Influence of Additives to Cement Slurry Rheological Property

Adding different kinds of additives will change rheological properties of cement slurry, same to the concrete. The relationship between fluid shear stress (Γ) and the shear rate (Ds) called rheological properties. In this paper we studied the influence of different additives (Olyacryamide, polycarboxylate superplasticizer , nanoCaCO3) on the slurry rheological properties and the effects of polyacrylamide on cement mortar liquidity.

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On the selected rheological properties of commercial ketchups

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200553020007 ◽

2005 ◽

Vol 53 (2) ◽

pp. 7-18 ◽

Cited By ~ 1

Author(s):

Libor Severa ◽

Jana Simeonovová ◽

Ivo Křivánek ◽

Jaroslav Buchar

Keyword(s):

Shear Stress ◽

Shear Rate ◽

Rheological Properties ◽

Fluid Shear Stress ◽

Fluid Shear ◽

Shear Rates ◽

High Shear Rates ◽

Typical Time ◽

Two Temperatures ◽

Thixotropic Fluid

The rheological properties of four different ketchups were determined. The viscosity, shear rate and shear stress were measured by use of Anton Paar DV-3 P Digital Viscometer and received data can be successfully characterized by several models, primarily by Hershel – Bulkley model. The ketchup was found to be a typical time-dependent thixotropic fluid. Shear stress and viscosity decrease with time of shear. Decrease during first 300 s is more significant than later decrease. The influence of spindle speed, shear rate potentially, on a sample viscosity was observed. The viscosity was rapidly changing during low speeds. The data were compared with Carreau model. Many other dependeces (low and high shear rates, difference between mixed and rested material etc.) were observed and modelled with satisfying results. Dependence of shear stress on shear rate under two temperatures was also examined. The tendency of increasing shear stress with increasing shear rate is evident. The samples were examined under temperature 22 °C and temperature 7 °C.

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Fluid shear stress combined with shear stress spatial gradients regulates vascular endothelial morphology

Integrative Biology ◽

10.1039/c7ib00065k ◽

2017 ◽

Vol 9 (7) ◽

pp. 584-594 ◽

Cited By ~ 15

Author(s):

Daisuke Yoshino ◽

Naoya Sakamoto ◽

Masaaki Sato

Keyword(s):

Shear Stress ◽

Fluid Flow ◽

Endothelial Cell ◽

Fluid Shear Stress ◽

Morphological Changes ◽

Vascular Endothelial ◽

Fluid Shear ◽

Spatial Gradients ◽

The Relationship

The magnitude of the relationship between shear stress (SS) and SS gradient plays an important role in regulating endothelial cell (EC) polarity and the resulting morphological changes in ECs in response to fluid flow.

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Faculty Opinions recommendation of Endothelial actin cytoskeleton remodeling during mechanostimulation with fluid shear stress.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13409065.14780078 ◽

2011 ◽

Author(s):

Martin A Schwartz

Keyword(s):

Shear Stress ◽

Actin Cytoskeleton ◽

Fluid Shear Stress ◽

Fluid Shear ◽

Cytoskeleton Remodeling

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Activation of integrins in endothelial cells by fluid shear stress mediates Rho-dependent cytoskeletal alignment

The EMBO Journal ◽

10.1093/emboj/20.17.4639 ◽

2001 ◽

Vol 20 (17) ◽

pp. 4639-4647 ◽

Cited By ~ 358

Author(s):

E. Tzima

Keyword(s):

Endothelial Cells ◽

Shear Stress ◽

Fluid Shear Stress ◽

Fluid Shear

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Epigenetic Changes During Mechanically Induced Osteogenic Lineage Commitment

Journal of Biomechanical Engineering ◽

10.1115/1.4029551 ◽

2015 ◽

Vol 137 (2) ◽

Cited By ~ 14

Author(s):

Julia C. Chen ◽

Mardonn Chua ◽

Raymond B. Bellon ◽

Christopher R. Jacobs

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Shear Stress ◽

Fluid Shear Stress ◽

Methylation Status ◽

Lineage Commitment ◽

Fluid Shear ◽

Osteogenic Lineage ◽

Osteogenic Markers ◽

Heterochromatin Structure

Osteogenic lineage commitment is often evaluated by analyzing gene expression. However, many genes are transiently expressed during differentiation. The availability of genes for expression is influenced by epigenetic state, which affects the heterochromatin structure. DNA methylation, a form of epigenetic regulation, is stable and heritable. Therefore, analyzing methylation status may be less temporally dependent and more informative for evaluating lineage commitment. Here we analyzed the effect of mechanical stimulation on osteogenic differentiation by applying fluid shear stress for 24 hr to osteocytes and then applying the osteocyte-conditioned medium (CM) to progenitor cells. We analyzed gene expression and changes in DNA methylation after 24 hr of exposure to the CM using quantitative real-time polymerase chain reaction and bisulfite sequencing. With fluid shear stress stimulation, methylation decreased for both adipogenic and osteogenic markers, which typically increases availability of genes for expression. After only 24 hr of exposure to CM, we also observed increases in expression of later osteogenic markers that are typically observed to increase after seven days or more with biochemical induction. However, we observed a decrease or no change in early osteogenic markers and decreases in adipogenic gene expression. Treatment of a demethylating agent produced an increase in all genes. The results indicate that fluid shear stress stimulation rapidly promotes the availability of genes for expression, but also specifically increases gene expression of later osteogenic markers.

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