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Kim, Jung-Ju;Baek, Seung-Wook;Kim, Han-Seok;Choi, Joon-Won
- Transactions of the Korean Society of Mechanical Engineers B
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- v.26 no.11
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- pp.1503-1512
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- 2002
From the view of the environmental protection against the use of fossil fuels, a great of efforts have been exerted to find an alternative energy source. Hydrogen may become an alternative However the product species of the hydrogen flame is only $H_2O$, which emits only non-luminous radiation so the radiation from it is much smaller than that for a hydrocarbon flame. In this study, the authors designed and fabricated a laboratory scale test furnace to study thermal characteristics of hydrogen-air diffusion flame. In addition. the effects of addition of reacting as welt as non-reacting solid particles were experimentally investigated. Among the total heat flux to the wall, about 75 % was occupied by radiation while 25% by convection. When the aluminum oxide (Al$_2$O$_3$) particles were added, the radiative heat flux was reduced due to heat blockage effects. On the other hand, the total as well as the radiative heat flux was increased when the carbon particles were seeded, since the overall temperature increased. The effects of swirl and excess air ratio were also examined.
https://doi.org/10.3795/KSME-B.2002.26.11.1503 인용 PDF KSCI

Choi, Joon-Won;Baek, Seung-Wook;Kim, Jung-Ju;Kim, Han-Seok
- 한국연소학회:학술대회논문집
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- 2002.11a
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- pp.129-139
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- 2002
From the view of the environmental protection against the use of fossil fuels, a great of efforts have been exerted to find an alternative energy source. Hydrogen may become an alternative. However the product species of the hydrogen flame is only $H_2O$, which emits only non-luminous radiation so the radiation from it is much smaller than that for a hydrocarbon flame. In this study, the authors designed and fabricated a laboratory scale test furnace to study thermal characteristics of hydrogen-air diffusion flame. In addition, the effects of addition of reacting as well as non-reacting solid particles were experimentally investigated. Among the total heat flux to the wall, about 75% was occupied by radiation while 25 % by convection. When the aluminum oxide ($Al_2O_3$) particles were added, the radiative heat flux was reduced due to heat blockage effects. On the other hand, the total as well as the radiative heat flux was increased when the carbon particles were seeded, since the overall temperature increased. The effects of swirl and excess air ratio were also examined.
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Kang, Tae-Jin;Yang, Deok-Chun
- Plant Resources
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- v.6 no.2
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- pp.144-148
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- 2003
Germination efficiency, such as days to germination and conditions for the hybrid seeds, was tested after hybrid seeds were sown on the medium. Seeds were germinated from 67 to 126 days after seeding in all cross combinations, and germination condition was different among hybrid combinations. There was big difference on days to germination based on the different media, that is, days to germination in the hyponex medium was shorter than that in the Knudson C medium. Mutants such as MMS and NaN$_3$ were used to cause mutation. Germination occurred with 0.1 % NaN$_3$ and MMS. However, even though germination occurred in other treatments (0.01 % and 0.2% of NaN$_3$ and MMS), brownish phenomenon was intense, or did not proceed and got worse after 4-5 months of seeding. In addition, it was performed to choose appropriate medium for the growth of Cymbidium rhizome whose media adaptability is more different than other orchids. Different concentration of NAA and Kinetin was used. As a result, C. goeringii hybrid showed difference for the concentration of NAA and Kinetin combination.
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Kwon Byung-Sun;Kim Sang-Kon;Bang Jin-Ki;Choi Seung-Sun;Lim Jung-Mook;Choi Gab-Lim
- Plant Resources
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- v.8 no.3
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- pp.281-285
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- 2005
In order to select suitable fertilizer level and sowing rate of Dangyo $^{#8}$(hybrid) rapeseed at the southern area of Korea, two varieties of Naehanyuchae (Normal) and Dangyo $^{#8}$(hybrid) rapeseed currently grown for oil production by two fertilizer level with 10-8-8 kg/10a and 15-8-8 kg/10a and three sowing rate with 500 g/10a, 1,000g/10a and 1,500g/10a with relatively high yield was grown at the same condition yield and yield components were observed. Dangyo $^{#8}$(hybrid) rapeseed was superior to oil-eed rapeseed for yield at the 15-8-8 kg/10a of fertilizer and 1,500 g/10a of sowing rate. Fertilizer level, $N-P_{2}O_5-K_{2}O$ = 15-8-8 kg/10a and sowing rate, 1,500 g/10a showed somewhat higher value in two varieties of Naehanyuchae(Normal) and Dangyo $^{#8}$(hybrid).
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