• 제목/요약/키워드: the viscosity

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Detection of Irradiated Korean Wheat Flour by Viscosity and Pulsed Photostimulated Luminescence (PPSL) Methods

  • Yi, Sang-Duk;Chang, Kyu-Seob;Oh, Man-Jin
    • Preventive Nutrition and Food Science
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    • v.10 no.2
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    • pp.140-144
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    • 2005
  • This study was carried out to establish methods for irradiation detection of irradiation in Korean wheat flour by pulsed photostimulated luminescence (PPSL) and viscometric methods. The photon counts of the irradiated Korean wheat flour measured by PPSL immediately after irradiation increased with increasing irradiation dose. The photon counts in the irradiated Korean wheat flour almost disappeared with lapse of time after storage in normal room conditions, but irradiation detection was still possible after 6 months in darkroom conditions. All irradiated samples indicated a decrease in viscosity with increasing stirring speeds (rpm) and irradiation doses. Irradiation at 1 kGy significantly decreased the viscosity. Consequently, these results suggest that the detection of irradiated Korean wheat powder is possible by both viscometric and PPSL methods.

Effects of Polysaccharide Hydrolase on Solids Yields and Viscosity of Aqueous Extracts of Sea Mustard (다당류 분해효소의 첨가가 미역 추출액의 수율 및 점도에 미치는 영향)

  • Choi, Hee-Sook;Kim, Woo-Jung
    • Korean Journal of Food Science and Technology
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    • v.25 no.5
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    • pp.589-591
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    • 1993
  • Effects of enzymatic hydrolysis of polysaccharides with using three commercial mixed enzymes (Ultrazyme, Celluclast, Viscozyme) were investigated on supernatant ratio, solid yields and viscosity of sea mustard extracts. The result showed that enzymatic hydrolysis prior to extraction increased the solids concentration up to 27.3% and the solids yield up to 14.0%. However the supernatant ratio after centrifugation of the sea mustard suspension was rather reduced. The viscosity of the extracts was significantly increased during initial enzymatic hydrolysis.

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Preliminary Study on the Relationship between Viscosity of Paste and Flowability of Mortar (페이스트 점도에 의한 모르타르 유동 특성에 관한 기초 연구)

  • Kim, Seung Hyun;Park, Chung-Hoon;Kim, Baek-Joong;Yi, Chong-Ku;Kang, Kyung-In
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.11a
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    • pp.269-270
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    • 2012
  • In this study, for purpose of having a prediction on the flowability of mortar, we use the theory of excess paste, which gives a relationship between viscosity of paste versus water-binder ratio and mortar flow versus relative excess paste volume. Pastes and Mortars with four different mix proportions incorporating mineral admixtures were prepared. As a result of experiment, it seems that high flowability of mortar can be attributed to both lower viscosity of paste and increasing the volume of excess paste.

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The Effect of Biodiesel and Ultra Low Sulfur Diesel Fuels on Emissions in 11,000 cc Heavy-Duty Diesel Engine

  • Baik, Doo-Sung;Han, Young-Chool
    • Journal of Mechanical Science and Technology
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    • v.19 no.3
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    • pp.870-876
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    • 2005
  • It seems very difficult to comply with upcoming stringent emission standards in vehicles. To develop low emission engines, better quality of automotive fuels must be achieved. Since sulfur contents in diesel fuels are transformed to sulfate-laden particulate matters as a catalyst is applied, it is necessary to provide low sulfur fuels before any Pt-based oxidation catalysts are applied. In general, flash point, distillation $90\%$ and cetane index are improved but viscosity can be worse in the process of desulfurization of diesel fuel. Excessive reduction of sulfur may cause to degrade viscosity of fuels and engine performance in fuel injection systems. This research focused on the performance of an 11,000 cc diesel engine and emission characteristics by the introduction of ULSD, bio-diesel and a diesel oxidation catalyst, where the bio-diesel was used to improve viscosity of fuels in fuel injection systems as fuel additives or alternative fuels.

Comparison of shear rate and viscosity of the commercial dental impression materials (치과진료용 인상재의 전단율과 점도의 비교)

  • Jin, Myoung-Hoon;Lee, Kwang-Rae
    • Journal of Industrial Technology
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    • v.34
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    • pp.11-14
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    • 2014
  • Viscosity and shear stress of the dental impression materials on commercial market(Imprint Garant LB(3M, U.S.A), EXAMIXFINE IT(GC, Japan), Vonflex S LB(Vericom, Korea), S-Silicone LB(Shinwon, Korea)) were measured with increasing shear rate from 50(1/sec) to 100(1/sec). The viscosity of EXAMIXFINE IT was decreased from 20,542(cP) to 14,684(cP), which is the shear thinning property of pseudoplastic as non-Newtonian fluid. Since the pseudoplastic property makes the impression material shear thinning and softly injected from cartridge, EXAMIXFINE IT might be popularly used in dentistry.

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A Study of Rheology Properties of AM50A Magnesium Alloy (AM50A 마그네슘합금의 레오로지 특성에 관한 연구)

  • Han S.H.;Lee J.H.;Kang C.G.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.431-432
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    • 2006
  • In this study, the effect of the temperature of magnesium slurry was investigated by mechanical stirring method. The evaluations of rheological behavior of AM50A magnesium alloy were measuring of viscosity and microstructures in the semisolid state. The apparent viscosity was investigated at continuous cooling rate using a concentric cylinder viscometer. Measurement of viscosity measures torque that act to stirrer rotating in slurry doing continuous cooling using torque-meter and expressed by POWER-LAW. Microstructures were observed after mechanical stirring that enforce time at steady state temperature of solid fraction.

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Risk Evaluation of Biodiesel (바이오디젤연료 위험성평가)

  • Kwon, Kyung-Ok
    • Fire Science and Engineering
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    • v.22 no.5
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    • pp.79-82
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    • 2008
  • Biodiesel is manufactured from vegetable oils, etc. in reaction with methanol so that the product of biodiesel may be dangerous due to the methanol remained of it. The risks of methanol remained in biodiesel were studied by measuring flash points and dynamic viscosity to some samples of biodiesel by adding methanol to a certain percentage of. The results of flash points of biodiesel are decreased in accordance with increasing of methanol in biodiesel and also decreasing the dynamic viscosity. It was shown that the risks of explosion of biodiesel are significantly high due to lower flash points resulted from methanol remained in biodiesel fuel as a reactant or adding to biodiesel for reduction of viscosity.

Method for Rapid and Accurate Measurement of Chitosan Viscosity

  • No, Hong -Kyoon;Samuel P. Meyers
    • Preventive Nutrition and Food Science
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    • v.4 no.2
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    • pp.85-87
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    • 1999
  • A simple and rapid method to estimate the viscosity of chitosan using laboratory pipettes was developed. The voscosities of nine different chitosan samples, prepared ini 1 % acetic acid at a 1% concentration , were measured with a standard viscometer. Prior to measurement of flow time of 1% chitosan solution with a pipette, twelve pipettes were assorted into three groups with flow times of 4, 5 and 6 sec after measuring passage of 9 ml of 1% acetic acid througth a 10 ml pipette. With each group of pipettes. flow time of 1% chitosan solution was determined by measuring the delivery time of 5 ml of the 10ml solution through a 10 ml pipette. Results of regression analyses revealed high linear relationship(R2=0.9812, 0.9663, and 0.9754) between viscosities calculated with a viscometer and flow times measured with 4, 5 or 6 sec group pipettes. The viscosity of chitosan could be readily and accurately estimated from these linear regression equation by measuring flow times based on pipette delivery.

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Property and Polymerization of Hi-solid PSA's using Seeded Polymerization (Seed 중합을 이용한 고고형분 수용성 점착제의 합성과 물성)

  • Jung, Young Sik;Min, Seong-Kee;Seul, Soo Duk
    • Journal of Adhesion and Interface
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    • v.10 no.4
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    • pp.174-181
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    • 2009
  • The viscosity for hi-solid pressure sensitive adhesive to improve water soluble low viscosity pressure sensitive adhesive polymerized using seeded polymerization. While seed binder polymerizing it produces an optimum polymerization condition, and acrylic acid and seed binder concentration changed were measurement of viscosity variation and adhesive power at the substrate (SUS420J) as flowing results. In adhesive polymerization, seed binder concentration 7 wt%/monomer was recovered 60% of solid content, 2,100 cps of low viscosity and clear adhesive film. When acrylic acid content was 4 wt%/monomer, it was turned excellent adhesive power and holding power.

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STRONG CONVERGENCE OF NEW VISCOSITY RULES OF NONEXPANSIVE MAPPINGS

  • AHMAD, MUHAMMAD SAEED;NAZEER, WAQAS;MUNIR, MOBEEN;NAQVI, SAYED FAKHAR ABBAS;KANG, SHIN MIN
    • Journal of applied mathematics & informatics
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    • v.35 no.5_6
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    • pp.423-438
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    • 2017
  • The aim of this paper is to present two new viscosity rules for nonexpansive mappings in Hilbert spaces. Under some assumptions, the strong convergence theorems of the purposed new viscosity rules are proved. Some applications are also included.