vei 9, NTH 7034 Trondheim, Norway of segmented torsional resonators used to measure the high freq... more vei 9, NTH 7034 Trondheim, Norway of segmented torsional resonators used to measure the high frequency dynamic viscoelastic properties of e.g. polymer solutions.
Viscosity measurements have been carried out on dilute acid aqueous solutions of chitosan and of ... more Viscosity measurements have been carried out on dilute acid aqueous solutions of chitosan and of hydrophobically modified chitosan (HM-chitosan) with three different degrees of C12-aldehyde substitution. The experiments were performed in the presence of different amounts of the ...
The rheological properties of 1–50ppm poly α-olefins in Varsol 80 were studied using laminar and ... more The rheological properties of 1–50ppm poly α-olefins in Varsol 80 were studied using laminar and Taylor flows. In Taylor flow, all the studied poly α-olefins displayed polymer induced drag reduction and polymer scission. The measurements were carried out using a commercial rheometer equipped with a standard double-gap sample holder with axial symmetry. We find that this particular instrument even at
In studies of the viscoelastic properties of biopolymer solutions the total amount of polymer nee... more In studies of the viscoelastic properties of biopolymer solutions the total amount of polymer needed is often a crucial limiting factor. We here report on a new high-Q quartz torsional rod design that reduces the required sample volume to about 1 ml, while maintaining the instrument ...
Drag reduction in Taylor flow of polystyrene solutions is investigated using a commercial rheomet... more Drag reduction in Taylor flow of polystyrene solutions is investigated using a commercial rheometer equipped with a standard double-gap sample holder with axial symmetry. The dependence of drag reduction on various factors, including polymer molar mass, polymer concentration, and thermodynamic conditions is studied. Drag reduction induced by polystyrene in toluene is found to increase with increasing polymer concentration in the dilute concentration regime. It is also seen that molecules with high molar mass of the polymer promote drag reduction. In terms of hydrodynamic volume fraction normalisation, it is found that most of the drag reduction effect occurs at volume fractions below 0.2. It is observed that drag reduction is favoured by good thermodynamic conditions of the polymer-solvent system. Both the flow induced extension of the polymer chains and the hydrodynamic volume fraction occupied by the polymer molecules seem to play an important role for the drag reduction effect.
Hydrogen storage system Water electrolysis Stand-alone power system Demonstration plant Operation... more Hydrogen storage system Water electrolysis Stand-alone power system Demonstration plant Operational experience System simulation TRNSYS HYDROGEMS a b s t r a c t
vei 9, NTH 7034 Trondheim, Norway of segmented torsional resonators used to measure the high freq... more vei 9, NTH 7034 Trondheim, Norway of segmented torsional resonators used to measure the high frequency dynamic viscoelastic properties of e.g. polymer solutions.
Viscosity measurements have been carried out on dilute acid aqueous solutions of chitosan and of ... more Viscosity measurements have been carried out on dilute acid aqueous solutions of chitosan and of hydrophobically modified chitosan (HM-chitosan) with three different degrees of C12-aldehyde substitution. The experiments were performed in the presence of different amounts of the ...
The rheological properties of 1–50ppm poly α-olefins in Varsol 80 were studied using laminar and ... more The rheological properties of 1–50ppm poly α-olefins in Varsol 80 were studied using laminar and Taylor flows. In Taylor flow, all the studied poly α-olefins displayed polymer induced drag reduction and polymer scission. The measurements were carried out using a commercial rheometer equipped with a standard double-gap sample holder with axial symmetry. We find that this particular instrument even at
In studies of the viscoelastic properties of biopolymer solutions the total amount of polymer nee... more In studies of the viscoelastic properties of biopolymer solutions the total amount of polymer needed is often a crucial limiting factor. We here report on a new high-Q quartz torsional rod design that reduces the required sample volume to about 1 ml, while maintaining the instrument ...
Drag reduction in Taylor flow of polystyrene solutions is investigated using a commercial rheomet... more Drag reduction in Taylor flow of polystyrene solutions is investigated using a commercial rheometer equipped with a standard double-gap sample holder with axial symmetry. The dependence of drag reduction on various factors, including polymer molar mass, polymer concentration, and thermodynamic conditions is studied. Drag reduction induced by polystyrene in toluene is found to increase with increasing polymer concentration in the dilute concentration regime. It is also seen that molecules with high molar mass of the polymer promote drag reduction. In terms of hydrodynamic volume fraction normalisation, it is found that most of the drag reduction effect occurs at volume fractions below 0.2. It is observed that drag reduction is favoured by good thermodynamic conditions of the polymer-solvent system. Both the flow induced extension of the polymer chains and the hydrodynamic volume fraction occupied by the polymer molecules seem to play an important role for the drag reduction effect.
Hydrogen storage system Water electrolysis Stand-alone power system Demonstration plant Operation... more Hydrogen storage system Water electrolysis Stand-alone power system Demonstration plant Operational experience System simulation TRNSYS HYDROGEMS a b s t r a c t
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