• Title/Summary/Keyword: Viscosities

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The Effect of Cellulase Treatment on the Physicochemical Properties of Rice and the Texture of Cooked Rice (Cellulase 처리가 쌀의 이화학적 특성 및 밥의 텍스쳐 특성에 미치는 영향)

  • Kim, Young-Kyung;Ahn, Seung-Yo
    • Korean Journal of Food Science and Technology
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    • v.28 no.4
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    • pp.720-729
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    • 1996
  • Effect of the cellulase treatment on the physicochemical properties of three varieties of rice (chucheongbyeo, chosengtongilbyeo and IR 36) and the texture of cooked rice were investigated. The swelling power and solubility of the rice flours were increased and amylographic viscosities, especially cold viscosities were decreased by cellulase treatment in all varieties. Gel chromatography of soluble carbohydrates from cellulase-treated rice flours on sepharose 2B-CL showed a singificant increase of low molecular weight $(10^{4})$ fraction which might be produced upon hydrolysis in endosperm cell wall constituents. The hardness of cooked rices prepared from cellulose-treated rices significantly decreased.

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Effects of Blends of Low-Protein Winter Wheat Flour and Barley Byproducts on Quality Changes in Noodles

  • Lee, Na-Young
    • Preventive Nutrition and Food Science
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    • v.21 no.4
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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.

Rheology and morphology of concentrated immiscible polymer blends

  • Mewis, Jan;Jansseune, Thomas;Moldenaers, Paula
    • Korea-Australia Rheology Journal
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    • v.13 no.4
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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.

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Thermal Conductivity and Viscosity of Distilled Water/Commercial Coolant Based $Al_2O_3$ Nanofluids (증류수-부동액 혼합 $Al_2O_3$ 나노유체의 열전도도와 점성계수)

  • Kwon, Hey-Lim;Hwang, Kyo-Sik;Jang, Seok-Pil
    • Transactions of the Korean Society of Automotive Engineers
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    • v.19 no.3
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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.

A Study on the Characteristics of Salad Dressings Containing Chicken Foot Gelatin (닭발 추출 젤라틴을 이용한 샐러드 드레싱의 품질 특성)

  • Shin, Mee-Hye;Kim, Jong-Goon;Kang, Kun-Og
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.1
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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.

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Effect of Temperature and Pressure on the Viscosity of Benzene (벤젠의 점성도에 대한 온도와 압력의 영향)

  • Jeong Rim Kim;Jin Burm Kyong;Mi Hyun Lew
    • Journal of the Korean Chemical Society
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    • v.37 no.12
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    • pp.1003-1009
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    • 1993
  • The viscosities of benzene have been determined at several temperatures and pressures to investigate the effect of temperature and pressure on the viscosity of benzene in liquid phase. When a falling ball viscometer with a constant volume contained a given amount of liquid benzene at desired temperatures and pressures, the viscosities of benzene in the viscometer could be evaluated from the measurements of the falling time of a skinker. The variations of the specific volume and the free volume of liquid benzene with temperature and pressure were, from the results, searched out. Finally, the effects of temperature and pressure on the viscosity of benzene were discussed by means of the variations of free volume with temperature and pressure.

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Viscosities of Ternary Mixtures of Sucrose-Sodium Chloride-Water (Sucrose-NaCl- 물의 3성분 혼합액체의 점도에 관한 연구)

  • Oh, Myung-Suk
    • Korean Journal of Food Science and Technology
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    • v.22 no.1
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    • pp.66-70
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    • 1990
  • Correlations have been developed for estimating the viscosities of ternary mixtures of sucrose-sodium chloride-water over a temperature range of $10-40^{\circ}C$ and a concentration range of 1.0064-5.7037 molality sodium chloride and 0.3436-2.5966 molality sucrose. The viscosity data of sodium chloride and sucrose solutions have been fitted very well utilizing proposed polynomial equation, respectively and the temperature dependence analysis for sodium chloride and sucrose solutions showed that 1/T dependence is accurate. The experimental viscosity data for surose-sodium chloride-water mixtures were fitted to a five parameter polynomial with a goodness of fit approximating experimental error and it seems that there is no significant Interaction between sodium chloride and surose solutions.

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Rheological and Magnetic Properties of Plastic Ferrite Magnets (플라스틱 페라이트 자석의 레올로지와 자기특성)

  • 이석희;최준환;문탁진;정원용
    • Journal of the Korean Magnetics Society
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    • v.8 no.3
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    • pp.150-155
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    • 1998
  • The purpose of this study is to investigate the variations of rheological and magnetic properties with powder loading in plastic anisotropic ferrite magnets. The measured relative viscosities with powder loading were compared with the calculated ones. The variation of relative viscosities with powder loading was in good agreement with that of particle alignment. Remanent flux density and maximum energy product increased linearly with the increase of powder loading, and then showed maximum values. The decrease of magnetic properties at high powder loading was caused by rapid decrease of particle alignment due to the drastic increase of mixture viscosity. The powder loading for maximum magnetic properties is dependent on magnetic field during injection molding and melt viscosity of binder, so the binder with low melt viscosity is necessary to fabricate the magnet with high properties.

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Synthesis and Thermal Properties of Wholly Aromatic Poly(benzoxazole)s

  • Han, So Hee;Lee, Eung Jae;Choi, Jae Kon
    • Elastomers and Composites
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    • v.53 no.3
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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.

Carrageenan as a Rheology Agent for Mild Cleansing Applications.

  • Lynch, Gerard
    • Proceedings of the SCSK Conference
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    • 2003.09b
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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.

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