• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.742-747
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• 2008

Formaldehyde(HCHO) and total volatile organic compounds(VOCs) can cause adverse health effects to the building occupants and may contribute to symptoms of 'Sick Building Syndrome'. These chemical contaminants are emitted from furnishings and electronic equipments as well as building materials. The purpose of this study is to measure and analyze VOCs and HCHO emission concentration from furnitures composed of wood materials including various chemicals by the large chamber method. This paper presents experiment results on the emission concentration of TVOCs and HCHO released from furnitures, such as bed, kitchen, sofa and table by a large chamber($24m^3$). The temperature and air humidity in the chamber are controlled to $25{\pm}1{\circ}C$ and $50{\pm}5%$ for this experiment. When the air change rate is $0.5hr^{-1}$, the background concentrations within the large chamber are below $50{\mu}g/m^3$ for TVOC, $5{\mu}g/m^3$ for HCHO and individual VOCs. The study is investigated the characterization of the chemical emission TVOC and HCHO concentrations and unknown VOCs from 6 furnitures.

• Journal of the Korean Wood Science and Technology
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• v.36 no.2
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• pp.39-45
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• 2008

Formaldehyde and volatile organic compounds (VOCs) are emitted from wood-based panels that have been made using wood particles, wood fiber, wood chips, formaldehyde-based resins and so on. In this study, we examined formaldehyde and total VOCs (TVOC) emission behaviors for plywood overlaid with water-soluble phenolic resin impregnated linerboard (PL), and two kinds of surface materials (decorative veneer and pre-impregnated finishing foil) that were adhered onto the PL that named DPL and PPL. EVA (ethyl vinyl acetate) was used to overlay the decorative veneer and pre-impregnated finishing foil on the plywood with water-soluble phenolic resin impregnated linerboard by a hot press instrument. The debonding test and accelerated aging test were conducted to assess their mechanical properties. Formaldehyde and TVOC emission concentrations were measured using the FLEC method and a VOC Analyzer, respectively. The debonding test results of PL, DPL and PPL were 1.2, 1.5, and $0.5N/mm^2$, respectively. The surface appearance of the samples were not changed after the accelerated aging test. The PL and DPL exhibited reduced formaldehyde and TVOC emission levels, respectively. In the case of PPL, the VOC value was relatively higher than those of PL and DPL.

• Journal of Environmental Health Sciences
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• v.30 no.2
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• pp.92-97
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• 2004

Three methods for VOCs emissions control in indoor air are reduction at the source, ventilation between indoor and outdoor, and removal. The best alternative should be to replace highly emitting sources with sources having low emissions, but the pertinent information on VOCs is not always available from manufactures. Other ways of improving indoor air quality are needed. It is to increase the outside fresh-air flow to dilute the pollutants, but this method would generally provide only a dilution effect without destruction in residence. An ideal alternative to existing technologies would be a chemical oxidation process able to treat large volumes of slightly contaminated air at normal temperature without additional oxidant such as ozone generator and ion generator. Photocatalytic oxidation(PCO) represents such a process. It is characterized by a surface reaction assisted by light radiation inducing the formation of superoxide, hydroperoxide anions, or hydroxyl radicals, which are powerful oxidants. In comparison with other VOCs removal methods, PCO offers several advantages. The purpose of this study was to explore the possibilities for photocatalytic purification of slightly contaminated indoor air by using visible light such as flurescent visible light(FVL). In this study, a PCO of relatively concentrated benzene using common FVL lamps was investigated as batch type and total volatile organic compounds(TVOCs) using a common FVL lamp and penetrated sun light over window. The results of this study shown the possibility of TiO$_2$ photocatalyst application in the area of indoor air quality control.

• Journal of Environmental Health Sciences
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• v.37 no.3
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• pp.201-208
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• 2011

Objective: Emissions of volatile organic compounds (VOCs) from municipal wastewater treatment plants and industrial wastewater are often overlooked as sources of exposure to toxic chemicals. VOCs from such sources evaporate readily into the air and may have significantly adverse impacts on public health. The present study aimed to establish the concentration of VOCs released from Jangrim-sinpyoeng Municipal and Industrial Wastewater Treatment plant (JWTP) in Busan, South Korea and assess the causes of the odor/stench in the surrounding residential facilities. Stench intensity, frequency and release time, and wind direction were also monitored. Methods: Onsite data were collected on a daily basis from a laboratory located on the JWTP premises through a period spanning 2006 to 2010. A second set of data was obtained in 2006 by conducting a questionnaire survey with 210 respondents living near JWTP. The experimental and survey data were analysed statistically using the SPSS package. Results: The survey results showed that people residing around JWTP strongly perceive a stench from the plant. The intensity of the stench was influenced significantly by wind direction and the location of the apartments facing the JWTP. Public participation formed a significant step in determining the quality of the study environment. Conclusion: Onsite data and survey data obtained in 2006 indicate that the nature of the odor experienced by residents is due to the intensity of total VOCs released by JWTP. However, additional research is needed to determine the effects of the VOC pollution on public health and quality of life.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.29-35
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• 2013

A Nodulisporium sp. (Hypoxylon sp.) has been isolated as an endophyte of Thelypteris angustifolia (Broadleaf Leaf Maiden Fern) in a rainforest region of Central America. It has been identified both on the basis of its morphological characteristics and by scanning electron microscopy as well as ITS sequence analysis. The endophyte produces volatile organic compounds (VOCs) that have both fuel (mycodiesel) and use for biological control of plant disease. When grown on potato dextrose agar, the organism uniquely produces a series of ketones, including acetone; 2-pentanone; 3-hexanone, 4-methyl; 3-hexanone, 2,4-dimethyl; 2-hexanone, 4-methyl, and 5-hepten, 2-one and these account for about 25% of the total VOCs. The most abundant identified VOC was 1,8 cineole, which is commonly detected in this group of organisms. Other prominent VOCs produced by this endophyte include 1-butanol, 2-methyl, and phenylethanol alcohol. Moreover, of interest was the presence of cyclohexane, propyl, which is a common ingredient of diesel fuel. Furthermore, the VOCs of this isolate of Nodulisporium sp. were selectively active against a number of plant pathogens, and upon a 24 h exposure caused death to Phytophthora palmivora, Rhizoctonia solani, and Sclerotinia sclerotiorum and 100% inhibition to Phytophthora cinnamomi with only slight to no inhibition of the other pathogens that were tested. From this work, it is becoming increasingly apparent that each isolate of this endophytic Nodulisporium spp., including the Daldina sp. and Hypoxylon spp. teleomorphs, seems to produce its own unique set of VOCs.

• Environmental Analysis Health and Toxicology
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• v.27
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• pp.8.1-8.10
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• 2012

Objectives: The goal was to model and quantify the atmospheric concentrations of volatile organic compounds (VOCs) as the result of the Hebei Spirit oil spill, and to predict whether the exposure levels were abnormally high or not. Methods: We developed a model for calculating the airborne concentration of VOCs that are produced in an oil spill accident. The model was applied to a practical situation, namely the Hebei Spirit oil spill. The accuracy of the model was verified by comparing the results with previous observation data. The concentrations were compared with the currently used air quality standards. Results: Evaporation was found to be 10- to 1,000-fold higher than the emissions produced from a surrounding industrial complex. The modeled concentrations for benzene failed to meet current labor environmental standards, and the concentration of benzene, toluene, orthometa- para-xylene were higher than the values specified by air quality standards and guideline values on the ocean. The concentrations of total VOCs were much higher than indoor environmental criteria for the entire Taean area for a few days. Conclusions: The extent of airborne exposure was clearly not the same as that for normal conditions.

• Journal of odor and indoor environment
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• v.17 no.4
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• pp.362-371
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• 2018

Indoor Volatile organic compounds (VOCs) are classified as known or possible toxicants and odorants. This study characterized VOC levels in 11 homes in an area in the capital of Seoul by using two different methods of VOCs sampling, which are the active sampling using a thermal sorption tube and the passive sampling using a diffusion sampler. When using the active sampling method, the total target VOC concentration ranged from 41.7 to $420.7{\mu}g/m^3$ (mean $230.4{\mu}g/m^3$ ; median $221.8{\mu}g/m^3$) during winter and 21.3 to $1,431.9{\mu}g/m^3$ (mean $340.1{\mu}g/m^3$; median $175.4{\mu}g/m^3$) during summer. When using the passive method, 29.6 to $257.5{\mu}g/m^3$ (mean $81.8{\mu}g/m^3$; median $49.4{\mu}g/m^3$) during winter and 1.2 to $5,131.1{\mu}g/m^3$ (mean $1,758.8{\mu}g/m^3$; median $1,375.1{\mu}g/m^3$) during summer. Forty-nine VOCs were quantified and toluene showed the highest concentration regardless of the season and the sampling method studied. The distribution of VOCs was relatively varied by using the active method. However, it showed a low correlation with indoor environmental factors such as room temperature, humidity and ventilation time. The correlation between indoor environmental factors and VOCs were relatively high in the passive method. In particular, these characteristics were confirmed by principal component analysis.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.291-295
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• 2011

A bake-out process using auto switchgear for five days was performed to evaluate the reduction effect of the concentration of volatile organic compounds (VOCs) and formaldehyde in a newly-built elementary school gymnasium. Reduction rates of VOCs were observed as followings: 38.2, 64.2, 86.3, 80.2, and 71.5% for benzene, toluene, ethylbenzene, xylene, and styrene, respectively, which satisfies the indoor air quality standards of newly-built apartment houses in Korea. The reduction rate of total VOCs and formaldehyde were 67.0 and 24.7%, respectively. Those results proved that the bake-out process using auto switchgear was effective for reducing indoor air pollutants.

• Journal of the Korean Society of Food Culture
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• v.2 no.1
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• pp.25-31
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• 1987

We have examined to evaluate the taste compounds of damchi-jeotguk(concentrated sea mussel extract) which is a kind of traditional processed sea food in Korea. The contents of such compounds as free amino acids, nucleotides their and related compounds, non-volatile organic acid and fatty acid composition were analyzed. The content of total free amino acids was 10520.5mg/100g on dry basis and the major ones were glycine, arginine, aspartic acid and glutamic acid. These amino acids were resulted as 55.7% of total free amino acids in damchi-jeotguk. Hypoxanthine was the highest content($8.77\;{\mu}mole/g$, dry basis) of nucleotides and their related compounds. Free amino acid-N was the most abundant, resulting 53.3% of extractive nitrogen which was 3490.2mg/100g on dry basis and next ammonia-N, nucleotide-N and TMAO-N in order. The major non-volatile organic in damchi-jeotguk were succinic acid(125.5mg/100g, dry basis) and lactic acid 91.9mg/100g, dry basis). In this fatty acid composition of total lipid, polyenoic acid was abundant holding 45.5%. The major fatty acids were 16 : 0, 18 : 2, 22 : 6, 18 : 1 and 20 : 5. It was concluded from the omission test and chemical analysis that the major taste compounds of damchi-jeotguk were free amino acids and non-volatile organic acids.

• Food Science and Preservation
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• v.17 no.5
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• pp.616-624
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• 2010

We compared the physicochemical properties of, and volatile components in various commercial fruit vinegars (made from apples, grapes, and persimmons). Total acidity was highest in grape vinegars. Significant between-sample differences were evident in total and reducing sugar contents. Brownness, turbidity, and overall color difference (the ${\Delta}E$ value) were highest in persimmon vinegars. Free sugars were composed mainly of fructose, glucose, sucrose, and maltose. Major organic acids were present in the (descending abundance) order acetic acid, oxalic acid, citric acid, malic acid, and succinic acid, among-samples difference were negligible. Nine-essential free amino acids were detected in nine types of grape and persimmon vinegars, and in six varieties of apple vinegar. Among 17 types of volatile compounds identified in apple vinegars, 12 in grape vinegars, and 33 in persimmon vinegars, the main volatile components were acetic acid, ethyl acetate, isoamyl acetate, isovaleric acid, isoamyl alcohol, propanoic acid and phenethyl acetate. Volatile chemicals in commercial fruit vinegars were effectively analyzed using a SAW e-nose.