Rheological Properties of Sodium Metatungstate in Aqueous Solutions

2014 ◽  
Vol 960-961 ◽  
pp. 249-253
Author(s):  
Jian Gang Ku ◽  
Kui He ◽  
Hui Huang Chen ◽  
Wen Yuan Liu
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Theoretical Basis ◽  
Flow Simulation ◽  
Density Fractionation ◽  
Flow Curves ◽  
Fixed Temperature ◽  
Effects Of Temperature ◽  
Increasing Temperature ◽  
Pseudoplastic Fluids

Sodium metatungstate (SMT) solution is an inorganic heavy liquid which is widely used in density fractionation. However, rheological properties of aqueous SMT solutions have never been fully researched. The objective of the present work was to study the rheological properties of aqueous SMT solutions and effects of temperature and density on the apparent viscosity. The steady flow experimental data was fitted using Herschel-Bulkley model. The results show that aqueous SMT solutions of different density are pseudoplastic fluids and the flow curves of SMT solutions were described by the Hershel-Bulkley equation. The apparent viscosity decreases monotonically with increasing temperature under the same density and increases exponentially with increasing density at the fixed temperature. Rheological properties of aqueous SMT solutions can be applied in the calculation of density fractionation efficiency and provides a theoretical basis for flow simulation.

scholarly journals Effects of WMA Additive on the Rheological Properties of Asphalt Binder and High Temperature Performance Grade

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Jiupeng Zhang ◽  
Guoqiang Liu ◽  
Li Xu ◽  
Jianzhong Pei
Keyword(s):  
Critical Temperature ◽  
Rheological Properties ◽  
Asphalt Binder ◽  
Aging Effect ◽  
Asphalt Binders ◽  
Short Term ◽  
Performance Grade ◽  
Temperature Performance ◽  
Effects Of Temperature ◽  
Increasing Temperature

Sasobit additives with different dosages were added into 70# and 90# virgin asphalt binders to prepare WMA binders. The rheological properties, includingG∗andδ, were measured by using DSR at the temperature ranging from 46°C to 70°C, and the effects of temperature, additive dosage and aging onG∗/sin⁡δ, critical temperature, and H-T PG were investigated. The results indicate that WMA additive improvesG∗but reducesδ, and the improvement on 70# virgin binder is more significant.G∗/sin⁡δexponentially decreases with the increasing temperature but linearly increases with the increasing additive dosage. Aging effect weakens the interaction between binder and additive but significantly increases the binder’s viscosity; that is whyG∗/sin⁡δis higher after short-term aging. In addition, the critical temperature increases with the increasing additive dosage, and the additive dosage should be more than 3% and 5% to improve H-T PG by one grade for 70# and 90# virgin binder, respectively.

Performance Study of Coal Water Slurry

2014 ◽  
Vol 716-717 ◽  
pp. 16-19
Author(s):  
Ke Gai ◽  
Hui Li Qi ◽  
Dong Ping Ma ◽  
Wen Li Liang
Keyword(s):  
Rheological Property ◽  
Rheological Properties ◽  
Apparent Viscosity ◽  
Performance Study ◽  
Water Slurry ◽  
Coal Water Slurry ◽  
The Stability ◽  
Increasing Temperature

This paper is based on the research of the coal water slurry rheological property and stability. The influence of the concentration, additives and temperature on the rheological properties of the slurry has also been studied. The apparent viscosity increases with increasing concentration of coal water slurry, and decreases with increasing temperature. An introduction of additives can greatly improve the rheological properties of coal water slurry. The stability of coal water slurry increases with the increase of concentration, and the stability decreases with the increase of temperature. A proper amount of additives can improve its stability.

scholarly journals Effect of Maltodextrins on the Rheological Properties of Potato Starch Pastes and Gels

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Lesław Juszczak ◽  
Dorota Gałkowska ◽  
Teresa Witczak ◽  
Teresa Fortuna
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Potato Starch ◽  
Considerable Reduction ◽  
Flow Curves ◽  
Degree Of Polymerisation ◽  
Pasting Characteristics ◽  
Storage And Loss Moduli ◽  
Mechanical Spectra

The study examines the effects of maltodextrins saccharified to various degrees on some rheological properties of potato starch dispersions. Pasting characteristics, flow curves, and mechanical spectra were determined for native potato starch and for its blends with potato maltodextrins having dextrose equivalents (DE) of 10.5, 18.4, and 26.5. The results showed that medium-saccharified maltodextrin (DE = 18.4) gave the strongest effect, manifesting itself as a considerable reduction in the viscosity at pasting, a decrease in apparent viscosity during flow, and a decrease in the storage and loss moduli. Addition of high-(DE = 26.5) or low-(DE = 10.5) saccharified maltodextrins had a markedly smaller effect on the rheological properties of starch. The differences in the effects produced by the maltodextrins are closely connected to the degree of polymerisation of the maltooligosaccharides in the systems.

Rheological Properties of PAN and Silk Fibroin in Aqueous NaSCN Solutions

2012 ◽  
Vol 557-559 ◽  
pp. 1095-1098
Author(s):  
Jian Wang
Keyword(s):  
Rheological Properties ◽  
Silk Fibroin ◽  
Apparent Viscosity ◽  
Polymer Concentration ◽  
Solution Properties ◽  
Increasing Temperature

The rheological properties of polyacrylonitrile (PAN) and silk fibroin (SF) in the aqueous NaSCN Solutions were investigated in this study. The results show that the solutions possessed slightly pseudo-plastic solution properties. Their apparent viscosity increased with the increasing total polymer concentration, whereas all of these decreased with the increasing temperature. The viscosity of PAN/SF blend solutions decreased with the increase of the SF component.

Rheological Properties of Limited Enzymatic Hydrolyzed Wheat Gluten

2012 ◽  
Vol 550-553 ◽  
pp. 1535-1539
Author(s):  
Zhang Cun Wang ◽  
Le Jing Li ◽  
Xue Wei Zhao ◽  
Sheng Wen Cui
Keyword(s):  
Rheological Properties ◽  
Sodium Alginate ◽  
Apparent Viscosity ◽  
Xanthan Gum ◽  
Wheat Gluten ◽  
Shear Thinning ◽  
Effects Of Temperature ◽  
Complex Solutions

The rheological properties of Limited Enzyme-hydrolyzed Wheat Gluten (LHWG) and its complex solutions with xanthan gum (XG), sodium alginate (SA) or gelatin were researched by Brookfield DV-Ⅱ+Pro Viscometer. The results showed that they all exhibited typical shear-thinning behavior and the higher LHWG concentration, the more evident of the shear thinning was. The effects of temperature on the rheology of LHWG were very complicated based on the concentration. The apparent viscosity of 300 mg/mL LHWG (20°C) was higher than that of 100 mg/mL and 200 mg/mL, and showed fluctuation between 20°C and 90°C, which were strongly different from that of low LHWG solution. However, the rheological properties of LHWG were influenced slightly by shearing time.

Effect of Some Hydrocolloids on the Rheological Properties of Rye Starch

2004 ◽  
Vol 10 (2) ◽  
pp. 125-131 ◽  
Author(s):  
L. Juszczak ◽  
M. Witczak ◽  
T. Fortuna ◽  
A. Banachowicz
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Viscoelastic Properties ◽  
Guar Gum ◽  
Shear Stresses ◽  
Flow Curves ◽  
Arabic Gum ◽  
Pasting Characteristics ◽  
Mechanical Spectra ◽  
The One

The effect of three non-starch hydrocolloids (guar, carob and arabic gums) on some rheological properties of rye starch pastes/gels at a constant 6.5% concentration of polysaccharides was determined throughout: (i) pasting characteristics, (ii) flow curves and apparent viscosity–shear time curves at 50 C and (iii) mechanical spectra at 25 C. The presence of gums in the system modified the rheological properties of rye starch pastes/gels and these alterations depended on the type and concentration of the gum. The systems with guar and carob gums exhibited higher apparent viscosities during pasting and higher shear stresses during flow than the paste of native starch. The viscosity of the system with carob was bigger than the one with guar gum. The presence of arabic gum decreased the apparent viscosity of the system both during pasting and during flow. Replacing part of starch with a gum modified the viscoelastic properties of gels, the changes depended on the kind and concentration of the gum.

scholarly journals The influence of texture improver type and its addition level on rheological properties of goat’s milk yogurt

2007 ◽  
Vol 23 (5-6-2) ◽  
pp. 163-170 ◽  
Author(s):  
J. Domagała ◽  
M. Sady ◽  
T. Grega ◽  
D. Najgebauer-Lejko
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Sensory Quality ◽  
Rheological Parameters ◽  
Flow Index ◽  
Total Protein Content ◽  
Flow Curves ◽  
Rheological Models ◽  
And Control ◽  
Addition Level

Set yogurt from goat?s milk with addition of two texture improvers DSE 6693 and DSE 6694 from NZMP New Zealand, added in the amount of 1, 2and 3% and control yogurt without addition of texture improvers were produced. In yogurt determined sensory quality, pH, apparent viscosity and rheological properties. Flow curves obtained for produced yogurts were described by three rheological models: Ostwald de Waele, Herschel-Bulkley (H-B) and Casson. Addition of texture improver caused an increase in total solids and total protein content of milk for yogurt. Yogurt with texture improvers gave better sensory quality than control yogurt. The yogurt with 1% addition of DSE 6693 and with 2% addition of DSE 6694 had the best sensory quality. The increase in addition level of texture improvers caused an increase in apparent viscosity, consistency coefficient K, yield stress (except H-B model) and deviation from Newtonian flow (decrease of flow index n). Effect of type of improver was rather negligible, whereas its level addition considerably influenced the evaluated rheological parameters.

Survival of Endocronartium harknessii teliospores in a simulated airborne state

1989 ◽  
Vol 67 (3) ◽  
pp. 928-932 ◽  
Author(s):  
Kan-Fa Chang ◽  
P. V. Blenis
Keyword(s):  
Relative Humidity ◽  
Liquid Nitrogen ◽  
Long Distance ◽  
Spider Webs ◽  
Considerable Potential ◽  
Good Ability ◽  
Endocronartium Harknessii ◽  
Spore Longevity ◽  
Effects Of Temperature ◽  
Increasing Temperature

The effects of temperature and relative humidity (RH) on the survival of Endocronartium harknessii teliospores and the longevity of these spores out of doors during daylight hours were studied. In one experiment, fresh and liquid-nitrogen-stored spores of E. harknessii were impacted onto spider webs or plastic threads and incubated in darkness at temperatures of 6, 15, and 24 °C and RHs of 39 and 98%. Survival was measured after 1, 2, 4, 8, and 16 days. Spore longevity decreased with increasing temperature and was lower at 98 than at 39% RH. In a second experiment, spores were impacted onto spider webs and placed out of doors on clear days. Viability decreased linearly with time and averaged 33% after 12 h. The data suggest that E. harknessii has relatively good ability to survive in an airborne state and thus would have considerable potential for long distance spread.

FEM Comparative Analysis of Synchronous Rotor with Different Helix Angle in the Process of Mixing

2012 ◽  
Vol 501 ◽  
pp. 388-392
Author(s):  
Hui Guang Bian ◽  
Wei Shuai Lv ◽  
Chuan Sheng Wang
Keyword(s):  
Comparative Analysis ◽  
Theoretical Basis ◽  
Production Efficiency ◽  
Transient Flow ◽  
Flow Simulation ◽  
Helix Angle ◽  
Original Performance ◽  
Mixing Performance ◽  
Axial Tensile ◽  
Flow Mixing

The paper is used to analyze the structure of traditional synchronous rotor from the perspective which the helix angle between long edge and short edge has some difference. The specialized viscoelastic fluid software--Polyflow is used to dynamic simulation analyze the two different kinds of rotors during the process of flow mixing, and then to analyze the two kinds of rotor performance through the result of transient flow simulation which mixed for one second. The analysis revealed that the improved synchronous rotor had better axial tensile properties in the case of remaining the original performance basically unchanged. And that could improve mixing performance and the production efficiency of mixer more effectively. There will provide a theoretical basis for the optimization of the rotor configuration in future.

Effects of Temperature on Leaf Expansion in Sunflower

1982 ◽  
Vol 9 (2) ◽  
pp. 209 ◽  
Author(s):  
HM Rawson ◽  
JH Hindmarsh
Keyword(s):  
Field Studies ◽  
Leaf Expansion ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Leaf Position ◽  
Leaf Emergence ◽  
Temperature Regimes ◽  
Effects Of Temperature ◽  
Increasing Temperature ◽  
Relative Change

Five commercial cultivars of sunflower were grown in cabinets at three temperature regimes, 32/22, 27/17 and 22/12°C, and with 15-h and 11-h photoperiods, and expansion of leaves 5-15 was followed. Leaves appeared faster with increasing temperature (0.022 leaves day-1 °C-1) and with increasing daylength. Areas of individual leaves increased linearly up the plant profile and, although final area per leaf (Amax) decreased with increasing temperature, the relative change was similar for each leaf position. Cultivars maintained their ranking for Amax across temperatures, and these rankings agreed with those in previous field studies. Within each temperature regime, both the expansion rate of leaves and the duration of expansion increased with leaf position. As temperature increased, leaves grew for shorter periods with a change of 1.04 days °C-1, but under the photon flux density used (500 �mol m-2 s-1, or about 25% full sunlight) expansion rates were greatest at the lowest temperature. Expansion rates were only one-third of those in field studies at comparable temperatures, but durations were similar. Cultivars that achieved the largest Amax did so via faster rates of expansion and not via longer durations: only one cultivar differed from the mean (20 days) duration of leaf expansion. All cultivars reached floral initiation progressively earlier with extension of photoperiod from 10 to 15 h, with the change for the most sensitive cultivars being 8 days and for the least sensitive 5 days. Rates of leaf emergence were linked with this sensitivity.

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