• 한국환경보건학회지
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• 제32권1호
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• pp.1-7
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• 2006

This study was performed to investigate airborne lead concentration and surface lead contents in preschool facilities. Arithmetic mean of indoor lead concentration in urban area was $44.7\;ng/m^3$ (Geometric mean $32.1\;ng/m^3$) whereas outdoor concentration was $39.5\;ng/m^3$ (GM $22.8\;ng/m^3$). In rural area, airborne lead concentrations were $14.2\;ng/m^3\;(GM\;7.9 ng/m^3),\;12.6\;ng/m^3\;(GM\;5.6 ng/m^3)$, respectively. There is statistical significance of the lead concentrations among the locations of preschool facilities. About $37\%$ of qualitative lead check samples was positive and mainly was found in lead based paint. Though lead concentrations on the floor and window sill were well below the US EPA and HUD standard (floor $40\;{\mu}g/ft^2\;(4.3\;{\mu}g/100\;cm^2)$, window sill $250\;{\mu}g/ft^2\;(26.9\;{\mu}g/100\;cm^2)$, respectively), there were much samples which exceed the standard, i.e., $29\%$ of surface wall, $20\%$ of the desk and chair, $100\%$ of painted wood box of tested samples. In view of our study and hazard of lead to children, we recommended that the contents of lead in preschool facilities should be lowered as possible.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.87-96
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• 2009

This study practically investigated the effects of the newly developed isolation-heat paints applied into the buildings and the roads in Japan. After 1970 since the gravitation of population toward the cities has got more deeply involved due to the development of industries, the increased paved roads and the heats come out from the industrial chimneys cause the heat island effect. The dark colored paints on the roads and the stagnations of air blocked by large buildings turned out to be also the main reasons for the heat island effect. Therefore, in order to cool down the heats accumulated in buildings and roads, the developed isolation-heat paints applied into several different regions and the decreased temperatures and heats were accurately measured and reported.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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• pp.249-257
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• 2004

Drying and curing characteristics of PCM resins using the induction heater and short-wave infrared emitter module was studied to develop a compact oven system for the high speed CCL and post-treatment equipment. Drying of the polyester resins using the induction heater and infrared heater showed that the blistering tendency of polyester resin coating increased regardless of additives and colors of resins as the heating rate and/or dry film thickness increased. The blistering of polyester resin coating layer occurred when the heating speed was over than $25^{\circ}C/sec$ for the dry film thickness of $19\~20um$, which is the typical thickness of finish coating in CCL. So did it when the heating speed was over than $40^{\circ}C/sec$ for the dry film thickness over than 10 um. The heating efficiency of paint coated steels by the infrared heating was strongly dependent on the colors of paint coating and generally increased for the dark surface and/or coating. But the faster drying of the PCM resin coatings increased the blistering tendency of coating layer. The blistering limit for the typical finish coating by the infrared heating was estimated as the heating rate slower than $20^{\circ}C/sec$ regardless of colors of PCM resins.

• Journal of Korean Society for Atmospheric Environment
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• 제21권E2호
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• pp.41-48
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• 2005

A novel hybrid system composed of a biotrickling filter and an activated sludge reactor was investigated under the conditions of four different SRTs (sludge retention times). The performance of the hybrid reactor was found to be directly comparable among the four different sludge ages. Discernible differences in the removal performance were observed among four different SRTs of 2, 4, 6, and 8 days. High removal efficiency was achieved by continuous circulation of activated sludge over the immobilized mixture culture, which allowed on pH control, addition of nutrients, and removal of paint VOCs (volatile organic compounds). The results also showed that the removal efficiency for a given pollutant depends on the activity of microorganisms based on the SRT. As the SRT increased gradually from 2 to 8 days, the average removal performance decreased. The highest removal rate was achieved at the SRT of 2 days at which the highest OUR (oxygen uptake rate), $6.1mg-O_2/liter-min$ was measured. Biological activity in the recycle microbes decreased to a much lower level, $3.6mg-O_2/liter-min$ at a SRT of 8 days. It is thus believed that young microorganisms were more active and more efficient for the VOCs removal of low concentrations and high flow rates. The apparent correlation of $R^2=0.996$ between the average removal efficiency and the average OUR at each SRTs suggests that VOCs degradation by young cells significantly affected the overall removal efficiency for the tested SRTs.

• International Journal of Concrete Structures and Materials
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• 제2권2호
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• pp.83-90
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• 2008

Permeability to vapor and water among other performances required for finishing materials is dealt with in this study. The relative moisture content of concrete coated/covered with a finishing material was experimentally investigated while changing the environmental conditions including temperature, relative humidity, and rainfall. An organic paint (water-based urethane), organic synthetic resin emulsion-type film coating (film coating E), and inorganic porcelain tiles were selected as the finishing materials. When compared from the aspect of vapor and water permeability, the vapor permeability and water permeability of water-based urethane were high and low, respectively; those of film coating E were high and high, respectively; and those of porcelain tiles were low and low, respectively. This means that the moisture state of concrete structures is governed not only by the environmental conditions but also by the performance of finishing materials. It is therefore of paramount importance to appropriately select a finishing material to address the specific deteriorative factors involved in the concrete structure to be finished.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1288-1293
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• 2009

The TES (Thermal Energy Storage) cooling system utilizing cheaper off-peak electricity has been applied just for building air-conditioning currently and causes limitation of usage rate and inefficiency of national resources utilization. In this regard, more says the necessity to apply TES system in industrial cooling system which is longer using period and wider usage. In this study, we will approve the technical and economical improvement in efficiency of industrial cooling system applied TES system by utilizing cheaper off-peak electricity and it will attribute the promotion of TES system and stabilization of supply and demand of electric power by proving the necessity to develop more efficient industrial cooling system by combining TES system.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 추계학술발표회
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• pp.35-41
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• 2007

An International Convention on the control of harmful anti-fouling system on ships(AFS Convention) was adopted on 5 October 2001 at Diplomatic Conference in London, and is expected to be presently effectuated with ratification of more than 25-member nations possessing about 25% of total world tonnage. This convention regulates the operation of harmful anti-fouling system and especially prohibits the use of organotin compounds contained in anti-fouling paint. Organotin compounds have a tendency to be easily extracted by specific solvents and have high polarity and low volatility as specific characteristics. This drives us to attempt of going through the process named derivatization that is required in analysis using a gas chromatography(GC). This study was conducted to determine the proper pre-treatment method, ethylation in comparison with hydridization on the analysis of tributyltin in organotin compounds and to verify the application of the method through the experimental analysis practically used anti-fouling paint and painted layer sample of the served ship.

• 한국식품과학회지
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• 제15권4호
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• pp.348-352
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• 1983

보리차 추출액(抽出液)의 분무건조(噴霧乾燥)를 위(爲)한 분무(噴霧) 장치(裝置)로 paint용(用) spray gun을 사용(使用)할 경우 분무(噴霧)에 중요한 영향(影響) 요소(要素)로 작용하는 보리차 추출액(抽出液)의 물성(物性)을 조사하였으며, 각(各) 농도(濃度) 및 공기(空氣) 송입(送入) 압력(壓力)에서 공기일액체(空氣一液體) 혼(混) 합비(合比)를 산출(算出)할 수 있는 식(式)을 유도하였고 paint용(用) spray gun에 의해 생성(生成)되는 미세액적(微細液滴)의 범위(範圍)를 조사하였다. 1. 보리차 추출액(抽出液)의 고형분(固形分) 함량(含量)(C, %)과 비중(比重)(${\rho}$) 및 점도(粘度)$({\mu},\;cP)$ 와의 관계(關係)는 각각 C=245($C=245({\rho}-1),\;{\mu}=e^{0.17c}$과 같았다. 2. Atomizer를 통과(通過)하는 공기(空基)의 압력(壓力)(P, mmHg)과 공기(空氣)와 액체(液體)의 무게 혼합비(混合比)$(Ma/M{\ell}$)=aP+b의 관계(關係)가 성립(成立)하였다. 이 식(式)에서 a, b는 보리차 추출액(抽出液)의 농도(濃度)에 따라 정(定)해지는 계수이다. 3. 페인트용(用) spray gun의 분무(噴霧)에 의하여 형성(形成)되는 미세액적(微細液滴)은 보리차 추출액(抽出液)의 농도(濃度)가 $3.1%{\sim}25.2%$, 공기 송입(送入) 압력(壓力)이 $164{\sim}564mmHg$인 조건하(條件下)에서 $13{\mu}m{\sim}270{\mu}m$ 크기의 범위(範圍)에 있었다.

• 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.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.287-288
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• 2003

Polyurethane(PU) materials have been generally used in the automobile, paint, furniture, adhesive, and textile industries. The use of Waterborne PU was motivated form the environmental point of view, i.e. reduction of solvent emissions into the atmosphere(volatile organic compounds, VOC)[1]. Generally speaking, phase change materials (PCM) have the capability of absorbing or releasing thermal energy to reduce or eliminate heat transfer at the temperature range of the particular temperature stabilizing material[2]. (omitted)