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A New Fractal Printed Dipole Antenna Based on Tent Transformations for Wireless Communication Applications
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In this paper, a compact multiband printed dipole antenna is presented as a candidate for use in wireless communication applications. The proposed fractal antenna design is based on the second level tent transformation. The space-filling property of this fractal geometry permits producing longer lengths in a more compact size. Theoretical performance of this antenna has been calculated using the commercially available software IE3D from Zeland Software Inc. This electromagnetic simulator is based on the method of moments (MoM). The proposed dipole antenna has been found to possess a considerable size reduction compared with the conventional printed or wire dipole antenna designed at the same design frequency and using the same substrate specifications. Results have shown that the proposed design possesses a multi-band resonant behavior with adequate radiation performance with VSWR ≤ 2 (return loss ≤-10 dB) throughout the resonating bands. This makes the presented antenna (or its monopole counterpart) suitable for use in the modern multi-functions compact communication systems. 

              

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Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Biochemical and Kinetic Study on Serum Adenosine Deaminase Enzyme in P­ Thalassaemia
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This study was conducted to investigate activity and some kinetic

and  thermodynamic  parameters  of  adenosine  deaminnse  (ADA)in

serum in patient affected with P-thalassaemia and compared with that of   healthy   individuals    .Serum   AD   levels   were   found   to   be significantly  higher  in  patient  with  P-thalassaemia  (98±9.15  IU/L) than in healthy  individuals (22± 2.04 IUIL)the study was carried in optimum pH value 6.5 and 37c  by which the enzyme possess highest activity .The study was concentrated to comprehensive  determina

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Publication Date
Sun Feb 10 2019
Journal Name
Iraqi Journal Of Physics
The effect of thickness on the optical properties of Cu2S thin films
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In this work, the optical properties of Cu2S with different thickness
(1400, 2400, 4400) Ǻ have been prepared by chemical spray pyrolys
is method onto clean glass substrate heated at 283 oC ±2. The effect
of thickness on the optical properties of Cu2S has been studied. It
was found that the optical properties of the electronic transitions on
fundamental absorption edge were direct allowed and the value of the
optical energy gap of Cu2S (Eg) for direct transition decreased from
(2.4-2.1) eV with increasing of the thickness from (1400 - 4400)Ǻ
respectively. Also it was found that the absorption coefficient is
increased with increasing of thicknesses. The optical constants such<

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Publication Date
Sun Apr 30 2017
Journal Name
Journal Of Engineering
Influence of Internal Sulfate Attack on Some Properties of Self Compacted Concrete
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      Self-compacted concrete (SCC) is a highly flowable concrete, with no segregation which can be spread into place by filling the structures framework and permeate the reinforcement without any compaction or mechanical consolidation ACI 237R-14. One of the most important problems faced by concrete industry in Iraq and Gulf Arab land is deterioration due to internal sulfate attack (ISA) that causes damage of concrete and consequently reduces its compressive strength, increases expansion and may lead to its cracking and destruction. The experimental program was focused to study two ordinary Portland cements with different chemical composition with (5, 10 and 15) % percentage of high reactivity metakaoline (HRM)

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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
Community Structure of South Sudan state and its impact on national integration
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South Sudan is known by its tribal and racial variation .Tribal Perception represents the
procedure of dealings in Southern society .And that what make Sudan as a stable country that
suffer from divisions . Everybody wants to rule in spite of his inability and un qualification
which enables the establishment of an urbanized country .the frustration of the state in
handling the interior variety on religious, tribal and racial basis and contracting national
ideality in spared by shared ingredients between gathered groups in one state, all these reasons
make it hard to create a united national identity which is able to unite atheist and religious
parties together. Due to this ,the study is established to clarify the nat

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The effects of raddiation on the optical properties of GERMANIUM SELENIDE semiconductor.
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Study was made on the optical properties of Ge2oSe8othinfilms prepared by vac-uum evaporation as radiated by (0,34,69) Gy of 13 ray.The optical band gab Eg and tailing band A.Et were studied in the photon energy range ( 1 to 3)eV. The a-Ge20Se8o film was found to be indirect gap with energy gap of (1.965,1.9 , 1.82) eV at radiated by B ray with absorption doses of (0,34,69)Gy respectively.The Ea and AEt of Ge20Se80 films showed adecrease in E8 and an increase in AEt with radiation. This be-havior may be related to structural defects and dangling bonds.

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Publication Date
Mon Jun 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Effect of Ageing on Physical and Chemical Properties of Asphalt Cement
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Two grades of paving asphalt with penetration of 46 and 65 are studied for determining changes in their physical and chemical properties caused by ageing.
The ageing process has been conducted on two petroleum paving asphalt cement using thin film oven test at 150, 163 and 175 C, and ageing time 5, 10,15, 20, 25 and 30 hours. The effect of ageing time and temperature on penetration, kinematic viscosity, softening point, solubility in trichloroethylene, heat loss and changes in chemical composition are investigated. The results of thin film oven test process indicte that the asphaltenes concentration of all aged asphalt increases with increasing ageing time, while the opposite was observed for polar-aromatic and naphthene-aromatic. The

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Publication Date
Wed Sep 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Asthma and Inhaled Corticosteroid Effect on the Dental Arch Morphology in Children
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Background: asthma has an influence on craniofacial development. Recently evidences show that there is an association between oral health problems and chronic lung disease. The present study was designed to estimate the changes in arch dimension measurements among asthmatic children aged 12 years old who were collected from AL- Zahra Center Advisory for Allergy and Asthma and compare them with the non-asthmatic children of the same age and gender. Material and Methods: Fifty children (25 asthmatic and 25 non- asthmatic children) were included for the odontometric measurement. For both upper and lower study models, photographs were taken using special photographic apparatus for each child, and the statistical analysis were done by using SPSS

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Publication Date
Sat Mar 18 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Drought Stress on Barley ( Hordeum vulgare L.) in Germination Stage
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The Present study was aimed to evaluate the responses of sixteen species of barley Hordeum vulgar L. cultivated in Iraq against drought stress through treatments of seedling with varying concentrations of Polyethylene glycol (PEG6000) to reach the water stress(-3,-6,-9) in addition to control (without PEG 6000). The results showed variation of barley species in their ability to tolerate the drought stress. For instance, Boraq and Arefat were shown to be the most tolerable species, since  their percentage of seeds germination were non significantly affected by the highest water potential (-9)  bar, while (bawadi,amal,nor alqadsea and nomar) were shown to be moderately drought tolerable, since their percentage of  seeds germ

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Publication Date
Sun Dec 03 2017
Journal Name
Baghdad Science Journal
Effect of the Silver Nanoparticles on the Histology of Albino Mice Ovaries
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The aim of study is to identify the histological changes in ovaries of the albino mice exposed to silver nanoparticles. Sixty adult females were collected and exposures by 4000 p.p.m. and 50-150 nm in size, Females were divided into 3treated groups. The concentration dosage was (1, 1.5 and 2) p.p.m. of silver nanoparticles for 7, 14 and 21 days as exposure periods as well as control group which treated by normal saline. Treated groups appeared different histopathological changes, it is depending on the concentration of silver nanoparticles and the period of exposure. These changes were included congestion in the blood vessels, hemorrhage, hyaline degeneration, fatty degeneration, pyknosis, necrosis as well as fusion of cells in follicula

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Modeling of the Effect of MgO and ZrO2 on Sintering of Alumina
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  This research  studyies the effect of MgO and ZrO2 as additives in sintering Al2O3 . The experimental results are modeled using ( L2 _ regression) technique , sintered density and grain size rate measurments were  accounted by utilizing experimental results of undoped , MgO doped and ZrO2  doped alumina impregrated with spherical large pores in final stage of sintering . The effect of each additive is inhibitian of the grain growth and increasing the densification rate which enhances the kinietics of densification and the removal of large and small pores.

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