Automatic recording of ultrasonic travel time using a computer-controlled pulse-echo overlap method

1987 ◽  
Vol 20 (11) ◽  
pp. 1400-1404 ◽  
Author(s):  
M A Buyukguclu ◽  
T Alper
Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5046
Author(s):  
Marzena Dzida

1-Butanol can be considered as a good fuel additive, which can be used at high pressures. Therefore, the knowledge of high-pressure thermophysical properties is crucial for this application. In this paper, new experimental data on the speed of sound in 1-butanol in the temperature range from 293 to 318 K and at pressures up to 101 MPa are reported. The speed of sound at a frequency of 2 MHz was measured at atmospheric and high pressures using two measuring sets operating on the principle of the pulse–echo–overlap method. The measurement uncertainties were estimated to be better than ±0.5 m·s−1 and ± 1 m·s−1 at atmospheric and high pressures, respectively. Additionally, the density was measured under atmospheric pressure in the temperature range from 293 to 318 K using a vibrating tube densimeter Anton Paar DMA 5000. Using the experimental results, the density and isobaric and isochoric heat capacities, isentropic and isothermal compressibilities, isobaric thermal expansion, and internal pressure were calculated at temperatures from 293 to 318 K and at pressures up to 100 MPa.


1986 ◽  
Vol 18 (7) ◽  
pp. 683-689 ◽  
Author(s):  
G Tardajos ◽  
M Diaz Peña ◽  
E Aicart

2002 ◽  
Vol 17 (7) ◽  
pp. 1785-1788 ◽  
Author(s):  
Ping Wen ◽  
Ru Ju Wang ◽  
Wei Hua Wang

The microstructure of Zr50.5Ti4.8Cu19.0Ni11.4Al14.3 bulk metallic glass (BMG) was investigated by high-resolution electron microscopy. The microstructure of the BMG is of homogeneous composition and short-range ordered microstructure. Using an ultrasonic technique with the pulse echo overlap method, the pressure-dependent acoustic velocities of the BMG have been measured up to 0.5 GPa. The elastic constants and their pressure dependence have been obtained. The isothermal equation of state (EOS) of the BMG is determined in terms of the Murnaghan form. With the results of the elastic constants and the EOS for those of its metallic components, the atomic configuration of the BMG is discussed.


2015 ◽  
Vol 79 (2) ◽  
pp. 285-294 ◽  
Author(s):  
F. Nestola ◽  
B. Periotto ◽  
C. Anzolini ◽  
G. B. Andreozzi ◽  
A. B. Woodland ◽  
...  

AbstractIn this work a single crystal of synthetic hercynite, FeAl2O4, was investigated by X-ray diffraction up to 7.5 GPa and at room temperature, in order to determine its pressure–volume equation of state. The unit-cell volume decreases non-linearly with a reduction of 3.4% (i.e. 18.43 Å3). The pressure–volume data were fitted to a third-order Birch-Murnaghan equation of state providing the following coefficients: V0 = 542.58(3)Å3, KT0 = 193.9(1.7) GPa, K' = 6.0(5). These results are consistent with previous investigations of Cr and Al spinels measured with the same experimental approach but the KT0 differs significantly from the experimental determination carried out more than 40 years ago by Wang and Simmons (1972) by the pulse echo overlap method. Our new results were used to redetermine the FeAl2O4(hercynite) = FeO(wüstite) + Al2O3(corundum) equilibrium in P–T space and obtain geobarometric information for Cr-Al spinels found as inclusions in diamond.


2003 ◽  
Vol 17 (02) ◽  
pp. 75-82
Author(s):  
T. V. CHONG ◽  
R. ABD-SHUKOR

Ultrasonic longitudinal and shear velocity in superconducting ErBa 2( Cu 3-x Zn x) O 7-δ (x = 0, 0.01 and 0.05) have been measured using the pulse-echo-overlap method at frequency 5–10 MHz in the temperature range 80–300 K. Longitudinal velocity hysteresis and elastic anomaly were observed in the x = 0 sample. Similar hysteresis was not observed in the x = 0.01 and 0.05 samples. The characteristic Debye temperature and electron–phonon coupling constant were calculated. The absence of hysteresis for longitudinal velocity in the x = 0.01 and 0.05 samples may be due to the spin correlation at the CuO 2 planes which affects the electron–phonon interaction.


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