• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.381-385
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• 2009

A basic objective is the preparation and surface studies of supported molten salt catalysts because molten salts can stay as the liquid phase in the range of the ordinary reaction temperature. Many kinds of metal salt mixtures for the formation of molten salt phase are appliable but CuCl and KCl were selected in this study because Cu is considered catalytically reactive in many reactons. The loading of the molten salt was selected as 25 vol% of the total pore volume of ${\gamma}-alumina$ to provide reasonable exposed surface area. The surface structure of catalysts containing molten salts in the ${\gamma}-alumina$ was studied using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). CuCl and KCl were added into the ${\gamma}-alumina$ using concentrated hydrochloric acid solution by the impregnation technique. The surfaces of the prepared catalysts before and after heat treatments were compared and they suggested that the heat treatment of catalysts helped the formation of molten-salt although the surface compositions of CuCl and KCl were not uniform.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.794-801
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• 2015

This study investigated the quality characteristics and antioxidant effect of muffins that were prepared with the following lemongrass-powder concentrations: 0%, 1%, 3%, 6%, and 9%. The lemongrass-powder concentrations were added to the flour during the basic-formulation process, whereby the heights and volumes decreased significantly when the amount of lemongrass powder was increased. As a result of measuring the colors, the lightness and yellowness of the muffins decreased, whereas the redness increased with the increases of the lemongrass-powder concentrations. When the textures of the lemongrass muffins were measured, the chewiness and adhesiveness decreased with the increases of the lemongrass-powder concentrations. When the sensual qualities of the muffins were measured, the colors, flavors, tastes, textures, and overall quality of all of the samples show that the 3% lemongrass-powder concentration revealed the highest sensual-quality indexes. Further, the DPPH and ABTS radical-scavenging activities increased according to the concentration of lemongrass powder, whereby the former increased significantly when the amount of lemongrass powder was increased.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.192-199
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• 1991

To manufacture a good organic fertilizer through rapid composting process, cow dung was mixed with bulking materials such as rice straws, shredded bark, wood chips, and saw dust. The mixing ratio of the cow dung and bulking material was two to one on volume basis and moisture content was adjusted to 60 to 70 percent, C/N ratio 25 to 30 and aeration forced with suction during the aerated pile fermentation. Aerated pile was established outdoors and curing pile was in vinylhouse and the experiment was conducted for 3 years from '88 to '90. After pilling, temperature in aerated pile was reached to the maximum level at 7 to 9 days and the temperatures of cow dung + shredded bark, cow dung + wood chips, and cow dung + rice straws were higher than that of cow dung, and cow dung + saw dust. Total carbon, and C/N ratio in aerated pile fermentation period were increased in the middle stage and then they were decreased with the process of days, and nutrient contents in curing pile period had the same tendency as in the aerated pile.

• Membrane Journal
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• v.17 no.2
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• pp.146-160
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• 2007

A parametric study on pervaporation-facilitated esterification was performed by using a practical model based on non-perfect separation through membrane which is not perfectly permselective to water. Thus, membrane selectivity as well as membrane capability to remove water should be taken into account in establishing the simulation model to explain how the membrane separation influence the esterification reaction process. It was shown by simulation that in the reaction systems with non-perfect separation, the permeation of reactants which are acid or/and alcohol retards the reaction by inducing the backward reaction so that reaction conversion curve is located between a reaction system coupled with pervaporation process having a perfect permselectivity to water and a reaction system without pervaporation process. The volume change of reaction system occurs as a result of the permeation through the membrane. The reaction volume change which can be characterized by the reaction ratio of $r_{\Psi}\;to\;r_{{\Psi}=1}$ affects reaction kinetics by concentrating reactants and products, respectively, with different extent with time; reactant-concentrating effect is dominant during the initial stage of reaction, resulting in facilitating the reaction, and then product-concentrating effect is exerted more on reaction, causing to slow down the reaction. When pervaporative dehydration is applied to the reaction system plays an important role in the reaction as well. The effect of timing to impose pervaporation on reaction system affected the reaction kinetics in terms of reaction rate and reaction conversion. A relationship was derived to explain membrane unit capacity and reaction parameters that will be used as a design tool to determine membrane unit capacity at a given reaction conditions or reaction parameters at a membrane unit capacity.

• Membrane Journal
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• v.17 no.2
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• pp.124-133
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• 2007

In this study, we treated lake water by 2 kinds of multichannel ceramic micro filtration membranes. We could investigate effects of $N_2-back-flushing$ time (BT) and transmembrane pressure (TMP), and find optimal operating conditions. The BT were changed in $10{\sim}60$ sec, TMP in $0.6{\sim}2.0$ bar at fixed filtration time (FT) 8 min, flow rate 2.0 L/min and back-flushing pressure 2.0 bar. Also, the optimal conditions were discussed in the viewpoints of resistance of membrane fouling $(R_f)$, dimensionless permeate flux $(J/J_o)$, permeate flux (J) and total permeate volume $(V_T)$. As result, optimal back-flushing conditions for HC04 ($0.4{\mu}m$ pore size) and HC10 membrane $(1.0{\mu}m)$ were BT=10 sec and BT=20 sec, respectively. Then, higher TMP should increase the driving force, and could produce more VT. Average rejection rates of pollutants were higher than 95.4% for turbidity, $12.7{\sim}20.1%\;for\;COD_{Mn},\;0.0{\sim}6.4%\;for\;NH_3-N,\;1.9{\sim}4.6%$ for T-N and $34.9{\sim}88.4%$ for T-P.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.289-295
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• 1999

Halotolerant microalga Dunaliella bardawil was reported to massively accumulate the ${\beta}$-carotene, which protects cells from excess light intensity. Maximum specific growth rate of 0.168/hr was achieved when cells were cultivated at 1 N NaCl, pH 8.0, light intensity 80 ${\mu}E/m^{2}/s$, agitation 70rpm. For the effectiv accumulation of ${\beta}$-carotene, ozone ro hydrogen peroxide was added to media which was irradiated with white fuorescent lamps with moderate light intensity of 250 ${\mu}E/m^{2}/s$. As a result, maximum volumetric content of ${\beta}$-carotene was 324 ${\mu}$g/㎖. The ${\beta}$-carotene extraction efficiency of vegetable oils was in the order of olive oil, sesame oil, rice brain oil, corn oil, and soy bean oil. Sonication and warming was effective in ${\mu}$-carotene extraction and finally 96.9% of ${\beta}$ could be extracted using olive oil.

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.29-34
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• 2002

An experiment was conducted to evaluate shattered industrial polyurethane (PUR) and cellular glass foam (CGF) as growth medium components. Pot chrysanthemum 'Pink Pixie Time 'was cuttured in media containing various volume ratios of PUR, CGF, peatmoss, coir, and perlite. Before plant culture, pH and EC of media were determined. Container capacity (%) was low in perlite and CGF-containing media, but it increased when incorporation ratio of peatmoss or coir was increased. pH was stable between 5.0 and 6.3, but was high in coir-contaning media as compared to other media tested. EC was very high in coir-containing media. Hight at 34 days after planting was the greatest in media containing CGF, and number. of leaves was similar among treatments. Growth in PUR-containinly media was poorer than that in the other media, with some leaf edge burning. Trends in growth measured at 97 days after planting was similar to that measured at 34 days after planting.

• Journal of the Korean Vacuum Society
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• v.16 no.2
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• pp.79-90
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• 2007

Prototype of $800{\ell}$ vacuum web coater (Vic Mama) consisting of ion source with low energy less than 250 eV for high speed surface modification and 4 magnetron sputter cathodes was designed and constructed. Its performance was evaluated through fabricating the adhesiveless flexible copper clad laminate (FCCL). Pumping speed was monitored in both upper noncoating zone pumped down by 2 turbo pumps with 2000 l/sec pumping speed and lower surface modification and sputter zone vacuumed by turbo pumps with 450 1/sec and 1300 1/sec pumping speed respectively. Ion current density, plasma density, and uniformity of ion beam current were measured using Faraday cup and the distribution of magnetic field and erosion efficiency of sputter target were also investigated. With the irradiation of ion beams on polyimide (Kapton-E, $38{\mu}m$) at different fluences, the change of wetting angle of the deionized water to polyimide surface and those of surface chemical bonding were analyzed by wetting anglometer and x-ray photoelectron spectroscopy. After investigating the deposition rate of Ni-Cr tie layer and Cu layer was investigated with the variations of roll speed and input power to sputter cathode. FCCL fabricated by sputter and electrodeposition method and characterized in terms of the peel strength, thermal and chemical stability.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.124-124
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• 2001

난소화성전분(resistant starch, RS)는 건강한 사람의 소장에서 흡수되지 않는 전분과 분해된 전분의 산물을 총칭하는데. 대장에서 발효와 미생물성장, 식후 혈당, 변부피, 장통과시간, 식품의 열량가 등에 영향을 미치므로 생리적인 이점을 갖는다. 본 연구에서는 고지방식이와 콜레스테롤을 섭취란 흰쥐에서 제조과정이 다른 RS의 섭취가 저 열량원으로서 체중감소나 혈액내 지방성분을 낮추는 효과가 있는지를 알아보는 것을 목적으로 하였다. 연구방법으로 실험동물은 생후 4주된 Sprague-Dawl ey계 수컷 흰쥐로, 지방을 식이 무게의 20%, 콜레스테롤이 식이 무게의 1%로 첨가 된 고지방식이로 6주를 사육시켜 비만과 고콜레스테롤증을 유발시켰다. 고콜레스테롤이 유발된 실험동물은 섭취하는 전분의 형태가 다른 실험식이로 4주간을 더 사육하였고 사육기간이 끝난 실험동물들은 희생하여 생화학적인 실험- 혈액과 간의 총지방양, 중성지방양, 콜레스테롤양을 측정하였고, 면역능력으로 비장세포 증식, 혈장내 IgG, $C_3$양을 측정하였고. 혈장내 leptin 양을 측정하였다. 실험결과는 체중과 체내 저장지방무게가 난소화성전분 혼합군(RSNE)에서 유의적으로 감소하였다. 혈장내 지방성분을 보면, 총 지방의 경우 고지방대조군(HC)이 저지방 대조군(LC)에 비래 유의적으로 높았으며, RS를 섭취하면 유의적으로 낮아지는 경향을 보여 저지방을 섭취한 LC군에 비해서 낮은 수치를 나타내고 있다. 혈장 중성지방은 저지방 즉 고 탄수화물식이를 섭취하는 LC군이 유의적으로 높았으며 고지방을 섭취하는 경우는 실험군에 차이가 없었다. 혈장 총 콜레스테롤은 LC군에 비해 고지방과 콜레스테롤을 섭취하는 HC군이 유의적으로 높았으며. RSNE군에서는 유의적인 감소를 보였다. HDL-콜레스테롤에서는 실험군간에 차이가 없었다. 간내 총지방과 콜레스테롤량, 중성지방량은 LC군이 다른 군에 비해 유의적으로 적었으며 고지방섭취군들은 섭취하는 전분의 종류에 따른 차이가 나타나지 않았다. 면역능력을담당하는 체내 기관인 비장세포의 중식능력은 실험군간에 유의적인 차이가 없으나 혈장의 Ig G 양은 RSNE군이 유의적으로 높고, $C_3$ 양은 난소화성 전분 추출군(RSEX)에서 유의적으로 높게 나타났다. 혈장에서의 leptin 농도는 고지방 대조군인 HC군이 유의적으로 높았으며, RSNE군이 LC군과 같이 유의적으로 낮았다. 결론으로 난소화성 전분(RS)를 식이무게의 10%로 첨가하는 수준에서 순수한 RS보다는 RS제조과정 중 순수한 RS를 분리하기 전 단계인 RS를 포함한 전분이 체중감소, 체내 저장지방감소, 혈액 내 콜레스테롤을 저하시키는 효과를 보였다. 그러므로 RS의 섭취는 섭취형태에 따라 저 열량원으로, 혈액 내 지방성분을 낮추는 효과를 가진 기능성 식품소재로 사용될 수 있을 것이다.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.1
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• pp.29-38
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• 2005

The fluid animation procedure consists of physical simulation and visual rendering. In the physical simulation of fluids, the most frequently used practices are the numerical simulation of fluid particles using particle dynamics equations and the continuum analysis of flow via Wavier-Stokes equation. Particle dynamics method is fast in calculation, but the resulting fluid motion is conditionally unrealistic The method using Wavier-Stokes equation, on the contrary, yields lifelike fluid motion when properly conditioned, yet the complexity of calculation restrains this method from being used in real-time applications. Global illumination is generally successful in producing premium-Duality rendered images, but is also excessively slow for real-time applications. In this paper, we propose a rapid fluid animation method incorporating enhanced particle dynamics simulation method and pre-integrated volume rendering technique. The particle dynamics simulation of fluid flow was conducted in real-time using Lennard-Jones model, and the computation efficiency was enhanced such that a small number of particles can represent a significant volume. For real-time rendering, pre-integrated volume rendering method was used so that fewer slices than ever can construct seamless inter-laminar shades. The proposed method could successfully simulate and render the fluid motion in real time at an acceptable speed and visual quality.