Method of effecting x-ray analyses

Claim 1

A method of effecting X-ray analysis of a sample containing a specified element, comprising the steps of: a. applying across the anode of an X-ray tube a basic direct current voltage approaching the threshold voltage for the production of X-rays having an energy corresponding to the excitation edge of the element analyzed in the sample, b. superimposing on the said basic direct current voltage a sinusoidal alternating current voltage which, together with the basic direct current voltage, in the positive portions exceeds said threshold voltage, while in the negative portions it lies below said threshold voltage, c. exciting a sample by a beam of X-radiation emitted by the anode of said X-ray tube so that the sample emits fluorescent X-radiation, d. converting within a detector the excited fluorescent Xradiation of the sample into electric current, e. suppressing the direct current component of said current plus the alternating current with the frequency of the superimposed sinusoidal voltage plus the second harmonic of said current, f. amplifying at least one of the higher harmonics of the resulting current, beginning with the third, and g. measuring the amplified current as a measure of the quantity of the specified element contained in the sample.

Claim 2

A method of effecting X-ray analysis of a sample containing a specified element, comprising the steps of: a. applying across the anode of an X-ray tube a basic direct current voltage approaching the threshold voltage for the production of X-rays having an energy corresponding to the excitation edge of the element analyzed in the sample, b. superimposing on the said basic direct current voltage a sinusoidal alternating current voltage which, together with the basic direct current voltage, in the positive portions exceeds said threshold voltage, while in the negative portions it lies below said threshold voltage, c. exciting a sample by a beam of X-radiation emitted by the anode of said X-ray tube so that the sample emits fluorescent X-radiation, d. converting within a detector the excited fluorescent Xradiation of the sample into electric current, e. suppressing the direct current component of said current plus the alternating current with the frequency of the superimposed sinusoidal voltage plus the second harmonic of said current, f. amplifying at least one of the higher harmonics of the resulting current, beginning with the third, and g. measuring the amplified current as a measure of the quantity of the specified element contained in the sample.

Claim 3

A method of effecting X-ray analysis of a sample containing a specified element, comprising the steps of: a. applying across the anode of an X-ray tube a basic direct current voltage approaching the threshold voltage for the production of X-rays having an energy corresponding to the absorption edge of the element analyzed in the sample, b. superimposing on the said basic direct current voltage a sinusoidal alternating current voltage which, together with the basic direct current voltage, in the positive portions exceeds said threshold voltage, while in the negative portions it lies below said threshold voltage, c. passing a beam of X-radiation emitted by the anode of said X-ray tube through the sample into a detector of X-radiation, d. converting the X-radiation in the detector into electric current, e. suppressing the direct current component of said current plus the alternating current with the frequency of the superimposed sinusoidal voltage plus the second harmonic of said current, f. amplifying at least one of the higher harmonics of the resulting current, beginning with the third, and g. measuring the amplified current as a measure of the quantity of the specified element contained in the sample.

Claim 4

A method of effecting X-ray analysis of a sample containing a specified element, comprising the steps of: a. applying across the anode of an X-ray tube a basic direct current voltage approaching the threshold voltage for the production of X-rays having an energy corresponding to the absorption edge of the element analyzed in the sample, b. superimposing on the said basic direct current voltage a sinusoidal alternating current voltage which, together with the basic direct current voltage, in the positive portions exceeds said threshold voltage, while in the negative portions it lies below said threshold voltage, c. passing a beam of X-radiation emitted by the anode of said X-ray tube through the sample into a detector of X-radiation, d. converting the X-radiation in the detector into electric current, e. suppressing the direct current component of said current plus the alternating current with the frequency of the superimposed sinusoidal voltage plus the second harmonic of said current, f. amplifying at least one of the higher harmonics of the resulting current, beginning with the third, and g. measuring the amplified current as a measure of the quantity of the specified element contained in the sample.