• Advances in concrete construction
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• v.6 no.6
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• pp.561-583
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• 2018

A variety of polycarboxylate ether (PCE)-based superplasticizers are commercially available. Their influence on the rheological retention and slump loss in respect of concrete differ considerably. Fluidity and slump loss are the cardinal features responsible for the quality of concrete. These are related to the dispersion of cement particles and the hydration process which are greatly influenced by type of polycarboxylate ether (PCE)-based superplasticizers. On the backdrop of relatively less studies in the context of rheological retention of high strength self-consolidating concrete (HS-SCC), the experimental investigations were carried out aiming at quantifying the effect of the six different PCE polymers (PCE 1-6) on the rheological retention of HS-SCC mixes containing two types of Ordinary Portland Cements (OPC) and unwashed crushed sand as the fine aggregate. The tests that were carried out included $T_{500}$, V-Funnel, yield stress and viscosity retention tests. The supplementary cementitious materials such as fly ash (FA) and micro-silica (MS) were also used in ternary blend keeping the mix paste volume and flow of concrete constant. Low water to binder ratio was used. The results reveal that not only the PCEs of different polymer groups behave differently, but even the PCEs of same polymer groups also behave differently. The study also indicates that the HS-SCC mixes containing PCE 6 and PCE 5 performed better as compared to the mixes containing PCE 1, PCE 2, PCE 3 and PCE 4 in respect of all the rheological tests. The PCE 6 is a new class of chemical admixtures known as Polyaryl Ether (PAE) developed by BASF to provide better rheological properties in even in HS-SCC mixes at low water to binder mix. In the present study, the PCE 6, is found to help not only in reduction in the plastic viscosity and yield stress, but also provide good rheological retention over the period of 180 minutes. Further, the early compressive strength properties (one day compressive strength) highly depend on the type of PCE polymer. The side chain length of PCE polymer and the fineness of the cement considerably affect the early strength gain.

• Preventive Nutrition and Food Science
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• v.10 no.3
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• pp.231-238
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• 2005

A standard $1\%$ w/v solution of CM-chitosan made from squid pen was added to milk at levels of $0.5\sim3\%$ (v/v) to improve the yield and rheological properties of cottage cheese by whey protein retention. Cheese curd did not form at levels higher than $3\%$ (v/v) CM-chitosan standard solution. Yield and total protein of cottage cheese increased up to $2\%\;by\;11\;to\;42\%\;and\;17\;to\;38\%$ respectively, compared to control cheese. Whey protein losses were decreased by 11 to $42\%$ and thus accounted for all of the increase in yield. Anomalous results were obtained at the $0.8\%$ level, which neither improved yield or whey protein retention nor stabilized rheological parameters, and at the $0.5\%$ level, which improved yield and total protein without increasing whey protein retention. Elasticity and cohesiveness of CM-chitosan-containing cheese were generally improved and stabilized during storage. Monitoring of cheese chromaticity values for four weeks revealed a delay in the onset of yellowing in cheeses with CM-chitosan compared to the controls, while the concentration of added CM-chitosan had little influence on cheese chromaticity. The addition of CM-chitosan solution could be applied directly to industrial scale cottage cheese-making without the need for any modification of the production process.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.3
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• pp.440-450
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• 2015

Effects of Doenjang and Chunggukjang on rheological properties of bread flour were investigated based on falling number, RVA, farinogram, colorimeter, rheofermentometer and SEM. The falling number of bread flour was highest among all samples, and mixed flours containing Chunggukjang showed lower falling number than Doenjang. RVA showed that initial pasting temperatures of the control mixed flour of Doenjang and Chunggukjang increased sequentially, whereas peak viscosities were reversed and final viscosities showed similar results. In the farinogram, consistencies and water absorptions decreased with increasing quantity of Doenjang and Chunggukjang. Developments, stabilities, time to breakdowns and farinogram quality numbers of the mixed flour containing Doenjang were higher than those of Chunggukjang and greater addition decreased values. In the rheofermentometer test, height of maximum dough development of mixed flours containing Chunggukjang were lower than that of flours containing Doenjang. Total volumes, retention volumes and retention coefficients of mixed flours containing Doenjang and Chunggukjang were lower compared to the control. For features, SEM showed that mixed flour containing Chunggukjang showed a faded boundary compared to flour containing Doenjang. All of results showed that the various activities of Chunggukjang were more potent than those of Doenjang.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.139-147
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• 2003

Coater runnability of the paper coating and final product properties can be affected by the immobilization of coating color and the dewatering into the base paper. During the dewatering, the rheological properties and solids content of a coating are dramatically changed. For the purpose of obtaining better coater runnability and high quality of coater paper many papermakers are trying to improve the water retention of paper coatings by using some additives such as thickener and co-binder. In this study, we tried to investigate the rheological properties and the immobilization point of coatings with immobilization cell during the dewatering of coatings.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.1
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• pp.180-184
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• 2013

Recently, silk sericin has attracted the attention of researchers owing to its useful properties as a biomaterial including 1) good wound healing and cell activities, 2) fast gelation character, and 3) high water retention property. In the present study, silk sericin was prepared using different extraction times in hot water and the effect of extraction time on the rheological properties of sericin solutions and gels was examined. It was found that the production yield of sericin increased with extraction time. The shear viscosity of sericin solutions and gels decreased with increasing extraction time due to a decrease in sericin molecular weight. When the sericin solution transformed to a gel, the viscosity increased and the shear thinning behavior was more evident. In addition, the shear stress measurements indicated that the slip between the sericin samples and the measuring plate of the rheometer was increased by the gelation of sericin. The compression strength of sericin gel could be increased remarkably (by more than 100 fold) by preparation using the freezing and thawing method.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.271-276
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• 2003

This study is about the rheological properties of cement slurry using admixtures. The variables are the type of cement(Type I, II, IV, V) and the substitution ratio of admixtures such as fly ash and slag. As a result of measuring the fluidity of various types of cement slurry at the early stage, type 2, type 4 and type 5 showed the similar property. The fluidity of type 1 and ternary blended cement was low. it is thought that it is because of the high $C_3$A content. The cement slurries containing mineral admixtures were superior in the property of fluidity retention.

• Journal of the Korean Wood Science and Technology
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• v.24 no.4
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• pp.82-86
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• 1996

This study was performed to elucidate the effect of degree of substitution and degree of polymerization of CMC on the rheological characteristics of coating color which is consisted of calcium carbonate as pigment. The results were as follows: 1. It appeared that DP of CMC rather DS has an effect on the low shear viscosity of coating color. 2. According as shear rate increased, the effect of DP and DS on high shear viscosity of coating color decreased. 3. According to increasing DS and DP, the water retention of coating color increased.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.587-593
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• 2018

This study was carried out to investigate the effect of roasted rice bran (RRB) on the rheological properties of bread dough. According to farinograph analysis, the consistency of the control sample was greatest. There were no significant differences in water absorption (p<0.05). Lower values of development time, stability, and time to breakdown, which were affected, by the addition of RRB, were observed for RRB-containing dough samples, compared to the control dough sample. Addition of RRB significantly increased the mixing tolerance index (MTI). According to rheofermentometer analysis, the values of H'm, $T^{\prime}_1$, and retention volume decreased with increase in the amount of RRB added. According to the rapid visco analyzer (RVA) analysis, peak viscosity, holding strength, and setback values were greater in the control than in the RRB-containing samples. The addition of RRB to the flour influenced rheological properties like fermentation volume and acidity. The total acidity increased with the increase in the amount of RRB added. The present study has indicated that there was no significant difference between the rheological properties of the control and 5% RRB-containing dough samples. Therefore, the addition of 5% RRB could be an effective way to produce functional flour bread without affecting its desirable physical properties.

• Magazine of the Korea Concrete Institute
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• v.7 no.5
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• pp.189-199
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• 1995

Naphthalene sulfonated condensate has been widely used as a superplasticizer for cement and concrete, but the application was limited due to its large slump loss with elapsed time. To complement this demerit of NSF, polycarboxylic acid copolymer from nlaleic anhydride and acryl~c acid(MA) was synthesized to retain the mobility of cement and concrete, and then mixed with NSF. The physical properties, such as fluidity, fluidityretention and rheology, were measured by applying these admixtures to cement paste as a function of elapsed time. And also compressive strength of mortar was measured with curing time. NIv-l and NM-2 containing 10, 20 wt% of MA respectively had a excellent fluidity and a fluidity- retention. In rheological property, the increases of shear stress and viscosity with elapsed time were delayed with the increasing of shear rate in cornparision with NSF only. The marked slump loss of cement paste could be controlled by these admixture. Also the added ainount of admixture and the ratio of water to cement affected these properties.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.406-411
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• 2007

In this study the replacement of wheat flour with 5 to 30% black rice flour was tested to examine its effect on sponge cake making properties. We evaluated the effects of the substitutions on various quality parameters of the cake, such as physicochemical and rheological properties, cake making quality, and texture characteristics. The water holding capacity value increased with increasing amounts of black rice flour, whereas the alkaline water retention capacity, Pelshenke value and sedimentation value decreased. The mixograph peak time and peak height, and the Rapid Visco Analyser peak, minimum, and final viscosity decreased with the addition of black rice flour. Increasing proportions of black rice flour resulted in reduced loaf volume. However, replacing 15% of the wheat flour with black rice flour did not significantly affect the characteristics of the sponge cake. The textural characteristics of the sponge cake crumb were influenced by the addition of black rice flour, and sponge cakes containing the additives showed increases in hardness, gummines, and chewiness.