THE COMPLEX DIELECTRIC CONSTANT AT LOW MICROWAVE FREQUENCIES OF ETHYL CHLORIDE ADSORBED ON POROUS VYCOR GLASS

1961 ◽  
Vol 39 (3) ◽  
pp. 425-442 ◽  
Author(s):  
J. D. McCowan ◽  
R. McIntosh
Keyword(s):  
Dielectric Constant ◽  
Coaxial Line ◽  
Ethyl Chloride ◽  
Complex Dielectric Constant ◽  
Frequency Range ◽  
Vycor Glass ◽  
Microwave Frequencies ◽  
The Real ◽  
Porous Vycor Glass ◽  
Accuracy Of Measurement

The complex dielectric constant of the system Vycor glass – ethyl chloride has been measured at three temperatures in the range +11 °C to −33 °C and in the frequency range between 500 Mc sec−1 and 4000 Mc sec−1 by the use of a coaxial line. The real and imaginary parts of the dielectric constant of the adsorbate have also been evaluated. Appreciable loss in the adsorbed matter is found for small quantities adsorbed, and loss is again detected at the highest frequencies and lowest temperatures for the matter held in multilayers or condensed in capillaries. The frequency range and accuracy of measurement were not sufficient to classify the type of loss curve, but other evidence suggests that the loss for the first quantities adsorbed will turn out to be that for rotational oscillators. In general earlier observations of this system are confirmed and extended.

THE DIELECTRIC CONSTANT OF BROMINE AT MICROWAVE FREQUENCIES

1967 ◽  
Vol 45 (7) ◽  
pp. 2349-2354 ◽  
Author(s):  
I. R. Dagg ◽  
G. E. Reesor ◽  
R. P. Doble
Keyword(s):  
Dielectric Constant ◽  
Loss Tangent ◽  
Optical Range ◽  
Frequency Range ◽  
Improved Method ◽  
Microwave Frequencies ◽  
The Real ◽  
Liquid Bromine ◽  
Tan Δ

Measured values of the real part of the dielectric constant, ε′, and the loss tangent, tan δ, of liquid bromine at 20 °C in the frequency range 8.2–18 GHz are presented. The results for tan δ were obtained by a previously described technique; the results for ε′ were obtained by an improved method herein described. A suggested mechanism for absorption is discussed and the results related to static values and values in the optical range.

The complex dielectric constant of snow at microwave frequencies

1984 ◽  
Vol 9 (5) ◽  
pp. 377-382 ◽  
Author(s):  
M. Tiuri ◽  
A. Sihvola ◽  
E. Nyfors ◽  
M. Hallikaiken
Keyword(s):  
Dielectric Constant ◽  
Complex Dielectric Constant ◽  
Microwave Frequencies

THE COMPLEX DIELECTRIC CONSTANT OF SOLUTIONS OF TRIMETHYLPENTANE AND NITROBENZENE NEAR THE CONSOLUTE TEMPERATURE

1961 ◽  
Vol 39 (3) ◽  
pp. 526-534 ◽  
Author(s):  
B. D. Ripley ◽  
R. McIntosh
Keyword(s):  
Dielectric Constant ◽  
Phase Separation ◽  
Standing Wave ◽  
Applied Field ◽  
Coaxial Line ◽  
Dielectric Constants ◽  
Complex Dielectric Constant ◽  
Experimental Procedure ◽  
Chemical Systems ◽  
Consolute Temperature

The complex dielectric constants of three compositions of trimethylpentane and nitrobenzene have been measured as a function of temperature for a range near the consolute temperature. The frequency employed was 3300 Mc/sec. The experimental procedure involved the study of the standing wave established in a coaxial line. The chemical systems showed maxima in both the real and imaginary parts of the complex dielectric constant at temperatures above those at which phase separation occurs. The finding of Semenchenko and Azimov is thus confirmed. A discussion of the validity of applying thermodynamic formulae to dielectrics showing loss is given and some qualitative remarks are offered concerning the change of the systems as they are cooled. These remarks are based upon the effect of the applied field upon the entropy of the solutions.

scholarly journals Relaxation Dynamics of Ethanol and N-Butanol in Diesel Fuel Blends from Terahertz Spectroscopy

2021 ◽  
Vol 42 (7) ◽  
pp. 772-792
Author(s):  
Rayda Patiño-Camino ◽  
Alexis Cova-Bonillo ◽  
José Rodríguez-Fernández ◽  
Teresa P. Iglesias ◽  
Magín Lapuerta
Keyword(s):  
Dielectric Constant ◽  
Relaxation Time ◽  
Full Range ◽  
Pure Component ◽  
Complex Dielectric Constant ◽  
Relaxation Processes ◽  
Relaxation Dynamics ◽  
Terahertz Time Domain Spectroscopy ◽  
Ideal Behavior ◽  
The Real

AbstractBinary blends of ethanol-diesel, n-butanol-diesel, ethanol-biodiesel, and n-butanol-biodiesel have been analyzed with terahertz time-domain spectroscopy in a full range of concentrations and at room temperature. The real and imaginary parts of the complex dielectric constant of the blends were obtained from the spectra and fitted to the Debye model at low volume concentrations (up to 7.5% for ethanol in diesel and up to 20% for butanol in diesel, ethanol in biodiesel, and butanol in biodiesel blends), considering the number of relaxation processes recommended in the literature for each pure component (single for diesel, double for biodiesel, and triple for alcohols). The results indicate that the faster relaxation time in low alcohol mixtures is longer than in pure alcohols. This relaxation time increases as the alcohol content increases. The excess of the real and of imaginary parts of the dielectric constant were individually determined. The analysis of such excess and of its different contributions (volume, contrast, and interactions) suggests that the intermolecular interactions between the different components of the blends dominate the relaxation dynamics in each pseudo-binary system. Ethanol was found to move blends further away from ideal behavior than n-butanol. In fact, these latter blends showed the most ideal behavior, suggesting that the length of the alcohol carbon chain plays an important role. This information allows a possible link between the nonlinear behavior of the physicochemical properties of the blends (e.g., viscosity and surface tension) and the molecular interactions between their constituent molecules. This relation could have direct application for monitoring the fuel composition and quality in the vehicle control systems.

scholarly journals PENGUKURAN NILAI DIELEKTRIK MATERIAL CALCIUM COPPER TITANAT ( CaCu3Ti4O12) MENGGUNAKAN SPEKTROSKOPI IMPEDANSI TERKOMPUTERISASI

2017 ◽  
Vol 6 (1) ◽  
pp. 26
Author(s):  
Widodo Budi Kurniawan
Keyword(s):  
Dielectric Constant ◽  
Impedance Spectroscopy ◽  
Ceramic Materials ◽  
Complex Dielectric Constant ◽  
Frequency Range ◽  
Frequency Dependent ◽  
Calcium Copper Titanate ◽  
Ccto Sample

Telah dilakukan pengukuran tetapan dielektrik kompleks dan besarnya impedansi kapasitor pada material keramik Calcium Copper Titanate dengan struktur material CaCu3Ti4O12 (CCTO) dengan kemurnian 99 % menggunakan metode spektroskopi impedansi terkomputerisasi dalam rentang frekuensi 5 kHz – 120 kHz. Tetapan dielektrik maksimum terukur pada sampel yang disintering dengan suhu 7000C yaitu 745 pada frekuensi 5 kHz dan besarnya impedansi kapasitor maksimum terjadi pada sampel CCTO non sintering yaitu 150434 Ω. Hasil penelitian menunjukkan adanya pengaruh frekuensi terhadap tetapan dielektrik kompleks dan impedansi kapasitor dari material yang diteliti. Kata kunci : spektroskopi impedansi, CaCu3Ti4O12, tetapan dielektrik kompleks dan impedansi kapasitor.   MEASUREMENT OF THE DIELECTRIC CONSTANT CALCIUM COPPER TITANATE (CaCu3Ti4O12) MATERIALS USING COMPUTERIZED IMPEDANCE SPECTROSCOPY  ABSTRACT The measurement of the complex dielectric constant and the magnitude of the capacitor impedances of the ceramic materials Calcium Copper Titanate CaCu3Ti4O12 (CCTO) with purity of 99% has been done by using the method of computerized impedance spectroscopy in the frequency range 5 kHz - 120 kHz. The highest dielectric constant of the material was found to be 745 at 5 kHz in the sample sintered 7000C and the highest impedance of capacitor occured in CCTO sample non sintered that is 150434Ω. The results showed that complex dielectric constant and impedance of the capacitor of the material under study was frequency dependent. Keywords : impedance spectroscopy, CaCu3Ti4O12,complex dielectric constant and impedance of capacitor

DIELECTRIC RELAXATION IN CLAYS SATURATED WITH WATER-OIL EMULSION IN A WIDEBAND OF FREQUENCIES AT POSITIVE AND NEGATIVE TEMPERATURES

2021 ◽  
pp. 96-108
Author(s):  
A. V. Repin
Keyword(s):  
Dielectric Constant ◽  
Wide Frequency Range ◽  
Complex Dielectric Constant ◽  
Relaxation Processes ◽  
Frequency Range ◽  
Water Emulsion ◽  
Oil Emulsion ◽  
Negative Temperatures ◽  
Oil Water ◽  
Account Relaxation

The results of measuring the complex dielectric constant of clays saturated with an oil-water emulsion in various ratios in a wide frequency range are presented. The measurements were used out at positive and negative temperatures. It was revealed that several relaxation processes are observed in the spectra. The processes parameters significantly depend on the temperature and the ratio of water and hydrocarbon to the saturating mixture. A model is proposed that makes it possible to take into account relaxation processes and their dependence on temperature.

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