Surface and Quantum Effects in Nanosized Semiconductor
Augustine Ike Onyia,
Henry Ifeanyi Ikeri,
Abraham Iheanyichukwu Chima
Issue:
Volume 8, Issue 3, September 2020
Pages:
35-41
Received:
29 July 2020
Accepted:
11 August 2020
Published:
19 August 2020
Abstract: Novel properties of nano-scale semiconductors based on the surface and quantum effects have been studied and applications identified. Spherical potential well model is used to study quantum effect whereas basic geometrical models are used for the surface effect. We have shown such effects to be the fundamental factors responsible for the novel nanosized semiconductor characteristics different from the bulk of same material. It is found that the surface area to volume ratio follows inverse power law. Thus at nanoscale, the surface to volume ratio increases significantly to enhance chemical reactivity. In addition, the increased surface area makes most nananocrystals highly soluble in liquid and dramatically lowers their melting temperature. The result strongly suggests also that the shape of the nanoparticles influences the surface area which has huge impact on their properties and performance. Our results of quantum size effect reveal that spatial confinement of charge carriers within semiconductor nanocrystals significantly modulates their properties such as size dependent absorption and emission spectra with non-zero discrete electronic transition energies as well as their blue shift band gaps. Thus by changing the size of the particle, we can literally fine-tune a material property of interest such as optical, electrical, and surface area. Specifically we found that InAs and InSb nano semiconductor optical absorption spectrum, in contrast to their bulk, can be tuned in broad range of UV to IR regions which are favorable operating wavelengths for nano photonic technology such as IR photo detectors and full spectrum solar cells applications.
Abstract: Novel properties of nano-scale semiconductors based on the surface and quantum effects have been studied and applications identified. Spherical potential well model is used to study quantum effect whereas basic geometrical models are used for the surface effect. We have shown such effects to be the fundamental factors responsible for the novel nano...
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Estimation of the Calorific Value and Electrical Energy Potential of Waste Generated Biomass Within Abakaliki Meteropolis Ebonyi State, Nigeria
Igbo Micheal Elem,
Chikeleze Praise Chukwuemeka,
Augustine Ike Onyia,
Igbo Nkechinyere Elem,
Eze Calister Ngozi,
Chima Abraham Iheanyichukwu
Issue:
Volume 8, Issue 3, September 2020
Pages:
42-49
Received:
20 August 2020
Accepted:
31 August 2020
Published:
14 September 2020
Abstract: This study was conducted to determine the electrical energy potential of municipal solid waste (MSW) generated biomass within Abakaliki metropolis, Ebonyi State, Nigeria. The MSW samples were collected at two different points from each of the waste management zones, with each zone covering at least twelve (12) streets. It was then sorted into three major categories according to their constituents viz; metals, plastics and biomass. In this study, the biomass component of the MSW sample was is our focus. Thus, the biomass sample was sun dried and then ground into powdered form. It was thoroughly mixed, shredded, sieved and subsequently analysed at the Lorcin Technologies Port Harcourt, Nigeria. Currently, an average of 360 tons of MSW is generated within Abakaliki metropolis on daily bases. This translates to an electrical energy potential of approximately 320MW. The MSW-generated biomass analysis estimates the Gross Calorific Value (GCV) or Higher Heating Values (HHV) to be 11.644MJ/kg. This value which practically determines the electrical energy of the waste sample is highly suitable for many thermal conversion processe. This translate to the fact 0.925kg of biomass will generate electrical power of 1KWh. Hence, one unit of electricity=10765KJ/Kg/GVC (KJ/Kg).
Abstract: This study was conducted to determine the electrical energy potential of municipal solid waste (MSW) generated biomass within Abakaliki metropolis, Ebonyi State, Nigeria. The MSW samples were collected at two different points from each of the waste management zones, with each zone covering at least twelve (12) streets. It was then sorted into three...
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Influence of Metallic Copper Vapors on the Chemical Composition of a Mixture of Air and Water Vapor Thermal Plasmas in the Temperature Range 1000 K to 20000K
Kohio Nièssan,
Kagoné Abdoul Karim,
Yaguibou Wêpari Charles,
Koalaga Zacharie,
Zougmoré François
Issue:
Volume 8, Issue 3, September 2020
Pages:
50-57
Received:
18 August 2020
Accepted:
18 September 2020
Published:
12 October 2020
Abstract: This paper concern the calculation of equilibrium composition of plasma mixture Air-Water vapor and copper vapor in temperatures range 1000K to 20000 K. The plasma is suposed to be in local thermodynamic equilibrium. We used Gibbs free energy minimization method to access the different numerical densities of chemical species as a function of temperature. This data are very important to calculate thermodynamic properties, transport coefficients and modeling electrical arc in circuit breakers. The result shows that the influence of metallic copper vapor is important on equilibrium composition of plasma. In particular the densities of electron in the plasma increase with the percentage of copper vapor for the temperature inferior to 17000K. The increasing of electron densities increase electrical conductivity of plasma and limit the performance of circuit breakers. Also the electrical neutrality is made mainly between electron (e-) and Cu+ in low temperature (T < 12000K). We are studying in particular the evolution of the densities of the main chemical species created in this plasma as a function of pressure. We choose four values of pressure (1 atm, 5 atm, 10 atm and 15 atm). The results obtained shows an increasing of chemical densities with the pressure in the mixture in conformity at Dalton's Law. the increasing of the pressure in the plasma retard chemical reactions because it disadvantages the dislocations that constitute dissociation and ionization reactions in the plasma.
Abstract: This paper concern the calculation of equilibrium composition of plasma mixture Air-Water vapor and copper vapor in temperatures range 1000K to 20000 K. The plasma is suposed to be in local thermodynamic equilibrium. We used Gibbs free energy minimization method to access the different numerical densities of chemical species as a function of temper...
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