Compressive Behaviour Of Syntactic Foam Filled With Epoxy Hollow Spheres Having Different Wall Thickness.

An innovative approach of producing epoxy syntactic foams was developed by incorporating single-coated and double-coated of epoxy hollow spheres within epoxy resin matrix

Transformation of Generalized Chebyshev Lowpass Filter Prototype to Suspended Stripline Structure Highpass Filter for Wideband Communication Systems

This paper presents the transformation of generalized Chebyshev lowpass filter prototype to highpass filter using Suspended Stripline Structure (SSS) technology. The study involves circuit analysis to determine generalized Chebyshev responses with a transmission zero at finite frequency. The transformation of the highpass filter from the lowpass filter prototype provides a cutoff frequency of 3.1 GHz with a return loss better than -20 dB. The design is simulated on a Roger Duroid RO4350 with a dielectric constant, εr of 3.48 and a thickness of 0.168 mm. The simulation performance results show promising results that could be further examined during the experimental works. This class of generalized Chebyshev highpass filter with finite transmission zero would be useful in any RF/ microwave communication systems particularly in wideband applications where the reduction of overall physical volume and weight as well as cost very important, while maintaining its excellent performance

A Parametric Study on Dual-Band Meander Line Monopole Antenna For RF Energy Harvesting

This paper studies the dual-band monopole antenna based on meander line structure for Global System for Mobile Communications (GSM) band applications, which is also has the potential to be used for RF energy harvesting. A meander line antenna with a conductor line is investigated during the design using the Computer Simulation Tool (CST) software. The antenna is fabricated on a double-sided FR-4 printed circuit board using an etching technique. The comparison between simulation and measurement results for the return loss and radiation patterns are observed and are in good agreement. A bandwidth of 97 MHz and return loss of -19.29 dB is obtained at the first frequency band, i,e. 915 MHz, while a bandwidth of 46.2 MHz with a return loss of -16.27 dB are obtained at the second frequency band, i.e. 1800 MHz. This study is an early investigation in designing the RF energy harvesting to support green technology and sustainable development particularly for Wireless Sensor Network (WSN) as well as Radio Frequency Identification (RFID) applications

Characterization of Diesel-Hydrogen Peroxide Fuel Blend

In the present work, the outcome of Hydrogen peroxide–diesel fuel blends on the physicochemical properties and kinetic study has been studied. A various blends of diesel-hydrogen peroxide ranging from 5% hydrogen peroxide (H2O2), up to 15% by volume in several fuel blends were experimentally investigated and compared with standard diesel fuel. A new emulsifier has been developed for obtaining better emulsion between diesel and hydrogen peroxide. According to ASTM Standard for fuel tests, the results showed that hydrogen peroxide is capable of enhancing the diesel fuel properties. This is due to the presence of additional oxygen atom within the H2O2 molecule which can enhance the combustion process and ultimately affecting the exhaust emission. Keywords:ASTM test, diesel, hydrogen peroxide, physicochemical properties

Dual-Band monopole Antenna For Energy Harvesting System

A planar dual-band monopole antenna is presented for Global System for Mobile Communications (GSM) band applications, which also have the potential to be used for energy harvesting system. The proposed antenna comprises of a ground plane at the back of the FR4 substrate and three microstrip lines which are physically connected with each other at the top surface of the substrate. The monopole antenna achieves good return loss at resonance frequencies of 915 MHz and 1800 MHz with a bandwidth value of 124.2 MHz and 196.9 MHz respectively. The antenna gains of 1.97 dB and 3.05 dB are achieved at resonance frequencies of 900 MHz and 1800 MHz. Experimental results show good agreement with simulated performance. The output from the receiving antenna is also observed in order to analyze the relationship of the power level and the distance between transmitting and receiving antenna. This study is an early investigation in designing the RF energy harvesting system to support green technology and sustainable development particularly for Wireless Sensor Network (WSN) applications

Development of 99Mo/99mTc Generator System for Production of Medical Radionuclide 99mTc using a Neutron-activated 99Mo and Zirconium Based Material (ZBM) as its Adsorbent

Molybdenum produced from fission of U-235 is the most desirable precursor for 99Mo/99mTc generator system as it is non-carrier added and has high specific activity. However, in the last decade there has been short supply of 99Mo due to several constrains. Therefore, there have been many works performed for development of 99Mo/99mTc generator system using 99Mo which is not produced from either LEU or HEU. This report deals with development of 99Mo/99mTc generator system where zirconium-based material (ZBM) is used as adsorbent of neutron-activated 99Mo. The system was prepared by firstly irradiating natural Mo in the G. A. Siwabessy reactor to produce neutron-activated 99Mo. The target was dissolved in NaOH 4N and then neutralized with 12 M HCl. The 99Mo solution was then mixed with a certain amount of ZBM followed by heating at 90°C for three hours to allow the 99Mo adsorbed on ZBM. The 99Mo-ZBM (9.36 GBq of 99Mo was Mo/ 4.2 g ZBM) was packed on a fritz-glass column. This column was then fitted serially with an alumina column for trapping 99Mo breakthrough. The columns were then eluted daily with saline solution for up to one week. The yield of 99mTc was found to be between 53.7 – 74% (n= 5). All 99mTc eluates were clear solutions with pH of 5. Breakthrough of 99Mo in 99mTc eluates was found to be 0.031 ± 0.019 μCi 99Mo/ mCi 99mTc (n= 5) which was less than the maximum activity of 99Mo allowed in 99mTc solution (< 1 µCi 99Mo/mCi 99mTc). Aluminum breakthrough in 99mTc eluates was found to be less than 10 ppm. The radiochemical purity of 99mTc in form of Na99mTcO4 was > 99%. Radiolabeling of this 99mTc towards methylene diphosphonate (MDP) kit gave a radiolabelling efficiency of 99%. In summary, a new 99Mo/99mTc generator system that used neutron-activated 99Mo and ZBM as its adsorbent has been successfully prepared. The 99mTc produced from this new 99Mo/99mTc generator system attained the quality of 99mTc required for medical purposes.Received: 23 Februari 2016; Revised: 13 July 2016; Accepted: 17 July 201

A New Class of Dual-mode Substrate Integrated Waveguide (SIW) Filter with Two Metalized Posts

This paper presents the investigation and characterization of dual-mode Substrate Integrated Waveguide (SIW) filter with two metalized posts on the cavity to reduce the overall volume of RF front-end subsystems. By introducing two vertical metalized posts and two diagonal metalized posts in dual-mode SIW filter, both SIW filters show different flow of Electromagnetics (EM) can be identify from the E-fields. In order to compare which dual-mode SIW filter gives the better performance, the designs are simulated at centre frequency 2 GHz using CST Studio Suite software and the results are validate through measurement. The measurement shows a good agreement with the simulated results. This design is suitable for any integration microwave system where the reduced complexity of the design and cost as well as weight is very important for the wireless communication systems