• Journal of the Korean Society of Combustion
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• v.11 no.2
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• pp.7-14
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• 2006

Catalytic combustion is one of the suitable methods for micro power source due to high energy density and it can be applied to micro structured chamber without consideration of quenching since it is flameless combustion. Catalyst loading in the micro structured combustion chamber is one of the most important issues in the development of micro catalytic combustors. In this research, to coat catalyst on the chamber wall, two methods were investigated. First, $Al_2O_3$ was selected as a support of Pt and $Pt/Al_2O_3$ was synthesized through the alumina sol-gel procedure. To improve the coating thickness and adhesion between catalyst and substrate, heat resistant and water solvable organic-inorganic hybrid binder was used. Porous silicon was also investigated as a catalyst support for platinum. Through the parametric studies of current density and etching time, fabrication process of $1{\sim}2{\mu}m$ of diameter and about $25{\mu}m$ depth pores was confirmed. Coated substrates were test in the micro channel combustor which was fabricated by the wet etching and machining of SUS 304. Using $Pt/Al_2O_3$ coated substrate and Pt coated porous silicon substrate, conversion rate of fuel was over 95 % for $H_2/Air$ premixed gas.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.373-377
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• 2011

Fire patterns have been used to determine the origin and cause of fires in every setting imaginable. However, it is very difficult to identify fire patterns from the fire-damaged remains of a devastated structure. If someone was killed by the fire, it is possible to identify fire patterns by analyzing the concentration of carbon monoxide-hemoglobin in the body of deceased as well as the pace of the fire. For example, a low level of carbon monoxide-hemoglobin in the body of the dead indicates a rapid fire with accelerants and the death was caused by severe heat and thick toxic fumes. However, a high level of carbon monoxide-hemoglobin in the body of the dead demonstrates that the fire was slow and/or there was a flameless form of combustion. Thus, this study identifies fire patterns through analyzing the level of carbon monoxide-hemoglobin concentration on the dead from the fire.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.466-471
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• 2004

In gas turbines, excess air for combustion is available and therefore lean premixed combustion is the most promising approach to the significant reduction of thermal NOx emissions. At lean conditions, however, flame stability is inherently worse and hence combustion tends to be incomplete. Efforts have been devoted toward extending the operating range of complete combustion at leaner conditions. One of them is the lean-lean two-stage combustion where lean to ultra-lean secondary mixtures are mixed with the hot burned gas from the primary stage. Conventional flame combustion or flameless reaction are initiated depending on the conditions of the secondary zone. In the first part of the present study, the effects of fuel injection on the emissions and flame stability were investigated for a single tubular flame, In the second part, the emissions and flame stability were studied for a two-stage combustor with secondary mixture injected through the tangential slots on a cylindrical combustor wall. The effects of the ratio of air flow rates to the primary and secondary zones on the emissions and combustion characteristics were investigate.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.1
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• pp.1-7
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• 1995

The exposure levels of chromium and nickel for chromeplating workers were evaluated. Chromium and nickel concentrations in urine and serum from 82 exposed workers and 69 controls, who were not exposed occupationally to metals, were analyzed by flameless atomic absorption spectrophotometry. The results were as follows: 1. Chromium concentrations in urine of exposed group and control were $3.49{\pm}1.83g/g$ of creatinine, $5.59{\pm}2.83g/g$ of creatinine, and in serum were $0.69{\pm}0.30g/l$, $2.31{\pm}1.16g/l$ respectively. There were significant difference of concentrations for chromium in urine and serum by group respectively. 2. Nickel concentrations in urine of exposed group and control were $0.92{\pm}0.23g/g$ of creatinine, $2.20{\pm}1.93g/g$ of creatinine, and serum concentrations were $0.52{\pm}0.34g/l$, $1.41{\pm}0.74g/l$ respectively. There were significant difference of concentrations for nickel in serum by groups statistically. 3. Chromium and nickel concentrations in urine and serum of exposed groups were not significant by workplaces(grinding, electroplants, packaging).

• Journal of Preventive Medicine and Public Health
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• v.23 no.3 s.31
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• pp.255-261
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• 1990

Taxi drivers are exposed to vehicular exhaust aerosols which are a mar source of atmospheric lead pollution in Korea where lead additives are incorporated in petrol. To investigate the blood lead concentration, their correlation factors and influences on taxi drivers, samples were collected from 90 taxi drivers who were living in the Taegu City, during August, 1989. Blood lead concentration was estimated by the atomic absorption spectrophotometer (IL.551) equipped with flameless furnace atomizer (IL.665). The results were analyzed statistically and compared with control group selected urban population. The mean blood lead concentration of taxi drivers and control group were $26.34{\pm}6.53{mu}g/dl\;and\;20.77{\pm}4.80{\mu}g/dl$ respectively (p<0.01). No significant correlation was observed between the blood lead concentration of taxi drivers and driver career (r=0.093). There were no difference of statistical significance in the blood lead concentration of smokers and nonsmokers.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1049-1055
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• 2012

The fiber mat catalytic burner that uses infrared radiative heat obtained by flameless catalytic combustion was manufactured and tested to investigate its combustion characteristics. About 9 to 17% of combustion heat was released by sensible heat during the premixed catalytic combustion depend on combustion condition. To find out radiation intensity with distance between catalytic burner and sample, the equation that calculate the receiving surface of radiative energy under the fiber mat catalytic burner was driven. This equation was well correlated with the drying rate of melamine. The drying experiments were carried out to the melamine, wood chip and agricultural pallet by using the fiber mat catalytic burner and the energy efficiency was calculated from drying rate of them. The energy efficiency of the fiber mat catalytic burner reaches to 79% in maximum for drying of the wood chip.

• YAKHAK HOEJI
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• v.30 no.6
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• pp.281-287
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• 1986

Atmospheric mercury was collected by gold amalgamation method and analyzed by cold flameless atomic absorption spectrometry. The distribution of atmospheric mercury was investigated at seven location (rural I, II, industrial I, II, University and the center of urban) The amount of atmospheric mercury collected at the rural area I (Mt. Seolack) ranged from 0.7 to 1.8ng/$m^3$, and mean value was 1.2ng/$m^3$ (n=4), at the rural area II (Buyeo) ranged from 0.8 to 5.1 ng/$m^3$, and mean value was 2.0ng/$m^3$ (n=8), at the area of the center of urban (Jong-ro 3 Ga, Seoul) ranged from 22.7 to 43.1ng/$m^3$, and mean value was 35.1ng/$m^3$ (n=12), at tae residential area I (Galak Dong, Seoul) ranged from 2.2 to 5.1ng/$m^3$, and mean value was 3. 5 ng/$m^3$ (n=6) at the Chung-Ang University (Heukseok Dong, Seoul) ranged from 2.2 to 176.2 ng/$m^3$, mean value was 36.8 ng/$m^3$ and median value was 16.0 ng/$m^3$ (n=188), at the residential area II (Goowal Dong, Inchon) ranged from 6.4 to 20.7 ng/$m^3$, and mean value was 13.1 ng/$m^3$ (n=10), and at the industrial area (Songhyun Dong, Inchon) ranged from 13.9 to 88.3 ng/$m^3$, and mean value was 38.9 ng/$m^3$ (n=12). The behavior of atmospheric mercury concentration at Chung-Ang University showed high in day time and summer, but low in night-time and winter.

• Fire Science and Engineering
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• v.26 no.3
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• pp.40-48
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• 2012

Fire patterns have been used to determine the origin and cause of fires in every setting imaginable. However, it is very difficult to identify fire patterns and causes from the fire-damaged remains of a devastated structure. If someone was killed by the fire, it is possible to identify fire patterns by analyzing the Hb-CO concentration in charred bodies of deceased as well as the pace of the fire. For example, a low level of Hb-CO concentration in the charred bodies indicate a rapid fire with accelerants and the death was caused by severe heat and thick toxic fumes. However, a high level of Hb-CO concentration in the charred bodies demonstrates that the fire was slow and/or there was a flameless form of combustion. Thus, it is possible to identify fire patterns through analyzing the level of Hb-CO concentration on the dead from the fire. In this study, the Hb-CO concentration in the charred bodies was from 3 % at the case of gas burning oneself to death to 93 % at the death caused by smoldering fire.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.276-282
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• 1989

To investigate the contamination level and total dietary intake of Hg in common restaurant meals of Seoul area, 125 samples of 5 typical meals were collected and determined for their total Hg contents by flameless atomic absorption sepctrophotometry. The average concentrations of Hg were 0.186ppm in drained residues and 0.007ppm in fluids, in which two samples yeukkye-jang and bibim-bab from two sites showed such a high level of 20-30 times of mean values. The average amount of Hg per meal excluding the two samples was $79.6{\mu}g$ and it was not significantly different among different meals. The daily dietary intake of total Hg from 3 restaurant meals was estimated to be $239{\mu}g$, which was 5 times higher than the FAO/WHO limit of $42.9{\mu}g$.

• Journal of Energy Engineering
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• v.17 no.2
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• pp.100-106
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• 2008

Flameless fiber mat catalytic burners have been known as an effective heat source in industrial drying processes since heat obtained from combustion can be transferred to absorptive body by far-infrared radiation. In order to extend the application of fiber mat catalytic burner, novel fiber mat catalytic burners were manufactured and combustion characteristics of them were investigated. For diffusive catalytic burners, the efficiency of combustion was significantly affected by the installation direction and the temperature of catalytic bed perimeter influenced on the diffusion rate of oxygen which determined the combustion efficiency of catalytic burner. It was seen in premixed catalytic combustion that air content in premixed fuel gas was optimized at slightly higher than theoretical amount of air. Combustion heat released higher than 70% by radiant heat in premixed catalytic combustion likewise diffusive catalytic combustion.