11 research outputs found
The experimental and model values of storage modulus <i>G’</i>, loss modulus <i>G”</i> and tangent of loss angle <i>δ</i> as a function of oscillation frequency <i>ω</i>, for kuzu starch pastes when temperature and time of pasting were 90°C and 30 min, respectively.
<p>(a) the classical Kelvin-Voigt model (CKVM), (b) the fractional Kelvin-Voigt model with one springpot (FKVM1), (c) the fractional Kelvin-Voigt model with two springpots (FKVM2).</p
The goodness-of-fit indicators for rheological models presented in the work, for kuzu starch pastes when the temperature of pasting was 90°C.
<p>where: <i>t</i>–time of pasting; MPE—mean percentage error; MBE—mean bias error; RMSE—root mean square error; EF—modelling efficiency; χ<sup>2</sup>—chi-square test; CMM—the classical Maxwell model; FMM1—the fractional Maxwell model with one springpot; FMM2—the fractional Maxwell model with two springpots; MFMM2—the modified fractional Maxwell model with two springpots; CKVM—the classical Kelvin-Voigt model; FKVM1—the fractional Kelvin-Voigt model with one springpot, FKVM2—the fractional Kelvin-Voigt model with two springpots, MFKVM2—the modified fractional Kelvin-Voigt model with two springpots.</p><p>The goodness-of-fit indicators for rheological models presented in the work, for kuzu starch pastes when the temperature of pasting was 90°C.</p
Sample of 3% (w/v) kuzu starch paste for oscillatory and creep tests.
<p>Sample of 3% (w/v) kuzu starch paste for oscillatory and creep tests.</p
The experimental and model values of storage modulus <i>G’</i>, loss modulus <i>G”</i> and tangent of loss angle <i>δ</i> as a function of oscillation frequency <i>ω</i>, for kuzu starch pastes when temperature and time of pasting were 90°C and 30 min, respectively.
<p>(a) the classical Kelvin-Voigt model (CKVM), (b) the fractional Kelvin-Voigt model with one springpot (FKVM1), (c) the fractional Kelvin-Voigt model with two springpots (FKVM2).</p
The list of parameters of the proposed rheological models.
<p>where: <i>G</i><sup><i>0</i></sup><sub><i>N</i></sub>—the plateau modulus; <i>G</i><sub><i>e</i></sub>—the equilibrium modulus; <i>τ</i><sub><i>0</i></sub> —the shortest relaxation time; <i>τ</i><sub><i>m</i></sub>—the longest relaxation time; <i>α</i>, <i>β</i>–the fractional exponents; <i>η</i><sub><i>0</i></sub>—the Newtonian steady state shear viscosity; CMM—the classical Maxwell model; FMM1—the fractional Maxwell model with one springpot; FMM2—the fractional Maxwell model with two springpots; MFMM2—the modified fractional Maxwell model with two springpots; CKVM—the classical Kelvin-Voigt model; FKVM1—the fractional Kelvin-Voigt model with one springpot, FKVM2—the fractional Kelvin-Voigt model with two springpots, MFKVM2—the modified fractional Kelvin-Voigt model with two springpots; the sign of "+" means the presence of given parameter in the model.</p><p>The list of parameters of the proposed rheological models.</p
Kelvin-Voigt-type models.
<p>(a) classical; (b) fractional with one springpot; (c) fractional with two springpots.</p
Parameters of Kohlrausch-Williams-Watts equation estimated for 1% solutions of amylose and amylopectin in binary solvents.
<p>Parameters of Kohlrausch-Williams-Watts equation estimated for 1% solutions of amylose and amylopectin in binary solvents.</p
The effect of structural properties on rheological behaviour of starches in binary dimethyl sulfoxide-water solutions
<div><p>This research study analysed the rheological properties of potato amylose and potato amylopectin in binary solutions of the following water and dimethyl sulfoxide concentrations: 90% DMSO (1), 80% DMSO (2) and 50% DMSO (3), with preparation methodology involving the dissolution at the temperature of 98°C. The studies of dynamic light scattering on the biopolymer coils and the determination of main relaxation times of the solutions were carried out. For the amylose solutions, the fast relaxation phenomena are predominant. The results of the quality tests of the hysteresis loop showed, that the amylose solutions in the solvents (1) and (2) are rheologically stable and shear-thickened. The amylose solutions in solvents (3) reveal oscillatory alterations of viscosity in the time. Amylopectin solutions are characterized by 80% share of slow relaxation phenomena, very low diffusion coefficients and hydrodynamic radii in the range of 2000 nm. The amylopectin solutions are rheologically unstable.</p></div
The values of the parameters of the model (2a) for 1% AP solutions and of the model (2b) for 1% AM solutions (sample volume 0.4∙10<sup>−6</sup> m<sup>3</sup>).
<p>The values of the parameters of the model (2a) for 1% AP solutions and of the model (2b) for 1% AM solutions (sample volume 0.4∙10<sup>−6</sup> m<sup>3</sup>).</p
Molecular parameters of starches in binary solutions H<sub>2</sub>O/DMSO at 25°C.
<p>Molecular parameters of starches in binary solutions H<sub>2</sub>O/DMSO at 25°C.</p