Manganese-zinc ferrite MnxZn1-xFe2O4 (MnZnF) powder was prepared using the sol-gel method. The morphological, structural, and magnetic properties of MnZnF powder were studied using X-ray diffraction (XRD), atomic force microscopy (AFM), energy dispersive X-ray (EDX), field emission-scanning electron microscopes (FE-SEM), and vibrating sample magnetometers (VSM). The XRD results showed that the MnxZn1-xFe2O4 that was formed had a trigonal crystalline structure. AFM results showed that the average diameter of Manganese-Zinc Ferrite is 55.35 nm, indicating that the sample has a nanostructure dimension. The EDX spectrum revealed the presence of transition metals (Mn, Fe, Zn, and O) in Mang
... Show MoreThree phenol-formaldehyde resins having pendant maleimides were prepared by poly condensation of N-(hydroxyphenyl) maleimides with formaldehyde under conditions similar to those in Novolac preparation. The prepared resins were modified by two methods, the first one includes esterification of phenolic hydroxyl groups in the prepared resins via their treatment with benzoyl, acryloyl, methacryloyl and cinnamoyl chlorides respectively in the presence of triethylamine, while the second modification includes free radical polymerization of vinylic bonds in the prepared resins to produce cross-linked thermally stable polymers.
This study includes synthesis, characterization three series of the new derivatives via schiff bases for ampicillin which known as a high medicinal effectiveness. Series A include preparation schiff bases (A1-A6) by condensation of ampicillin with many substituted aldehyedes, while series B include preparation of six amines (B1-B6) is hydrazine hydrate derivatives by reaction schiff bases compounds which prepared in series A with hydrazine hydrate, then series C included for preparation of new six polymers C1-C6 by reaction of poly methyl methacrylate with amine compounds which prepared in series B. The synthesized polymers were identified by spectroscopic methods (FT-IR and 1 H-NMR) and measurement some of its physical characteristics.
CuO nanoparticles were synthesized in two different ways, firstly by precipitation method using copper acetate monohydrate Cu(CO2CH13)2·H2O, glacial acetic acid (CH3COOH) and sodium hydroxide(NaOH), and secondly by sol-gel method using copper chloride(CuCl2), sodium hydroxide (NaOH) and ethanol (C2H6O). Results of scanning electron microscopy (SEM) showed that different CuO nanostructures (spherical and Reef) can be formed using precipitation and sol- gel process, respectively, at which the particle size was found to be less than 2 µm. X-ray diffraction (XRD)manifested that the pure synthesized powder has no inclusions that may exist during preparations. XRD result
... Show MoreThe triggering effect for the face pumping of Nd:YVO4 disc medium of 4×5×0.5 mm was investigated using bulk diode laser at different resonator cavity length in pulse mode and at repetition rate of 1.3kHz. The maximum emitted peak power was found to be 100, 82, and 66 mW for resonator lengths of 10, 13.5, and 17.5 cm respectively, while the threshold pumping power was found to be 41mW. The maximum emitted peak power obtained was 300 mW when using external triggering and 10cm length, with repetition of 3Hz.
The Cu2SiO3 composite has been prepared from the binary compounds (Cu2O, and SiO2) with high purity by solid state reaction. The Cu2SiO3 thin films were deposited at room temperature on glass and Si substrates with thickness 400 nm by pulsed laser deposition method. X-ray analysis showed that the powder of Cu2SiO3 has a polycrystalline structure with monoclinic phase and preferred orientation along (111) direction at 2θ around 38.670o which related to CuO phase. While as deposited and annealed Cu2SiO3 films have amorphous structure. The morphological study revealed that the grains have granular and elliptical shape, with average diameter of 163.63 nm. The electrical properties which represent Hall effect were investigated. Hall coeffici
... Show MoreThe aim of this research is to study the effect of welded joint design (Butt joint and lap joint) on thejoint strength during tension and fatigue loading with different current of welding (40,50,60,70,80) ^per, and different type of wire welding. The result of this research is showed that the effect of fatigue loading on the type of joint is more than the effect of tension loading on it. And the butt joint welding is better than the lap joint welding during the fatigue loaded.The experimental results of the effect of W'elding current showed that more increasing and more decreasing the value of the heat input, during the welding was found to produce mechanical brittleness on the buttjoint welding during the static and dynamic loading. Also i
... Show MoreIn this study, reduced graphene oxide (rGO) was synthesized from graphene oxide (GO) via an ascorbic acid-assisted reduction process. GO was synthesized from graphite powder using a modified Hummers technique. The surface morphology, structure, functional groups, and elemental compositions of the produced materials were studied using various methods, such as scanning electron microscopy (SEM)/EDX, X-ray diffraction (XRD), atomic force microscopy (AFM), Fourier transform infrared (FTIR), and UV-Vis. The removal of oxygen-containing functional groups in rGO through reduction resulted in poor sample quality. In addition, FTIR investigations revealed that GO contained more oxygen-containing functional groups than rGO. Typical peaks at 2
... Show Moreفي البداية اود الاشارة الى ان فهم حقيقة الازمة هو ذو جانب فني يتعلق بالجينات الوراثية لنظام يملك في احيناته قدرة عالية على تفريخ المشتقات. هذا النظام الذي يزداد عقما وتدميرا يزداد قدرة على خلق النقود الائتمانية/المشتقات، وكلما اقتربنا اكثر من فهم هذا الجانب كلما اسقطت في ايدينا تلك التوصيفات الاكاديمية الجاهزة في نقص الرقابة والاشراف، تركيز المخاطر،....الخ التي تناولتها الكتابات الشائعة في معظم طروحات
... Show More