• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.3-10
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• 1982

This experiment was conducted to study the effect of soil water potenial on the growth and internal changes of stressed plants. The experimental imposition of soil water potential ( $\Psi$soil) were -0.1 to -0.2, -0.2 to -0.5, -0.5 to -3.0, -3.0 to -10.0 bar respectively. During water stress all growth rates were depressed, and the most sensitive period to water stress was found to be 10 to 25 days after transplanting. The water potential of leaf was declined rapidly within 12 hours after with holding of water. Nitrate reductase activity was decreased progressively as water deficit was built up in tobacco leaves, but the activity of alpha- amylase and super contents were increased. There were differences in peroxidase isozyme patterns between tile control and water stressed plant. New isozymes started to appear as tobacco leaf water potential decreased.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.772-778
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• 2015

Hydrolysis of isolate soybean protein (ISP) using subcritical water (SCW) was conducted to study the feasibility for producing protein hydrolyzate. SCW hydrolysis of SPI suspension (5-15%) was conducted in an electrically heated batch reactor (2 L). The effects of temperature (230 to $270^{\circ}C$) and holding time (10 to 50 min) on the degree of hydrolysis (DH) and the production of amino acids were studied by surface response method. The DH was determined by derivatizing the hydrolyzates with ortho-phthalaldehyde (OPA) solution. It was confirmed that reaction temperature and holding time affected the hydrothermolysis of soybean protein. However, the holding time was less effective on amino acid yield when the temperature was higher than $230^{\circ}C$. In order to achieve optimal yields of amino acids exceeding 43%, the temperature should be within the range between 256 and $268^{\circ}C$ with holding time from 29 to 41 min, respectively. A maximum estimated amino acid yield of 43.5% was obtained at $268^{\circ}C$ for 35 min.

• Horticultural Science & Technology
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• v.17 no.4
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• pp.481-484
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• 1999

This experiment was conducted to examine the effects of chitosan and sucrose on the vase life of cut rose (Rosa hybrida L. cv. Cardinal). Addition of 5 mg/L chitosan and 3% sucrose to the holding solution prolonged the vase life for 3 days as compared to the control, and improved quality of cut rose in flower diameter and fresh weight. Development of bent-neck was delayed by supply of 2 mg/L or 5 mg/L chitosan and 3% sucrose about 2 or 3 days. When 3% sucrose was added to the holding solution, the rate of water absorption more slowly decreased compared to the other treatments.

• Journal of Korea Foundry Society
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• v.13 no.5
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• pp.432-440
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• 1993

Ductile cast iron has a good ductility and toughness than those of gray cast iron, because the shape of graphite is spheroidal. Also, it has been reported that, additional strengthening and toughening of the ductile cast iron can be obtainded from the proper combination of matrix structures by the heat treatment and addition of alloying elements. In this study the effect of special heat treatment and addition of alloying elements(Ni, Mo) on the multi-phase(ferrite-bainite-martensite) structures, strength and toughness of ductile cast iron were studied systematically. In water quenching from $770^{\circ}C$, the martensite volume(%) increased, but the ferrite volume(%) decreased with increment of Ni content. In as cast, pearlite volume(%) and hardness increased with increment of Mo and Ni contents. And with the increment of the destabilization austempering holding time, the bainite volume(%) increased but the martensite volume(%) decreased. As destabilization austempering holding time is same, bainite volume(%) decreased, martensite increased with the increment of Ni and Mo contents. The hardness and tensile strength decreased, but impact energy increased with the decrease of Ni and Mo contents, and increment of holding time of destabilization austempering treatment.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.27-34
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• 1991

This study was carried out to investigate the use habit of drinking water. The survey data were collected from 1,282 of students and 175 of officers from September 1990 to June 1991 in Pusan city and the South of Kyung sang-do. The use rate of tap water among respondents was 33.5%, and the reasons that the others avoid using tap water were having the risk of heavy metals contamination and unsanitary. The 80% of respondents have drunk spring water or bottled water within two or three years. The keeping method of them were 53% in the refrigerator, and 33% in the indoor. The use rate of water vessels what were equipped in mineral springs was 85%. It's advisable that the picking of mineral water be cautious within two or three days after rain. The holding rate of water purifier in respondents was about 20%, and it was purchased within one or two years and the reliance degree of that in users was below 50%.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.265-271
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• 1992

Derivatives (microcrystalline chitin, carboxymethylchitin, acetylchitin, N-acetylchitosan, ethylchitosan and chitosansulfate) of chitin and chitosan were synthesized, and the physicochemical properties of the derivatives were compared with those of chitin and chitosan. Carboxymethylchitin was soluble in water or acetic acid, whereas chitosan and ethylchitosan were soluble in acetic acid alone. The water binding capacity of N-acetylchitosan was two fold higher than that of chitin. Lipid binding capacity of carboxymethylchitin was the highest, holding 1800%, and that of chitin was the lowest, holding 511% among the derivatives. Carboxymethylchitin among the derivatives showed the highest emulsifying capacity, however chitin and chitosan didn't produce emulsions. Dye binding capacity of acetylchitin was the highest, holding 0.93 mg dye/g sample (Blue R-250) and 0.96 mg dye/g sample (Red No. 2). It was concluded that carboxymethylchitin is a good emulsifier and N-acetylchitosan, chitosansulfate and chitosan are suitable for use as dye absorbents.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.597-603
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• 2014

In this study, the physicochemical and sensory quality characteristics due to the influence of various thawing methods on electro-magnetic and air blast frozen pork were examined. The packaged pork samples, which were frozen by air blast freezing at $-45^{\circ}C$ or electro-magnetic freezing at $-55^{\circ}C$, were thawed using 4 different methods: refrigeration ($4{\pm}1^{\circ}C$), room temperature (RT, $25^{\circ}C$), cold water ($15^{\circ}C$), and microwave (2450 MHz). Analyses were carried out to determine the drip and cooking loss, water holding capacity (WHC), moisture content and sensory evaluation. Frozen pork thawed in a microwave indicated relatively less thawing loss (0.63-1.24%) than the other thawing methods (0.68-1.38%). The cooking loss after electro-magnetic freezing indicated 37.4% by microwave thawing, compared with 32.9% by refrigeration, 36.5% by RT, and 37.2% by cold water in ham. The thawing of samples frozen by electro-magnetic freezing showed no significant differences between the methods used, while the moisture content was higher in belly thawed by microwave (62.0%) after electro-magnetic freezing than refrigeration (54.8%), RT (61.3%), and cold water (61.1%). The highest overall acceptability was shown for microwave thawing after electro-magnetic freezing but there were no significant differences compared to that of the other samples.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.30-34
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• 1988

In roastal fish farms the farmers, especialy engaging in dealing with the floating cage culture, going to know about relationships between holding capacity and water quality in cage. Some of water quality managers and specialists studing physiological ecology understand that the key of water quality management concerned fish farming is budget of dissolved oxygen. This paper deals with oxygen budget in floating cage of the yellow tail farms at southern coastal area in Korea. The sampling station is located at Konli-Do fish farm near Chungmu, and the data is collected for 24 hours from 3:00 p.m. 8th September 1987. In result, the needed oxygen coming after the consumption by the rearing fish had been supplied with the tide current exchange, the sum of oxygen produced by phytoplankton photosynthesis and diffused from atmosphere are no more that $43\%$ for the needs of sea water consumption included respiration of planktons and decomposition of organic matters. The optimum holding capacity of cage is possible to compute with the calculation of minimum diurnal water exchange rate $[Qin{\cdot}V^{-1}\;(C-\bar{c})]$ through net mesh of cage.

• Magazine of the Korean Society of Agricultural Engineers
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• v.62 no.4
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• pp.32-39
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• 2020

• Food Science and Preservation
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• v.19 no.2
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• pp.257-262
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• 2012

pasting characteristics. Their water contents, water holding capacities, solubilities, swelling power, amylose contents, damaged starches, particle sizes and pasting characteristics were measured. The water content and water holding capacities of various types of rice flours collected in the market were 7.64-14.97% and 95.22-232.94%, respectively. Their solubilities and swelling power were 1.97-37.40% and 1.33-5.76, respectively. Various types of rice flour had 32.11-305.67 ${\mu}m$ particle sizes. Among the various types of rice flour collected in the market, the lowest starch damaged content was 3.17%. The peak viscosities of the samples were 17.74-295.95 RVA. Among the rice flours that were collected in the market, the lowest pasting temperature was $69.72^{\circ}C$. As a result, it was shown that rice flour types with high starch damage contents tend to have higher expressed water holding capacities. Moreover, the samples with lower particle sizes tended to have final viscosities, and pasting temperatures.