ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY
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The Study of Optical Energy Gap, Refractive Index, and Dielectric Constant of Pure and Doped Polyaniline with HCl and H2SO4 Acids
Get PDFPolyaniline (PANI) salt in its pure and doped forms find extensive applications in making devices such as polymer light emitting diodes, photovoltaic, sensors, batteries, and super capacitors. PANI salt has been synthesized successfully through chemically oxidative polymerization of aniline in the presence of hydrochloric acid (HCl) and sulfuric acid (H2 SO4 ) using ammonium peroxydisulfate as an oxidizing agent. The absorption spectra of pure PANI salt and its doped state, in HCl and H2 SO4 media, have been studied in the wavelength range from 200 to 1100 nm using ultraviolet and visible near infrared spectrophotometer. Tauc’s formula, Lambert-Beer’s relation, and Fresnel’s formula were employed in the MATLAB program to calculate the optical energy gap, refractive index, and dielectric constant. Results showed that doping with HCl and H2 SO4 acidic mediums caused a reduction in the direct energy gap of the pure PANI from 2.69eV to 2.42 eV and 2.54 eV, respectively. The reduction in optical energy gap is associated with the increase in refractive index. The refractive index (2.92) has a higher value of PANI doped with HCl. Higher refractive index values are for better-structured films
The Economics of Using Solar Energy: School Buildings in Saudi Arabia as a Case Study
Get PDFAs a result of increasing population and building of new schools in Saudi Arabia, the demand for electricity is growing rapidly. In this context, the utilization of renewable energy resources such as solar energy appears to goal since it is abundant and holds huge ecological and economic promise. This study aims to provide a new entrance in school buildings’ design and construction by studying the current situation of energy consumption, the possibility of using solar cells, and the economics of its exploitation in school buildings. Interviews were conducted in school buildings at different levels in Arar city as a case study to collect data on energy consumption. Furthermore, a base case school building was selected for studying detailed energy consumption, and then, photovoltaic (PV) energy was proposed to use the on-grid system in accordance with governmental regulations. The study concluded that the use of PV energy in school buildings is economically feasible in addition to that more incentive from the government is needed for wide penetration use in Kingdom Saudi Arabia
Physicochemical Quality and Genotoxic Potential of Wastewater Generated by Canteen Complex
Get PDFCanteens generate high volumes of wastewater that should constantly be subjected to physicochemical and genotoxicity screening. In this study, the wastewater generated by a canteen complex was screened for physicochemical properties and genotoxic potential using standard procedures and Allium cepa chromosome assay. Results showed that the wastewater had total suspended solids, total dissolved solids, and total hardness concentrations of 120.70 mg/l, 554.50 mg/l, and 500.00 mg/l, respectively. The chloride concentration of the wastewater (7873.60 mg/l) was much higher than the recommended limit of 250 mg/l. The wastewater inhibited root growth in A. cepa at 0.1%, 1%, 10%, 25%, 50%, and 100% concentrations but promoted root growth at 2% and 5% concentrations. The wastewater was highly mitodepressive, with mitotic inhibition generally increasing with rising concentrations. The major chromosomal aberrations observed in A. cepa exposed to different concentrations of canteen wastewater were vagrant, sticky, and bridged chromosomes. No chromosomal aberration was observed in onion roots exposed to water (control). The differences in total chromosomal aberrations across wastewater concentrations were not statistically significant (P > 0.05). In view of these results, the practice of discharging untreated canteen wastewater into drainage canals may not be environmentally sustainable
Pollution Problems in Koya City due to Private Electrical Generators
Get PDFKoya city, like any other city in the world, faces a critical environmental problem which is global warming and the increase in the rate of production of gaseous pollutants. This research is involved with the negative effects of private Electrical Power Generators (EPGs) on the environment in Koya City. The environmental pollutants resulted from EPGs were investigated by performing an actual study on land for the number of (EPGs), types, and distribution. Koya city is divided into 18 quarters. The investigation covers a period from 2009 to 2017, included. The production of power was increased due to the increase in the number of generators and supplying hours. The power production in 2009 was 23,850 megawatt (MW) whereas it was 49,635 MW in 2017. The amount of fuel consumed in 2009–2017 was relatively increased from 30,000 to 62,500 barrel/year. The total amount of pollutants was increased by about 108% during the period 2009–2017. The results showed that the most significant increase in pollutants was carbon dioxide (CO2). The annual amount of (CO2) emitted in 2009 was 6588 tons whereas it has increased in 2017–13710 tons. The conclusion of this study was that the highest pollution occurred in the center of Koya City in Nabeel quarter, which represented 22% of the whole pollutants
L-Tryptophan as Fluorescent Probe for Determination of Folic Acid in Some Pharmaceutical Products
Get PDFA new fluorescent probe L-Tryptophan was reported for the determination of folic acid (FA), based on its quenching effect of the fluorescence intensity of L-Tryptophan. The concentration of folic acid was proportional to the quenched fluorescence intensity of L-Tryptophan at an emission wavelength of 365 nm in Britton– Robinson (BR) buffer solution of pH 7. Optimized conditions of pH, time, order of addition of the reagent, potential interferences, concentrations of L-Tryptophan and buffer were investigated. Folic acid was determined in a linear range of 2.0 to 16.0 μg ml-1 with a correlation coefficient R2 0.9974. The limits of detection LOD and quantification LOQ values were 0.09 μg ml-1 and 0.27 μg ml-1, respectively. The standard deviation (RSD) values for five replicated measurements of 2, 8, 16 μg ml-1 folic acid were between 0.23 % and 1.07%. This method is efficient for routine analysis and quality control assay as it is relatively interferences free
Skin Temperature Distribution over Human Head Due to Handheld Mobile Phone Call using Thermal Imaging Camera
Get PDFThe possible biological hazards due to the mobile phone electromagnetic (EM) field exposure are caused mainly by a temperature rise in tissue. Hence, the calculation of temperature in tissue may be more realistic than the calculation of specific absorption rate (SAR) due to the more direct relationship between temperature and safety. The heat transfer to human tissue due to a phone call is caused by a combined effect of conductive heat transfer caused by the basic non-microwave-related activity of the mobile phone and the absorption of the microwave. This paper investigates the role of heat transfer in living tissue due to thermal conduction. This is achieved using a thermal imaging camera to measure and map the skin temperature distribution over human head due to mobile phone EM emission. Two commercial mobile phone brands, that is, Apple iPhone 7 Plus and Huawei P20 Pro, are used at 1800 MHz cellular connection and approximate radiated power of 0.125 W to measure the skin temperature over human head at both, cheek and tilt position for 6 and 30 min calls. The results show that in spite of the direct proportion between the deposited SAR and temperature increase in human tissues, the heat transfer due to thermal conduction may not directly proportional to the SAR, where other factors may play important roles, for example, mobile phone chassis material, heated battery, antenna location inside the mobile phone, and mobile phone position in close proximity to head
Electrical and Structural properties of Copper Oxide (CuO) Thin Films on Plastic Substrate Deposited by Spray Pyrolysis Technique
No full text In this paper, copper oxide (CuO) thin films were deposited on polyimide plastic substrates by spray pyrolysis technique at different temperatures from 250 to 300°C. All the deposited films were characterized by X-ray diffraction (XRD) technique, ultraviolet (UV)-visible spectrophotometer, and hall effect measurements for the investigation of structural, optical, and electrical properties. The effects of substrate temperature on the structural, optical, and electrical properties of the films were studied. The XRD results revealed that all the CuO films have a facecentered cubic structure. The crystallite grain size was calculated using Scherrer formula and it was found that at the substrate temperature of 300°C, the CuO film presented maximum crystallite grain size of about 81.2 nm. The root mean square (RMS) roughness of the films was measured by scanning tunneling microscopy. RMS was increased with the rise of temperature. The optical transmission measurements by UV-visible spectrophotometer were used to determine the energy gap of the CuO films. Results showed that the optical energy gap has decreased with increasing the substrate temperature. Hall effect measurements showed that all the films are of p-type conductivity. Depending on the substrate temperature, hall measurement showed that the electrical resistivity and carrier concentration are varied from 77.4 Ω cm to 52.7 Ω cm and from 6.3 x1015 cm-3 to 10.1 x1015 cm-3., respectively
Docking Study to Predict the Efficacy of Phosphatidylinositol 3-Kinase α Inhibitors
Get PDFThe phosphatidylinositol 3-kinase (PI3K) family comprises lipid kinases that cross-link signals between living cells and their surroundings. PI3Ks are classified into several groups and isoforms with specific characteristics and functions. Genes encoding PI3Ks are mutated in several types of cancer, and their isoforms have varying capacity in promoting cell signaling and cancer progression. Many compounds have been introduced as PI3Kα inhibitors, but not all of them have the same inhibitory effects. For successful PI3K-related biomedical experiments, it is vital to select the most specific and potent compounds with the highest inhibitory effects for targeting this kinase. In this study, we investigate 28 well-recognized PI3Kα inhibitors through predicting their specificity and potency using the docking software AutoDock Vina. Our data showed that PF 05212384 had the highest docking score (−9.2 kcal/mol), and 3-methyladenine had the lowest docking score (−4.8 kcal/mol). Our data also showed different types of interactions and bonds formed between the inhibitors and protein residues. In conclusion, PF 05212384 and AZD 6482 compounds are the best candidates for targeting PI3Kα. In addition to hydrophobic interactions in the PI3Kα binding pocket, the formation of hydrogen bonds between these inhibitors and binding pocket residues was confirmed
Synthesis of New Series of Pyrazoline, and Study their Kinetics and Reaction Mechanism
Get PDFA new series of novel pyrazoline compounds were synthesized by addition of thiosemicarbazide to the 2,6-dibenzylidenecyclohexanone (Chalcone) and its para substituted derivatives. This study was conducted for four purposes. Firstly, a series of five membered ring pyrazoline compounds were synthesized and the structure of all new products obtained are supported by spectral data (1H-NMR, 13CNMR, IR and UV-Vis.), and the effect of substituents were studied. Secondly, the reaction kinetics of the new synthesized compounds were studied to investigate the reaction mechanism pathway and order of the reaction; it was found that, the reaction undergoes via Claisen route of mechanism with first-order reaction. Thirdly, the thermodynamics of the reaction were studied, the rate of the reaction, Arrhenius parameters (A), and thermodynamic parameters for activation includes (free energies (Ea), entropies (ΔS#), and Gibbs free energy (ΔG#) were estimated. Finally, the compensation effect was also studied, and found the same pathway for all of the synthesized pyrazoline compounds
Changes in the Levels of Some Biochemical Parameters in the Serum of Children in Response to the Giardiasis Infection
Get PDFGiardiasis is one of the most common intestinal protozoan infections worldwide. The study aimed to determine the levels of a number of biochemical parameters in the sera of children with giardiasis without receiving any medication for the treatment of giardiasis or intestinal helminthic infections in the previous 7 days. The study conducted 34 (19 females and 15 males) children and 34 (18 females and 16 males) healthy children as a control group. The mean ages of infected children and control groups were 8 ± 2 and 7 ± 2 years, respectively. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, urea, sodium, potassium, uric acid, and albumin were determined. AST level in males was significantly higher than healthy children control (14.20 ± 1.896 and 10.06 ± 0.699), respectively (P < 0.05), and no significant difference in females was noticed whereas the significant increases in ALT level were found when compared to control (12.43 ± 0.806 and 8.666 ± 0.449), for female, respectively, whereas no significant change in males was observed. Creatinine levels showed significant decrease in females when compared to control (57.72 ± 1.170 and 73.37 ± 1.635) (P ≤ 0.001), respectively