• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.195-199
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• 2010

This experiment was conducted to develop optimum sesame cultivation practices as succeeding cropping system of watermelon in the greenhouse condition. We also compared major components in sesame seed cultivated in the greenhouse and open field condition. The adaptable varieties under the greenhouse condition were white sesame 'Pyoungan' and black sesame 'Jinki' which showed higher yield and disease resistance. We also conducted several experiments to determine optimum sowing date, planting density and pinching time. Grain yields were statistically different according to the several sowing dates. In general, sesame sowing on June 30th showed higher grain yields than July 10th, July 20th and July 30th in the greenhouse. We also found out sesame cultivation practice with the row spacing of 40 cm and interplant spacing of 30 cm (a few branch type) or 40 cm (many branch type) showed higher yield than other treatments. Optimum pinching time was 25 days after first flowering in main stem when thousand seed weight and grain yield were highest. In the comparison of major components of sesame at the different cultivation conditions, sesame seeds cultivated in the greenhouse contained 4% much more oil content than open field condition. The lignan compounds, sesamin and sesamolin were also higher by 6% in the greenhouse than open field condition. It was concluded that sesame cultivation practices as succeeding cropping system of watermelon in the greenhouse condition guaranteed higher grain yield with less labor input which is now emerging alternative farming practice system in present aging rural society and will also give sesame cultivation farmers to increase net income in Korea.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.565-571
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• 2007

This study was carried out to investigate an optimum condition for the high angiotensin-l converting enzyme (ACE) inhibitory activity and the yield on enzyme concentration, casein concentration, and hydrolysis time. The optimum condition was performed by response surface methodology for acquirement of casein hydrolysate of milk which shows high ACE inhibitory activity, Among 8 tested enzymes, Protamex showed the highest activation degree with 77.03 unit/g from casein. Their hydrolysis degrees of flovourzyme 500MG, protamex, mixture from 1% casein were 85.5, 88.5, and 93.5%, respectively. The ranges of enzyme concentration (0.25-1.25%), casein concentration (2.5-12.5%), and hydrolysis time (20-100 min) as 3 independent variables through preliminary experiments of the yield of casein hydrolysate and ACE inhibitory activity, and it shows optimum response surface at a saddle point. It shows enzyme concentration (0.64%), casein concentration (8.38%), and hydrolysis time (55.81 min) in the yield aspect and showed the highest activity at enzyme concentration (0.86%), casein concentration (5.97%), and hydrolysis time (63.86 min) in ACE inhibitory aspect. The $R^2$ value of a fitted optimum formula on the hydrolysis yield was 0.9751 as the significant level of 1%. The $R^2$ value of a fitted optimum formula on ACE inhibitory activity is 0.8398, and the significance is recognized in the range of 5%.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.522-530
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• 2019

Two edible plants, Allium victorialis var. platyphyllum and Ligularia stenocephala, and one medicinal plant, Panax ginseng, were cultivated in the understory of an artificial Larix kaempferi plantation for ten years. Growth characteristics (number of leaves and flower stalks per plant, and leaf length and width), survival rate, and yield (fresh weight of plants) per unit area (1 ㎡) were investigated one year after planting, and six and ten years following cultivation. P. ginseng and L. stenocephala survived at a high percentage for two years after planting. Results showed that P. ginseng had longer and thicker roots when aged; however, a large number of plants died and the yield was low. In contrast, almost half of A. victorialis var. platyphyllum died within two years of planting. The surviving plants grew well for ten years and the yield was increased. The leaf length and width of L. stenocephala increased; however, the survival rate and the number of leaves per plant decreased as the period of cultivation was extended. In contrast, A. victorialis var. platyphyllum survived at a lower rate (50%) than the two other crops (98% for L. stenocephala and 83% for P. ginseng) during the early cultivation period, with little change in the survival rate over an extended time; however, the yields increased. This species showed an increase in the number of flower stalks and leaves, and as a result, the larger leaves increased the yield. We evaluated the understory cultivation of three crops in a L. kaempferi plantation under natural conditions, with no irrigation or fertilization, and Allium victorialis var. platyphyllum showed the greatest growth potential among the three tested crops.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.732-738
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• 2011

Effect of metal oxide catalysts and ionic liquids on the synthesis of methyl carbamate(MC) and dimethyl carbonate (DMC) from urea and methanol was investigated in a high pressure reaction system. In closed system, MC yield from urea and methanol reached almost 100% at reaction temperature over $150^{\circ}C$ without catalyst, whereas DMC yield of 1.5% under was obtained irrespective of catalysts used. In DMC synthesis from MC and methanol, $ZnCl_{2}$ showed the highest catalytic activity and led to the DMC yield of 16.3% under optimal conditions. Furthermore, DMC yield can be enhanced by the simultaneous application of ionic liquids with nano-sized catalysts in semi-continuous reaction system.

• Journal of the Korean Chemical Society
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• v.21 no.3
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• pp.180-186
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• 1977

The preparation of 1-chloro-2-iodoperfluorocycloalkenes was achieved with a short reaction time and a high yield when the starting compound was iodinated via the metalation process using an alkyllithium reagent. Especially, the high yield of 1-chloro-2-iodo-perfluorocyclohexene was obtained when 1,2-dichloroperfluorocyclohexene was iodinated via the same reaction conditions. The coupling reaction of 1,2-dihaloperfluorocycloalkenes was also achieved with a lower reaction temperature and a shorter reaction time when the equal slurry mixture of fluorocycloolefines and DMF was reacted at a high pressure in a sublimer. The yield of the coupling product was greatly improved by this process. For a typical example, the coupling reaction of the 1-chloro-2-iodotetrafluorocyclobutene was proceeded with a higher yield of the product than that of the reported reaction, when the present method was adopted. A plausible reaction mechanism of the present coupling reactiont was proposed and the physical characteristics of the coupling product were confirmed.

• Korean Journal of Medicinal Crop Science
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• v.17 no.6
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• pp.458-463
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• 2009

This study was conducted to find out some conditions for optimum cultivation of Angelica gigas Nakai by the investigation of root yield and decursin content from different seeding sizes and accumulative temperature. Accumulative temperature from April to October was $4,309^{\circ}C$ on altitude 100 m, $4,242^{\circ}C$ on 250 m, $3,662^{\circ}C$ on 530 m, $3,435^{\circ}C$ on 730 m, and altitude 530~730 m was less $650{\sim}870^{\circ}C$ than altitude 100 m cultivation areas of A. gigas. Seedling stand rate was increased from 86.4% to more than 90% as accumulative temperature decreases, and was increased in above 7 mm of seedling size, and 10% in non-mulching more than PE film mulching. Yield was increased as accumulative temperature decreases and in PE film mulching as 310.2 kg/10a. Also, Yield was increased in 7~9 mm than seedling diameter 5~7 mm as 313.0 kg/10a. Decursin content of primary roots was increased as altitude rises, ie, as 2.55% on altitude 100 m, 3.33% on 250 m, 5.51% on 530 m, and 6.24% on 730 m. Decursinol angelate content appeared little than decursin content as 1.08% on altitude 100 m, 1.37% on 250 m, 1.99% on 530 m, 2.38% on 730 m, and as altitude was heightened, content was increased.

• Journal of Hydrogen and New Energy
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• v.26 no.5
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• pp.477-483
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• 2015

LFG (Land-Fill Gas) includes components of $CH_4$, $CO_2$, $O_2$, $N_2$, and water. The preparation of synthesis gas from LFG as a DME (Dimethyl Ether) feedstock was studied by methane reforming of $CO_2$, $O_2$ and steam over $NiO-MgO-CeO_2/Al_2O_3$ catalyst. Our experiments were performed to investigate the effects of methane conversion and syngas yield on the amount of LFG components over $NiO-MgO-CeO_2/Al_2O_3$ catalyst. Results were obtained through the methan reforming experiments at the temperature of $900^{\circ}C$ and GHSV of 8,800. The results were as following; it has generally shown that syngas yield increase with the increase of oxygen and steam amounts and then decrease. Highly methane conversion of above 98% and syngas yield of approximately 60% were obtained in the feed of gas composition flow-rate of 243ml/min of $CH_4$, 241ml/min of $CO_2$, 195ml/min of $O_2$, 48ml/min of $N_2$, and 450ml/min of steam, respectively, under reactor pressure of 1 bar for 200 hrs of reaction time. Also, it was shown that catalyst deactivation by coke formation was reduced by excessively adding oxygen and steam as an oxidizer of the methane reforming.

• Journal of Life Science
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• v.16 no.1
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• pp.1-5
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• 2006

This study investigated the optimal conditions of high yield production of cyclofructan (CF) using recombinant deletion mutant enzyme CFT108 which is constructed by N-terminal deletion from cycloinulooligosaccharide fructanotransferase (CFTase) gene of Penibacillus polymyxa. The production yield was dependent on reaction time, substrate concentration and enzyme concentration. The optimum reaction time for industrial purpose was achieved at 3 hr reaction. The optimal concentrations of substrate and enzyme were found to be $2\%$ inulin and 40 unit/ g inulin, respectively. At optimum condition, 9.5 g/l of maximum yield and $47.5\%$ of conversion efficacy were achieved. For purification of CF produced, the reaction mixture was treated with 1 unit/ml exoinulinase and then added $3\%$ CaO three times with blowing $CO_2$ gas, resulted in $95\%$ purity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.2
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• pp.104-112
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• 2016

A double-cropping system with soybean (Glycine max) following the cultivation of potato, garlic, and onion is widely adopted in the southern region of Korea. For this system, marginal dates for planting must be determined for profitable soybean yields, because the decision to plant soybean as a second crop is occasionally delayed by harvest of the first crop and weather conditions. In order to investigate the effect of planting date on soybean yield, three cultivars (early and late maturity) were planted on seven different dates from May 1 to July 30 in both paddy and upland fields across 2012 and 2013. Soybean yields were significantly different among the planting dates and the cultivars; however, the interaction between cultivar and planting date was not significant. Based on linear regression, the maximum yield of soybean was reached with a June 10 planting date, with a sharp decline in yield for crops planted after this date. The results of this study were consistent with those of a previous one that recommends early and mid-June as the optimum planting period. Regardless of soybean ecotype, a reduction in yield of greater than 20% occurred when soybean was planted after mid-July. Frost during soybean growth can reduce yields, and the late maturity cultivars planted on July 30 were damaged by frost before completing maturation and harvest; however, early maturity cultivars were safely harvested. For sufficient time to develop and reach profitable yields, the planting of soybean before mid-July is recommended.

• Journal of Crop Science and Biotechnology
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• v.11 no.3
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• pp.215-222
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• 2008

Multilocation trials on 36 rice(Oryza sativa) genotypes of 3 different maturity groups were conducted at four different locations of Orissa for 3 years and 30 ragi(Eleusine coracana) genotypes of 2 different maturity groups were evaluated in three environmental conditions for 3 years. Grain yield data were subjected to stability analysis following linear regression model to estimate adaptability and stability parameters, i.e. b, and $S^2d$ Stability of performance of genotypes was also estimated by two other stability parameters viz., ecovalence W and AMMI stability value ASV. The rice and ragi genotypes of different duration groups showed wide variation in their mean yield, b, $S^2d$, W and ASV parameters. Seeds of the 36 rice and 30 ragi genotypes were treated with 500 and 100 ppm aqueous solution of maleic hydrazide(MH) for 24 hours, respectively to study MH-sensitivity. Sensitivity of genotypes to MH treatment was estimated in terms of seedling growth inhibition index(SGI). The rice and ragi genotypes showed wide differences in their MH-sensitivity in terms of SGI. Relationship of MH-sensitivity of genotypes with their yielding ability, adaptability and stability of performance was tested by contingency $x^2$ test. Low sensitivity of rice and ragi genotypes to MH in terms of SGI appeared to be good indicators of high yielding ability of genotypes. Also, low and high MH-sensitivity of genotypes would be a good indicator of better adaptability to rich and poor environments, respectively, in ragi but not in rice. Low MH-sensitivity of genotypes could be the good indicator of stability of yield performance in rice but not in ragi.