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
Tillage tools are subject to friction and low-stress abrasive wear processes with the potential deterioration of the desired soil quality, loss of mechanical weed efficacy, and downtime for replacing worn tools. Limited experimental methods exist to quantify investigate the effect of wear-resistant coatings on shape parameters of soil-engaging tools. ASTM standard sand/rubber wheel abrasion and pin-on-disk tests are not able to simulate wear characteristics of the complex shape of the tillage tools. Even though the tribology of tillage tools can be realistic from field tests, tillage wear tests under field conditions are expensive and often challenging to generate repeatable engineeri
This study is conducted to determine the effect of pathogenicity of the fungus Lecanicillium lecanii in some aspects of life of the insect saw toothed beetle Oryzaephilus surinamensis L. (Coleoptera: Silvanidae) under laboratory conditions with three concentrations of spores and mildew commentator (1 × 103, 1 × 105, 1 × 107) spore / ml , on eggs and larvae second phase of the insect .The study also includs the effect of the fungus concentrations of germination on rice (jasmine) by using direct spray treatment. The results show great fungus efficiency in the control of some aspects of life of the insect, where varied efficiency depends on the concentration of spores, The highest percentage loss of eggs is 63.33% at a concentration
... Show MoreIn this work, the Whittaker wave functions were used to study the nuclear density distributions and elastic electron scattering charge form factors for proton-rich nuclei and their corresponding stable nuclei (10,8B, 13,9C, 14,12N and 19,17F). The parameters of Whittaker’s basis were fixed to generate the experimental values of available size radii. The Whittaker basis was connected to harmonic-oscillator basis through boundary condition at match point. The nuclear shell model was opted with pure configuration for all studied nuclei to compute aforementioned studied quantities except 10
This work deals with thermal cracking of heavy vacuum gas oil which produced from the top of vacuum distillation unit at Al- DURA refinery, by continuous process. An experimental laboratory plant scale was constructed in laboratories of chemical engineering department, Al-Nahrain University and Baghdad University. The thermal cracking process was carried out at temperature ranges between 460-560oC and atmospheric pressure with liquid hourly space velocity (LHSV) equal to 15hr-1.The liquid product from thermal cracking unit was distilled by atmospheric distillation device according to ASTM D-86 in order to achieve two fractions, below 220oC as a gasoline fraction and above 220oC as light cycle o
... Show MoreThe effect of three ionic liquids viz., 1-hexyl-3-methylimidazolium tetrafluoroborate (ILE), 1-hexyl-3-metylimidazolium hexafluorophosphate (ILF) and 1-octyl-3-methylimidazolium tetrafluoroborate (ILG) when used as surfactants on the performance of dissolved air floatation (DAF) was investigated.
Experiments were conducted at a temperature of 30-35 ºC, 10ppm ferric chloride as coagulant, 50% recycle ratio, pH 8, and 10 minutes treatment time to find oil and grease (OG) and turbidity removal efficiencies at saturation pressure (2-6) bar.
ILs were used at concentration of 50 µl/liter of treated water in two positions in DAF system; the saturation vessel and the treatment tank. The performance using ILs
... Show MoreThis paper is focused on orthogonal function approximation technique FAT-based adaptive backstepping control of a geared DC motor coupled with a rotational mechanical component. It is assumed that all parameters of the actuator are unknown including the torque-current constant (i.e., unknown input coefficient) and hence a control system with three motor control modes is proposed: 1) motor torque control mode, 2) motor current control mode, and 3) motor voltage control mode. The proposed control algorithm is a powerful tool to control a dynamic system with an unknown input coefficient. Each uncertain parameter/term is represented by a linear combination of weighting and orthogonal basis function vectors. Chebyshev polynomial is used
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