The effects of temperature,radiation, and illumination on current–voltage characteristics of Au/PVA(Co,Zn-doped)/n-Si Schottky diodes

Polyvinyl alcohol (PVA)/(Co-Ni) nanofiber film was fabricated on silicon wafer using electrospinning technique. The topography of the produced PVA/(Co-Ni) nanofiber film was examined by scanning electron microscopy (SEM). The Au/Poly (vinyl alcohol) (Co, Ni-doped)/n-Si Schottky diode (SD) was thermally formed in evaporating system after the spinning process. At first, the current–voltage (I–V) characteristics of Au/PVA (Co, Zn-doped)/n-Si SD was measured at the room temperature (300 K). For the investigating the effect of temperature, illumination and radiation on Au/PVA (Co, Zn-doped)/n-Si SD comparatively, the measurement was performed under the illumination intensity of 200 W, at 380K, and finally the radiation dose of 22 kGy respectively. The diode characteristics such as the zero-bias barrier height (ϕ_Bo), ideality factor (n) and series resistance (R_s) were calculated at room temperature and under the condition of high temperature, illumination, and radiation. It was found that these characteristics were affected by the illumination and radiation as well as the temperature. The density of interface states (N_ss) distribution profiles as a function of (E_c - E_ss) extracted from the forward I–V measurements were also affected by illumination and radiation even if just a bit. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Effects of sodium caseinate‐ and milk protein concentrate‐based edible coatings on the postharvest quality of Bing cherries

Bing cherries were coated with sodium caseinate‐ or milk protein concentrate‐based edible coatings. Besides the proteins (100 g kg^?1), the coating formulations also included glycerol (about 300 g kg^?1 protein) and either beeswax or a stearic–palmitic acid blend at a concentration of 0, 100 or 300 g lipid phase kg^?1 of protein. All coatings, especially those containing 300 g kg^?1 stearic–palmitic acid blend, successfully reduced water loss of the fruits. The edible coatings had a beneficial effect on the sensory quality of the cherries, and there were significant (p < 0.05) effects of the coating treatments on soluble solids, titratable acidity and pH. Copyright © 2004 Society of Chemical Industry     

Magnesia stabilized zirconia doped with boron,ceria and gadolinia

In this study, magnesia stabilized zirconia based nanocrystalline ceramics were produced through a polymer precursor route using gadolinium and boron. The powders were characterized during the various steps by structural and morphological techniques (FT-IR, XRD, and SEM). XRD results proved that a tetragonal phase is predominant for all samples with varying magnesium contents and no monoclinic zirconia solid solution appears. The crystallite sizes of the samples were calculated using Scherrer equation. The smallest crystallite size was obtained for the sample containing Zr/Mg/Ce/Gd/B ratio of 82/0/10/8/0. The lattice parameters were calculated for cubic, tetragonal, hexagonal, and orthorhombic structures. SEM results show all the samples have spherical grains. The average grain diameters were calculated for all the samples. The smallest average grain diameter was obtained for the sample containing Zr/Mg/Ce/Gd/B ratio of 82/0/10/8/0.     

Preparation and Characterization of PVA/PVP Nanofibers as Promising Materials for Wound Dressing

The PVA/PVP, PVA/PVP with 5% and 10% chitosan and PVA/PVP-Iodine fibers were produced via electrospinning technique. Their morphological and chemical characteristics were examined with SEM, TGA, FT-IR, viscometer and four-point probe conductivity measurement apparatus. The addition of chitosan increased the viscosity and the electrical conductivity of the polymer. The increase chitosan contents resulted in the diameters of the fibers smaller than expected. This was attributed to the increase in the viscosity of the solution and the electrical conductivity of the resulting fibers. The DSC results show that iodine was efficiently cross-linked with the polymer, forming an amorphous structure.     

The role of coal in energy production—Consumption and sustainable development of Turkey

Energy is one of the indispensable factors regarding the assurance of social prosperity and economic development of a country. The developing countries struggle to obtain energy sources reliable in the long term to complete their economic development, and the developed countries struggle to get them to keep their present prosperity levels. Coal seems to continue its indispensable position among the other energy sources for many years because of its production in more than 50 countries, the least effect it has from the price fluctuation and its usage lifespan of more than 200 years. The countries that are aware of it have investments in mining fields in the countries rich in coal reserves, and they continue investing considerable amount of money.     

Dynamic analysis of a trickle bed reactor by moment technique

The performance of a trickle bed reactor is investigated by the moment technique. Residence time distributions of SO₂ tracer in both gas (Helium) and liquid (distilled water) effluents are used to predict zero reduced and first absolute moments and these values are compared with the derived theoretical expressions. Correlations are suggested for gas-liquid mass transfer coefficient, liquid hold up, and extent of axial mixing in liquid phase.True adsorption equilibrium constant of the system is estimated as 0.378 from liquid full bed experiments and contacting efficiency of the trickle bed reactor is found as 0.987.Effect of axial dispersion is not significant on gas-liquid mass transfer coefficient since absorption factor is small, but is found to be quite important on the true estimation of adsorption factor.     

Al-V-graphite interface reactions: an XAFS study of the reactions in a composite interface system

The high temperature reaction properties of a metal matrix composite interface have been observed in this research by X-ray reflectivity and X-ray absorption fine structure (XAFS) coupled to Auger electron spectroscopy (AES). This study was taken from the vantage point of the vanadium diffusion barrier interfacial layer in a model aluminum-graphite metal-matrix laminate composite. The interfacial couple of aluminum and vanadium was analysed to ascertain the reaction species at temperatures between 200 and 350 °C. X-ray reflectivity and glancing angle XAFS showed that the initial Al-V reaction occurred at 325 °C where the aluminum-rich intermetallic Al₃V formed. Small angle XAFS was used to analyse the higher temperature interfacial changes in the temperature range of 300–500 °C. Further interactions occurred at 500 °C, where interdiffusion of Al, C and O occurred leading to phase formation of the vanadium, dependent on the graphite basal plane orientation. AES, used to determine the initial compositions and those resulting from the high temperature heat treatments, complemented the XAFS results.