• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.38-43
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• 1990

Effects of concentration (5-8%, db) and heating temperature $(80^{\circ}C-95^{\circ}C)$ on rheological of mungbean starch were examined. The pasting curve by amylograph revealed no peak viscosity and the viscosity continued to increase during cooking, regardless the starch concentrations. Mungbean starch paste showed a pseudoplastic flow behavior with yield stress. The consistency index of paste increased as the heating temperature was raised at a given concentration. However, flow behavior index showed opposite trend. The percent sag of starch gel stored at $4^{\circ}C$ decreased with the increase of concentration and heating temperature. The firmness of fresh gel prepared from 7 and 8% starch suspensions by heating at $95^{\circ}C$ for 15 min with amylograph was about 2-times higher than that of 6% gel. However, the time constant, reciprocal of rate constant, of starch gels during aging at $4^{\circ}C$ was not significantly influenced by concentrations and heating temperatures.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.780-786
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• 2008

Effect of acetylated starches (acetylated rice starch and acetylated tapioca starch) on rheological properties of hot pepper-soybean paste (HPSP) at different mixing ratios of rice flour (RF) and acetylated starch (AS) (10/0, 9/1, 8/2, and 7/3) was evaluated in steady and dynamic shear. All HPSP samples at $25^{\circ}C$ exhibited shear-thinning (n=0.31-0.36) and thixotropic behavior with high yield stresses and their steady flow curves were well described by power law and Casson models. The presence of AS resulted in the decrease in consistency index (K), apparent viscosity (${\eta}_{a,100}$), and yield stress (${\sigma}_{oc}$), and their predominant decreases were noticed at higher ratio of RF to AS (7/3 ratio). Arrhenius temperature relationship represents variation with temperature in the range of $5-35^{\circ}C$ with the high determination coefficients ($R^2=0.97-0.99$). Dynamic moduli (G', G", and ${\eta}^*$) values of HPSP samples mixed with AS were lower than those of HPSP with no added AS within the experimental range of frequency (0.63-62.8 rad/sec). Steady and dynamic shear rheological properties of HPSP samples seem to be greatly influenced by the presence of acetylated starch.

• Computers and Concrete
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• v.32 no.2
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• pp.185-206
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• 2023

This article aimed to explore the optimization of mineral admixtures and retarding admixture for high-performance concrete. In essence, fresh concrete can be regarded as a mixture in which both coarse and fine aggregates are suspended in a cement-based matrix paste. Based on this view, the test procedure was divided into three progressive stages of binder paste, mortar, and concrete to explore their rheological behavior and mechanical properties respectively. At each stage, there were four experimental control factors, and each factor had three levels. In order to reduce the workload of the experiment, the Taguchi method with an L9(3⁴) orthogonal array and four controllable three-level factors was adopted. The test results show that the use of the Taguchi method effectively optimized the composition of high-performance concrete. The slump of the prepared concrete was above 18 cm, and the slump flow was above 50 cm, indicating that it had good workability. On the other hand, the 28-day compressive strength of the hardened concretes was between 31.3-59.8 MPa. Furthermore, the analysis of variance (ANOVA) results showed that the most significant factor affecting the initial setting time of the fresh concretes was the retarder dosage, and its contribution percentage was 62.66%. On the other hand, the ANOVA results show that the most significant factor affecting the 28-day compressive strength of the hardened concretes was the water to binder ratio, and its contribution percentage was 79.05%.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.45-50
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• 1998

This study is aimed for investigating the rheology property and fluidity of superplasticizer which is necessary using for high flowing concrete fluidity establishment. Therefore, this study is analysis the rheology property and fluidity by different according temperature and elapsed time. From the results, the fluidity and rheology value were different according temperature. Over 2$0^{\circ}C$, the flow value of A, B, C, D, E type is increased, according as the increase of temperature, but the flow value of F type is decreased.

• International Journal of Concrete Structures and Materials
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• v.8 no.4
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• pp.269-278
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• 2014

When concrete is being transported through a pipe, the lubrication layer is formed at the interface between concrete and the pipe wall and is the major factor facilitating concrete pumping. A possible mechanism that illustrates to the formation of the layer is the shear-induced particle migration and determining the rheological parameters is a paramount factor to simulate the concrete flow in pipe. In this study, numerical simulations considering various rheological models in the shear-induced particle migration were conducted and compared with 170 m full-scale pumping tests. It was found that the multimodal viscosity model representing concrete as a three-phase suspension consisting of cement paste, sand and gravel can accurately simulate the lubrication layer. Moreover, considering the particle shape effects of concrete constituents with increased intrinsic viscosity can more exactly predict the pipe flow of pumped concrete.

• Journal of the Korean Applied Science and Technology
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• v.32 no.4
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• pp.724-730
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• 2015

For ex-vivo diabetic control, the voltammetric diagnosis of glucose (GU) was conducted with a modified carbon nanotube paste electrode, using handheld analytical circuits. The optimum analytical conditions were attained within the 0.5-4.0 ug/L working range and at the 0.06 ug/L detection limit, which system was interfaced to the feedback circuits and was applied to human urine for diabetic-patient diagnosis. It can be used for ex-vivo flow control analysis, vascular flow detection and other medicinal assays. The equations of the patients' urine are y=36.65x+12.13 and $R^2=0.987$, those of the healthy person of y= 2.5x+10.9 and $R^2=0.928$ (patients: 118 ug/L; healthy person: 12.34 ug/L).

• Journal of the Korean Applied Science and Technology
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• v.31 no.2
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• pp.210-217
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• 2014

For ex-vivo diabetic control, the voltammetric diagnosis of glucose (GU) was conducted with a modified carbon nanotube paste electrode, using handheld analytical circuits. The optimum analytical conditions were attained within the 0.5-4.0 ug/L working range and at the 0.06 ug/L detection limit, which system was interfaced to the feedback circuits and was applied to human urine for diabetic-patient diagnosis. It can be used for ex-vivo flow control analysis, vascular flow detection, and other medicinal assays.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.104-105
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• 2016

From the Industrial Revolution by past to the present, Carbon emission quantity increase rapidly around the globe. Depending on this status, Also global warming are accelerated rapidly, in order to solve this status, the Climatic Change Convention is held now on. So, On this study, Utilizing the BFS, HFA, DS that we get the basic data of the cementless paste.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.747-755
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• 2006

This study evaluated the microbiological hazard of three Korean rice cake products (Gaepidduk, Injulmi, Julpyon). Microorganisms testing was conducted in various phases of the product flow of Korean rice cakes preparation, food equipment, environment work and cook employees at small scale. The results showed the presence of redbean paste, soybean powder and oil at levels as high as $10^5$ CFU/g on the hazard analysis of rice cakes ingredients. High levels of coliforms were detected in Julpyon products after 24 hr. and on the cooker's aprons. Clinical bacteria were not detected in any of the rice cakes. We concluded that there is a strong requirement for education related to personal hygiene for the production of hygienic rice cake products and for the publics health.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1254-1261
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• 1999

The influence of addition of arrow(Pueraria hirsuta Matsum) root flour and its fractions by ultrafiltration on the flow properties of the rice flour-water systems were investigated. The flow properties of rice flour pastes during cold storage$(5^{\circ}C)$ were measured and the components from arrow root flour responsible for changes of flow properties were screened. Addition of arrow root flour significantly changed the flow properties of rice flour pastes. Permeate fractions by ultrafiltration, representing low molecular weight component fraction, significantly affected the flow property of rice flour paste stored at $5^{\circ}C$. Addition of permeate fraction to rice flour pastes rapidly decreased the consistency index, yield stress and pseudoplasticity, and showed a stability of flow property during storage suggesting the retardation of rice starch retrogradation. Permeate fractions of ultrafiltration were identified as puerarin, daidzein and daidzin known to representive isoflavonoid from arrow root.