• 한국염색가공학회지
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• 제34권2호
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• pp.127-133
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• 2022

With the increasing interest in the expression of individuality and appearance of modern people, it is time to conduct research and development of novel hair coloring from various angles. Therefore, taking into account the order of discoloration of hair pigments, we selected a creative and novel emulsion as a novel material for hair coloring, rather than a cosmetic material such as hot water extract using natural products dealt with in previous studies, commercially available hair manicure, and oxidation hair dye for hair. Thus, the change in tensile strength and elongation of hair samples by color was studied. As a result of the study, hair with green emulsion paint had a significantly higher maximum load, maximum stress, maximum elongation and breaking load, breaking stress, breaking elongation values are shown. Maximum in terms of modulus, green emulsion applied hair and the control group were higher in the 0-15s strain and 15-145s sections, respectively, and the tangential modulus value was much higher in the control group than the experimental group hairs in all the 0-145s sections. This study, which analyzes the dynamic changes of hair samples that extend the daily color gamut, will greatly contribute to the development of innovative hair coloring materials in the research and production of hair beauty works, and it is judged that it will also contribute to the development of the beauty industry.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.19-20
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• 2021

In order to reduce the emission of harmful substances that degrade indoor air quality, the Ministry of Environment strengthened the standards for the content of VOCs in paints to supply and sell eco-friendly paints. In this related study, an eco-friendly paint mixed with a powder-type absorbent material was prepared and its characteristics were reviewed. As the amount of powder-type absorbent material increased, the workability (viscosity, peeling, etc) decreased. Accordingly, this study aims to examine which particle size is suitable according to the particle size of the granular adsorbent while improving the problem of the powdery adsorbent by using the granular adsorbent. As an experimental plan, the particle size of granular activated clay is selected to be 0.250, 0.425, 0.710(mm), and the decrease rate of VOCs concentration and impact resistance are reviewed. As a result of the experiment, as the particle size of the granular activated clay increased, the decrease rate of the VOCs concentration increased and the impact resistance improved. Therefore, considering the problems that occur after actual painting, the particle size of granular activated clay of 0.425mm is suitable.

• 한국해양학회지:바다
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• 제3권4호
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• pp.249-260
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• 1998

해수에 잠긴 인공기질 표면에서 미세조류의 부착과 후속적으로 나타나는 성장과정을 이해하기 위해 규조류의 부착과 주변수의 종 급원(species pool)과의 관계를 조사하였다. 1995년 7월부터 1997년 2월까지 인천항 내에서 아크릴 슬라이드를 이용하여 규조류의 부착에 관해 연구하였고, 주변 해수를 조사하였다. 또한 생물막 초기형성 과정에서 노출시간의 증가에 따라 나타나는 부착미세조류 군집의 종조성과 수도의 변화를 유리, 아크릴, 티타늄, 구리 및 생물오손방지 페인트로 도포된 슬라이드 등 다양한 인공기질 표면을 이용하여 조사하였다. 아크릴 슬라이드에서 규조류의 이입률은 주변수의 저서규조류의 수도변화와 유의성 있는 상관관계를 나타냈으며 ($r^2$=0.78, p<0.01, n=42), 이는 주변수의 저서규조류의 수도에 의해 영향을 받는 것을 지시한다. 아크릴 슬라이드에서 봄철에 단배선 형태 규조류의 부착능력(이입계수)이 복배선 형태에 비해 5 배 높게 나타났다. 그러나 부착점유율은 단배선 형태가 복배선 형태에 비해 3 배 낮게 나타났다. 겨울철에는 중심형 규조류의 부착능력이 다른 형태들에 비해 높게 나타났고 부착점유율도 높게 나타났다. 이는 규조류의 부착이 주변해수에 출현한 저서 규조류의 수도 및 부착능력에 의한 결과임을 지시한다. 우상형 규조류가 연구기간동안 모든 인공기질 표면에 대부분 부착 출현하였고, 겨울철에는 중심형 규조류가 모든 인공기질 표면에 우정 부착하였다. 생물오손방지 페인트로 처리된 표면에서는 독성에 대한 내성이 강한 것으로 판단되는 Hantzschia virgata, Licmophora abbreviata, Melosira nummuloides가 우점하여 부착하였다. 노출시간이 증가함에 따라 부착규조류의 수도는 유리, 티타늄, 아크릴 슬라이드에서 지수적으로 증가하였고, 최대수도는 유리 ${\geq}$ 아크릴 > 티타늄 > 구리 ${\geq}$ 페인트처리 슬라이드의 순으로 높게 나타났다. 모든 인공기질 표면에서 부착규조류의 성장률은 $2{\sim}3^{\circ}C$에서 보다 $24{\sim}25^{\circ}C$의 수온에서 높게 나타났고, 유리 슬라이드에서 다른 표면에 비해 전반적으로 높은 값을 보였다. 해수 중에서 노출시간의 증가에 따라 관찰된 우점종은 납작한 형태인 Amphora coffeaeformis, 부채꼴 형태인 Synedra tabulata, stalk 형태인 Licmophora paradoxa 그리고 사슬형태인 M. nummuloides로 나타났고, 부착미세조류 군집에서 미소천이(micro-succession)가 관찰되었다. 이러한 우점종 조성은 미세조류 생물막이 발달하여 서식공간이 제한됨에 따라 나타난 종 적응의 결과로 보인다.

• Korean Chemical Engineering Research
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• 제60권4호
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• pp.594-605
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• 2022

마이크로웨이브 소성로를 이용하여 굴 패각을 소성하여 CaO 제조하였다. 제조된 CaO를 수화 반응시켜서 Ca(OH)₂를 분석하였다. 합성한 Ca(OH)₂를 주성분으로하여 외부용 수성 도료 배합하였다. 굴 패각(325 mesh, 43 ㎛)은 (a) 950 ℃/1 시간와 (b) 1,150 ℃/1 시간 동안 탈탄산화반응을 시켜 CaO를 제조하였다. (a)의 소성 조건에서는 CaO 56.7 wt%이고 (b)의 소성 조건에서는 CaO 100 wt%였다. 굴 패각의 소성에 의한 CaO를 석회석의 경우와 비교하기 위하여 석회석(25~30 mm)을 950 ℃/1 시간 동안 탈탄산화 반응시켜서 CaO를 제조하였으며, XRD 분석 결과 CaO 100 wt%로 분석 되었다. 굴 패각의 소성 조건인 (b) 1,150 ℃, 1시간으로 CaO를 제조하여 수화 반응을 통하여 Ca(OH)₂를 합성하였다. 제조된 CaO의 수화 조건은 (a) CaO : H₂O(100 g : 200 g)과 (b) CaO : H₂O(100 g : 400 g)로 수화 반응성을 실시하였다. 수화 반응 결과, 저 반응성으로 확인 되었다. 100 wt%의 Ca(OH)₂를 합성하였다. 특히 (a)의 수화 조건에서 합성한 Ca(OH)₂는 판상형으로 분석되었다. 굴 패각으로 합성한 Ca(OH)₂를 주성분으로 외부용 수성 도료를 배합하였다. 외부용 수성 도료 표준 규격(KS M 6010)의 15개 항목에 대하여 분석하였을 때 냉동안정성을 제외한 다른 모든 기준에 적합한 것을 확인하였다.

• 청정기술
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• 제10권2호
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• pp.89-100
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• 2004

도장부스 수조 내에 부유되는 도장 슬러지의 효율적인 분리를 위한 수조 형상 및 skimmer 설치에 대한 설계를 최적화하였다. VOF 모델을 사용하여 수조 내 도장 슬러지-물-공기 혼합물의 유동형태에 대한 해석을 수행하였고, 해석된 결과를 바탕으로, 수조 내 물로부터 효과적인 슬러지 분리를 위한 도장 부스 수조 내 흡입관, 격판 및 슬러지 유입구의 설치에 대한 최적 설계 기준을 제시하였다. 더 나아가, skimmer 가 수조 내 물에 잠기는 설치조건에 대한 최적화를 통하여 슬러지 흡입 시 공기 혼입 및 압력손실을 최소화 하였다.

• Environmental Analysis Health and Toxicology
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• 제18권1호
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• pp.63-67
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• 2003

Benzoic acid is produced about 700 tons/year in Korea as of 1998 survey. Most is used as a stabilizer in the processes of synthesis of pharmaceuticals and dyes. It is also used for ingradient of paint, disinfections, and antifungals. Due to the antioxidant activity of benzoic acid, the chemical is also used as food preservatives. Although the chemical is widely used in Korea, exposure levels in air, water, soil or sediment have not been monitored or estimated so that risk evaluation of benzoic acid was not possible. In this study, distribution of the chemical among environmental media was estimated using EQC model based on the chemical-physical properties. In Level I and II of which the chemical are hypothesized in equilibrium and no transfer through the media, more than 93％ of benzoic acid are estimated to be distributed in water. However, in Level III of which non-equilibrium and intermedia transfer could be occurred, the chemical is estimated to distributed to soil, 64％ and water,35% as of total amount.

• 한국농촌건축학회논문집
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• 제17권2호
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• pp.9-16
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• 2015

This study comparatively analyzed thermal characteristics of the green color, which is currently used the most, and other various colors of a rooftop urethane water proofing sheet. This study also analyzed the cooling performance by color of the water proofing sheet that fused cooling paints, and presented the effective water proofing sheet color for building energy savings. The experimental results are as follows: (1) The value of L (brightness) diminished, and brilliance also became lower from the white color to the black color, and thus, it was confirmed that relatively more heat was absorbed. In a and b chromaticity, which is the color attribute that ignores brightness, no special relationship was identified. (2) Considering that the cooling performance effect is bigger in summer than winter, due to heat reflection, the white water proofing sheet is more effective in building energy savings than the green water proofing sheet that is currently used the most. (3) The water proofing sheet's color has an impact more on cooling performance than the color of the background side of a structure on which water proofing sheet is installed. The experiment object of gray, of which background side is similar to cement mortar, was lower by $5.7^{\circ}C$ than the white background side.

• 한국표면공학회지
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• 제51권2호
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• pp.95-103
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• 2018

Recently, many types of constructional steels have been often exposed to under severe corrosive environments due to acid rain with increasing environmental contamination. In order to inhibit their corrosion in severe corrosive environments, a painting method has been widely applied to numerous constructional steels of land as well as marine. Therefore, development of paint having a good quality of corrosion resistance is considered to be very important. In this study, four types of anti-corrosive paints (AP: Phenol epoxy, AC: Ceramic epoxy, AT: Coal tar epoxy, AH: High solid epoxy) were coated to the specimens, and then, were immerged in various salt solutions (0.1, 0.3, 3, 6, 9 and 15% NaCl solutions) for 11 days. And, the corrosion resistance of these samples by effect of osmotic pressure with salt concentration was investigated with electrochemical methods such as measurement of corrosion potential, impedance and corrosion current density. The corrosion current densities of all samples (AC, AT and AH) submerged in 3% NaCl solution exhibited the smallest values compared to other salt solutions. However, in the case of lower values of salt solutions than 3% NaCl solution, the corrosion current density increased again because it makes easier for water, dissolved oxygen and chloride ion etc. to invade toward inner side of coating film due to increasing of the osmotic pressure than 3% NaCl solution, but in the case of higher values of salt solutions than 3% NaCl solution, the coating film is easily deteriorated due to high concentration of chloride ion rather than the osmotic pressure, which resulted in increasing the corrosion current density. In particular, the AC sample indicated the best corrosion resistance in 6% NaCl solution compared to other samples. Consequently, it is considered that the corrosion mechanism of the coated steel plate is completely different from bare steel plate, and the corrosion resistance of coating film by osmotic pressure and chloride ion depend on various types of epoxy of paint in NaCl solution.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.801-807
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• 2021

전기 전자 부품을 기반으로 하는 통신장비, 컴퓨터, 이동 수단, 전산망, 군사용 장비 등 여러 산업 분야 및 사회기반시설에 있어 전자파 차폐의 필요성이 커지고 있다. 구조물의 전자파 차폐 방법은 차폐 콘크리트, 차폐 문, 차폐 창문과 같이 차폐성능을 가지고 있는 자재를 사용하여 시공하는 방법, 그리고 차폐성능이 없는 재료에 차폐 도료를 코팅하는 방법이 있다. 전자파 차폐 도료는 탄소나노튜브, 흑연, 카본 블랙, 탄소 섬유와 같은 전도성 물질을 사용하여 만들어지며, 일반적으로 사용되고 있는 수성도료에서 전자파 차폐 성능이 추가된 도료이다. 이 연구에서는 전자파 차폐 무기계 도료를 개발하기 위한 목적으로 전도성 흑연, 카본 블랙을 차폐원료로 사용한 도료의 차폐성능 및 부착성능을 평가하였다. 차폐 재료의 종류 및 사용량을 달리한 6개 배합에 대해 차폐성능과 부착강도를 평가하였다. 실험 결과, 전도성 흑연과 카본 블랙을 무게비 1:0.2로 혼합한 배합이 33.6 dB로 차폐성능이 가장 좋은 것으로 확인되었고, 부착성능은 전도성 흑연만 사용한 배합이 1.06 MPa로 가장 높은 것으로 확인되었다.

• Safety and Health at Work
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• 제7권1호
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• pp.63-71
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• 2016

Background: Construction painters have not been studied well in terms of their hazards exposure. The objective of this study was to evaluate the exposure levels of total volatile organic compounds (TVOCs) for painters in the construction industry. Methods: Activity-specific personal air samplings were carried out in three waterproofing activities [polyurethane (PU), asphalt, and cement mortar] and three painting activities (epoxy, oil based, and water based) by using organic-vapor-monitor passive-sampling devices. Gas chromatograph with flame ionization detector could be used for identifying and quantifying individual organic chemicals. The levels of TVOCs, by summing up 15 targeted substances, were expressed in exposure-index (EI) values. Results: As arithmetic means in the order of concentration levels, the EIs of TVOCs in waterproofing works were 10.77, 2.42, 1.78, 1.68, 0.47, 0.07, and none detected (ND) for indoor PU-primer task, outdoor PU-primer task, outdoor PU-resin task, indoor PU-resin task, asphalt-primer task, asphalt-adhesive task, and cement-mortar task, respectively. The highest EI for painting works was 5.61 for indoor epoxyprimer task, followed by indoor epoxy-resin task (2.03), outdoor oil-based-spray-paint task (1.65), outdoor water-based-paint task (0.66), and indoor oil-based-paint task (0.15). Assuming that the operations were carried out continuously for 8 hours without breaks and by using the arithmetic means of EIs for each of the 12 tasks in this study, 58.3% (7 out of 12) exceeded the exposure limit of 100% (EI > 1.0), while 8.3% (1 out of 12) was in 50e100% of exposure limit (0.5 > EI > 1.0), and 4 tasks out of 12 were located in less than 50% of the limit range (EI < 0.5). Conclusion: From this study, we recognized that construction painters are exposed to various solvents, including carcinogens and reproductive toxins, and the levels of TVOC concentration in many of the painting tasks exceeded the exposure limits. Construction workers need to be protected from chemical agents during their painting works by using personal protective devices and/or work practice measures. Additional studies should focus on the exposure assessment of other hazards for construction workers, in order to identify high-risk tasks and to improve hazardous work environments.