• 보존과학연구
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• s.28
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• pp.91-104
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• 2007

The goal of this study was to provide basic data for arrangement of management in museum environment. We investigated characteristics of distribution on indoor air pollutants at exhibition halls and storages in museums between July and August, 2007. The monitoring carried out at three cultural sites, Pusan, Daejeon and Kyungjoo which is possessed their own exhibition hall and storage in Museums. We adopt the several pollutants for this survey such as $PM_{10}$, $PM_{2.5}$ $CO_2$, Formaldehyde, TBC, CO, $NO_2$, Rn, VOCs, $O_3$ and followed the standard method of Ministry of Environment, Korea for sampling and analysis, respectively. The results of this survey revealed that average concentration of $PM_{10}$ and $PM_{2.5}$ in storages were $117.3{\mu}g/m^3$ and $92.6{\mu}g/m^3$, respectively. The average concentration in storages of gases pollutants and microorganism such as $CO_2$, Formaldehyde, $NO_2$, Rn, TVOC, $O_3$, and TBC showed as: 788.8ppm, $30.7{\mu}g/m^3$, 0.4ppm, 6.4ppb, $1.3pCi/{\ell}$, $1,374.9{\mu}g/m^3$, 2.4ppb, and $119.4cfu/m^3$, respectively. In addition, average concentration of $PM_{10}$ and $PM_{2.5}$ in exhibition halls were $49.5{\mu}g/m^3$ and $56.1{\mu}g/m^3$, respectively. The average concentration in exhibition halls of gases pollutants and microorganism such as $CO_2$, Formaldehyde, $NO_2$, Rn, TVOC, $O_3$, and TBC showed as: 475.2ppm, $94.1{\mu}g/m^3$, 0.3ppm, 12.4ppb, $0.3pCi/{\ell}$, $1,179.1{\mu}g/m^3$, 5.2ppb, 2.4ppb, and $24.8cfu/m^3$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.199-203
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• 2003

In this study plastic optical fibers (POFs) were considered as light-transmitting media and substrates for the potential use in photocatalytic environmental purification system. After the characteristics of POFs in terms of light transmittance and absorption were determined at the beginning, the further investigation was performed through the photocatalytic degradation of trichloroethylene (TCE), iso-propanol and etc. with TiO$_2$-coated optical fiber reactor systems (POFR). It is concluded that the use of POFs is preferred to quartz optical fibers (QOFs) since the advantages such as ease of handling, lower cost, relatively reasonable light attenuation at the wavelength of near 400nm can be obtained. Various geometrical reactor shapes have been constructed and applied for the last one and half years. For the use of POF in water phase treatment, however, more detailed scientific and engineering aspects should be envisaged. This case requires a suitable mixture to obtain more stable and innocuous immobilization of photocatalyst on POF. To overcome this disadvantage, metal-organic chemical vapor deposition (MOCVD) was conducted in a fluidized bed to deposit thin films of titania on glass and alumina beads. Those can be used as photocatalysis for the removal of pollutants especially in liquid phases.

• Asian Journal of Atmospheric Environment
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• v.5 no.2
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• pp.113-120
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• 2011

Adsorbent combination studies have been carried out to remove nitrogen dioxide ($NO_2$) and volatile organic compounds (VOCs: BTEX) out of a subway environment characterized by high flow and low concentration. Optimal conditions for the high removal efficiency of the concerned target compounds were obtained through testing a series of control factors such as adsorbent sorts, thicknesses, and superficial velocity. It was found that the efficiencies increased as the specific surface area of activated carbon and its thickness increased, and external void fraction decreased. Furthermore, mixed activated carbon with granular and constructed contents was extensively tested to reduce pressure drop through the carbon bed. It was found that the performance of higher contents of granular activated carbon was better than that of higher contents of the constructed carbon. When the mixed carbon was applied to the subway ventilation system in order to eliminate $NO_2$ and VOC simultaneously, the removal efficiencies were found to be 75% and 85%, respectively.

• Journal of ILASS-Korea
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• v.18 no.2
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• pp.106-111
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• 2013

Adulterations fuel have been using in the vehicle in these days. Because gasoline, diesel prices are rising every day. so people find more cheap price fuel. Adulterations fuel caused a serious air pollution problems. Adulteration fuel were made from waste engine oil, waste paint. According to Government regulations permit to be used recycle fuel(adulteration fuel) only in industrial boiler. Unburned fuel pollutants are effected to human health. In this paper, the hazardous air pollutants characteristics in the diesel vehicles according to adulterations of vehicle fuels were carried out in the NEDC test mode in chassis dynamometer. It is revealed that the all of the regulation pollutants (THC, NOx, CO and PM) emission in the adulterations of vehicle fuels was increased also the green house gas, $CO_2$ was increased. In the hazardous air pollutants characteristics, the VOCs(Volitile Organic Compounds) BTEX(Benzene, Toluene, Ethylbenzene, Xylene) emissions in the adulterations of vehicle fuels showed higher level than these in the diesel fuels.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.4
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• pp.547-554
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• 2002

We are facing the serious environmental pollution difficulties such as acid rain, green house effects, etc. The gaseous matter NOx, SOx, VOCs which are regarded as main factors for these current pollutions are mainly emitted from power plants and vehicles. Therefore several leading countries are regulating the emissions strictly, especially the exhaust emissions from a Diesel engine without an aftertreatment device. The objective of this study is to find out soot and NO removal characteristics focused on the emissions of a Diesel engine by using nonthermal plasma for each engine speeds and loads. Electrostatic precipitator(wire-to-plate type reactor) is used for soot removal. Radicals generated from outer air and put into a mixing chamber in the end of exhaust line are used for NO removal. Concentration of exhaust emissions is analyzed from the gas analyzer(KaneMay) and FTIR to estimate by-products.

• Journal of Sensor Science and Technology
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• v.13 no.1
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• pp.41-46
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• 2004

There is currently much interest in the development of instruments that emulate the senses of humans. Increasingly, there is demand for mimicking the human sense of smell, which is a sophisticated chemosensory system. An electronic nose system is applicable to a large area of industries including environmental monitoring. We have designed a protable electronic nose system using an array of commercial chemical gas sensors for recognizing and analyzing the various odours. In this paper, we have implemented a portable electronic nose system using an array of gas sensors for recognizing and analyzing VOCs (Volatile Organic Compounds) in the field. The accuracy of a portable electronic nose system may be lower than an instrument such as GC/MS (Gas Chromatography/Mass Spectrometer). However, a portable electronic nose system could be used on the field and showed fast response to pollutants in the field. Several different algorithms for odours recognition were used such as BP (Back-Propagation) or LM-BP (Levenberq-Marquardt Back-Propagation). We applied RBF (Radial Basis Function) Network for recognition and quantifying of odours, which has simpler and faster compared to the previously used algorithms such as BP and LM-BP.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1527-1532
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• 2013

The kinetics of photocatalytic degradation of gaseous acetaldehyde and methylethylketone(MEK) were studied by the batch scale of photo-reactor. Variable parameters were initial concentration of acetaldehyde and MEK, water vapor content, and temperature. The photocatalytic degradation rate was increased with increasing concentration of acetaldehyde and MEK, but maintained gentle increase beyond a certain concentration. The Langmuir-Hinselwood model was successfully applied to correlate experimental data. Water vapor inhibited the degradation reaction of acetaldehyde and MEK. The optimum reaction temperature was $45^{\circ}C$ for acetaldehyde and MEK.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.52-59
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• 2012

Objectives: The purpose of this study was to evaluate the exposure possibility of by-products during the semiconductor manufacturing processes. Methods: The authors investigated types of chemicals generated during semiconductor manufacturing processes by the qualitative experiment on generation of by-products at the laboratory and a literature survey. Results: By-products due to decomposition of photoresist by UV-light during the photo-lithography process, ionization of arsine during the ion implant process, and inter-reactions of chemicals used at diffusion and deposition processes can be generated in wafer fabrication line. Volatile organic compounds (VOCs) such as benzene and formaldehyde can be generated during the mold process due to decomposition of epoxy molding compound and mold cleaner in semiconductor chip assembly line. Conclusions: Various types of by-products can be generated during the semiconductor manufacturing processes. Therefore, by-products carcinogen such as benzene, formaldehyde, and arsenic as well as chemical substances used during the semiconductor manufacturing processes should be controlled carefully.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.187-191
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• 2003

In this study, biomonitoring methods were developed to measure BTEXs exposure level in the air, metabolites of benzene and toluene in human urine, individual susceptibility markers in human blood for evaluation of the health effects about environmental pollution. We have also performed a small-scaled molecular epidemiology study on residents in Chuncheon and workers in workplace for these method applications. The workers in workplace were surveyed as study areas, and the residents in Chuncheon which is in the suburban area were surveyed as comparative areas in this study. Actually, 31 workers in as target group and 33 residences in as control group this epidemiological study. The results obtained from this study were as follows: 1. Benzene is a well-known carcinogen, it's median concentrations were 0.00024∼0.02057ppm at suburban area and 0.002∼00.654ppm at work place, These benzene concentrations were not exceed the OSHA(Occupational Safety and Health Administration) threshold benzene level of 1ppm in the states. 2. Metabolites product of benzene(t,t-Muconic Acid) and toluene(Hippuric Acid) were not significant both in suburban and workplace area. The median concentration of t,t-MA and HA were 0.0122, 1.44277g/g creatinine, respectively. 3. In the case of individual susceptibility markers as CYPlAl, 41.8% of them has homozygous wild type(W) and who has heterozygous variant type(H) was 35.4% and 22.8% of homozygous variant type(M) genetic type. In the case of CYP2E1, 62.82% of them has homozygous wild type(D) type, 34.62% of each has heterozygous variant type (DC) and 2.56% of them has homozygous variant type (CC). Who doesn't have GSTM1 gene was 46.25% and who has GSTM1 gene was 53.75％. Who doesn't have GSTT1 gene was 40.0％ in study groups and who has GSTT1 gene was 60.0%. Who has W genetic type, which is homozygous wild type of GSTP1, was 69.18% and H genetic type, which is heterozygous variant type was 28.4%. M genetic type which is homozygous variant type was 2.4%. 4. Concentration differences of metabolites such as t,t-MA and HA in urine, which is generated by individual susceptibility marker of GSTM1, GSTT1, GSTP1 gene of Phase I and CYP1A1, CYP2E1 gene of Phase II, was examined. As a result, GSTP1 and GSTM1 indicate slight differences depend on the amount of metabolites in urine, it was not statistically significant.

• Analytical Science and Technology
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• v.18 no.6
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• pp.542-551
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• 2005

This study is to investigate the characteristics of emission concentration according to wallpaper sort and emission time using small chamber method. The target compounds included 45 VOCs and formaldehyde, which were respectively determined by adsorption sampling and thermal desorption coupled with GC/MS method, and by sampling in DNPH cartridge and HPLC method. The emission factor of TVOC and HCHO was detected to $1.1mg/m^2{\cdot}h$ and $0.01mg/m^2{\cdot}h$ respectively, and the wallpapers of 25 satisfied emission standard. TVOC emission factor appeared in order of the concentration of PVC, natural, and Non-PVC wallpaper, while HCHO was detected very low concentration without relation to wallpaper sort. The paraffin hydrocarbons appeared to be the most contributable class of hydrocarbons in terms of their concentrations, followed by aromatics, and olefins, halogenated hydrocarbons was not detected. PVC wallpapers plentifully emitted TVOC above other wallpapers, and toluene was showed higher concentration of 10 times than natural wallpaper. In addition to, emission factor according to elapse was gradually decreased.