• Journal of the Korean Graphic Arts Communication Society
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• v.22 no.2
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• pp.23-36
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• 2004

The surface tension method has been possible only for the low viscosity materials. However, the inks for the off-set lithography and intaglio should have high viscosity and high tack. In this paper, we propose the elongation method to estimate the surface tension of high viscosity printing inks. The elongation method could be more useful to estimate the surface tension and shown in this research, it is possible to calculate the surface tension of high viscoxity ink without diluting the sample.

• Proceedings of the KWS Conference
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• 2000.10a
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• pp.256-259
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• 2000

High viscosity mixing powder is a very useful material for laser cladding. This material has a high viscosity so that it can be sticked to substrate. Therefore, Laser cladding can be performed on a curved or slope surface. Laser cladding can be easily performed with the material instead of wire that is difficult to be manufactured in some case. In this experiment, it was used a high viscosity mixing powder which consists of a high temperature flux and a bronze powder. And AC2B alloy material was used as a substrate. Flux prevents the clad layer from being oxidized and increases bonding property between substrate and cladding material. It makes possible to laser cladding at low level energy.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.5
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• pp.1-10
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• 1994

By applying of total electric capacitance method on engine connecting rod bearing during engine operating, the influence of engine operating conditions and lubricants on bearing oil film thickness was investigated. Minimum oil film thickness increases with kinematic viscosity, but as increasing of viscosity, the increasing ratio of film thickness is reduced. Also minimum oil film thickness increases with engine speed but there is a limit. Above this limit, film thickness decreases in opposition because of crankshaft inertia. As increasing of engine torque and oil temperature, munimum oil film thickness decreases linearly. For non-Newtonian oils, the correlation between $100{\circ}C$ kinematic viscosity and munimum oil film thickness is very poor.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.243-248
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• 2004

Brake theory of viscosity, which can sucessfully calculate the viscosity of real gases, dense gases and liquids, is extended to the binary gas mixture. Adjustable parameters are not involved, but the calculated results are good agreements with the experimental values at high pressure as well as low pressure. Corresponding state equation for viscosity can be obtained by using the Redlich-Kwong equation, so that we hope this equation may be useful for the supercritical fluid in engineering applications at high pressure around the critcal point.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.4
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• pp.258-265
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• 2016

Digital printing has been used in various industrial areas, including semiconductor manufacturing and textile printing. However, implications on ceramic textile have not been well established so far. Printing high-viscosity materials requires an understanding of their behavior. An inorganic high viscous material with a viscosity range of 20-30 cps is analyzed using a viscometer and through X-ray diffraction. In this study, a digital printer is designed and assembled using a high-viscosity material with software for PC control, resulting in reduced processing at a fast area velocity of $20m^2/hr$. The present study demonstrated that the printer is capable of controlling the shape of the drop mass to smear ink smoothly onto the ceramic surface under an economic budget. In addition, to avoid any difficulty in color management, the ceramic printer is equipped with an independent color management system designed to cope with images on a highly viscous material.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.121-127
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• 2011

This study used two types of rheology modifiers including an alkali-swellable emulsion (ASE) and an surface-adhesion emulsion (SAE) to elucidate their effects on high shear viscosity and dynamic penetration behavior among the flow properties of high solids coating. Since rheology under high shear and dynamic penetration behavior significantly affect the quality of coated paper in case of high solids coating, it is very important to examine the variations in rheology of high solids coating color by rheology modifier. It was found that the high solids coating color prepared with the SAE type showed superior dynamic penetration behavior and high shear viscosity than that with the ASE type rheology modifier.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.367-370
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• 2003

In this study the effects of fluid viscosity on the pump performances of a conventional centrifugal pump were experimentally studied. The study aimed to compare the pump characteristics for water and high viscosity fluids. The Working fluids are water, aqueous sugar solution and glycerin solution. The pump characteristics of total head and efficiency with high viscosity fluids were different. The performance curves of efficiency for the sugar and glycerin solutions were decreased up to 8.1% and 12.9% than that of water.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.2
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• pp.124-131
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• 2016

Several research works for finding and optimizing the methods of dispensing high viscosity phosphor used in the fabrication of white LED's are currently in progress. High viscosity phosphor dispensing with a high accuracy is crucial because the dispensing rate and uniformity directly affect parameters such as the CIE chromaticity diagram, color temperature and luminous flux of white LED's. This study presents a novel method of dispensing high viscosity phosphor using electrohydrodynamic printing. The dispensing rate was optimized less than 0.01 mg phosphor using experiments and optimizing the process parameters including the standoff distance from the nozzle to the substrate, ink supply pressure, and multi-step pulsed waveform magnitude ratio. The dispensing rate was measured by dispensing 20 dots using drop-on-demand with the optimized parameters, and the experiments were repeated 10 times to maximize the data accuracy. The average dispensing rate that can be reliably used for high viscosity phosphor dispensing was 0.0052 mg.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1505-1509
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• 2004

The suspension of hardened red blood cells (RBCs) differs from the suspension of normal RBCs with respect to their rheological behavior. The deformability of normal and hardened RBCs (obtained by heating blood at $49^{\circ}C$ or by incubating RBCs in a solution of hydrogen peroxide) was measured with a slit diffractometer and RBC suspension viscosity was measured with a rotational viscometer. The peroxide-treated RBCs showed a significant decrease of the deformability and their suspension viscosity increased over a range of shear rates. The suspension viscosity of the heated RBCs, however, where the deformability is even lower than that of the peroxide-treated RBCs, was slightly higher than that of the normal RBC suspension in the high shear rates. The present study found that not all rigid cells cause an increase of blood viscosity at high shear rate, and therefore that decreased membrane deformability is not predictive of high-shear blood viscosity.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1151-1157
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• 1997

The chemical identities of purified polysaccharide, methylan, were analyzed by various chemical methods. The polysaccharide contained 79%(w/w) sugar, 6% protein, and 16% organic acids such as uronic acid, pyruvic acid, and acetic acid. With proceeding fermentation, the acids content in methylan increased from 10% at 34 hr to 17% at 72 hr, and the viscosity of methylan in the same concentration also increased. The correlation between viscosity and acid content in methylan was studied using chemically or biologically modified methylan. Methylan with a high content of pyruvic acid exhibited a high apparent and an intrinsic ·viscosity. When the pyruvic acid content of methylan with the same content of uronic acid was increased 1%, apparent viscosity and intrinsic viscosity increased 290 cp and 6 dL/g, respectively. Methylan with a high content of uronic acid exhibited a high apparent and an intrinsic viscosity. When the uronic acid content of methylan with the same content of pyruvic acid was increased 1%, apparent viscosity and intrinsic viscosity increased 85 cp and 1.5 dL/g, respectively. It was found that the increased viscosity of methylan resulted from the increased content of organic acids in methylan, and pyruvic acid was more an important factor contributed to the increase of methylan viscosity than uronic acid.