Quickly performed measuring method for ascertaining the concentration of the polar components in a material otherwise mainly non-polar

US4233559A · kind A · utility

Assignee

• Bergwerksverband GmbH · DE

Inventors

• Heinz Hoberg · Aachen, DE
• Albert Klein

Key dates

• Filing date: Feb 28, 1979
• Grant date: Nov 11, 1980
• Expiry date: Feb 28, 1999

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R27/28
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Conventionally, the concentration of a polar component in an otherwise non-polar or negligibly polar material, e.g., water content in pourable coal, is ascertained by measuring the attenuation of electromagnetic waves transmitted through a layer-thin sample of the material, the waves having a frequency as near as possible to the maximum-dipole-relaxation-loss frequency f.sub.o, in order to maximize the power-loss effect of the transmitted waves, this being directly attributable to the polar component, and thereby serving to accentuate the effect of the polar component in the measurement signal. The present invention operates at lower frequencies, associated with low dipole-relaxation power-loss, and measures the time delay of the thusly transmitted waves, achieving an unexpected degree of temperature-independence in the measurement signal obtained, and simultaneously, because the power attenuation per unit thickness of the sample is so greatly decreased, making possible the use of samples of unprecedently great thickness, e.g., 1-meter-thick masonry walls whose water content is to be ascertained, compared to the 0.1-meter or 0.2-meter-thick samples to which such techniques have hit…