• 한국식품조리과학회지
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• 제9권1호
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• pp.43-51
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• 1993

Buckwheat protein isolate was tested for the effects of pH, addition of sodium chloride and heat treatment on solubility, emulsion capacities, emulsion stability, surface hydrophobicity, foam capacities and foam stability. The solubility of buckwheat protein isolate was affected by pH and showed the lowest value at pH 4.5, the isoelectric point of buckwheat protein isolate. The solubility significantly as the pH value reached closer to either ends of the pH, i.e., pH 1.0 and 11.0. The effects of NaCl concentration on solubility were as follows; at pH 2.0, the solubility significantly decreased when NaCl was added; at pH 4.5, it increased above 0.6 M; at pH 7.0 it increased; and at pH 9.0 it decreased. The solubility increased above $80^{\circ}C$, at all pH ranges. The emulsion capacity was the lowest at pH 4.5. It significantly increased as the pH approached higher acidic or alkalic regions. At pH 2.0, when NaCl was added, the emulsion capacity decreased, but it increased at pH 4.5 and showed the maximum value at pH 7.0 and 9.0 with 0.6 M and 0.8 M NaCl concentrations. Upon heating, the emulsion capacity decreased at acidic pH's but was maximised at pH 7.0 and 9.0 on $60^{\circ}C$ heat treatment. The emulsion stability was the lowest at pH 4.5 but increased with heat treatment. At acidic pH, the emulsion stability increased with the increase in NaCl concentration but decreased at pH 7.0 and 9.0. Generally, at other pH ranges, the emulsion stability was decreased with increased heating temperature. The surface hydrophobicity showed the highest value at pH 2.0 and the lowest value at pH 11.0. As NaCl concentrationed, the surface hydrophobicity decreased at acidic pH. The NaCl concentration had no significant effects on surface hydrophobicity at pH 7.0, 9.0 except for the highest value observed at 0.8 M and 0.4 M. At all pH ranges, the surface hydrophobicity was increased, when the temperature increased. The foam capacity decreased, with increased in pH value. At acidic pH, the foam capacity was decreased with the increased in NaCl concentration. The highest value was observed upon adding 0.2 M or 0.4 M NaCl at pH 7.0 and 9.0. Heat treatments of $60^{\circ}C$ and $40^{\circ}C$ showed the highest foam capacity values at pH 2.0 and 4.5, respectively. At pH 7.0 and 9.0, the foam capacity decreased with the increased in temperature. The foam stability was not significantly related to different pH values. The addition of 0.4 M NaCl at pH 2.0, 7.0 and 9.0 showed the highest stability and the addition of 1.0 M at pH 4.5 showed the lowest. The higher the heating temperature, the lower the foam stability at pH 2.0 and 9.0. However, the foam stability increased at pH 4.5 and 7.0 before reaching $80^{\circ}C$.

• Journal of Animal Science and Technology
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• 제47권6호
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• pp.1033-1040
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• 2005

본 연구는 분리한 ovotransferrin의 식품소재로서의 단백질 특성과 병원성 미생물에 대한 항균능력을 측정하기 위해 실시하였다. 분리한 ovotransferrin의 수분 흡착력을 pH 3, 7, 11의 조건에서 살펴보았을 때 중성조건에서 다소 증가하는 경향을 보였지만 유의적인 차이는 없었다. 기포의 생성과 안정성은 산성조건인 pH 3에서 기포가 가장 적은 양이 발생되었고 시간이 지남에 따라 급속하게 사라지는 경향을 보였으며 중성조건인 pH 7에서는 기포의 감소의 폭이 적어 안정하게 유지됨을 보였다. 온도가 ovotransferrin의 기포의 발생과 안정성에 미치는 영향은 60℃에서 기포의 발생이 가장 높았으나 처리온도가 90℃ 이상이 되면 현저하게 감소하는 것으로 나타났다. Ovotransferrin의 항균 및 항 곰팡이 효과를 측정해 본 결과 농도에 따른 유의적인 저해효과는 없었으나 다만 25mg/ml의 농도로 처리하였을 때 E. coli, S. typhi, P. aerug와 Candida albican에서만 약한 저해 효과를 나타내었다. Albumin과 lysozyme을 ovotransferrin과 혼합사용이 항균 및 항 곰팡이 효과에 영향하는지를 알아본 결과 albumin과 ovotransferrin을 혼합사용 하였을 때 25mg/ml의 농도에서만 S. typhi와 candida albicans의 억제(++) 효과를 보였고 lysozyme과 ovotransferrin의 혼합사용은 12.5mg/ml의 농도에서만 S. typhi에서 약한 저해(+) 효과를 나타냈으며 candida albican에 대해서는 ++정도의 억제효과를 나타내었다. Ovotrnasferrin 자체의 항균 효과는 25mg/ml의 농도에서만 약한 저해효과를 보였으며 ovotransferrin의 항균 및 항 곰팡이 활성을 상승시키기 위한 lysozyme과 albumin의 역할은 그리 크지 않은 것으로 판단되었다.

• 대한화장품학회지
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• 제22권2호
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• pp.182-192
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• 1996

In this study, the relationship between wax matrix in lipstick and sweating was investigated by observing the change of size and shape of wax matrix with sweating by Scanning Electron Microscopy (SEM). For observation by SEM, a lipstick sample was frozen in liquid nitrogen, then the oil in the lipstick was extracted out in cold isopropanol($-70^{\circ}C$) for 1-3days. After isopropanol was evaporated, the sample was sputtered with gold, and examined by SEM. When examined the sweated sample by SEM, the change of wax matrix underneath the surface from fine, uniform structure to coarse, nonuniform structure was observed, which was resulted from the caking of surrounding wax matrix. That is, the oil underneath the surface was migrated to the surface of lipstick with sweating, consequently the wax matrix at that region was rearranged into the coarse matrix. In case of flamed lipstick, sweating was delayed and the wax matrix was much coarser than that of unflamed one. Its larger wax matrix at surface region was good for including oil. The effect of molding temperature on sweating was also studied. As the molding temperature was increased, sweating was greatly reduced and the size of wax matrix was increased. It was also found that sweating was influenced with the compatinility of wax and oil. A formula consisting of wax and oil which have good compatibility has a tendency of reduced sweating and increased size of wax matrix. When pigment was added to wax and oil. It was also found that sweating was influenced with the passage of time by observing a thick membrane of wax on surface of lipstick after a month from molding. In case of some lipsticks, the size of wax matrix was altered to bigger or smaller. In conclusion, the structure of wax matrix at the surface region of lipstick was changed with the process of foaming, molding temperature, compatibility of wax and oil, addition of pigment, and the passage of time. In most cases, as the size of wax matrix was increased, sweating was reduced and delayed.

• 동아시아식생활학회지
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• 제9권4호
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• pp.435-441
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• 1999

본 실험에서는 5$0^{\circ}C$, 10$0^{\circ}C$. 15$0^{\circ}C$. 20$0^{\circ}C$ 온도에서 20분간 가열하여 전처리한 참깨를 압착해서 참기름을 제거한 후 제조한 참깨 분리단백질의 항영양인자인 phytate와 phenolic acid의 함량의 변화와 식품학적인 기능적 특성을 검토하여 다음과 같은 결과를 얻었다. 참깨 분리단백질의 함량은 볶음 온도를 15$0^{\circ}C$로 상승시켰을 때 68.9%, 5$0^{\circ}C$에서의 65.5%에 비해 증가하였으나, 20$0^{\circ}C$에서는 64.1%로 오히려 감소하였고, 총페놀. 축합형 탄닌함량과 phytate함량 5$0^{\circ}C$에서 20$0^{\circ}C$로 볶음온도를 상승시에 유의적으로 증가하였다. 색도는 고온 처리한 참깨박 분리단백질은 L값과 b값은 유의적으로 감소하였고, a값은 20$0^{\circ}C$에서 처리한 경우에 증가하였다. 전반적으로 고온처리시에 짙은 갈색을 띄었으며, 겉보기 밀도와 지방 흡수력 그리고 수분 흡수력은 볶음 온도가 상승함에 따라서 유의적으로 증가하였다. 유화성은 5$0^{\circ}C$에서 15$0^{\circ}C$로 온도가 상승시에 증가하였지만 20$0^{\circ}C$에서 유의적으로 감소하였고, 기포성은 볶음온도에 따라 5$0^{\circ}C$와 10$0^{\circ}C$에서는 기포성의 감소가 크게 나타나지는 않았지만, 15$0^{\circ}C$와 20$0^{\circ}C$에서 현저하게 감소하였다. 기포안정성은 10$0^{\circ}C$에서 가장 높게 나타났으며, 20$0^{\circ}C$에서 볶아서 제조한 참깨 분리단백질에서 가장 낮게 나타났다.

• KSBB Journal
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• 제14권5호
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• pp.628-632
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• 1999

에리스리톨을 산업적으로 대량생산하기 위해서는 에리스리톨의 생산성을 높이고 부산물인 글리세롤의 생성을 억제하는 배지 및 발효 공정의 최적화가 필요하다. 에리스리톨 생성을 위한 최적 탄소원은 포도당이고 최적 농도는 400 g/L이며 최적 온도는 3$0^{\circ}C$였으며 이 때 산소는 과잉으로 공급해 주어야 함을 알았다. 에리스리톨의 수율과 생산성을 향상시키기고 배지가격을 줄이기 위해 효모 추출물의 사용을 5 g/L에서 3 g/L로 줄이고 urea 2.72g/L$K_2HPO_4$ 1.79 g/L, MgSO$_4$. $7H_2O$ 0.18 g/L를 첨가해 줌으로써 에리스리톨 수율을 31.4%에서 45.2%로 에리스리톨 생산성을 0.747 g/L/h에서 1.071 g/L/h로 향상시켰다. 또한 글리세롤의 생산량도 96.6 g/L에서 45.7 g/L로 줄었다. 이 최적 배지를 바탕으로 5L 발효기에서의 재현성과 pH에 대한 영향을 알아보기 위해 실험을 한 결과 pH를 조절한 경우에 에리스리톨 생산성이 낮아졌다. 5L 발효에서는 다량의 거품이 발생되는 것을 관찰하였다.

• 한국식품과학회지
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• 제20권6호
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• pp.762-768
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• 1988

우유의 지방분해 효소인 리파제를 분리 연구하기 위하여 홀몬처리 되지 않은 정상유와 홀몬 처리된 비정상유에서 리파제를 Heparin-Sepharose-CL-6B를 이용하여 분리 정제하였다. Heparin-Sepharose에 친화력을 조사한 결과 두 개의 효소활성이 있는 성분이 구분되었으며 한 성분은 Heparin-Sepharose-CL-6B에 결합되었고 다른 한 성분은 결합되지 않은 채 분리되었다. 친화성 크로마토그램에 결합되어 분리 정제된 리파제의 최적 온도, 최적 pH, 기질 특이성, 분자량 및 BSA의 활성제로서의 작용등 여러 가지 효소특성은 모두 동일한 것으로 나타났다. 그러나 홀몬처리된 소에서 얻은 우유의 경우에는 또 다른 호소활성 성분이 나타나 있음을 알았다. 이 lipolytic activity가 있는 성분은 Heparin-Sepharose-CL-6B에 친화력을 보이지 않았으므로 정상적인 milk lipase와는 구별된다. 따라서 홀몬처리된 소에서 얻은 우유에 함유된 성분중 Heparin-Sepharose에 결합된 효소는 유지방 자동산화에 영향을 끼치지 않으며 Heparin-Sepharose에 결합되자 않은 활성이 있는 성분은 자동산패에 영향을 크게 미친다고 볼 수 있다. 그 이유는 hormone의 불균형 상태로 인하여 생유에 자동산패가 일어날 수 있으며 이것은 비정상적으로 분비된 리파제 출현 사이에 연관관계가 있음을 의미한다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.645-649
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• 2009

Liquid desiccant cooling technology can supply cooling by using waste heat and solar heat which are hard to use effectively. For compact and efficient design of a dehumidifier, it is important to sustain sufficient heat and mass transfer surface area for water vapor diffusion from air to liquid desiccant on heat exchanger. In this study, the plate type heat exchanger is adopted which has extended surface, and hydrophilic coating and porous layer coating are adopted to enhance surface wettedness. PP(polypropylene) plate is coated by porous layer and PET(polyethylene terephthalate) non-woven fabric is coated by hydrophilic polymer. These coated surfaces have porous structure, so that falling liquid film spreads widely on the coated surface foaming thin liquid film by capillary force. The temperature of liquid desiccant increases during dehumidification process by latent heat absorption, which leads to loss of dehumidification capacity. Liquid desiccant is cooled by cooling water flowing in plate heat exchanger. On the plate side, the liquid desiccant can be cooled by internal cooling. However the liquid desiccant on extended surface should be moved and cooled at heat exchanger surface. Optimal mixing and distribution of liquid desiccant between extended surface and plate heat exchanger surface is essential design parameter. The experiment has been conducted to verify effective surface treatment and distribution characteristics by measuring wall side flow rate and visualization test. It is observed that hydrophilic and porous layer coating have excellent wettedness, and the distribution can be regulated by adopting holes on extended surface.

• 한국식품조리과학회지
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• 제6권3호통권12호
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• pp.9-15
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• 1990

Peanut prptein isolate was tested for the purpose of finding out the effect of pH, Sodium Chloride concentration and heat treatment on the solubility, surface hydrophobicity, foam expansion and foam stability. The solubility of peanut protein isolate was affected by pH and showed the lowest value at pH 4.5. When the peanut protein isolate was heated, the solubility decreased at pH 3 and pH 7 but at pH 9 solubility increased. At all pH range, solubility decreased as NaCl was added. The surface hydrophobicity of peanut protein isolate showed the highest value at pH 1.5. Generally, at acidic pH range the surface hydrophobicity was high, but at alkaline region, the surface hydrophobicity increased as the temperature increased. And when NaCl was added, the surface hydrophobicity was also increased. Foam expansion of peanut protein isolate was no significant difference among the values about pH. When the peanut protein was heated and NaCl was added, foam expansion was increased at pH 7. Foam stability was significantly low at pH 4.5 and foam stability was increased at acidic pH region below pH 4.5. At pH 7 and pH 9, heat treatment above $60^{\circ}C$ increased foam stability. When NaCl was added, foam stability was significantly increased at pH 3 and pH 7.

• 대한기계학회논문집B
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• 제24권7호
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• pp.938-944
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• 2000

Recently, micro fin tube is widely used to heat exchanger for high performance. And, as the alternative refrigerants for R-22, hydrocarbons such as R-290, R-600 and R-600a are very promising because of their low GWP and ODP. Thus, R-290 was used as working fluid in this study. Most design of heat exchanger had been based on heat transfer characteristics of pure refrigerant although refrigerant oil exists in the refrigeration cycles. So, the influence of oil on heat transfer characteristics have to be considered for investigating exact evaporation heat transfer characteristics. But, this is an unresolved problem of refrigeration heat transfer. Therefore the influence of the refrigeration oil to the evaporation heat transfer characteristics of R-290 were conducted in a horizontal micro tin tube. The mineral oil was used as refrigeration oil. The experimental apparatus consisted of a basic refrigeration cycle and a system for oil concentration measurement. Test conditions are as the follows; evaporation temperature $5^{\circ}C$, mass velocity 100 $kg/m^2s$, heat flux 10 $kW/m^2$, oil concentration 0, 1.3, 3.3, 5.7 wt.%, and quality $0.07{\sim}1.0$. When refrigeration oil was entered, oil foaming was observed at the low quality region. And, very small bubbles were observed as quality was increased. Pressure drop and heat transfer coefficient increased as the concentration of refrigeration oil increased to 5 wt.%.. The performance index of heat exchanger was the highest near 3.3 wt.%.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.43-44
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• 2023

Fire doors installed to prevent the spread of fire in buildings are made of paper honeycomb, glass wool, and other materials. Due to their high water absorption rate, they absorb ambient moisture and degrade, and their increased weight causes them to sag internally, creating voids that can warp in the event of a fire and allow flames to pass through. To overcome these issues, research is being conducted on the physical performance of lightweight aerated concrete. However, there is a lack of research on how to ensure fire resistance. Therefore, in this study, the backside temperature of lightweight aerated concrete formulations was measured and compared and analyzied with the physical performance. Since it is difficult to achieve low density by saturation alone, aerated concrete with EPS was produced, which resulted in a density reduction of 24'26%, but the strength increase per unit cement increase was 5'25%, which tended to be lower than the formulation without EPS. The results showed that the lightweight aerated concrete with EPS was 130~140℃ lower than the lightweight aerated concrete with EPS, which is believed to be due to the melting point of EPS delayed the heat diffusion. In the future, wo plan to conduct research to identify the optimal formulation for fire door core materials by varying the amount of EPS added and using industrial by-products to increase long-term strength.