Materials Science Forum Vol. 1039

Abstract: Bulk Germanium monosulphide (GeS) alloy was synthesized using the usual melt-quenching technique. Its grains were used as the source material to deposit thin films by vacuum thermal evaporation. Thin-films samples were doped with 1, 2, and 3 at.% indium by thermal co-evaporation and annealed in a vacuum at temperatures 373, 473 and 550 K for an hour. Compositional, structural, and morphological properties of the bulk GeS alloy and its thin films were investigated by Energy Dispersive X-Ray Spectroscopy (EDS), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) techniques. The analyses verified the stoichiometry (GeS) of the starting material in the prepared thin films. They also revealed that the thin films under study are amorphous, homogeneous, without any cracks deposited uniformly on the glass substrate with thickness 650 to 700 nm.

Abstract: Thin films of CdO doped with AgNPs were deposited on ITO quartz substrates using DC sputtering protocol. The films were characterized using different techniques like XRD pattern for both undoped and doped one CdO NPs with silver nanoparticles, with various doping concentrations (0.4, 1.04, and 1.20) at%. It has been noticed from X-ray pattern that the nanostructured films possessed polycrystalline reflection patterns and the Prevailing orientation plane (111) on 2θ=33.35o in addition the reflection intensity increases with increasing of the doping concentration (1chip, 2chips and 3 chips) of Silver nanoparticles that chipped to the surface cadmium plate. Microstructures characterization of synthesized samples was studied using SEM. Images of SEM demonstrated that the particle size increases directly along with the number of implanting Silver NPs with three chips (1, 2 and 3) to the essential plate of Cd metal. EDXS spectroscopy counting the elemental composition using the atomic percentage, it has been demonstrated existence of silver in doped once. More, the percentage of silver content increase with increasing the number of Ag chips increases as follows The Ag content in the doped films of the cadmium metal plate with 1 attached is (1.39 wt. % for one Ag chip, 2.02 wt. % for two Ag chips while, the concentration has been increased further for three Ag chips to 3.24 at. %. Sensitivity of the manufactured device to Sevoflurane Anesthetic Gas Sensor indicates that the resistance decreases with the increase in the number of silver chips, and this is due to an increase of the pure charge carriers of the current. Keywords: Cadmium Oxide, Sliver, Structural Properties, DC reactive magnetron sputtering method, Sevoflurane Anesthetic Gas.

Abstract: In this research, SnO₂ nanostructure thin films were fabricated by spray pyrolysis method, using concentration of tin (Sn) salt solution deposited on a glass substrate at temperature of 450 °C. The tin solution was prepared by solves 2.2563gm of SnCl₂.2H₂O (molecular weight 219.4954 g/mole) in 100 ml of ethanol, then add 60 drops of pure hydrochloric acid ( HCl) using drop by drop technique. Different concentrations of antimony oxide (1%, 2%, 3%, 4%) hve been used to depose the thin films. The structure has been examined by X-ray diffraction technique, which shown that all films are polycrystalline with tetragonal rutile crystalline structure with preferential orientation in the (200) direction and, grain size decreases with increasing doping concentration. Optical measurements shown that the films are transparently in the visible region, with an average transmittance more then 80% and, sharp absorption edge nearly at 350 nm, the nature of the optical transition were direct allowed with band gap varies between (2.97 - 3.75 eV) which is directly proportional to doping concentration. The results also show that the doping has led to improved the response time of the sensing. Two kinds of gases NO₂ and NH₃ have been used to test the sensing performance, at different operating temperatures (R.T, 100, 200, 250, 300 and 350) oC , and bias voltage (3 Volt). For NO₂ gas the highest sensitivity was 77%, the shortest response time 2.9 s and the recovery time 19 s, while for NH₃ gas sensitivity was 11.5%, the response time 4.1 s and the shortest recovery time 20s,

Abstract: In this paper, the absorption and fluorescence spectra of Erythrosine dye laser liquid solution dissolved with acetone and ethanol solution were studied in different concentrations (10^-3, 10^-4, 10^-4 M). The results showed an increase in absorption and fluorescence intensity by increasing polarity of the solvent. Some of the linear optical properties of the prepared models were also studied. The results showed an increase in the absorbance, linear refractive index, and linear absorption coefficient with an increase in solvent polarity and the molar concentration against a decrease in the permeability value, as well as the quantitative production efficiency was calculated based on the results of the absorption spectra and fluoridation. The Purpose of the search Study the effect of solvent polarity on both absorption and fluorescence spectra, and on linear and electrical optical properties. Keywords: Erythrosine Laser dye, absorption, fluorescence spectra and Polar solvents (acetone and ethanol).

Abstract: In this study, Cu₂FeSnS₄ (CFTS) thin films were deposited on glass substrates at different temperatures of 250, 300, 350, 400, and 450 °C using the chemical pyrolysis technique. This work aimed to study the effect of substrate temperature on film properties. The film's structural properties were obtained via X-ray diffraction, Raman spectroscopy, and Field Emission Scanning Electron Microscopy (FESEM). The UV-Vis spectrum determined the optical properties; and the electrical properties were obtained through observation of the Hall effect. Analysis of XRD pattern showed that the CFTS thin films have a tetragonal structure with a main peak corresponding to the direction (112). Results of Raman spectroscopy displayed a unique peak at 318 cm^-1, suggesting a quaternary compound of CFTS. The FESEM tests confirmed the presence of nanoparticles of various shapes and sizes. The CFTS films have a band gap of 1.77-1.92 eV and an absorption coefficient in the visible spectrum region higher than 10⁴ cm^-1, which confirms their use as an active layer in solar cells. The mea measurements of the Hall effect of the CFTS thin films showed a p-type conductivity for all films, with the maximum charge carrier density and mobility occurring at 400 °C, making them suitable for photovoltaic applications.

Abstract: The production of a high-sensitivity surface Plasmon resonance (SPR) sensor depends on a few main factors, such as metal thin film types and thicknesses, light coupling techniques and acceptable EM wave polarization modes. This work is carried out to investigate the impact on the SPR characteristics of noble metal thicknesses, namely gold and silver, for optical sensor applications. To excite surface Plasmon polaritons (SPP), a Kretschmann prism coupling was used. The thicknesses of noble metal thin films were varied between t=30nm and 60nm. The characteristics of SPR peaks such as Q-factor and FWHM were studied in SPR signal analyses. In comparison with silver, Q-factor results showed an outstanding optical property of gold at t= 40 nm due to its high Q-factor values, which confirms its ability to produce excellent SPP quantities. In conclusion, gold noble metal at t= 40nm is capable of producing optimum SPR. In the development of the highly sensitive SPR sensor, this excellent criterion put gold as a spectacular candidate for optical sensor applications.

Abstract: In this work, theoretical investigation in coherent manipulation throughout local density of states calculation for serially coupled double quantum dots embedded between ferromagnetic leads (FM-QD1-QD2-FM) by using the non-equilibrium Green's function approach. Since the local density of states are formulated incorporating the spin polarization and the type of spin configuration on the leads. Our model incorporates the inter-dot hopping, the intra-dot Coulomb correlation, the spin exchange energy and the coupling interactions between the quantum dots and leads. The results concerned to the parallel configuration at strong inter-dot coupling regime shows that the spin down electrons in the quantum dots may be more coupled coherently if the regime is tuned. The local density of states of the two dots for spin up electrons shows a broad hump with small splitting i.e. the case is decoherent for spin up electrons. In the case of weak interdot coupling it is obvious that the spin dependent density of states on the quantum dots show that the resonances are not well splitted. For the antiparallel configuration in the strong coupling regime, the spin dependent density of states of the double quantum dots show four peaks but with broaden and overlapping. In the case of weak coupling regime, the total spin dependent density of states, which have two peaks with certain board, one can conclude that the states are not coupled coherently. The case of the antiferromagnetic nature of the spin exchange interaction, our calculations for the parallel and antiparallel configurations (in strong and weak regimes) show a decoherence state.

Abstract: In general, the lower prosthesis consists of socket, leg, ankle, and foot. The socket is the crucial part for connecting the remaining part of the limb and the prosthesis, as it is essential to distribute the load to the amputation patient to provide comfort and add to the proper appearance of the amputation patient. A research that was included methods of manufacturing it, choosing the composite materials necessary for the design, higher durability, lighter weight, and less cost. Previous research used polymer composites reinforced with fibers as glass fibers, carbon fiber, and Kevlar. Other researchers have studied natural fibers' use as reinforcement fiber by mixing resin materials or adding nanomaterials to modify the mechanical properties and reduce costs. After calculating performing the required mechanical tests such as tensile, fatigue, and impact testing, the required properties of the composite material are found, where the prosthesis socket is manufactured below the knee with the application of different loads of the socket. A review of socket models used in developing countries was performed with regard to design, modeling, and finite element analysis (FEA). This review aims to study the material's behavior and mechanical properties by using natural fibers for manufacturing prosthetic sockets. The review discusses the socket manufacture methods proposed to develop the socket industry based on natural fibers to reduce the hot and humid environment using Kenaf and other natural fibers.

Abstract: Most artificial socket prostheses are applied to fatigue load; therefore, more failure of socket prostheses occur due to fatigue loading. Then, it was necessary to improve the fatigue characterizations of composite materials used to manufacture the artificial socket prostheses by using hybrid nanomaterials, with different types and amounts. So, this work suggested mixing two nanomaterials types to improve the mechanical and fatigue properties of composite materials. Therefore, the experimental work used to manufacture tensile and fatigue samples of composite with different nanoweight fraction effects, in addition to calculating the mechanical properties and fatigue behavior for its composite. There, strength and modulus of elasticity, in addition to, fatigue strength and life evaluating of composite with different nanomaterials mixing. Also, the numerical technique by using the finite element method is used to calculate fatigue life and strength of composite materials. Also, comparison fatigue results were calculated by experimental work with fatigue results evaluated by numerical technique to give the discrepancy for results evaluation. Hence, the comparison of results showed good agreement for the technique used to evaluate the fatigue behavior of composite materials with the nanoeffect, where, the maximum error did not exceed (11.86%). Finally, the results have shown that the reinforcement by mixing two Nanomaterial types lead to improvement in the mechanical properties and fatigue behavior to more than (35%) and increasing the mechanical properties and fatigue behavior to (10%) more than the increase of properties and fatigue characterizations reinforcement by one Nanomaterial type.

Abstract: Using the sol-gel process, glass powder was made. After the preparation method of the glass powder, x-ray analytical (XRD), particle size analysis and Fourier Transform Infrared (FTIR) were performed. The particle size analysis of manufactured glass (13-93) is found to be about 2.978 μm. (XRD) mode analysis suggested that the resulting porous scaffolds were amorphous. Using the process of salt leaching to create bioactive glass scaffolds (13-93) with structural and physical properties suitable for the human trabecular bone. XRD spectroscopy, scanning electron microscopy (SEM) and FTIR after sintering at temperature 750 °C were used to investigate the microstructure and chemical bonding of the porous scaffolds. The synthesized scaffold was soaked in medium of the simulated body fluid (SBF) and examined by SEM and XRD analysis in order to evaluate bioactivity. From the SEM morphology analysis results, it was noticed that the scaffolds comprised open and interconnected pores with a porosity range of 75-78%. High bioactivity of pours scaffolds was reported to have been observed after soaking 7days in SBF media because of the formation of apatite layer on its surfaces. Keywords: bioactive glass (13-93), scaffold, salt leaching method, SBF, sol-gel.