• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.6
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• pp.612-616
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• 1990

The addition of water into oil phase containing hydrophobic emulsifier while stirring forms W/O emulsions. When dispersed phase increase up to a certain extent, phase inversion into O/W emulsions occurs and just before phase inversion O/W/O emulsions exist in a mixed state with W/O emulsions. Thus this experiment was carried out to examine O/W/O emulsions formation in W/O emulsions. The viscosity of sample emulsions(water phase： $H_2O$, oil phase : TGCR-containing olive oil) was measured at the shear rate of 1.92 to 384 per second and at temperature of 25$\pm$0.1$^{\circ}C$, and the development of O/W/O emulsions evaluated from the difference between theoretical and measured values by substituting measured value for Mooney's equation. The formation of O/W/O emulsions tended to be high in sample emulsions just before phase inversion and increase with decreasing TGCR concentrations. This result suggests that high viscosity observed right before phase inversion may also be caused by the formation of O/W/O emulsions.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.384-390
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• 2008

This study examined the effects of sprouted brown rice (SR), gluten (G), and hydroxypropyl-methyl-cellulose (H) on the suppression of retrogradation in breads made with Korean wheat flour. An amylograph was used to determined the pasting properties of dough samples made with Korean wheat flour and additions of SR, SR+G, SR+H, and SR+G+H, respectively. In addition, a texture analyzer was employed to measure the hardness changes of bread samples left at room temperature for 72 hours. Finally, the type of retrogradation was calculated by the Avrami equation. The results showed that the addition of SR significantly decreased dough viscosity. However, the dough samples containing SR, G, and H all displayed reduced cold paste viscosity and setback, indicating a suppression of staling. The bread samples containing SR added to Korean wheat flour had increased hardness, but the addition of gluten (SR+G) reduced hardness. Upon examining the bread samples stored at room temperature for 24 hours, it was shown that the addition of G and H with SR (SR+G+H) suppressed retrogradation. Finally, the Avrami model data indicated that the type of retrogradation varied according to the addition of SR, G, and H. The breads made with hard wheat flour (HWF), WM, and WM+SR+H had similar Avrami exponents ($1.20{\sim}1.28$), while those for WM+SR, WM+SR+G, and WM+SR+G+H ranged from 2.7 to 3.3. Overall, the combined addition of SR and H was considered effective for preventing retrogradation in bread made with Korean wheat flour.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.383-388
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• 1985

Soy protein isolate was acylated with succinic anhydride and acetic anhydride. The functional properties are markedly improved by acylation of the $\varepsilon$-amino groups. Acylation of the available amino groups shifted the isoelectric point from 4.5 to 4.0 and enhanced the solubility between pH 4.0-6.0. In the 0.03M-$CaCl_2$ solution the solubility of the modified soy protein is much larger than that of the unmodified protein above the isoelectric point. The emulsion properties and foaming properties also improved by the modification and the effects of pH on the properties paralleled its effect on protein solubility. The changes of reduced viscosity with concentration followed Huggin's equation and by modification the intrinsic viscosity of the soy protein increased and the interaction coefficient decreased.

• Journal of the Korean Geosynthetics Society
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• v.5 no.2
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• pp.1-8
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• 2006

The properties of contaminated soil, contaminants and elapsed time are important considering factors to in-situ soil remediation. Gabr et. al. (1996) derived the solution equation of contaminant concentration ratio as initial one ($C/C_0$) with time and spatial changes in contaminated area which are embedded with vertical drains. The contaminant concentration ratio ($C/C_0$) is analyzed with time and spatial changes as varying the effective diameter, porosity, shape factor, density of contaminated soil, temperature in ground, unit weight and viscosity of contaminants by using FLUSH1 model modified from FLUSH. Results from numerical analysis indicate that the most important factor to the in-situ soil remediation in vertical drain system is the effective diameter of contaminated soil. It also shows that the next important factors are the viscosity of contaminants, porosity of soil, shape of soil, temperature in ground, unit weight of contaminants and density of soil, in order. However, the others except the effective diameter of contaminated soil are insignificant to the soil remediation.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.150.1-150.1
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• 2014

Showerhead is used as a main part in the semiconductor equipment. The face plate flatness should remain constant and the cleaning performance must be gained to keep the uniformity level of etching or deposition in chemical vapor deposition process. High operating temperature or long period of thermal loading could lead the showerhead to be deformed thermally. In some case, the thermal deformation appears very sensitive to showerhead performance. This paper describes the methods for robust design using computational fluid dynamics. To reveal the influence of the post distribution on flow pattern in the showerhead cavity, numerical simulation was performed for several post distributions. The flow structure appears similar to an impinging flow near a centered baffle in showerhead cavity. We took the structure as an index to estimate diffusion path. A robust design to reduce the thermal deformation of showerhead can be achieved using post number increase without ill effect on flow. To prevent the showerhead deformation by heat loading, its face plate thickness was determined additionally using numerical simulation. The face plate has thousands of impinging holes. The design key is to keep pressure drop distribution on the showerhead face plate with the holes. This study reads the methodology to apply to a showerhead hole design. A Hagen-Poiseuille equation gives the pressure drop in a fluid flowing through such hole. The assumptions of the equation are the fluid is viscous-incompressible and the flow is laminar fully developed in a through hole. An equation can be expressed with radius R and length L related to the volume flow rate Q from the Hagen-Poiseuille equation, $Q={\pi}R4{\Delta}p/8{\mu}L$, where ${\mu}$ is the viscosity and ${\Delta}p$ is the pressure drop. In present case, each hole has steps at both the inlet and the outlet, and the fluid appears compressible. So we simplify the equation as $Q=C(R,L){\Delta}p$. A series of performance curves for a through hole with geometric parameters were obtained using two-dimensional numerical simulation. We obtained a relation between the hole diameter and hole length from the test cases to determine hole diameter at fixed hole length. A numerical simulation has been performed as a tool for enhancing showerhead robust design from flow structure. Geometric parameters for the design were post distribution and face plate thickness. The reinforced showerhead has been installed and its effective deposition profile is being shown in factory.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.1 s.20
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• pp.83-95
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• 2006

This study aims to analysis of suspended-load concentration in related to those data by measuring vertical sediments distribution with rainfall using the ASM (Argus Surface Meter)- IV at the channel reach of a upstream and a downstream in small river. The watershed, small river basin where had taken for experimental study was selected, which is a drainage area lied at Walha in Yunkee-Gun, Chungnam Province. Measured data of suspended-load concentration consists of two groups with 2,145 data during 1hr 11min 30sec and 1,216 data during 40min 32sec for measuring time of 2 second in the study reaches at river, respectively. In order to analyze of the vertical concentration distribution, using the data sets are selected the measuring time 16 sets one of these data by random in the study reaches. As a results, the Rouse number of a measured and a calculated value show that a rang of $0.00129{\sim}0.02394$, averaged value of 0.01129 md, a rang of $0.00118{\sim}0.00822$, averaged value of 0.00436 in upstream reaches, and also a rang of $0.065115{\sim}0.065295$, averaged value of 0.06521, and a rang of $0.057315{\sim}0.059109$, averaged value of 0.05795 in downstream reaches, respectively. These difference show that measured Rouse number compared with downstream reach errors of less than in upstream reach, but between measured and calculated of the Rouse number compared with downstream reach errors of more than in upstream reach, respectively. It seems to will be included one of the occurrence errors of variable estimations when Rouse number of calculated value to be made computed by the fall velocity with a high temperature of water using equation of empirical kinematic viscosity was derived in this study.

• Food Science and Preservation
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• v.13 no.5
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• pp.555-562
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• 2006

This study was conducted to investigate the rheological properties of protein-bound polysaccharide powders (SD-1, 2, 3) using ultrafiltration (UF) and spray drying (SD) process from Agaricus blazei Murill. The calculated weight-average molar mass (Mw) in the positions at 29.7 mL (for SD-1), and at 27.8 mL (for SD-2), and at 18.7 mL (for SD-3) was $8.2{\times}10^3,\;9.6{\times}10^4$, and $5.9{\times}10^6g/mol$, respectively. As concentration increased the solution showed higher pseudoplasticity where the pseudoplasticity decreased as temperature increased. The flow behaviors of spray dried powder solutions were more fitted to Herschel-Bulkley equation than Power law equation. Apparent viscosity of SD-2 was more temperature-dependent than that of SD-1 and 3. However, the SD-3 tended to be more concentration-dependent than SD-1 and 2 as temperature increasing.

• Korean Journal of Microbiology
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• v.45 no.1
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• pp.63-68
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• 2009

The exo-polysaccharide producing microorganism, Aureobasidium pullulans IMS-822, was isolated and identified from soil. The viscosity-average molecular weight of exo-polysaccharide was calculated as $8.9{\times}10^5$ by Mark-Houwink equation. The sugar component of exo-polysaccharide was determined as glucose by HPLC analysis. The IR spectra indicated that the exo-polysaccharide has an absorption peak at 890 $cm^{-1}$ for the ${\beta}-configuration$ of D-glucan. The $^{13}C$ NMR signal at ${\delta}$ 86.62 ppm arose from the substituted C-3 of glucose. The signal at ${\delta}$ 72.11 ppm was assigned to C-6 of branched ${\beta}-(1{\to}3)-D-glucosyl$ residues. Viscosity and Congo red reaction indicated that {\beta}-(1{\to}3)(1{\to}6)-glucan$ produced by A. pullulans IMS-822 has a highly ordered hydrogen-bond dependent conformation in aqueous solution, which collapses in strong alkaline solution.

• Applied Chemistry for Engineering
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• v.25 no.2
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• pp.209-214
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• 2014

In this paper, the rheological behaviors and non-Newtonian characteristics of maltenes which is effected by hydrocarbon solvent type, solvent mixing ratio, temperature and shear rate was measured and compared with oil sands bitumen. Maltenes was made by SDA (solvent deasphalting) method from oil sands bitumen. Oil sands bitumen had apparent viscosities of $800{\sim}150000mPa{\cdot}s$ measured at a shear rate of $50sec^{-1}$ in the range of $25{\sim}85^{\circ}C$ and showed yield stress of 0.1~0.3 Pa at the temperatures below $35^{\circ}C$. All the oil sands bitumen and maltenes exhibited a shear-thinning, i.e. pseudoplastic behavior and apparent viscosity of maltenes decreased with decreasing carbon numbers of hydrocarbon solvent. The change in apparent viscosity with temperature could be described by the simple Guzman-Andrade equation, and maltene viscosities were decreased as the mixing ratio of n-pentane was raised. Also, all maltenes approached to Newtonian fluid as temperature were increased. the degree of pseudoplasticity was enhanced with decreasing carbon number of solvent.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.645-650
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• 2001

A study was carried out to establish the detection method for irradiated cereals. Cereals were ground and irradiated at 2.5, 5.0, 7.5, 10, 15 kGy using a $Co^{60}$ irradiator. The viscosities decreased in all samples by increasing irradiation dose. The viscosity of the Panicum millaceum (Korean) and Andropogon sorghum (Korean) paste dropped from $143.38{\pm}0.44$ and $35.92{\pm}1.90$ in the control to $6.60{\pm}1.16$ and $3.86{\pm}0.32$, respectively, in the samples irradiated at 15 kGy. These trends were similar to samples from china. Regression equation and coefficients of viscosity of Panicum millaceum (Korean and China) and Andropogon sorghum (Korean and China) were 0.80 (y=-27.789x＋150.17), 0.98 (y=-3.367x＋88.93), 0.84 (y=-6.0466x＋35.49) and 0.84 (y=-13.346x＋101.67) at 50 rpm. All samples resulted in a decrease in specific parameter by increasing rpm after irradiation. Parameter values showed dose-dependent relationship between unirradiated and irradiated samples and indicated that all values of unirradiated samples were higher than the irradiated ones. These results suggest that the detection of irradiated cereals at various doses using viscometric methods is possible.