ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY
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The Effects of Amine Type and Lean Amine Temperature on Gas Sweetening Processes: A Case Study and Simulation
Get PDFIn the North Gas Company (NGC) in Kirkuk, Iraq, sour gas stream is loaded with considerable amounts of H2S and CO2 of 2.95% and 2.54%, respectively. A DEA amine system is currently used to reduce these sour component concentrations below 5 ppm and 2% for H2S and CO2, respectively. This study used Bryan Research and Engineering’s ProMax® process simulation software to optimize this amine sweetening system by adopting other amine types and blends, such as methyldiethanolamine (MDEA). It could be argued that a 50 wt% MDEA solution circulated at 414 m3/h was determined to be the optimum operating conditions. This design met sweet gas specifications and minimized the reboiler duty to 38 MW, 30.9% reduction in steam consumption. The experimental simulation work is also examined the effects of lean solvent temperature on the gas sweetening process efficiency and performance and find out that the lean amine temperature within the range of 43–48°C in all sceneries give acceptable sweetening results
Land Surface Temperature Anomalies Detection for the Strong Earthquakes in 2018
Get PDFEarthquake every year leads to human and material losses and unpredictability of it by now makes this natural disaster worsen. The objective of the current study was to determine the anomalies in land surface temperature (LST) in areas affected by earthquakes. In this research, three earthquakes (M >6) were studied. Moderate Resolution Imaging Spectroradiometer Aqua and Terra day and night LST data used from 2003 to 2018. The interquartile range (IQR) and mean ± 2σ methods utilized to select anomalies. As a result, based on the IQR method, no prior and after anomaly detected in selected cases and data. Based on mean ± 2σ, usually positive anomaly occurred during daytime. However, negative (or positive) anomaly occurred during the nighttime before the Mexico and Bolivia earthquakes. During 10 days after the earthquake, sometimes a negative anomaly detected
Mechanical Response of PbSSe, PbSTe Ternary and PbSnSTe Quaternary Alloys at High Pressure
Get PDFProperty of the semiconductors under high pressure is investigated by the density functional theory and paralleled to the foretelling of the linear elasticity theory. In addition, ternary alloys of PbSxSe1-x and PbSxTe1-x lattice matching PbS substrate for x = 0.5 compositions are studied. Furthermore, quaternary alloys PbxSn1-xSyTe1-y lattice matching PbS substrate for x and y = 0.5 compositions are studied. The six independent elastic parameters (Cij) are also calculated. Meanwhile, the results data are analyzed in high pressure. The mechanical response of all alloys to pressures 0, 50, and 100 kbar increases progress to decrease in (Cij) in separate rates. The rapprochement between the calculated results and the available published data for these alloys demonstrate that they had worthy accordance at zero pressure and the results at high pressure may be required as an acceptable reference
New Fluorescence Quenching Approach for Determination of Valsartan in Certain Tablets and Spiked Biological Fluids
Get PDFA new, simple, selective, sensitive, fast, economical, and reliable fluorescence quenching method for the quantitation of valsartan was investigated using basic fuchsin act as a fluorometric dye. The method was depended on the detection quenching influence of valsartan on the fluorescence intensity of basic fuchsin and the reaction between valsartan and basic fuchsin in a McIlvaine buffer medium at pH = 6 to yield a new basic fuchsin–valsartan non-fluorescent complex. The excitation and emission of basic fuchsin fluorescence signal were identified at 535 and 728 nm, respectively. A fluorescence quenching value (ΔF) displayed a very good linear relationship (R2 = 0.9992) with valsartan concentration ranging from 0.003 to 3 μg/mL, a detection limit as low as 0.0009 μg/mL with a high precision and accuracy (RSD% <3). Significantly, no interference effect was found due to the presence of other ingredients commonly found in medical formulations. The acquired data were statistically compared with those acquired from reported chromatographic method and were observed to be in excellent agreement at a 95% confidence level; the planned fluorescence quenching procedure was subsequently utilized to detected the concentration of valsartan in spiked biological fluids and commercial medical tablets
Evaluation of Oxidative Stress and some Biochemical Parameters in Normal Pregnant Women
Get PDFPregnancy is associated with many metabolic changes in normal pregnant woman, this leads to change in physiological, biochemical, and hematological parameters drastically. The test subjects were selected among those attending to Maternity Teaching Hospital in Erbil Governorate between March 2017 and August 2017. Four groups of individuals were included in this study, 230 pregnant women divided into three groups (Group 1 first trimester, Group 2 second trimester, and Group 3 third trimester) and Group 4 contained 90 nonpregnant women as control. Full automatic chemical analyzer (Cobas C311, Germany) was used to determine the biochemical parameters. The EL ×800 Absorbance Microplate Reader from BioTek (USA) instruments is used to measure the activity of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) in serum. The results of this study showed a significant increase in serum albumin, glucose, total bilirubin, direct bilirubin, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatinine, urea, cholesterol, low-density lipoprotein, and MDA in pregnant women as compared to the control group, also show significant decrease in high-density lipoprotein (HDL) level, SOD activity, and CAT activity in pregnant women as compared to nonpregnant women, and nonsignificant difference in uric acid, and HDL
Potato Peels and Mixed Grasses as Raw Materials for Biofuel Production
Get PDFBiogas and fuel ethanol are renewable energy sources, can be produced from complex organic materials that are decomposed by microorganisms in the anaerobic digestion method. Potato peels (PPs) and mixed Lolium perenne and Dactylis glomerata grasses were assessed as a potential substrate for biomethanation in a batch method under mesophilic condition (35°C) and ethanol fermentation. The first approach of this work was focused on pretreatment of PPs using acidic and enzymatic hydrolysis to produce biogas and ethanol fermentation using Saccharomyces cerevisiae and Safbrew S-33. These experiments proved that enzymatic hydrolysis produced 1.2 g/L of ethanol involved 115 h of fermentation and 665 ml/h of biogas after 451 h of biomethanation, this was more than the outcomes of acidic treatment. The second approach was concentrated on ability of biogas and ethanol production from mixed grasses treated with different acid concentrations that produced 0.16 g/L ethanol over 8 days of fermentation and 500 ml/h of biogas after 13 days of methanation technique. In general, the results pointed out that PPs and combined grasses can be used as potential substrates with raw materials for biogas and ethanol production
Design of a Branch-line Microstrip Coupler Using Spirals and Step Impedance Cells for WiMAX Applications
Get PDFbranch-line microstrip coupler is designed and fabricated in this paper. The proposed coupler operates at 3 GHz, which is suitable for WiMAX applications. The designed coupler has a high performance, that is, a low phase difference of 0.49°, low insertion loss, good coupling factor, and good isolation better than −30 dB. Another advantage of the designed coupler is its novel geometrical structure based on integrating the semi-circular and step impedance cells. The design process is based on introducing and analyzing an equivalent LC model to improve impedance matching and reduce losses. To verify the design process, the designed coupler is fabricated, where a good agreement between the simulation result and measurement is achieved
Energy Optimization Using a Pump Scheduling Tool in Water Distribution Systems
Get PDFWater distribution management system is a costly practice and with the growth of population, the needs for creating more cost-effective solutions are vital. This paper presents a tool for optimization of pump operation in water systems. The pump scheduling tool (PST) is a fully dynamic tool that can handle four different types of fixed speed pump schedule representations (on and off, time control, time-length control, and simple control [water levels in tanks]). The PST has been developed using Visual Basic programming language and has a linkage between the EPANET hydraulic solver with the GANetXL optimization algorithm. It has a user-friendly interface which allows the simulation of water systems based on (1) a hydraulic model (EPANET) input file, (2) an interactive interface which can be modified by the user, and (3) a pump operation schedule generated by the optimization algorithm. It also has the interface of dynamic results which automatically visualizes generated solutions. The capabilities of the PST have been demonstrated by application to two real case studies, Anytown water distribution system (WDS) and Richmond WDS as a real one in the United Kingdom. The results show that PST is able to generate high-quality practical solutions
High Security and Capacity of Image Steganography for Hiding Human Speech Based on Spatial and Cepstral Domains
Get PDFA new technique of hiding a speech signal clip inside a digital color image is proposed in this paper to improve steganography security and loading capacity. The suggested technique of image steganography is achieved using both spatial and cepstral domains, where the Mel-frequency cepstral coefficients (MFCCs) are adopted, as very efficient features of the speech signal. The presented technique in this paper contributes to improving the image steganography features through two approaches. First is to support the hiding capacity by the usage of the extracted MFCCs features and pitches extracted from the speech signal and embed them inside the cover color image rather than directly hiding the whole samples of the digitized speech signal. Second is to improve the data security by hiding the secret data (MFCCs features) anywhere in the host image rather than directly using the least significant bits substitution of the cover image. At the recovering side, the proposed approach recovers these hidden features and using them to reconstruct the speech waveform again by inverting the steps of MFCCs extraction to recover an approximated vocal tract response and combine it with recovered pitch based excitation signal. The results show a peak signal to noise ratio of 52.4 dB of the stego-image, which reflect a very good quality and a reduction ratio of embedded data to about (6%–25%). In addition, the results show a speech reconstruction degree of about 94.24% correlation with the original speech signal
Chemical and Structural Analysis of Rocks Using X-ray Fluorescence and X-ray Diffraction Techniques
Get PDFRock examinations for mining and commercial use are a vital process to save money and time. A variety of methods and approaches have been used to analyze rocks and among them, X-ray fluorescence (XRF), and X-ray diffraction (XRD) techniques proved to be an accurate method. This research was conducted to evaluate the utility and reliability of XRF and XRD to analyze the major and trace elements of rocks as well as their crystalline structures. Results showed that XRF and XRD techniques are fast and reliable, nondestructive and non-invasive analytical tools for mineral analysis, particularly for rocks. For this purpose, the analysis of 28 samples of rocks, which collected from three different places of Kurdistan region-Iraq, is reported. These places are Haybat Sultan (HS) region in Koya city as well as TaqTaq (TA) and Garmuk (GT) district nearby Koya city. Throughout this analysis, 34 major and trace elements were detected in the rocks collected from HS region, whereas forty major and trace elements were detected in the rocks collected from TA district and GT district. In addition, it was found that the structures of these rocks were crystalline in nature. This was proved through the value of diffracted angle and it was found that the majority of these rocks are oxides. The external view (the appearance) of all collected rocks was also discussed and it was found that each rock consists of a variety of minerals which will be the reason that each rock has a specific color