ISSN:
1572-9567
Keywords:
cyclohexane
;
dielectric constant
;
re-entrant radio-frequency resonator
;
relative permittivity
;
static dielectric constant
;
water
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract The complex dielectric constant (relative electric permittivity) $$\varepsilon _{\text{r}} = \varepsilon ' - i\varepsilon ''$$ of liquid water was redetermined in the temperature range 0°C〈;t〈145°C at pressures less than 440 kPa. In this work, εr was deduced from measurements of the resonant frequencies f α of a novel, re-entrant, two-mode, radio-frequency resonator. The frequencies ranged from 23 to 84 MHz and were well within the low-frequency limit for ε′ because (2πf ατmax)2〈5×10−5 where τmax=1.8×10−11 s is the maximum relaxation time of water under the conditions studied. The data for ε′ for two water samples differing in conductivity by a factor of 3.6 and for the two resonant modes differing in frequency by a factor of 2.6 were simultaneously fit by the polynomial function ε′(t)=87.9144−0.404399t+9.58726×10−4 t 2−1.32802×10−6 t 3 with a remarkably small residual standard deviation of 0.0055. The present data are consistent with previously published data; however, they are more precise and internally consistent. The present apparatus was also tested with cyclohexane and yielded the values ε′(t)=2.0551−0.00156t for 20°C〈t〈30°C, in excellent agreement with previously published values.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1021979401680
