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All Journal POSITRON Jurnal Ilmu Fisika Specta Journal of Technology
Rahastama, Swastya
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Astronomy Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Earth & Planetary Sciences Electrical & Electronics Engineering Energy Environmental Science Materials Science & Nanotechnology Physics

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Journal : POSITRON

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The Self-Absorption Effect of Ni-63 Beta Source to the Silicon Carbide based Betavoltaic Battery Rahastama, Swastya; Saputra, Yohannes Dwi; Waris, Abdul
POSITRON Vol 10, No 2 (2020): Vol. 10 No. 2 Edition
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam, Univetsitas Tanjungpura

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (741.177 KB) | DOI: 10.26418/positron.v10i2.42006

Abstract

A typical planar structure is the most feasible conceptual design of betavoltaic battery due to its simplicity. The self-absorption of beta source, however, causes a limitation to the geometrical efficiency.  Herein, we tried to investigate the self-absorption event in Ni-63 beta source by changing the geometrical aspects and evaluated its effect on each layer of a 4H-SiC semiconductor as the radiation-electricity converter. The design configuration from previous literature was adopted and the model was developed using Monte Carlo N-Particle X (MCNPX) consists of radioisotope source, semiconductor, and also ohmic contacts. The energy of beta emission was adjusted to the actual Ni-63 beta spectra with an isotropic distribution of ejected particles. The average beta energy deposition degrades along with the addition of source mass thickness, but the n+ substrate has a unique result where a peak is observed at 0.1246 mg/cm2 due to the self-absorption effect. Furthermore, the rectangular surface area magnification gives a positive impact on the beta energy deposition up to 2.48% and the photon average energy deposition up to 137.21%.  The results of average electron absorbed dose are consistent with Oldano-Pasquarelli semi-empirical theory of self-absorption in the beta source, where the upper layer receives a wider angular distribution of particles compared to the lower one, which corresponds to the counting geometrical coefficients.
Effect of Heat Leakage on Relativistic Quantum Lenoir Engine Performance with a Massless Boson as Working Substance in the Infinite Potential Box Saputra, Yohanes Dwi; Rahastama, Swastya; Firdaus, Rohim Aminullah
POSITRON Vol 14, No 1 (2024): Vol. 14 No. 1 Edition
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam, Univetsitas Tanjungpura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26418/positron.v14i1.64658

Abstract

A study on the effect of heat leakage on power output, thermal efficiency, and reversibility rate in a relativistic quantum Lenoir engine has been conducted. Initially, we analogize the quantum working substance of the engine, a massless boson trapped in an infinite potential box with a movable right wall, as an ideal gas confined in a pistoned cylinder. Then, the total work, heat input, and heat output of each engine cycle which consists of isochoric, adiabatic expansion, and isobaric compression are extracted by applying the concept of quantum thermodynamics. Finally, power output, thermal efficiency, and reversibility rate of the engine are calculated for different variations of the heat leakage constant. The results are the relationship between several parameters which are expressed in the graph of thermal efficiency vs. compression ratio, graph of efficiency/normal efficiency vs. compression ratio, power output vs. efficiency, and reversibility rate vs. compression ratio. The conclusion is that an increase in heat leakage has an effect on reducing the efficiency and reversibility rate of the engine but does not affect its power output. This work will provide a new chapter for further research related to the use of the boson particle as a working substance in the quantum heat engine, especially the study of the heat leakage effect on engine performance.
Co-Authors Abdul Waris Al-Zairi, Achmad Amelia, Rani Marizah Budi Prayitno Firdaus, Rohim Aminullah Jefri Pandu Hidayat Mahera, Adinda Kholif Mayantasari, Menasita Musyarofah Musyarofah Musyarofah Musyarofah, Musyarofah Nurhayati Nurhayati Puspitasari, Nurrisma Salsabila, Syifa Saputra, Yohannes Dwi shoodiqin, dian mart Yohanes Dwi Saputra, Yohanes Dwi