• Journal of the Korean Society of Combustion
• /
• v.15 no.4
• /
• pp.22-28
• /
• 2010

The Direct Quadrature Method of Moments (DQMOM) has been presented for the solution of population balance equation in the wide range of the multi-phase flows. This method has the inherently interesting features which can be easily applied to the multi-inner variable equation. In addition, DQMOM is capable of easily coupling the gas phase with the discrete phases while it requires the relatively low computational cost. Soot inception, subsequent aggregation, surface growth and oxidation are described through a population balance model solved with the DQMOM for soot formation. This approach is also able to represent the evolution of the soot particle size distribution. The turbulence-chemistry interaction is represented by the laminar flamelet model together with the presumed PDF approach and the spherical harmonic P-1 approximation is adopted to account for the radiative heat transfer.

• Rubber Technology
• /
• v.12 no.1
• /
• pp.1-7
• /
• 2011

Nanotechnology is the fast becoming key technology of the $21^{st}$ century. Due to its fascinating size-dependent properties, it has gained significant important in various sectors. Myths are being formed on the proverbal nanotechnology market, but the reality is the nanotechnology is not a market but a value chain. The chain comprises of - nanomaterials (nanoparticles) and nanointermediates (coatings, compounds, smart fabrics). Elastomer based nanocomposites reinforced with low volume fraction of nanofillers is the first generation nanotechnology products and it has attracted great interest due to their fascinating properties. The incorporation of nanofillers such as nanolayered silicates, carbon nanotubes, nanofibers, metal oxides or silica nanoparticles into elastomers improves significantly their mechanical, thermal, barrier properties, flame retardency etc., Extremely small particle size, high aspect ratio and large interface area yield an excellent improvement of the properties in a wide variety of the materials. Uniform dispersion of the nanofillers is a general prerequisite for achieving desired properties. In this paper, current developments in the area of elastomer based nanocomposites reinforced with layered silicate and carbon nanotube fillers are highlighted.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.129-129
• /
• 2006

Conventional solvent-based polyurethane (PU) is well established for wide applications, such as textile treatments, surface coating, adhesive and so on. Due to the demands of safety, economic, and environmental protection, the solvent-based PU is restricted and has been phasing out and aqueous-based PU is becoming the world market trend, which is an environmental friendly product. The chemical resistance, physical and mechanical properties of aqueous-based PU are still not competible with solvent-based PU. Because of aqueous-based PU is a linear thermoplastic polymer with lower average molecular weight. Their improvements are normally performed by a post-curing reaction or a polymer hybridization to enhance the polymer cross-linking density. Hybridization of PU with aqueous-based epoxy resin or acrylate emulsion and then cured by a curing agent for improving the performance properties and reducing the cost of aqueous-based PU.Furthermore, a special function is added to aqueous-based PU increasing the application value, for examples, flame retardation, polymeric dyes, hydrophilic and etc.

• Journal of Sensor Science and Technology
• /
• v.19 no.2
• /
• pp.67-86
• /
• 2010

Hydrogen is emerging as clean fuel and important industrial raw materials. The hydrogen gas is not sensed by the human olfactory system, But the combustion characteristics of hydrogen is that the ignition is very easy, the propagation speed of the flame is very fast and explosion limits is a wide range of 4 %~75 %. Therefore it is extremely in danger, and the need for its leakage detection technologies is especially important in places such as a production, transportation, storage and usage. The hydrogen sensors are classified with ceramic type, semiconductor type, optical type, electrochemical type and so on. Hydrogen sensors and their technologies are reviewed in detail for materials, fabrication process, sensing characteristics, good point and faults, and production and utilization of sensors be discussed.

• Journal of Advanced Navigation Technology
• /
• v.13 no.6
• /
• pp.1011-1016
• /
• 2009

In this paper, we propose the method of fire detection. A wide distribution of CCTV cameras (Closed Circuit Television) in many public areas can be used not only for video surveillance systems but also for detecting fire occurrence. A proposed approach is based on visual information through a static camera. Video sequences are analyzed to find fire candidates and then spatial analyses procedure for detected fire-like color foreground is carried out. From the simulation results, our method showed the best performance when spatial and temporal fire candidates changes rapidly and close to fire motion.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.04a
• /
• pp.405-408
• /
• 2003

The soild phase microextraction(SPME)fiber which contains 100${\mu}{\textrm}{m}$ polydimethyl siloxane of a stationary phase was used for the analysis of volatile organic compounds contained in aqueous solution. volatile organic compounds, which were spiked in blank water and extracted by the headspace SPME techique, were analyzed by gas chromatography/flame ionization detector(GC/FID). The optimu condition of SPME fiber is determined that the analytes were extracted for 40min from extracts by using PDAfS100${\mu}{\textrm}{m}$ fiber. This new method could have wide application for the analysis of VOCs in aqueous solution.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1999.11a
• /
• pp.171-180
• /
• 1999

In this study, the burning velocity of LFG and LFG mixing fuels related with flame stabilization have been analyzed numerically using C3 reaction mechanism which consists of 92 species and 621 reaction for using LFG. The results show that the burning velocities of LFG and LFG mixing fuels are obtained as a function of CH$_4$ and LFG percent in stoichiometric conditions. Also, a correlation of the burning velocities LFG and LFG mixing fuels are obtained over a wide range of equivalence ratio. The comparison of burning velocity from correlation with that calculated numerically show good agreements. From these results, the proposed burning velocity correlations for LFG and LFG mixing fuels can be applied for the practice of LFG.

• Bulletin of the Korean Chemical Society
• /
• v.21 no.11
• /
• pp.1101-1105
• /
• 2000

A simultaneous determination method of BTEX (benzene, toluene, ethylbenzene, o,m.p-xylene) and TPH (kerosene, diesel, jet fuel and bunker C) in soil with gas chromatography/flame ionization detection (GC-FID) was described. The effects of extracti on method, extraction solvent, solvent volume and extraction time on the extraction performance were studied. A sonication method was simpler and more efficient than Soxhlet or shaking methods. Sonication with 10 mL of acetone/methylene chloride (1 : 1, v/v) for 10 min was found to be optimal extraction conditions for 20 g of soil. Peak shapes and quantification of BTEX and TPH were excellent, with linear calibration curves over a wide range of 1-500 mg/L for BTEX and 10-5000 mg/L for TPH. Good reproducibilities by sonication were obtained, with the RSD values below 10%. By using about 20 g of soil, detection limits were 0.8 mg/L for BTEX and 10 mg/L for TPH. The advantages of this procedure are the use of simple and common equipment, reduced volumes of organic solvents, rapid extraction periods of less than 20 min, and simultaneous analysis of volatile and semivolatile compounds.

• Journal of the Korean Chemical Society
• /
• v.58 no.3
• /
• pp.283-288
• /
• 2014

A column solid phase extraction procedure based on modified polyurethane foam (PUF) by a newly synthesized Schiff base ionophore, named 2,2'-{iminobis[propane-3,1-diylnitrilo(1E)prop-1-yl-1-ylidene]}diphenol, was developed for preconcentration step of trace amounts determination of copper ions in water samples by atomic absorption flame spectroscopy. The influence of parameters on the adsorption process such as sample pH, amount of modified PUF packed in the column, type and volume of stripping reagent and its flow rate were investigated and optimized. Under optimum experimental conditions, the calibration graph was linear in a relatively wide range ($0.005-210{\mu}g/ml$) with a limit of detection $0.002{\mu}g/ml$ of copper. The proposed method allows achieving to a concentration factor of >133. The capacity of a column (1.6 cm i.d.) packed by 6 g of PUF modified by 12 mg of the Schiff base was found to be $247.7({\pm}2.1){\mu}g$ of copper. It was found that the adsorption process was highly selective towards copper ions with respect to some associated metal ions. The presented procedure was successfully applied for determination of copper in some water samples.

• Fire Science and Engineering
• /
• v.27 no.3
• /
• pp.8-13
• /
• 2013

In case of fire in a high-rise building fire can be easily spread along the building external walls dramatically if the flame comes out through broken windows. There are a few effective methods to prevent the fire spread at the moment. One is using a fire resistance window, and the other is using a window sprinkler that discharges water to resist flame in case of fire. In this study a window sprinkler which is installed on top of windows and prevents fire by discharging water when its heat-responsive element opens was tested using a large scale furnace in accordance with the standard temperature-time graph. Test result showed that one window sprinkler was able to protect a 2,400 mm wide window from fire for 2 hours and the window backside's temperature locally increased up to $126^{\circ}C$ but kept stable around $100^{\circ}C$ for the test duration.