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Microwave losses of nanostructure Li-Ni ferrites in X-band and Ku-band

The molar ratio(x) of Li-Ni ferrites in the formula Li0.5-0.5xNixFe2.5-
0.5xO4 was varied in range 0.1-1.0 by hydrothermal process. The
XRD, SEM, and TEM tests were conducted to examine the samples
crystalline phase and to characterize the particles shapes and sizes.
The high purity spinel structure was obtained at med and high x
values. SEM and TEM images showed the existence of different
ferrite particles shapes like nanospheres and nanorods. The
maximum particle size is around (20nm). These size encourage
occurrence of super paramagnetic state. The reflection loss and
insertion loss as microwave losses of Li-Ni ferrite-epoxy composite
of 1mm thickness and mixing ratio 39.4 wt was investigated. The
minimum reflection loss in x-band and in Ku band was about -8dB
around 10GHz and lower than -18dB respectively. The insertion loss
exceeded -6dB in the two band for some samples.

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Comments on Properties of Gas Rich Dwarfs Galaxies in the Range of Radio Frequencies (B-Band)

    In this project we analyze data of a large sample of gas rich dwarfs galaxies including; Low Surface Brightness Galaxies (LSBGs), Blue Compact Galaxies (BCGs), and dwarfs Irregulars (dIr). We then study the difference between properties of these galaxies in the range of radio frequencies (B-band).       The data are available in HIPASS catalogue and McGaugh’s Data Page.  We depended also NASA/IPACExtragalactic Databes web site http://ned.ipac.caltech.edu in the data reduction.       We measured the gas evolution (HI mass), gas mass-to-luminosity ratio, and abundance of the elements such as the oxygen abundance for these galaxies. Our results show a

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Publication Date
Sun Jan 01 2017
Ultra low power and highly linearized LNA for V-band RF applications in 180 nm CMOS technology

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Publication Date
Thu Jun 30 2022
Journal Name
Iraqi Journal Of Laser
PDF Towards C+L Band Three-Mode (De)Multiplexer Using Subwavelength Grating (SWG) Technology

Abstract: Recently, there is increasing interest in using mode-division multipelexing (MDM) technique  to enhace  data rate transmission over multimode fibers.  In this technique, each fiber mode is treated as a separate optical carrier to transfer its own data.  This paper presents a broadband, compact, and low loss three-mode (de)multiplexer designed for C+L band using subwavelength grating (SWG) technology and built-in silicon-on-insulator SOI platform. SWG offers refractive index engineering for wider operating bandwidth and compact devices compared to conventional ones. The designed (de)multiplex deals with three modes (TE0, TE1, and TE2) and has a loss > -1 dB and crosstalk < −15 dB, and its operation c

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Publication Date
Tue Oct 01 2013
Journal Name
Proceedings Of The International Astronomical Union
The infrared <i>K</i>-band identification of the DSO/G2 source from VLT and Keck data
Abstract<p>A fast moving infrared excess source (G2) which is widely interpreted as a core-less gas and dust cloud approaches Sagittarius A* (Sgr A*) on a presumably elliptical orbit. VLT <italic>K<sub>s</sub></italic>-band and Keck <italic>K</italic>′-band data result in clear continuum identifications and proper motions of this ∼19<sup><italic>m</italic></sup> Dusty S-cluster Object (DSO). In 2002-2007 it is confused with the star S63, but free of confusion again since 2007. Its near-infrared (NIR) colors and a comparison to other sources in the field speak in favor of the DSO being an IR excess star with photospheric continuum emission at 2 microns than a</p> ... Show More
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Publication Date
Thu Jun 01 2023
Journal Name
Iraqi Journal Of Physics
Design and Analysis of the Hexagonal-Shaped Antenna with Multi-Band Feature for WLAN, WiMAX, and LTE Applications

Developing and researching antenna designs are analogous to excavating in an undiscovered mine. This paper proposes a multi-band antenna with a new hexagonal ring shape, theoretically designed, developed, and analyzed using a CST before being manufactured. The antenna has undergone six changes to provide the best performance. The results of the surface current distribution and the electric field distribution on the surface of the hexagonal patch were theoretically analyzed and studied. The sequential approach taken to determine the most effective design is logical, and prevents deviation from the work direction. After comparing the six theoretical results, the fifth model proved to be the best for making a prototype. Measured results rep

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Publication Date
Sun Sep 03 2017
Journal Name
Baghdad Science Journal
Calculation of Lambda Doubling for 7LiH1 molecule Using the System band emission for electronic transmissions

The A2?u-X1?g+ emission band system of 7LiH1 molecule has been calculated for Lambda doubling. The relation between wave number ?p , ?Q , ?R conducted the energies of the state of rotation F (J), and (J + 1) with rotational quantum number J, respectively, of 7LiH1 molecule for statehood A2?u using the rotation, fixed vibrational states of both the ground and raised crossovers vibrational against ???= 0 to V ' = 0-4using rotational levels J = 0 to J = 20 have found.

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Publication Date
Mon Feb 01 2021
Journal Name
Journal Of Engineering
Design narrow-band frequency amplifier (1.5GHz -1.6GHz) based on InGaP Heterojunction Bipolar Transistor (HBT) and GaAs HBT

The research aims to design a narrow-band frequency drive amplifier (1.5GHz -1.6GHz), which is used to boost the transmitter amplifier's input signal or amplify the GPS, GlONASS signals at the L1 band.

The Power Amplifier printed circuit board (PCB) prototype was designed using InGaP HBT homogeneous technology transistor and GaAs Heterojunction Bipolar Transistor (HBT) transistor. Two models have been compared; one of the models gave 16dB gain, and the other gave 23dB when using an input power signal (-15dBm). The PCB consumes 2.4W of power and has a physical dimension of 11 x 4 cm.

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Laser
Design and Implementation Tunable Band Pass Filter based on PCF-Air Micro-cavity FBG Fabry-Perot Resonator

A tunable band pass filter based on fiber Bragg grating sensor using an in-fiber Mach-Zender interferometer with dual micro-cavities is presented. The micro-cavity was formed by splicing together a conventional single-mode fiber and a solid core photonic crystal fiber (SCPCF) with simple arc discharge technique. Different parameters such as arc power, length of the SCPCF and the overlap gap between samples were considered to control the fabrication process. The ellipsoidal air-cavity between the two fibers forms Fabry-Perot cavity. The diffraction loss was very low due to short cavity length. Ellipsoidal shape micro-cavities were experimentally achieved parallel to the propagation axis having dimensions of (24.92 – 62.32) μm of width

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Publication Date
Sun Sep 06 2009
Journal Name
Baghdad Science Journal
Band Gap Energy for SiC Thin Films Prepared By TEACO2 Laser Irradiated With Nuclear Radiation

The effect of high energy radiation on the energy gap of compound semiconductor Silicon Carbide (SiC) are viewed. Emphasis is placed on those effects which can be interpreted in terms of energy levels. The goal is to develop semiconductors operating at high temperature with low energy gaps by induced permanent damage in SiC irradiated by gamma source. TEACO2 laser used for producing SiC thin films. Spectrophotometer lambda - UV, Visible instrument is used to determine energy gap (Eg). Co-60, Cs-137, and Sr-90 are used to irradiate SiC samples for different time of irradiation. Possible interpretation of the changing in Eg values as the time of irradiation change is discussed

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Study The effect of central ion to the dithene complexes on spectral shifting of saturable absorber band

In this work dithine complexes prepared from dithiol benzil ligand and central ion to the Ni,Pd,Pt, element the ligand and complexes have been investigated using FTIR spectrophotometer and uv-vis-NIR spectral reigns show higher intensity represents the ?-?* transition in the chromopher cycle .These absorption which appear in visible and near IR spectral regions ,According to the complexes of one group ,the spectral shifting due to the change of central ion has been found to be related to atomic number of central ion .This shifting is increased while decreasing the central ion atom number These complexes have been implemented in Nd+2:YAG cavity because each posses resonant absorption band near Nd+2:YAG, Nd+2:Glass emitting at (106

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