• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.74-83
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• 1983

In order to examine the relationship of fruit abscission and ethylene evolution in 'Jojuro' and 'Imamuraaki' pear trees, the thinning chemicals, ${\beta}$-naphthalene acetic acid (NAA), O, O-dimethyl-O-(3-methyl-4 nitrophenyl) posphorothioate (MEP), 1-naphthyl N-methyl carbamate (carbaryl), and 2-chloroethyl phosphonic acid (ethephon) were applied. Concurrently the effect of calcium acetate on the control of fruit abscission were examined when calcium acetate was added to ethephon and carbaryl. 1. All the applied chemicals (MEP, NAA, carbaryl and ethephon) was effective to abscise fruits in 'Jojuro', and MEP and carbaryl in 'Imamuraaki's. 2. The application of ethephon increased the ethylene evolution but other chemicals did not increase it. 3. There were no significant differences in total sugar contents of fruits by MEP, NAA, carbaryl and ethephon treatments. 4. When the calcium acetate was added to the ethephon and carbaryl, the thinning effects were offsetted. 5. The rate of defoliation due to ethephon treatment was controlled by addition of calcium acetate at 0.1~0.25 M. It was clarified that fruit abscission induced by thinning chemicals except ethephon was not directly related to ethylene production and that degree of fruit thinning can be regulated by addition of calcium acetate to thinning chemicals.

• Korean Chemical Engineering Research
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• v.47 no.2
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• pp.243-247
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• 2009

This study is purposed to analyze thermodynamic properties on the hydrogen production by ethylene glycol steam reforming. Various reaction conditions of temperatures(300~1,600 K), feed compositions(steam/carbon= 0.5~4.5), and pressures(1~30 atm) were applied to investigate the effects of the reaction conditions on the thermodynamic properties of dimethyl ether steam reforming. An endothermic steam reforming competed with an exothermic water gas shift reaction and an exothermic methanation within the applied reaction condition. Hydrogen production was initiated at the temperature of 400 K and the production rate was promoted at temperatures exceeding 500 K. An increase of steam to carbon ratio(S/C) in feed mixture over 1.0 resulted in the increase of the water gas shift reaction, which lowered the formation of carbon monoxide. The maximum hydrogen yield with minimizing loss of thermodynamic conversion efficiency was achieved at the reaction conditions of a temperature of 900 K and a steam to carbon ratio of 3.0.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.792-796
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• 2000

The staking cultivation (SC) of oriental melon (Cucumis mela L. var. makuwa Mak.) produced more fruit yield than that of the conventional (creeping) growing. In the SC, preharvest fruit drop rate was high as 47.6% compared to 13.0% of the conventional cultivation. However, the foliar application of aminoethoxyvinylglycine (AVG, $100mg{\cdot}L^{-1}$) at 2 weeks after flowering (20 days before harvest) greatly reduced fruit drops up to 10.9% without causing any effects on ripening and quality of fruits . The AVG application markedly suppressed ethylene production in harvested fruits.

• Journal of agriculture & life science
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• v.44 no.1
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• pp.1-8
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• 2010

This study was conducted to investigate effect of low temperature and ripeness stages on fruit quality of chilli pepper (cv. Nockgwang) during storage at 5, 7, and $10^{\circ}C$. Fruits at three ripeness stages were selected based on uniform fruit size and three maturities on peel color: S1 (fully developed fruit just before the onset of ripening), S2 (fruits in the onset of color change), and S3 (fruits in completely red in color). Lower temperature attributed to increase fruit weight loss (WL) and WL was higher in S2 than the other ripeness stages. The highest respiration rate and ethylene production was found at S2 fruit while those of fruit in green and red showed similar and remained lower level during storage. Electrolyte leakage (EL) was higher as storage temperature decreased. After 28 d storage, EL rates of fruits at $5^{\circ}C$ were 43, 36, and 17% in S1, S2, and S3 while those at $10^{\circ}C$ were 17, 19, and 14%, respectively. These results show that chilli pepper fruits are tended to lose more water at lower temperature partially associated with increased EL. Thus, threshold storage temperature must be considered for avoiding chilling during storage and for extending the storage life of fresh pepper fruits.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.527-533
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• 2012

This study was carried out to investigate the effects of aminoethoxyvinylglycine (AVG) application and heat treatment on fruit quality of 'Fuji' apples during CA storage. AVG ($75mg{\cdot}L^{-1}$) was applied to 'Fuji' tree at 150 and 175 days after full bloom (DAFB) and the fruit were harvested at 185, 195, and 205 DAFB, respectively. Respiration rate and ethylene production of fruit applied with AVG were greatly reduced more than those in control. Flesh firmness and acidity of fruit applied with AVG were higher than those in control. Flesh browning occurred in all of the control fruit regardless of harvest date. However, AVG-treated fruits were free of flesh browning except for late harvested fruits. At 185 DAFB, 'Fuji' apples were harvested and prestorage heat treatment was done for 3 days at $38^{\circ}C$ and 6 hours at $46^{\circ}C$. Heat treatment at $38^{\circ}C$ and $46^{\circ}C$ prior to CA storage greatly reduced respiration rate and ethylene production. The incidence of flesh browning were 35%, 14%, and 5%, in control fruit, heating at $38^{\circ}C$ and $46^{\circ}C$, respectively. The titratable acidity was lower at heated apple than at controlled one.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.203-210
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• 2013

This study was conducted to investigate the optimum storage temperature and the effect of 1-methylcyclopropene (1-MCP) on the postharvest physiology and quality of plumcot (Prunus salicina Lindle. ${\times}$ Prunus armeniaca L.) 'Harmony' fruits. plumcot fruits were stored at 0, 5, 10, and $20^{\circ}C$, respectively, with three different ripeness stages grouped by skin color development. Furthermore, we treated $1{\mu}L{\cdot}L^{-1}$ 1-MCP was treated at $10^{\circ}C$ for 17 hours and stored at $10^{\circ}C$ for 12 days to evaluate the effectiveness for better shelf-life. The results indicated that lower storage temperature than room temperature effectively reduced the respiration rate with delaying quality changes. While, the fruits showed worse fruit taste than the fruits stored at 10 and $20^{\circ}C$. Reversely, the fruits stored at $20^{\circ}C$ showed more respiration rate and ethylene production. 1-MCP treatment effectively reduced the skin red color development, ethylene production, $CO_2$ and softening of plumcot 'Harmony' fruits. Overall data indicated that the optimum harvest time and storage temperature could be 30-50% red color and near $10^{\circ}C$. Postharvest 1-MCP application at the level of $1.0{\mu}L{\cdot}L^{-1}$ could maintain fruit quality well in plumcot fruits.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.51-57
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• 2007

This study examined the possibility on the dietary value and cryopreservation of the marine microalga, Isochrysis galbana. Four cryoprotectants, dimethyl sulfoxide (DMSO), ethylene glycol (EG), glycerol (Gly) and 1.2-propanedial (PD) were tested at the concentrations of 1.0, 1.5, 2.0, 2.5 and 3.0 M respectively. The highest survival rates were obtained with 1.5 and 2.0 M of four cryoprotectants yielding a survival rate of 80%. Cell concentration of $30\;{\times}\;10^4\;cell/ml$ at the initial point of the experiment was increased to $365\;{\times}\;10^4\;cell/ml$ in 1.5 M of dimethyl sulfoxide, $298\;{\times}\;10^4\;cell/ml$ in 1.5 M of ethylene glycol, $512\;{\times}\;10^4\;cell/ml$ in 1.5 M of glycerol, and $385\;{\times}\;10^4\;cell/ml$ in 1.5 M of 1.2-propanedial after five days, respectively. In dietary value experiment, survival rate and growth were not significantly different.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.406-411
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• 2011

This study was conducted to find out the effect of cut-off period (0 hour, 3 hours, 6 hours, 12 hours, and 24 hours) to supply nutrient solution for chicon forcing at that was predrying treatment on the storability of chicon. The cut-off treatment increased dry matter rate, respiration rate, and ethylene production rate. The dry matter rate of chicon increased, as the cut-off period increased, but the respiration rate and ethylene production rate of chicon was highest in 12 hours and 6 hours cut-off treatment, respectively, and then their rates decreased, as the cut-off period prolonged. The weight loss at cut-off 6 hours treatment was lower than other treatments during $10^{\circ}C$ storage temperature. The cut-off 6 hours treatment showed higher carbon dioxide and oxygen concentration in 10,000 cc/$m^2$/day/atm oxygen permeability film package during storage period than control and showed a little predrying effect but was not statistically significant. At $4^{th}$ day, the ethylene concentration reached higher than other storage day and after that decreased but was not statistically significant. The quality of chicon for 3 hours, 6 hours, 24 hours cut-off treatments on storability showed higher than other treatments, accordingly. The 6 hours cut-off treatment showed the inhibited effect of the degree of browning of chicon cutting plane. The effect of 6 hours cut-off treatment on storability of chicon showed proper predrying effect, reduced moisture loss and browning inhibition apparently during $10^{\circ}C$ storage.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.352-358
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• 2006

We investigated the mechanism on occurring of briny injury in four fruit species (apple, pear, grape, peach). Briny injury of apple, pear, peach, and grape was induced by the foliar splay of saline solutions. Browning symptom was initiated one hour after the spray of 3% NaCl in apple, pearl and peach trees. while two hour were needed for grape, but the latter developed the symptom faster than the formers. Foliar spray of 3% NaCl resulted in 4-fold increase in ethylene production 24 h after the spray, and the production was returned to early stage rate after 72 h. Ethylene production of control was nearly constant with slight decrease after 4 h. Browning and defoliation response to the spray of 3% NaCl on lower side were not different from the spray on both sides regardless of fruit species, while no injury symptoms occurred by the spiny on upper side. In saline damage for treated date, lateral bud was only germinated in apple at 30 July. A shoot apex was 100% grew in all fruit tree. In result for hormonal content of leaf and shoot apex, control was high t-zeatin content in leaf. However, IAA and ABA content was increasing in high saline concentration.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.139-144
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• 2012

A numerical simulation has been performed to investigate effects of toluene mixing on soot formation in pure ethylene opposed-flow nonpremixed flame. Mixture ratios of toluene were 3%, 5%, 10%, and 20%. Senkin code for 0-D simulation and oppdif code for 1-D simulation based on CHEMKIN III were utilized. 0-D results by senkin showed that concentrations of methyl radicals and benzene were increased with increasing toluene mixture ratio. This implied that the mixing of toluene in pure ethylene diffusion flame produces more PAHs and soot than those of pure ethylene flame. 1-D result of 10 % toluene reaction by oppdif code showed that production rate for H radical was a crucial factor for benzene formation. These results imply that methyl radical, benzene and H radical play a important role on soot formation in diffusion flames.