• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.687-688
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• 2008

• Journal of Korean Society of Environmental Engineers
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• v.34 no.8
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• pp.541-548
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• 2012

The objective of this study was to investigate emission characteristics of odorous compounds from the pneumatic waste collection plants (namely, A and B sites). The air samples were collected from each site, at a carrier gas inside the plant and an exhaust gas, to analyze complex odor and 22 odorous compounds. Ammonia, sulfur compounds, and acetaldehyde were the critical odorous components generated in the plants studied. Characteristics of odor at exhaust outlet varied according to the type of odor control engineering. In the analysis of the odor contribution degree of odor components based on odor threshold, site A shows that the odor contribution of dimethyl sulfide was found to be 26%, acetaldehyde 18%, and methyl mercaptan 14%. For site B, methyl mercaptan was 56% and both hydrogen sulfide and dimethyl sulfide were 15%.

• Analytical Science and Technology
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• v.17 no.5
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• pp.410-415
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• 2004

In order to learn the emission characteristics of hazardous pollutants associated with environmental tobacco smoking (ETS), we measured the concentrations of major aromatic VOC and carbonyl compounds released from ETS. By acquiring the different smoke types of ETS, we were able to determine that the concentrations of those species range from ppb (normal exhaled air of smoker prior to smoking) to ppm levels (direct release of ETS without filter). Using these measurement data, we also evaluated the body-retaining rate of these compounds as the result of ETS. The results of our analysis indicated that predominant portion of them (e.g., > 99%) are retained as the result of cigarette smoking. To learn more about the potential impact of ETS, more extensive study may be required to assess the gross picture of pollutant deposition inside respiratory intake and their health-effects.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.360-367
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• 2017

This study was carried out to compare the characteristics of low density fiberboards (LDFs) manufactured with different adhesive types such as melamine urea formaldehyde (MUF), phenol formalehyde (PF), emulsified MDI (eMDI) and latexes resins. As results, hard LDFs were successfully manufactured by MUF, PF and eMDI resins. Thermal conductivities of all LDFs were significantly lower than commercial medium density fiberboard. Especially, all LDFs showed comparable thermal insulation performance with extruded polystyrene foam (XPS). LDF manufactured with eMDI resins showed the highest physical properties such as thickness/length swelling by water absorption and bending strength.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.86-95
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• 2003

Potential mechanisms by which vitamin E improves oxidative stability of myoglobin are documented. The basis by which this lipid-soluble antioxidant, ${\alpha}$-tocopherol, protects water-soluble oxymyoglobin is beginning to be understood. Recent evidence suggests that ${\alpha}$-tocopherol delays the release of prooxidative products of lipid oxidation from biomembranes, which in turn delays oxymyoglobin oxidation and the concomitant loss of desirable beef color. ${\alpha}$, ${\beta}$-Unsaturated aldehydes are one class of lipid oxidation products that enhance oxymyoglobin oxidation in vitro and appear to act by covalently binding to the protein. If ${\alpha}$-tocopherol delays the formation of these reactive aldehydes, then this could inhibit the prooxidative effect of these oxidation products toward oxymyoglobin. Additionally, ${\alpha}$-tocopherol may exert part of its color-stabilizing effect in beef by enhancing the metmyoglobin reduction.

• Journal of the Korean Chemical Society
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• v.47 no.3
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• pp.213-219
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• 2003

The photochemical transformation of carbon monoxide in aqueous solution has been investigated at $25{\pm}0.1^{\circ}C$using ZnO as a photocatalyst. After irradiation of 253.7 nm UV light in the solution, carboxylation and carbonylation processes were carried out, and the formation of formic acid, oxalic acid, glyoxylic acid, formaldehyde and glyoxal was observed. The formation of the products depended on the pH values in the solution. The yield of formaldehyde and glyoxal increased in acidic solution whereas it decreased in basic solution. When the pH values in the solution increased above 11.5, the yield of formic acid increased rapidly. The initial quantum yields of the products were determined and the probable mechanisms for the reactions were presented on the basis of the products analysis.

• Journal of the Korean Applied Science and Technology
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• v.29 no.1
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• pp.13-18
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• 2012

A die casting mold releasing agent was prepared from aqueous mixture of powdery carbon black and water soluble natural polymeric materials such as xanthan gum(X-gum) and carboxymethyl cellulose(CMC), which were used as thickening agent as well as curing agent with aldehydes. The suitable concentration of natural polymers for stable dispersion of carbon black in water was 0.25 wt% of X-gum or 1.0 wt% of CMC. When CMC was used less than 1 wt%, the final carbon black disperion showed a rapid phase separation. The adhesion of carbon black releasing agent on glass plate was improved with the amount of crosslinking agent, glutaraldehyde and chain extender, oligosaccharide. However, the affinity of carbon black releasing agent prepared with X-gum was stronger than that with CMC on glass plate. The final carbon black mold releasing agents prepared under our mixing conditions can be applied to the production of castings of high quality with good workability and without worthening evironmental situations.

• Clean Technology
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• v.20 no.2
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• pp.116-122
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• 2014

Various types of MOFs (metal-organic frameworks) were prepared via hydrothermal and post-grafting methods and applied as catalysts for the synthesis of jasminaldehyde, one of the representative perfume intermediates, by Aldol condensation of benzaldehyde with heptanal. Although both acid and base sites could catalyze the reaction, the catalytic performance was strongly dependent on the physical properties as well as the nature of functionalization on MOFs. While the use of sulfonated MOF catalysts led to decrease of jasminaldehyde selectivity regardless of MOFs used, the selectivity change was found to rely on the MOF types in the case of the amine-functionalization. Among the catalysts tested, MIL-101 shows the best catalytic performance, which may suggest that MIL-101 has suitable acid properties to promote the Aldol condensation and the large pore of MIL-101 is also advantageous to alleviate the diffusion problem of bulky products.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.223-230
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• 2014

This study examined emission characteristics of far-infrared ray, formaldehyde, volatile organic compounds and deodorization rate of particleboard prepared at different target board densities and resin content levels, using the xylem part of Broussonetia Kazinoki Sieb. The deodorization rate increased, as the target density of board and resin content increased. Emission rates of the far-infrared ray and total volatile organic compounds (TVOCs) were 0.892~0.899, and $0.074mg/m^2{\cdot}h$ for particleboard prepared with the resin content of 13% and target density of $0.6g/cm^3$ while the deodorization rate was 80~90% for the same particleboard. The formaldehyde emission factor ranged from $0.004mg/m^2{\cdot}h$ to $0.006mg/m^2{\cdot}h$ for all particleboard fabricated at different resin content and target densities. These results indicate that particleboard prepared from the xylem part of Broussonetia Kazinoki Sieb have a potential as a building construction material.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.346-354
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• 1987

The voflatile fraction from Korean mandarin (Citrus reticula) and valencia orange essence oil were analyzed by capillary gas chromatography and the separated components were identified from their retention time and mass pectrum. The essence oil were extracted with methylene chloride after steam distillation. The major volatile constituents of mandarin and sweet orange was limonene which accounted for 68% of total volatiles in mandarin and 87% in sweet orange. The 31 components identified from mandarin include 11 hydrocarbones, 1 ester, 10 alcohols, 4 aldehydes, 5 miscellaneous. The following 37 components were identified in sweet orange; 12 hydrocarbones, 1 ester, 11 alcohols, 8 aldehydes, 5 misecellaneous. Mandarin contained more octanal, ${\alpha}-terpinene$, terpineol, styrene, dcitronellol, citronellal, citral and farnesol while orange included more sweet orange, myrcene, ${\beta}-pinene$, linallol, decanol, ${\beta}-copaene$, elemene, ${\beta}-cadinene$, valencene.