• 한국화재소방학회논문지
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• 제29권6호
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• pp.13-19
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• 2015

이 연구에서는 인(P)-질소(N)의 첨가제로 처리된 리기다 소나무의 연소성을 시험하였다. 15 wt%의 인-질소 첨가제 수용액으로 리기다 소나무에 3회 붓칠하여 실온에서 건조시킨 후, 콘칼로리미터(ISO 5660-1)를 이용하여 연소성을 시험하였다. 그 결과, 인-질소 첨가제로 처리한 시험편은 피로인산/암모니움이온 첨가제로 처리한 시험편을 제외하고, 처리하지 않은 시험편에 비하여 착화시간이 90~148 s으로 길었다. 또 불꽃소멸시간은 556~633 s으로서 길게 측정되었다. 그러나 인-질소 첨가제로 처리한 시험편은 무처리 시험편에 비해 각각 12.5~43.4% 정도 높은 평균열방출률과 11.8~43.1% 정도 높은 총열방출률을 나타내었다. 특히, 인-질소 첨가제로 처리한 시험편의 유효연소열은 15.60~18.37MJ/kg으로서 순수 리기다 소나무 시험편에 비하여 2.9~17.5% 낮게 나타났다. 따라서 인-질소 첨가제로 처리한 시험편은 순수 리기다 소나무 시험편에 비하여 연소 억제성을 부분적으로 향상시켰다.

• 수산해양기술연구
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• 제55권4호
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• pp.411-418
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• 2019

In this study, to investigate the effect of physical and chemical properties of butanol on the engine performance and combustion characteristics, the coefficient of variations of IMEP (indicated mean effective pressure) and fuel conversion efficiency were obtained by measuring the combustion pressure and the fuel consumption quantity according to the engine load and the mixing ratio of diesel oil and butanol. In addition, the combustion pressure was analyzed to obtain the pressure increasing rate and heat release rate, and then the combustion temperature was calculated using a single zone combustion model. The experimental and analysis results of butanol blending oil were compared with the those of diesel oil under the similar operation conditions to determine the performance of the engine and combustion characteristics. As a result, the combustion stabilities of D.O. and butanol blending oil were good in this experimental range, and the indicated fuel conversion efficiency of butanol blending oil was slightly higher at low load but that of D.O. was higher above medium load. The premixed combustion period of D.O. was almost constant regardless of the load. As the load was lower and the butanol blending ratio was higher, the premixed combustion period of butanol blending oil was longer and the premixed combustion period was almost constant at high load regardless of butanol blending ratio. The average heat release rate was higher with increasing loads; especially as butanol blending ratio was increased at high load, the average heat release rate of butanol blending oil was higher than that of D.O. In addition, the calculated maximum. combustion temperature of butanol blending oil was higher than that of D.O. at all loads.

• International Journal of Automotive Technology
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• 제6권6호
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• pp.563-570
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• 2005

A numerical study of high pressure and temperature droplet vaporization and combustion is conducted by formulating one dimensional evaporation model and single-step chemical reaction in the mixture of hydrocarbon fuel and air. The ambient pressure ranged from atmospheric conditions to the supercritical conditions. In order to account for the real gas effect on fluid p-v-T properties in high pressure conditions, the modified Soave-Redlich-Kwong state equation is used in the evaluation of thermophysical properties. Some computational results are compared with Sato's experimental data for the validation of calculations in case of vaporization. The comparison between predictions and experiments showed quite a good agreement. Droplet surface temperature increased with increasing pressure. Ignition time increased with increasing initial droplet diameter. Temporal or spatial distribution of mass fraction, mass diffusivity, Lewis number, thermal conductivity, and specific heat were presented.

• 한국분말재료학회지
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• 제15권4호
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• pp.279-284
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• 2008

Dense nanostructured $NbSi_2$ was synthesized by high-frequency induction-heated combustion synthesis (HFIHCS) method within 1 minute in one step from mechanically activated Nb and Si powders. Highly dense $NbSi_2$ with relative density of up to 99% was simultaneously synthesized and consolidated under the combined effects of an induced current and mechanical pressure of 60 MPa. The average grain size and mechanical properties (hardness and fracture toughness) of the compound were investigated.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.765-769
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• 2001

The refuse-derived fuel(RDF) is manufactured using waste plastics-based materials and its physical and chemical properties are analyzed. The manufacturing process consists of hand picking, primary magnetic separation, crushing, secondary magnetic separation, feeding and extrusion. The RDF products have a higher calorie content of over 6, 000 ㎉/kg and high stability because the waste plastics and paper are mainly selected. The combustion flue gas of RDF products is satisfied with the emission criteria of incinerator. The heavy metal concentration of combustion byproduct from the RDF boiler is also satisfied with the criteria and appears to be lower concentration than that of a common municipal waste incinerator.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.831-834
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• 2002

A novel ceramic synthesis technique, combustion synthesis, is explored to produce an orange-emitting $SnO_2:Eu^{3+}$ phosphors. This technique involves a reaction of metal salts with a citric acid as an organic fuel. The variation of the ratio of citric acid to metal introduces change in reaction temperature and atmosphere of the combustion reaction, which in turn influences crystallinity and luminescence properties of the final products significantly. And the heat treatment of the as-synthesized product improved the CL intensity of the products. Especially, the sample treated at above 1100 $^{\circ}C$ shows an orange-emission, which is attributed to the formation of single phase and well-crystallized $SnO_2$:Eu in rutile structure.

• 한국응용과학기술학회지
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• 제27권4호
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• pp.399-406
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• 2010

This study was performed to test the flame retardancy of zelkova sarrata-based materials by the treatment of ammonium salts. Zelkova sarrata plate was soaked by the treatment with three 20 wt% ammonium salt solutions consisting ammonium chloride (AMSL), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP), respectively, at the room temperature. After the drying specimen treated with chemicals, combustion properties were examined by the cone calorimeter (ISO 5660-1). When the ammonium salts were used as the retardant for zelkova sarrata, the flame retardancy improved due to the treated ammonium salts in the virgin zelkova sarrata. However the specimen shows increasing CO over virgin zelkova sarrata and It is supposed that toxicities depend on extents. Also, the specimen with ammonium salts showed the higher total smoke release (TSR) than that of virgin plate. Of specimens treated with ammonium salts the ammonium chloride handled the test side was considered a improved inhibitory effect of combustion.

• Transactions on Electrical and Electronic Materials
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• 제5권1호
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• pp.29-33
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• 2004

The materials showing high structure dispersity have been developed on the quartz base by mechano-chemical technology. Depending on the processing conditions and subsequent applications, the materials produced by mechano-chemical reaction (MCR) showed concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segneto-magnetics, contained a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds was synthesized having thickness up to 10∼50 nm and showing magnetic properties and etc.

• 한국세라믹학회지
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• 제34권3호
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• pp.273-273
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• 1997

• International Journal of Aeronautical and Space Sciences
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• 제17권3호
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• pp.358-365
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• 2016

In this study, one-dimensional analysis under the assumption of an inviscid flow was conducted for the experiment initiated by the French-German Research Institute of Saint-Louis (ISL) in order to investigate the energy effect of aluminum combustion. Previous theoretical analysis based on the assumptions of isentropic compression and a constant specific heat derived by ISL claimed that the experiment was not affected by the heat of aluminum combustion. However, rigorous analysis in present investigation that considered the average properties behind the shock wave compression and temperature-dependent specific heat showed that the S225 experiment was partially affected by the aluminum combustion. The increase in heat due to aluminum combustion was estimated from the rigorous analysis.