in the present work, the influence of aging temperature on mechanical properties and sound velocity of maraging steel m350 was investigated. for this purpose, first, samples were solution annealed at 825◦c for 2 hours and then age hardened at 510◦c-600◦c for 3 hours. hardness, tensile and impact tests were used for determining mechanical properties and longitudinal ultrasonic velocity was used ...

Apparent molar compressibilities (φk) and apparent molar volume (φv) of L-valine, L-leucine andL-phenylalanine in aqueous solution of KNO3 at different concentrations have been determined at the temperature 303.15K using a standard ultrasonic frequency of 2 MHz. The above parameters can be evaluated from precise density, ultrasonic velocity and time flow measurements using a specific gravity bo...

Acoustic communication has an important role in the reproductive behaviour of anurans. Although males of the concave-eared frog (Odorrana tormota) have shown an ultrasonic communication capacity adapted to the intense, predominately low-frequency ambient noise from local streams, whether the females communicate with ultrasound remains unclear. Here we present evidence that females exhibit no ul...

Ultrasonic flow meters are gaining wide usage in commercial, industrial and medical applications. Major benefits of utilizing this type of flowmeter are higher accuracy, low maintenance (no moving parts), noninvasive flow measurement, and the ability to regularly diagnose health of the meter. This application note is intended as an introduction to ultrasonic time-of-flight (TOF) flow sensing us...

When a new spectrometric method is introduced in the literature, the method is investigated initially with instruments with a number of different designs. Each new application of the spectrometric method requires a set of trial experiments to optimize the instrumental parameters. Eventually the different applications and instrumental designs assist in establishing the fundamental advantages and...

The advent of dry point transducers has allowed new possibilities for ultrasonic testing of concrete structures and rock specimens. Recent developments in the technology such as single and multi-channel ultrasonic pulse echo technology and the automated determination of the modulus of elasticity have been pushing back the boundaries of the method. The effect of this has been to increase the eas...

Among novel structural materials, composites are attractive because they combine the properties of two o more individual components. As an important example, in alumina-zirconia ceramic composite system, the incorporation of α-Al2O3 into stabilized zirconia increases significantly the mechanical and thermal properties. In this work an alumina-zirconia ceramic composite have been prepared with d...

Utilizing a Doppler ultrasonic flowmeter catheter, right carotid artery blood velocity was measured during 91 coughing episodes in 16 patients. Such coughing reduced carotid blood velocity by 40 +/- 22% (control = 34 +/- 8 cm per second, cough = 20 +/- 9 cm per second, p less than 0.001). There was an insignificant low degree of corrleation between the level of simultaneously recorded mean righ...

Acoustic microscopy [1] is used to measure the V(Z) curves and thereby determine the ultrasonic velocities on the surfaces of solid materials. The acoustic transducer, pointor line-focusing, is defocused below the sample surface through the coupling water. The focal depth Z is changed to extract the interference between the specular reflection signal and the leaky surface wave signal(s). Their ...