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
Twenty sand samples were collected from the sand dunes of Missan fields, Southeastern Iraq. Grain size distribution, mineralogical and chemical composition were studied for the total, medium, and fine-size sand fractions. The grain size analysis shows that the sand is the main component, followed by silt and trace of clay. The predominant grain size of sand is 0.250 to 0.500 mm, which forms more than 57.28 %, which indicates that these dunes were formed under the influence of relatively strong winds and the sedimentary material is close to the source. The light components are quartz, feldspar, and different rock fragments, while the heavy mineral assemblages are composed of opaque minerals, chlorite, mica, and amphiboles.
... Show MoreA study is made about the size and dynamic activity of sunspot using automatically detecting Matlab code ''mySS .m'' written for this purpose which mainly finds a good estimate about Sunspot diameter (in km). Theory of the Sunspot size has been described using equations, where the growth and decay phases and the area of Sunspot could be calculated. Two types of images, namely H-alpha and HMI magnetograms, have been implemented. The results are divided into four main parts. The first part is sunspot size automatic detection by the Matlab program. The second part is numerical calculations of Sunspot growth and decay phases. The third part is the calculation of Sunspot area. The final part is to explain the Sunspot activit
... Show MoreFive oil sample of Mashrif and Nahr Umr Formation for Amarah oil field,
southern Iraq, were taken and analyzed in Geo Mark laboratory in USA center in
order to determine the bulk properties of crude oils and carbon isotopes for these
samples in addition to determine biomarker parameters using Gas
Chromatography(GC), and Gas Chromatography Mass Spectrometry )GCMS
(analytical technique. According to these biomarker analyses of the two formation, it
is indicated that they are non-degraded, marine, non-waxy, derived from
carbonate source and deposition in anoxic marine environment. This study also
showed that the bulk properties (terpanes and steranes) of Amarah oil field are one
family, and the source rocks contai
In our research, several different Statics solutions have been implemented in the processing of seismic data in the south of Iraq for (2D) line seismic survey (AK18) of Abu-khama project with length 32.4 Km and their corresponding results have been compared in order to find optimum static solutions. The static solutions based on the tomographic-principle or combining the low frequency components of field statics with high frequency ones of refraction statics can provide a reasonable static solution for seismic data in the south of Iraq. The quality of data was bad and unclear in the seismic signal, but after applying field statics there is an enhancement of data quality. The Residual static correction improved the qualities of seis
... Show MoreIn southern Iraq, the Yamama Formation has been a primary carbonate resource since the Lower Cretaceous era. This study covers Siba Field, which is located in southeastern Iraq. This paper will be devoted to a YC unit of study. The most crucial step in reservoir management is petrophysical characterization. The primary goal of this research is to assess the reservoir features and lithology of the Yamama (YC) Formation in the Siba region. Accessible excellent logs include sonic, density, neutron, gamma-ray, SP, and resistivity readings. The Interactive Petrophysics (IP4.4) program examined and estimated petrophysical features such as clay volume, porosity, and water saturation. The optimum approach was the neutron density and clay vo
... Show MoreThis paper concerns the study of ripples that occur on the windward of Barchan dunes from the dunes field of Najaf governorate, Iraq. These dunes consist mainly of sand sediments with variable sizes, including medium, fine, and very fine sands. Quartz represents the major light mineral in the Najaf Dunes sand. The prevailing wind direction in the study area is NW-SE. The major ripple crest series of every pattern are oriented perpendicular to the NW-SE wind direction, whereas imbricated ripple groups within the troughs of the preexisting ripples are created by the WSW-ENE wind trend. These ripples tend to be formed by shortened ripples that occupy the troughs of the prolonged series. All crests of the ladderback ripples are oriented at r
... Show MoreIn this paper, a simulation of the electrical performance for Pentacene-based top-contact bottom-gate (TCBG) Organic Field-Effect Transistors (OFET) model with Polymethyl methacrylate (PMMA) and silicon nitride (Si3N4) as gate dielectrics was studied. The effects of gate dielectrics thickness on the device performance were investigated. The thickness of the two gate dielectric materials was in the range of 100-200nm to maintain a large current density and stable performance. MATLAB simulation demonstrated for model simulation results in terms of output and transfer characteristics for drain current and the transconductance. The layer thickness of 200nm may result in gate leakage current points to the requirement of optimizing the t
... Show MoreThis paper presents the electrical behavior of the top contact/ bottom gate of an organic field-effect transistor (OFET) utilizing Pentacene as a semiconductor layer with two distinctive gate dielectric materials Polyvinylpyrrolidone (PVP) and Zirconium oxide (ZrO2) were chosen. The influence of the monolayer and bilayer gates insulator on OFET performance was investigated. MATLAB software was used to simulate and determine the electrical characteristics of a device. The output and transfer characteristics were studied for ZrO2, PVP and ZrO2/PVP as an organic gate insulator layer. Both characteristics show a high drain current at the gate dielectric ZrO2/PVP equal to -0.0031A and -0.0015A for output and transfer characteristics respectively
... Show MoreIn this paper we generalize Jacobsons results by proving that any integer in is a square-free integer), belong to . All units of are generated by the fundamental unit having the forms
our generalization build on using the conditions
This leads us to classify the real quadratic fields into the sets Jacobsons results shows that and Sliwa confirm that and are the only real quadratic fields in .
In this paper we generalize Jacobsons results by proving that any integer in is a square-free integer), belong to . All units of are generated by the fundamental unit having the forms
Our generalization build on using the conditions
This leads us to classify the real quadratic fields into the sets Jacobsons results shows that and Sliwa confirm that and are the only real quadratic fields in .