Boris A. Gurovich; Denis A. Kuleshov; Dmitriy A. Maltsev; Oleg K. Chugunov; Alexey S. Frolov; Yaroslav I. Shtrombakh
Abstract
The operation of nuclear graphite in graphite-moderated reactors is accompanied by its properties degradation under the influence of neutron irradiation, which limits their service life. In this connection, it is of interest to identify the mechanisms that determine the properties degradation of graphite ...
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The operation of nuclear graphite in graphite-moderated reactors is accompanied by its properties degradation under the influence of neutron irradiation, which limits their service life. In this connection, it is of interest to identify the mechanisms that determine the properties degradation of graphite materials at various operational stages of operating RBMK power reactors.
Carmen G. Renda; Jeferson A. Dias; Roberto Bertholdo; Alessandra A. Lucas
Abstract
The phenolic resin (PR) is widely studied as matrix for composites due to its promising mechanical properties and chemical stability. However, which regard to electrical conduction, PR is a typical insulator (electrical conductivity around 10 -12 S.cm -1 ), limiting its utilization for electric ...
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The phenolic resin (PR) is widely studied as matrix for composites due to its promising mechanical properties and chemical stability. However, which regard to electrical conduction, PR is a typical insulator (electrical conductivity around 10 -12 S.cm -1 ), limiting its utilization for electric conduction’ applications. Expanded graphite (EG) and conductive carbon black (CB) are fillers that have been utilized to increase the electrical conductivity of several polymers, but they have not yet been enough studied to composites materials with PR. Thus, this study aims at asses to produce composites of PR and EG or CB (2% w / w) and verify the influence these fillers on the composites’ electrical properties. The composites were analyzed by FT-IR (Fourier Transform-Infrared Spectroscopy), Impedance Spectroscopy (IS) and Scanning Electron Microscopy (SEM). It was verified that the electric conductivity of the PRs increased due to fillers. The composite PR/CB showed electric conductivity about five orders of magnitude higher than the PR. On the other hand, the composite PR/EG showed greatest electrical conductivity, about seven orders of magnitude higher than the PR (1.1x10 -5 S.cm -1 ). These results have shown the efficacy of those fillers in the increase of the electrical conduction in PR-based composites. Therefore, these composites materials have potential to be used as Electromagnetic Interference (EMI) shielding and electrostatic discharge (ESD).
Muhammad Asghar; Ya Hong Xie; M. Asif Nawaz; Hammad M. Arbi; M. Y. Shahid; F. Iqbal; Waqas Khalid
Abstract
Doping is a notable factor to improve the performance of CdTe/CdS heterojunction solar cell. Graphite doped CdTe/CdS heterojunction on Si (1 1 1) substrate has systematically fabricated by thermal evaporator method under medium vacuum (10 -4 torr) condition. Characterization of doped CdTe/CdS film ...
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Doping is a notable factor to improve the performance of CdTe/CdS heterojunction solar cell. Graphite doped CdTe/CdS heterojunction on Si (1 1 1) substrate has systematically fabricated by thermal evaporator method under medium vacuum (10 -4 torr) condition. Characterization of doped CdTe/CdS film was carried out by various diagnostic techniques such as X-ray diffraction (XRD) exhibits the polycrystalline structure of cubic phase CdTe and hexagonal phase CdS, scanning electron microscopy (SEM) shows the smoothening of the film, energy dispersive X-ray (EDX) confirm the elemental composition found in the film and current-voltage (I-V) analysis suggests the diode like properties where the current is slightly increased by the doping of graphite into CdTe/CdS heterojunction compared to the reported literature. Analysis of I-V characteristics has been made to investigate the current conduction mechanism in CdTe/CdS heterojunction.
Srinivasarao Yaragalla; Gopinathan Anilkumar; Vineeshkumar T. V.; Nandakumar Kalarikkal; Sabu Thomas
Abstract
Epoxy graphene (EG) was synthesized from graphite (GT) powder using meta chloroperbenzoic acid (mCPBA) as an oxidizing agent at room temperature. Structural properties of the prepared EG were investigated by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy and UV-visible spectroscopy. ...
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Epoxy graphene (EG) was synthesized from graphite (GT) powder using meta chloroperbenzoic acid (mCPBA) as an oxidizing agent at room temperature. Structural properties of the prepared EG were investigated by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy and UV-visible spectroscopy. Results of FT-IR and Raman spectroscopy confirmed that the epoxy groups are incorporated into graphene basal planes. The layered structure of EG was determined using transmission electron microscope (TEM). Optical properties of the prepared EG were analyzed using UV-visible spectroscopy and Photo luminescence (PL) spectroscopy. From the UV-visible spectroscopy data, the band gap of EG was found to be 4.1 eV and this energy gap was roughly correlated with the maximum photoemission behavior of EG and the fluorescence energy was found to be dependent on the excited wavelength. These novel functional materials could be used for applications in the field of opto-electronic and light emitting devices.
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