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Electrical Insulation, IEEE Transactions on

Issue 5 • Date Oct 1988

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  • The dielectric relaxation spectra of water, ice and aqueous solutions, and their interpretation. II. Tentative interpretation of the relaxation spectrum of water in the time and frequency domain

    Publication Year: 1988 , Page(s): 817 - 823
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (392 KB)  

    For pt.I see ibid., vol.23, no.5, Oct. 1988, p.801-16. A qualitative discussion on the relaxation spectrum of water in the time and frequency domains is presented. According to the picture that emerges, quantum jumps, induced by thermal phonon excitation in the near infrared, disconnect water dipoles sufficiently from their surroundings to allow reorientation of these dipoles and a subsequent reorganization of their near-surroundings. In an applied electric field, these jumps can be measured as polarization spike signals in the time domain. The statistical correlation time between the consecutive jumps of the same water molecule determines the relaxation time τ in the frequency domain. With increasing temperature, the statistical average of the required activation energy moves from the intramolecular into the intermolecular region, and the effect deuterium substitution on vibration frequency and τ consequently falls from the mass ratio √D/H toward √D2O/H2O View full abstract»

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  • The dielectric relaxation spectra of water, ice, and aqueous solutions, and their interpretation. III. Proton organization and proton transfer in ice

    Publication Year: 1988 , Page(s): 825 - 840
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (924 KB)  

    For pt.II see ibid., vol.23, no.5, Oct. 1988, p.817-23. After a short presentation of the various ice phases and of the oxygen sublattices for ice I, the proton array of ice I is considered, simple approximate derivation of the zero-point entropy for random distribution given, and evidence examined from some proton ordering along the hexagonal axis of ice Ih. Next, the experimental facts are summarized on orientation polarization and conduction, and N. Bjerrum's ideas (1951) are given about defect-pair and ion-pair formation. The double-well model for polarization and conduction in ice, is used to describe the behavior of the individual defects and ions, after the pairs have formed, drifted apart, and settled down. The author argues that this model seems in conflict with the observed dielectric relaxation time when the proper activation energy is used. Therefore, another model is presented, linking the formation and separation of defects to the dielectric relaxation spectrum and to infrared spectroscopy View full abstract»

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  • High-voltage vacuum insulation-new horizons (1988 Whitehead Memorial Lecture)

    Publication Year: 1988 , Page(s): 881 - 894
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (976 KB)  

    It is well established that the insulating capability of a high-voltage (HV) vacuum gap is ultimately limited by electrode surface processes, in particular by the field-induced emission of electrons from anomalous microscopic `sites' that occur randomly on an electrode surface. The author reviews the fundamental studies that have led to an understanding of this phenomenon. Issues discussed are the location and identification of electron emission sites. The emission characteristics of sites; and the emission mechanism. The author concludes with a discussion of the technological implications of his knowledge, particularly in relation to the many emerging applications associated with the development of space-based power systems View full abstract»

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  • Kerr electro-optic field mapping measurements in electron-beam irradiated polymethylmethacrylate

    Publication Year: 1988 , Page(s): 861 - 880
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1172 KB)  

    To understand electron-caused discharges along insulating solid surfaces on spacecraft as well as in solids, Kerr electro-optic field mapping measurements have been performed in electron-beam-irradiated polymethylmethacrylate. The accumulated trapped charge results in large self-electric fields of the order of 1 to 3.5 MV/cm. Measurements were done at electron-beam energies up to 2.6 MeV at low (20 nA/cm2) and high (300 nA/cm2) current densities and for sample thickness of 0.635, 0.95, 1.27 and 2.54 cm. It was found that volume breakdown through the electron charged region may occur spontaneously when accumulated charge levels are high. Typically at breakdown the net charge density magnitude exceeded 1 μC/cm2 and internal fields exceeded 1.8 MV/cm. Charge dynamics during electron-beam irradiation was also analyzed on the basis of a simple model consisting of the continuity and Poisson's equations including charge generation and radiation-induced conductivity View full abstract»

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  • The contributions of Arthur Robert von Hippel to electrical insulation research

    Publication Year: 1988 , Page(s): 791 - 800
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (988 KB)  

    The life and career of Prof. Arthur Robert von Hippel are reviewed. It is noted that he founded the Laboratory for Insulation Research at MIT in 1940, pioneering in materials research, measurements, and instrumentation evolving to the present-day MIT Center for Materials Science and Engineering and to the MIT Laboratory of Electromagnetic Electronic Systems. Particular attention is given to his conception that it may be possible to use atoms as building blocks for design purposes, with physicist as architect View full abstract»

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  • The dielectric relaxation spectra of water, ice, and aqueous solutions, and their interpretation. I. Critical survey of the status-quo for water

    Publication Year: 1988 , Page(s): 801 - 816
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (968 KB)  

    A summarizing critical analysis is given of the present understanding of the dielectric relaxation spectrum of pure water. The author starts with a classical description of this spectrum and proceeds through the various molecular interpretations by electrostatic models (Debye, Onsager, Kirkwood, Lennard-Jones, and Pople) and by dynamic-statistical models, including their relations to infrared spectroscopy. It is concluded that there is at present no valid theory for the static permittivity or for the relaxation time View full abstract»

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Aims & Scope

This Transactions ceased production in 1993. The current retitled publication is  IEEE Transactions on Dielectrics and Electrical Insulation.

Full Aims & Scope