ARO-The Scientific Journal of Koya University
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TOTAL DOCUMENTS

158
(FIVE YEARS 113)

H-INDEX

4
(FIVE YEARS 3)

Published By Koya University

2307-549x, 2307-549x

2021 ◽  
Vol 9 (2) ◽  
pp. 83-90
Author(s):  
Salah I. Yahya ◽  
Abbas Rezaei ◽  
Yazen A. Khaleel

A novel configuration of a dual-band bandpass filter (BPF) working as a harmonic attenuator is introduced and fabricated. The proposed filter operates at 3 GHz, for UHF and SHF applications, and 6.3 GHz, for wireless applications. The presented layout has a symmetric structure, which consists of coupled resonators. The designing of the proposed resonator is performed by introducing a new LC equivalent model of coupled lines. To verify the LC model of the coupled lines, the lumped elements are calculated. The introduced filter has a wide stopband up to 85 GHz with 28th harmonic suppression, for the first channel, and 13th harmonic suppression, for the second channel. The harmonics are attenuated using a novel structure. Also, the proposed BPF has a compact size of 0.056 λg2. Having several transmission zeros (TZs) that improve the performance of the presented BPF is another feature. The proposed dual-band BPF is fabricated and measured to verify the design method, where the measurement results confirm the simulations.


2021 ◽  
Vol 9 (2) ◽  
pp. 76-82
Author(s):  
Omar T. Mahmood

Globally, a huge quantity of alum sludge waste is produced as a by-product material from drinking water treatment plants that utilize aluminum salts as an essential coagulate and is the most generally produced water treatment remaining sludge around the world, which causes a serious environmental problem. Direct discarding of this substance has ecological effects. Hence, it is important to reuse this alum sludge waste material in such a manner to diminish its detrimental impacts on the environment. This research investigates the possibility of reusing alum sludge waste as a partial replacement of cement filler in stone mastic asphalt (SMA) paving mixtures. For this investigation, the alum sludge was used as a filler material in SMA mixtures in two modes; dried alum sludge at 110°C and burned alum sludge at 700°C. Different percentages of alum sludge were used as a replacement by the total weight of mineral filler at 0, 20, 40, 60, 80, and 100%. The results showed that using alum sludge as a substitution of filler in SMA mixtures reduces the performance of the mixtures in terms of Marshall properties and tensile strength for both dried and burned alum sludge compared with a standard mix. However, the performance of the mixtures containing burned alum sludge gave a better performance than the mixtures containing dried alum sludge.


2021 ◽  
Vol 9 (2) ◽  
pp. 71-75
Author(s):  
Akram H. Taha

Density functional theory (DFT) coupled with ) method are carried out to calculate the electronic structures of AgX (X; Br, Cl, and F). The effect of hybridizing between 4d orbital of Ag element and the p orbitals of the X in the valence band plays a very important role in the total density of states configuration. The electronic structure has been studied and all results were compared with the experimental and theoretical values. The importance of this work is that there is insufficient studies of silver halides corresponding the great importance of these compounds. Almost all the results were consistent with the previous studies mentioned here. We found the band gap of AgX to be 2.343 eV, 2.553 eV, and 1.677 eV for AgBr, AgCl, and AgF respectively which are in good agreement with the experimental results.      


2021 ◽  
Vol 9 (2) ◽  
pp. 58-63
Author(s):  
Aveen F. Jalal ◽  
Nabil A. Fakhre

In this work, the magnetite nanoparticles (Fe3O4-NPs) synthesized using a simple, fast, and environmentally acceptable green approach. Gundelia Tournefortii Extract, an aqueous plant extract, was used for the first time in green synthesis to prepare nanoparticles as reducing, capping, and stabilizing agents. Such biomolecules as flavonoids, alkaloids, and antioxidants are found in the aqueous leaf extract, and their presence has been determined to have an important role in the synthesis of Fe3O4-NPs. The techniques used in this analysis include Fourier Transform Infrared, Scanning Electron Microscopy, Energy-Dispersive X-ray spectroscopy, X-ray Diffraction, Transmission Electron Microscopy, and Vibrating Sample Magnetometer. The Vibrating Sample Magnetometer demonstrated that the samples were superparamagnetic, with a magnetization value of 48.6 emu/g. The prepared nanoparticle was applied to  remove Chrystal Violet (CV), Malachite Green(MG), and Safranin (S) dyes from prepared aqueous solutions with the adsorption capacity of 13.9, 15.6, and 14.4 mg/g respectively.


2021 ◽  
Vol 9 (2) ◽  
pp. 64-70
Author(s):  
Ahmed A. Al-Naqshbandi ◽  
Hedy A. Hassan ◽  
Mahmoud A. Chawsheen ◽  
Haval H. Abdul Qader

Wound infection with antibiotic-resistant bacteria can extend a patients’ debility and increase the expense of treatment in the long term; therefore, careful management of patients with wound infections is necessary to avoid complications. The usage of antimicrobial agent is a major factor in resistance development. This study aims to understand the causes of wound infections, as well as the criteria for diagnosing them for more sensible antibiotic prescribing. Samples from 269 wound patients were collected, and cultured for bacterial growth. Gram stain technique, bacterial identification via VITEK 2 compact system were investigated in this study. Gram negative bacteria accounted for 59.15% of the total isolates, while pathogenic gram positive bacteria accounted for 40.85% of total isolates. Escherichia coli and Pseudomonas aeruginosa are the dominant pathogenic gram negative bacteria in wounds, while Staphylococcus aureus, and Staphylococcus epidermidis are the dominant pathogenic gram positive bacteria. Pseudomonas aeruginosa showed 100% resistance to the majority of antibiotic tested, including Ampicillin, Amoxicillin/Clavulanic Acid, Aztreona, Ceftriaxone, and others. Staphylococcus aureus and Staphylococcus epidermidis are 100% resistant to Ampicillin, Ceftriaxone, and Cefotaxime. For more efficient antibiotic prescriptions, the causative microorganisms, and their current susceptibility patterns need to be mandated for testing before prescribing any antibiotics to patients. Prescriptions are frequently based solely on general information about the antibiotic's function, rather than on individual response variation to the pathogen and the antibiotic. Particularly when the common pathogens in this study show multidrug resistance in wounds.


2021 ◽  
Vol 9 (2) ◽  
pp. 51-57
Author(s):  
Safia S. I. Blbas ◽  
Hiwa A. Ahmad ◽  
Dawan J. Hawezy ◽  
Hemn Shawgery ◽  
Hersh N. Bahadin

Coronavirus is a pandemic disease. In most cases, the exact infection rate cannot be determined as not everybody can be tested for the virus, even though some of them carry the virus silently. Therefore, detection of antibodies of this virus is more practical to give us a better clue about the rate of infection because the asymptomatic people can be tested too. The serological detection of anti-Severe Acute Respiratory Syndrome-Coronavirus (SARS-COV-2) antibodies among asymptomatic and moderate symptomatic individuals gives us the vital point to understanding the prevalence rate of COVID-19 among the population. Total of (436) volunteers were participated, (96) from teaching staff, (172) employee, and (168) students. Anti-SARS-COV-2 immunoglobulin G (IgG) and Immunoglobulin M (IgM) were detected in the serum by ELISA technique, and complete blood count was performed for all participants. The number of seropositive of anti-SARS-COV-2/IgG was (159), whereas IgM was (66). The highest prevalence rate of IgG detected among participants with family member infected with coronavirus (42.7%). Total WBCs count significantly increased among IgM positive participants. Many asymptomatic people were infected with coronavirus, which lead to more spreading of the virus among the population. Therefore, mass screening of the population for specific antibody against coronavirus is important to reduce the infection rate.


2021 ◽  
Vol 9 (2) ◽  
pp. 46-50
Author(s):  
Muhanad A. Ahmed ◽  
Mohammed F. Mohammed Sabri ◽  
Wathiq R. Abed

In this paper, nanostructured silicon carbide (SiC) thin films are deposited onto glass substrate using pulsed laser deposition technique. Electrical and optical characterizations such as conductivity, resistivity, transmission, Seeback effect, absorption, absorption coefficient, energy band gap, and extinction coefficient as a function of photon energy, and the effect of thin films thickness on transmission are carried out to characterize the prepared samples. Results showed that the prepared SiC thin film is an n-type semiconductor with an indirect bandgap of ~3 eV, 448 nm cutoff wavelength, 3.4395 × 104 cm−1 absorption coefficient and 0.154 extinction coefficient. The surface morphology of the SiC thin films is studied using scanning electron microscope at a substrate temperature of 400 °C and it is found that the grain size of the prepared SiC thin film is about 30 nm. As such, the nano thin films optical and structural characteristics enable the films to be used as gases sensors in many optoelectronic devices such as the environment and ultraviolet photodiode.


2021 ◽  
Vol 9 (2) ◽  
pp. 42-45
Author(s):  
Hanaa A. Muhammad ◽  
Khalid N. Sediq ◽  
Kwestan H. Sdiq

Recently, bottled water consumption has been increasing significantly, even when the quality of tap water is considered excellent, which contributes to plastic pollution. Besides, reducing the use of plastic generally is recommended world widely, as its consumption is in an alarming rate. Therefore, this study aims to compare the tap and bottled water and manifest the reasons behind choosing the bottled water, which is less comfortable and often more expensive over the tap water. In this study, samples have been taken from both bottled and tap water in Koya city from November 2020 to May 2021 to test their quality using PH, DO, EC, and TDS meter, hardness was determined by complexometric titration method at 21°C, and XRF spectrometers. According to the quality standards, most of the variables were in a permissible range, except for dissolved oxygen and Aluminum content in both types of water and TDS for two types of bottled water. However, the quality of tap water was much safer to be used, as compared with the bottled water. 


2021 ◽  
Vol 9 (2) ◽  
pp. 38-41
Author(s):  
Khalid N. Sediq

Two-dimensional photonic crystal nanocavities were designed to tailor cavity quantum electrodynamics. Enhancing the spontaneous emission of low-quality factor nanocavity with embedded CdSe quantum dots (QDs) emitters is the aim of this study. Low concentration layer of CdSe QDs was sandwiched between two layers of Si2 N3 membrane using plasma-enhanced chemical vapor deposition. The modification rate in spontaneous emission of L3 nanocavity up to 2.3-fold has been observed at 629.5 nm in compare to bare cavities. High field confinement in the sub-wavelength regime became an interest field for quantum electrodynamics applications and good platform to study light matter interactions.


2021 ◽  
Vol 9 (2) ◽  
pp. 30-37
Author(s):  
Nahla Aljojo

While Big Data analytics can provide a variety of benefits, processing heterogeneous data comes with its own set of limitations. A transaction pattern must be studied independently while working with Bitcoin data, this study examines twitter data related to Bitcoin and investigate communications pattern on bitcoin transactional tweet. Using the hashtags #Bitcoin or #BTC on Twitter, a vast amount of data was gathered, which was mined to uncover a pattern that everyone either (speculators, teaches, or the stakeholders) uses on Twitter to discuss Bitcoin transactions. This aim is to determine the direction of Bitcoin transaction tweets based on historical data. As a result, this research proposes using Big Data analytics to track Bitcoin transaction communications in tweets in order to discover a pattern. Hadoop platform MapReduce was used. The finding indicate that In the map step of the procedure, Hadoop's tokenize the dataset and parse them to the mapper where thirteen patterns were established and reduced to three patterns using the attributes previously stored data in the Hadoop context, one of which is the Emoji data that was left out in previous research discussions, but the text is only one piece of the puzzle on bitcoin transaction interaction, and the key part of it is “No certainty, only possibilities” in Bitcoin transactions


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