Silicon nanowire arrays (SiNWs) are created utilizing the metal-assisted chemical etching method with an Ag metal as a catalyst and different etching time of 15, 30, and 60 minutes using n-Si (100). Physical properties such as structural, surface morphology, and optical properties of the prepared SiNWs are studied. The diameter of prepared SiNWs ranged from 20 to 280 nm, and the reflectance in the visible part of the wavelength spectrum was less than 1% for all prepared samples. The obtained energy gap of prepared SiNWs was around 2 eV, which is higher than the energy gap of bulk silicon. X-ray diffraction (XRD) has diffraction peaks at 68.70o for all prepared samples. The heterojunction solar cell was fabricated based on the
... Show MoreNew compounds containing heterocyclic units have been synthesized. These compounds include 2-amino 5- phenyl-1,3,4-thiadiazole (1) as starting material to prepare the Schiff bases 2N[3-nitrobenzylidene -2 hydroxy benzylidene and 4-N,N-dimethyl aminobenzylidene] -5-phenyl-1,3,4-thiadiazole (2abc) , 2N[3-nitrophenyl, 2-hydroxyphenyl or 4-N,N-dimethylaminophenyl] 3-]2-amino-5-phenyl-1,3,4-thiadiazole]-2,3-dihydro-[1,3]oxazepine-benzo-4,7-dione] (3abc), 2N[3-nitrophenyl,2-hydroxyphenyl,4-N,N-dimethylaminophenyl]-3-[2-amino-5-phenyl-1,3,4-thiadiazole-2-yl]-2,3-dihydro-[1,3]oxazepine-4,7-dione[(4abc), 2-N-[3-nitrophenyl, 2-hydroxyphenyl or 4-N,N-dimethylaminophenyl]-3-[2-amino-5-phenyl-1,3,4-thiadiazole-2yl]-1,2,3-trihydro-benzo-[1,2-e][1,3] diaz
... Show MoreIraqi kaolin was used for the preparation and characterization of NaY zeolite for biodiesel production via esterification reaction. Oleic acid was used usually as a typical simulated feedstock of high acid number for the esterification reaction.
The chemical composition for the prepared Nay zeolite is as following: (Ca2.6Na1.K0.1)(Al6.3Si17.7)O48.16H2O, the silica to alumina ratio in the prepared catalyst was found equal to 2.6 and Na2O content was 12.26 wt. %, with relative crystallinity equal to 147.4 % obtained by the X-ray diffraction. The surface area result shows that the prepared catalyst has 330 m2
... Show MoreThis research includes the synthesis, characterization, and investigation of liquid crystalline properties of new rod-shaped liquid crystal compounds 1,4- phenylene bis(2-(5-(four-alkoxybenzylidene)-2,4-dioxothiazolidin-3- yl)acetate), prepared thiazolidine-2,4-dione (I) by the thiourea reaction with chloroacetic acid and water in the presence of the concentrated hydrochloric acid. The n-alkoxy benzaldehyde (II)n synthesized from the reacted 4- hydreoxybenzaldehyde and n-alkyl bromide with potassium hydroxide, and then the compound (I) was reacted with (II)n in the presence of piperidine to produce compounds (III)n. Also, hydroquinone was converted into a corresponding compound (IV) by refluxing with two moles of chloracetyl chloride in pyr
... Show MoreThe n-type Au thin films of 500nm thickness was evaporated by thermal evaporation method on p-type silicon wafer of [111] direction to formed Au/Si heterojunction solar cell. The AC conductivity, C-V and I-V characteristics of fabricated c-Au/Si diffusion heterojunction-(HJ) solar cell, has been studied. The first methods demonstrated that the AC conductivity due to with diffusiontunneling mechanism, while the second show that, the heterojunction profile is abrupt, the heterojunction parameters have been played out, such as the depletion width, built-in voltage, and concentration. And finally the third one show that the c-Au/Si HJ has rectification properties, and the solar cell yielded an open circuit voltage of (Vic) 0.4V, short circuit c
... Show MoreFrom 144 specimens of tonsillitis which were collected from patient, (children of 3 -12 year olds) there were 70 isolates beta hemolytic and 28 isolates were identified as S. pyogenes. Sensitivity of S. pyogenes isolates to antibiotics was tested, all isolates were sensitive to amoxicillin and cephaloxia while higher resistant were to erythromycin. One isolate whiche was 100 A had a stable characteristics and produce pyrogenic toxin was chosen for study and it was purified and characterized from the cell free supernatant of S. pyrogenes strain.
Starting from 4, - Dimercaptobiphenyl, a variety of phenolic Schiff bases (methylolic, etheric, epoxy) derivatives have been synthesized. All proposed structure were supported by FTIR, 1H-NMR, 13C-NMR Elemental analysis all analysis were performed in center of consultation in Jordan Universty.
Ni-Co-Mn-Mg ferrite nanoparticles with the formula (Ni,Co)xMn0.25-xMg0.75Fe2O4 were synthesized in this work by employing the sol-gel auto-combustion process, with nitrates used as the cations source and citric acid (C6H8O7) as the combustion agent. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), and a vibrating sample magnetometer (VSM) were used to characterize the structural, morphological, and magnetic properties of ferrite powders. The XRD measurements showed crystallite sizes ranging between 24 - 28 nm. The FE-SEM images show the presence of agglomeration as well as a non-homogeneous distribution of the samples. On the other hand, the stoichiometry of the react
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