• Fibers and Polymers
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• v.6 no.2
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• pp.131-138
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• 2005

A theoretical model is proposed in order to investigate rheological behavior of bubble suspension with large deformation. Theoretical constitutive equations for dilute bubble suspensions are derived by applying a deformation theory of ellipsoidal droplet [1] to a phenomenological suspension theory [2]. The rate of deformation tensor within the bubble and the time evolution of interface tensor are predicted by applying the proposed constitutive equations, which have two free fitting parameters. The transient and steady rheological properties of dilute bubble suspensions are studied for several capillary numbers (Ca) under simple shear flow and uniaxial elongational flow fields. The retraction force of the bubble caused by the interfacial tension increases as bubbles undergo deformation. The transient and steady relative viscosity decreases as Ca increases. The normal stress difference (NSD) under the simple shear has the largest value when Ca is around 1 and the ratio Of the first NSD to the second NSD has the value of 3/4 for large Ca but 2 for small Ca. In the uniaxial elongational flow, the elongational viscosity is three times as large as the shear viscosity like the Newtonian fluid.

• Korean journal of food and cookery science
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• v.33 no.1
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• pp.87-93
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• 2017

Purpose: Rice starch is known not to be suitable to Mook. Its gel is not hard and elastic enough and too sticky. This study investigated the effects of agar, carrageenan, and gelatin addition on low amylose rice flour paste and gel properties for making Mook. Methods: Angemi, low amylose rice, and Goamibyeo, intermediate amylose rice, were dry milled. The properties of Mook were determined by texture profile analysis (TPA), cold storage stability, and sensory acceptance. Results: Addition of agar and carrageenan increased cold paste viscosity, whereas addition of gelatin decreased cold paste viscosity while improving breakdown and setback viscosity. When 30% of gelling agents such as agar, carrageenan, and gelatin were added to low amylose rice, Angemi, Mook-like gels were formed. The hardness, adhesiveness, and springiness of gelling reagent-added Angemi Mook increased, whereas cohesiveness decreased, and fracturability was not observed. The addition of gelling agent decreased lightness and increased yellowness. Angemi Mook added with gelatin showed the best freeze-thaw stability while addition of agar and carrageenan increased syneresis. The carrageenan-added Angemi Mook was equal to Goamibyeo 100% Mook in all sensory acceptance properties without significant difference. Conclusion: Above results suggest that addition of carrageenan and gelatin to low amylose rice can be used to produce Mook with improved physical properties.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.261-264
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• 2004

In this study, the experiment was carried out to investigate and analyze the strenth properties and flowability of ultra-high strength concrete accroding to types of mineral admixtures and cements. The main experimental variables were water/binder ratio $25.0\%$, water content $160kg/m^3$ and mineral admixtures such as fly ash, silica fume and meta kaolin. According to the test results, the principle conclusions are summarized as follows 1) In case of using admixtures, superplasticizer amount need more than plain concrete. 2) According to kinds of admixtures and cements, the viscosity of concrete show much difference. 3) The autogeneous shrinkage of ultra-high strength concrete is profitable that use admixture, and heat of hydration is desirable that apply considering countermeasure enough in the advance. 4) Meta kaolin is excellent in side but has viscosity enlargement efficiency a little. But, problem estimates that is not to make design strength to and $70N/mm^2$ if use mixing condition with water-binder ratio properly.

• Preventive Nutrition and Food Science
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• v.4 no.3
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• pp.180-183
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• 1999

Seaweeds is a rich sources of dietary fibers exerting a number of physiological properties. However, the reported dietary fiber contents of seaweeds are not consistent and vary widely. Also. a limited number of studies on the biological effects of specific seaweeds have been reported. In this study, water-holding capacity, viscosity and antixidantive activity of major dietary seaweeds were measured to assess their physiological effects. Results showed that total dietary fiber contents ranged from 28 to 51% of dried weight, and large proportions of dietary fiber were insoluble fibers. Water-holding capacity was highest in sea mustard being 1310% , while laver, sea tangle, and green laver exhibited 943, 854 and 815%, respectively. The viscosity of seaweed samples was 20 to 40 cP in sea mustard and sea tangle, while laver and green laver possessed much lower values. All seaweed samples revealed a weak, albeit significant electron donating ability. Also, lipid peroxidation was reduced by 7 to 18%. However, there was no difference in antioxidative activity among seaweeds and sample concernations used. These results imply that most commonly used seaweeds possibly exert parts of their physiological effects through their water-holding, gel-forming , and/or antioxidative activities.

• Journal of the Korean Society of Food Culture
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• v.24 no.4
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• pp.433-439
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• 2009

The purpose of this study was to investigate the quality characteristics of tomato sauce, which is widely used in Western cuisine, according to tomato variety. The plum tomato sauce treatment had the highest pH at 4.13 while sauces made with Seo gwang and Young gwang tomatoes exhibited the lowest pH level of 4.07 (p<0.05). Sweetness was highest in the plum tomato sauce at $9.80^{\circ}$Brix. This might have been due to the fact that the plum tomato variety was the sweetest among the different tomatoes. There were no significant differences among the treatments in terms of reducing sugars, salinity, or viscosity. A color difference analysis indicated that redness (a-value) was highest in the plum tomato sauce, which contained a high level of lycopene. Sensory evaluations were performed by 15 professional panelists with scoring tests for color, flavor, taste, aftertaste, viscosity, and overall acceptability. The plum tomato sauce received the best scores in every evaluation, except for viscosity. These comparative results will support the development of better quality tomato sauce using plum tomatoes.

• Journal of Oral Medicine and Pain
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• v.19 no.2
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• pp.25-45
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• 1994

The purposes of this study were to investigate the effect of pilocarpine-containing chewing gum for the treatment of xerostomia and to compare the effect of pilocarpine-containing chewing gum with that of pilocarpine oral administration. The 20 subjective and objective xerostomic patients were included in this study and divided into 3 groups. Five subjects were included in gum base chewing group, 10 in pilocarpine-containing gum chewing, and 5 in pilocarpine oral administration. The author measured unstimulated whole salivary flow rate, stimulated parotid salivary flow rate, pH of resting whole saliva, viscosity of stimulated whole saliva, and subjective symptoms and discomforts using VAS(visual analogue scale) at the beginning of the experiment. And the author investigated the changes of these factors at 1, 2, 3, and 4 week after. The obtained results were as follows : 1. There were significant increases in the unstimulated whole salivary flow rate in pilocarpine-containing gum chewing and pilocarpine oral administration groups. But there was no significant difference between pilocarpine-containing gum chewing and pilocarpine oral administration groups. 2. There was a significant increase in the stimulated parotid salivary flow rate in pilocarpine- containing gum chewing group. But there was no significant difference between pilocarpine- containing gum chewing and pilocarpine oral administration groups. 3. The change of salivary pH showed the increasing pattern in all groups. But there was no significant difference among groups. 4. There were no significant changes in the values of salivary viscosity in all groups through the experimental period. 5. There were significant decreases of VAS(visual analogue scale) in the degree of subjective symptoms and discomforts in pilocarpine-containing gum chewing and pilocarpine oral administration groups. But there was no significant difference between pilocarpine- containing gum chewing and pilocarpine oral administration groups.

• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.690-697
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• 2017

In this study, styrene-isoprene-styrene (SIS)-styrene-butadiene-styrene (SBS) modified asphalt was prepared for waterproof-sheet to measure its properties including softening point, penetration, low temperature flexibility, viscosity and adhesion. Then the properties of SIS-SBS modified asphalt imparted with self-healing were optimized to seek for optimal compositions of SIS and SBS versus asphalt according to response surface methodology (RSM). As the content of SBS or SIS was increased, both properties of softening point and viscosity, measured at high temperature, were increased with a statistical significance. However, the increments of softening point and viscosity per unit content of SBS added, were observed to be greater than those per unit content of SIS added, respectively. It was due to the difference of thermal properties of SBS and SIS at high temperature that the cross-linking degree of SBS was increased by gelation accompanied with the increase of viscosity, while chain-entanglement of SIS was relatively reduced owing to a chain scission of poly(isoprene) blocks causing the decrease of viscosity. To the contrary, SIS-SBS modified asphalt showed a behavior of the least elasticity resulting in both the maximum of penetration and adhesion, measured at room temperature, as well as the lowest low temperature flexibility at the composition of SIS, 4 g and SBS, 8.5 g based on asphalt, 63 g.

• Culinary science and hospitality research
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• v.22 no.2
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• pp.29-43
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• 2016

Pesto were prepared with five different nuts including pine nut, sunflower seed, pumpkin seed, walnut and almond to examine the antioxidant properties(total polyphenols, total flavonoids, electron donating ability) and sensory test(attribute difference, acceptance). Pesto were measured based on color value, pH, viscosity, total cell numbers for 0, 5, 10, 15 and 20 days at $4^{\circ}C$. The higher total phenol and total flavonoid content of pesto added with various nuts was higher antioxidant capacity. Basil pesto added with sunflower seeds and walnuts were considered to be more functional more than pine nuts addition. The attribute difference test results was the color intensity, nut taste, bitter taste, coarseness, oily taste, thickness were evaluated significant difference kinds of nuts. Gloss, basil flavor, nuts flavor, basil taste were not evaluated significant difference in kind of nuts. The preference test results reveal that the appearance, taste, texture and overall preference level was the highest in PNP(pinenut pesto) and SSP(sunflower seed). L value, pH, decrease while a value, b value and viscosity increased as kind of nuts in during storage. Total cell number increased and then decreased a little at a certain point. When prepared pesto, SSP(sunflower seed) was the highest in antioxidant property, and change of color value, pH, viscosity, total cell number were the lowest. In addition to the use of pine nuts, sunflower seeds have been identified are possible.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.331-331
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• 2017

This study was conducted to know the influence of air temperature and sunshine duration on yield, chemical component, pigment color difference and starch characteristics of two colored rice cultivars in the plain area of Yeongnam province in Korea. The $L^*$, $a^*$, and $b^*$ value of brown rice in Hongjinju and Josaengheugchal rice cultivars was significantly different at continuous cultivated years, 2015 and 2016. The $L^*$, $b^*$ value of two colored rice was significantly increased in 2016 compared to 2015. The $a^*$ value of Josengheugchal rice cultivar was also significantly higher at 2016 than at 2015. It can be noticed the $a^*$, $b^*$, $L^*$ values in Josaengheugchal varied more than those in Hongjinju. Air temperature during ripening period in 2016 was higher than 2015, especially minimum temperature was too high to proper maturation for rice quality. In Josaengheugchal rice cultivar, sunshine duration after heading was longer in 2016 than in 2015. On the contrary, Hongjinju rice cultivar was ripened under condition of insufficient sunshine duration in 2016. The short growing duration by high temperature and long shiny duration made the lack of pigment for Josaengheugchal brown rice. In Hongjinju rice cultivar, shorten sunshine duration and higher night temperature were the source of the pigment deficiency. The grain size of rice which produced in 2016 was bigger than that of 2015 in both rice cultivars. The 1,000 grain weight of rice from 2016 was also bigger than that of 2015. Head rice ratio was high in the rice cultivars produced in 2015. Protein of milled rice in 2016 was more decreased than that of 2015 in Josaengheugchal rice cultivar, it showed reverse result in Hongjinju rice cultivar. Amylose contents of milled rice in 2016 were more decreased than that of 2015 in Hongjinju rice cultivar. Branch chain length distribution of amylopectin was shown a distinct difference between Josaengheugchal and Hongjinju rice flours by each produced year. Josaengheugchal rice cultivar produced in 2015 had a higher amount of short chains than that of 2016 rice starches. In Josaengheugchal rice cultivar, the pasting temperature and peak, trough, breakdown, final viscosity increased in rice flour which produced at 2016, whereas the setback viscosity and peak time showed lower value than those of rice from 2015. The most pasting properties (except of setback viscosity) of rice starch in Hongjinju rice cultivar grown in 2015 were higher than those of rice cultivar produced in 2016.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.1
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• pp.18-25
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• 1984

The transition boiling of a liquid droplet on a heated flat surface was studied utilizing Kotake's model with the effects of viscosity of a thin vapor layer between the droplet and the hot plate taken into account. This problem was analyzed considering the process of the droplet evaporation which resulted in hydrodynamic instability at the liquid-vapor interface. The results of the study are as follows; (1)The effect of the viscosity in the vapor layer at the interface appears as a dimensionless number N, namely .sigma. .delta.$_{0}$ /.rho.nu.$^{2}$ (2)The time required for evaporation at the transitional region increases with the temperature difference ratio .DELTA. T$_{r}$. The rate of increase of the total evaporation time becomes larger as increasing of N$_{m}$(N number at maximum heat flux) increases.s.