• 한국전기전자재료학회논문지
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• 제30권11호
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• pp.722-727
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• 2017

Transparent ZnS ceramics were synthesized by hydrothermal synthesis ($180^{\circ}C$ for 70 h), and were sintered by a hot press process at $950^{\circ}C$. To confirm the optical properties of the ZnS ceramics after sintering for various sintering holding times, we performed X-ray diffraction analysis, scanning electron microscopy, and Fourier-transform-infrared spectroscopy. The ZnS nanopowders was found to be single-phase (cubic) without any hexagonal phase. However, the hexagonal phase is formed and increases in content with increasing sintering holding time. The density of the ZnS ceramics was above 99.7%, except for the unsintered one. The ZnS ceramics showed high transmittance (~70%) when sintered for more than 2 h.

• 전기학회논문지P
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• 제64권3호
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• pp.182-186
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• 2015

We investigated that effects of annealing ambient on the characteristics of functional nano thin film synthesized on glass substrate. The functional nano thin films were annealed by using rapid thermal annealing (RTA) equipment in vacuum, oxygen and nitrogen ambient, respectively. The hardness of the functional nano thin films were measured by a standard hardness testing method (ASTM D3363) such as a H-9H, F, HB and B-6B pencil (Mitsubishi, Japan). Also, the adhesion of the functional nano thin films were measured by a standard adhesion testing method (ASTM D3359) using scotch tape (3M, Korea). The contact angle of the functional nano thin films was measured by a contact angle analyzer (Phoenix 300 Touch, S.E.O.). The optical property of functional nano thin films was measured via UV-visible spectroscopy (S-3100, Scinco).

• 센서학회지
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• 제29권5호
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• pp.360-364
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• 2020

In this study, the colorimetric sensor, polyester (PET) fabric dyed with lead (II) acetate (Pb(C₂H₃O₂)₂), was fabricated and characterized for the detection of the hydrogen sulfide (H₂S). The surface morphology of the fabric was determined using scanning electron microscope and energy-dispersive X-ray spectroscopy. The optical properties of the fabric were evaluated by measuring the variation in the blue value of an RGB sensor. The fabric showed a significant color change, high linearity (R² : 0.98256), and fast response time (< 1.0 s) when exposed to H₂S. This is because the sensor is highly porous and permeable to the gas. The fabric can not only be used as a hydrogen sulfide sensor but also be used to detect and prevent H₂S influx using sticky tape on pipelines.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.669-669
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• 2013

Hierarchical N doped TiO2 nanostructured catalyst with micro, meso and macro porosity have been synthesized by a facile self-formation route using ammonia and titanium isopropoxide precursor. The samples were calcined in different calcination temperature ranging from $300^{\circ}C$ to $800^{\circ}C$ at slow heating rate ($5^{\circ}C$/min) and designated as NHPT-300 to NHPT-800. $TiO_2$ nanostructured catalyst have been characterized by physico-chemical and spectroscopy methods to explore the structural, electronic and optical properties. UV-Vis diffuse reflectance spectra confirmed the red shift and band gap narrowing due to the doping of N species in TiO2 nanoporous catalyst. Hierarchical macro porosity with fibrous channel patterning was observed (confirmed from FESEM) and well preserved even after calcination at $800^{\circ}C$, indicating the thermal stability. BET results showed that micro and mesoporosity was lost after $500^{\circ}C$ calcination. The photocatalytic activity has been evaluated for methanol oxidation to formaldehyde in visible light. The enhanced photocatalytic activity is attributed to combined synergetic effect of N doping for visible light absorption, micro and mesoporosity for increase of effective surface area and light harvestation, and hierarchical macroporous fibrous structure for multiple reflection and effective charge transfer.

• Advances in nano research
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• 제3권3호
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• pp.123-131
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• 2015

The unintentionally doped and bismuth (Bi) doped zinc oxide (ZnO) films were prepared by spray pyrolysis at $450^{\circ}C$ with zinc acetate and bismuth nitrate precursor. The n-type conduction with concentration $6.13{\times}10^{16}cm^{-3}$ can be observed for the unintentionally doped ZnO. With the increasing of bismuth nitrate concentration in precursor, the p-type conduction can be observed. The p-type concentration $4.44{\times}10^{17}cm^{-3}$ can be achieved for the film with the Bi/Zn atomic ratio 5% in the precursor. The photoluminescence spectroscopy with HeCd laser light source was studied for films with different Bi doping. The photocatalytic activity for the unintentionally doped and Bi-doped ZnO films was studied through the photodegradation of Congo red under UV light illumination. The effects of different Bi contents on photocatalytic activity are studied and discussed. Results show that appropriate Bi doping in ZnO can increase photocatalytic activity.

• 보존과학회지
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• 제35권5호
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• pp.403-415
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• 2019

세조대왕연(충청남도 민속문화재 제14호)은 조선의 7대왕 세조(재위 1455-1468)가 마곡사에 두고 간 것으로 전해지는 가마이다. 세조대왕연의 채색에는 흑색, 백색, 황색, 적색 및 녹색 등 5가지 계열의 색상이 사용되었다. 색도 측정 결과 황색은 자황 채색부와 금칠 채색부에서 명도와 황색도의 차이가 두드러졌으며 적색은 진사로 채색된 지점에서만 적색도가 높게 측정되었다. 광학현미경 관찰, 주사전자현미경 관찰 및 성분 분석을 수행한 결과, 흑색은 먹, 백색은 백토와 연백, 황색은 자황과 합금, 적색은 연단과 주사 및 석간주, 녹색은 녹염동광을 안료로 사용하였다. 박락된 극미량 안료편의 단면을 분석한 결과, 백토와 연백의 순서로 바탕층을 올린 것이 나타났으며 이를 기초로 세조대왕연의 채색기법을 고찰하였다.

• 보존과학회지
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• 제33권2호
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• pp.61-73
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• 2017

경산 임당 유적에서 출토된 61점의 칠기유물에 대해 현미경관찰 및 FT-IR, SEM-EDX를 이용하여 당시 옻칠기법을 확인하고자 하였다. 칠기유물의 하지에는 메움제로서 토분, 그을음, 목탄 등이 이용되었으며, 붉은 칠에는 산화철(석간주)이 사용되었다. 하지층은 구성방법에 따라 5가지 방법으로 구분되었으며, 중간층과 상층은 구성방법에 따라 8가지 방법으로 구분되어, 총 17가지의 칠기법이 확인되었다. 다른 유적의 칠기법과 비교한 결과, 하지층은 동시대의 다른 유적의 칠기법과 동일한 방법이었으나, 경상 지역에서 산화철이 붉은색 안료로 주로 사용된 것을 확인 할 수 있었다.

• Journal of Astronomy and Space Sciences
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• 제26권4호
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• pp.487-498
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• 2009

지난 2005년 1월 4일 보현산 천문대(BOAO)의 BOES(BOao Echelle Spectograph)를 이용하여 Machholz(C/2004Q2) 혜성을 관측하였다. 이 논문에서는 Machholz 혜성의 고분산 분광 자료를 이용하여 미확인 분광선에 관한 연구를 수행하였으며 연구에 이용된 분광선의 파장 범위는 $4800{\sim}8100{\AA}$ 영역이다. 기존에 있던 Swift- Tuttle 혜성 Brorsen-Metcalf 혜성, Austin 혜성, 그리고 122P/de Vieo 혜성의 자료들과 비교분석을 하였다. 다수의 미확인 분광선에 대한 원인물질을 알아냈고, 이러한 자료들은 앞으로 혜성 연구에 있어서 유용한 자료로 활용될 수 있을 것이다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 춘계학술발표회 초록집
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• pp.14-14
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• 2001

Nitride films such as TiN, CrN etc. deposited on glass by PVD processes have been developed for many industrial applications. These nitride films deposited on glass were widely used for not only decorative and optical coatings but also wear and corrosion resistance coatings employed as dies and molds made of glass for the example of lens forming molds. However, the major problem of nitride coatings on glass by PVD process is non-uniform film owing to pin-hole and micro crack. It is estimated that nonuniform coating is influenced by a different surface energy between metal nitrides and glass due to binding states. In this work, therefore, for the evaluation of nucleation and growth mechanism of nitride films on glass TiN and CrN film were synthesized on glass with various nitrogen partial pressure by unbalanced magnetron sputtering. Prior to deposition, for the examination of relationship between surface energy and film microstructure plasma pre-treatment process was carried out with various argon to hydrogen flow rate and substrate bias voltage, duty cycle and frequency by using pulsed DC power supply. Surface energy owing to the different plasma pre-treatment was calculated by the measurement of wetting angle and surface conditions of glass were investigated by X-ray Photoelectron Spectroscopy(XPS) and Atomic Force Microscope(AFM). The microstructure change of nitride films on glass with increase of film thickness were analyzed by X-Ray Diffraction(XRD) and Scanning Electron Microscopy(SEM).

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.239-239
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• 2006

In the present study, we synthesized CBDA-FDA and its analogue, poly(4,4' -(9,9-fluorenyl)diphenylene pyromellitimide) (PMDA-FDA), and then investigated quantitatively the orientational distributions of the polymer chain segments in the surfaces of their films by using linearly polarized Fourier transform infrared (FTIR) spectroscopy and optical retardation analysis. We also examined the films' surface topographies using high spatial resolution atomic force microscopy (AFM). Further, rubbed films were used to assemble antiparallel and $90^{\circ}-twisted$ nematic (TN) LC cells, and the alignment behaviors, pretilt angles and anchoring energies of the LC molecules in the cells were determined. The films were found to have very interesting surface morphologies and LC alignment behaviors, which have not previously been reported. The observed LC alignments, pretilt angles and anchoring energies are discussed by taking into account the interactions of the LC molecules with the oriented polymer chain segments and the surface morphologies.