In the last few decades, growing interest has been shown in the development of new solar selective coatings based on transition metal nitride and/or oxinitride for solar absorbing applications. Solar thermal collectors are well thought out to be the most effective process of converting and harvesting solar radiation. In this investigation, Cu/TiON/CrO2 multilayered solar selective absorber coatings have been coated onto Al substrates using the dip-coating process followed by an annealing process at (400, 450, 500, 550, and 600 °C. The XRD analysis showed excellent crystalline quality for the prepared thin films along with enhanced surface features as proved by FESEM images, and the grains are in the range of (27–81) nm. The optical investigations revealed that the film annealed at 600 °C exhibits improved solar absorptance, thermal emittance, and solar selectivity of ~ (90.7 %), (5.8 %) and 15.6, respectively. Also, the highest values of hardness ~ (26.8 GPa) and Young’s modulus ~ (250 GPa) were assigned for the film annealed at the highest temperature. Calculated optical band gaps of fabricated thin multilayered Cu/TiON/CrO2 films were found to be in the range of (1.8 – 2.10) eV.
An accurate and sensitive spectrophotometric method has been developed for the determination of cefotaxime (CEF) in pure and pharmaceutical samples. The suggested method depended on the coupling reaction between diazotized cefotaxime and 3,5-dimethyl phenol (3,5-DMPH) in basic medium to form light orange, water soluble dye, that is stable and has a maximum absorbance at 497nm. The calibration graph was liner over the concentration range (1-70) µg.mL-1 with LOD of 0.750 µg.mL-1 and LOQ of. 2.740 µg. mL-1, sandal sensitivity of 0.0526 µg. cm-2 . molar absorptivity 11328 Lmol-1 cm-1 . The stoichiometry composition was found by Jobs a
... Show MoreThree phenol-formaldehyde resins having pendant maleimides were prepared by poly condensation of N-(hydroxyphenyl) maleimides with formaldehyde under conditions similar to those in Novolac preparation. The prepared resins were modified by two methods, the first one includes esterification of phenolic hydroxyl groups in the prepared resins via their treatment with benzoyl, acryloyl, methacryloyl and cinnamoyl chlorides respectively in the presence of triethylamine, while the second modification includes free radical polymerization of vinylic bonds in the prepared resins to produce cross-linked thermally stable polymers.
CuO nanoparticles were synthesized in two different ways, firstly by precipitation method using copper acetate monohydrate Cu(CO2CH13)2·H2O, glacial acetic acid (CH3COOH) and sodium hydroxide(NaOH), and secondly by sol-gel method using copper chloride(CuCl2), sodium hydroxide (NaOH) and ethanol (C2H6O). Results of scanning electron microscopy (SEM) showed that different CuO nanostructures (spherical and Reef) can be formed using precipitation and sol- gel process, respectively, at which the particle size was found to be less than 2 µm. X-ray diffraction (XRD)manifested that the pure synthesized powder has no inclusions that may exist during preparations. XRD result
... Show MoreDetection of early clinical keratoconus (KCN) is a challenging task, even for expert clinicians. In this study, we propose a deep learning (DL) model to address this challenge. We first used Xception and InceptionResNetV2 DL architectures to extract features from three different corneal maps collected from 1371 eyes examined in an eye clinic in Egypt. We then fused features using Xception and InceptionResNetV2 to detect subclinical forms of KCN more accurately and robustly. We obtained an area under the receiver operating characteristic curves (AUC) of 0.99 and an accuracy range of 97–100% to distinguish normal eyes from eyes with subclinical and established KCN. We further validated the model based on an independent dataset with
... Show MoreImage is an important digital information that used in many internet of things (IoT) applications such as transport, healthcare, agriculture, military, vehicles and wildlife. etc. Also, any image has very important characteristic such as large size, strong correlation and huge redundancy, therefore, encrypting it by using single key Advanced Encryption Standard (AES) through IoT communication technologies makes it vulnerable to many threats, thus, the pixels that have the same values will be encrypted to another pixels that have same values when they use the same key. The contribution of this work is to increase the security of transferred image. This paper proposed multiple key AES algorithm (MECCAES) to improve the security of the tran
... Show MoreSeepage through earth dams is one of the most popular causes for earth dam collapse due to internal granule movement and seepage transfer. In earthen dams, the core plays a vital function in decreasing seepage through the dam body and lowering the phreatic line. In this research, an alternative soil to the clay soil used in the dam core has been proposed by conducting multiple experiments to test the permeability of silty and sandy soil with different additives materials. Then the selected sandy soil model was used to represent the dam experimentally, employing a permeability device to measure the amount of water that seeps through the dam's body and to represent the seepage line. A numerical model was adopted using Geo-Studio software i
... Show MoreIn this work, CdO:In/Si heterojunction solar cell has been made by vacuum evaporation of cadmium oxide doped with 1% of indium thin film onto glass and silicon substrates with rate deposition (3.9A/sec) and thickness(≈250nm). XRD was investigated, the transmission was determined in range (300-1100)nm and the direct band gap energy is 2.43 eV, I-V characterization of the cell under illumination was investigated , the cell shows an open circuit voltage (Voc) of 0.6 Volt, a short circuit current density (Jsc) of 12.8 mA/cm2, a fill factor (F.F) of 0.66, and a conversion efficiency (η) of 5.2%.
Media and communication's research are varied in accordance to research approaches' variety which seeks to reach convergent social, psychological, political, economic, and technical point of views. Its main aim is to assimilate all the new variables in the communicative method, especially, social media sites research; concerning their methodology, tools and theories. It is due to their diverse - developed applications and their increased rates of public use becoming irreplaceable in our daily life. It is well reflected by their consequent impact on the the public beside their role in changing its views.
This clarifies the notable increase of scientific research that concern them manifesting the dialectica
... Show MoreIf the Industrial Revolution has enabled the replacement of humans with machines, the digital revolution is moving towards replacing our brains with artificial intelligence, so it is necessary to consider how this radical transformation affects the graphic design ecosystem. Hence, the research problem emerged (what are the effects of artificial intelligence on graphic design) and the research aimed to know the capabilities and effects of artificial intelligence applications in graphic design, and the study dealt in its theoretical framework with two main axes, the first is the concept of artificial intelligence, and the second is artificial intelligence applications in graphic design. The descriptive approach adopted a method of content
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