Deep centers and dislocation densities in undoped n GaN, grown by hydride vapor phase epitaxy (HVPE), were characterized as a function of the layer thickness by deep level transient spectroscopy and transmission electron microscopy, respectively. As the layer thickness decreases, the variety and concentration of deep centers increase, in conjunction with the increase of dislocation density. Bas...

Many fluids of hydrocarbon derivatives were used as working fluids in refrigeration and air conditioning during the past few decades. The phase out of chlorofluorocarbons and hydrochlorofluorocarbons has initiated research on finding an alternative working fluid for the existing. In this article, some working fluids with zero ozone depletion potential have been assessed for their suitability as...

Simulation of turbulence boiling, generation of vapour and predication of its behaviour are still subject to debate in the two-phase flow area and they receive a high level of worldwide attention. In this study, a new arrangement of the three dimensional governing equations for turbulence two-phase flow with heat and mass transfer are derived by using ensemble averaging two-fluid model and ...

Properties of selective-area-grown (SAG) ternary and quaternary layers of InGaAs and InGaAsP produced by metal organic vapor phase epitaxy (MOVPE) have been investigated by using a combination of micro-photoluminescence and synchrotron-based micro-beam X-ray fluorescence techniques. Significant variations of the group-III element composition with increase of the oxide mask width and with decrea...

In this study PbTiO 3 thin films were deposited using metalorganic vapor phase epitaxy (MOVPE). Titanium-isopropoxide and tetraethyl-lead were used as the Ti and Pb precursors, and 0 2 was the oxidizing gas. A wide range of conditions for preparing high quality PbTiO 3 thin film were investigated. The epitaxial PbTiO 3 thin films were grown on (001) SrTiO 3 substrates at a growth temperature of...

Advances in automation have facilitated the widespread adoption of high-throughput vapour-diffusion methods for initial crystallization screening. However, for many proteins, screening thousands of crystallization conditions fails to yield crystals of sufficient quality for structural characterization. Here, the rates of crystal identification for thaumatin, catalase and myoglobin using microfl...

By means of electrochemical vapour deposition (E VD), it is possible to grow thin (0.5-j pm), dense airconia/yttria layers on porous ceramic substrates. Kinetics of the EVD process, morphology and oxygen permeation properties of the grown layers are investigated. Very thin (0,.5 t-an) layers are grown at relatively low temperatures (700 SOO’C). Water vapour as reactant enhances the surface reac...

We present cathodoluminescence (CL) studies on low energy e-beam irradiated (LEEBI) metal-organic vapor phase epitaxy (MOVPE) grown GaN films. High intensity LEEBI has been reported to reduce the band-edge photoluminescence intensity of MOVPE grown GaN films. Here we observe similar reduction of band-edge CL intensity with increasing LEEBI dose. The irradiation damage is found to be concentrate...