For many problems in Physics and Computational Fluid Dynamics (CFD), providing an accurate approximation of derivatives is a challenging task. This paper presents a class of high order numerical schemes for approximating the first derivative. These approximations are derived based on solving a special system of equations with some unknown coefficients. The construction method provides numerous types of schemes with different orders of accuracy. The accuracy of each scheme is analyzed by using Fourier analysis, which illustrates the dispersion and dissipation of the scheme. The polynomial technique is used to verify the order of accuracy of the proposed schemes by obtaining the error terms. Dispersion and dissipation errors are calculated and compared to show the features of high order schemes. Furthermore, there is a plan to study the stability and accuracy properties of the present schemes and apply them to standard systems of time dependent partial differential equations in CFD.
4-methylaniline and its Schiff base derivative were intercalated into the Bentonite clay interlayers in a solid state reaction followed by a condensation reaction to produce two organo-clay composites. X-ray diffraction was used to identify the changes in basal spacing of montmorillonite layers which exhibited noticeable alteration before and after the formation of the composites. FT-IR spectra, on the other hand, were utilized for identifying the structural compositions of the prepared materials as well as the formation of the intercalated Schiff base derivative. The surface morphology of the composites was examined by Scanning Electron Microscopy SEM and Atomic Force Microscope AFM, which reflected some differences in the surface of prepa
... Show MoreVisible-light photodetectors constructed Fe2O3 were manufactured effectively concluded chemical precipitation technique, films deposited on glass substrate and Si wafer below diverse dopant (0,2,4,6)% of Cl, enhancement in intensity with X-ray diffraction analysis was showed through favored orientation along the (110) plane, the optical measurement presented direct allowed with reduced band gap energies thru variation doping ratio , current–voltage characteristics Fe2O3 /p-Si heterojunction revealed respectable correcting performance in dark, amplified by way of intensity of incident light, moreover good photodetector properties with enhancement in responsivity occurred at wavelength between 400 nm and 470 nm.
The esterification of oleic acid with 2-ethylhexanol in presence of sulfuric acid as homogeneous catalyst was investigated in this work to produce 2-ethylhexyl oleate (biodiesel) by using semi batch reactive distillation. The effect of reaction temperature (100 to 130°C), 2-ethylhexanol:oleic acid molar ratio (1:1 to 1:3) and catalysts concentration (0.2 to 1wt%) were studied. Higher conversion of 97% was achieved with operating conditions of reaction temperature of 130°C, molar ratio of free fatty acid to alcohol of 1:2 and catalyst concentration of 1wt%. A simulation was adopted from basic principles of the reactive distillation using MATLAB to describe the process. Good agreement was achieved.
Formulations based on nanomaterials have the ability to reduce the consuming of hazardous pesticides and theirimpact on human health and environment. The present study focused on a comparative investigation of histological effects of nanocapule acetamiprid (NACMP) in vivoand commercial parental bulk form of acetamiprid (ACMP) on albino mice. Nanoformulations of pesticides have the potential to improve food productivity without compromising with the ecosystem. In the present study, nanocapsules containing acetamiprid were prepared from two natural macromolecules, alginate and chitosan. The characterization of the nanocapsules were investigated by Dynamic Light Scattering(DLS), T ransmission Electron Microscopy (TEM) and Atomic force
... Show MoreAlpha-tocopherol acetate is one of the most important vitamin E derivatives,that were used as antioxidants. Adsorbents like kaolin, magnesium carbonate, and microcrystalline cellulose were used successfully to incorporate oily alpha-tocopherol acetate into an acceptable powder dosage form. The results revealed that microcrystalline cellulose as an adsorbents gave the best results with 50% loading capacity at time, 8 minutes before and after incubation period (3 months at 30C°), while kaolin and magnesium carbonate have been shown a significant difference before and after incubation. Addition of 1% w/w magnesium carbonate to the kaolin enhanced the loading capacity by decreasing the time of adsorption from 20 to 6 minutes and 47
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