Study of the Dielectric Behaviour of Pure Polypropylene (PP) and Polypropylene Banana Fiber (PP-B) Composites
Md. Nazrul Islam,
M. A. Gafur,
Amir Hossain Khan
Issue:
Volume 4, Issue 1, June 2020
Pages:
1-6
Received:
21 February 2020
Accepted:
6 March 2020
Published:
28 May 2020
Abstract: This paper reports the dielectric properties of banana fiber reinforced thermoplastic composites. In this research synthetic polymer, polypropylene was used matrix and natural fiber, banana fiber was used as the reinforcing material. Polypropylene [-CH2-CH2-CH2-]n and different fiber content (wt.%) of polypropylene-banana fibers (natural fiber) composites were fabricated using a hot-press moulding system. The short fiber percentages was varied as 0%, 10%, 20%, and 25% with the matrix materials. The optimum fabrication parameters were established (initial pressure, temperature, etc.), and also optimum short fiber percentage was selected. These composite test samples were fabricated so the short fibers were randomly oriented in the matrix. The electrical properties like dielectric constant and dielectric loss tanjent were measured by a dielectric measurement set up. The measurement was performed over a wide range of frequency of 60 Hz to 3 MHz and temperature range from 303K to 383K. The results obtained for the composite varied with the variation of fiber percentage. Experimental results of the dielectic properties of pure polypropylene and polypropylene-natural fiber composites were compared. It has been established that the fabricated composition changes its insulating property after adding the natural fibers. The certain percentage of natural fiber addition gives the better dielectric properties and dialectic tanjent.
Abstract: This paper reports the dielectric properties of banana fiber reinforced thermoplastic composites. In this research synthetic polymer, polypropylene was used matrix and natural fiber, banana fiber was used as the reinforcing material. Polypropylene [-CH2-CH2-CH2-]n and different fiber content (wt.%) of polypropylene-banana fibers (natural fiber) com...
Show More
Structural, Optical and Electrical Properties of Eu-doped CuS Nanoparticles Synthesized Through the Aqueous Route
Nouha Loudhaief,
Mohamed Ben Salem,
Mouldi Zouaoui
Issue:
Volume 4, Issue 1, June 2020
Pages:
7-14
Received:
18 November 2019
Accepted:
29 November 2019
Published:
28 May 2020
Abstract: Eu-doped CuS nanoparticles stabilized by L-cysteine were synthesized by a low-temperature soft aqueous route. X-Ray Diffraction (XRD) patterns of the synthesized products reveal the formation of the hexagonal structure of covellite CuS. Scanning Electron Microscopy (SEM) images depict that the as-prepared nanoparticles exhibit relatively sphere like shaped morphology. Transmission Electron Microscopy (TEM) analyses show that the average size of the nanoparticles was found to be reduced with increasing the Eu concentration. UV-Visible optical absorption measurements reveal that the optical band gap is increased with increasing the Eu concentration, showing the presence of a blue shift due to quantum size effects. Impedance spectra were well modelled by introducing an electrical equivalent circuit. The electrical conductivity was found to be increased with increasing the Eu concentration. The temperature dependence of the DC conductivity confirmed the semiconducting nature of the as-prepared nanoparticles and was found to obey the Arrhenius law with two activation energies. The frequency dependence of the AC conductivity has been analyzed by Jonscher’s power law suggesting the non-overlapping small polaron tunneling (NSPT) type of conduction. The polaron hopping energy was found to be increased with increasing the Eu concentration. The dielectric constant of the as-synthesized nanoparticles was found to be decreased with the increase in Eu concentration. The dielectric loss tangent was found to be decreased and then increased at higher frequencies with increasing the Eu concentration.
Abstract: Eu-doped CuS nanoparticles stabilized by L-cysteine were synthesized by a low-temperature soft aqueous route. X-Ray Diffraction (XRD) patterns of the synthesized products reveal the formation of the hexagonal structure of covellite CuS. Scanning Electron Microscopy (SEM) images depict that the as-prepared nanoparticles exhibit relatively sphere lik...
Show More
Fabrication of Alternative Bolus for Cobalt-60 Teletherapy Using Two Locally Available Materials
Abayomi Moses Olaosun,
Caleb Ayoade Aborisade,
Iyobosa Blessing Uwadiae,
Denen Eric Shian,
Fatai Akintunde Balogun
Issue:
Volume 4, Issue 1, June 2020
Pages:
15-18
Received:
9 April 2020
Accepted:
8 June 2020
Published:
4 August 2020
Abstract: Bolus is a tissue equivalent material which is use in radiation therapy in order to eliminate skin sparing effect of higher energy photon beams that always reduce the surface dose. There are several commercially bolus material such as Superflab, Aquaplast and gels for use but literature have shown that they are expensive and are not readily available in developing countries. This work presents the fabrication of an alternative bolus for Cobalt-60 Teletherapy using two locally available materials (Beeswax and Petroleum jelly). Beeswax was liquefied at a temperature of 60°C followed by the addition of Petroleum jelly at ratio 3:1 by weight for proper molding and flexibility. In order to determine the depth of maximum dose, Thermoluminescent Dosimeter (TLD) chips were inserted in between ten bolus materials of thickness 0.5 cm that were arranged in layers and placed on a solid water phantom. This was then irradiated with Cobalt-60 radiation source using field size ranging from 5 cm x 5 cm to 10 cm x 10 cm field size. For all the field size, maximum absorbed dose was found to be at 0.5 cm depth. This depth of maximum dose was compared to two tissue equivalent materials in use in radiation therapy: water and Superflab for Cobalt-60 Teletherapy and found to be in agreement. The percentage dose deviation when compared with water for 1 cm, 2 cm, 3 cm, 4 cm and 5 cm were less than 2%. The flexibility of the bolus material and the analysis of the absorbed dose measured have shown that the fabricated bolus material of thickness 0.5 cm can be used as an alternative bolus material for Cobalt-60 Teletherapy.
Abstract: Bolus is a tissue equivalent material which is use in radiation therapy in order to eliminate skin sparing effect of higher energy photon beams that always reduce the surface dose. There are several commercially bolus material such as Superflab, Aquaplast and gels for use but literature have shown that they are expensive and are not readily availab...
Show More
