• 한국미생물·생명공학회지
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• 제30권1호
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• pp.86-90
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• 2002

포항제철소에서 사용하는 살균제와 공장냉각수를 사용하여 실험실에서 생물막 형성과 금속부식에 대한 연구를 수행하였다. 부유성 미생물은 biocide (NaOCl, 0.2％ w/v)을 첨가하면 1.5 시간 내에 모두 사멸하였으나, 생물막에 있는 고착성 미생물은 일주일이 지나도 사멸이 되지 않았다. 생물막 형성은 공장냉각수를 고온고압으로 멸균하거나, biocide(NaOCl)를 첨가하였을 경우에는 주황색의 생물막이 형성되었으나, 공장냉각수를 그대로 사용하였을 경우에는 SRB 활성에 의한 흑색(FeS)의 생물막이 형성되었다. 흑색의 생물막이 형성된 곳에서의 금속부식 속도는 주황색의 생물막이 형성된 곳의 금속부식 속도보다 2.3배 더 빨리 진행되었다.

• 수산해양기술연구
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• 제42권4호
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• pp.228-233
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• 2006

The transmittance properties of fishing lamp of the squid jigging vessel was investigated during nighttime operations in the Northwest Pacific on 21 and 29 September 2005. The metal halide lamps of white color($2.0kW{\times}168$) in the air and metal halide lamp of white color($10.0kW{\times}1$) in the underwater were used as a fishing lamp for gathering squids. The relative irradiance of metal halide lamp in the air showed peak in 850nm of wave length. The relationship between underwater illuminance(Y) and water depth(X) of metal halide lamp light in the observation areas is represented, $Y=84.137e^{-0.1105X},\;R^2=0.9974$. The distribution of underwater illuminance of measure points St. 1-5 showed low value of 0.11x in 80m depth.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제31회 춘계학술대회
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• pp.54-61
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• 2000

A method and results of classification of 4 types metallic wear debris were presented by using their color features. The color image of wear debris was used (or the initial data, and the color properties of the debris were specified by HSI color model. Particle was characterized by a set of statistical features derived from the distribution of HSI color model components. The initial feature set was optimized by a principal component analysis, and multidimensional scaling procedure was used for the definition of classification plane. It was found that five features, which include mean values of H and S, median S, skewness of distribution of S and I, allow to distinguish copper based alloys, red and dark iron oxides and steel particles. In this work, a method of probabilistic decision-making of class label assignment was proposed, which was based on the analysis of debris-coordinates distribution in the classification plane. The obtained results demonstrated a good availability for the automated wear particle analysis.

• The Journal of Advanced Prosthodontics
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• 제6권4호
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• pp.309-316
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• 2014

PURPOSE. The color of the ceramic restorations is affected by various factors such as brand, thickness of the layered the ceramic, condensation techniques, smoothness of surface, number of firings, firing temperature and thickness of dentin. The aim of this study was to evaluate the color change and surface roughness in dental porcelain with different thicknesses during repeated firings. MATERIALS AND METHODS. Disc-shaped (N=21) metal-ceramic samples (IPS Classic; Ivoclar Vivadent; Shaar, Liechtenstein) with different thickness were exposed to repeated firings. Color measurement of the samples was made using a colorimeter and profilometer was used to determine surface roughness. ANOVA and Tukey tests with repeated measurements were used for statistical analysis. RESULTS. The total thickness of the ceramics which is less than 2 mm significantly have detrimental effect on the surface properties and color of porcelains during firings (P<.05). CONCLUSION. Repeated firings have effects on the color change and surface roughness of the dental ceramics and should be avoided.

• 청정기술
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• 제15권2호
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• pp.91-101
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• 2009

아마이드계 섬유를 고농도로 염색할 때 피염물의 우수한 견뢰도를 얻기 위해 사용되는 금속착염(metal complex) 염료의 대부분은 Cr을 함유하고 있는 유독성 염료이어서, 잔욕에 남게 등의 환경적인 문제를 일으킬 뿐 아니라, $Cr^{6+}$를 함유할 경우 인체에도 심각한 질병을 줄 수 있다. 본 연구에서는 이러한 금속착염 염료를 대체하기 위해 중금속 함유량을 최소화한 반응성 염료를 양모와 나일론 염색에 응용하였다. 각 섬유에 대한 반응성 염료의 염색성을 파악하고, 실제 염색공장에서의 적용을 위해 색상 영역별 흡진률과 견뢰도 수준을 확인하였다. 또한 반응성 염료들에 대한 중금속 함량 및 유해아민분석을 통하여 그 유해성 경향을 수치적으로 검증하며, 기존 사용 염료와의 비교를 통해 미래 지향적인 청정염료로서의 가능성을 보고자 하였다.

• 한국의류산업학회지
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• 제5권3호
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• pp.283-288
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• 2003

Large quantity of metal mordant in natural dyeing has been used. For environmental reason, there is a need to reduce the amount of metal mordant and suggest the optimum amount of metal mordant in dyeing process. In this study, the relationship between mordant concentration and dyeing property was investigated. Various metal mordant concentrations of AI, Cu, Fe, Sn, were studied (from 1 to 5%). After treatment of mordant on cotton fabric, the concentration of metal ion in used mordant solution was quantified. There was no significant difference of the tone of color in mordant concentration from 1% to 5%, Therefore, there is no need to increase mordant concentration over 1%. chitosan treated cotton fabric showed a significant increase in dyeing affinity compared to untreated cotton fabric (the value of ${\Delta}E$ was 20). chitosan increased dye affinity significantly in the presence of mordant. It can be suggested that chitosan itself can replace metal mordants in the future.

• 한국물환경학회지
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• 제22권6호
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• pp.996-1003
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• 2006

The absorption characteristics of powdered activated carbon doped by transition-metal nanoparticles were investigated to enhance the remove efficiencies of $TCOD_{Mn}$ and Color from the flexo-inks wastewater. According to the adsorption dynamics of PAC and MPAC, the optimal dosage of activated-carbon adsorbents was 3 g/L under the reaction conditions of pH6.0, 30 mill of reaction time, 240 rpm of mixing intensity. The removal efficiencies by the optimal dosages were maximized as 19% $TCOD_{Mn}$, 57% Color for PAC and 88% $TCOD_{Mn}$, 95% Color for MPAC. Freundlich indexes of isotherm absorption were estimated as follows: i) For PAC, k=-8.11, 1/n=2.98, r=0.91 in the raw water, and k=0.14, b/n=0.75, r=0.96 in the biological treatment water, ii) For MPAC, k=2.69, 1/n=0.21, r=0.80 in the raw water, and k=0.74, 1/n=1.17, r=0.95 in the biological treatment water. MPAC (Powdered activated carbon doped by transition-metal nanoaprticles) was very effective in the removal of organics from the raw water and biological treatment water, as Freundlich indexes of 1/n for both types of water were estimated less than 2.0.

• 대한치과기공학회지
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• 제3권1호
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• pp.21-24
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• 1981

• 한국전기전자재료학회논문지
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• 제35권6호
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• pp.547-555
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• 2022

Color conversion layer refers to a layer that converts the blue light emitted from the backlight into the red and green light. Heavy metal-free quantum dots and perovskite nanocrystals have attracted great attention as base materials for color conversion layers due to their outstanding optical characteristics. Here, we review recent advances in the development of color conversion layers based on quantum dots. First, we overview the representative optical characteristics of quantum dots and perovskite nanocrystals, and then introduce printing techniques for color converting layers including photolithography, inkjet printing, and nanoimprinting. Finally, we conclude this review with a brief perspective.

• 한국의류산업학회지
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• 제8권3호
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• pp.343-348
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• 2006

This study aims to attain gray tone dyed goods by using tannin that is contained in green tea. Tannin is given general name of polyphenol, which has a characteristic that bonds with protein and it is used for food preservative that protects against bacteria, as well as its purpose of black tone dye for silk treatment that has been processed since its early ages. In particular, as tannin reacts with all kinds of metallic mordant and changes to various colors, when tannin acid is combined with iron, it becomes tannin steel and produces gray tone color. Tannin that is contained in green tea is condensed tannins and its structure does not hydrolyze, thus having flavan type structure. In order to find the suitable condition for processing tannin, UV-Vis part absorption spectrum of green tea tannin, dye ability based on temperature and time, reflection rate based on concentration, color changes based on acid treatment and alkali treatment, changes on surface based on concentration or metal mordant condition, and lightfastness were measured. Maximum absorption wavelength (${\lambda}_{max}$) of green tea tannin was at around 273nm, while strong absorption was also observed at below 350 nm. Dye ability of green tea tannin is done more easily on silk rather than cellulose fibers such as cotton, while the optimum condition for dyeing was observed to be at $60^{\circ}C$, for 20 minutes. As a result of acid treatment, the color of dye material consisted highly of gray tones and showed overall gray tone with the combined color of yellow and red after the alkali treatment. While it was observed that as dye concentration and metal mordant concentration increased, the color changed at counter-clockwise direction on the Y-scale of Munsell's scale of colors. Additionally, lightfastness was more on a normal fading.