• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.680-686
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• 1997

Ultrafiltration and reverse osmosis were applied to produce soy-oligosaccharides from yeast fermented bean cooking water (BCW). The recovered total sugar by the ultrafiltration of bean cooking water on a cutoff molecular weight membrane of 20,000 and 5,000 was over 80%. The protein was removed up to 38% from the non-fermented BCW, 31% by S. cerevisiae KCTC 7039 and 21% by H. anomala KFRI 626. The recovery of oligosaccharides was above 70%, although fermented or non fermented bean cooking water was different on the recovery of oligosaccharides. The ultrafiltrated BCW was concentrated by reverse osmosis with respect to the volume concentration ratio (VCR). Total solid, total sugar, ash and protein contents increased up to VCR of 3.5 and then levelled off, showing that the optimum VCR was 3.5.

• Applied Biological Chemistry
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• v.11
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• pp.63-66
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• 1969

The purification methods of bacterial protease have been published by many workers, especially by the using of ion exchange resins. But in the practical application to obtain a comparatively purified enzyme, the known methods do not give always a satisfiable results. Here we developed an industrially applicable method for purification of bacterial protease with the using of tannin. By the adaptation of the optimal conditions of this method on the purification, a 150000 unit/g. (Fuld Gross unit) of protease sample could obtained.

• Resources Recycling
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• v.3 no.1
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• pp.32-37
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• 1994

Mercury in spent button type batteries can be separated and recovered with vacuum distillation method. It was found that mercury in the battery began to distill at $150^{\circ}C$ and organic substanced like a packing material was decomposed at$ 300^{\circ}C$. More than 99.9% of mercury contained in the battery was distiled and separated at about $250^{\circ}C$ and 20 torr with 8 hours' reaction time. The dissolution tests of the residue after distillation showed that mercury concentration in the solution were lower than 5 ppb and this values satisfied the environ-mental condition. Also as the furnace heating rate was above $15^{\circ}C$/min, it was found that the spent battery was destroyed because of increased pressure in the battery inside.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.101-107
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• 2002

This study was carried out to improve the performance of heat recovery device attached to exhaust gas flue connected to combustion chamber of greenhouse heating system. Three different units were prepared far the comparison of heat recovery performance; A-type is exactly the same with the typical one fabricated for previous study of analyzing heat recovery performance in greenhouse heating system, other two types (B-type and C-type) modified from the control unit are different in the aspects of airflow direction (U-turn airflow) and pipe arrangement. The results are summarized as follows ; 1. In the case of Type-A, when considering the initial cost and current electricity fee required for system operation, it was expected that one or two years at most would be enough to return the whole cost invested. 2. Type-B and Type-C, basically different with Type-A in the aspect of airflow pattern, are not sensitive to the change of blower capacity with higher than 25m$^3$.min$^{-1}$ . Therefore, heat recovery performance was not improved so significantly with the increment of blower capacity. This was assumed to be that air flow resistance in high air capacity reduced the heat exchange rate as well. Never the less, compared with control unit, resultant heat recovery rate of Type-B and Type-C was improved by about 5％ and 13％, respectively 3. Desirable blower capacity of these heat recovery units experimented were expected to be about 25m$^3$.min$^{-1}$ , and at the proper blower capacity, U-turn airflow units showed better heat recovery performance than control unit. But, without regard to the type of heat recovery unit, it was recommended that comprehensive consideration of system's physical factors such as pipe arrangement density, unit pipe length and pipe thickness, etc., was required for the optimization of heat recovery system in the aspects of not only energy conservation but economic system design.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.542-548
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• 1989

For the selective separation of proteins, the solubilization and desolubilization of proteins in sodium-di-2-ethylhexyl sulfosuccinate (AOT)-isooctane reverse micellar system were investigated. Protein solubilization increased with increasing the concentration of AOT to 200 mM and then decreased above that concentration. Protein was solubilized into reverse micelles in the pH range below the isoelectric Point of each protein, pH 4-10 for lysozyme and pH 5-6 for trypsin and ${\alpha}-chymotrypsin$, Lysozyme, trypsin and ${\alpha}-chymotrypsin$ were efficiently extracted in the precence of KCl and NaCl while larger molecular weight proteins such as pepsin and BSA had high solubilization with $CaCl_2$. At higher ionic strength all proteins exhibited murk less tendency to solubilize and the increase of ionic strength resulted in the decrease of micelle size. Lysozyme was successfully back transfered at pH 12.2 and 1.0M KCl; trypsin at pH 12.6 and 0.5M KCl; and ${\alpha}-chymotrypsin$ at pH 6.7 and 0.5M KCl. In a test group separation experiments, complete separation of lysozyme from BSA could be obtained.

• Parasites, Hosts and Diseases
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• v.26 no.1
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• pp.9-14
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• 1988

In an attempt to determine the susceptibility of inbred golden hamsters(Mesocricetus auratus) to the experimental infection with Clonorchis sinensis, twenty-five hamsters were divided into 5 groups and administered orally 5, 10, 20, 30 or 50 metacercariae each. The hamsters were killed on the 45th day after infection. The adult flukes were recovered from all hamsters. The overall recovery rate for the fluke was 57.9% with the range of 48.4% to 92.0%. As the number of the metacercariae given increased, a porportionate decrease in the recovery rate was found, the prepatent period of the fluke in the hamster varied from 15 to 17 days, with the average of 16 days. No significant differences in the development of the flukes were observed. Egg production expressed by EPG, increased step by step as the time elapsed. However, a tendency of decreasing egg laying capacity was observed with the increase of worm burden. It is suggested that the hamster is a suitable final host of C. sinensis.

• Resources Recycling
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• v.26 no.3
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• pp.61-68
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• 2017

Cyclone electrowinning method was used to recover tin to metal in hydrochloric acid solution. The effects of flow rate, current density, tin concentration, and hydrochloric acid concentration on the electrowinning of tin were investigated. As the flow rate increased and the concentration of tin and hydrochloric acid decreased, the tin recovery and current efficiency increased. As the current density increased, the recovery rate increased but the current efficiency decreased. Tin can be effectively recovered at flow rates of 18 L/min., $3A/dm^2$, 2.5 g/L Sn, and 5 wt.% HCl.

• Resources Recycling
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• v.28 no.1
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• pp.23-31
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• 2019

Cementation is one of economical and efficient recycling method precipitating the metal ion in solution by adding another active metal. In this study for optimizing cadmium recovery efficiency, it was performed as a function of the effect of pH, temperature, particle size, and input amount of zinc in 0.1 M $CdSO_4$ solution and Ni-Cd battery leaching solutions, respectively. The particle size of zinc and temperature were key factors for Cd cementation and it was confirmed that the input amount of 2.6 of Zn/Cd ratio using granular-type zinc was optimal condition for selective Cd recovery efficiency at $25^{\circ}C$.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.232-238
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• 1996

This study was conducted to find out the optimum condition for $NH_4-N$ removal from wastewater by a zeolite column. The removal efficiency of $NH_4-N$ by a glass column packed with decreased with the increase in initial concentration, percolation velocity and fraction number. The result of multiple stepwise regressions, $NH_4-N$ removal efficiency by the zeolite column showed a high correlationship with various parameters such as percolation velocity, initial concentration, adsorption amount and fraction number. Theoretical formula by parameter coefficients of multiple stepwise regression was found to be $NH_4-N$ removal $efficiency=0.620{\times}amount$ of zeolite $-0.456{\times}percolation$ velocity $-0.212{\times}initial$ concentration $-3.038{\times}fraction$ number+100.1 In the case of the $NH_4-N$ removal efficiency in cattle farming wastewater, the experimental data were nearly coincident with the theoretical formula.

• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.107-113
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• 1981

Free sugars were isolated from ginseng root and its products and analyzed by using high performance liquid chromatogrphy. To isolate free sugars from aqueous sample solution fat-soluble components, crude saponin and protein were removed from the solution by extracting with benzene, water-saturated butanol and 80% ethanol, respectively. Free sugars found from both ginseng root and its products were fructose, glucose, sucrose and maltose, and the only sugar detected from red ginseng root and its products was rhamnose. Major sugar detected from fresh ginseng and white ginseng roots was sucrose, while sucrose and maltose were major sugars of red ginseng root.