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bsj-3948
Symmetric and Positive Definite Broyden Update for Unconstrained Optimization
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Broyden update is one of the one-rank updates which solves the unconstrained optimization problem but this update does not guarantee the positive definite and the symmetric property of Hessian matrix.

In this paper the guarantee of positive definite and symmetric property for the Hessian matrix will be established by updating the vector  which represents the difference between the next gradient and the current gradient of the objective function assumed to be twice continuous and differentiable .Numerical results are reported to compare the proposed method with the Broyden method under standard problems.

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Publication Date
Mon Aug 19 2024
Journal Name
Journal Of Metastable And Nanocrystalline Materials
The Structural, Magnetic, and Electrochemical Properties of Composite PAni/Co<sub>0.2</sub>Mn<sub>0.8</sub>Fe<sub>2</sub>O<sub>4</sub>
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The current work concerns preparing cobalt manganese ferrite (Co0.2Mn0.8Fe2O4) and decorating it with polyaniline (PAni) for supercapacitor applications. The X-ray diffraction findings (XRD) manifested a broad peak of PAni and a cubic structure of cobalt manganese ferrite with crystal sizes between 21 nm. The pictures were taken with a field emission scanning electron microscope (FE-SEM), which evidenced that the PAni has nanofibers (NFs) structures, grain size 33 – 55 nm, according to the method of preparation, where the hydrothermal method was used. The magnetic measurements (VSM) that were conducted at room temperature showed that the samples had definite magnetic properties. Additionally, it was noted that the saturation magnetizatio

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Publication Date
Sat Sep 25 2021
Journal Name
International Journal Of Drug Delivery Technology
Synthesis, Characterization Of Some Metal Complexes With 3-(Benzo[d]Thaizole-2-Yl)-9-Oxo-6,7,7a,9-Tertrahydro-2H-2,10:4,7-Diepoxyfuro [3,2-f][1,5,3] Dioxazonine–2,4 (3H)–Dicarboxylic Acid. Hydro-chloride (L–as–am) and Study their Biological Activity
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The reaction of 2-amino-benzothiazole with bis [O,O-2,3,O,O – 5,6 – (chloro(carboxylic) methiylidene) ] – L – ascorbic acid (L-AsCl2) gave new product 3-(Benzo[d]Thaizole-2-Yl) – 9-Oxo-6,7,7a,9-Tertrahydro-2H-2,10:4,7-Diepoxyfuro [3,2-f][1,5,3] Dioxazonine – 2,4 (3H) – Dicarboxylic Acid, Hydro-chloride (L-as-am)), which has been insulated and identified by (C, H, N) elemental microanalysis (Ft-IR),(U.v–vis), mass spectroscopy and H-NMR techniques. The (L-as am) ligand complexes were obtained by the reaction of (L-as-am) with [M(II) = Co,Ni,Cu, and Zn] metal ions. The synthesized complexes are characterized by Uv–Visible (Ft –IR), mass spectroscopy molar ratio, molar conductivity, and Magnetic susceptibility techniques. (

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Publication Date
Mon Sep 20 2021
Journal Name
Key Engineering Materials
Fabrication of Ge<sub>30</sub>Te <sub>70-x</sub>Sb<sub>x</sub> Glasses Alloys and Studying the Effect of Partial Substitution on D.C Electrical Energy Parameters
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The non-linear components has been emphasized for its multiple applications in rewritable recording and data storage devices. Chalcogenide glasses materials are promising due to their high refractive index. In this paper, alloys for Ge30Te70-xSbxglasses semiconductor (where x =0.0, 5, 10, 15 and 20) will be fabricated by melt quenching method. The effect of partial substitution on DC electric power parameters, and its knowledge of electrical conduction mechanisms, were investigated to determine the effect of Antimony on the density of extended states, local states, and in Fermi energy states. The electrical measurements revealed the existence of three conduction mechanis

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Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
Best approximation in b-modular spaces
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In this paper, some basic notions and facts in the b-modular space similar to those in the modular spaces as a type of generalization are given.  For example, concepts of convergence, best approximate, uniformly convexity etc. And then, two results about relation between semi compactness and approximation are proved which are used to prove a theorem on the existence of best approximation for a semi-compact subset of b-modular space.

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Some electrical properties of PVA:PEG/MnCl2 thin film composites
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PVA:PEG/MnCl2 composites have been prepared by adding (MnCl2) to the mixture of the poly vinyl alcohol (PVA) and poly ethylene glycol (PEG) with different weight percentages (0, 2, 4, 6, 8 and 10) wt.% by using casting method. The type of charge carriers, concentration (nH) and Hall mobility (μH) have been estimated from Hall measurements and show that the films of all concentration have a negative Hall coefficient. In D.C measurement increase temperature leads to decrease the electrical resistance. The D.C conductivity of the composites increases with the increasing of the concentration of additive particles and temperature. The activation energy decreases for all composites with increasing the concentration of the additive particles.

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Publication Date
Thu Jan 01 2026
Journal Name
Chalcogenide Letters
Influence of Germanium Substitution on the DC Electrical Properties and Energy Density of States in Pb<sub>50−x</sub>Ge<sub>x</sub>Te<sub>50</sub> Ternary Chalcogenide Alloys
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Publication Date
Mon Sep 01 2025
Journal Name
Iraqi Journal Of Physics
Role of Tin Oxide on the Structural, Optical and Electrical Properties of Pulsed Laser Deposited (ZnO)<sub>1-x</sub>(SnO<sub>2</sub>)<sub>x </sub>Composite Thin Films
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This research examines the electrical, optical, and structural properties of zinc oxide (ZnO) and tin(IV) oxide (ZnO)1-x (SnO2)x composite thin films made by pulsed laser deposition, as well as the impact of composition concentration. The structural study of (ZnO)1-x (SnO2)x composites and thin films was conducted by X-ray analysis (XRD). Optical properties were investigated by UV–Vis infrared spectroscopy. The structural analysis revealed that all prepared thin-film composites were polycrystalline, exhibiting both hexagonal wurtzite and tetragonal phases for pure ZnO and SnO2, as well as a mixture of both phases for x=0.2 and 0.4. In contrast, the SnO2 phase was predominant for x=0.6 and 0.8. The increase in crystal size in the (

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Effect of Nickel Substitution On Structural and Electrical Properties of Hg<sub>0.5</sub>Pb<sub>0.5</sub>Ba<sub>2</sub>Ca<sub>2</sub>Cu<sub>3-y</sub>Ni<sub>y</sub>O<sub>8+δ</sub> Superconductor Composite
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Abstract<p>six specimens of the Hg<sub>0.5</sub>Pb<sub>0.5</sub>Ba<sub>2</sub>Ca<sub>2</sub>Cu<sub>3-y</sub> <italic>Ni<sub>y</sub> </italic>O<sub>8+δ</sub> (y=0.2,0.4,0.6,0.8,1.0) superconducting compound were prepared by solid state reaction method, with sintering temperature equal to 1123K for 24 hours. The electrical resistivity was examined by the four probe technique, It was found that all the specimens have metallic behavior and increasing the critical temperature with increasing nickel concentration. The optimum critical temperature T<sub>c</sub> was found equal </p> ... Show More
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Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
The substitutions of Strontium by yttrium and their effects on Bi<sub>2</sub>Sr<sub>2</sub>-<sub>x</sub>Y<sub>x</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>10</sub>+<sub>δ</sub> superconducting compound
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Abstract<p>Superconducting compound Bi<sub>2</sub>Sr2-<sub>x</sub>Y<sub>x</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>10+δ</sub> were Synthesized by method of solid state reaction, at 1033 K for 160 hours temperature of the sintering at normal atmospheric pressure where substitutions Yttrium oxide with Strontium. When Y2O3 concentration (0.0, 0.1, 0.2, 0.3, 0.4 and 0.5). All specimens of Bi<sub>2</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>10+δ</sub> superconducting compounds were examined. The resistivity of electrical was checked by the four point probe technique, It was found th</p> ... Show More
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Publication Date
Sat Dec 01 2012
Journal Name
International Journal Of Contemporary Mathematical Sciences
Approximation by Convex Polynomials in Weighted Spaces
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Here, we found an estimation of best approximation of unbounded functions which satisfied weighted Lipschitz condition with respect to convex polynomial by means of weighted Totik-Ditzian modulus of continuity