• Applied Biological Chemistry
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• v.13 no.1
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• pp.29-34
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• 1970

In order to prepare digested Protein source for the Weanling Food from soybean, an attempt was made to decompose steamed soybean protein to amino acids and peptides by protease and cellulase produced from Aspergillus niger and Aspergillus sojae. In this paper, the optimum condition for digestion of soybean protein were studied and also investigated the effects of decolorization of it. As the results, followings were obtained; 1. As steaming conditions, a treatment under 15 lb of pressure and 10 minutes of heating shows most effective. 2. The optimum pH of Asp, sojae enzyme for the digestion of soybean protein is 6.0, while that of Asp. niger enzyme is 4.4. In successievly-decomposing with Asp. sojae and Asp. niger, it shows the most effective on ratio of water-soluble-nitrogen to total nitrogen and amino-nitrogen to total nitrogen than any other separate treatments. 3. The suitable amount of the enzyme solution to that of the soybean substrate paste, in volume, is 1 : 2. 4. Digestion ratio of soybean protein indicates the gradual and steady effects of increasing time of digestion, but 8 hour-digestion regarding to putrefaction was suitable. 5. The most effective decolorization was successively passed on culumns of active carbon and anion exchanger (Dowex 2-x-8) at room temperature. In separate treatments, the effective order of decolorization was as follows; (Dowex 2-x-8)>Active carborn>Amberite IR-120 6. The powder type of the soy protein source obtained by concentration below $60^{\circ}C$ contains 12.51% of moisture, 66.31% of protein, 4.25% of fat, 12.75% of carbohydrate, 4.18% of ash.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.2
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• pp.146-154
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• 2014

In the result of effect on freezing damage reduction by the shade net colors and the shade rate to tea trees during wintering period, the high shade ratio decreased tea trees growth and increased freezing damage and 55% of shade ratio based on non treatment developed new leafs and green leaf productivity. By the shade net colors, colorless shade net (55% of shade type) treatment and green shade net treatment increased green leaf productivity and decreased damaged area compare to non treatment shade net and black shade net treatment. Colorless net shade treatment reduced over 50% of freezing damage and increased (10a) 68 kg for green leaf productivity compare to non treatment shade net. The colors of shade net treatments for reduction freezing damaged in order of Black < Green < Colorless but reduction of freezing damage was so high. In the relative microclimates, treatment shade nets were $0.7^{\circ}C$ lower, average relatively humidity 14.9% higher, soil temperature $0.6^{\circ}C$ lower and soil moisture 4.6% higher than non treatment shade net. And treatment shade nets decreased average wind speed 0.7 m/s and it showed us treatment net shades effected to excessive evapotranspiration and soil dry by wind and considered one of good solution for freezing damages.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.202-210
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• 2005

In this study, the fly ash was employed as a possible alternative to the bentonite for its high sorption capacity against cationic heavy metal. To consider the constituents of barrier possibly used, the specimens were mixed with different material contents (fly ash : weathered soil : bentonite), then sorption test was performed. Also the specimens were molded on the wet side of optimum moisture contents like mixing ratio of sorption test and their hydraulic conductivities were measured in flexible-wall permeameters. And to confirm the effect of dissolved cations, the hydraulic conductivity tests were repeated by converting the permeant liquids from water to $Cd^{2+}$ solution. Finally, the Cd-concentration at the effluent was analyzed for 500hrs to compare the effectiveness of each specimen in contaminant retardation. Test results showed that the more the ratio of fly ash increase, the more Kd value increase, and the hydraulic conductivity of weathered soil/bentonite (95:5) mixture was the lowest $(2.9*10^{-8}cm/sec)$, and specimens made of fly ash and fly ash/weathered soil mixtures showed similar hydraulic conductivity. Although the permeant liquid was changed from water to $Cd^{2+}$ solution, the hydraulic conductivity of all specimens except for weathered soil maintained similarly like before. Consequently, the initial breakthrough point of Cd in weathered soil specimen was observed at about 5hrs after the test started while that of fly ash specimens was not observed during the whole test period of 500hrs. The results implied that fly ash had a sufficient retardation capacity against contaminant transport possibly by its high sorption capacity although it showed little effect on the reduction of hydraulic conductivity. Based on the test results, it could be concluded that the fly ash can be possibly used as a suitable barrier material in containment system to attenuate the contaminant transport for its high retardation capacity and for the low cost.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.19-25
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• 2008

This study was carried out to investigate the bending strength properties of the unreinforced glulam beams and the GFRP laminated glulam beams according to the volume ratio of GFRP. The 7-layer glulam beams ($10cm(b){\times}14cm(h){\times}180cm(l)$) were manufactured, using Larch (Larix kaempferi Carr.) laminae ($2cm(h){\times}10cm(b){\times}360cm(l)$), which were dried to the moisture content of 8% and specific gravity of 0.54. GPRP of 0.1 and 0.3 cm was reinforced between the outmost layer of bottom and next layer. When the glulam beams were reinforced with GFRP at the volume ratio of 0.7% and 2.1%, respectively, the bending strength was increased by 12% and 28%, respectively, in the reinforced beams than in control glulam beams. Also, the GFRP reinforced layer of the glulam beams with GFRP laminations blocked the progression of rupture, and the unbroken part held about 90% of the bending strength. In the results of glue joints test, the block shear strength is higher than $7.1N/mm^2$, the standard of KS F3021, and in the result of delamination, the adhesive strength is good as the water soaking and boiling delamination was less than 5%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.177-181
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• 2011

This research was carried out to establish perfect-drainage time in order to stabilize rice yield and improve rice quality. Treatments of perfect-drainage were conducted 5 days interval during 25 days to 50 days after heading date in the field of Saemangeum Gyehwa, newly reclaimed land. Accumulated temperature after heading date in 2010 increased about $100^{\circ}C$ and precipitation amount decreased a little compared to normal year harvesting time. Average panicle number was 16.5 and spikelet per panicle was 88. Perfect drainage time treatment after 40~50 days was 3% higher in percent ripened grain and 0.6 g heavier in 1,000 grain weight than treatment after 25~35 days. There was no difference of rice yield between perfect drainage time treatment after 25 days and 30~35 days, but rice yield was 7~8% higher in treatment after 40~50 days than 25 days. Head rice ratio in treatment after 35 days was the highest and the sooner perfect drainage time, the lower protein content. Soil moisture negatively correlated with soil hardness and EC in this result. With this results, we proposed that the time of perfect drainage in newly reclaimed land to stable rice production is 40~50 days after heading date.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.146-150
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• 2009

Sliced ginger samples were dried using 30, 50, and 80% maltodextrin, respectively, as a dehydrating agent. The moisture content of the maltodextrin-treated ginger decreased with increasing concentrations of maltodextrin. The dehydrated ginger was compared with hot air-dried and freeze-dried ginger samples in terms of rehydration ratio, gingerol content, color, and sensory characteristics. The rehydration ratio of the maltodextrin-treated ginger was superior to those of the hot-air dried or freeze-dried ginger. In addition, the maltodextrin-treated ginger had the highest content of 6-gingerol among the samples. Color as well as sensory scores for odor, texture, appearance, and overall acceptance were greater for the maltodextrin-treated ginger compared to the hot-air dried or freeze-dried ginger. These results indicate that drying ginger with maltodextrin is very efficient because good rehydration capacity is retained and minimal cell destruction can be achieved.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.535-541
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• 1996

A seed pelleting technique was developed for easy handling of small tobacco seeds (variety, NC82) and for direct seeding in temperary planting bed or in field. The mixture of pelleting material, binder and seeds were moulded in cylindrical holes sized 2 mm diameter and 2 mm height in a plastic plate. Bentonite and cellulose powder were good materials to make pellets with CMC as binder, and bentonite formed the hardest pelleted seeds among the materials. The number of the pelleted seeds made with the same weight of the materials was different with materials used and the number of seeds contained in a pelleted seed could be controlled by mixture ratio of materials and seeds. The seedless pellets ranged 6.9 to 16.0% at the ratio of pelleting material and seed for 2~3 seeds in a pellet. The moisture absorption rate at 100% RH and $25^{\circ}C$ was greater in the order of clay < bentonite < cellulose. Germination rates of pelleted seeds with bentonite and cellulose were similar to that of usual seed, but it was significantly lower with clay pelleted seeds.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.491-496
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• 1998

The composition of isocyanates and polyols influence prepolymeric properties of adhesive and calking sealant based on polyurethanes (PU). One component moisture curing prepolymers, which reacted with surface humidity of substrate, were synthesized in several kinds of composition. Reactivity, structural change and properties of the prepolymers were studied as a preliminary step to manufacture PU based adhesive and sealant. To study the effects of mole ratio ([NCO]/[OH]), we used toluene diisocyanate (TDI), 4, 4'-diphenylmethane diisocyanate (MDI), and ether-polyols such as PTMG and PPG which have good resistance to hydrolysis and excellent low-temperature properties. The each prepolymers could be prepared in different molecular weight without any significant structural change. The mole ratio 1.78 of [NCO] to [OH] showed the fastest reactivity. It was confirmed that effect of polyols was larger than that of isocyanates on the prepolymer in reactivity. Several kinds of compounds were manufactured with each prepolymer, and tensile and properties were tested. And the optimum quantity of curing accelerator for the PU was 0.05~0.1%. In the tensile test, TDI based PU was superior to MDI based PU, and also PTMG based PU was superior PPG based PU.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.237-242
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• 1998

This study was carried out to process canned ark shell with highly quality by management of proper processing conditions for prevention of oxidation and discoloration by heating. Ark shell has hemoglobin as blood pigment in red blood shell which same as other cockles. Hemoglobin is easy to come oxidation and browning reaction, and it has large contents of carotenoid as meat pigment. Proximate compositions in ark shell were 76.9% of moisture, 18.1% of crude protein, 1.8% of crude lipid, 1.3% of carbohydrate and 1.6% of crude ash. And contents of carotenoid and hemoglobin were 0.67~1.02mg% and 0.98~1.64g/dl, respectively. When the living ark shell was soaked in 2% NaCl solutions, about 89% of mud was removed after 10 hours soaking, and over 91% was removed when the pH was adjusted to 7.5. Carotenoid pigment were prepared that extracted from ark shell by using acetone. And determined visible spectrum were two peak at 452nm and 687nm, and λmax were 452nm. During thermal treatment at 95$^{\circ}C$, 111$^{\circ}C$, 116$^{\circ}C$ and 121$^{\circ}C$ for 60 minutes, retention ratio of carotenoid were 71.8%, 66.8%, 64.4% and 36.5%, and after 120 minutes retention ratio were 56.6%, 30.6%, 30.3% and 17.2%, respectively. When heated at 95$^{\circ}C$, 111$^{\circ}C$, 116$^{\circ}C$ and 121$^{\circ}C$, formation of browning material were increased at high temperature and long time treatment.

• Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.7.1-7.8
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• 2020

Background: To minimize the use of antibiotics and to obtain a more sustainable fish culture and aquaculture industry, development of alternative natural source of immunostimulant to replace antibiotic in aquafeed is highly needed. Objective: Dietary inclusion effect of yacon (YC), ginger (GG), and blueberry (BB) on growth, body composition, and disease resistance of black rockfish against Vibrio anguillarum was compared to ethoxyquin (EQ). Methods: Four hundred eighty juvenile (an initial weight of 4.2 g) fish were randomly distributed into 12 of 50 L flowthrough tanks (forty fish per tank). Four experimental diets were prepared; the control (Con) diet with 0.01% EQ inclusion, and YC, GG, and BB diets at 1% each additive inclusion. Each additive was included into the experimental diets at the expense of wheat flour. Each diet was assigned to triplicate tanks of fish and hand-fed to satiation twice daily for 8 weeks. At the end of 8-week feeding trial, 20 fish from each tank fish were artificially infected by intraperitoneal injection with 0.1 mL of culture suspension of pathogenic V. anguillarum containing 3.3 × 10⁶ cfu/mL respectively. Fish were monitored for the following 8 days after V. anguillarum infection and dead fish were removed every 6 h for the first 4 days and 12 h for the rest of the study. Results: Weight gain, specific growth rate (SGR), and feed efficiency ratio (FER) of fish fed the YC diet was higher than those of fish fed all other diets. However, feed consumption, protein efficiency ratio, and protein retention was not affected by dietary additive. Moisture, crude protein, and crude lipid content of the whole body of fish were affected by dietary additive. Analysis of the Kaplan-Meier survival curves showed that survival of fish fed the YC, BB, and GG diets was higher than the Con diet. Conclusion: Oral administration of YC can improve not only weight gain, SGR, and FER of black rockfish, but lower mortality of rockfish at occurrence of V. anguillarum.