The grapheme Flakes were prepared by reduction graphite oxide which was prepared by Hummer’s method. X-ray diffraction (XRD) pattern showed that the graphene oxide have a sharp peak at (001) with d-spacing d001= 7.4Å at angle 2ϴ=11.85˚and graphene has broad peak at (002) with d-spacing d002=3.4Å at angle 2ϴ= 25.72˚ with lattice constant (a=2.47 Å). The particle size was calculated by using equation Debye - Scherer and Williamson - Hall equations, Scanning electron microscopy examination and particle size analyzer proved that the graphene Flakes were in nano size. Also the surface area of nanoparticles showed a value 270 m2/g . The micrographs of (scanning electron microscopy) showed that graphene oxide has a fluffy aggregation and the form of graphene as a flakes or nano-sheets.
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Using photo electrochemical etching technique (PEC), porous silicon (PS) layers were produced on n-type silicon (Si) wafers to generate porous silicon for n-type with an orientation of (111) The results of etching time were investigated at: (5,10,15 min). X-ray diffraction experiments revealed differences between the surface of the sample sheet and the synthesized porous silicon. The largest crystal size is (30 nm) and the lowest crystal size is (28.6 nm) The analysis of Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscope (FESEM) were used to research the morphology of porous silicon layer. As etching time increased, AFM findings showed that root mean square (RMS) of roughness and po
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A simple method was used to create a graphene oxide/chitosan (GO/CS) nanocomposite, which was then used in batch experiments to remove copper ions from industrial wastewater under various conditions of initial concentration, adsorbent weight, pH, and contact time. Maximum removal percentage equal to 99.4 % for initial copper ion concentration of 5x10-2 mol/L at pH 6, time 75 min, temperature 25 °C, and adsorbing dose 0.1 g. The pseudo-second order kinetic model and the Freundlich isotherm adequately fit the experimental results. The process was spontaneous and endothermic, according to thermodynamic studies.
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This study included partial purification of the lipase enzyme from the karnel of the pecan nut. After applying ion exchange chromatography technique using CM-Cellulose, two lipase isoenzymes were observed with specific activity values of 2.66 and 1.7 units/mg protein. The highest activity of both isoenzymes appeared at the optimum pH values of 8 and 6 and at temperatures of 40 and 50 °C, respectively. A pure single band was obtained by using electrophoresis technique and it was found that the approximate molecular weight was 42 kDa for the two isoenzymes. The study dealt with the preparation of the diester compound 1,4-diacetoxybenzene, which was diagnosed by GC-MS and 1H NMR spectrometry. When studying the inhibitio
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In the present work, pulsed laser deposition (PLD) technique was applied to a pellet of Chromium Oxide (99.999% pure) with 2.5 cm diameter and 3 mm thickness at a pressure of 5 Tons using a Hydraulic piston. The films were deposited using Nd: YAG laser λ= (4664) nm at 600 mJ and 400 number of shot on a glass substrate, The thickness of the film was (107 nm). Structural and morphological analysis showed that the films started to crystallize at annealing temperature greater than 400 oC. Absorbance and transmittance spectra were recorded in the wavelength range (300-
4400) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of d
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In the present study, the structural properties which included the X-rays diffraction, and DSC, the mechanical properties, which include tensile test, threepoint bending test (Bending Test), hardness test and thermal conductivity of the polymers reinforced with calcite (PVC/CaCO3) at different temperature (25-40-80-
120-160-200-220) °C. The research results showed that the XC degree of X-ray diffraction decreased at high temperatures (220 ˚C), while the inter-polymerized polymer (PVC / CaCO3) increased at high temperatures. The DSC test results showed that the degree of crystallinity (XC) decreases at high temperatures (220 ˚C). The mechanical test results, their values were found to decrease at (
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The work concerned with studying the effect of (SiO2) addition as a
filler on the adhesive properties of (PVA). Samples were prepared as
sheets by using casting method. The mechanical properties showed
that increase in tensile strength from (34MPa) to (68MPa) when
(SiO2) added to (PVA). The adhesive strength showed that joint
properties depend upon specific adhesive characteristic of material
(PVA) and (SiO2\PVA)composites at different concentrations (1.5%,
2.5%, 3.5%, 4.5wt%), the cohesive strength of the adhesive material,
the joint design, and adherent type (Sponge Rubber(SR), Natural
leather (NL), Vulcanized Rubber(VR), and Cartoon). The results
proved the tensile strength increased with (SiO2) ratio, so
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