The goal of this study was to investigate the optical properties of the prepared polyvinyl chloride (PVC)/zinc oxide (ZnO) nanocomposite films. The PVC/ZnO nanocomposite films consist of the addition of different concentrations with both non-annealed ZnO nanoparticles and ZnO nanoparticles annealed at temperature of 700°C. The PVC/ZnO nanocomposite films by weight concentrations of (0 wt.%, 2.5 wt.%, 5 wt.% and 10 wt.%) have been prepared by the casting method. The optical absorbance and transmittance values of the composites films were measured in the wavelength range between (250 to 1100 nm) at room temperature by using the UV-1800 Shimadzu spectrophotometer. The optical properties (absorption coefficient, dielectric constant, refractive index, and optical conductivity) have been investigated by the ultraviolet (UV) spectrophotometer. The optical parameters (direct optical energy gap, excitation energy for electronic transitions, the dispersion energy, static refractive index, static dielectric constant, optical oscillator strengths, the moments of optical spectrum, linear optical susceptibility, third-order nonlinear optical susceptibility, nonlinear refractive index, high-frequency dielectric constant, the carrier concentration to the effective mass ratio, the long wavelength refractive index and the plasma frequency) were calculated. The results showed that the optical properties behavior of the PVC/ZnO nanocomposite films was found to be dependent on the ZnO concentration, and photon wavelength. In addition, the results of the study show that the optical parameters can be influenced by alter the concentration of the nonannealed and annealed a ZnO nanoparticle in the PVC polymer matrix.
Hot and arid areas are considered a harsh environment when it comes to cleaning photovoltaic (PV) modules. Minimizing the panel tilt angle makes it evident that dust and other substances such as airborne dirt (both organic and inorganic) and bird droppings can build up over time and impact the amount of electricity generated by a module. The current study aims to find the most effective and optimum cleaning technique/material based on cleaning performance of the PV panel. The effects of different easy-to-clean materials on the performance of poly crystalline silicon type PV modules were experimentally investigated. As there is no specific recommended material to clean solar panels, the cell surface was coated with different types of easy-to-clean materials available in the Jordanian local market. The cleaning materials utilized were: Crystal glass coating type AJJL-CSS, jiajialy nano energy saving & anti UV solution, GIE (Galsilk 7, isopropanol, ethanol, water), TGIE (TiO2, Galsilk 7, isopropanol, ethanol, water), sodium hexa meta phosphate, and NanoUltra. Results from temperature measurements and output voltage of coated cells showed that all coating materials were able to reduce the cell temperature in different scales. The jiajialy nano energy saving & anti UV solution provided the best cooling effect, while the GIE and TGIE showed good results, too. Output voltage of cells coated with GIE and TGIE materials was the highest.
In the present study different copper-lead-tin alloys were prepared by casting. A wear test device was designed and manufactured to study the wear resistance of these alloys under different values of contact forces and sliding velocities. The data obtained from the wear test is modeled by the Adaptive Nearo Fuzzy Inference System (ANFIS) to predict an alloy of the highest wear resistance. Comparison between predicted an experimental wear results show good agreement. There are more than one combination of the considered copper alloy that show optimum resistance to wear, namely an alloy composed of (Cu = 75 %, Pb = 5 %, Sn = 20 %), and that composed of (Cu = 85 %, Pb = 5 %, Sn = 10 %).It was also found that the increase of lead decreases the wear resistance, while percentage of tin above 7 % increases the wear resistance of these copper base alloys. This is attributed to the change in the micro-structure of the tested alloys.
Generally, sheet thickness plays a significant role in the selection of appropriate process parameters in order to produce high quality weld joint in the laser welding process. The heat sink capacity and weld penetration are known as two criteria that are mainly influenced by sheet thickness. In this study, the effect of sheet thickness, welding speed, nozzle distance, and laser power were investigated in order to determine the temperature distribution near the melt pool, dimensions of molten pool through experimental and numerical analysis. The weld joint mechanical characterization was determined via elongation rate and tensile strength. The highest value of tensile strength is about 80% of the typical base metal and the elongation of the welded samples achieved about 40% of the base metal. The thinner sheets showed more sensitivity related to the elongation of the joint by increasing the welding speed. Also, the temperature rise with increasing laser power near the melt pool for the thinner sheet was about 200 °C in comparison to the 3 mm sheet, which is about 90 °C. The obtained simulation results for the maximum temperature discrepancy at near the melt pool was 12 °C and 4 °C for 1 and 3 mm thickness orderly, which depicts good agreement with the temperature experimental results.
Si nanowires are of interest for photovoltaics and sensors. We report about the growth of Si nanowires from SiH4 using a Au catalyzed vapor‐liquid‐solid (VLS) growth process in a tube furnace at atmospheric pressure. At elevated growth temperatures, single crystalline wires with clear facets are obtained. The influence of the furnace temperature and the Au layer thickness on the nanowire growth is investigated in detail. The orientation of the wires has been studied by EBSD. For electrical characterization, Pt metal contacts have been applied to individual wires using Pt deposition in a FIB microscope. The high values found for the conductivity indicate that Ga implantation occurs during the FIB process. Electrical characterization under illumination shows the presence of a significant photoconductivity. Further functionalization of the Si nanowires will be done by combining them with luminescent nanoparticles (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.