ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY
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Assessment the Natural Radioactivity of Radionuclides ( 226Ra, 232Th, 40K, and 137Cs) in Wheat Grain
Get PDFThis paper investigates the activity concentration of radionuclides (226Ra, 232Th, 40K and 137Cs) in the wheat grain samples using a high-purity germanium detector. Thirty-six wheat grain samples were collected from different locations of Koya City, Iraqi Kurdistan region. Average activity concentrations of 226Ra, 232Th and 40K in wheat grain are found to be 0.407 ± 0.097 Bq.kg-1 for 226Ra, 0.36 ± 0.14 Bq.kg-1 for 232Th and 109.25± 2.214 Bq.kg-1 for 40K, respectively. The measured activity concentrations for the radionuclides are compared with the reported data from other countries. In addition, the fallout radionuclide of 137Cs has no detection of in the wheat grain samples. The radium equivalent activity Raeq, internal and external hazard indices Hin and Hex, and annual gonadal dose equivalent are calculated for the measured samples. The total ingestion dose is 113.19 µSv.y-1, which is below the world average value of 290 µSv.y-1
Preparation and Characterization of Green Fe3 O4 Nanoparticle Using the Aqueous Plant Extract of Gundelia tournefortii L.
Get PDFIn 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
Withania Somnifera: Correlation of Phytoconstituents with Hypolipidemic and Cardioprotective Activities
Get PDFWithania somnifera (WS) (Dunal) or Ashwagandha is a well-known hypolipidemic herb and antioxidant. In this study, 75% ethanolic extract of WS is attempted to evaluate the cardioprotective activity of isoproterenol-induced cardiotoxicity and hypolipidemic activity in Triton WR 1339-induced hyperlipidemia. In addition, phytochemical evaluation of the same extracts analyzed by gas chromatography–mass spectrometer (GC–MS). This study found that 7 days of therapy with WS extracts at 1000 mg/kg b.wt. reduced cholesterol by 76%, low-density lipoprotein (LDL) by 71%, and TAG by 12% (P < 0.05). Furthermore, it can significantly reduce cholesterol and LDL levels (P < 0.05). Similarly, the use of 50 mg/kg b.wt. of WS extract showed a cardioprotective effect against isoproterenol-induced cardiac toxic rats. The antioxidants glutathione, glutathione peroxidase, and catalase are increased in WS extract (P < 0.05), whereas the release of cardiac indicators in heart tissue is reduced (P < 0.05). Furthermore, a 30-day treatment with WS also reduced triacylglycerol in isoprenaline-induced cardiotoxic rats. GC–MS analysis of the methanol fraction of the Ashwagandha 70% ethanolic extract showed the presence of higher concentrations of fatty acids. In conclusion, WS showed hypolipidemic and cardioprotective activities in diseased animals induced by isoproterenol and Triton WR 1339
Corrosion in Crude Oil Distillation Unit Overhead: A recent Case Study
Get PDFDespite all the technological advances and the control mechanisms that exist today to achieve the control of corrosion in overhead systems in atmospheric crude oil distillation units, there is still a high level of difficulty in predicting the phenomenon due to the complexity of the chemical compounds involved in the entire process. The study of this practical case aims to determine what control mechanisms should be optimized in a refinery located in the Autonomous Region of Iraqi Kurdistan to prevent corrosion phenomena’s in this specific system and how it should be done to achieve these improvements. It has been suggested that the corrosion mechanisms by hydrochloric acid and by ammonium chloride have been those that have acted in the operational context of the mentioned facility. To test this hypothesis, a study of the unit’s operational conditions and analytical tests were carried out on the construction material of various components and the products (sediments) found inside the tower. The results show that a lack of control in the salts and sediments content of the feed crude have caused an increase in the hydrolysis process of certain components upstream of the tower and thus the generation of acids and salts was promoted. On this basis, it is necessary to optimize the primary treatment of crude oil and update the chemical treatments and washing water systems to adapt to the new conditions of the feed of the refinery
Determination of Multi-performance Characteristics in Electric Discharge Machining of DIN 1.2767 Steel Using Grey Relational Analysis
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Electric discharge machining (EDM) is one of the most important unconventional machining processes, which can cut hard materials and complex shapes that are difficult to machine by conventional machining processes easily and with high accuracy. In this study, L18 orthogonal array combined with gray relational analysis (GRA) is implemented to investigate the multiple performances characteristics in EDM of DIN 1.2767 Tool Steel. Machining process parameters selected were discharge current (Ip), pulse-on time (Ton), pulse-off time (Toff), and electrode material (copper alloys [NSS and B2]). The investigated performances characteristics were tool wear rate (TWR) and material removal rate (MRR). Analysis of variance (ANOVA) and Taguchi’s signal-to-noise ratio with the help of Minitab-17 software were used to analysis the effect of the process parameters on TWR and MRR. The experimental results and data analysis reveal that TWR and MRR are more affected by Ip and Ton. The minimum TWR was obtained at parametric combination Ip (6A), Ton (800 μs), and Toff (800 μs) and the maximum MRR attained at Ip (25A), Ton (800 μs), Toff (200 μs), and NSS electrode. After applying GRA, the optimal parametric combination for MRR and TWR was determined as Ip (25A), Ton (800 μs), Toff (200 μs), and NSS electrode. The study also exhibited the occurrence of an interaction between the variables on the responses. In addition, scanning electron microscopy images showed that the metal surface was affected with the increase in Ton and Toff
A Study on the Prevalence and Source of Staphylococci and Methicillin-resistant Staphylococcus aureus Causing Superficial Incisional Surgical Site Infection
Get PDFStaphylococcus aureus and coagulase-negative staphylococci (CoNS) are common causatives of superficial incisional surgical site infection (SSI). The source of the pathogens is still not fully diagnosed whether it is endogenous or exogenous particularly with regard to the extent of its resistance to antibiotics. Therefore, this study is designed to determine the rate of infection, the source of pathogens, and the extent of their resistance to antibiotics. For this purpose, pre-, intra- and post-operative swabs from the nasal and skin of patients undergoing surgeries and samples from the hospital environment have been collected and processed for isolation and identification of staphylococci. Bacterial analysis and antibiotic susceptibility profiles of the isolates are assessed by unweighted pair group method with arithmetic mean (UPGMA) analysis based on random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) and disc diffusion test for antibiotics susceptibility profile. The microbiological and PCR results indicate that SSIs are found in 113/512 (22.07%), Staphylococcus spp. rated 67/512 (13.09%) of infections. Further analysis indicates that S. aureus, CoNS, and both of them were causes SSI with different rates 41/67 (61.2%), 23/67 (34.3%), and 3/67 (4.5%), respectively. Results of RAPD-PCR for 70 isolates reveal that 52/70 (74.28%) of SSIs are from endogenous source, followed by 10/70 (14.29%) and 8/70 (11.43%) from hospitals acquired and undetermined sources, respectively. Moreover, results of antibiotic susceptibility test reveal that 24/44 (54.5%) of isolates belong to methicillin-resistant Staphylococcus aureus; from both endogenous and exogenous sources with 13/24 (54.17%) and 11/24 (45.83%), respectively
Evaluation of Flying Ad Hoc Network Topologies, Mobility Models, and IEEE Standards for Different Video Applications
Get PDFNowadays, drones became very popular with the enhancement of the technological progress of moving devices with a connection to each other, known as Flying Ad Hoc Network (FANET). It is used in most worldwide necessary life scenarios such as video recording, search and rescue, military missions, moving items between different areas, and many more. This leads to the necessity to evaluate different network strategies between these flying drones, which are essential to improve their quality of performance in the field. Several challenges must be addressed to effectively use FANET, to provide stable and reliable transmission for different types of data during vast changing topologies, such as different video sizes, different types of mobility models, recent Wireless Fidelity standards, types of routing protocols used, security problems, and many more. In this paper, a fully comprehensive analysis of FANET will be done to evaluate and enhance these challenges that concern different video types, mobility models, and IEEE 802.11n standards for best performance, by measuring throughput, retransmission attempt, and delay metrics. The result shows that Gauss–Markov mobility model gives the highest result using Ad Hoc On-Demand Vector and lowest delay, whereas for retransmission attempts, 2.4 GHz frequency has the lowest as it can reach more coverage area than 5 GHz
Design and Analysis of a Wide Stopband Microstrip Dual-band Bandpass Filter
Get PDFA 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
Assessment of the Upstream Slope Stability of Darbandikhan Rockfill Dam during Drawdown
Get PDFEarth and rockfill dams face a variety of loading conditions during lifetime. One of the most critical loading conditions is the rapid drawdown of water level after steady state conditions. Rapid drawdown may cause instability of upstream slope of the dam. The present work examines the stability of a rockfill dam under different drawdown rates in terms of factor of safety for the upstream slope of the dam. For this purpose, a computer software named GeoStudio 2012 SEEP/W and SLOPE/W has been used for the numerical analysis. The results showed that the drawdown rate has a significant effect on stability of rockfill dam in which increasing the drawdown rate from 1 m/day to 10 m/day decreases the stability of the dam by 33%. Based on the outcomes, for the studied case the drawdown rate (1 m/day) can be recommended
Structural Behavior of Reinforced Concrete Beams Incorporating Foamed Glass as Aggregates
Get PDFNatural resources that are utilized in civil engineering applications can be saved by replacing them with some recycled materials to produce sustainable concrete with required mechanical and durability properties. In recent years, recycled glass is being used as aggregates in concrete production in many countries across the world. In the present study, the structural properties of reinforced concrete beams containing foamed glass (FG) as a partial natural coarse aggregate replacement are investigated. Five concrete mixes were employed to conduct the present study. The coarse aggregate was replaced with 0%, 25%, 50%, 75%, and 100% (by volume) of FG. Four point-loading flexural tests on beams were conducted up to failure. The results showed that the compressive strength was decreasing linearly with the increasing amount of FG. It was also observed that the ductility of the reinforced concrete beams significantly improved. However, the load-carrying capacity of the beam and load at which the first crack occurs was reduced. It was concluded that the inclusion of FG in structural concrete applications is possible and the structural behavior of concrete beams proved to be similar to that of other types of lightweight aggregate concrete such as wood and plastic aggregates used in similar structural elements