In this work, porous Silicon structures are formed with photochemical etching process of n-type Silicon(111) wafers of resistivity (0.02.cm) in hydrofluoric acid (HF) of concentration (39%wt) under light source of tungeston halogen lamp of (100 Watt) power. Samples were anodized in a solution of 39%HF and ethanol at 1:1 for 15 minutes. The samples were realized on n-type Si substrates Porous Silicon layers of 100m thickness and 30% of porousity. Frequency dependence of conductivity for Al/PSi/Si/Al sandwich form was studied. A frequency range of 102-106Hz was used allowing an accurate determination of the impedance components. Their electronic transport parameters were determined using complex impedance measurements. These measu

The nanocrystalline porous silicon (PS) films are prepared by electrochemical etching ECE of p -type silicon wafer with current density (10mA/cm ) and etching times on the formation nano -sized pore array with a dimension of around different etching time (10 and 20) min. The films were characterized by the measurement of XRD, atomic force microscopy properties (AFM). We have estimated crystallites size from X -Ray diffraction about nanoscale for PS and AFM confirms the nanometric size Chemical fictionalization during the electrochemical etching show on the surface chemical composition of PS. The atomic force microscopy investigation shows the rough silicon surface, with increasing etching process (current density and etching time) porous st

The research work represent a fast and simple method for the determination of methionine using chemiluminescence for the methionine-sodium hydroxide-luminol for the generation of a chemiluminesecent derivative of luminal. The emission was measured by continuous flow analysis made sample size of 83µL was used.Response versus concentration extended from 0.2-20 mM.L-1 with a percentage linearity of 96.17% or with 99.17% percentage of linearity for the range 0.6-20 mM.L-1. Reaching to a L.O.D. at (S/N=3) for 5 µM.L-1 from the gradual dilution for the minimum concentration in the calibration graph with a repeatability of less than 0.5% (n=10). A comparison was made between the new developed method with the classical method for the spectrophoto

        In this study we focused on the determination of influence the novel synthesized thiosemicarbazide derivative "2-(2-hydroxy-3-methoxybenzylidene) hydrazinecarbothioamide" (HMHC) influenced the corrosion inhibition of mild steel (MS) in a 1.0 M hydrochloric acid acidic solution.This is in an effort to preserve the metal material by maintaining it from corrosion.The synthesized inhibitor was characterized using elemental analysis, and NMR-spectroscopy. Then the corrosion inhibition capability of (HMHC) was studied on mild steel in an acidic medium by weight loss technique within variables [temperature, inhibitor concentration, and time]. The immersion periods were [1:00, 3:00, 5:00, 10:00, 24:00, and 72:00] hours and the tem

Titanium-dioxide (TiO₂) nanoparticles suspended in water, and ethanol based fluids have been prepared using one step method and characterized by scanning electron microscopy (SEM), and UV–visible spectrophotometer. The TiO₂ nanoparticles were added to base fluids with different volume concentrations from 0.1% to1.5% by dispersing the synthesized nanoparticles in deionized water and ethanol solutions. The effective thermal conductivity, viscosity and pH of prepared nanofluids at different temperatures from 15 to 30 ^oC were carried out and investigated. It was observed that the thermal conductivity, pH, and viscosity of nanofluids increases with the increase in TiO₂ nanoparticle volume fraction

In this work, the effect of ceramic coating on performance, exhaust gas temperature and gases emissions of diesel engine operated on diesel fuel and biodiesel blends was investigated. A conventional four stroke, direct injected, single cylinder, diesel engine was tested at constant speed and at different load conditions using diesel fuel and biodiesel blends. The inlet and exhaust valves, the head of piston and cylinder head of the engine were coated by ceramic materials. Ceramic layers were made of (210-240) μm of Al2O3 and (30-60) μm of 4NiCr5Al as a bond coat for inlet and exhaust valves and (350-400) μm of YSZ and (50-100) μm of 4NiCr5Al as a bond coat for head of piston and (280-320) μm of Sic and (40-80) μm of 4NiCr5Al as a b

Pulsatile drug delivery systems are time-controlled dosage forms which are designed to release the active pharmaceutical ingredient after a predetermined lag time to synchronize the disease circadian rhythm. A migraine shows circadian rhythm with a marked increase in attacks between 6 a.m. and 8 a.m.

Sumatriptan is a selective agonist at serotonin (5-Hydroxy tryptamine1  (5-HT1))receptors, is an effective treatment for acute migraine attacks.

The aim of this work is to prepare time-controlled press-coated tablet with a lag time of 5.45 hrs.

Six formulas of fast dissolving core tablets and three formulas of press-coated tablets were prepared by using direct compression method using different variables to prepa

This study investigates the characterization and mechanical performance of Stone Mastic Asphalt (SMA) mixtures modified with two types of polymers: styrene–butadiene–styrene (SBS) and high-molecular-weight polyethylene (PE). Neat asphalt cement PG 64-16 was modified using a higher content of SBS and PE at concentrations of 6%, 7%, and 8% by weight of asphalt through the dry blending method to produce Highly Modified Asphalts (HiMA). The physical and rheological properties of the modified binders were evaluated using penetration, softening point, rotational viscosity, and dynamic shear rheometer (DSR) tests. Also, their phase compatibility and morphological changes were evaluated using the storage stability testing and scanning electron

The 3-parameter Weibull distribution is used as a model for failure since this distribution is proper when the failure rate somewhat high in starting operation and these rates will be decreased with increasing time .

In practical side a comparison was made between (Shrinkage and Maximum likelihood) Estimators for parameter and reliability function using simulation , we conclude that the Shrinkage estimators for parameters are better than maximum likelihood estimators but the maximum likelihood estimator for reliability function is the better using statistical measures (MAPE)and (MSE) and for different sample sizes.

Note:- n_s : small sample ; n_m=median sample