• Food Science and Biotechnology
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• v.14 no.4
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• pp.543-546
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• 2005

Optimized conditions for protoplast preparation and regeneration from young hyphae of Monascus ruber were established. Heat shock treatment of spores gave rapid and synchronized germination. Spores collected from cultures grown for 7-8 days at $30^{\circ}C$ were germinated until over 70% germ tubes reached to 3-5 spore length. Enzymatic digestion of young hyphae was optimal with 50 mg/mL Glucanex in 0.1 M sodium citrate buffer containing 0.8 M mannitol as an osmotic stabilizer. Regeneration rate was around 10% when 0.8 M sorbitol was used as an osmotic stabilizer in regeneration medium. These conditions will be applied in genetic study of M. ruber that produces citrinin at high level and thus is good model strain for molecular genetic dissection of citrinin biosynthesis.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.454-460
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• 2012

The nano-sized zirconia powders were synthesized in an impregnation method using pulp and $ZrOCl_2{\cdot}8H_2O$ as an initial material. The synthesized powders were characterized by XRD and FE-SEM. The particle size of the powder was controlled by preparation conditions, such as drying temperature and time. As a result of the various drying and calcination conditions, 30~50 nm sized homogeneous zirconia particles were obtained at $800^{\circ}C$ for 1 h. Crystallization and the rapid growth of particles were accelerated with increasing calcination temperature and time. Tetragonal phase generated below $800^{\circ}C$ were transferred to monoclinic phase with increasing calcination temperature and time. Moreover, above $800^{\circ}C$, heat treatment time had very large influence on the particle growth, and the change of drying condition also had large influence on the growth of a crystal.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.2
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• pp.155-161
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• 1998

Response surface methodology (RSM) was used for optimizing preparation conditions and monitoring the quality of buckwheat mook prepared using buckwheat starch. The textures(hardness, adhesiveness, cohesiveness and gumminess) of buckwheat mook were decreased in inverse proportion to the increase of water content. the L and b values of Hunter color parameters in buckwheat mook were increased in proportion to the increase of water content. However, The a value of Hunter color parameters of buckwheat mook were decreased in inverse proportion to the increase of water content. Organoleptic properties(color, form, taste and mouth-feel) of buckwheat mook showed a maximum score in 700ml(water content), 14min(gelatinization time)

• The Korean Journal of Food And Nutrition
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• v.8 no.4
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• pp.335-343
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• 1995

In order to enhance the utility of alaska-pollack, the optimum conditions for the preparation of pronase hydrolysate. The optimum temperature and pH for the hydrolysis of alaska-pollack by pronase were 4$0^{\circ}C$ and pH 7.0. The reaction time and enzyme concentration were 4 hr and 1,000 units per g of substrate. Under the above optimum conditions alaska-pollack was hydrolysed by pronase yielding a hydrolytic degree of about 89eye. The bitterness and hyrophobicity of pronase hydrolysate were decreased with increasing reaction time. Hydrophobic amino acids(Tyr, Met, Ala, flu, Leu, and Phe) were increased for 2 hr, but fur thor hydrolysis was showed decrease of hydrophobic amino acids content. Palatable amino acids (Asp, Glu, Pro, Ser, Thr and Gly) were increased with hydrolysis time.

• Journal of Environmental Science International
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• v.13 no.3
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• pp.319-325
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• 2004

An experimental study on the preparation of monolithic porous polymers by environmentally friend process in supercritical carbon dioxide has been carried out. Polymerization mixture composed of a cross-linking monomer, initiator and functional co-polymer was charged in the reactor with sapphire window. After the system was purged with a flow of $CO_2$ for 15 min, the reactor was pressurized with liquid $CO_2$ up to 100 bars. The reactor was isolated from and placed back to the system via quick connector for shaking until the mixture had become fully homogeneous. The reactor was then heated and pressurized to the required reaction conditions and left overnight. After cooling and $CO_2$ evacuation, the polymer was removed from the reactor as dry, white, continuous monoliths. The effect of experimental conditions on the physical properties of porous polymer was systematically examined, and it was found that monomer content had a major effect on the physical properties of the polymers.

• Journal of the Korean Society of Food Culture
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• v.26 no.5
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• pp.468-477
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• 2011

Optimum preparation conditions for chicken head soup base were determined in terms of the effects of amount of chicken head and cooking time using response surface methodology based on sensory properties. Sensory properties that were evaluated were yellowness, turbidity, bloody, chicken-brothy, organ meat-like, and fat-like flavor. All values of sensory characteristics increased remarkably with an increase in the amount of chicken head and cooking time. The optimum amount of chicken head and cooking time were determined to be 1800 g and 150 minutes, respectively. Chicken head soup base had less fat, free amino acids, nucleotides, and its derivatives, but had significantly more cholesterol, sodium, and iron than whole chicken soup base. In flavor compound analysis, the amount of hexanal of the chicken head soup base, which is related to fat rancidity flavor, was 11-fold higher than that of the whole chicken soup base.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1096-1098
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• 1999

The performance of as plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the optimum preparation conditions of MgO Protecting layer by RF unbalanced magnetron sputtering(UBMS) in surface discharge type AC PDP. The samples prepared with the do bias voltage of -10V showed lower discharge voltage, lower erosion rate as a consequence of ion bombardment, higher optic transparency and higher crack resistance in annealing process than those samples prepared by conventional magnetron sputtering or E-beam eraporation.

• YAKHAK HOEJI
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• v.15 no.1
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• pp.24-31
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• 1971

Optimum reaction conditions for the preparation of extra-light magnesium carbonate from bittern by the reaction with sodium carbonate solution was found to be as follows: reaction temperature 33.deg. molar ratio(Mg$^{+2}/CO$^{2-}_{3}$)0.8, reaction time 14 minutes, drying temperature 99.deg. and bittern concentration 17%. While Korean pharmacopeia regulates the bulkiness above 12 mililiters per gm., our experimental result shows above 45 mililiters. Electron microscopic shapes were compared with products prepared under various reaction conditions, and it was found that there exists lighter the powder the more pillar crystalline, the heavier the powder the more amorphous and the intermediate was mixture of them.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.432-435
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• 1997

In AC PDP, electrodes are covered with dielectric layer and the discharge is formed on the surface of the dielectric layer. MgO protection layer on the dielectric layer in PDP prevents a dielectric layer from sputtering and lowers the firing voltage due to a large secondary electron emission yield( ${\gamma}$ ). Until now, the MgO protection layer is mainly prepared by E-beam evaporation. However, there are some problems that is easy pollution and change of its characteristics with time and delamination. Therefore, in this study, MgO protection layer is prepared on dielectric layer by reactive R.F. magnetron sputtering with MgO target. Discharge characteristics and secondary electron emission coefficients of PDP are studied as a parameter of preparation conditions. Discharge voltage characteristics of the prepared MgO layer can be stable and improved by the annealing process in vacuum chamber.

• Journal of the Korean Society of Industry Convergence
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• v.12 no.4
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• pp.193-202
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• 2009

In the preparation of anion charged asymmetric ultrafiltration membranes by the conventional phase inversion method, several variables could be adjusted to control membrane permeations. The anion charged materials and its original polymer have good solubility in N-methyl-2-pyrrolidone. The membranes having a hydrophilic property were less fouled the membrane prepared from the original polymer. The preparation conditions, operation conditions, and hydrophilicity of polymer have played an important role in determining the permeation properties of membranes.