• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.8 s.251
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• pp.788-795
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• 2006

From the view of the environmental protection against the use of fossil fuels, the great of efforts have been exerted to find an effective method which is not only pollutant reduction but also high thermal efficiency. Reburning is a useful technology in reducing nitric oxide through injection of a secondary hydrocarbon fuel. In this paper, an experimental study has been conducted to evaluate the hybrid effects of reburning and selective non-catalytic reaction (SNCR) on $NO_x/CO$ reduction from oxygen-enriched LPG flame. Experiments were performed in flames stabilized by a co-flow swirl burner, which was mounted at the bottom of the furnace. Tests were conducted using LPG gas as main fuel and also as reburn fuel. The paper reported data on flue gas emissions, temperature distribution in furnace and various heat fluxes at the wall for a wide range of experimental conditions. Overall temperature in the furnace, heat fluxes to the wall and $NO_x$ generation were observed to increase by oxygen-enriched combustion, but due to its hybrid effects of reburning and SNCR, $NOx/CO$ concentration in the downstream has considerably decreased.

• Fire Science and Engineering
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• v.25 no.6
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• pp.27-31
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• 2011

In this study, combustion toxicity evaluation for building interior materials and study for toxicity as using FT-IR analysis. this experiment for the calculation of toxicity index, it using a cone calorimeter model in KS F ISO/TR 9122-4 as a fire model. It is following ISO 19702 procedure for assessing fire toxic gas using FT-IR. This experiment used calculation method for toxicity index (FED) among the international standards. $LC_{50}$ is a concentration that it can cause death to 50 % of experimental animal in 30 minutes - exposure gas test. comparison with the three kinds of toxicity fire gas of construction materials using toxicity index.

• Ocean and Polar Research
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• v.32 no.3
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• pp.291-297
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• 2010

In the summer of 2008 (August 4-14), vertical and horizontal distributions of inorganic nutrients and dissolved organic carbon (DOC) were measured in the southwestern East Sea. Concentrations of DOC were determined for the first time in the southwestern East Sea using the high-temperature combustion oxidation (HTCO) method, and results were compared with those measured by another laboratory. Concentrations of DOC ranged from 58 to 104 ${\mu}M$ in the upper 200 m, showing a typical decreasing pattern with depth. Generally, concentrations of DOC were relatively lower, with higher nutrient concentrations, in the upper layer of the coastal upwelling zone. Concentrations of DOC ranged from 54 to 64 ${\mu}M$ in the deep Ulleung Basin (200-1500 m), and were higher than those in the Pacific and Atlantic oceans. In association with rapid vertical ventilation of the euphotic, this difference indicates a larger accumulation of semi-labile DOC in the deep East Sea than in the major oceans. A correlation between apparent oxygen utilization (AOU) and DOC in the deep ocean of the East Sea revealed that only a small portion (<10%) of the sinking DOC, relative to the sinking particulate organic carbon (POC), contributes to microbial degradation. Our results present an important data set of DOC in the East Sea, which plays a critical role in carbon cycle modeling and sequestration.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.16-22
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• 2004

Dimethyl Ether (DME) has been considered as one of the most attractive alternative fuels for a compression ignition engine. The major advantage of DME-fuelled engine is a great potential for soot-free combustion without sacrificing an inherent high thermal efficiency of diesel engine, despite a necessity for modification of the conventional fuel injection system. An experimental study on DME and conventional diesel sprays was conducted by employing a common-rail type fuel injection system with a 5-holes sac type nozzle, including a constant volume vessel pressurized with nitrogen gas. The injection rates of DME and diesel fuel were recorded with the Bosch type injection rate meter. The injection delay of DME was shorter than that of diesel fuel. The measured injection rates of DME and diesel fuel were correlated with spray penetrations. The prediction method of spray penetration was established using the injection rates, which was verified with the Dent's penetration model and found to agree well for DME case.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.4
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• pp.462-472
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• 1999

De-NOx facility using Selective Catalytic Reduction method is the most widely applied one that removes NOx from flue gas emitted from combustion facility such as boiler for power generation engine incinerator etc. Reductant $NH_3\;or\;NH_4OH$ is sprayed into flue gas to convert NOx into $H_2O$ and $N_2.$ Good mixing between flue gas and $NH_3$ is the most important factor to increase reduction in catalytic layer and to reduce unreacted NH3 slip. Therefore the development of mixer device for mixing effect is one of the important part for SCR facility. Objectives of this study are to investigate the relation between flow and concentration field by observation at the wake of delta-wing type mixer. At the first stage qualitative measurement of flow field is conducted by flow visualization using laser light sheet in lab. scale wind tunnel. Also we have conducted the quantitative analysis by comparing flow field measurement using LDV with numerical simulation. On the basis of qualitative and quantitative analysis we investigate the dis-tribution of flow and concentration in flow model facility. The results of an experimental and compu-tational examination of the vortex structures shed from delta wing type vortex generator having $40^{\circ}$ angle of attack are presented, The effects of vortex structure on the gas mixing is discussed, too.

• YAKHAK HOEJI
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• v.26 no.4
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• pp.253-256
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• 1982

The organ distribution of mercury was examined in the rat after oral administration of a single dose of red mercuric sulfide (15mg Hg/kg). The concentration of total mercury in the organs and blood after 2, 4, 6, 8, 12, 24 and 72 hours of administration was determined by Quartz Tube Combustion-Gold Amalgamation Method. It was found that the maximal concentration of total mercury was in the kidneys and muscle within 24 hours and in the brain, heart, liver and blood within 48 hours. The descending order of the maximal organ and blood concentration was: kidneys(1.08ppm)>blood> muscle>heart>liver>brain. The accumulation states of total mercury in the rat organs were investigated by continuous administration of red mercuric sulfide (5mg Hg/kg/day) for 15 days. The mercury concentration increased progressively throughout the experimental period and the descending order of the highest level of mercury after 15 days was: kidneys (1.55ppm)>blood>liver. The concentration of alkyl mercury in brain, liver and kidneys also was measured after 7 and 15 days of consecutive administration of red mercuric sulfide (5mg Hg/kg/day). The concentration in the Kidneys and the liver was very low, but was significantly different from control group. The concentration in the brain was extremely low and was not significantly different from control group.

• Journal of ILASS-Korea
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• v.17 no.3
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• pp.140-145
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• 2012

Recent common-rail injector of a diesel engine needs more smaller nozzle hole to meet the stringent emission regulation. But, small nozzle hole diameter can cause nozzle coking which is occurred due to the deposits of post-combustion products. Nozzle coking has a negative effect on the performance of fuel injector because it obstructs the fuel flow inside a nozzle hole. In this study DFSS (Design for six sigma) method was applied to find the effect of nozzle design parameter on nozzle coking. Total 9 injector samples were chosen and tested at diesel engine. The results show that nozzle hole diameter and K-factor have more effect on nozzle coking than A-mass and hole length. Large hole diameter and A-mass, small hole length and K-factor give more positive performance on nozzle coking in these experimental conditions. But, a performance about nozzle coking and exhaust gas emission shows the opposite tendency. Further study is needed to find the relation between nozzle coking and emission characteristic for the optimization of injector nozzle design.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.2
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• pp.53-61
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• 2006

Axisymmetric numerical thermal analysis for a 3-dimensional regenerative cooling system in a rocket engine is carried out. To predict the accurate heat transfer with the stiff temperature distribution, several tests have been conducted for the grid size, the properties variation of the coolant and the combustion gas depending on temperature. The axisymmetric heat flux model is defined using fin efficiencies and is designed to be equivalent to the heat flux of the 3-dimensional coolant channel. For comparison purpose, the 1-dimensional analysis using Bartz equation is also conducted. The performance of the present model in predicting the cooling characteristics of a 3-dimensional regenerative cooling system is compared with the 3-dimensional results of RTE(Rocket Thermal Evaluation). It is found that the present method predicts much closer results to those of RTE code than 1-dimensional analysis.

• Journal of Electrochemical Science and Technology
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• v.1 no.2
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• pp.97-101
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• 2010

In order to apply hybrid capacitor, $Li_2Mn_3O_7$ was synthesized by combustion method using $LiNO_3$, $Li(CH_3COO){\cdot}2H_2O$ and $Mn(CH_3COO){\cdot}4H_2O$. Spinel pattern was identified the samples calcined over $400^{\circ}C$ in XRD. Intensity of $Mn_2O_3$ peak increased as the calcination temperature increased. To decide n/p ratio and to investigate electrochemical properties, charge-discharge tests of Li/$Li_2Mn_3O_7$ and Li/AC half-cell were carried out. Applying to AC/$Li_2Mn_3O_7$ hybrid capacitor, it had high discharge capacitance of 32.8 F/cc at 100 mA/g.

• Carbon letters
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• v.16 no.1
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• pp.1-10
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• 2015

In recent years, flame synthesis has absorbed a great deal of attention as a combustion method for the production of metal oxide nanoparticles, carbon nanotubes, and other related carbon nanostructures, over the existing conventional methods. Flame synthesis is an energy-efficient, scalable, cost-effective, rapid and continuous process, where flame provides the necessary chemical species for the nucleation of carbon structures (feed stock or precursor) and the energy for the production of carbon nanostructures. The production yield can be optimized by altering various parameters such as fuel profile, equivalence ratio, catalyst chemistry and structure, burner configuration and residence time. In the present report, diffusion and premixed flame synthesis methods are reviewed to develop a better understanding of factors affecting the morphology, positioning, purity, uniformity and scalability for the development of carbon nanotubes along with their correlated carbonaceous derivative nanostructures.