In this article, Pb2Ba1.7Sr0.3Ca2Cu3O10+δ superconductor material was synthesized using conventional solid-state reaction method. X-ray diffraction (XRD) analysis demonstrated one dominant phase 2223 and some impurities in the product powder. The strongest peaks in the XRD pattern were successfully indexed assuming a pseudo-tetragonal cell with lattice constants of a = 3.732, b = 3.733 and c = 14.75 Å for a Pb-Based compound. The crystallite size and lattice strain between the layers of the studied compound were estimated using several methods, namely the Scherrer, Williamson-Hall (W.H), sizestrain plot (SSP) and Halder Wagner (H.W) approach. The values of crystallite size, calculated by Scherrer, W.H, SSP and H.W methods, were 89.4540774, 86.658638, 87.7555823 and 85.470086 Å, respectively. Moreover, the lattice strain values obtained by W.H, SSP and H.W methods were 0.0063240, 0.006325 and 0.006, respectively. It was noted that all crystallite size results are consistent; however, the best method is the size-strain plot because it gave a value of R2 approaching one. Furthermore, degree of crystallites was calculated and found to be 59.003321%. Resistivity analysis suggests zero-resistance, which is typical of superconducting materials at critical temperature. Four-probe technique was utilized to measure the critical temperature at onset Tc(onset), zero resistivity Tc(off set), and transition (width ΔT), corresponding to temperatures of 128 K, 116 K, and 12 K, respectively.
The present study focused mainly on the analysis of stiffened and unstiffened composite laminated plates subjected to buckling load. Analytical, numerical and experimental analysis for different cases has been considered. The experimental investigation is to manufacture the laminates and to find mechanical properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus. The compressive test was carried to find the critical buckling load of plate. The design parameters of the laminates such as aspect ratio, thickness ratio, boundary conditions and number of stiffeners were investigated using high order shear deformation theory (HOST) and Finite element coded by ANSYS .The main conclusion was the buckling load c
... Show MoreIn this study, the induced splined shaft teeth contact and bending stresses have been investigated numerically using finite element method(Ansys package version 11.0) with changing the most effecting design parameter,(pressure angle, teeth number, fillet radius and normal module), for internal and external splined shaft. Experimental work has been achieved using two dimensional photoelastic techniques to get the contact and bending stresses; the used material is Bakelite sheet type “PSM-4”.
The results of numerical stress analysis indicate that, the increasing of the pressure angle and fillet radius decrease the bending stress and increase the contact stress for both internal and external spline shaft teeth while the increasing of
With the aim of developing potential antimicrobials, a series of new 5-fluoroisatin derivatives incorporated with different secondary amines (piperidine, morpholine, pyrrolidine, dimethylamine, and diphenylamine) for monomer, and (piperazine) in case of dimer Mannich bases, separately in presence of formaldehyde to obtain Mannich bases of 5-fluoroisatin derivatives, which then each Mannich derivatives reacts with phenylhydrazine to form Schiff bases as final products. The resulting compounds were characterized by two spectroscopic analyses; (Fourier- transform infrared) FT-IR and proton nuclear magnetic resonance spectroscopy (¹H-NMR). In addition, the in vitro antibacterial and antifungal activities were tested against some human pathogen
... Show Moreالهدف من الدراسه تحضير فئه جديده من بوليمرات السليكون P1-P4 والتي تمت على اساس استحدام ثنائي مثيل ثنائي كلورو سيلان((DCDMS مع بعض المركبات العضويه التي تحتوي مجاميع الهيدروكسيل الطرفيه والتي حضرت لاول مره M1-M4، بأستخدم البلمره التكثيفيه .كما تم تحضير متراكباتها النانويهP′1-P′4 بوجود جسيمات الفضه النانويه (Ag-NPs) باستخدام طريقة صب المحاليل. شخصت جميع التراكيب للمونمرات والبوليمرات المحضره باستخدام مطيافية
... Show MoreIraqi oil crudes have some of the physical and chemical characteristics that distinguish it from other types of oil crudes in the world. Some of these features such us molecular composition, rheological, viscosity and emulsions are studied carefully by researchers. In this work, a comparative study of the linear and the non-linear optical properties for typical heavy and light crude oils of Iraqi origin was studied utilizing Z-scan technique. The He -Ne laser of wavelength 632.8 nm had been used for this purpose. These samples were collected from Basra and Kut oil fields. The values of the non-linear refractive index (n2), non-linear absorption coefficient (β), and third-order electrical susceptibility (χ3) were e
... Show MoreThe aim of this study is to find a relationship between oxidative stress and adiponectin in Iraqi patients with acromegaly. The present study included 30 patients with acromegaly disease attending at Al-Yarmuk teaching hospital , and 30 healthy individuals as a control group.The two groups with ages ranging (30-55) years. The results revealed a highly significant elevation in all parameters (GH,IGF-1 , adiponectin , malondialdehyde , and peroxynitrite ) levels in sera of patients when compared with healthy control .It can be concluded that oxidative stress (malondialdehyde and peroxynitrite ) may be valuable in detecting of endocrine diseases like acromegaly .
Solid dispersion (SD) is one of the most widely used methods to resolve issues accompanied by poorly soluble drugs. The present study was carried out to enhance the solubility and dissolution rate of Aceclofenac (ACE), a BCS class II drug with pH-dependent solubility, by the SD method. Effervescent assisted fusion technique (EFSD) using different hydrophilic carriers (mannitol, urea, Soluplus®, poloxamer 188, and poloxamer 407) in the presence of an effervescent base (sodium bicarbonate and citric acid) in different drug: carrier: effervescent base ratio and the conventional fusion technique (FSD) were used to prepare ACE SD. Solubility, dissolution rate, Fourier transformation infrared spectroscopy (FTIR), PowderX-ray diffraction
... Show MoreThe aim of this study is to find a relationship between oxidative stress and adiponectin in Iraqi patients with acromegaly. The present study included 30 patients with acromegaly disease attending at Al-Yarmuk teaching hospital , and 30 healthy individuals as a control group.The two groups with ages ranging (30-55) years. The results revealed a highly significant elevation in all parameters (GH,IGF-1 , adiponectin , malondialdehyde , and peroxynitrite ) levels in sera of patients when compared with healthy control .It can be concluded that oxidative stress (malondialdehyde and peroxynitrite ) may be valuable in detecting of endocrine diseases like acromegaly .
This work introduces a new electrode geometry for making holes with high aspect ratios on AISI 304 using an electrical discharge drilling (EDD) process. In addition to commercially available cylindrical hollow electrodes, an elliptical electrode geometry has been designed, manufactured, and implemented. The principal aim was to improve the removal of debris formed during the erosion process that adversely affects the aspect ratio, dimensional accuracy, and surface integrity. The results were compared and discussed to evaluate the effectiveness of electrode geometry on the machining performance of EDD process with respect to the material removal rate (MRR,) the electrode wear rate (EWR), and the tool wear ratio (TWR). Dimensional features an
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