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Showing 1 to 20 of 20 for “"Shear History"”.
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Interactions Between Portland Cements and Carboxylated and Naphthalene-Based Superplasticizers
… paste to be dispersed. The differences in the shear history between the concretes and the pastes possibly explain such discrepancies in admixture dosages.
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Rheology and Microstructure of Concentrated Suspensions of Plate-Shaped Colloidal Particles
… equal to 8. These suspensions demonstrate shear thickening at $\phi \ge$ 0.50 and also have a shear history dependent elastic modulus, G$\sp\prime.$ In the shear thinning region G$\sp\prime$ decreases with increasing shear rate. In the shear thickening region the modulus increases rapidly. …
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Shear thickening and microstructures of concentrated charge stabilized suspensions
… properties and microstructures as function of shear rates is constructed for the first time. A parameter to measure the degree of suspension order under shear is established. The rapid increase of suspension viscosity as the shear rate increases is examined as function of volume fraction, …
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Shear behavior and microstructures of confined colloidal suspensions
… electrostatic potential. Stress versus shear rate behavior is examined as a function of particle volume fraction, gap size, and shear history. Microstructures for systems at equilibrium and under shear are investigated by direct observation of particle configurations and by scattering …
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Two-Dimensional Transient Flows and Stability of Concentrated Suspensions of Clay Particles and Rheology
… using a state-of-the-art rheometer show that the shear history of concentrated suspensions of clay particles can be divided into three regions: solid-rigid, nearly Newtonian, and shear-thinning regions. The nearly Newtonian region is very narrow in shear rate compared to the shear thinning region. …
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Organic Fillers in Phenol-Formaldehyde Wood Adhesives
… the adhesive formulations as a function of shear history, filler type, and filler particle size. Relative to alder bark and walnut shell, the unique behavior of corn cob residue was discussed with respect to chemical composition. Alder bark and walnut shell exhibited similar effects with a …
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The study of shear inactivation of dextransucrase preparation from Leuconostoc mesenteroides
… levansucrase was determined to be less than 2%. Shear inactivation study was performed on a batch reactor after subjecting the enzyme solution to a shear rate of 1046 second⁻¹ in the couette viscometer for several different periods of shear exposure time. The kinetic data showed dextransucrase …
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The rheological and honing characteristics of polyborosiloxane/grit mixtures.
… the different media types by the manufacturer. A shear history effect is also exhibited in each of the polymer types.</p>
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Mathematical modelling and optimisation of the formulation and manufacture of aggregate food products
… granola products were incorporated: i) a high shear mixing granulation stage (in a designated granulator) followed by drying/toasting in an oven. ii) a continuous fluidised bed followed by drying/toasting in an oven. In addition, the particle breakage of granola during pneumatic conveying …
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Extrusion honing using mixtures of polyborosiloxanes and grit
… a slit-die and a capillary rheometer. The shear history of the polyborosiloxane prior to testing with the capillary rheometer was found to significantly affect the results produced. At shear strain rates up to 100 s-1 and a temperature of 30°C the rheology of the polyborosiloxane has been …
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The Transient Flow Rheology and Instabilities of Polyethylene Melts
… the linear and non-linear behaviour (for lower shear rates) of these polyethylenes were determined from dynamic (oscillatory) experiments and stepstrain experiments performed using the Rheametrics (RDS), parallel-plate rheameter. Similar measurements using a capillary geometry with the MPR were …
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The Transient Flow Rheology and Instabilities of Polyethylene Melts
… the linear and non-linear behaviour (for lower shear rates) of these polyethylenes were determined from dynamic (oscillatory) experiments and stepstrain experiments performed using the Rheametrics (RDS), parallel-plate rheameter. Similar measurements using a capillary geometry with the MPR were …
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Flow of viscoelastic fluids through banks of cylinders: an experimental and numerical investigation
… constitutive equations were fit to the steady shear viscosity of a LLDPE melt and a LDPE melt. The PTT and RS models were also fit to uniaxial extensional stress growth data for each melt. The predictions of the pressure drop by means of the finite element calculations and a capillary model …
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Optimisation of granola breakfast cereal manufacturing process by wet granulation and pneumatic conveying
… granola products were incorporated: a) a high shear mixing granulation process followed by drying/toasting in an oven. b) a continuous fluidised bed followed by drying/toasting in an oven. In high shear granulation the influence of process parameters on key granule aggregate quality attributes …
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Rheology and Flow Behaviour of Non-Newtonian, Polymeric Fluids in Capillaric and Porous Media: Aspects Related to Polymer Flooding for Enchanced Recovery of Heavy Oil
… degree of hydrophobicity; however, solution shear history, salinity and temperature were found to have a slightly negative effect. Compared to traditional HPAMs, a medium density HAP showed an earlier onset of elastically-dominated flow as determined by its increased elasticity, …
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Rheology And Organic Filler Interactions in Phenolic Resin Formulations
… polymer has seen many applications throughout history, including jewelry, electric wire insulation, and resins used to make adhesives. Today, PF resins are still crucial components used in the wood products industry. These PF resins are formulated into adhesives used to make plywood and various …
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Study of the time-dependent rheological behaviour of lead-free solder pastes and flux mediums used for flip-chip assembly applications
… In general, the breakdown of the structure with shear results in a decrease in apparent viscosity. Recovery after shear is generally a very slow process and depends on the intensity of the breakdown and previous shear history. The work reported in this thesis on the characterisation and modelling …
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Synthesis and characterisation of polyamide 6 blends made by reactive extrusion
… were also employed to influence the thermal and shear history of the reaction mixture. Differential scanning calorimetry and wide angle X-ray diffraction techniques were used to characterise the thermal properties and crystalline order of the polymerisation product. It was observed that the …
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Mechanism of nonlinear biodynamic response of the human body exposed to whole-body vibration
… voluntary periodic movement. The effect of shear history and vibration magnitude on the apparent mass was investigated using 12 subjects in a relaxed semi-supine posture assumed to involve less muscle activity than static sitting and standing. The semi-supine subjects were exposed to two …
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Rheological characterization of lubricants in automotive industries through development of a novel capillary breakup extensional rheometer
… viscosity index (1OW-30) appearing identical in shear flow, as well as having similar surface tensions are selected. Capillary thinning measurements show that these fluids can be differentiated by the onset of strain-rate-thickening close to breakup, corresponding to the dimensionless Weissenberg …