• 대한화학회지
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• 제16권1호
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• pp.25-32
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• 1972

The effect on the apparent viscosity of 2 wt. % Veegum suspensions of different types of electrolytes and of different electrolyte concentrations was studied. Measurements were made with a Brookfield Synchro-Lectric Viscometer, using no.3 spindle at 30 R.P.M. at $24^{\circ}C$. As electriolyte concentration increased, the apparant viscosity was observed to increase to a maximum and then to decrease. Changes in viscosity were in general agreement with predicted results based on the Hofmeister sequence and the Schulze-Hardy rule. The observed electrolyte effect on the apparent viscosity was discussed in terms of the Verwey-Overbeek theory.

• 유변학
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• 제5권2호
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• pp.161-169
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• 1993

Glucomannan(G.M.)은 Amorphophallus Konjac C. Koch의 tuber로부터 분리되었고. 이 G.M.은 다시 침전제로 메탄올을 사용하여 4단계로 분별되었다.(F.1, F.2, F.3, F.4,). 각분 별물에 비하여 직선으로부터 벗어남을 보였다. Low shear viscometer로 G.M. 용액의 viscosity를 측정하였고 농도와 zero shear specific viscosity의 logarithm을 도시한 결과 inflection point를 나타내었다. 이것은 G.M. 분자들의 coil overlap의 시작에서 기인한 것이 고 묽은 용액에서 진한 용액으로의 전이행동은 임계농도. C＊=4/[η]에서 일어났고 이때의 zero shear specific viscosity는 10을 나타내었다. 또한 specific viscosity는 묽은 용액에대해 서는 C14로써 변화하였고 진한 요액에서는 C3.0으로변화하였다. G.M.의 고체상태에 대한 유 전성($\varepsilon$＇,$\varepsilon$＂)과 점탄성(C＇,C＂)계수들을 액체질소 온도에서부터 15$0^{\circ}C$ 온도범위에 걸쳐 4단계로 film을 건조시키면서 10Hz에서 측정하였다. G.M. film의 유전성과 점탄성의 허수부 분은 ($\varepsilon$＂, C＂), -10$0^{\circ}C$에서 peak를 나타내었고 이 peak는 hydroxy methyl 기들의 회전 운동에서 생겨난 것이다. 건조시키지 않은 상태의 G.M. film의 유전성과 점탄성의 허수부분 의 값들은 -5$0^{\circ}C$에서 물 분자의 운동에 의하여 생긴 peak를 보였다.

• 한국식품영양학회지
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• 제13권1호
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• pp.78-82
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• 2000

For the purpose of investigation of the food processing fittness of the sea mustard aqueous extracts, the steady shear flow have been measured over a wide range of shear rate using a Brookfield digital viscometer(SPDL21). The rheological behaviors of the sea mustard aqueous extracts which were extracted at 10$0^{\circ}C$ for 2 hours exhibited pseudoplastic behavior with yield stress. In the test of the relationship between temperature and apparent viscosity of samples at 10 rpm decreased along with the increment of temperature. The sea mustard aqueous extracts appeared greatly temperature dependent characteristics(Ea=1.51 ㎉/mole).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.675-678
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• 2005

Cement paste is originally the basic material and crucial factor consisting concrete. This study investigates the relationship between flow apparatuses, which are ring flow, flow cone and mini slump, in order to estimate the fluidity of cement paste. For quantitatively evaluating the measured data, this study also analyses the calibration of the rheology consistents of cement paste using viscometer. For this purpose, the present work discusses the influence of the differences of companies and ingredients, affecting the fluidity of cement paste

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.49-52
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• 2004

New hydrophobic alumina nanoparticles were synthesized from alumina powders which were hydrophilic nano-agglomerates with diameters from ${\mu}m$ to mm by surface modification. The synthesized hydrophobic alumina nanoparticles which were retreated with Oleic acid were analyzed by Fourier transform infrared spectrophotometer and transmission electron microscopy. Then transformer oil containing surface-modified alumina naonparticles were synthesized. The synthesized hydrophobic alumina nanoparticles were well-dispersed in transformer oil. The coefficient of viscosity and dielectric strength of the Nano-transformer oil were investigated with viscometer and high voltage experiment device. In this study, the thermal conductivity of Nano-transformer oil was investigated to reduce the oil temperature of transformer by transient hot-wire method.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.61-64
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• 2000

In order to analyse the effect of the fluid viscosity changes on the centrifugal pump, the computer simulation method and the performance correction chart are used. The centrifugal pump is designed using the traditional method, and the 3D computational grid is generated for the impeller and casing. Working fluids are water, high viscous oil and muddy water. The viscosity of muddy water is measured by the unsteady capillary tube viscometer. The pump performances are predicted well through the computer simulation. The performance curves of head and efficiency for oil and muddy water are decreased. The torques of oil and muddy water, which is calculated by performance correction chart are predicted at a lower value than the computer simulation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.97.3-97
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• 2001

An experimental study was performed to establish the validity of an on-line state estimator for a semibatch MMA-MA copolymerization reactor by using on-line densitometer and viscometer under two different operating conditions; one without additional solvent feed and the other with solvent fed additionally. A conventional extended Kalman filter (EKF) was used as the state estimator and the experiment was conducted for the purpose of application to the control of copolymer properties. Further analysis was made by using off-line measurement data for the mole fraction of MMA in the remaining monomers and the solid content. It was found that the EKF could provide a good estimate for the states of the copolymerzation system ...

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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• pp.165-170
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• 2001

This paper presents performance analysis of two-linked robot system using ER (electro rheological) valve actuators. An ER fluid consisting of soluble chemical starches (particles) and silicone oil is made and its field-dependent yield stress is experimentally distilled using electro-viscometer. From this result, the design parameters of ER valve are determined. Based on parameter study, an ER valve system is designed and manufactured. Furthermore, the measured pressure drop is compared with predicted one obtained from the Bingham model. Following the evaluation of field-dependent pressure drop of ER valve, a two-linked robot system with two ER valve actuators is then constructed and its governing equation of motion is derived. From this equation, PID controller is established. Consequently, control performances of the proposed two-linked robot system featuring ER valve are evaluated.

• 한국식품조리과학회지
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• 제19권6호
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• pp.723-728
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• 2003

The sensory characteristics of cream soup containing 0, 25, 50, 75 and 100％ rice flour were investigated in order to develop a new processed food using rice. The Hunter L(lightness) value increased with the amount of rice flour, while the a(redness) value and b(yellowness) value decreased, significantly. The viscosity of rice cream soup significantly decreased with the increasing amount of rice flour. Based on the sensory evaluation, the cream soup samples with larger rice flour component showed a higher clean taste score, while those with the least rice flour resulted in higher darkness, viscosity, greasy taste, md softness. The overall acceptance was the highest in the cream soup with 75％ and 100％ rice flour. In terms of the color and viscosity, good correlations were observed between the sensory evaluation and the objective analysis. The overall acceptance showed a significant positive correlation with a clean taste, while there was a negative correlation with a greasy taste and the viscosity measured by a viscometer.

• Structural Engineering and Mechanics
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• 제58권1호
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• pp.93-102
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• 2016

This article presents an experimental study on the effect of temperature and solid volume fraction of nanoparticles on the dynamic viscosity for the CuO/EG-water nanofluid. Nanoparticles with diameter of 40 nm are used in the present study to prepare nanofluid by two-step method. A "Brookfield viscometer" has been used to measure the dynamic viscosity of nanofluid with solid volume fraction up to 2% at the temperature range between 20 to $60^{\circ}C$. The findings have shown that dynamic viscosity of nanofluid increases with increasing particle volume fraction and decreasing temperature. Nine different correlations are developed on experimental data point to predict the relative dynamic viscosity of nanofluid at different temperatures. To make sure of accuracy of the proposed correlations, margin of deviation is presented at the end of this study. The results show excellent agreement between experimental data and those obtained through the correlations.