The analytic solution for the unsteady flow of generalized Oldroyd- B fluid on oscillating rectangular duct is studied. In the absence of the frequency of oscillations, we obtain the problem for the flow of generalized Oldroyd- B fluid in a duct of rectangular cross- section moving parallel to its length. The problem is solved by applying the double finite Fourier sine and discrete Laplace transforms. The solutions for the generalized Maxwell fluids and the ordinary Maxwell fluid appear as limiting cases of the solutions obtained here. Finally, the effect of material parameters on the velocity profile spotlighted by means of the graphical illustrations
Moisture damage is one of the most significant troubles that destroy asphaltic pavement and reduces road serviceability. Recently, academics have noticed a trend to utilize fibers to enhance the efficiency of asphalt pavement. This research explores the effect of low-cost ceramic fiber, which has high tensile strength and a very high thermal insulation coefficient, on the asphalt mixture's characteristics by adding three different proportions (0.75%, 1.5%, and 2.25%). The Marshall test and the Tensile Strength Ratio Test (TSR) were utilized to describe the impact of ceramic fiber on the characteristics of Marshall and the moisture susceptibility of the hot mix asphalt mixture. The Field Emission Scanning Electron Microsc
... Show MoreIncreasing world demand for renewable energy resources as wind energy was one of the goals behind research optimization of energy production from wind farms. Wake is one of the important phenomena in this field. This paper focuses on understanding the effect of angle of attack (α) on wake characteristics behind single horizontal axis wind turbines (HAWT). This was done by design three rotors different from each other in value of α used in the rotor design process. Values of α were (4.8˚,9.5˚,19˚). The numerical simulations were conducted using Ansys Workbench 19- Fluent code; the used turbulence model was (k-ω SST). The results showed that best value for extracted wind energy was at α=19˚, spread distance of wak
... Show MoreThe steady state laminar mixed convection and radiation through inclined rectangular duct with an interior circular tube is investigated numerically for a thermally and hydrodynamicaly fully developed flow. The two heat transfer mechanisms of convection and radiation are treated independently and simultaneously. The governing equations which used are continuity, momentum and energy equations. These equations are normalized and solved using the Vorticity-Stream function and the Body Fitted Coordinates (B.F.C) methods. The finite difference approach with the Line Successive Over-Relaxation (LSOR) method is used to obtain all the computational results. The (B.F.C) method is used to generate the grid of the problem. A computer program (Fortran
... Show MoreThe main objective of this study was to evaluate the adsorption efficiency of two adsorbent materials, Iraqi chicken eggshells (ESh) and activated carbon (AC) derived from ESh powder for the removal of a cationic dye (Janus green B; JGD) from aqueous solution. Activated carbon was synthesised from ESh using a simple chemical activation method using phosphoric acid as the activating agent. The physicochemical properties of the adsorbents were characterised by the Brunauer–Emmett–Teller (BET) method, FT-IR spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma optical emission spectroscopy (ICP-OES), and point of zero charge (pHpzc). The results of BET analysis confirmed th
... Show MoreThe main objective of this study was to evaluate the adsorptionefficiency of two adsorbent materials, Iraqi chicken eggshells (ESh)and activated carbon (AC) derived from ESh powder for theremoval of a cationic dye (Janus green B; JGD) from aqueoussolution. Activated carbon was synthesised from ESh usinga simple chemical activation method using phosphoric acid asthe activating agent. The physicochemical properties of the adsor-bents were characterised by the Brunauer–Emmett–Teller (BET)method, FT-IR spectroscopy, scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy (EDS), inductivelycoupled plasma optical emission spectroscopy (ICP-OES), andpoint of zero charge (pHpzc). The results of BET analysis confirmedthat AC has
... Show MoreA method was developed that offers a rapid, simple and accurate technique for the determination of chlorophenols at trace levels in aqueous samples with very limited volumes of organic solvents. These compounds were acetylated, then preliminarily extracted with n-hexane. The enriched chlorophenols were directly analyzed using gas chromatography with an electron-capture detector. The detection limits were in the range of 0.001–0.005 mg/L, except for 2-chlorophenol, which was always above 0.013 mg/L. Relative standard deviation for the spiked water samples ranged from 2.2 to 6.1%, while relative recoveries were in the range of 67.1 to 101.3%.
Strategic leadership is the main source to enable organizations of excellence in light of turbulent environment, it is also the capabilities of organizational renewal organization’s ability to anticipate changes that take place or possible occurrence.
As a result of the many changes that characterize the environment where they operate researched hospitals, many of them began looking for ways to help it achieve a lot of their own competitive advantages.
The subject of organizational renewal capabilities of subjects that are not obvious interest in the Arab environment in general and Iraq in particular, and longer. The problem of the research and field presence of deficiencies in
... Show MoreBackground: Rheumatoid arthritis is a chronic inflammatory autoimmune disease characterized by joint inflammation, involvement of exocrine salivary and lacrimal glands may occur as extra-articular mani¬festations in this disease. This study aimed to provide evidence of altered in function and composition of salivary gland in patients with rheumatoid arthritis by determine salivary flow rate and some biochemical parameters(total protein, amylase, peroxidase) and to investigate the relationship between disease activity and changes in function and composition of salivary gland. Materials and Methods: Fifty five patients with RA (7 males and 48 females) were enrolled in this study with age range (20-69) years. The patients were separated int
... Show MoreThe gastrointestinal system is one of the many organs in the body that have been affected by the new viral illness known as coronavirus disease 2019 (COVID-19). To find out the GIT symptoms are into patients with Covid-19 and how they correspond with the severity of the illness. At the Al-Shifaa facility, 172 patients infected with COVID-19 participated in our study. A clinical examination, laboratory tests (CRP, D.Dimer, and serum ferritin), a chest CT scan, and a medical history were performed on each patient. The severity of the illness and other factors were taken into consideration while evaluating the gastrointestinal symptoms. Data collection from 172 patients, 91 patients infected with COVID-19 infection, 91 patients (52.9%) had GIT
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