In this study, the surface of the epoxy/Al composite is treated using a dielectric barrier discharge (DBD) plasma in the presence of air. The epoxy composite was prepared by mixing 0.1g and 0.3 g aluminum powder with epoxy resin and its hardener in a ratio of 3:1. The surface epoxy/Al composite as a dielectric barrier layer (DB) is studied at an applied frequency of 8 kHz and at three exposure times 0, 2, and 4 min. The UV degradation process has been studied using UV-Visible spectroscopy, for these polymers. The absorbance intensity in the UV region (200–320 nm) was high. The absorbance level decreased after 2 minutes and increased after 4 min exposure time. Before exposure to plasma, the epoxy/Al composite at 0.1 g Al had an optical band gap of 3.72eV, while it was 3.6 and 3.42 eV after 2, and 4 min exposure time, respectively. For the composite with 0.3 g Al, the optical band gap was 3.6 eV before exposure which decreased to 3.2 and 2.78 eV after exposure to plasma for 2 and 4 min, respectively. This was due to the increase in conductivity for epoxy/Al composite with 0.3 g Al. Also, after treatment, physical changes happened on their surfaces as well as chemical changes which have been test using AFM technique. Three spectra are characterized by the appearance of halos extending in 2θ range from 16˚ to 45˚ for the XRD spectra of the untreated and treated Epoxy/Al composite samples at several exposed time (0, 2, and 4 min).
The specific activity of 29 soil samples collected from Fuel
Fabrication Facility FFF at AL-Tuwaitha site, 20 km south of
Baghdad were determined using HPGe detector in a low background
configuration, it's relative efficiency of 40%, and resolution of 2keV
for the 1332 keV gamma ray emission of 60Co. The range of activity
concentrations of 226Ra, 232Th and 40K were between (12.56-31.96),
(10.2-18.4) and (47.47-402.1) Bq/kg respectively. In order to assess
any radiological hazard to human health, the absorbed gamma dose
rate D in air at 1m above the ground surface was calculated in the
range (18.87 to 36.46) nGy/h; the outdoor annual effective dose
equivalent AEDE was evaluated to vary from 0.0039 to 0.0076
The physical and chemical parameters of Tigris River water in AL- Kut City have been studied. Three stations have been chosen. . The sampling of study was made monthly and for six months from September 2014 until February 2015.The result of turbidity values showed height mean in summer 84 NTU, The decrease of turbidity was one of the positive results to the effect of AL-Kut Dam on the Tigris River after the Dam and on the total suspended solids. The electrical conductivity was 1340 µs/cm in winter that may be due to the existence of the polluted elements. The river water was fresh (0.48‰ semiebrachish) with a good aerated water and the height of the dissolved oxygen mean value has been noticed 13.1mg/L at many times. Over satura
... Show MoreBackground : The kidneys may be injured in abdominal trauma, both blunt & penetrating. Renal trauma may manifest in a dramatic fashion for both the patient and the clinician. Objectives: To evaluate the incidence, management, morbidity &mortality of renal injury in blunt & penetrating abdominal trauma.
Results:The majority o f patients were males (35= 77.8%), the rest were females (10= 22.2%). The average age was 37 years (range= 18-56 years). The most common grades were grade1, grade2 and grade3 (40=88.9%), while 5 patients (11.1%) were grades 4 and 5.The most common associated injuries were liver, spleen, small & large bowels and diaphragm. The mortality was 20% (9 patients). The most common cause of death was multip
Background: Necrotizing fascitis is a progressive, rapidly spreading inflammatory infection located in the deep fascia, with secondary neerosis of the subcutaneous tissues polymicrobial infection is the most common finding in necrotizing fascitis rather than a single caustive organism.
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
... Show MoreThe object of this research is to reveal the neotectonics of Al-Thirthar, Al-Habbaniya, and Al-Razzazah depressions by using remote sensing data. The age of the exposed rocks ranges from Early Miocene to Holocene. The depressions represent the west margin of the Mesopotamia Zone along its boundary with Al-Salman Zone. The lineament map contains three major groups of lineaments. Two of them are trending east-west and northeast-southwest parallel to the transversal fault systems of Iraq territory. The third group is trending northwest-southeast. The lineament groups reveal the tectonic and structural effects to the extension and the shape of the depressions. The intersection of the lineaments divided the area into small fragments which con
... Show MoreDue to the rapid advancement of technology and the technology of things, modern industries start to need a highprecision equipment and surface finishing, so many finishing processes began to develop. One of the modern processes is Magnetic Abrasive Finishing (MAF), which is a high-precision process for internal and external finishing under the influence of a magnetic field of abrasive particles. Boron Carbide (B4C) ceramics was tested by mixing it with iron (Fe) and produced abrasive particles to reduce the intensity of scraping on the surface, reduce the economic cost and achieve a high finishing addition to remove the edges at the same time. The material selected for the samples was mild steel (ASTM E415) under (Quantity of Abrasives, Mac
... Show MoreLinear and nonlinear optical properties of epoxy/ Al2O3 nanocomposites system were studied for epoxy neat and (0.5, 1.5, 3, and 5) % Al2O3 nanocomposites.The band gap of epoxy and its nanocomposites was obtained at these weight ratios. Nonlinear optical properties experiments were performed using Q-switched Nd:YAG laser z-scan system.These experiments were carried out for different parameters: wavelengths (1064 nm and 532 nm), laser intensities (0.530, 0.679, and 0.772) GW/cm2 and weight ratio of Al2O3 nanocomposites. The results showed that the band gaps were decreased with increasing the weight ratio of nanoalumina except at 5wt% and the nonlinear refractive index coefficient is directly proportional to the incident intensities while o
... Show MoreThis search study the effect of particle size of graphite on the mechanical and thermal properties of epoxy composites, where graphite adopted with particle sizes (45,53,75) ?m, respectively, and the percentages by weight (0,1,3,5,7,9)% for each size of this three particle sizes.Mechanical properties represented by the bending (three-point bending) and through which the conclusion is bending stress and modulus of elasticity, thermal properties were either through thermal conductivity tests.The results showed that the ratio(1%) is the maximum value of bending stress at the three particle size and the (45 ?m) is the maximum.Thermal conductivity result show is the maximum value at ratio (1%) of particle size(53 ?m)
This paper proposed several approaches for estimating the optical turbulence of the Earth’s atmosphere and their effect on solar images’ resolution using ground-based telescopes based on von Kárman, Kolmogorov, and modified von Kárman PSDs models. The results showed a strong correlation coefficient for the modified von Kármán model of atmospheric representation. As can be seen in the case where solar adaptive optics have been properly designed, they typically decrease aberration considerably and provide greatly improved imagery.