Thermodynamics of haloarenes with n-hexane at 298.15–318.15 K: Density, ultrasonic speed and viscosity

2021 ◽  
Vol 321 ◽  
pp. 114366
Author(s):  
Anshu Sharma ◽  
Manju Rani ◽  
Sanjeev Maken
Keyword(s):  
Ultrasonic Speed

Influence of the applied pressure of the transducer on the propagation speed of the ultrasonic wave in wood

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Edgar V.M. Carrasco ◽  
Rejane C. Alves ◽  
Mônica A. Smits ◽  
Vinnicius D. Pizzol ◽  
Ana Lucia C. Oliveira ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Applied Pressure ◽  
Pressure Gauge ◽  
Eucalyptus Grandis ◽  
Propagation Speed ◽  
Ultrasonic Waves ◽  
Ultrasonic Speed ◽  
Wave Propagation Speed ◽  
Propagation Technique ◽  
Non Destructive

Abstract The non-destructive wave propagation technique is used to estimate the wood’s modulus of elasticity. The propagation speed of ultrasonic waves is influenced by some factors, among them: the type of transducer used in the test, the form of coupling and the sensitivity of the transducers. The objective of the study was to evaluate the influence of the contact pressure of the transducers on the ultrasonic speed. Ninety-eight tests were carried out on specimens of the species Eucalyptus grandis, with dimensions of 120 × 120 × 50 mm. The calibration of the pressure exerted by the transducer was controlled by a pressure gauge using a previously calibrated load cell. The robust statistical analysis allowed to validate the experimental results and to obtain consistent conclusions. The results showed that the wave propagation speed is not influenced by the pressure exerted by the transducer.

Applications of Densiometry, Ultrasonic Speed Measurements, and Ultralow Shear Viscosimetry to Aqueous Fluids

2000 ◽  
Vol 104 (15) ◽  
pp. 3463-3470 ◽  
Author(s):  
Gerhard Fritz ◽  
Günther Scherf ◽  
Otto Glatter
Keyword(s):  
Ultrasonic Speed

scholarly journals Optimized Blood Volume Monitoring during Hemodialysis Procedure based on Ultrasonic Speed Measurement

2019 ◽  
Vol 9 (3Jun) ◽  
Author(s):  
V. R Nafisi ◽  
M Eghbal
Keyword(s):  
Measurement Method ◽  
Water Volume ◽  
Critical Threshold ◽  
Ultrasonic Speed ◽  
Air Bubble ◽  
Clinical Complications ◽  
Speed Measurement ◽  
Ultra Filtration ◽  
Concentration Changes ◽  
Hemodialysis Machine

Fast reduction of blood water volume due to ultra-filtration via hemodialysis machine and critical threshold of blood water volume can result in clinical complications such as hypotension. When blood water volume reduces during hemodialysis process, the concentration of blood forming elements will increase. One of the methods for the monitoring of the concentration changes is ultrasonic speed measurement.In this paper, we optimize the ultrasonic speed measurement method in such a way that it would be compatible with conventional air detector in a hemodialysis machine. Air bubble detecting and the relative blood water volume estimating can be achieved by adding the “sing-around” ultrasonic speed measurement method to the current hemodialysis machine; air bubble detection is achieved by monitoring the decline in the ultrasonic wave amplitude (because of air bubbles) and the protein concentration measurement is achieved by measuring the transit time of the wave. Therefore, the optimized method can be applied to the air detection device of a hemodialysis machine.

scholarly journals Use of Time-of-Flight Ultrasound to Measure Wave Speed in Poplar Seedlings

Forests ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 682 ◽  
Author(s):  
Fenglu Liu ◽  
Pengfei Xu ◽  
Houjiang Zhang ◽  
Cheng Guan ◽  
Dan Feng ◽  
...  
Keyword(s):  
Ultrasonic Velocity ◽  
Wood Density ◽  
Microfibril Angle ◽  
Negative Relationship ◽  
Acoustic Resonance ◽  
Ultrasonic Speed ◽  
Root Collar Diameter ◽  
Collar Diameter ◽  
Root Collar ◽  
Poplar Seedlings

In this study, 145 poplar (Populus × euramericana cv.’74/76’) seedlings, a common plantation tree species in China, were selected and their ultrasonic velocities were measured at four timepoints during the first growth year. After that, 60 poplar seedlings were randomly selected and cut down to determine their acoustic velocity, using the acoustic resonance method. The effects of influencing factors such as wood green density, microfibril angle, growth days, and root-collar diameter on acoustic speed in seedlings and the relationship between ultrasonic speed and acoustic resonance speed were investigated and analyzed in this work. The number of specimens used for investigating growth days and root-collar diameter was 145 in both cases, while 60 and two specimens were used for investigating wood density and the microfibril angle, respectively. The results of this study showed that the ultrasonic speed of poplar seedlings significantly and linearly increased with growth days, within 209 growing days. The ultrasonic velocity of poplar seedlings has a high and positive correlation with growth days, and the correlation was 0.99. However, no significant relationship was found between the ultrasonic velocity and root-collar diameter of poplar seedlings. Furthermore, a low and negative relationship was found between wood density and ultrasonic speed (R2 = 0.26). However, ultrasonic velocity significantly decreased with increasing microfibril angle (MFA) in two seedlings, and thus MFA may have an impact on ultrasonic speed in poplar seedlings. In addition, ultrasonic velocity was found to have a strong correlation with acoustic resonance velocity (R2 = 0.81) and a good correlation, R2 = 0.75, was also found between the dynamic moduli of elasticity from ultrasonic and acoustic resonance tests. The results of this study indicate that the ultrasonic technique can possibly be used to measure the ultrasound speed of young seedlings, and thus early screen seedlings for their stiffness properties in the future.

scholarly journals Ultrasonic Speed and Related Acoustical Parameters of 1,1ʼ-Binaphthalene-2,2ʼ-diyl Diacetate Solutions at 308.15 K

2011 ◽  
Vol 8 (2) ◽  
pp. 762-766
Author(s):  
Pooja P. Adroja ◽  
S. P. Gami ◽  
J. P. Patel ◽  
P. H. Parsania
Keyword(s):  
Adiabatic Compressibility ◽  
Linear Increase ◽  
Solvation Number ◽  
Ultrasonic Speed ◽  
Excellent Correlation ◽  
Acoustical Parameters ◽  
Free Energy Of Activation ◽  
Solvent Systems ◽  
Alcohol Ethyl ◽  
Nonlinear Increase

The density (ρ), viscosity (η) and ultrasonic speed (U) (2 MHz) of chloroform, THF, ethyl alcohol, ethyl acetate, 1,4-dioxane and 1,1ʼ-binaphthalene-2,2ʼ-diyl diacetate (DBNA) solutions have been determined at 308.15 K. Various acoustical parameters namely specific acoustical impedance (Z), adiabatic compressibility (κa), Van der Waals constant (b), intermolecular path length (Lf), internal pressure (π), Raoʼs molar sound function (R), relaxation time (τ), classical absorption coefficient (α/f2)cland solvation number (Sn) have been derived from ρ, η and U data and correlated with concentration (C). A fairly good to excellent correlation has been observed between a particular parameter and C. Linear increase of Z, R, b, (α/f2)cland τ (except EA) (R2= 0.90 – 0.999) and linear decrease of κs, π and Lf(R2= 0.947 – 0.995) with C supported existence of powerful molecular interactions in the solutions and further supported by nonlinear increase of Snwith C. A fairly constant Gibbs free energy of activation has been observed in all the solvent systems studied.

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