• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.267-271
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• 1998

In order to investigate the physical properties of alginate extracted from sea tangle, Laminaria app., under various conditions, viscosity and binding capacity of metal ion (BCMI) of alginate were measured. The higher concentrations of sodium carbonate and the longer extracting time became, the lower apparent viscosity and BCMI were. BCMI in alginate reached maximum at the concentration of 0.06M metal ion. The BCMI of $Pb^{++}$ ion was the highest but $Cu^{++}$ ion was the lowest in the five metal ions. BCMI was increased in proportion as increase of viscosity in alginate.

• Polymer(Korea)
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• v.31 no.6
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• pp.491-496
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• 2007

In the polymeric dental restorative composites, the resin matrix mainly contains 70 wt% 2,2-bis[4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA), as a base resin and 30 wt% triethylene glycol dimethacrylate (TEGDMA) as a diluent. Even though the viscosity of the resin matrix is rapidly decreased by adding TEGDMA, addition of TEGDMA to the Bis-GMA results in reduction in the mechanical properties and increase in the curing shrinkage of the dental composite. In order to fabricate dental composite exhibiting excellent properties by reducing TEGDMA content in the resin matrix, in this study, Bis-GMA derivatives, which do not contain hydroxyl groups, were used instead of Bis-GMA. The curing characteristics of Bis-GMA derivatives were similar with those of Bis-GMA, while the former exhibited lower viscosity and water absorption than the latter. Comparing the curing shrinkage of the dental composite containing Bis-GMA derivative with that prepared from Bis-GMA, the reduction in curing shrinkage was about 25%. Dental composites prepared from new resin matrices also exhibited low water uptake and better properties in mechanical strength.

• Korean journal of food and cookery science
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• v.20 no.4
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• pp.396-402
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• 2004

The aim of this study was to examine the effect of rice protein on the network structure of the Jeung-Pyun. The major component of Jeung-Pyun rice protein was extracted, the change of rice protein during the Jeung-Pyun fermentation was assessed, and the effect on the viscosity and volume of adding protease to Jeung-Pyun was investigated. In addition, the result of adding protein to rice starch on the viscosity and volume of Jeung-Pyun was that the rice protein mediated the volume and expansion ability. The results were as follows. In rice and dough of Jeung-Pyun, the SDS soluble protein content was higher than that of wheat flour and no change was detected in the amount of extracted protein with the fermentation time. However, in the FPLC pattern, low molecular weight peaks were decreased with the fermentation time, which indicates the increase in the ratio of high molecular weight substances. In contrast, the addition of protease substantially decreased, the viscosity and volume of Jeung-Pyun, whereas the viscosity and volume were increased by adding protein to rice starch in order to reconstitute Jeung-Pyun. This suggested that rice protein in Jeung-Pyun had a mediating effect on both the volume and the formation of the texture.

• Journal of the Korea Institute of Building Construction
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• v.4 no.2
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• pp.129-136
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• 2004

High fluidity concrete(HFC) requires high dosage of superplasticizer to acquire sufficient fluidity, and high contents of fine powder and viscosity enhancing admixtures to resist segregation. The use of high amount of admixtures to make HFC at batcher plant in ready mixed concrete company is one of the reasons to raise the manufacturing cost of HFC. For this reason, new type of manufacturing method of HFC are described using both flowing concrete method and segregation reducing superplasticizer(SRS) in order to gain economical profit and offer the convenience for quality control.. As dosage of melamine based superplasticizer increases, it shows that fluidity and bleeding increase, while air contents and ratio of segregation resistance decrease. It also shows that addition of viscosity agent into superplasticizer reduce bleeding and improve segregation resistance of concrete. Dosage of AE agent into superplasticizer containing viscosity agent recovers loss of air contents during flowing procedure. Combination of proper contents of superplasticizer, viscosity agent and AE agent make possible to develope segregation reducing type superplasticizer. Compressive strength of high fluidity concrete applying flowing method with it is higher than that of base concrete. No differences of compressive strength between compacting methods are found. For the estimation of construction cost of high fluidity concreting using segregation reducing type superplasicizer, under same strength levels, although material cost of high fluidity concrete is somewhat higher than that of plain concrete due to segregation reducing type superplasticizer cost, labor cost and equipment cost of high fluidity concrete is cheaper than that of plain concrete. However, based on the strength differences, high fluidity concrete shows lower material cost, labor cost and equipment cost than that of plain concrete due to decreasing in size of member and re-bar caused by high strength development of concrete.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.483-487
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• 1988

The viscosity of salt solution and Kimchi juice and salt penetration and hardness of Chinese cabbage were investigated during brining and fermentation at $4-35^{\circ}C$. The rate of salt penetration during brining increased as the temperature and salt concentration increased from 5% to 15% while the effect of temperature on the salt penetration rates(%/hr) was rather reduced as salt concentration increased. The hardness of the cabbage measured by puncture test showed a rapid initial decrease during salting and the viscosity of brine changed little. Fermentation of Kimchi resulted a little increase in viscosity of Kimchi juice while the hardness of the cabbage decreased rapidly as pH reduced to pH 4.2-4.3 and then increased a little thereafter.

• Applied Biological Chemistry
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• v.35 no.2
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• pp.69-75
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• 1992

Viscosity changes of acidified milk at the various pH $ranges(5.2{\sim}4.2)$was measured as a function of temperature. The rate and extent of acid-induced coagulation of milk protein were monitored by turbidity changes as a function of temperature, preheating and salt. Relative viscosities of acidified milk were also measured. The coagulation of casein occurred in a specific pH range and was accompanied by a sharp increase in viscosity at pH of $5.0{\sim}5.2$, depending on the heating temperatures. Onset pH of coagulation and maximum coagulation rate were enhanced by increasing temperatures and preheating process and reduced by addition of salt. Relative viscosity of acidified milk was reversed at the same conditions, reflecting the size of casein coagulum formed was related to the coagulation rate.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.533-538
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• 1990

In polysaccharide fermentation with Aureobasidium pullulans, the aeration effects on the production of polysaccharide and the rheological properties of fermentation broth were studied. The increase of the aeration rates from 0.5 to 2.0vvm at 500 rpm yielded the maximum specific production rate of polysaccharide from 0.046 to $0.093 (hr^{-1})$, and the maximum specific growth rate of cells from 0.168 to $0.192 (hr^{-1})$. The viscosity behavior of fermentation broths at the different aeration rates followed the power-law ${\tau}= K({\gamma})^n$. The viscosity attributed by cells was about 10% of the total viscosity of fermentation broth and most of viscosity was attributed by the polysaccharide produced. The relationship between power-law parameters and the concentration of polysaccharide generally satisfied the etㄴrations with the regression coefficient greater than 0.980, $lnK(t)= ln({\tau})_o-n(t)\;ln({\gamma})_o\;and\;K(t)=A P(t)^B$.

• Clean Technology
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• v.20 no.2
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• pp.97-102
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• 2014

Currently various studies are underway for dispensing high-viscosity phosphor. These studies have reported limitations and challenges in the dispensing process. The discharged amount of phosphor was approximately the same each time which is important for the implementation of high-efficiency white LED technology. This paper present high-viscosity phosphor dispensing process for white LED implementation by using electrostatic printing technology. The voltage controlled DOD (Drop-On-Demand) discharge experiment was studied to determine angle of drop meniscus at nozzle and dot diameter. With increase in Discharge voltage, the discharge angle of meniscus increased while dot diameter decreased. Therefore it can be concluded that we can control the discharge rate by controling the discharge angle of meniscus.

• Elastomers and Composites
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• v.1 no.1
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• pp.49-55
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• 1966

Based upon the results of the previous work, the experiments are concentrated on the improvement of the durability of rubber coated fabrics as a rain garment material. To obtain a much lighter and durable coated fabric, several kinds of light weight cotton prints having almost equal density in warp and fillingwise were chosen. Rubber coating on these prints was made by topping and spreading process using rubber compound of various viscosity, and the physical properties of final product were analysed and interpreted in terms of adhesion and durability. The results are as follows. 1. Any noticeable difference between two coating processes was not found in terms of physical properties. 2. Base fabrics should be dipped once into a dilute rubber compound before coating operation in order to obtain a uniform adhesion and physical properties, and the optimum range of the viscosity of dipping paste are from 100 poise to 200 poise. 3. Generally, the tearing strength of the coated fabrics is inversely proportional to the adhesion. 4. It was assumed that the increase of the water proofness after water immersion on the finished material which have dense base fabric is chiefly due to the swelling of the cellulosic fiber.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.397-404
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• 2016

The objective of this study is to determine the physical characteristics of the gel mass of vegetable soft capsules and to maintain their rheological stability for improving manufacturability. The effect of each capsule shell component on the viscosity of the gel mass was studied for 6 hours, and the effects of adding an alkalizer or electrolytes to neutralize the sulfate groups on the carrageenan molecule were also investigated. Carrageenan was identified as a major component that affects the viscosity of the gel mass, and it showed unstable properties with age. The viscosity and stability of the gel mass were remarkably improved when an alkalizer or electrolytes were added at 3.0% relative to the carrageenan. 3.6 M KCl showed the highest effect on increasing the viscosity. A stable gel mass composition for vegetable soft capsules was successfully developed, which can be considered to increase the application of the capsules in the pharmaceutical and food industries.