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jih-2798
Birefringence for Elliptical-Core Fibers with Low Ellipticities
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Model birefringence was measured for elliptical-core fibers with low ellipticities, note the birefringence depends strongly on the frequency, especially when fiber is being operated near the higher mode cutoff where ν  for circular fiber of the single-mode type that correspond to the birefringence maximum. When ν  this also correspond to the birefringence maximum that can be introduced in an elliptical core fiber while still operating in the single-mode regime near the higher mode cutoff. Also the birefringence is proportional to the fiber core ellipticity when core ellipticity is much less than unity, but this birefringence deviates from the linear for the large core ellipticities.

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Engineering
Non-Destructive Testing of Carbon Fiber Reinforced Magnetic Reactive Powder Concrete Containing Nano Silica
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This study involves the design of 24 mixtures of fiber reinforced magnetic reactive powder concrete containing nano Silica. Tap water has been used in mixing 12 of these mixtures, while the other 12 have been mixed using magnetic water. Nano Silica (NS) with ratios (1, 1.5, 2, 2.5 and 3) % were used. The results showed that the mixture containing 2.5%NS gives the highest compressive strength at age 7 days. Many different other tests were carried out, the results showed that the fiber reinforced magnetic reactive powder concrete containing 2.5% NS (FRMRPCCNS)  has the higher bulk density, dynamic modulus of elasticity, ultrasonic pulse velocity  electrical resistivity and lesser absorption than fiber reinforced

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Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Improvement of Soil by Using Polymer Fiber Materials Underneath Square Footing
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The change in project cost, or cost growth, occurs from many factors, some of which are related to soil problem conditions that may occurs during construction and/or during site investigation period. This paper described a new soil improvement method with a minimum cost solution by using polymer fiber materials having a length of (3 cm) in both directions and (2.5 mm) in thickness, distributed in uniform medium dense .
sandy soil at different depths (B, 1.5B and 2B) below the footings. Three square footings has been used (5,7.5 and 10 cm) to carry the above investigation by using lever arm loading system design for such purposes.
These fibers were distributed from depth of (0.1B) below the footing base down to the investigated dep

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Publication Date
Sun Jan 13 2019
Journal Name
Iraqi Journal Of Physics
Lorenz model and chaos masking /addition technique
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Publication Date
Sun Jul 30 2023
Journal Name
Iraqi Journal Of Science
IR Spectra of Entrance and Exit Channels of Methane Molecule and Oxygen Atom Reaction at MP2 Theory
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     IR spectra of entrance and exit channels of methane and radical oxygen reaction are predicted in the ground state energy. Ab initio calculations at perturbation theory (MP2) with Dunning correction- consistent basis set (aug-cc-pVDZ) have been used. The calculations predicted structures, vibrational frequencies and potential energy surface. Three van der Waals minima from three adiabatic potential energy surfaces have been predicted in entrance and exit channels. Vibration frequency of 3209 cm-1 and 3212 cm-1 of C-H stretching in entrance structures are predicted while O-H vibrational frequency is predicted to be at 3673 cm-1 in the other channel. The lowest energy structure in entrance

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Publication Date
Mon May 01 2023
Journal Name
Journal Of Engineering
Experimental Investigation of Heat Transfer Enhancement in a Double Pipe Heat Exchanger Using Compound Technique of Transverse Vibration and Inclination Angle
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Numerous tests are recently conducted to assess vibration's role in accelerating the heat transfer rate in various heat exchangers. In this work, the enhancement of heat transfer by the effect of transfer vibration and inclination angles on the surface of a double pipe heat exchanger experimentally has been investigated. A data acquisition system is applied to record the data of temperatures, flow rates, and frequencies over the tests. A compound technique was adopted, including the application of a set of inclination angles of (0°, 10°, 20°, and 30°) under the effect of frequency of vibration ranging from sub-resonance to over-resonance frequencies. The results showed that the overall heat transfer coefficient enhan

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Publication Date
Thu Mar 30 2023
Journal Name
Iraqi Journal Of Science
Characterization of Laser induced cadmium plasma in air
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In this paper, the fundamental harmonic of a Nd:YAG laser (Q-switched 1064nm wavelength, 1 Hz repetition rate and 9 ns pulse duration) has been used for the ablation of cadmium samples in air at atmospheric pressure and the generation of the cadmium plasma. The experimentally observed lines of cadmium plasma emission have been used to calculate the plasma parameters such as (electron temperature (TReR), electron density (nReR), Debye length (λRDR) and plasma frequency (ωRpR)). Line pair ratio of neutral species have been used for the electron temperature and electron density measurements. Plasma parameters were studied as a functions of laser pulse energy.

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Publication Date
Fri Jan 01 2021
Journal Name
Environment Asia 14(1) 2021 13-22
Synoptic analysis of dust storm in Iraq
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In this study, the synoptic analysis of dust storm for spring and summertime in Iraq were investigated. The images for dust provided by NASA are used to emphasize the dust storm days, while the composite maps of wind vector and geopotential 850hPa are mapped to investigate the pressure and wind direction patterns appearing with the dust condition in the same days. Spring has more dust frequency than summertime, especially in May. The frontal type of dust storm is dominant on spring, the cold air pushes the warm air that picking up the sand to the air through the vertical wind, but the southwestern high-speed wind and drought condition were controlled on the dust in summer. The northwestern wind is the main factor that carries the dust for l

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Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
The Effect of Tool Path Strategy on Mechanical Properties of Brass (65-35) in Single Point Incremental Sheet Metal Forming (SPIF)
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In this paper, three tool paths strategies; iso-planar, helical and adaptive have been implemented to investigates their effect on the mechanical properties of Brass 65-35 formed by single point incremental sheet metal forming process. To response this task, a fully digital integrated system from CAD modeling to finished part (CAD/CAM) for SPIF process has been developed in this paper.
The photo-micrographs shows an identical grain formation due to the plastic deformation of the incremental forming process, change in the grain shape and size was observed. It's found that the adaptive tool path play a significant role to increase the hardness of the formed specimen from (48 to 90 HV) and the grain texture of the formed specimen found a

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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
Dispersion Parameters of Thermally Deposited Thin Lithium Floride Films at Different Annealing Temperatures
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Thin Lithium Fluoride films have been prepared by thermal evaporation technique on glass substrate under vacuum of about 10-5mbar. The thickness of the films was 4000±50Å. The effects of annealing temperatures on the optical properties and dispersion parameters have been studies. Transmittance spectra of the films indicate that the films have high transparency. The optical absorption studies reveal that the transition is direct with band gap value varied with the annealing temperatures. Also the refractive index dispersion curves obey to the single oscillator's model. The dispersion energy and single-oscillator energy varied with the annealing temperatures

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Publication Date
Sun Jan 13 2019
Journal Name
Iraqi Journal Of Physics
Quantum mechanical study of electronic properties of zigzag nanotubes (9,0) (SWCNTs)
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Quantum calculations on the most stable structure were carried
out for calculating the electronic properties, energies and the charge
density at the Carbon and Hydrogen atoms by Semi-empirical
method (PM3) of zigzag carbon nano tube CNT (9,0) (SWCNTs), at
the equilibrium geometry depending on the pictures of Zigzag
CNT(9,0) which was found to has D3d symmetry point group by
applying for (Gaussian 2003) program. In this work the results
include calculation the relation for axial bonds length, which are the
vertical C-C bonds (annular bonds) in the rings and bonds length
which are in the outer ring that called the circumferential bonds. Also
include a different kind of vibration modes like breathing, puckering

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