89 research outputs found
Electronic transport in disordered n-alkanes: From fluid methane to amorphous polyethylene
We use a fast Fourier transform block Lanczos diagonalization algorithm to study the electronic states of excess electrons in fluid alkanes (methane, ethane, and propane) and in a molecular model of amorphous polyethylene (PE) relevant to studies of space charge in insulating polymers. We obtain a new pseudopotential for electron–PE interactions by fitting to the electronic properties of fluid alkanes and use this to obtain new results for electron transport in amorphous PE. From our simulations, while the electronic states in fluid methane are extended throughout the whole sample, in amorphous PE there is a transition between localized and delocalized states slightly above the vacuum level (∼+0.06 eV). The localized states in our amorphous PE model extend to −0.33 eV below this level. Using the Kubo–Greenwood equation we compute the zero-field electron mobility in pure amorphous PE to be μ≈2×10−3 cm2/V s. Our results highlight the importance of electron transport through extended states in amorphous regions to an understanding of electron transport in PE.EPSRC through Grants No.GR/R18222 and No. GR/M9442
Space charge and charge trapping characteristics of cross-linked polyethylene subjected to ac electric stresses
The Thermal Step Method Applied to Surface Charge Detection and to the Study of Flashover Initiation
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The Thermal Step Method Applied to Surface Charge Detection and to the Study of Flashover Initiation
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The Thermal Step Method for Space Charge Measurements under Applied dc Field
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Recent Advances in Calculating Space Charge Distribution by Processing the Signals Obtained Using the Thermal Step Method
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Recent Advances in Calculating Space Charge Distribution by Processing the Signals Obtained Using the Thermal Step Method
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Etude des charges d'espace dans l'isolant des câbles de transport de l'énergie
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Electrical double layer at dielectric liquid/solid interface. Space charge measurements using the thermal step methods
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