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In this paper, we report the effect of 1.5MeV proton beam irradiation dose on the structural and electrical properties of TiO2 thin films deposited on n-Si substrates. The formation and transformation of different TiO2 phases in the irradiated thin films were characterized by X-ray diffraction and X-ray photoelectron spectroscopy (XPS). X-ray diffraction measurements revealed that the as grown film was rich in Ti5O9 phase and then converted to mixed phases of TiO2 (rutile and anatase) after exposure with radiation doses up to 5 x 14 cm-2. The XPS results revealed the formation of oxygen vacancy (negative) traps in the exposed TiO2 films, which showed strong dependence on the dose. The C-V measurements showed that proton radiations also damaged the Si substrate and created deep level defects in the substrate, which caused a shift of 0.26±0.01V in the flat band voltage (VFB). I-V measurements showed that the ideality factor increased and the rectification ratio dropped with the increase in the radiation dose. The present study showed the stability of TiO2/Si interface and TiO2 film as an oxide layer against proton radiations. [ABSTRACT FROM AUTHOR]

We have grown carbon nanotubes using Fe and Ni catalyst films deposited by atomic layer deposition. Both metals lead to catalytically active nanoparticles for growing vertically aligned nanotube forests or carbon fibres, depending on the growth conditions and whether the substrate is alumina or silica. The resulting nanotubes have narrow diameter and wall number distributions that are as narrow as those grown from sputtered catalysts. The state of the catalyst is studied by in-situ and ex-situ X-ray photoemission spectroscopy. We demonstrate multi-directional nanotube growth on a porous alumina foam coated with Fe prepared by atomic layer deposition. This deposition technique can be useful for nanotube applications in microelectronics, filter technology, and energy storage. [ABSTRACT FROM AUTHOR]

The relation between morphology and energy level alignment in carbon nanotubes (CNT) is a crucial information for the optimization of applications in nanoelectronics, optics, mechanics and (bio)chemistry. Here we present a study of the relation between the electronic properties and the morphology of single wall CNT (SWCNT), aligned multi wall CNT (MWCNT) and unaligned MWCNT. The CNT were synthesized via catalytic chemical vapor deposition in ultra-high vacuum conditions. Combined ultraviolet photoemission and inverse photoemission (IPES) spectra reveal a high sensitivity to the nanotube morphology. In the case of unaligned SWCNT the distinctive unoccupied Van Hove singularities (vHs) features are observed in the high resolution IPES spectra. Those features are assigned to semiconducting and metallic SWCNT states, according to calculated vHs DOS. The two MWCNT samples are similar in the diameter of the tube (about 15 nm) and present similar filled and empty electronic states, although the measured features in the aligned MWCNT are more defined. Noteworthy, interlayer states are also revealed. Their intensities are directly related to the MWCNT alignment. Focussing and geometrical effects associated to the MWCNT alignment are discussed to account the spectral differences. [ABSTRACT FROM AUTHOR]

In general, failures of the system are due to its complexity. Various sub-components are to be considered for the statistical analysis of lifetime of the system. The Weibull distribution is very much used lifetime probability distributions in reliability engineering. Weibull distribution of two parameters represents a decreasing, increasing and constant failure rate. In this study, Weibull distribution having two parameters is to be used to predict the system reliability. [ABSTRACT FROM AUTHOR]

Details of three-dimensional numerical study on 20 mm gravity grouted and centrally reinforced vertical micropile of 600 mm length in uniform sand bed subjected to pull-out loads of inclinations 0°, 5°, 10°, 15°, 20°, 30°, 45°, 60°, 75° and 90° carried out through ABAQUS are presented in this paper. The results of the model study carried out by the same authors on the same micropile subjected to pull-out loads at the same inclinations were used to calibrate the numerical model as well as to compare the analysis results. Axial and lateral load results of the model study were used to calibrate the numerical model. The calibrated numerical model was used to understand the behaviour of micropile at various inclinations of pull-out load. The results of experimental and numerical studies were compared. A reasonably good agreement was found between the two studies. To simulate the behaviour of soil i.e. sand, Mohr–Coloumb constitutive law was used while linear elastic model was used for modelling of reinforcement bar. Linear elasto-plastic constitutive model was used to define the stress–strain behaviour of grout. Interactions between the grout and sand as well as grout and reinforcement bar were modelled using surface-to-surface contact elements approach based on slave–master concept. The results are shown in terms of load-displacement curves. To gain further insight about the behaviour of micropile, horizontal displacement, bending moment and net lateral soil pressure profiles along the length of micropile were also plotted for different inclinations of pull-out load from the numerical study results. [ABSTRACT FROM PUBLISHER]

Since the first report in 2012, molecular copper complexes have been proposed as efficient electrocatalysts for water oxidation reactions, carried out in alkaline/neutral aqueous media. However, in some cases the copper species have been recognized as precursors of an active copper oxide layer, electrodeposited onto the working electrode. Therefore, the question whether copper catalysis is molecular or not is particularly relevant in the field of water oxidation. In this study, we investigate the electrochemical activity of copper(II) complexes with two tetraaza macrocyclic ligands, distinguishing heterogeneous or homogeneous processes depending on the reaction media. In an alkaline aqueous solution, and upon application of an anodic bias to working electrodes, an active copper oxide layer is observed to electrodeposit at the electrode surface. Conversely, water oxidation in neutral aqueous buffers is not associated to formation of the copper oxide layer, and could be exploited to evaluate and optimize a molecular, homogeneous catalysis. [ABSTRACT FROM AUTHOR]

The present investigation was designed to evaluate the effect of heat stress on serum electrolytes concentration viz. calcium, phosphorus, magnesium, sodium, potassium and chloride. During hot ambience serum sodium and chloride levels were increased significantly (p<0.05) than moderate ambience while serum calcium, phosphorus, magnesium and potassium levels were decreased significantly (p<0.05) than moderate ambience. Thus it could be considered that during heat stress condition goat health status can be improved through electrolytes supplementation. [ABSTRACT FROM AUTHOR]