• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.379-385
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• 1983

Forage productivity of Job's tears (Coix lachryma-jobi L.) and adlay (C. lachryma-jobi var. mayuen (ROMAN.) STAPF) and a hybrid corn (Kwangog) and sorghum-sudangrass hybrid (Pioneer 988) was compared in the southern part of Korea where black streaked dwarf virus' (BSDV) is prevalent. Emergence of Job's tears and adlay was more delayed compared to a corn or sorghum-sudangrass hybrid under the drought field conditions. Early growth and regrowth of Job's tears and adlay were less than those of sorghum-sudangrass hybrid. Fresh weight, dry weight, and digestible dry matter of Job's tears and adlay cut once approximately 40 days after flowering were much higher than those of two cuts at every flowering stage. Dry weight of one-cut Job's tears and ad lay harvested 40 days after flowering was similar to the total dry weight of three-cut sorghum-sudangrass hybrid but higher than that of silage corn. Digestible dry matter production was greater in the order of sorghum-sudangrass, corn, one-cut and two-cut Job's tears and adlay. Corn was severely infected with BSDV, but digestible dry matter was relatively high due to its higher in vitro dry matter digestibility. Among the Job's tears and adlay varieties, a variety of Job's tears with globular fruit shape was best for forage production due to its taller plant height, thick stem, wider leaf blades, higher leaf blade/total dry weight ratio, and higher forage yield. However, hulled grain yield of ad lay varieties was higher than that of Job's tears due to a higher hulled/rough grain ratio although they had similar rough grain yields.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.3
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• pp.241-247
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• 2020

Sesame is typically a temperature- and day length-sensitive plant, as its flowering is promoted under high temperature and shorter day length conditions. The experiment carried out in the present study revealed that day length influenced sesame flowering to a much greater extent than temperature. The degree of day length influence differed depending on the sesame variety. Days from sowing to flowering was negatively correlated with yield-related characteristics such as stem length, capsule number per plant, 1,000 seed weight, and seed weight per 10a. In cases where the period from sowing to flowering was longer and flowering date was later, the reproductive growth period was shorter during maturity. Analysis of the effects of temperature and day length on seed yield production revealed that temperature was a much more influential factor than day length. However, day length was more influential than temperature under low temperatures, such as 22℃. All varieties apart from Ansan were shown to be primarily influenced by temperature. Sesame varieties were grouped in view of optimal seed sowing time through principal components analysis. The Poongsung and Sungboon varieties favored early sowing under low temperatures and short day lengths. The DT45, Poongsung, 90 days, Ansan, and Sungboon varieties favored late sowing under high temperatures and long day lengths. The Yangbaek and Arum varieties could be sown both early and late.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.22-27
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• 2006

This study was carried out to determine the optimum conditions for making soybean curd(or tofu) from defatted soybean flour.. Heating soymilk above $80^{\circ}C$ for at least $5{\sim}10\;min$ was necessary for soybean protein to form aggregates during subsequent coagulation process with glucono-${\delta}$-lactone(GDL). For maximum yield of tofu, with water content of approximately 80%, extra addition of 20 g of oil and 5 g of GDL per 425 g of soybean flour was needed. Maintaining soymilk temperature around $75^{\circ}C$ for 5 min was necessary when GDL was used as the coagulant.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.240-246
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• 1992

Preparation of soybean oil fatty acid methyl esters (soybean oil FAME) through the transesterification of soybean oil with alkaline catalyst was optimized in terms of contents of residual free fatty acids (FFA) in soybean oil FAME and yield of soybean oil FAME due to the inhibitory effect of FFA on sucrose polyesters synthesis. Soybean oil FAME and residual FFA were analyzed quantitatively by simultaneous gas chromatography on a fused silica capillary column after converting the FFA in soybean oil FAME to tert.-butyldimethylsilyl (TBDMS) derivatives. Transesterification of soybean oil was successfully performed with alkaline catalyst (NaOH, 95%), which resulted in 99.1% yield of soybean oil FAME and less than 0.1% residual FFA contents under the conditions such as $30^{\circ}C$, 20min. and 6:1 molar ratio of anhydrous methanol to soybean oil.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.203-209
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• 1983

The occurrence and regional distribution of low temperature and drought during rice cropping period in Korea were studied to characterize the climatic impacts. The long term changes in rice yield, air temperature and precipitation were analyzed, and regional distributions were characterized. The significant climatic impacts on rice yield were heavy rain or flood, drought and low temperature. Since 1910, the occurrence of drought was 29 times, that of flood was 24 times and that of low temperature was 9 times; however, the drought and flood damages were decreased due to expansion of irrigation system since 1970 but low temperature damage was remarkedly increased. The long term changes in air temperature since 1908 in Suweon showed that the 5-year moving average from July to August decreased while that from May to June increased. The occurrence probability of the long term and early term low temperature types were the greatest in Korea and were in order of Suweon, Daegu and Kwangiu. The long term changes in 10-year moving average precipitation from April to June showed a 15 year cycle and recent years were in low precipitation period. The drought frequencies were the highest in Daegu and Pohang area. According to the precipitation from April to June and resevtoir storage at late June, the severest dry area were the Youngnam inland and the southwest coastal area.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.529-539
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• 2010

In order to evaluate the effect of soil salinity and culturing conditions including compost application and vinyl mulching on the maintenance of ridge and the growth of upland crops, three crops such as corn, soybean and sweet potato were experimented by using three or four cultivars of crops in the Saemangeum reclaimed tidal land. Average soil salinity before seeding was 2 dS $m^{-1}$, which was low enough for general upland crops to grow. However, high soil EC more than 16 dS $m^{-1}$ was observed in some parts of the experimented field. In the experiment, it was concluded that growth retardation and yield reduction of summer upland crops might be from severe erosion of ridge, soil compaction, flooding or wet soil condition and high salinity of some parts, and then these deteriorations were possibly improved for good crop growth and yield increase by compost application and vinyl mulching cultivation in the Saemangeum reclaimed tidal land.

• Korean Journal of Weed Science
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• v.11 no.1
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• pp.3-10
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• 1991

Several rice herbicides were evaluated to determine the herbicidal efficacy on dry seeded paddy rice. The time of herbicide application was within 1 day after seeding(DAS), 18 DAS, and 40 DAS. Under the upland conditions 30 DAS(before permanent flooding) dominant weed species were Echinochloa sp., Digitaria sp., Leptochla sp., weedy rice and other several annual broadleaved weeds belonging to Cruciferae, but after flooding Echinochloa sp., Aeschynomene sp., Eleocharis kuroguwai, Cyperus sorotinus, Ludwigia prostrata, Aneilema japonica were dominat. Early application (1 DAS) of thiobencarb, pyrazolate/butachlor, or chlomethoxyfen/butachlor resulted in very good herbicidal efficacy only during the first 30 days, but not thereafter. Application of propanil+butachlor on 18 DAS did not control the late occurring weeds effectively. Application of bentazone/quinchlorac on 40 DAS successfully suppressed weed growth throughout the remaining rice growing season and showed similar grain yield as hand weeded plot. Weed growth reduced the plant height, panicle number, 1000-grain weight, percent ripened grains, and grain yield of rice by 7, 82, 19, 55 and 87% respectively. There was a positive linear relationship between weed weight and lodging index of rice.

• Korean Journal of Materials Research
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• v.11 no.7
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• pp.580-584
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• 2001

We have investigated the deposition characteristics of Ti-Si-N films obtained by rf magnetron sputtering with ratios of Ti/Si targets in an $Ar/N_2$ gas mixture. The growth rate and stoichiometry dependence of the Ti-Si-N films on the ratio of Ti/Si and $N_2$ flow rate ratio were found to be due to the different nitriding rate of Ti and Si targets. Additionally, their different sputtering yield of nitrified Ti and Si make a reason as well. Lowering Si content in the film favored the formation of crystalline TiN, leading to the low resistivity. Increasing N content led to the Ti-Si-N films having a higher density and compressive stress, suggesting that the N content in the film is one of the most important factors determining the diffusion barrier characteristics. In the current work, the optimum process conditions for the formation of efficient diffusion barrier of Ti-Si-N film has successfully obtained by manipulating the Ti/Si ratio of target and $N_2$ flow rate ratio.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.99-106
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• 1998

Two kinds of carrageenan were extracted from red seaweeds, Tichocarpus crinitus, collected in The Peter the Great Bay of Russia on August, 1996. One is KC1-insoluble carrageenan and another is KC1-soluble carrageenan. The yield of KC1-insoluble carrageenan was 17.15%, which is composed of 18.06% total sulfate, 5.61% protein, 3.51% K+, 0.49% Na+, 1.66% Ca2+, 54.26% galactose, 4.68% xylose, trace of mannose and glucose. The yield of KC1-soluble carrageenan was 3.52%, which is composed of 24.06% total sulfate, 5.2% protein, 5.32% K+, 0.16% Na+, 2.80% Ca2+, 33.54% galactose, 5.48% xylose, 4.32% mannose, trace of glucose. But rhamnose was not detected in both case. FT-IR spectrum showed that the KC1-insoluble carrageenan was kappa-type carrageenan and that KC1-soluble carrageenan was lambda, iota hybrid-type carrageenan. KC1-insoluble carrageenan was very weakly formation the gel compared with KC1-insoluble carrageenan from other red seaweeds. So we investigated viscosity. Both type carrageenan was stable in the temperature until 9$0^{\circ}C$, 1 hr. The viscosity of the solution of KC1-insoluble carrageenan was increased to about two folds by K+, but was not changed by Ca2+. The viscosity of the solution of KC1-soluble carrageenan was reduced by K+ and Ca2+. Both of them was stabilized in alkali but was reduced in comparison with acid conditions. In this study, both carrageenan was expected as thickening agent than gelling agent for food additives.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.99-103
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• 2002

The suitable sterilization conditions in pot cultivation of varieties of Chunchunutari-2-ho and Suhannutari-1-ho Pleurotus ostreatus were investigated. The substrate formulations for the cultivation consisted of 40% poplar sawdust, 40% waste cotton and 20% beet pulp (PWB), and 40% poplar sawdust, 40% cotton seed hull and 20% beet pulp (PCB). The increase in the sterilization temperature caused decrease in the pH of the substrate. The moisture content of PWB substrate increased by 1.8%, but that of PCB substrate decreased by 4.1 % after low temperature sterilization ($12hr\;at\;60^{\circ}C$). However, a little change in the sterilization at higher temperature ($6hr\;at\;100^{\circ}C\;and\;90min\;at\;121^{\circ}C$) did not alter the moisture content of both substrate appreciably. The duration of mycelial growth was longest and its density was lowest in low temperature sterilization ($12hr\;at\;60^{\circ}C$). The high pressure sterilization ($90min\;at\;121^{\circ}C$) of PCB substrate produced high yield (236.6 g/pot) and the highest biological efficiency (96.6%) for Chunchunutari-2-ho. On the contrary the high temperatures sterilization ($6hr\;at\;100^{\circ}C$) of PCB substrate resulted in the yield of 259.1 g/pot with the biological efficiency 94.9% for Suhannutari-2-ho.