• 박물관보존과학
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• 제9권
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• pp.67-83
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• 2008

국립중앙박물관이 소장하고 있는 청연군주 출토복식(신수751 의류 일괄) 중 織金 및 金箔이 있는 복식의 보존 처리 과정을 소개하고자 한다. 금사 및 금박의 비파괴분석(X-선형광분석:XRF)을 실시한 다음 표면의 금(Au)이 열화가 진행되면서 분상화된 금층에 아교 2%용액을 도포하여 접착력을 강화하였다. 표면의 먼지와 오염물제거를 위해 진공흡입을 통한 건식세척과 분사식 습식세척을 병행하였고 손상부분을 보수하여 유물의 원형을 회복하였다.

• 한국정밀공학회지
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• 제12권10호
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• pp.78-88
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• 1995

For producing iron or steel products with good quality, the concentration of the material components should be analyzed quickly with high relability using XRF(Fluorescent X-Ray Spectrometer). Since the analysis results are much dependent upon the surface con- dition, the samples have to be prepared to have good test condition. This study presents an image processing system for inspecting the surface condition of the iron test sample. In order to use thd computer vision system, we need to develop a lighting device and image processing algorithm. For the adequate lighting device of inspection system, the indirect lighting device is contrived to cut the external light and provide uniform, stable and cold light. The image processing algorithm is aimed to reduce inspection time and to get similar analyzing results to those of the experienced operators. At first, the image processing algorithm checks whether the surface of the iron sample is ground well or not. Then, the defects; hole or dig are conted and surface condition is evaluated. In addition, the algorithm gives the reliability of the analyzing results in order to help operator's decision.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.443-448
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• 2012

Ferrocenyl chalcones (Fc-C(O)CH=CH-Ar: Fc-Ar) with mono- and di-1-naphthalenyl moieties (Fc-1Naph and Fc-d1Naph) were prepared and spectroscopically characterized. The enone bridge was in the s-cis conformation and the $\pi$-electrons on the C=C bond were further delocalized on the bridge. The naphthalenyl moiety deviates greatly from the enone-Cp plane by $26.9(1)^{\circ}$. Cyclic voltammetry measurements for Fc-1Naph exhibit one reversible cycle for the redox of the ferrocenyl moiety at a lower potential, and one irreversible oxidation peak at the higher potential region. For Fc-d1Naph, the cyclic voltammogram is more featureless. Fluorescence properties for both compounds are active in polar solvents with $\lambda_{em}$ = 500 nm (EtOH) and $\lambda_{em}$ = 512 nm (MeOH) for Fc-1Naph and $\lambda_{em}$ = 496 nm (EtOH) and $\lambda_{em}$ = 508 nm (MeOH) for Fc-d1Naph. The intensity of Fc-d1Naph is more than twice than that of Fc-1Naph. The fluorescence properties for both compounds are inactive in the less polar solvents such as $CH_3CN$, $CH_2Cl_2$ and $CHCl_3$.

• Environmental Engineering Research
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• 제18권1호
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• pp.21-28
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• 2013

In this study, the applicability of visible light-emitting-diodes (LEDs) to the photocatalytic degradation of indoor-level trichloroethylene (TCE) and perchloroethylene (PCE) over N-doped $TiO_2$ (N-$TiO_2$) was examined under a range of operational conditions. The N-$TiO_2$ photocatalyst was calcined at $650^{\circ}C$ (labeled N-650) showed the lowest degradation efficiencies for TCE and PCE, while the N-$TiO_2$ photocatalysts calcined at $350^{\circ}C$, $450^{\circ}C$, and $550^{\circ}C$ (labeled as N-350, N-450, and N-550, respectively) exhibited similar or slightly different degradation efficiencies to those of TCE and PCE. These results were supported by the X-ray diffraction patterns of N-350, N-450, N-550, and N-650. The respective average degradation efficiencies for TCE and PCE were 96% and 77% for the 8-W lamp/N-$TiO_2$ system, 32% and 20% for the violet LED/N-$TiO_2$ system, and ~0% and 4% for the blue LED/N-$TiO_2$ system. However, the normalized photocatalytic degradation efficiencies for TCE and PCE for the violet LED-irradiated N-$TiO_2$ system were higher than those from the 8-W fluorescent daylight lamp-irradiated N-$TiO_2$ system. Although the difference was not substantial, the degradation efficiencies exhibited a decreasing trend with increasing input concentrations. The degradation efficiencies for TCE and PCE decreased with increasing air flow rates. In general, the degradation efficiencies for both target compounds decreased as relative humidity increased. Consequently, it was indicated that violet LEDs can be utilized as energy-efficient light sources for the photocatalytic degradation of TCE and PCE, if operational conditions of N-$TiO_2$ photocatalytic system are optimized.

• Nano
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• 제13권12호
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• pp.1850147.1-1850147.14
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• 2018

In this work, water-soluble and blue-emitting carbon nanodots (CDs) were synthesized from apple peels for the first time via one-step hydrothermal method. The synthetic route is facile, green, economical and viable. The as-prepared CDs were characterized thoroughly by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman, Fourier transform infrared (FT-IR), X-ray photoelectron (XPS), fluorescence and UV-Vis absorption spectroscopy in terms of their morphology, surface functional groups and optical properties. The results show that these CDs possessed ultrasmall size, good dispersivity, and high tolerance to pH, ionic strength and continuous UV irradiation. Significantly, the CDs had fast and reversible response towards temperature, and the accurate linear relationship between fluorescence intensity and temperature was used to design a novel nanothermometer in a broad temperature range from 5 to $65^{\circ}C$ facilely. In addition, the fluorescence intensity of CDs was observed to be quenched immediately by Cr(VI) ions based on the inner filter effect. A low-cost Cr(VI) ions sensor was proposed employing CDs as fluorescent probe, and it displayed a wide linear range from 0.5 to $200{\mu}M$ with a detection limit of $0.73{\mu}M$. The practicability of the developed Cr(VI) sensor for real water sample assay was also validated with satisfactory recoveries.

• 한국화재소방학회논문지
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• 제14권3호
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• pp.1-5
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• 2000

본 연구에서는 옥내 조명으로 널리 사용되고 있는 형광등용 안정기의 화재위험성을 분석하였다. 안정기권선을 실체현미경으로 분석한 결과 용융흔을 다수 발견할 수 있었으나, 육안으로 원인 판정은 불가하였다. $700^{\circ}C$ 이상에서 열열화된 안정기 권선은 연신구조(elongation structure)가 없어지고 구리입자의 확대된 형태만 보였다. 단락 권선의 금속현미경 분석에서 경계면을 중심으로 주상조직 및 보이드 성장의 규칙성이 확인된 것으로 보아 전기적인 단락이 층간에 일어났음이 증명되었다. SEM을 이용한 미세구조 분석에서 용융된 부분이 확인되었다. EDX를 이용한 스펙트라 분석에서 Cu의 구성요소인 CuL 및 CuK liness 뿐만 아니라 OK line이 고르게 관측되고 있다. 이것은 재결합 과정에서 산소가 반응에 참여했음을 의미한다.

• 한국지구과학회지
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• 제26권7호
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• pp.674-682
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• 2005

충남 청양군 정산면에 위치한 삼성광산은 견운모를 생산하고 있는 광산으로서, 이 광산 및 주변지역에서 산출되는 견운모에 대한 지질학적 및 광물학적 연구를 실시하였다. 이 연구를 위해 야외지질조사 및 편광현미경 관찰, X선회절분석, 전자현미분석, X선형광분석, 시차열분석, K/Ar 동위원소분석 등의 실내연구를 실시하였다. 삼성광산 지역은 선캠브리아기의 화강편마암이 넓게 분포하고 있으며, 같은 시기의 운모편암이 발달하고 있다. 견운모는 화강편마암의 열수변질 작용에 의해 생성된 것으로 사료되며, 원암의 주요 구성광물인 정장석 $\to$사장석$\to$흑운모의 순서로 변질된다. 견운모화가 진행되어 감에 따라 석영의 외곽부분에서 용해작용에 의한 만곡현상이 심화되다가 점차 사라진다. 견운모로의 변질작용이 진행됨에 따라 모암의 화학성분은 $SiO_2\;and\;Na_2O$ 함량은 감소하는 반면, $Al_2O_3\;and\;K_2O$는 증가하는 양상을 나타낸다. 견운모의 생성시기는 중생대 쥬라기이며, 이 시기는 화강편마암을 관입한 흑운모화강암의 관입시기와 잘 일치한다.

• 한국의류학회지
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• 제37권6호
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• pp.764-771
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• 2013

The metal component of Chinese and Korean traditional gold thread was analyzed nondestructively using P-XRF and classified morphologically. In the nondestructive analysis of 22 Chinese and Korean artifacts, there were 10 gold threads made up of Au in China and 7 in Korea; in addition, there were 4 silver threads made up of Ag in Korea and 1 copper thread made up of Cu in China. In the morphological classification, 7 gilt paper strips were confirmed in China and Korea and 4 wrapped threads were identified in China and Korea. Zn, Sn and Fe (minor components of the threads) were detected. These components were assumed to be transferred from the metal found in burial goods.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1495-1500
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• 2014

Two new complexes with 5-methyl-1-(pyridine-3-yl)-1H-1,2,3-triazole-4-carboxylic acid (Hmptc) ligand: [$Cd(mptc)_2(H_2O)_4$] (1) and $[Cu(mptc)_4{\cdot}2H_2O]_n$ (2) were prepared and their crystal structures were determined by single crystal X-ray diffraction analyses. In complex 1, the Cd(II) ions coordinates with the pyridyl nitogen atom from the Hmptc ligand, forming a mononuclear Cd(II) compound. Complex 2 exhibits a novel two-dimensional (2D) polymer in which four Hmptc ligands stabilize the Cu(II) atom. And the coordination involves one nitrogen atom of the triazole, one oxygen atom of the carboxylic acid and the pyridyl nitrogen atom. In addition, FT-IR and solid-state fluorescent emission spectroscopy of two compounds have been determined.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1076-1078
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• 2004

In this paper, we report $Eu^{2+}$ activated green phosphor $Ba_2CaMgSi_2O_8:Eu^{2+}$. This phosphor absorbs ultroviolet radation and emits a green visible light. The phosphors were synthesized by conventional solid state reaction method. Reagent grade $BaCO_3$, $CaCO_3$, MgO, $SiO_2$, $Eu_2O_3$ were used as raw materials. The raw materials were mixed thoroughly with an appropriate amount of ethanol in an agate mortar and then dried at 90 $^{\circ}C$ for 2 hours. The mixture was sintered at 900 $^{\circ}C$ for 2 hours and reheated at the mild reducing atmosphere 5% $H_2$ gas mixed with 95% $N_2$ gas at about 900 $^{\circ}C$ to 1250 $^{\circ}C$ for 2 hours. The photoluminescence spectra of the phosphor powders were measured by a fluorescent spectrophotometer. The crystal structure of phosphor powders were investigated by X-ray diffractometer.