OBJECTIVES Micromechanical retention of resin cements to alloys is an important factor affecting the longevity of metal base restorations. This study aimed to compare the bond strength and etching pattern of a newly introduced experimental etchant gel namely Nano Met Etch with those of conventional surface treatment techniques for nickel-chrome (Ni-Cr) and high noble alloys. MATERIALS AND MET...

Due to the use of welded finned tubes in heat exchangers, gas blocks are characterized by very good electric energy production performance, and their reliability can reach 98%. Finned used exchangers usually welded. Such should be characterised following properties: high thermal resistance high-temperature corrosion a flue atmosphere, appropriate joint strength hardness. The most popular techno...

background and aims. substituting chlorhexidine (chx) for water has been shown to enhance antimicrobial activity of mineral trioxide aggregate (mta). the purpose of this study was to compare the compressive strength of mta mixed with distilled water, 0.12% and 0.2% chlorhexidine. materials and methods. mta was mixed according to manufacturer’s instructions in group i (n = 20). in groups ii & ii...

Introduction: Local gradients enable increased gradient strength and faster slew rates, which are both highly desirable to enable high-resolution and fast, real-time imaging(1). The planar gradient set presented in (2) illustrates one such gradient system, where all three gradient axes are incorporated into a uni-planar gradient set that is positioned within the magnet bore. Planar gradients pr...

Piles used in bridges, structures and marine environments are typically produced using concrete, steel, and timber. High repair and replacement costs of these piles have led North American highway agencies and port authorities to investigate the feasibility of using durable materials such as fiber-reinforced polymers (FRP) in pile applications. This paper presents a new generation of composite ...

The electronic properties of carbon nanotubes (NTs) in a uniform transverse field are investigated within a single orbital tight-binding (TB) model. For doped nanotubes, the dielectric function is found to depend not only on symmetry of the tube, but also on radius and Fermi level position. Band gap opening/closing is predicted for zigzag tubes, while it is found that armchair tubes always rema...