Erbium, as optical probe, doped silicate sol-gel glass with
different Er concentrations was formed by wet chemical synthesis
method using ethanol, water and tetraethaylorthosilicate
[Si(OC2H5)4] precursor. Erbium ions were incorporated into silica
sol-gel matrix via dissolution of Erbium chloride solution into the
initial Si(OC2H5)4 precursor sol. Aluminum (Al) as a co-dopant was
added to the final precursor in the form of Aluminum chloride
(AlCl3) solution. The prepared samples were analyzed using atomic
absorption analysis, X-ray diffraction and spectroscopic tests. The
experimental results concerned with the transmission spectra suggest
that the final samples have a good transparency and homogeneity.
Also, the X-ray diffraction test showed that they have amorphous
structure. The absorption and fluorescence spectra, as a function of
Er concentration, were recorded at room temperature. Fluorescence
emission of the 4I13/2→4I15/2 transition at ~ 1.536 μm was observed.
In addition, the high values of peak emission cross-section, which
were calculated as a function of Er concentration, suggest that the Er
in the sol-gel may be favorable as optical material
This Paper aims to know the modern approaches of determining the Qiblah and its ruling in Islamic Faqah, as well as to find out the required in the identity of the Qiblah or the eye, and the care of the advanced Jurists in this matter, and to present some of their sayings on the issue. we have followed the Descriptive analytical method of the aspects of the jurists ’difference in what is required when facing the qiblah either the eye or aspect, the approach of several demands branched out from each topic, which were answered in the theoretical framework of the research, and the research concluded with the most important results: The need to receive the eye of the qiblah for the worshiper who is close to it and it is no
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This study explains the effect of non-thermal (cold) plasma on wound of diabetic rats by (FE-DBD) system, 3cm probe diameter is used. The output power was ranged from (12-20) W. The effect of non-thermal plasma on wounds of a diabetic was observed with different exposure durations (20,30) sec., the plasma exposure duration decreases the sugar level in blood and the diameter of the wound. These results indicate the cold plasma can be used to enhance the insulin level (i.e., blood sugar) and wounds treatment.
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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Diverting river flow during construction of a main dam involves the construction of cofferdams, and tunnels, channels or other temporary passages. Diversion channels are commonly used in wide valleys where the high flow makes tunnels or culverts uneconomic. The diversion works must form part of the overall project design since it will have a major impact on its cost, as well as on the design, construction program and overall cost of the permanent works. Construction costs contain of excavation, lining of the channel, and construction of upstream and downstream cofferdams. The optimization model was applied to obtain optimalchannel cross section, height of upstream cofferdam, and height of downstream cofferdamwith minimum construction cost
... Show MoreObjective(s): This study aims to evaluate the hardness of two commercially available cold cured acrylic resin material
(Vertex and PAN) when polymerized at different temperature in comparison to those polymerized by conventional
methods in air at 23C ± 5C.
Methodology: Eighty specimens, forty from cold cured acrylic (Vertex Type) and forty from cold cured acrylic (PAN
type) were prepared, flasking and packing procedure were done according to manufacturer direction and divided
according to processing as follow: 20 specimens (10 from Vertex type and 10 from PAN type) were processed in air for
two hours at 23C ± 5C under press (bench curing) as a control, and 60 specimens (30 from Vertex type and 30 from
PAN type) wer
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In this work, the spectra for plasma glow produced by pulse
Nd:YAG laser (λ=532 and 1064nm) on Ag:Al alloy with same molar
ratio samples in distilled water were analyzed by studying the atomic
lines compared with aluminum and silver strong standard lines. The
effect of laser energies of the range 300 to 800 mJ on spectral lines,
produced by laser ablation, were investigated using optical
spectroscopy. The electron temperature was found to be increased
from 1.698 to 1.899 eV, while the electron density decreased from
2.247×1015 to 5.08×1014 cm-3 with increasing laser energy from 300
to 800 mJ with wavelength of 1064 nm. The values of electron
temperature using second harmonic frequency are greater than of<
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