• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.478-484
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• 1997

In a recent paper[Bull. Kor. Chem. Soc. 17, 735 (1996)] we reported results of molecular dynamic (MD) simulations for the thermodynamic and structural properties of liquid n-alkanes, from n-butane to n-heptadecane, using three different models. Two of the three classes of models are collapsed atomic models while the third class is an atomistically detailed model. In the present paper we present results of MD simulations for the dynamic properties of liquid n-alkanes using the same models. The agreement of two self-diffusion coefficients of liquid n-alkanes calculated from the mean square displacements (MSD) via the Einstein equation and the velocity auto-correlation (VAC) functions via the Green-Kubo relation is excellent. The viscosities of n-butane to n-nonane calculated from the stress auto-correlation (SAC) functions and the thermal conductivities of n-pentane to n-decane calculated from the heat-flux auto-correlation (HFAC) functions via the Green-Kubo relations are smaller than the experimental values by approximately a factor of 2 and 4, respectively.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.1
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• pp.35-42
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• 2009

In this study, a spark ignition engine operated with LPG and DME blended fuel was studied experimentally. The effect of n-butane and propane on performance and emissions of a SI engine fuelled by LPG/DME blended fuel were examined. Stable engine operation was achieved for a wide range of engine loads with propane containing LPG/DME blended fuel compare to butane containing LPG/DME blended fuel since octane number of propane was much higher than that of butane. Also, engine output operated with propane containing blended fuel was comparable to pure LPG fuel operation. Engine output power was decreased and break specific fuel consumption (BSFC) was increased with the blended fuel since the energy content of DME was much lower than that of LPG. Considering the results of engine output power, bsfc, and exhaust emissions, the propane containing LPG/DME blended fuel could be used as an alternative fuel for LPG.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.9
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• pp.816-823
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• 2005

This paper deals with the heat exchange performance prediction of a counter flow type double-tube condenser for natural refrigerant mixtures composed of Propane/n-Butane or Propane/i-Butane in a smooth tube and a micro-fin tube. The local characteristics of heat transfer, mass transfer and pressure drop are calculated using a prediction method developed by the authors. The total pressure drop and the overall heat transfer coefficient are also evaluated on various heat exchange conditions. The calculated results of the natural refrigerant mixtures are compared with HCFC22. In conclusion, natural refrigerant mixtures composed of Propane/n-Butane or Propane/i-Butane are appropriate candidates for alternative refrigerant from the viewpoint of heat transfer characteristics.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.11 s.254
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• pp.1123-1130
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• 2006

This study discusses about research efforts of hydrogen generation from hydrocarbon(e.g., diesel, gasoline, natural gas, and LPG), especially, butane reforming by using Autothermal Reforming Reaction (ATR) technology. Several catalysts were selected for butane ATR. Thermodynamic reactor conditions (temperature, $O_2$/C, S/C) are varied and reforming characteristics of 2 catalysts (Pt and Rh on ceramic supports) and 1 commercial catalyst (FCR-HC35) have been examined. To understand reaction behaviors in an ATR reactor comprehensively, temperature profiles of reactor were observed. By mass transfer limitation, fuel conversion decreases when GHSV increases. Significant temperature variation along the reactor was observed and it was mainly due reaction kinetics difference between exothermic oxidation and endothermic reforming reaction.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.9-12
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• 2008

The internal reforming of n-Butane on Ni-YSZ and Cu-Ceria-YSZ was investigated with anode granule at steam to carbon ratio from 0 to 3 and at temperature of $750^{\circ}C$. Although hydrogen production was lager at Ni-YSZ, resistivity for carbon deposition was better at Cu-Ceria-YSZ. These phenomena occur because unwanted side reaction go on with reforming reaction for hydrogen production at Ni-YSZ.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.364-369
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• 2013

Oxidative dehydrogenation of n-butane over mesoporous Cr catalysts were studied. Catalysts were prepared by Cr impregnated method over Ti or Zr dispersed mesoporous support such as SBA-15, ${\gamma}$-alumina and characterized by XRD, SEM, TEM, FT-IR UV-Vis and ICP-AES. The effect of high surface area was not noticed appreciably in terms of conversion, but for Cr catalysts with Ti and Zr-incorporated on SBA-15 and ${\gamma}$-alumina. showed high selectivity of trans-2-butene.

• YAKHAK HOEJI
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• v.53 no.3
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• pp.161-164
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• 2009

Synthetic studies directed toward an asymmetric total synthesis of calycotomine, an representative tetrahydroisoquinoline, are described. The application of N-tert-butane sulfinyl chiral auxiliary to the Pictet-Spengler type reaction for the efficient synthesis of tetrahydroisoquinoline skeleton has been also investigated.

• Bulletin of the Korean Chemical Society
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• v.3 no.1
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• pp.1-4
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• 1982

A quantitative treatment of ${\pi}$-nonbonded and $n-{\sigma}^{\ast}$ interactions and through-bond coupling effect was attempted using n-butane, n-butyl radical, and tetramethylene diradical. Results of STO-3G level calculations showed that: (1) conformational preferences can be predicted quantitatively based solely on the additive effect of ${\pi}$-nonbonded and $n-{\sigma}^{\ast}$ interactions, the predominant effect being the ${\pi}$-nonbonded interactions, (2) $(n-{\sigma}^{\ast})_{anti}$ is destabilizing whereas $(n-{\sigma}^{\ast})_{syn}$ is weakly stabilizing, which are contrary to what we expect from the normal $n-{\sigma}^{\ast}$ interaction, (3) througb-bond coupling of the two radical lobes is destabilizing for the triplet but stabilizing for the singlet tetramethylene diradical.

• Bulletin of the Korean Chemical Society
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• v.20 no.4
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• pp.459-462
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• 1999

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.2
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• pp.102-106
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• 2016

An experimental study on the flow characteristics under various laminar coflow diffusion flames was conducted with a particular focus on the buoyancy force exerted from gaseous hydrocarbon fuels. Methane ($CH_4$), ethylene ($C_2H_4$), and n-butane ($C_4H_{10}$) were used as the fuels. A coflow burner and the Schlieren imaging technique were used to observe the flow field of each fuel near the nozzle exit as well as the flow characteristics in the flames. The results show that a vortex with a density heavier than air appeared in n-butane near the nozzle exit with a strong negative buoyancy on the fuel steam. As the Reynolds number increased through the control of the fuel velocity of the n-butane flame, the vortices were greater and the vortex tips were moved up from the nozzle exit. In addition, the heated nozzle affected the flow fields of the fuel steam near the nozzle exit.