In the present work, the behavior of thick-walled cylinder of elasto-plastic material (polymeric material) has been studied analytically. The study is based on modified Von-Mises yield criterion (for non metallic material). The equations of stress distribution are obtained for the cylinder under general cases of elastic expansion, plastic initiation and elastic-plastic expansion.

        A computer program is developed for evaluating the stress distribution. The solution is carried out for worst boundary conditions when the cylinder is subjected to the combination of pressure load, inertia load, and temperature gradient.

        The results are presente

In this paper,the homtopy perturbation method (HPM) was applied to obtain the approximate solutions of the fractional order integro-differential equations . The fractional order derivatives and fractional order integral are described in the Caputo and Riemann-Liouville sense respectively. We can easily obtain the solution from convergent the infinite series of HPM . A theorem for convergence and error estimates of the HPM for solving fractional order integro-differential equations was given. Moreover, numerical results show that our theoretical analysis are accurate and the HPM can be considered as a powerful method for solving fractional order integro-diffrential equations.

The goal of our study is to perform detailed multiband surface photometry of the spiral galaxy NGC 4448 and its brightest star-forming regions. The structure and composition of the stellar population in the surface brightness galaxy NGC 4448 was studied using BVR CCD photometry. The observations were obtained on the 1.88 m optical telescope of Kottamia Astronomical Observatory (KAO), Egypt. A two-dimensional decomposition of the galaxy bulge and disk components is carried out. A powerful star forming region is observed near the galactic center. Based on the positions of the various components of the galaxy in two color diagrams. From the observations, the surface brightness profiles, Ellipticity profiles, position angle profiles and colo

Nanocrystal-ZnS-loaded graphene was synthesized by a facile co-precipitation route. The Graphene was affected on the characterization of ZnS which has been investigated. XRD results reveal that ZnS has a cubic system while the hexagonal structure has been observed by loading graphene during preparation ZnS. D.c-conductivity proves that ZnS and ZnS/Gr have semiconductor behavior. The sensing properties of ZnS/Gr against NO₂ gas were investigated as a function of operating temperature and time under optimal condition. The sensitivity, response time and recovery time were calculated with different operating temperatures (100, 150, 200)^oC.

Total Electron Content measurements derived from Athens station ionograms (ITEC),
located near Iraq, during the ascending phase of solar cycle 24 (July 2009- April 2010),
according to availability of data, are compared with the latest version of the International
Reference Ionosphere model, IRI-2012 (IRI TEC), using two options (NeQuick, IRI01-
Corr) for topside electron density.
The results obtained from both (ITEC and IRI TEC) techniques were similar, where
correlation coefficients between them are very high. Generally, the IRI predictions
overestimate the ITEC values.

The aim of this study is to the evaluation of the general hydrogeology condition of the Al-Khassa sub-basin area. Pumping test has been done for five wells in the area. The hydrogeological characteristics (transmissivity, hydraulic conductivity and storage coefficient) were determined in the area by input data which obtained from the pumping test process into the (AquiferWin32, Version 5) software program. The data were analyzed using Copper-Jacob, Theis and Hantuosh methods for pumping, the values of hydraulic characteristics range from: transmissivity (0.98 to 19.57) m²/day in (W7-W9-W10-W12) sites and 416 m²/day in W1, hydraulic conductivity (0.051 to 0.305) m/day in (W7-W9-W10-W12) sites and 5.012 m/day in W1, storage coefficie

Abstract

   The extremes effects in parameters readings which are BOD (Biological Oxygen Demands) and DO(Dissolved Oxygen) can caused error estimating of the model’s parameters which used to determine the ratio of de oxygenation and re oxygenation of the dissolved oxygen(DO),then that will caused launch big amounts of the sewage pollution  water to the rivers and it’s turn is effect in negative form on the ecosystem life and the different types of the water wealth.

   As result of what mention before this research came to employees Streeter-Phleps model parameters estimation which are (K_d,K_r) the de oxygenation and re oxygenation ratios on respect

In this research study failed Annunciation No. 10 for the fourth phase of the pressure of carbon dioxide of the company for Southern Fertilizers and repeated the failures more than once for the same gospel was a detailed study of the gospel included a series tests for properties Mechanical and Structural addition to the tests microscopic and scanning electron microscope shows m This study parameters and a failure Elal well as the existence of an old internal cracks in the metal of the Annunciation

In this work, different soil samples were brought to study and analyse the element concentrations from different middle regions of Iraq (such as, Habbaniah, Garmah, Fallujah, and Tarmiah cities). Using laser-induced breakdown spectroscopy (LIBS) has been documented as an atomic emission spectroscopy (AES) technique.  Laser-induced plasma utilized to analyse elements in materials (gases, liquids, and solids) in order to analyse elements in materials (gases, liquids and solid). The Nd:YAG laser excitation source at 1064nm with pulse width and pulse duration of 9ns is used to generate power density of 5.5 x 10¹² MW/mm², with optical spectrum in the range 320 -740 nm.

The soils of Habbaniyah and Garmah citi

The compressive residual stresses generated by shot peening, is increased in a direct proportional way with shot peening time (SPT). For each metal, there is an optimum shot peening time (O.S.T) which gives the optimum fatigue life. This paper experimentally studied to optimize shot peening time of aluminium alloy 6061-T651 as well as using of and analysis of variance (ANOVA).

Two types of fatigue test specimens’ configuration were used, one without notch (smooth) and the other with a notch radius (1,25mm), each type was shot peened at different time. The (O.S.T) was experimentally estimated  to be 8 minutes reaching the surface stresses at maximum peak of -184.94 MPa.

A response surface methodology (RSM) is presen