• 한국식품과학회지
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• 제28권4호
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• pp.720-729
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• 1996

추청벼, 조생통일벼, IR 36등 세 품종의 쌀에 셀룰라제(cellulase) 처리가 팽윤력, 용해도, 아밀로그래프, differential scanning calorimetry (DSC), 가용성 탄수화물 용출 및 밥의 경도 등에 미치는 효과에 대하여 시험하였다. 효소처리에 의하여 세 품종의 쌀에서 모두 팽윤력과 용해도가 증가하였으며 아밀로그램 점도는 모두 감소하였다. 시차 주사 열량계(DSC)를 이용한 밥의 노화 시험에서는 효소 처리의 뚜렷한 효과가 없었다. 효소처리한 쌀의 가용성 탄수화물의 겔 크로마토그래피에서 분자량 10,000미만의 세포벽 분해산물이 확인되었다. Rheometer로 측정한 밥의 경도는 효소처리한 모든 품종의 쌀에서 감소하였다.

• Preventive Nutrition and Food Science
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• 제21권4호
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• pp.361-366
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• 2016

The physicochemical characteristics of fresh noodles made with blends of low-protein wheat flour and barley byproduct (BBP, $250{\mu}m$) were investigated. The crude protein contents (PC) of flour from Goso and Backjoong cultivars were 7.91% and 7.67%, respectively. PC and ${\beta}$-glucan contents from the BBP were 14.10% and 3.11%, respectively, which were higher than those in wheat flour. The water-holding capacity (WHC) of various blends was increased as a function of BBP but not gluten contents. Goso flour had the highest starch content (78.68%), with peak and final viscosities of 3,099 and 3,563 cp, respectively. Peak and final viscosities, trough, breakdown, and setback of the blends were decreased with the addition of BBP. Noodles made with Backjoong had the highest thickness score, while the hardness of noodles made with blends of Goso or Backjoong and 20% BBP were similar to those made from wheat flour only. The WHC of the samples was strongly correlated with PC, crude fiber, and ${\beta}$-glucan. The PC was not correlated with final viscosity, setback, thickness, hardness, gumminess, or chewiness.

• Korea-Australia Rheology Journal
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• 제13권4호
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• pp.189-196
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• 2001

The phase morphology is an important factor in the rheology of immiscible polymer blends. Through its size and shape, the interface between the two phases determines how the components and the interface itself will contribute to the global stresses. Rheological measurements have been used successfully in the past to probe the morphological changes in model blends, particularly for dilute systems. For more concentrated blends only a limited amount of systematic rheological data is available. Here, viscosities and first normal stress differences are presented for a system with nearly Newtonian components, the whole concentration range is covered. The constituent polymers are PDMS and PIB, their viscosity ratio can be changed by varying the temperature. The data reported here have been obtained at 287 K where the viscosities of the two components are identical. By means of relaxation experiments the measured stresses are decomposed into component and interfacial contributions. The concentration dependence is quite different for the two types of contribution. Except for the component contributions to the shear stresses there is no clear indication of the phase inversion. Plotting either the interfacial shear or normal stresses as a function of composition produces in some cases two maxima. The relaxation times of these stresses display a similar concentration dependence. Although the components have the same viscosity, the stress-component curves are not symmetrical with respect to the 50/50 blend. A slight elasticity of one of the components seems to be the cause of this effect. The data for the more concentrated blends at higher shear rates are associated with a fibrillar morphology.

• 한국자동차공학회논문집
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• 제19권3호
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• pp.130-137
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• 2011

Experimental investigations are conducted to figure out the feasibility of $Al_2O_3$ nanofluids as the alternative coolant for car engine. For the purpose, the thermal conductivities and viscosities of water/commercial coolant based $Al_2O_3$ nanofluids with 0.3, 1.0, 2.0 and 3.0 vol. % at temperatures ranging from $25^{\circ}C$ to $35^{\circ}C$ are measured. Thermal conductivities are measured using the transient hot-wire method and also viscosities are measured by Brookfield LVDV-III rheometer. Based on the results, it is shown that thermal conductivity of $Al_2O_3$ nanofluids with 3.0 vol. % is increased about 11% at $35^{\circ}C$ and the increment of viscosity approaches to 84% at shear rate of 600(1/s) and 80% at shear rate of 960(1/s) in the same temperature. with fundamental data for the thermal conductivity and viscosity of the nanofluids, the feasibility of $Al_2O_3$ nanofluids as the alternative coolant for car engine are discussed.

• 동아시아식생활학회지
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• 제18권1호
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• pp.58-63
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• 2008

This study was conducted to present fundamental data on the physicochemical properties and sensory qualities of salad dressings made with chicken foot gelatin. Preliminary experiments were performed to confirm the gelatin powder concentrations in preparing gelatin solutions. A 2% gelatin solution, including 0.5% agar, was prepared for use in the experiments that followed. Sensory evaluations were conducted to compare the organoleptic acceptance of dressings manufactured with differing concentrations of the additive in seasoning soybean sauce, mayonnaise, and sesame powder. The viscosities of the dressings significantly increased with increasing gelatin powder concentration. A decrease in turbidity was observed in the mayonnaise and sesame dressings. The color difference values of all dressings indicated no changes. In sensory evaluations of dressings prepared with gelatin solutions at different concentrations of 2 g (1%), 4 g (2%), and 8 g (4%) of gelatin powder, the 4 g (2%) sample received the highest score for overall acceptance. From this study, which was conducted to find an efficient use for chicken house wast product, it is anticipated that chicken feet will be utilized as a new raw material for producing collagen and gelatin, protein sources widely increasing in use with in the food and bio-industries.

• 대한화학회지
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• 제37권12호
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• pp.1003-1009
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• 1993

여러 온도와 압력에서 벤젠의 점성도를 결정하여, 액체 벤젠의 점성도에 미치는 온도와 압력의 영향에 대하여 연구하였다. 여러 온도와 압력으로 유지되고 있는 일정한 밀도의 벤젠 속에서 공 낙하 시간을 측정함으로써 벤젠의 점성도를 산출할 수 있었다. 그 결과로부터 벤젠의 비부피에 미치는 온도와 압력의 영향, 자유부피에 미치는 온도와 압력의 영향에 대해서 알아보았으며, 결론적으로 벤젠의 점성도에 대한 온도와 압력의 영향을 온도와 압력의 변화에 따르는 자유부피의 변화에 의하여 고찰하였다.

• 한국식품과학회지
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• 제22권1호
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• pp.66-70
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• 1990

sucrose-Nacl-물의 3성분 혼합액체의 점도를 예측하기 위한 모델을 결정하기 위하여 온도 $10{\sim}40^{\circ}C$, NaCl농도 $1.0064{\sim}5.7037mol$, sucrose농도 $0.3436{\sim}2.5966mol$의 범위에서 점도 실험을 행한 결과 다음의 결과를 얻었다. NaCl용액의 점도는 식 (8)로, sucrose용액의 점도는 식 (5)로 나타낼 수 있었다. 또한 식 (8)과 (5)의 계수들은 강한 온도의존성을 가지고 있었고 식 (7)로 표현되었다. NaCl-sucrose-물의 3성분 혼합액체의 점도는 5개의 계수를 가진 다항식인 식 (9)로 상당히 정확하게 표현할 수 있었고, NaCl용액과 sucrose용액 사이에는 상호작용은 거의 없는 것으로 생각되었다.

• 한국자기학회지
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• 제8권3호
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• pp.150-155
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• 1998

플라스틱 이방성 페라이트 자석에서 페라이트 분말함량 변화에 레올로지와 자기특성의 변화를 조사하였다. 분말함량 변화에 따른 상대점도의 측정값과 이론식을 비교하였다. 분말함량 증가에 따른 혼합물의 상대점도 증가경향과 플라스틱자석의 분말배향도의 감소경향은 정확히 일치하였다. 일정한 자장하에서 사출성형된 플라스틱 이방성 페라이트 자석에서 잔류자속밀도와 최대자기에너지적은 분말함량 증가에 따라 적선적으로 증가하다가 다시 감소하여 극대값을 나타냈으며, 극대값 이후의 자기특성 가소는 분말배향도의 급격한 감소에 기안하였다. 자기특성 극대값을 나타내는 분말한량은 사출형성시 자장의 세기와 결합체의 용융점도에 의존하며, 높은 자기특성을 위해서는 낮은 용융점도의 결합제 사용이 필요하다.

• Elastomers and Composites
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• 제53권3호
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• pp.141-149
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• 2018

A series of aromatic poly(o-hydroxyamide)s (PHAs) were synthesized by the direct polycondensation reaction of 4,4′-(2,3-quinoxalinedioxy) dibenzoic acid and/or 4,4′-(2,3-pyridinedioxy) dibenzoic acid with bis(o-aminophenol) including 2,2-bis-(amino-4-hydroxyphenyl)hexafluoropropane. The PHAs exhibited inherent viscosities in the range of 0.17-0.35 dL/g at $35^{\circ}C$ in a DMAc solution. These polymers showed low inherent viscosities and yielded brittle films. All the PHAs showed excellent solubility in aprotic solvents such as DMAc, DMSO, NMP, and DMF at room temperature and in less polar solvents such as pyridine and THF. However, all the PBOs were only partially soluble in $H_2SO_4$. The PBOs exhibited 10% weight loss at temperatures in the range of $537-551^{\circ}C$. The maximum weight loss temperature increased with an increase in the content of the quinoxaline-containing monomer. The residue of the PBOs showed a weight loss of 45.8-56.7% at $900^{\circ}C$ in a nitrogen atmosphere.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.369-369
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• 2003

Viscarin is a tradename given to viscosifying carrageenans manufactured by FMC BioPolymer. The suitability of Vis car ins as rheology agents in mild cleansing applications has been investigated. Rheological properties, foam volume and clarity were measured to determine the impact of including 1 % Viscarin on 10% solutions of the following surfactants: acylglutamate, cocoamidopropyl betaine, PEG-80 laurate, sodium lauryl sulphate and sodium lauryol sarcosinate. Viscosity, pseudoplasticity and thixotropy of Viscarin/surfactant solutions varied with surfactant type. In all cases, the addition of Viscarin substantially increased viscosity. For example, at a shear rate of 1 sol, all surfactant solutions had viscosities <0.1 Pa s while viscosities of Viscarin/surfactant solutions ranged from 10 to 60 Pa s. By comparison, a solution of 1 % Viscarin had a viscosity of 0.3 Pa s. Clarity of surfactant solutions decreased in all cases on the addition of Viscarin. However, it was found that by including a mild solubilizing surfactant, such as PEG 40 hydrogenated castor oil, crystal clarity could be maintained in Viscarin/surfactant solutions. Viscarin increased the foam volume of sodium lauryolsarcosinate solutions from 10 ml to 220 ml and had no impact on the foam volume of the other surfactants tested. These results were used to formulate a clear, ultra-mild foaming cleansing gel based on sodium lauryol sarcosinate and Viscarin without the need for a secondary, foam-boasting surfactant. A mild shampoo was also formulated. Both products have excellent skin-feel and are capable of suspending bubbles and solid inclusions.