The aim of this study was to examine the effect of different acid etching times on the surface roughness and flexural strength of a lithium disilicate-based glass ceramic. Ceramic bar-shaped specimens (16 mm x 2 mm x 2 mm) were produced from ceramic blocks. All specimens were polished and sonically cleaned in distilled water. Specimens were randomly divided into 5 groups (n=15). Group A (contro...

This paper presents the fabrication and characterisation of wet and reactive ion etched ridge waveguide InGaAs/InGaAsP/InP lasers with an operating wavelength of 1.5μm. Characterisation results of InGaAs/InGaAsP/InP lasers are given of two etching methods, namely wet chemical etching and reactive ion etching. Relative advantages and disadvantages of these two methods are also discussed comparat...

background: up to today, the most complete risk assessment tool for repetitive movements of upper limbs has been the occupational repetitive actions (ocra) method. the index of the analysis is relatively accurate. several risk factors such as repeated motion, force, body condition, additional effective factors and return period can be useful for future preventive measures. the present study eva...

In order to expand the use of nanoscaled silicon structures we present a new etching method that allows us to shape silicon with sub-10 nm precision. This top-down, CMOS compatible etching scheme allows us to fabricate silicon devices with quantum behavior without relying on difficult lateral lithography. We utilize this novel etching process to create quantum dots, quantum wires, vertical tran...

We report on the etching of graphene devices with a helium ion beam, including in situ electrical measurement during lithography. The etching process can be used to nanostructure and electrically isolate different regions in a graphene device, as demonstrated by etching a channel in a suspended graphene device with etched gaps down to about 10 nm. Graphene devices on silicon dioxide (SiO(2)) su...

In this paper, a general low-cost and substrate-independent chemical etching strategy is demonstrated for the synthesis of ZnO nanotubes array. During the chemical etching, the nanotubes array inherits many features from the preformed nanorods array, such as the diameter, size distribution, and alignment. The preferential etching along c axis and the surfactant protection to the lateral surface...

Silicon nanowire (SiNW) arrays were produced by electroless method on polycrystalline Si substrate, in HF/ AgNO3 solution. Although the monocrystalline silicon wafer is commonly utilized as a perfect substrate, polycrystalline silicon as a low cost substrate was used in this work for photovoltaic applications. In order to study the influence of etching time (which affects the SiNWs length) on d...

The influence of the aluminum nitride (AlN) film texture on the chemical etching in KOH solution was invested. The AlN films with the different texture and crystal quality were prepared by sputtering. It is found that the chemical etching behaviors, including the etch rate, the activation energy, the surface morphology and the anisotropy, are strongly dependent on the film texture. There is a f...

This study evaluated the extent of water penetration through resin-dentin interfaces before and after being sealed with adhesives. Four adhesive resin systems (2 total-etch adhesives and 2 self-etching primer adhesives) were used in this study. Dentin disks were placed in a split-chamber device, and in situ fluid movement across dentin was measured, with and without physiological pressure, duri...