The change in the optical properties for samples of pure PVA and PVA /K2CrO4composite have been studied .The samples were prepared with different percentage (1,3,5,and 7)%wt of K2CrO4 by casting method technique .In this work ,we are study the absorption ,reflectance spectra ,absorption  coefficient, energy gap ,extinction coefficient ,and transmittance spectra as a function of wavelength range (200-800)nm ,Also  real and imaginary part of dielectric constant have been studied in the range of wave length .The results exhibit the optical properties change by the increase of K2CrO4 concentration, and the values of energy gap for indirect transitions decrease by the increase of the concentration of  K2CrO4

The local asphalt concrete fracture properties represented by the fracture energy, J-integral, and stress intensity factor are calculated from the results of the three point bending beam test made for pre notches beams specimens with deformation rate of 1.27 ^mm/min. The results revealed that the stress intensity factor has increased by more than 40% when decreasing the testing temperature 10˚C and increasing the notch depth from 5 to 30^mm. The change of asphalt type and content have a limited effect of less than 6%.

Through this study, the following has been proven, if  is an algebraically paranormal operator acting on separable Hilbert space, then  satisfies the ( ) property and  is also satisfies the ( ) property for all . These results are also achieved for  ( ) property.    In addition, we prove that for a polaroid operator with finite ascent then after the property ( ) holds for  for all.

In the present work, lead silicate glasses have been prepared with
different amount of lead oxide content. Structure properties such as
X-ray diffraction, AFM, and FTIR analyses have been done. The
exceeding of PbO content more than 25wt% revealed a decreasing in
density. The X- ray revealed that the strongest peak related to
Hexagonal silica dioxide and the other crystal phases formed were
related to silica oxide (SiO2) and lead oxide (PbO). Growth and
decayed phases in X-ray have been observed with changing lead
oxide content. Homogeneous surface was obtained using AFM
analyzer with an average diameter around 100 nm. Infrared spectrum
is characterized by the presence of large absorption band between
120

Unsaturated polyester toughened Epoxy was developed. Epoxy resin had toughened by weight fraction of 10, 20, 30, and 40 wt. % unsaturated polyester. FTIR spectroscopy has been used to investigating the intermolecular hydrogen bonding. Unsaturated polyester–epoxy matrices were characterized for their thermal properties. The FTIR test detected a peak shift of the functional groups which can explain cross-linking occurs between the two resins. The crosslinking between epoxy and unsaturated polyester confirmed via the existence of the stretching asymmetrical C-C band and contraction of the  C-O band. The DSC test demonstrated that glass transition temperature value decreases with epoxy strengthening. The specific heat capacity and the

The effect of annealing temperature (Ta) on the electrical properties like ,D.C electrical conductivity (σ DC), activation energy (Ea),A.C conductivity σa.c ,real and imaginary (ε1,ε2) of dielectric constants ,relaxation time (τ) has been measured of ZnS thin films (350 nm) in thickness which were prepared at room temperature (R.T) using thermal evaporation under vacuum . The results showed that σD.C increases while the activation energy values(Ea) decreases with increasing of annealing temperature.(Ta) from 303- 423 K .
The density of charge carriers (nH) and Hall mobility (μH) increases also with increasing of annealing temperature Hall effect measurements showed that ZnS films were n-type converted to p-type at high annealin

Cadmium Oxide thin films were deposited on glass substrate by spray pyrolysis technique at different temperatures (300,350,400, 500)oC. The optical properties of the films were studied in this work. The optical band-gap was determined from absorption spectra, it was found that the optical band-gap was within the range of (2.5-2.56)eV also width of localized states and another optical properties.

High   Alumina   Glasses   "Alumina   Silicate   Glasses"   was prepared by utilizing powder technology technique. The starting materials are wasted soda-lime glass from an industrial site, Iraqi­ Duekhla raw kaolin and small amounts of potassium carbonates.

X-ray Diffraction and FTIR analysis show complete vitreous glasses are obtained. Increasing Alumina content plays an obvious role in improving physical and mechanical properties of the prepared high  alumina  glass.   In  addition,  the   increased  alumina  content enhanced the dielectric constant and reduced dielectric loss. These results may be interpreted as du

Random laser gain media is synthesized with different types of dye at the same concentration (1×10^-3 M) as an active material and silicon dioxide NPs (silica SiO₂) as scatter centers through the Sol-Gel technique. The prepared samples are tested with UV–Vis spectroscopy, Fluorescence Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-ray Diffraction (EDX). The end result demonstrates that doped dyes with silica nanoparticles at a concentration of 0.0016 mol/ml have lower absorbance and higher fluorescence spectra than pure dyes. FESEM scans revealed that the morphology of nanocrystalline silica is clusters of nano-sized spherical particles in the range (25-67) nm. It is con

In the present study, the effect of new cross-section fin geometries on overall thermal/fluid performance had been investigated. The cross-section included the base original geometry of (triangular, square, circular, and elliptical pin fins) by adding exterior extra fins along the sides of the origin fins. The present extra fins include rectangular extra fin of 2 mm (height) and 4 mm (width) and triangular extra fin of 2 mm (base) 4 mm (height). The use of entropy generation minimization method (EGM) allows the combined effect of thermal resistance and pressure drop to be assessed through the simultaneous interaction with the heat sink. A general dimensionless expression for the entropy generation rate is obtained by con