In this paper, A.C conductivity of micro and nano grain size- TiO2 filled epoxy composites is measured. The dielectric material used is epoxy resin, while micro and nano-sized titanium dioxide (TiO2) of grain size (1.5μm, and 50nm) was used as filler at low filler concentrations by weight (3%, and 5%). Additionally the effect of annealing temperature range (293-373)º K and at a frequency range of 102-106 Hz on the A.C conductivity of the various specimens was studied.
The result of real permittivity for micro and nanocomposite show that the real permittivity increases with decreasing frequency at range of 102-106Hz. The micron-filled material has a higher real relative permittivity than the nano-filled this is true at all the temper

 The junction between  polythiophene,  a conducting  polymer formed by  electrochemical polymerization,  and n-type silicon was  studied the temperature and doping dependencies were observed in the junction characteristics. The increase of junction  temperature leads to increase the saturation current, the barrier height, and decrease of the ideality factor for  junction. While the reduction in doping concentration causes a decrease  in the forward current. The results were  explained  according to the conventional  Schottky diode theories. 

Silicon nanowire arrays (SiNWs) are created utilizing the metal-assisted chemical etching method with an Ag metal as a catalyst and different etching time of 15, 30, and 60 minutes using n-Si (100). Physical properties such as structural, surface morphology, and optical properties of the prepared SiNWs are studied. The diameter of prepared SiNWs ranged from 20 to 280 nm, and the reflectance in the visible part of the wavelength spectrum was less than 1% for all prepared samples. The obtained energy gap of prepared SiNWs was around 2 eV, which is higher than the energy gap of bulk silicon. X-ray diffraction (XRD) has diffraction peaks at 68.70^o for all prepared samples. The heterojunction solar cell was fabricated based on the

Background: It is well known that mycotic antigens have an important
role in atopy and the induction of asthma. Now one of the important
subjects is the relation between respiratory bacterial and viral
infections in the inflammatory reactions accompanied with bronchial
asthma viruses Bacteria or their metabolites act as trigger for asthma
or increase it's intensity .
Objectives: To show the relation between asthma and some viral
infections serologically.
Methods: Direct ELISA test was employed to detect lgG specific for
Respiratory Syncytial virus (Rsv) parainfluenza virus type (p13) and
influenza virus in sera of (100) asthmatic patients of two age groups.
(10-17) and(18-50) years old. Serum samples from

There are no single materials which can withstand all the extreme operating conditions in modern technology.  Protection of the metals from hostile environments has therefore become a technical and economic necessity.  

In this work, for enhancing their wear-resistance, boride layers were deposited on the surface of low carbon steel by a pack cementation method at 850 °C for (2, 4, and 6) h using vacuum furnace. The boronizing process was achieved using different concentration of boron source (20, 25, and 30) % wt. into coating mixture to optimize the best conditions which ensure the higher properties with lower time. The coating was characteristic by X ray diffraction (XRD), and it is confirmed t

In this study, the induced splined shaft teeth contact and bending stresses have been investigated numerically using finite element method(Ansys package version 11.0) with changing the most effecting design parameter,(pressure angle, teeth number, fillet radius and normal module), for internal and external splined shaft. Experimental work has been achieved using two dimensional photoelastic techniques to get the contact and bending stresses; the used material is Bakelite sheet type “PSM-4”.
The results of numerical stress analysis indicate that, the increasing of the pressure angle and fillet radius decrease the bending stress and increase the contact stress for both internal and external spline shaft teeth while the increasing of

The biosorption of Pb (II), Cd (II), and Hg (II) from simulated aqueous solutions using baker’s yeast biomass was investigated. Batch type experiments were carried out to find the equilibrium isotherm data for each component (single, binary, and ternary), and the adsorption rate constants. Kinetics pseudo-first and second order rate models applied to the adsorption data to estimate the rate constant for each solute, the results showed that the Cd (II), Pb (II), and Hg (II) uptake process followed the pseudo-second order rate model with (R2) 0.963, 0.979, and 0.960 respectively. The equilibrium isotherm data were fitted with five theoretical models. Langmuir model provides the best fitting for the experimental results with (R2) 0.992, 0

In this study, thermal characteristics of a two-phase closed heat pipe were investigated experimentally and theoretically. A two-phase closed heat pipe (copper container, Fluorocarbon FC-72 (C6F14) working fluid) was fabricated to examine its performance under the effect of input heat flux range of 250–1253 W/m2 , 70% fill charge ratio and various tilt angles. The temperature distribution along the heat pipe, input heat to evaporator section, and output heat from condenser were monitored. A comprehensive mathematical model was developed to investigate the steadystate heat transfer performance of a two-phase closed heat pipe. A steady state analytical model, is presented to determine important parameters on the design of two-phase close

   Ni-Co-Mn-Mg ferrite nanoparticles with the formula (Ni,Co)xMn0.25-xMg0.75Fe2O4 were synthesized in this work by employing the sol-gel auto-combustion process, with nitrates used as the cations source and citric acid (C6H8O7) as the combustion agent. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), and a vibrating sample magnetometer (VSM) were used to characterize the structural, morphological, and magnetic properties of ferrite powders. The XRD measurements showed crystallite sizes ranging between 24 - 28 nm. The FE-SEM images show the presence of agglomeration as well as a non-homogeneous distribution of the samples. On the other hand, the stoichiometry of the react