Preparation and Study Optical Limiting of Gold Nps by Pulsed Laser Ablation in Distilled Water (DDDW)

Abstrac. In the present work, gold nanoparticle (Au NPs) was synthesis by pulsed laser ablation (PLA) by using Q-switched, (Nd: YAG) (E=80mJ) (λ=532,1064nm) and Number of pulses (500)pulse of the gold metal target in deionized water. The optical properties were studied with a UV-vis spectrophotometer which tests the absorbance spectra and comparison of the generated nanoparticles solution. atomic force microscope (AFM) results show that the grain size increase by decreasing wavelength. The optical limiter of the resulting colloidal solution was studied.

Design and fabrication of 2.4GHz rectangular patch antenna for Wi-fi application

In the last few decades, the development of wireless and mobile communication has influenced social and economic development. Billions of devices demand wireless connection which runs on data, voice and other applications. The antenna is an integral part of any wireless communication system. From the design perspective, the antenna must be compact, easy to manufacture, and cost-effective. This paper presents a design of a rectangular patch antenna, operating at 2.4GHz. The antenna is initially simulated on CST, required parametric sweep is carried out in terms of length and width of the patch, to resonate at 2.4GHz. The simulated antenna is then printed using a PCB printing machine, PCB Prototyping System, Eleven Lab. The printed antenna was tested using Keysight’s PNA-LN-5232A (Vector Network Analyzer). The measurements/ variation in the reflection coefficient were observed /noted within the vicinity of the human body and gold metal plus the human body, at different positions. Near the ear. The simulation results and measured results are in a good match. The designed antenna is suitable for the Wi-fi, WLAN, communication application.