Many of the proposed methods introduce the perforated fin with the straight direction to improve the thermal performance of the heat sink. The innovative form of the perforated fin (with inclination angles) was considered. Present rectangular pin fins consist of elliptical perforations with two models and two cases. The signum function is used for modeling the opposite and the mutable approach of the heat transfer area. To find the general solution, the degenerate hypergeometric equation was used as a new derivative method and then solved by Kummer's series. Two validation methods (previous work and Ansys 16.0‐Steady State Thermal) are considered. The strong agreement of the validation results (0.31% to 0.52%) lends to the reliability of the presented model. It was found that use of the perforated fin leads to decreased thermal resistance and improvement in the thermal performance of the pin fin by enhancing the heat transfer and increasing Nusselt number. Also, the increase of the inclination angle, size, and number of perforations can be used to optimize the present model by maximizing the heat transfer area and minimizing both the weight and length of the pin fins.
The study's objective is to produce Nano Graphene Oxide (GO) before using it for batch adsorption to remove heavy metals (Cadmium Cd+2, Nickel Ni+2, and Vanadium V+5) ions from industrial wastewater. The temperature effect (20-50) °C and initial concentration effect (100-800) mg L-1 on the adsorption process were studied. A simulation aqueous solution of the ions was used to identify the adsorption isotherms, and after the experimental data was collected, the sorption process was studied kinetically and thermodynamically. The Langmuir, Freundlich, and Temkin isotherm models were used to fit the data. The results showed that Cd, Ni, and V ions on the GO adsorbing surface matched the Langmuir mo
... Show MoreWater flow into unsaturated porous media is governed by the Richards’ partial differential equation expressing the mass conservation and Darcy’s laws. The Richards’ equation may be written in three forms,where the dependent variable is pressure head or moisture content, and the constitutive relationships between water content and pressure head allow for conversion of one form into the other. In the present paper, the “moisture-based" form of Richards’ equation is linearized by applying Kirchhoff’s transformation, which
combines the soil water diffusivity and soil water content. Then the similarity method is used to obtain the analytical solution of wetting front position. This exact solution is obtained by means of Lie’s
Based on collections made during March to September 2012. A totals of 58 species belong to 33 genera were identified from extra north to extra south of Erbil governorate, among them 30 species are registered as a new record to flora of Iraq. Most attention was paid to the most common and abundant lichens that present almost in most locations, which were Collema cristatum, Diploschistes scruposus, Lecanora dispersa, Lecanora murales, Pertusaria flavicunda, Placidium lacinulatum, Thelomma californicum and Verrucaria Maura.
The possibility of using zero-valent iron as permeable reactive barrier in removing lead from a contaminated groundwater was investigated. In the batch tests, the effects of many parameters such as contact time between adsorbate and adsorbent (0-240 min), initial pH of the solution (4-8), sorbent dosage (1-12 g/100 mL), initial metal concentration (50-250 mg/L), and agitation speed
(0-250 rpm) were studied. The results proved that the best values of these parameters achieve the maximum removal efficiency of Pb+2 (=97%) were 2 hr, 5, 5 g/100 mL, 50 mg/L and 200 rpm respectively. The sorption data of Pb+2 ions on the zero-valent iron have been performed well by Langmuir isotherm model in compared with Freundlich model under the studied
The present study aimed to investigated Giardia duodenalis in cattle in some different areas of Wasit province by using molecular study and verification of the genotype of Giardia duodenalis. Collected one hundred fecal samples from cattle, the result showed that the rate of infection was 83% (100) . DNA was extracted from the 100 positive samples from the cattle then amplified using the special tris-phosphatesomerase gene for genotyping A and B. The result of type A infection was (69%) and (45%) of the genotype B. The purpose of this study was to investigate the genotypes of cattle in Wasit province and compare them with previous sources at the NCBI data bank.
The aim of this study is to propose mathematical expressions for estimation of the flexural strength of plain concrete members from ultrasonic pulse velocity (UPV) measurements. More than two hundred pieces of precast concrete kerb units were subjected to a scheduled test program. The tests were divided into two categories; non-destructive ultrasonic and bending or rupture tests. For each precast unit, direct and indirect (surface) ultrasonic pulses were subjected to the concrete media to measure their travel velocities. The results of the tests were monitored in two graphs so that two mathematical relationships can be drawn. Direct pulse velocity versus the flexural strength was given in the first relationship while the second equation des
... Show MoreIn this study, sawdust as a cheap method and abundant raw material was utilized to produce active carbon (SDAC). Physiochemical activation was utilized where potassium hydroxide used as a chemical activating agent and carbon dioxide was used as a physical activating agent. Taguchi method of experimental design was used to find the optimum conditions of SDAC production. The produced SDAC was characterized using SEM to investigate surface morphology and BET to estimate the specific surface area. SDAC was used in aqueous lead ions adsorption. Adsorption process was modeled statistically and represented by an empirical model. The highest specific surface area of SDAC was 688.3 m2/gm. Langmuir and Freundlich isotherms were used to
... Show MoreStudies in Iraq that concerned identification of free-living Protozoa (sarcodina) are scarce; so the current study deals with these protozoan communities inhabiting the Tigris River in Baghdad City. Sampling collection stations have been selected at each of AL-Gheraiˈat and AL-Adhamiyah area adjacent to the river. Monthly intervals sampling with three samples were collected from each station from June to September 2020. Total of 23 sarcodina taxa were listed, out of them 5 taxa were new record to the Tigris River in Baghdad: Difflugia urceolata Carter, 1864 (Arcellinida, Difflugiidae), Heleopera perapetricola Leidy, 1879 (Arcellinida, Heleoperidae), Rhaphidiophrys pallida F.E. Schulze, 1874 (Centrohelida, Raphidiophridae), Saccamoeba sp
... Show MoreThe cuneiform texts considered one of the most important resources which play an important role help us to know how was the economic , politic and religious manner and every thing have relation of the history of Mesopotamia which contain many of information that enrich our knowldgement every side of Mesopotamia civilization since using writing as away to register the science and human knowldgement . The city of Sippar (Abu –Habba ) was one of most important city of ancient Mesopotamia which mentioned as one of first five Mesopotamian cities found before floating and it exposed through excavating rich one of them tablet which some of it dated to old Babylon period . The king Ammi-Saduqa has a big share of tablet we study number of thi
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