Determination of transport parameters in air-saturated porous materials via reflected ultrasonic waves

2003 ◽  
Vol 114 (5) ◽  
pp. 2561 ◽  
Author(s):  
Z. E. A. Fellah ◽  
C. Depollier ◽  
S. Berger ◽  
W. Lauriks ◽  
P. Trompette ◽  
...  
1996 ◽  
Vol 61 (6) ◽  
pp. 844-855 ◽  
Author(s):  
Olga Šolcová ◽  
Petr Schneider

It was shown that the sampling loop, detector and connecting elements in the chromatographic set-up for determination of transport parameters by the dynamic method significantly influence the response peaks from columns packed with porous or nonporous particles. A method, based on the use of convolution theorem, was developed which can take these effects into account. The applicability of this method was demonstrated on the case of axial dispersion in a single-pellet-string column (SPSR) packed with nonporous particles. It is possible to handle also responses from columns packed with porous particles by a similar procedure.


1979 ◽  
Vol 15 (3) ◽  
pp. 316-317 ◽  
Author(s):  
V. M. Mel'nikov ◽  
�. A. Putnin'sh ◽  
V. O. Putninya ◽  
V. P. Karlivan

2016 ◽  
Vol 824 ◽  
pp. 18-26 ◽  
Author(s):  
Barbora Nečasová ◽  
Pavel Liška ◽  
Jiří Šlanhof ◽  
Martina Šimáčková

The authors of presented research case focused on possibilities of sealing porous as well as non – porous materials and analysed the measured results. It is the second article of the above mentioned authors dealing with sealed joints, however, in this case study the focus was placed on a group of industrially manufactured modified silyl polymer and polyurethane sealants. The research is based on the modified test procedure for the determination of adhesion and cohesion properties during maintained extension at variable temperatures, i.e. a high temperature of (70 + 2) °C and a temperature simulating freezing, i.e. (-20 + 2) °C, according to the European standard EN ISO 9047. The degree of specimen extension was set to amplitude of 20.0 % and the aim of the research case was to discover any differences that might appear in the resistance. The measured results demonstrate that there are significant differences between individual sealants in the results they provide in combination with specific material, e.g. wood appears to be a problematic substrate as well as glass cement or aluminium.


2012 ◽  
Vol 18 (3) ◽  
pp. 436-444 ◽  
Author(s):  
Esam T. Ahmed Mohamed ◽  
Albert E. Kamanyi ◽  
Mieczysław Pluta ◽  
Wolfgang Grill

AbstractVariations of the mechanical properties of red blood cells that occur during their life span have long been an intriguing task for investigations. The research presented is based on noninvasive monitoring of red blood cells of different ages performed by scanning acoustic microscopy with magnitude and phase contrast. The characteristic signature of fixed cells from groups of three different ages fractionated according to mass density is obtained from the acoustic microscope images, with the data represented in polar graphs. The analysis of these data enables the determination of averaged values for the velocities of ultrasound propagating in the cells from the different groups ranging from (1,681 ± 16) m s−1in the youngest to (1,986 ± 20) m s−1in the oldest group. The determined bulk modulus varies with age from (3.04 ± 0.05) GPa to (4.34 ± 0.08) GPa. An approach to determine for an age-mixed population of red blood cells, collected from a healthy person, the age of the individual cells and the age dependence of the cell parameters including density, velocity, and attenuation of longitudinal polarized ultrasonic waves traveling in the cells is demonstrated.


1981 ◽  
Vol 21 (12) ◽  
pp. 1657-1661 ◽  
Author(s):  
J.C. Couturaud ◽  
P.A. Holstein ◽  
M. Louis-Jacquet ◽  
B. Meyer ◽  
G. Thiell

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