• The Korean Journal of Community Living Science
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• v.15 no.4
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• pp.61-66
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• 2004

To develop natural food preservatives with Maesil (prunus mume), investigation of antimicrobial activities against food-related bacteria and yeast was conducted. Maesil (prunu mume) extract exhibited growth-inhibiting activities for most of the microorganisms tested. Minimum inhibitory concentrations (MIC) of maesil extract for Staphylococcus aureus and Bacillus subtilis were as low as 0.1mg/ml. The antimicrobial activity of the maesil (prunu mume) extract was reduced by heating or alkali treatment. Moreover, growth of Staphylococcus aureus was completely inhibited within 24 hours by the addition of at least 100 ppm of maesil extract. These findings suggest that maesil extract may play a role in the development of natural food preservatives.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.97-105
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• 1998

Antioxidation mechanism of Al metal powders on $Al_2O_3-C$ refractory was investigated in temperature range from 800 to $1400^{\circ}C$. The addition of 5 wt% Al metal powders suppressed the oxidation of carbon in $Al_2O_3$-C sample. The carbons were distributed uniformly on the surface and the interface of the $Al_2O_3$-C-Al. Reaction products of $Al_4C_3$ and AIN were found with a composition of Al-C at temperatures between 800 and $1200^{\circ}C$ and transformed to $Al_2O_3$ above $1400^{\circ}C$. Cavity structures related to the to the formation of $Al_4C_3$ were observed for the AI-C after heating at $1000^{\circ}C$ ofr 1 hour. Thermodynamic mechanism was considered to discuss the formation $Al_4C_3$, AlN and their transformation to $Al_2O_3$, which leads to the effect of oxidation resistance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.244-248
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• 2004

Ethanol extract of Agrimoniae Herba showed strong antimicarobial activity againt Listeria monocytogenes, Staphlococcus aureus, Salmonella typhimurium, Escherichia coli and Aeromonas hydrophila subsp. hydrophila The growth of tested organisms was significantly inhibited above 4 log in tryptic soy broth with about 0.12%(w/v) of Agrimoniae Herba after incubation for 12 hrs at 37$^{\circ}C$. Antimicrobial activity of Agrimoniae Herba was decreased by heat treatment at above 8$0^{\circ}C$. But Agrimoniae Herba showed strong inhibitory effect after heat treatment at 121$^{\circ}C$ for 15 min. The growth of L. monocytogenes was inhibited by addition of 0.6% Agrimoniae Herba in food system (ham homogenate).

• Journal of computational fluids engineering
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• v.21 no.2
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• pp.90-98
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• 2016

A numerical study is conducted on thermal performance of a large-area hot plate specially designed as a heating and cooling tool for thermal nanoimprint lithography process. The hot plate has a dimension of $240mm{\times}240mm{\times}20mm$, in which a series of cartridge heaters and cooling holes are installed. The material is stainless steel selected for enduring the high molding pressure. A numerical model based on the ANSYS Fluent is employed to predict the thermal behavior of the hot plate both in heating and cooling phases. The PID thermal control of the device is modeled by adding user defined functions. The results of numerical computation demonstrate that the use of cartridge heaters provides sufficient heat-up performance and the active liquid cooling in the cooling holes provides the required cool-down performance. However, a crucial technical issue is raised that the proposed design poses a large temperature non-uniformity in the steady heating phase and in the transient cooling phase. As a remedy, a new hot plate in which heat pipes are installed in the cooling holes is considered. The numerical results show that the installation of heat pipes could enhance the temperature uniformity both in the heating and cooling phases.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.398-405
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• 1986

The food quality of lupin seed, i.e. soaking, cooking, sprout growing and mold growing for fermentation, was investigated by using the seed of Lupinus angustifolius harvested in Western Australia. A method to produce lupin seed protein concentrate (LPC) was developed, and the wage of LPC in Korean food system was investigated. The water soaking rate of lupin seed was faster than that of soybean, but the cooking rate of lupin seed was much slower compared to soybean. The thermal softening time, $D_{100}$, was 345 min for lupin seed and 84 min for soybean. A two-phase solvent extraction system consisting of haxane-alcohol-water could effectively remove the residual bitter taste, lipid and yellow pigments of lupin seed flour, and the resulting LPC contained over 50% protein and had bland flavor and milky white color. Treatment of LPC with carbohydrate decomposing enzymes resulted in a product of more soluble and higher concentration of protein. Methods to produce lupin seed vegetable milk and lactic beverages from LPC products were discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.4
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• pp.174-178
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• 2008

Nano-crystalline slaked lime was synthesized using design of experiment. In order to synthesize slaked lime, calcium chloride $(CaCl_2)$ and urea were used as starting materials. Calcium chloride solution and urea solution were mixed and heated in vessel that calcium carbonate was precipitated during heating. Precipitates were filtered, washed several times using D.I.water and ethanol and finally dried in oven. Slaked lime $(Ca(OH)_2)$ has been fabricated by the hydration of calcined $CaCO_3$. Design of experiment (Taguchi method) was used to optimize parameter, to minimize noise factors of experiment and to statistically analyze the results. Slaked lime having about 50 nm in optimized crystallite size could be obtained by calcination of $CaCO_3$ at $1000^{\circ}C$ for 0.5 h and hydration with D.I water containing ethanol and oxalic acid.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.170-170
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• 1994

항암제 KR 53170 및 관련 화합물의 항암 효과에 관한 연구의 일환으로 Phellinus linteus 균사배양물로부터 분리한 항암성 단백다당체 (분자량 8000 이상의 고분자 분획) PL-KP률 장내세균의 효소활성을 이용하여 부분분절(partial fragmentation)시킴으로써 항암력 증강 가능성을 검토하였다. 1. 장내세균을 이용한 PL-Kp의 처리 :PL-Kp 5.62g을 기본배지 281m1에 용해 시킨후 그 중 100m1에는 Py-92 균주(endoglucanase 생성균주)를, 다른 100m1에는 초식동물로부터 분리한 활성 균총을 접종한후 배양물 100m1 당 BH1 broth 10n1를 첨가하고 24시간 배양하였다. 배양물을 원심분리하여 그 상등액을 열탕에서 15분간 가열하고 투석, 동결건조하여 건조분말로 획득하였다. 이증 Py-92 균주로 처리한 시료를 Kp-F1, 균총으로 처리한 시료를 Kp-F2, 균을 접종하지 않고 처리한 시료를 Kp-FC라 한다. 2. 분절 (Fragmentation) 확인 : 증류수에 용해시킨 시료의 Sephadex G-25 컬럼을 이용한 gel filtration 유형(컬럼 통과 속도 및 착색대 유형)등을 관찰하여 Kp-F1 및 Kp-F2가 성공적으로 분절되었음을 확인하였다. 3. 분절 Kp의 항암력 실험 : ICR 마우스내 피하에 이식한 sarcoma 180고형암에 대한 항암력을 비교실험하여 부분분절에 의해 항암력이 증가 여부를 확인하였다. 그 결과 PL-Kp가100mg/kg/day ip의 용량에서 49.5%의 종양저지율을 발휘하였으나 균총을 이용하여 부분분절시킨 시료(Kp-F2)는 그 1/5용량에서도 87%의 종양저지율을 발휘하여 항암력이 현저히 증가 되었음을 확인하였다. 한편 Py-92 균주를 이용하여 분절시킨 Kp-F1도 100mg/kg용량에서 76%의 종양저지율을 나타내었다. 이로써 부분분절 조작을 통하여 항암성 단백다당류인 PL-Kp 의 항암력을 현저히 증가시킬 수 있음이 입증되었다.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.1-8
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• 2007

The purpose of this study is to conduct a survey of the flame stability range and the emission characteristics for the optimum design of turbulent premixed flat burner. For that, the flame stability range was selected by the direct photography of the flame. And the mean temperature and CO, HC, $CO_{2}\;and\;O_{2}$ concentration distributions by changing the excess air ratio were measured. As results of this study, the flame stability range turned out to be getting narrower as fuel flow was increased. The blue flame mode was more excellent than any other flame modes in the emission characteristics by excess air ratio change. And the emission characteristics by fuel flow change were best at fuel flow 1l/min. Also, we found combustion noise during experiment of flame stability range. It had nothing do with excess air ratio range.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.12
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• pp.953-963
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• 2015

There is an increasing need to understand the thermal-hydraulic phenomena, including the critical heat flux (CHF), in narrow rectangular channels and consider these in system design. The CHF mechanism under a saturated flow boiling condition involves the depletion of the liquid film of an annular flow. To predict this type of CHF, the previous representative liquid film dryout models (LFD models) were studied, and their shortcomings were reviewed, including the assumption that void fraction or quality is constant at the boundary condition for the onset of annular flow (OAF). A new LFD model was proposed based on the recent constitutive correlations for the droplet deposition rate and entrainment rate. In addition, this LFD model was applied to predict the CHF in vertical narrow rectangular channels that were uniformly heated. The predicted CHF showed good agreement with 284 pieces of experimental data, with a mean absolute error of 18. 1 % and root mean square error of 22.9 %.

• Journal of Energy Engineering
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• v.7 no.2
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• pp.209-215
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• 1998

This paper investigated the vertical throughflow effects on natural convection due to heating from below in horizontal porous layer. The motion of the fluid in the porous layer is governed by Brinkman-Darcy equation. And compared Critical Rayleigh number in case of throughflow with no throughflow. Investigated Nusslet number, isothermalline and flow with the variation of the strength of throughflow in a constant Rayleigh number. In the numerical analysis, flow is assumed to be two-dimensional and unsteady. The numerical scheme used is a finite-difference method. In the experimental study, Temperature distribution was measured by use of Liquid Crystal film. As a results, indicated that throughflow influences largely on the temperature field and as the strength of throughflow increased, unstability of natural convection decreased. Also it could predict the strength of natural convection with the measured Nusselt number.