| dc.creator |
Macdonald J. Ross |
|
| dc.date |
1999 |
|
| dc.date.accessioned |
2013-05-29T23:01:20Z |
|
| dc.date.available |
2013-05-29T23:01:20Z |
|
| dc.date.issued |
2013-05-30 |
|
| dc.identifier |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97331999000200014 |
|
| dc.identifier |
http://www.doaj.org/doaj?func=openurl&genre=article&issn=01039733&date=1999&volume=29&issue=2&spage=332 |
|
| dc.identifier.uri |
http://koha.mediu.edu.my:8181/jspui/handle/123456789/2594 |
|
| dc.description |
Relations and distinctions which are relavant to small-signal electrical-relaxation behavior are reviewed and applied to the important problem of identifying the physical processes leading to dispersed relaxation response. Complex-nonlinear-least-squares fitting of a response model to frequency-response data is found not to allow one to distinguish unambiguously in most cases between conductive-system response of Wagner-Voigt type, which may be characterized by a distribution of conductive system relaxation times [DCRT], and dielectric- system response of Maxwell type, characterized by a distribution of dielectric-system relaxation times [DDRT]. In general, one must include a parallel conductivity element <FONT FACE="Symbol">s</font>CP, as well as a high-frequency-limiting dielectric constant, in a conductive-system fitting model used to represent dielectric-system data with non-zero dc conductivity. Contrary to earlier predictions of Gross and Meixner, accurate numerical inversion of a set of exact frequency- response data to estimate the distribution with which it is associated shows that no discrete line necessarily appears in a DCRT associated with a truncated continuous DDRT. A discrete line can appear in general, however, when <FONT FACE="Symbol">s</font>CP <FONT FACE="Symbol">¹</font> 0 and is unaccounted for in an inversion process. The novel result is established that a data set mathematically described in terms of a dielectric system with dc leakage and involving a Maxwell-circuit exponential distribution of relaxation times may be well represented within usual experimental error by a Wagner-Voigt conductive system involving a form of the important Kohlrausch-Williams-Watts response model. |
|
| dc.publisher |
Sociedade Brasileira de Física |
|
| dc.source |
Brazilian Journal of Physics |
|
| dc.title |
Dispersed electrical-relaxation response: discrimination between conductive and dielectric relaxation processes |
|