The hydraulic conditions of a flow previously proved to be changed when placing large-scale geometric roughness elements on the bed of an open channel. These elements impose more resistance to the flow. The geometry of the roughness elements, the numbers used, and the configuration are parameters that can affect the hydraulic flow characteristics. The target is to use inclined block elements to control the salt wedge propagation pointed in most estuaries to prevent its negative effects. The Computational Fluid Dynamics CFD Software was used to simulate the two-phase flow in an estuary model. In this model, the used block elements are 2 cm by 3 cm cross-sections with an inclined face in the flow direction, with a length of their sides 2 and 3 cm. These elements were placed with a constant spacing in two rows at a distance from two sides of the bed of the channel model. Six simulation runs were conducted with two different discharges and three different inclinations of the centerline of the element concerning the flow direction. The applied discharges are 30 and 45.3 l/min, and the inclination of roughness elements are 15o, 30o, and 45o. The spacing between elements in each row is kept at 3cm. The results showed that when no roughness elements were used, the propagation of the salt wedge extended to 3.9m and 3.1m at a discharge of 30 l/min and 45.31/min, respectively. The propagation of the salt wedge was reduced when using the inclined blocks roughness element. This reduction depends on the applied discharge and the angle of inclination. At the minimum applied discharge of 30 l/min, the propagation of the salt wedge was reduced by 74% at 45o inclination. In contrast, it was 69% at 30o and 64% at 15o inclination at the same discharge. When the discharge is 45.3 l/min, the propagation of the salt wedge was reduced by 85% at 45o inclinations of roughness, 84% at 30o. It was 70% at 15o inclinations. The roughness elements improve the flow turbulence that disperses and slows the salt wedge propagation beneath the fresh water.
Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; such methods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasive action. This study was done to assess the effect of three polishing systems on surface texture of new anterior composites after storage in artificial saliva. Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and 3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for one month and then samples were divided into four groups according to surface treatment: Group A (control group):10 specimens received no surfa
... Show MorePoverty phenomenon is very substantial topic that determines the future of societies and governments and the way that they deals with education, health and economy. Sometimes poverty takes multidimensional trends through education and health. The research aims at studying multidimensional poverty in Iraq by using panelized regression methods, to analyze Big Data sets from demographical surveys collected by the Central Statistical Organization in Iraq. We choose classical penalized regression method represented by The Ridge Regression, Moreover; we choose another penalized method which is the Smooth Integration of Counting and Absolute Deviation (SICA) to analyze Big Data sets related to the different poverty forms in Iraq. Euclidian Distanc
... Show More
The present work reports the performance of three types of polyethersulfone (PES) membrane in the removal of highly polluting and toxic lead Pb2+ and cadmium Cd2+ ions from a single salt. This study investigated the effect of operating variables, including pH, types of PES membrane, and feed concentration, on the separation process. The transport parameters and mass transfer coefficient (k) of the membranes were estimated using the combined film theory-solution-diffusion (CFSD), combined film theory-Spiegler-Kedem (CFSK), and combined film theory-finely-porous (CFFP) membrane transport models. Various parameters were used to estimate the enrichment factors, concentration polarization modulus, and Péclet number. The pH values signif
... Show MoreConvection heat transfer in a horizontal channel provided with metal foam blocks of two numbers of pores per unit of length (10 and 40 PPI) and partially heated at a constant heat flux is experimentally investigated with air as the working fluid. A series of experiments have been carried out under steady state condition. The experimental investigations cover the Reynolds number range from 638 to 2168, heat fluxes varied from 453 to 4462 W/m2, and Darcy number 1.77x10-5, 3.95x10-6. The measured data were collected and analyzed. Results show that the wall temperatures at each heated section are affected by the imposed heat flux variation, Darcy number, and Reynolds number variation. The var
... Show MoreMefenamic acid (MA) is one of the non-steroidal anti-inflammatory drugs, it is widely used probably due to having both anti-inflammatory and analgesic activity, the main side effects of mefenamic acid include gastrointestinal tract (GIT) disturbance mainly diarrhea, peptic ulceration, and gastric bleeding. The analgesic effects of NSAIDs are probably linked to COX-2 inhibition, while COX-1 inhibition is the major cause of this classic adverse effects. Introduction of thiazolidinone may lead to the increase in the bulkiness leads to the preferential inhibition of COX-2 rather than COX-1 enzyme. The study aimed to synthesize derivatives of mefenamic acid with more potency and to decrease the drug's potential side effects, new series of 4-t
... Show MoreA simple, accurate and rapid method for separation and determination of most commonly usedinsecticides in Iraq [thiamethoxam (Thi), imidacloprid (Imi), indoxacarb (Ind), and abamectin (Aba)] ispresented. The separation was performed by gradient reversed-phase high performance liquidchromatography on a C18 stationary phase column. The method was developed and validated. The-1mobile phase was a mixture of acetonitrile and water using gradient flow. The flow rate was 1.0 mL min .The optimum temperature of separation was 25 ºC. The detection was performed at multiple wavelengths.The analysis time was up to 10.5 minutes with retention times of 3.221, 3.854, 6.385, and 9.452 min for-1the studied insecticides. The linearity was in the range of 0.
... Show MoreThe high viscosity of heavy oil is a crucial factor that strongly affects its up-stream recovering, down-stream surface transporting and refining processes. Economical methods for recovering the heavy oil and reducing is very important and related to capital and/or operating cost. This research studies the treatment of Iraqi heavy crude oil, which characterize with high viscosity and low API which makes transportation of heavy crude oil a difficult mission, needs for treatment to reduce viscosity for facilitating transportation and processing. Iraqi heavy crude oil was used Sharqi Baghdad, which obtained from Baghdad east oil fields with API 22.2º.Many kinds of additives were used to reduce the viscosity, experiments were performed o
... Show More