introduction: the aim of this experimental laboratory study was to evaluate the effect of different mixing and placement techniques on compressive strength (cs) of calcium-enriched mixture (cem) cement. methods and materials: cem powder was mixed with its liquid either by hand mixing or amalgamator mixing. the mixture was loaded to cylindrical acrylic molds with 6.0±0.1 mm height and 4.0±1 mm d...

Ultrasonic wave propagation in prestressed materials has been studied extensively in the last 40 years. Most of this work was concentrated on the effect of stress on the velocities of different types of ultrasonic waves in homogeneaus materials. Actually stresses affect not only wave velocities but also the boundary conditions at the interface. Many practical applications of ultrasonic stress c...

Ultrasonic measurements have been performed for comprehensive microstructural characterisation in 9 % Cr ferritic steels. The variation in grain size, the effect of solution annealing temperature on microstructure developed, the variation in microstructure of the weld joints, the effect of post weld heat treatment and precipitation behaviour during thermal ageing and creep testing have been suc...

a new method for the synthesis of nano zero-valent iron (nzvi) was developed in the present study.ultrasonic waves, as a novel method, were used to synthesize the nanoparticles. the morphologyand surface compositions of the particles were characterized by using fesem, xrd, bet, andparticle size analyzer. the synthesized nanoparticles were then utilized as a fenton-like catalyst todegrade of hyd...

The effect of ultrasonic irradiation on the viability of human normal (foreskin fibroblast and amniotic fluid epithelial) and tumor (breast carcinoma, melanoma, and lung carcinoma) cells lines was studied. Cells were subjected to ultrasonic irradiation with a frequency of 20 kHz and an intensity of 0.33 W/cm2 for variable periods of time. Several parameters were tested to determine the effects ...

An experimental study was carried out to investigate the effect of local ultrasonic forcing on a turbulent boundary layer. The ultrasonic forcing system was constructed by adhering six ultrasonic transducers to a flat plate over which water was flowed. In this system, the ultrasonic waves projected into the water by the transducers caused cavitation, giving rise to an enormous number of tiny ai...

results although the antibacterial effect of 16 ppm aqueous ozone using a manual technique had an insufficient effect, its ultrasonic application technique resulted in complete disinfection in the root canals. conclusions the bactericidal activity of high concentration of aqueous ozone combined with ultrasonic application technique showed efficacy similar to that of 5.25% naocl in root canals. ...

Ultrasonic energy is used for applying severe plastic deformation on metal surfaces. In the present work, the effect of ultrasonic vibration on the formability, microhardness and microstructural proper...

AIMS To assess whether pre-soaking files in an enzymatic cleaner prior to ultrasonic cleaning had any effect on cleanliness and also to assess the effect of the time that endodontic files spend in an ultrasonic bath prior to sterilization on their overall cleanliness. METHODOLOGY Twenty root canals in a total of ten patients were cleaned and shaped using conventional techniques. Following use...