on this research is to study the effect of nickel oxide substitution on the pure phases superconductor Tl0.5Pb0.5Ba2Can-1Cun-xNixO2n+3-δ (n=3) where x=(0,0.2,0.4,0.6,0.8.and 1.0). The specimens in this work were prepared with used procedure of solid state reaction with sintering temperature 8500C for 24 h .we used technical (4-prob)to calculated and the critical temperature Tc . The results of the XRD diffraction analysis showed that the structure for pure and doped phases was tetragonal with phases high-Tc phase (1223),(1212) and low-Tc phase (1202) and add to the presence of some impure phase. It was noted the value a=b,c the parameter of the lattice increment with the increment of Ni content. The increment of (NiO) concentration effects electrical resistivity, dielectric constant and the hardness.
The long – term behaviour of polyethylene products used out doors is affected by weathering. In the present work,
weathering test was carried out to find the effect of the environment conditions on the mechanical properties of
HDPE/LLDPE blends with different weight percents (0, 15, 30, and 45 %) relative to the LLDPE by increasing the
exposure times to (100, 150, 200, 250, 300) hr.
A series of tests (destructive), tensile, impact and hardness were carried out on the prepared samples, the results
obtained declare the changes on the material behaviour from ductile to brittle and the polymer shows a decline in the
mechanical properties with increasing the exposure times.
In the present work empirical equations were r
Tensile , thermal, and barrier properties of polylactide PLA-based
nanocomposite films that were prepared by solvent casting method with
polyethylene glycol (PEG), and alumina were studied. PLA/PEG blend showed
decrease in tensile strength and Young modulus but increased in elongation in
PLA/PEG and increased in crystalline of PLA but decrease in glass transition
temperature with the increasing of PEG concentration . A nano blend composites of
PLA/PEG/alumina (50/50/4) when compared to PLA/PEG blend indicated that
tensile strength , Young modulus and glass transition temperature (Tg) increased
with adding alumina nano particles, concentration and barrier properties
improvement due to its nucleating and reinforc
In this study, composite materials were prepared using unsaturated polyester resin as binder with two types of fillers (sawdust and chopped reeds). The molding method is used to prepare sheets of UPE / sawdust composite and UPE / chopped reeds composite. The mechanical properties were studied including flexural strength and Young's modulus for the samples at normal conditions (N.C). The Commercial wood, UPE and its composite samples were immersed in water for about 30 days to find the weight gain (Mt%) of water for the samples, also to find the effect of water on their flexural strength and Young's modulus. The results showed that the samples of UPE / chopped reeds composite gained highest values of flexural strength (24.
... Show MoreVisible-light photodetectors constructed Fe2O3 were manufactured effectively concluded chemical precipitation technique, films deposited on glass substrate and Si wafer below diverse dopant (0,2,4,6)% of Cl, enhancement in intensity with X-ray diffraction analysis was showed through favored orientation along the (110) plane, the optical measurement presented direct allowed with reduced band gap energies thru variation doping ratio , current–voltage characteristics Fe2O3 /p-Si heterojunction revealed respectable correcting performance in dark, amplified by way of intensity of incident light, moreover good photodetector properties with enhancement in responsivity occurred at wavelength between 400 nm and 470 nm.
Recent research has examined the improvement of physical and dielectric properties of BaTiO3 ceramic material by small addition of excess TiO2 or BaCO3. The prepared samples sintered at different temperatures and varying soaking time. The results show that increasing the sintering temperature within 1350°C and soaking time of 10 hrs give better electrical and physical properties, which indicate the reaction is complete at higher temperature and period.
Porous silicon was prepared by using electrochemical etching process. The structure, electrical, and photoelectrical properties had been performed. Scanning Electron Microscope (SEM) observations of porous silicon layers were obtained before and after rapid thermal oxidation process. The rapid thermal oxidation process did not modify the morphology of porous layers. The unique observation was the pore size decreased after oxidation; pore number and shape were conserved. The wall size which separated between pore was increased after oxidation and that effected on charge transport mechanism of PS
This research deals with the effect of gallium oxide and cerium oxide as dopants on the structural and optical characteristics of tin oxide. Gallium and cerium oxide doped tin oxide was prepared with different doping concentrations (0, 0.03, 0.05 and 0.07) wt. pure and doped tin oxide thin films were prepared by the pulsed laser deposition technique. X-ray diffraction and UV-Visible spectrophotometer were employed to investigate both oxides doping effects. Results showed that all prepared samples have poly-crystalline structure with a preferred plane of crystal growth along (110), where the crystal size grew from 40.3 nm to 64.5 nm and to 43.5 nm for Ga2O3 and CeO2 doped tin oxide thin films, res
... Show MoreThe purpose of this work is to determine the points and planes of 3-dimensional projective space PG(3,2) over Galois field GF(q), q=2,3 and 5 by designing a computer program.
The aim of this research is to study the effects of the North Atlantic Oscillation (NAO) on the temperature and precipitation patterns in Baghdad city. Data of the monthly means of the NAO index,the monthlymeans of temperature, and the monthly total of precipitation were analyzed for the period 1900-2008. Non-parametric tests were used to investigate the correlations between these variables. The time series of temperature and precipitation showed no trends. The results indicated that is a slight correlation between the NAO and temperature and precipitation suggesting that NAO has no major effects on the temperature and precipitation patterns in Baghdad city.
In this research various of 2,5-disubstituted 1,3,4-oxadiazole (Schiff base, oxo-thiazolidine , and other compounds) were synthesized from 2,5-di(4,4?- amino-1,3,4-oxadiazole ) which use quently synthesized from mixture of 4-amino benzoic acid and hydrazine in the presence of polyphosphorus acid. The synthesized compounds were characterized by using some Spectral data (UV, FT-IR, and 1H-NMR).