• 한국신재생에너지학회:학술대회논문집
• /
• 2008.10a
• /
• pp.254-257
• /
• 2008

For crystalline slags, of which the viscosity rapidly increases at $T_{cv}$ due to the formation of crystalline phases, the Tcv is affected by measurement conditions. In this study, we investigated the effect of cooling rate, and alumina dissolution on the determination of $T_{cv}$. Using synthetic slag samples based on the composition of Alaska Usibelli slag, $T_{cv}$ were determined under a constant cooling rate of $2^{\circ}C$/min, and under rapid cooling with holding time to allow the slag to reach thermal and rheological equilibrium. The effect of alumina dissolution was investigated using platinum lined crucibles. The constant cooling resulted in lower $T_{cv}$ by $33^{\circ}C$ as compared to the equilibrium measurements. Under $2^{\circ}C$/min cooling, the blocking alumina dissolution resulted in lower $T_{cv}$ by $23^{\circ}C$. When the $T_{cv}$ was measured under $2^{\circ}C$/min cooling using an alumina crucible, therefore, the effects of a constant cooling is somewhat offset by the alumina dissolution effect, and bring the measured value closer to the true value.

• The Korean Journal of Food And Nutrition
• /
• v.12 no.3
• /
• pp.252-257
• /
• 1999

In an attempt to evaluate the effects of calcium on paste or gelatinization properties by amylograph and mixing properties by farinograph of wheat flour and on viscosity property cooking quality textural and sensory properties of Ramyon were examined. The contents of calcium used were from 1.0% to 3.0% based on flour weight. The viscosity property of wheat flour with calcium was increased the initial past-ing temperature but the amylograph peak viscosity were decreased in vice versa. The farinograph absorp-tion stability and breakdown were increased by calcium. The shear extrusion force and hardness of Ram-yon manufactured with calcium were shown much higher value than those of control. At cooking quality examination of Ramyon manufactured with calcium weight of cooked Ramyon was increased by volume was decreased. Extraction amounts of Ramyon manufactured with calcium during cooking were much smaller than those of control. These changes will provided many advantages in the preparation of Ram-yon. The I2 reaction value of Ramyon manufactured with calcium and control were shown to almost same values. Sensory properties of cooked Ramyon which was manufactured with calcium showed quite acceptable. Based on the cooking and sensory evaluation test addition of 0.3% calcim to wheat flour may be suitable for processing Ramyon.

• Journal of the Korean Society of Visualization
• /
• v.15 no.3
• /
• pp.14-19
• /
• 2017

Increase of blood viscosity significantly changes the flow resistance and wall shear stress which are related with cardiovascular diseases. For measurement of blood viscosity, microfluidic method has proposed by monitoring pressure between sample and reference flows in the downstream of a microchannel with two inlets. However, it is difficult to apply this method to unknown flow conditions. To measure blood viscosity under unknown flow conditions, a microfluidic method based on micro particle image velocimetry(PIV) is proposed in this study. Flow rate in the microchannel was estimated by assuming velocity profiles represent mean value along channel depth. To demonstrate the measurement accuracy of flow rate, the flow rates measured at the upstream and downstream of a T-shaped microchannel were compared with injection flow rate. The present results indicate that blood viscosity could be reasonably estimated according to shear rate by measuring the interfacial width and flow rate of blood flow. This method would be useful for understanding the effects of hemorheological features on the cardiovascular diseases.

• Food Science of Animal Resources
• /
• v.18 no.3
• /
• pp.209-215
• /
• 1998

Effects of protein concentration, ionic strength, pH, and temperature range on the heat-induced denaturation of salt soluble protein extracted from spent layer meat were investigated. Viscosity of salt soluble protein heated at 65$^{\circ}C$ for 30 min began to increase sharply above 7 mg/ml of breast protein concentration, and above 21 mg/ml of leg protein concentration, respectively. Both turbidity and viscosity showed the highest value in cooked protein solution with pH 6.0 and 1% NaCl. The turbidity of salt soluble protein started to increase continuously from 40$^{\circ}C$ to 80$^{\circ}C$. The viscosity increased rapidly from 45$^{\circ}C$ to 60$^{\circ}C$ in breast protein, and increased from 50$^{\circ}C$ to 55$^{\circ}C$ in leg protein, respectively, and then kept relatively constant. Breast protein had higher viscosity than leg protein during heat-induced gelation. Therefore, salt soluble protein from spent layer meat was associated with denatured protein (turbidity change) prior to gelation (viscosity change) during heating. Breast protein showed lower thermal transition temperature, and better gel formation than leg protein during heating.

• Journal of ILASS-Korea
• /
• v.27 no.2
• /
• pp.77-83
• /
• 2022

In this study, the thickness of the liquid sheet formed by a low speed impinging jet onto a flat plate was measured by the direct contact method. The spatial distribution characteristics of the sheet thickness in the radial and circumferential directions, and the effects of jet velocity and liquid viscosity were analyzed. The measurement results were compared with the theoretical predictions. The wavy surface was observed in the case of low viscosity water, but not in the high viscosity aqueous glycerol solutions. The sheet thickness increased as the circumferential angle increased or the distance from the impinging point increased, but the thickness decreased as the circumferential angle increased around the impinging point. As the jet speed increased, the sheet thickness decreased, and the sheet thickness increased as the liquid viscosity increased. Comparison with the theoretical predictions showed that the measurement results agreed well in the case of low viscosity water or high viscosity liquids around the impinging point. The distribution characteristics of the sheet thickness can provide useful means for prediction of spray characteristics in splash plate injectors.

• Journal of the Korea Convergence Society
• /
• v.10 no.2
• /
• pp.41-48
• /
• 2019

The effects of HPMC (hydroxypropyl methylcellulose) on instant fried noodles regarding oil uptake and in vitro lipid digestibility were evaluated according to different viscosity levels, as well as the same apparent viscosity. The oil uptake and lipid digestibility decreased with the increasing HPMC viscosity and replacement level, demonstrating that the reduced oil uptake and lipid digestibility may be caused by the high viscosity of HPMC. Furthermore, the oil uptake and lipid digestibility of noodles with HPMC at both apparent viscosities decreased with the increasing viscosity of HPMC in spite of having the same apparent viscosity. As a result, the high viscosity of HPMC on instant fried noodles was more critical factor compared to apparent viscosity for lowering oil uptake and lipid digestibility.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.329-329
• /
• 2017

The study was conducted to investigate the effects of different harvesting time on pasting properties of starch in three colored rices. Seven major parameters of starch pasting properties, peak viscosity (PKV), hot pasting viscosity (HPV), cool pasting viscosity (CPV), setback (CPV minus PKV), breakdown (PKV minus HPV), peak time, and pasting time were determined by Rapid Visco Analyzer. The peak viscosity, hot viscosity, cool viscosity and peak time were influenced by different harvesting times. Pasting time was delayed slightly with prolonged harvesting time in all rice cultivars. Pasting temperature in each rice cultivar differed from each harvesting time, and pasting temperature of the two rice cultivars, Hongjinju and Joseongheugchal, showed the highest at the 40 days after heading and then it decreased at the final harvesting time. With the delay of the harvesting time, peak viscosity, hot viscosity, cool viscosity, setback value and pasting temperature did not exhibit a regular trend depending on their genetic characteristics. Branch chain length distribution of amylopectin was demonstrated a distinct difference among these colored rices. In changes of amylopectin branch chain-length distribution, the amylopectin structure of Hongjinju rice cultivar as affected by different harvesting time, the shortest chain length of amylopectin in rice starch harvested at 20 days after heading was characterized by the significant increase in A chains with $DP{\geq}12$ and remarked decrease in long chains $37{\leq}DP$ compared to that of 30, 40, and 50 days after heading. In particular, when harvesting time is delayed the distribution percentage of short chain (A chains with $DP{\geq}12$) was increased except for the rice which harvested 20 days after heading. The similar results were also observed in Sintoheugmi rice cultivar like that of Hongjinju rice cultivar. Otherwise, distribution percentage of the shortest chain length of amylopectin in rice starch harvested at 20 days after heading was characterized by the significant decrease in A chains with $DP{\geq}12$ and remarked increase in B chains $13{\leq}DP{\geq}24$ compared to that of 30, 40, and 50 days after heading.

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

• The KSFM Journal of Fluid Machinery
• /
• v.19 no.1
• /
• pp.31-36
• /
• 2016

Hydraulic actuator is a primary component of the hydraulic valve systems. In this study, the thrust performance of hydraulic actuator was studied with different values of viscosity of hydraulic oil and rod diameter. Numerical analysis was performed using the commercial CFD code, ANSYS with 2-way FSI(Fluid-Structure Interaction) method and $k-{\varepsilon}$ turbulent model. Results show that increase in viscosity of hydraulic oil reduces the thrust of hydraulic actuator. In order to satisfy the output required of the actuator, it is necessary to compensate for the operating pressure. The results of pressure, velocity and thrust efficiency distributions in the hydraulic actuator were graphically depicted.

• Proceedings of the KSME Conference
• /
• 2001.06e
• /
• pp.738-741
• /
• 2001

The purpose of the present study is to measure the viscosity of liquid in the capillary tube viscometer using the unsteady flow concept. The capillary tube viscometer is consisted of a small cylindrical reservoir, capillary tubes, and the mass flow rate measuring system interfaced with computer. Two capillary tubes with 1.152 and 3.002 mm I.D. are used to determine the diameter effects on the viscosity measurements. The instantaneous shear rate and gravitational driving force in the capillary tube are determined by measuring the mass flow rate through the capillary tube instantaneously. The measured viscosities of water and aqueous Separan solution are in good agreement with the reported experimental data.