• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.187-194
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• 2004

The surface flames in porous ceramic burner are experimentally characterized to investigate the effects of equivalence ratio and firing rates. The results show that the surface flames are classified into green, red radiant and blue surface flame as the decrease of equivalence ratio. And each flame is maintained very stable and represents the same flame characteristics at any orientation of ceramic burner. Particularly the blue surface flame is found to be very stable at very lean equivalence ratio at 7000kcal/hr to 20000kcal/hr firing rates. And the exhausted NOx was analysed to find out which flame has lower NOx emission. The blue surface flame shows the lowest NOx emission regardless of the location of burner since it sustains very stable at lean mixture ratio.

• Journal of the Korean Chemical Society
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• v.17 no.1
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• pp.40-46
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• 1973

The afterpolymerization of nylon 6 was carried out in three different reaction conditions, nitrogen flow, sealing and evacuation. The viscosity and reduced weight of polymer were increased by increasing the reaction time and temperature, and viscosity of polymers at constant reaction temperature was decreased as the following order: nitrogen flow >sealing >evacuation. The activation energy of afterpolymerization was 10.5 kcal/mole.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3003-3008
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• 2011

Reactions of benzyl alcohol and its derivatives by [Ru$^{IV}$(tpy)(dcbpy)(O)]$^{2+}$ (tpy = 2,2':6',2"-terpyridine; dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) leading to the corresponding benzaldehydes in acetonitrile and water have been studied. Kinetic studies show that the reaction is first-order in both alcohol and oxidant, with k = 1.65 (${\pm}$ 0.1) $M^{-1}s^{-1}$ at $20^{\circ}C$, ${\Delta}H^{\ddag}$ = 4.3 (${\pm}$ 0.1) kcal/mol, ${\Delta}S^{\ddag}$ = -22 (${\pm}$ 1) eu, and $E_a$ = 4.9 (${\pm}$ 0.1) kcal/mol. High ${\alpha}$ C-H kinetic isotope effects are observed, but O-H solvent isotope effects are negligible. Spectral evidences with the isotope effects suggest that oxidation of benzyl alcohols occurs by a two-electron, hydride transfer. The catalytic cycles of aerobic benzyl alcohol oxidation are employed.

• Journal of the Korean Ceramic Society
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• v.19 no.4
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• pp.309-315
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• 1982

$FeAl_2O_4$ was formed from the starting material of $Fe_2O_3$ and $Al_2O_3$ by controlling the oxygen partial pressure using $H_2-CO_2$ gas mixture, over the temperature range of 800~120$0^{\circ}C$. The formation mechanism of $FeAl_2O_4$ was found to be a second order chemical reaction, and the activation energy of formation was observed as 39.97 kcal/mole. Vaporization behavior of $FeAl_2O_4$ under $CO_2$ atmosphere was observed over the temperature range of 800~120$0^{\circ}C$. $FeAl_2O_4$ was vaporized by a second order chemical reaction and the activation energy was found to be 21.8kcal/mole. Electrical conductivity of $FeAl_2O_4$ was also measured.

• Journal of the Korean institute of surface engineering
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• v.28 no.2
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• pp.101-109
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• 1995

Electroetching rates of $FeCl_3$ solution were increased according to increasing solution temperature. Activation energy of electroetching at Be'36 and 5A/$dm^2$ condition was 28.3Kcal and also, at Be'46 and 5A/dm$^2$ condition was 33.2Kcal. At Be'36 concentration of $FeCl_3$ solution, electroetching rate were more higher than at Be'46 concentration. Surfaces of etched grooves obtained at 8A/$dm^2$ or higher current density in 46 Be' concentration of $FeCl_3$ solution were observed to be flat and smooth owing to suppressing chemical etching reaction. Distinctly etched boundaries became to be appeared at 2A/$dm^2$ in Be'41 electroetching condition by differential effects. In case of applying 8A/$dm^2$ current density to Be'46 of $FeCl_3$ solution, etching depth were 4 times and side etching were 6 times more than chemical etching case respectively.

• The Korean Journal of Ecology
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• v.13 no.3
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• pp.203-214
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• 1990

The work reported here aims to assess how Knots, Calidris canutus, accumulate rapidly large energy and nutrient reserve at Red Car in England. Most of Knots in England belong to long billed, long winged population compare with subspecies in Korea. The rate of prey intake of Knot increases as a nearest neighbour distance decreases. Foraging rate and vigilance rate increases as flock size decreases. The calorific value of each sized of Common Mussel Mytilus edulis, main food species of Knot, are almost same each other but the calorific content of each size Mussels are quite different each other. The rate of daily energy intake of Knots have been estimated from 192 kcal to 270 kcal.

• The Korean Journal of Food And Nutrition
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• v.6 no.2
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• pp.115-120
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• 1993

A nutrition survey of 80 high school students in urban dormitories, 17-19 year old, in Jeonbuk province was undertaken in August of 1990, to investigate dietary intake. Total energy intake of male and female was 2,246.0 and 1,584.9 kcal respectively. Energy Intakes from breakfast, lunch and dinner were 553.5, 683.4 and 1,023.0 kcal in male, and 372.9, 391.8 and 820.2 local in female. Protein daily intake of male and female was 95.3 and 62.9g, and carbohydrate intake was 368.1g and 259.6g respectively. Total energy intake of male student was composed of carbohydrate 65%. protein 16.8% and fat 18.2% and that of female was carbohydrate 65.5%, protein 15.9% and fat 18.6% respectively.

• Journal of environmental and Sanitary engineering
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• v.10 no.3
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• pp.29-34
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• 1995

This study was on the characteristics and heating values analysis of municipal solid wastes according to the volume- rate garbage collection system in Busan. Each waste sample was analyzed to obtain physical composition, proximate analysis, heating value, chemical composition. And the heating value were compared with those of the past waste collection system. The average physical composition of A.P.T. area was food waste 54.0~65.7% , while that of common residence was food waste 57.9~61.2% . The density of solid waste were largely different for site and the highest densities of waste was $399.6kg/m^{3}$ from Market. The low heating value of waste from residence site was 996.9kca1/kg~1, 238.1 kcal/kg which was lower than 1, 000kcal/kg~1, 800kca1/kg of the past wastes. These difference was mainly due to the difference of moisture content and the amount of vegetables.

• Journal of Energy Engineering
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• v.4 no.3
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• pp.379-386
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• 1995

0.5 T/D 용량의 슬러리를 이용한 분류층가스화기에서의 인도네시아 탄인 Roto탄을 이용한 가스화 실험을 통하여 개발된 가스화기의 성능과 석탄가스화 특성을 파악하였다. 200 mesh 이하로 분쇄된 미분탄을 62.5%(H2O/coal=0.6)로 물과 혼합된 슬러리를 0.5%의 유도화제와 화재의 20%의 CaO를 화재의 융점강하를 위하여 첨가시켰다. 화재의 융점이 1511$^{\circ}C$에서 130$0^{\circ}C$까지 떨어진 것이 관측되었다. 생성된 슬래그는 Quenching 부위에서 물에 의한 급랭으로 인한 열 충격으로 1~2 cm의 크기로 분쇄되었다. 실험결과 생성된 가스는 CO는 O2/coal의 비가 증가할수록 감소하였고, H2 및 CO2는 증가하는 것으로 관찰되었다. 생성된 가스의 발열량은 천연가스의(10,000 Kcal/Nm3)/약 1/8인 1700~1300 Kcal/Nm3로 측정되었다.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.40-46
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• 1994

In order to study the properties of cochineal color, variation of uv, visible spectra by pH, dyeing properties on the silk in several dyeing conditions and thermodynamic parameter were investigated. Cochineal colors had an unusual to pH, especially had instability in alkali condition. An increase in the dyeing temperature and in time resulted in an increase in the dye content of silk fibers. Concentration of cochineal color in the silk fiber was related to pH and the maximum exhaustion of cochineal colors showed at about pH 3. The value of apparent diffusion coefficients and standard affinities of dyeing increased with the increase of dyeing temperature. The standard heats of dyeing(ΔH°), variation of entropy(ΔS°) and activation energy(E/sub act/) were caculated to be -1.72kcal/mo1, -3.77cal/mo1ㆍdeg and 1.26kcal/mo1, respectively. Silk fabrics were dyed bright red by tin chloride, reddish purple by copper sulfate, and bluish gray by iron sulfate, respectively. Lightfastness of silk fabrics mordanted by metal ion was weak.