• The Korean Journal of Food And Nutrition
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• v.13 no.1
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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).

• Structural Engineering and Mechanics
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• v.58 no.1
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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.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1171-1178
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• 2006

This study examined the effects of flavors, which are usually added to improve the appeal of pharmaceutical agents, on the viscosity and gelling point of 18% (w/w) aqueous poloxamer 407 solutions. Monoterpenes, esters, alcohols, aldehyde ketones and lactone type flavors were examined. The concentrations of flavor ranged from 0.1 to 1.0%(w/w). After adding a flavor to the aqueous poloxamer 407 solution, the viscosity of the solution was measured using a Brookfield viscometer, and the gelling point was determined from the viscosity vs. temperature plot. The gelling point of the aqueous poloxamer 407 solution decreased with increasing concentration of flavors except for coumarin, vanillin and ethylvanillin. Thermal analysis with DSC showed an interaction between the flavors and poloxamer 407. These results suggest that the flavors bind to the hydrophilic end chains of poloxamer 407, which increases the viscosity, causing gelation at lower temperatures.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.205-205
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• 2017

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.114-121
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• 2000

A study was carried out to establish a detection method for irradiated black and white pepper. Samples were packed in polyethylene bags and irradiated with 2.5, 5, 7.5, 10 and 15 kGy using a Co-60 irradiator. The samples were suspended in water, and alkalized with sodium hydroxide solution. Apparent viscosity was determined after heat gelatinization using a Brookfield DV-III rotation viscometer at 30。C with 30, 60, 90, 120, 150, 180, and 210 rpm. Means and standard deviations of the viscosities of all samples decreased by increasing the stirring speeds. The viscosities increased in all samples by increasing the concentration. Regression expressions and coefficients of viscosity which decreased with increasing irradiation dose of 10% and 13% black pepper, and 7% and 10% white pepper were 0.9531 (y=-131.29x+1,769.0), 0.9725 (y=-351.33x+4,036.0), 0.9731 (y=2,208.0e${^-0.3546X}$), and 0.9959 (y=5,116.0e${^-0.2887X}$), respectively, at 120 rpm. This trend was similar fur all stirring speeds. These results suggest that the detection of irradiated black and white pepper at various doses is possible by the viscometric method.

• Korean Journal of Agricultural Science
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• v.18 no.1
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• pp.41-48
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• 1991

Rheological properties of gelatinized potato starch were investigated with Brookfield wide-gap viscometer at various conditions. The gelatinized potato starch at 3-7% showed a pseudoplastic behavior with yield stress, and presented thixotropic properties with time-dependent structural decays. The consistency index and yield stress of gelatinized starch were proportional to starch concentration but inversely proportional to measurement temperature, and the flow behavior index did not show constant relationship. The consistency index and yield stress of the gelatinized starch on addition of phosphate decreased as the flow behavior index increased. The values of activation energy at initial and equilibrium were 1.52 kcal/g.mole and 127 kcal/g.mole, respectively.

• Polymer(Korea)
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• v.36 no.1
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• pp.29-33
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• 2012

Solution type pressure sensitive acrylic adhesives were synthesized from 2-ethylhexyl acrylate (2-EHA) as a base monomer and acrylic acid as a functional monomer. The surface energy and basic physical properties of synthesized PSA (pressure sensitive adhesives) were investigated as a function of contents of acrylic acid and crosslinking agent. The structures of adhesive were identified by FTIR. Viscosities and molecular weights of PSA were measured by a Brookfield viscometer and GPC, respectively. Consequently, molecular weight and viscosity increased as the contents of acrylic acid increased up to 6 wt% and then decreased at higher contents. Surface energy increased as the contents of acrylic acid increased owing to the increase of COOH groups, which yielded the enhancement of polarity of PSA. On the other hands, their peel strengths were inversely proportional to molecular weight and showed tendencies of decreasing as the contents of acrylic acid and crosslinking agent increased.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.379-383
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• 1997

To study the effect of amylose on the mechanism of gel formation, swelling power, water solubility, the pattern of alkali gelatinization and gel properties were investigated. The swelling power of waxy maize starch (Amioca) was the highest and followed by those of PFP > Amaizo > Amylomaize VII. Amioca showed higher iodine affinity of soluble amylose than other maize starches. The apparent viscosity of alkali gelatinization measured by Brookfield viscometer for Amaizo was 70${\times}$10$^3$cp which was higher than Amylomaize VII. The apparent viscosity of PFP was increased to 70${\times}$10$^3$cp and then decreased. As maize starches were autoclaved at 121$^{\circ}C$ with starch: water ratio (1 : 9) and autoclaving-cooling cycle were up to 4 times, gel properties were measured by rheometer. Amaizo showed the highest value for hardness, adhesiveness, springiness, and cohesiveness, and hardness of gel after two cycles of autoclaving-cooling was the highest. Gel properties seemed to be affected by the chain length of amylose rather than the content of amylose.

• Journal of Nutrition and Health
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• v.19 no.1
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• pp.3-15
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• 1986

This study was intended to investigate the rheological properties of the development formula of infant foods and the results are summarized as follow ; 1) Consistency of starch solutions measured by Brabender Anylograph and Brookfield viscometer showed that waxy rice and riece with malt had lower consistency and more rheological stability.The flow type of tested raw materials and formula was found to ？ pseudoplastic, as judged by n-value of 0.332 -0.692, and no yield value. 2) The influenced of temperature on consistency could be accounted for by the equation, In (n) = K(1/T) + const. this relationship indicated that consistency of tested sample increased as temperature decreased. The consistency of waxy rice, rice with malt and formula A were less affected by the temperature change. 3) Infant foods with malt(formula A ) ad with waxy rice maintained better freeze-thaw stability in terms of consistency and starch aggregation indicating that this infant food could be stored for a long term in the freezer section of the home refrigeratory without adverse effect on the product quality. 4) From the above experiments, it would necessarily follow that infant food can be easily made at home the food-stuffs generally available around us, and that the easiest and safest way to store them lies in making them into semisolid state, and in keeping them in frozen state.

• Journal of Life Science
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• v.8 no.5
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• pp.526-531
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• 1998

In this study, the composition and characteristics of poly-$\beta$-hydroxybutyrate (PHB) biosynthesized by Actinobacillus sp. EL-9 are investigated. PHB produced by Actinobacillus sp. EL-9 was identified as the homopolymer of 3-hydroxy-butyric acid (PHB) by infrared spectroscopy and nuclear magnetic resonance spectroscopy analysis. The melting tem-perature (T$_{m}$), and crystallization temperature(T$_{c}$) of PHB was 169.7$^{\circ}C$ and 69.13$^{\circ}C$, respectively. The viscosity on he basis of Brookfield viscometer was 6.01 ㎗/g. The viscosity-average molecular weight estimated by Mark-Ho-wink-Sakurada equation was 1.08$\times$10$^{6}$ ($\pm$3,000).00).