass spectrometer (FAB ionization) and evaluated with UV-Vis spectroscopy. The UV-VIS spectroscopy was measured for the dye solutions by adding various concentrations of metal ions. It was observed that the absorbance in UV-Vis spectra was changed as the heavy metal ions were added.

• 한국분말재료학회지
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• 제27권3호
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• pp.233-240
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• 2020

Nano-sized ZnSe particles are successfully synthesized in an aqueous solution at room temperature using sodium borohydride (NaBH₄) and thioglycolic acid (TGA) as the reducing agent and stabilizer, respectively. The effects of the mass ratio of the reducing agent to Se, stabilizer concentration, and stirring time on the synthesis of the ZnSe nanoparticles are evaluated. The light absorption/emission properties of the synthesized nanoparticles are characterized using ultraviolet-visible (UV-vis) spectroscopy, photoluminescence (PL) spectroscopy, and particle size analyzer (PSA) techniques. At least one mass ratio (NaBH4/Se) of the reducing agent should be added to produce ZnSe nanoparticles finer than 10 nm and to absorb UV-vis light shorter than the ZnSe bulk absorption wavelength of 460 nm. As the ratio of the reducing agent increases, the absorption wavelengths in the UV-vis curves are blue-shifted. Stirring in the atmosphere acts as a deterrent to the reduction reaction and formation of nanoparticles, but if not stirred in the atmosphere, the result is on par with synthesis in a nitrogen atmosphere. The stabilizer, TGA, has an impact on the Zn precursor synthesis. The fabricated nanoparticles exhibit excellent photo-absorption/discharge characteristics, suggesting that ZnSe nanoparticles can be alloyed without the need for organic solutions or high-temperature environments.