A two-dimensional model has been developed to simulate the corrosion of nuclear fuel pellets under permanent waste disposal conditions in a steel vessel with a corrosion-resistant copper shell. The primary emphasis was on the corrosion behavior within cracks with various dimensions. It was shown that a simplified α-radiolysis model which only accounts for the radiolytic production of H2O2 and H...

The ultrasonic infrared thermal wave method is a new nondestructive testing technique. It is remarkably sensitive and convenient for detection of small vertical cracks, such as fatigue cracks in metals. Pulses of ultrasonic launched by the ultrasonic emitter as heat source are excited into the sample, if there are some cracks in the material, they will be revealed through their heat generation,...

OBJECTIVES The objective of this study was to assess the effect of new bonding techniques on enamel surface. MATERIALS AND METHODS Sixty upper central incisors were randomly divided into two equal groups. In the first group, metal brackets were bonded using TransbondXT and, in the second group, the same brackets were bonded with Maxcem Elite. The shear bond strength (SBS) of both agents to en...

Ultrasonic testing for fatigue crack detection in metallic members are commonly performed using time domain analysis of Rayleigh waves. This approach will be successful only if the fatigue cracks produce strong interaction with the Rayleigh waves. The optimum frequency range of ultrasonic Rayleigh waves for scanning long structural members in the field is from 0.5 to 2.25 MHz because higher fre...

– The relation between fracture surface morphology and the three-dimensional structure of crack fronts is investigated through direct observation of brittle cracks in gels. A key notion in this investigation is the discontinuity of the crack front, whose advancement creates the fracture surface. We discuss the significance of our findings in the studies of general three-dimensional brittle frac...

Performance requirements of the patch repair material are strength, size stability, shieldability, durability, bond property with the substrate concrete, ductility and so forth. Various kinds of patch repair materials with short fibers have been developed and used. Engineered Cementitious Composites (ECC) which provides multiple cracking and strain hardening behavior is also one of the attracti...