Naturally occurring radioactive materials (NORM) contaminated sites at Al-Rumaila Iraqi oil fields have been characterized as a part of soil remediation project. Activity of radium isotopes in contaminated soil have been determined using gamma spectrometer High Purity Germanium detector (HPGe) and found to be very high for Al-Markezia, Al-Qurainat degassing stations and storage area at Khadhir Almay region. The activity concentration of samples ranges from 6474.11±563.8 Bq/kg to 1232.5±60.9 Bq/kg with mean value of 3853.3 Bq/kg for 226Ra, 843.59±8.39 Bq/kg to 302.2±9.2 Bq/kg with mean value of 572.9 Bq/kg for 232Th and 294.31±18.56 Bq/kg to 156.64±18.1 Bq/kg with mean value of 225.5 for 40K. Six hazard indexs radium equivalent, representative level index, adsorbed dose rate in air, annual effective dose equivalent, external hazard index, and internal hazard indexes were calculated to estimate the potential radiological health risk in soil and dose rate associated with it and found to be high. Screening of contaminated soil was performed to evaluate the feasibility of particle size separation. The fractions obtained varied between 75 µm (200 mesh) to 300µm (48 mesh).The results show that the largest weight percent in fine particle size cut ( -75, -125+75, -250+125) µm is 73.9% and all radium isotopes are concentrated in 37.5µm particle size while small fluctuations are observed in the other particle size cuts.
The physical, the thermal and the mechanical properties of Nano-composites, that consisted of Polyprime EP epoxy that reinforced by multi-walled carbon nanotubes (MWCNTs), have been studied. Various loading ratios, 0.1, 0.5, and 1 wt. %of MWCNT shave been infused into epoxy by a magnetic stirrer and then the hardener mixed with the mthat supplied with the epoxy. All sample shave been cutting using CNC machine. Tensile test, three-point bending, hardness tests, lee's disk, differential scanning calorimetry, water absorption and dielectric and electrical conductivity test were utilized on unfilled, MWCNT-filled epoxy to identify the loading effect on the properties of materials. Scanning electron microscopy (SEM) was used to determine the
... Show MoreBackground: Dental stone casts come into contact with impression materials and becomes susceptible to cross contamination from saliva and blood. This study was done to evaluate the physical and mechanical properties of dental stone type IV after treatments with various disinfecting agents and regimes (methods). Materials and Methods: Type IV dental stone and different types of disinfecting agents were used and divided into seven groups: G1: dental stone without disinfection (control group), G2: dental stone mixed with silver nitrate powder 0.5% , G3: dental stone mixed with silver nitrate powder 1%, G4: dental stone mixed with copper sulfate powder 0.5%, G5: dental stone mixed with copper sulfate powder 1% ,G6: dental stone immersed in prop
... Show MoreIn this paper a thin films of selenium was prepare on substrates of n-Si by evaporation in a vacuum technique with thickness about 0.5μm. And then an annealing process was done on samples at two temperature (100 and 200) C ° in a vacuum furnace (10-3 torr).
Some structural, optical and mechanical properties of prepared thin films were measured. Results showed that the prepared film was the crystallization, optical transmittance and micro hardness of the prepared thin films increased significantly after annealing.
In this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J
... Show MoreThe electrospun nanofibers membranes (ENMs) have gained great attention due to their superior performance. However, the low mechanical strength of ENMs, such as the rigidity and low strength, limits their applications in many aspects which need adequate strength, such as water filtration. This work investigates the impact of electrospinning parameters on the properties of ENMs fabricated from polyacrylonitrile (PAN) solved in N, N-Dimethylformamide (DMF). The studied electrospinning parameters were polymer concentration, solution flow rate, collector rotating speed, and the distance between the needle and collector. The fabricated ENMs were characterized using scanning electron microscopy (SEM) to understand the surface morphology and es
... Show MoreThis work investigates the properties of polyvinyl alcohol (PVA) nanocomposite films with varying multi-walled carbon nanotube (MWCNT) content, ranging from 2 to 8 wt.%. The films were prepared using a solution casting method and characterized using UV-visible spectroscopy, optical microscopy, X-ray diffraction, and tensile tests. The prepared PVA/MWCNT nanocomposite films exhibited optical band gap values ranging from 3.5 eV to 5.3 eV. XRD analysis confirmed the semi-crystalline nature of these nanocomposites. Mechanical properties, including hardness, yield strength, ultimate tensile strength, and Young's modulus, were enhanced by increasing MWCNT content by up to 8%. Contact angle measurements showed an increase in hydrophobicity with in
... Show MoreThis paper proposes a novel method for generating True Random Numbers (TRNs) using electromechanical switches. The proposed generator is implemented using an FPGA board. The system utilizes the phenomenon of electromechanical switch bounce to produce a randomly fluctuated signal that is used to trigger a counter to generate a binary random number. Compared to other true random number generation methods, the proposed approach features a high degree of randomness using a simple circuit that can be easily built using off-the-shelf components. The proposed system is implemented using a commercial relay circuit connected to an FPGA board that is used to process and record the generated random sequences. Applying statistical testing on the exp
... Show More120 samples were collected from children (ages between new born and 10 years) who infected with oral thrush. The results revealed that the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) of extracted oil of lemon grass against C.albicans, C.tropicalis, C.keyfr, C.glabrata and C.guilliermondii were 1.25,1.25,1.25,2.5 and 2.5µl/ml and 2.5, 2.5, 2.5, 5 and 5 µl /ml respectively. while the (MIC) and (MFC) for the extraction oil of thyme against C.albicans, C.tropicalis, C.keyfr, C.glabrata and C.guilliermondii were 0.6, 0.6, 1.25, 1.25, and 1.25µl/ml and 1.25, 1.25, 2.5, 2.5, and 2.5µl/ml respectively . While the value of (MIC) and (MFC) for Nystatin against Candida species were 32 and 64 µg
... Show MoreThis work studies developing ultrafiltration (UF) membranes using organic and inorganic additives to remove organic dyes at UF conditions with high effectiveness. Flat sheet (18 wt%) polyvinylidene fluoride (PVDF) membranes were prepared via phase inversion and then developed by adding 6 wt% polyethylene glycol (PEG) as a pore former. Furthermore, the PVDF/PEG membranes were developed by embedding tin oxide nanoparticles (SnO2 NPs) with different contents of 0.3, 0.6, and 0.9 wt%. The prepared membranes were examined for their performance in the dye removal before being characterized using the field emission scanning electron microscope, atomic force microscopy, contact angle, Fourier-transform infrared spectroscopy, surface charge,
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