The impact of information and communication technology (ICT), education and regulation on economic freedom in Islamic Middle Eastern countries

Our study investigated the impact of ICT expansion on economic freedom in the Middle East (Bahrain, Iran, Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi Arabia, Syria, United Arab Emirates, and Yemen). Our empirical analysis used archival data from 1995 to 2005; it showed that ICT expansion in the Middle East has been effective both in bridging the digital divide and also in promoting economic freedom in a region that was vulnerable to political, social, and global conflict. However, differences between countries, such as the educational attainment of their citizens and institutional resistance to technology acceptance, both enhanced and restricted the relationship between ICT and economic freedom.     

Characterization of boron-doped micro- and nanocrystalline diamond films deposited by wafer-scale hot filament chemical vapor deposition for MEMS applications

Micro- and nanocrystalline diamond (MCD and NCD) films are deposited on 4-inch silicon substrates by a large-area multi-wafer-scale hot filament chemical vapor deposition (HFCVD) system. The films are in-situ doped by boron. The chemical and crystalline structures are studied by electron probe microanalysis (EPMA), Raman spectroscopy and X-ray diffraction (XRD). The microcrystalline films have a preferred (111) texture, while the nanocrystalline films exhibit (220) texture. Strain gauges and cantilever beam arrays are micro-fabricated by surface micro-machining techniques to characterize the residual strain and strain gradient of the diamond films. Both micro- and nanocrystalline films have small compressive strains of − 0.052% and − 0.040% respectively, with the strain gradient of about 10^− 5 μm^− 1. These values are low enough to enable the realization of many MEMS devices.     

A facile method to grow V-doped TiO2 hydrophilic layers with nano-sheet morphology

V-doped titania layers with a novel morphology and a rough surface were grown the via micro arc oxidation process in the electrolytes consisting of sodium vanadate under various voltages. Morphological investigations, performed by SEM, revealed that the layers had a sheet-like structure whose average thickness was less than 100 nm depending on the applied voltage. Our XRD and XPS results showed that the layers consisted of anatase, rutile, and vanadia phases with a varying fraction depending on the voltage. Hydrophilicity of the layers was also studied by measuring the water contact angle on their surfaces under ultraviolet and visible illuminations. The layer synthesized under the voltage of 450 V exhibited the highest hydrophilicity.     

In-Situ Reduction of Promoted Cobalt Oxide Supported on Alumina by Environmental Transmission Electron Microscopy

Abstract  

Reduction of 12wt.%Co/0.5wt.%Re/α-Al₂O₃ Fischer–Tropsch catalyst has been studied in-situ in an environmental transmission electron microscope. Reduction of Co₃O₄ to metallic cobalt was observed dynamically at 360 °C under 3.4 mbar H₂. Structural and morphological changes were observed by high resolution transmission electron microscopy and scanning transmission electron microscopy imaging. The cobalt particles were mainly face centred cubic while some hexagonal close packed particles were also found. Reoxidation of the sample upon cooling to room temperature, still under flowing H₂, underlines the reactivity of the nanoparticles and the importance of controlling the gas composition and specimen temperature during this type of experiment. Similar behaviour was observed for a non-promoted catalyst. Imaging and analysis of the promoted sample before and after reduction indicated a uniform distribution of the promoter.     

Electrochemical oxidation of 4-morpholinoaniline in aqueous solutions: Synthesis of a new trimer of 4-morpholinoaniline

Electrochemical oxidation of 4-morpholinoaniline has been studied in various pHs using cyclic voltammetry and controlled-potential coulometry. The electrochemical trimerization of 4-morpholinoaniline is described and its mechanism has been studied in aqueous solution. This method provides a green, reagent-less, and environmentally friendly procedure with high atom economy, for the synthesis of “4-morpholinoaniline-trimer” using a carbon electrode in an undivided cell in good yield and purity.     

Developing chromic dyeable PET nanocomposites: The dye absorption and complex formation mechanisms

This research aimed to investigate the possibility of enhancement of polyethylene terephthalate (PET) dyeability using nanotechnology. Different kinds of disperse, acidic, and chromic dyes were used for dyeing of produced PET/silver nanocomposite fine multifilament yarns produced at the take up speeds of 3000 m min⁻¹ and their prepared fabrics. Dyeability improved by using acidic dyes. However, the more promotion effect was achieved by chromic dyes. No effect on absorption of disperse dyes revealed that no physical effect can be considered for dye absorption. The electrostatic interaction between silver and acidic dye molecules and forming the coordinative bonds with chromic dye molecules on nanocomposite yarns and fabrics were concluded and thoroughly discussed. Applying chromic dye with the more potential of creating coordinative bonds intensified the improvement of dyeability. Optimized silver ratio for the dyeability enhancement was affected by the mechanisms of dye absorptions discussed and proven by investigating dye concentrations in the effluent baths after the dyeing processes. It has been found that the steric hindrance is the key factor for absorption of chromic dyes; however, it is different in the case of acidic dyes, well discussed according to the dye absorptions mechanisms. The results can be also considered as evidence to prove forming the coordinative bonds with chromic dye molecules. This has also been confirmed by appearing a bathochromic shift in the absorption peaks by increasing dyeability using chromic dye. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Structural and electronic properties of C and BN nanotubes based on periodic fullerenes: A density functional theory study

The structural and electronic properties of C and BN nanotubes based on periodic fullerenes were studied using density functional theory. It was shown that these tubular structures are stable. The electronic band structures and density of states indicated that the C nanotubes based on periodic fullerenes are metals. The energy band gap was appeared by substitution of C atoms with B and N atoms. The BN nanotubes based on periodic fullerenes show semiconducting properties. Our results suggest that the nanotubes based on periodic fullerenes can be used to design of nanoelectronic devices.     

Evaluation of Composition-Dependent Collection Efficiencies for the Aerodyne Aerosol Mass Spectrometer using Field Data

In recent years, Aerodyne aerosol mass spectrometers (AMS) have been used in many locations around the world to study the size-resolved, nonrefractory chemical composition of ambient particles. In order to obtain quantitative data, the mass or (number) of particles detected by the AMS relative to the mass (or number) of particles sampled by the AMS, i.e., the AMS collection efficiency (CE) must be known. Previous studies have proposed and used parameterizations of the AMS CE based on the aerosol composition and sampling line relative humidity. Here, we evaluate these parameterizations by comparing AMS mass concentrations with independent measurements of fine particle volume or particle-into-liquid sampler (PILS) ion chromatography measurements for 3 field campaigns with different dominant aerosol mixtures: (1) acidic sulfate particles, (2) aerosol containing a high mass fraction of ammonium nitrate, and (3) aerosol composed of primarily biomass burning emissions. The use of the default CE of 0.5 for all campaigns resulted in 81–90% of the AMS speciated and total mass concentrations comparing well with fine particle volume or PILS measurements within experimental uncertainties, with positive biases compared with a random error curve. By using composition-dependent CE values (sometimes as a function of size) which increased the CE for the above aerosol types, the fraction of data points within the measurement uncertainties increased to more than 92% and the mass concentrations decreased by ～5–15% on an average. The CE did not appear to be significantly dependent on changes in organic mass fraction although it was substantial in the 3 campaigns (47, 30, and 55%).

Copyright 2012 American Association for Aerosol Research