• 한국의류학회지
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• 제37권1호
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• pp.113-123
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• 2013

Clothes that retain and emanate body odor feel uncomfortable and unclean; subsequently, the adsorption, desorption and removal amounts of malodorous compounds from fabrics with different polarities were examined. 1-Octen-3-one, octanal and isovaleric acid, which are important malodor compounds from the body, were used as volatile organic compounds (VOC). Samples were prepared with unfinished and ${\beta}$-CD finished cotton, nylon and PET fabrics. The amounts of VOCs retained on the fabrics were measured using headspace GC-MS; in addition, the odor intensity of the samples were evaluated by 10 trained panelists. The amounts adsorbed were estimated by weight gain; however, moisture was found to have a larger effect on the increase in weight than VOCs. The polarity of the VOCs decreased in the order of isovaleric acid, octanal and 1-octen-3-one. Despite the exceptionally large amounts of octanal adsorbed on the nylon sample, the amounts of malodorous compounds adsorbed on fabrics increased with the decreasing VOC molecular weight. The unfinished PET sample adsorbed more VOCs than the unfinished-fabric samples. The odor intensity was mostly weaker in the ${\beta}$-CD finished fabrics than in the unfinished fabrics. The odor intensity of the ${\beta}$-CD finished fabrics was lower than unfinished fabrics. The amount of VOCs that remained on the soiled fabric samples after storing in air for 24 hrs decreased with the increasing VOC vapor pressure. Most VOCs were removed by washing; however, more VOCs were left on the ${\beta}$-CD finished fabrics than unfinished fabrics. The intensity of the odor from the unfinished PET and ${\beta}$-CD finished fabrics was stronger and weaker, respectively, than that of other fabrics, even when the same amounts of VOCs remained.

• Safety and Health at Work
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• 제2권3호
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• pp.210-217
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• 2011

Objectives: The purpose of this study was to measure the concentration of volatile organic compound (VOC)s originated from the chemicals used and/or derived from the original parental chemicals in the photolithography processes of semiconductor manufacturing factories. Methods: A total of four photolithography processes in 4 Fabs at three different semiconductor manufacturing factories in Korea were selected for this study. This study investigated the types of chemicals used and generated during the photolithography process of each Fab, and the concentration levels of VOCs for each Fab. Results: A variety of organic compounds such as ketone, alcohol, and acetate compounds as well as aromatic compounds were used as solvents and developing agents in the processes. Also, the generation of by-products, such as toluene and phenol, was identified through a thermal decomposition experiment performed on a photoresist. The VOC concentration levels in the processes were lower than 5% of the threshold limit value (TLV)s. However, the air contaminated with chemical substances generated during the processes was re-circulated through the ventilation system, thereby affecting the airborne VOC concentrations in the photolithography processes. Conclusion: Tens of organic compounds were being used in the photolithography processes, though the types of chemical used varied with the factory. Also, by-products, such as aromatic compounds, could be generated during photoresist patterning by exposure to light. Although the airborne VOC concentrations resulting from the processes were lower than 5% of the TLVs, employees still could be exposed directly or indirectly to various types of VOCs.

• 한국축산시설환경학회지
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• 제19권1호
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• pp.25-32
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• 2013

This study was performed to analyse the concentration of odorous compounds in the piggeries. Piggeries for different types of pigs include piglets, growing pigs, gestating and lactating sows. Slurry from these piggeries was sampled every month for chemical analysis. Short chain fatty acid (SCFA) was 9,862 ppm (piglet), 8,410 ppm (growing pigs), 6,791 ppm (fattening pigs), 3,508 ppm (lactating sows) and 1,687 ppm (gestating sows). Branched chain fatty acid (BCFA) was 1,634 ppm (piglet), 1,206 ppm (growing pigs), 868 ppm (fattening pigs), 493 ppm (lactating sows) and 185 ppm (gestating sows). Concentration of phenols was 209 ppm (piglet), 166 ppm (growing pigs), 127 ppm (fattening pigs), 85 ppm (lactating sows) and 36 ppm (gestating sows). Indoles was 18 ppm (piglet), 14 ppm (growing pigs), 8 ppm (fattening pigs), 6 ppm (lactating sows) and 4 ppm (gestating sows). Altogether, concentration of odorous compounds was decreased as pigs got aged.

• Elastomers and Composites
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• 제35권1호
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• pp.12-18
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• 2000

환경에 대한 관심과 정부의 규제 강화로 에폭시 코팅 산업 분야에서 발생되는 휘발성 유기 물질 방출을 최소화하기 위하여 꾸준히 기술 개발을 해오고 있다. 환경 친화적인 기술 개발의 일환으로 본 연구에서는 amine-epoxy adduct (AEA)형의 수용성 에폭시 경화제를 합성하였고, 그의 구조를 FT-IR, GPC, TG/DTA로 확인하였으며, 합성한 수용성 경화제를 이용하여 KER-828 그리고 KER-500과의 경화 물성을 비교 조사하였다. 실험 결과에 의하면 건조시간은 KER-828이 KER-500보다 빨랐으나 접착력 및 내 충격성은 KER-500이 우수하였다.

• Environmental Engineering Research
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• 제12권2호
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• pp.72-80
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• 2007

Experiments were conducted to identify the emissions from the car air freshener and to identify the formation of ultra-fine particles and secondary gaseous compounds during the ozone-initiated oxidations with emitted VOCs. The identified primary constituents emitted from the car air freshener in this study were $\alpha$-pinene, $\beta$-pinene, $\rho$-cymene and limonene. Formation of ultra-fine particles (4.4-160 nm) was observed when ozone was injected into the chamber containing emitted monoterpenes from the air freshener. Particle number concentrations, particle mass concentrations, and surface concentrations were measured in time dependent experiments to describe the particle formation and growth within the chamber. The irritating secondary gaseous products formed during the ozone-initiated reactions include formaldehyde, acetaldehyde, acrolein, acetone, and propionaldehyde. Ozone concentration (50 and 100 ppb) and temperature (30 and $40^{\circ}C$) significantly affect the formation of particles and gaseous products during the ozone-initiated reactions. The results obtained in this study provided an insight on the potential exposure of particles and irritating secondary products formed during the ozone-initiated reaction to passengers in confined spaces.

• 한국진공학회지
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• 제21권2호
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• pp.106-112
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• 2012

본 연구에서는 톨루엔 등의 휘발성 유기물의 흡착량을 정성, 정량적으로 연구할 수 있는 새로운 장비를 구축하였으며, 이를 이용하여 기존의 탄소를 기반으로 하는 다양한 흡착제와 원자층 증착으로 만든 $TiO_2$ 박막구조의 톨루엔 흡착에 대한 연구를 진행하였다. $TiO_2$ 박막구조의 흡착제가 기존의 탄소기반 흡착제보다 톨루엔 흡착량이 뛰어난 것을 입증하였으며, 이는 원자층증착으로 제조한 $TiO_2$ 박막 표면의 높은 농도의 OH 그룹의 높은 톨루엔 친화력과 연관성이 있는 것으로 나타났다. 또한 본장비를 이용하여 가역적인 흡착과 비가역적인 흡착을 구분할 수 있음을 보여주었다.

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2333-2336
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• 2010

$TiO_2$ thin films were synthesized on carbon fibers using chemical vapor deposition. We show that these films can exhibit extraordinarily high absorption capacities of toluene vapor. Such an absorption phenomenon of toluene at room temperature was not found for other $TiO_2$ samples. Upon toluene absorption change in the color (darkening) of the film was found, indicating that these films can be used as an indicator of the existence of volatile organic compounds in the indoor environments. By X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM), a high concentration of OH species and a unique layered structure were found for the $TiO_2$ films and these could be related to their high absorption capacity of toluene.

• 한국환경과학회지
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• 제7권5호
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• pp.573-580
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• 1998

This study examined the carbon dioxide ($CO_2$) pollution inside vehicles under low ventilation condition and evaluated the Air Quality System (AQS) for in-vehicle air quality using two techniques. The low ventilation condition is not recommended in order to keep oxygen-rich condition inside vehicles. Under the low ventilation condition, the in-vehicle $CO_2$ concentrations exceeded 1,000 ppm, the air qualify guidelines in the United States, Western Europe, and Japan, indicating more oxygen deficiency inside vehicles. On the contrary, with the AQS-on condition, the in-vehicle $CO_2$ concentrations were less than 1,000 ppm fer most of the driving time, indicating that the AQS could solve the problem of $CO_2$ accumulation inside vehicles under the low ventilation condition. The AQS test conducted by comparing carbon monoxide (CO) and volatile organic compound (VOC) concentrations inside two vehicles indicated that the AQS effectively decreased the in-vehicle concentrations by 21 to 36%, as compared to medium ventilation condition with the windows closed, the vent opened, and air conditioning on. In addition, The AQS test conducted by comparing the interior and exterior concentrations indicated that the AQS effectively decreased the in-vehicle concentrations by 18 to 31%, as compared to medium ventilation condition.

• 한국전기전자재료학회논문지
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• 제18권6호
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• pp.510-514
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• 2005

We have investigated the excitation-light source dependence of photo-catalytic efficiency for the benzene removal. The photo-catalytic module for the benzene removal is fabricated by a combination of GaN-based ultraviolet light-emitting diode (UV GaN-LED) and $TiO_2$ thin film coated on an aluminum plate. The benzene reduction rates of 365 nm and 375 nm modules at 60 mA junction current are approximately $8.95\;\%/Hr$ and $9.2\;\%/Hr$, respectively, which indicates that 365 nm GaN-LED is more effective than 375 nm GaN-LED. The benzene reduction efficiency is also noticeably dependent on the excitation wavelength and excitation-light power, as well as it is increased with the shorter wavelength and higher excitation power. This result exhibits that UV GaN-LED is useful to remove the volatile organic compounds (VOCs) existing in the environment.

• 멤브레인
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• 제23권2호
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• pp.129-135
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• 2013

도장공정에서 발생되는 휘발성 유기화합물의 회수를 위하여 중공사 분리막 모듈을 이용한 공정을 준비하여, 공급압력과 시간변화에 따른 휘발성 유기화합물의 회수에 대한 특성평가를 실시하였다. 중공사 분리막 모듈을 도장공정에 직접 적용한 결과, 투과된 휘발성 유기화합물의 농도는 투과시간과 압력의 증가됨에 따라 증가되었으며, 단일공정보다 다단공정이 더 우수한 분리성능을 나타내는 것을 확인하였다.