Rheological behavior of porous pharmaceutical materials: Linking torque profiles during wet massing to water diffusion coefficients and penetration time

Water absorption characteristics of two newly-released maize hybrids, Obatanpa and Mamaba, during soaking were measured at four temperatures of 30, 40, 50 and 60ºC. The absorption kinetics followed the Fick's law of diffusion during the first hours of soaking. The values determined for water diffusion coefficients varied from 7.31 x 10-12 to 9.33 x 10-12 m2/s and from 6.30 x 10-12 to 8.25 x 10-12 m2/s for Obatanpa and Mamaba respectively. An Arrheniustype equation was used to relate the diffusion coefficient of Obatanpa and Mamaba to temperature, and the energy of activation for Obatanpa and Mamaba was estimated. The values determined were 6.54 kJ/mol and 6.82 kJ/mol for Obatanpa and Mamaba respectively.

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Brain-water diffusion coefficients reflect the severity of inherited prion disease

Neurology ◽

10.1212/wnl.0b013e3181d0cc47 ◽

2010 ◽

Vol 74 (8) ◽

pp. 658-665 ◽

Cited By ~ 7

Author(s):

H. Hyare ◽

S. Wroe ◽

D. Siddique ◽

T. Webb ◽

N. C. Fox ◽

...

Keyword(s):

Prion Disease ◽

Diffusion Coefficients ◽

Water Diffusion ◽

Brain Water

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Deconvolution of Compartmental Water Diffusion Coefficients in Yeast-Cell Suspensions Using Combined T1 and Diffusion Measurements

Journal of Magnetic Resonance ◽

10.1006/jmre.2002.2527 ◽

2002 ◽

Vol 156 (1) ◽

pp. 52-63 ◽

Cited By ~ 32

Author(s):

Matthew D. Silva ◽

Karl G. Helmer ◽

Jing-Huei Lee ◽

Sam S. Han ◽

Charles S. Springer ◽

...

Keyword(s):

Yeast Cell ◽

Diffusion Coefficients ◽

Water Diffusion ◽

Cell Suspensions ◽

And Diffusion

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A simple method for measuring water diffusion coefficients in conducting polymers

10.1109/stsm.1994.835411 ◽

1994 ◽

Author(s):

P. Passiniemi

Keyword(s):

Conducting Polymers ◽

Diffusion Coefficients ◽

Water Diffusion ◽

Simple Method

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Inverse analysis of the transient bound water diffusion in wood

Holzforschung ◽

10.1515/hf.2005.007 ◽

2005 ◽

Vol 59 (1) ◽

pp. 38-45 ◽

Cited By ~ 42

Author(s):

Wiesław Olek ◽

Patrick Perré ◽

Jerzy Weres

Keyword(s):

Experimental Data ◽

Diffusion Coefficients ◽

Inverse Analysis ◽

Bound Water ◽

Water Diffusion ◽

European Species ◽

Alternative Approach ◽

Transfer Problems ◽

Bound Water Content ◽

Water Diffusion Coefficient

Abstract The methods so far applied to determine the bound water diffusion coefficient in wood do not provide credible results on this coefficient as well as on the boundary condition. An alternative approach based on the concept of solving the inverse transfer problems was recently applied. Two European species were investigated in the present study. A series of sorption experiments was performed and followed by the numerical identification of the coefficients. Several case studies were carried out for the constant and bound water content dependent diffusion coefficients. The obtained results were validated by comparison to a set of experimental data.

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Empirical Dissolution Rate Law for the Glass R7T7 Contacting Halite- and Silica-Saturated Brines

MRS Proceedings ◽

10.1557/proc-257-143 ◽

1991 ◽

Vol 257 ◽

Cited By ~ 21

Author(s):

B. Grambow ◽

W. Lutze ◽

R. Müller

Keyword(s):

Time Dependence ◽

Dissolution Rate ◽

Diffusion Coefficients ◽

Water Diffusion ◽

Square Root ◽

Borosilicate Glasses ◽

Rate Law ◽

Apparent Diffusion Coefficients ◽

Apparent Diffusion

ABSTRACTWe report on the time dependence of release of glass constituents during static dissolution experiments with the COGEMA glass R7T7 in saline MgCl2 and NaCl dominated solutions at temperatures between 110 and 190°C. The experiments were performed at high S/V values to ensure silica saturation almost from the start of the tests. The results show a square root of time dependence indicating diffusion as rate-controlling with apparent diffusion coefficients similar to that of water diffusion in alkali silicate, borosilicate glasses or long-term weathered obsidians.

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