The research addressed an analytical field investigation of the locality of meander, the factors responsible of the locality of the meander at certain points of the stream other than others, and the role sequence of these factors in the formation process.
The research revealed that the location of forming the meander was associated closely with the scale structural composition of the bank materials from which the first stage of forming the curved stream, for the inhomogeneous or non-identical opposite banks in their scale structural composition saw an activity of differential corrosion, while the homogeneous and identical opposite banks in their scale structural composition saw an identical corrosion activity in its intensity at both banks. The research investigated in field the presence of scale variation of the materials of opposite banks in the location of forming the meander which was not found at the incurved stream banks by taking samples and analyze them in scale. The analysis results showed that the synclinal bank was with high sand ratio which was the reason behind the activity of corrosion process due to its weak cohesion, high permeability, and highroughness creating an environment of frequent turmoil reverse eddy currents. As to its opposite bank which represented the convex bank, the results of the scale analysis showed its soil to be with high content of mud; therefore, it was resistant to the corrosion activity compared to the synclinal bank, being more cohesive and of weak permeability, it was soft, so it did not create a turmoil eddy motional environment of the aquatic currents. While in the incurved stream, the results of the scale analysis showed that the soil of both opposite banks were identical in its volume content; therefore, the activity of the corrosion process was identical at both banks and its high sand ratio resulted in the expansion of the stream and not its fold.
The research revealed that the circularity of the curved stream imposed the presence of the centrifugal force which appeared in the domains of the circular motion, changing the concentration locations of the currents. As it is well-known, the fastest currents in the river are those which locate far away from the bottom and the banks, and are found in the middle of the stream which we really found in the incurved stream, but due to the control of the centrifugal force, we found that the fastest currents were concentrated at the synclinal banks and that the slowest currents were concentrated at the synclinal banks, which explains logically and realistically due to the contrast of the corrosion and sediment activity in the curved river streams and the presence of centrifugal force was responsible of the development of these streams from fold to curve to turn to cut lake.
The research defined the morphology of the curved stream at any stage of the development stages at the presence of three corrosion units that represent the synclinal banks meeting three sedimentary units represent the convex banks, two of which were opposite to each other represent overall the neck of the stream and the stream in its complete shape was represented by the overall of these corners
In this work, pure and Ag-doped nickel oxide (NiO) thin films were deposited on glass substrates with different dopant concentrations (0.1, 0.2, 0.3 and 0.4 wt.%) by pulsed-laser deposition (PLD) technique at room temperature. These films were annealed at temperature of 450 °C. The structural and optical properties of the prepared thin films were studied. It was found that annealing process has lead to increase the transmittance of the deposited films. Also, the transmittance was found to increase with doping concentration of silver in the deposited NiO films. The optical energy gap was decreased from 3.5 to 3.2 eV as the doping concentration was increased to 0.4 %.
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Background: There are several diseases in the body following recovery from COVID-19 infection because this virus operates on human genes in various types of peripheral tissue in the human body. It penetrates host cells via Angiotensin-converting enzyme-2 receptors and may have effects on bone remodeling, leading to osteopenia or osteoporosis, which are characterized by low bone mineral density, resulting in diminished bone strength. Bone Alkaline Phpsphatase is an enzyme released into the bloodstream as a soluble homodimer after being cleaved by a phospholipase and can be utilized as a biomarker of bone development. Objective: This research was designed to investigate the alteration of bone homeostasis balance in Iraqi post-COVID-19
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Eco-friendly concrete is produced using the waste of many industries. It reduces the fears concerning energy utilization, raw materials, and mass-produced cost of common concrete. Several stress-strain models documented in the literature can be utilized to estimate the ultimate strength of concrete components reinforced with fibers. Unfortunately, there is a lack of data on how non-metallic fibers, such as polypropylene (PP), affect the properties of concrete, especially eco-friendly concrete. This study presents a novel approach to modeling the stress-strain behavior of eco-friendly polypropylene fiber-reinforced concrete (PFRC) using meta-heuristic particle swarm optimization (PSO) employing 26 PFRC various mixtures. The cement was partia
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Cr2O3 thin films have been prepared by spray pyrolysis on a glass substrate. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of dielectric constant and optical conductivity were expected. It was found that all these parameters increase as the annealing temperature increased to 550°C.
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This study was undertaken to diagnose routine settling problems within a third-party oil and gas companies’ Mono-Ethylene Glycol (MEG) regeneration system. Two primary issues were identified including; a) low particle size (<40 μm) resulting in poor settlement within high viscosity MEG solution and b) exposure to hydrocarbon condensate causing modification of particle surface properties through oil-wetting of the particle surface. Analysis of oil-wetted quartz and iron carbonate (FeCO₃) settlement behavior found a greater tendency to remain suspended in the solution and be removed in the rich MEG effluent stream or to strongly float and accumulate at the liquid-vapor interface in comparison to naturally water-wetted particles. As su
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This article presents the results of an experimental investigation of using carbon fiber–reinforced polymer sheets to enhance the behavior of reinforced concrete deep beams with large web openings in shear spans. A set of 18 specimens were fabricated and tested up to a failure to evaluate the structural performance in terms of cracking, deformation, and load-carrying capacity. All tested specimens were with 1500-mm length, 500-mm cross-sectional deep, and 150-mm wide. Parameters that studied were opening size, opening location, and the strengthening factor. Two deep beams were implemented as control specimens without opening and without strengthening. Eight deep beams were fabricated with openings but without strengthening, while
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