SU544975A1 - Device for determining the area of the chromatographic peak - Google Patents

Description

one

The invention relates to the field of computer technology and is especially demanding for use in automated chromatographic information processing systems.

A device for determining the area of the chromatographic peak containing the peak boundary determining blocks and integration blocks is known. 1.

However, such a device does not provide an accurate definition of the limits of integration, since near the zero line of the chromatogram, the signal of the chromatograph is distorted by noise, making it difficult to accurately determine the boundaries of the peak.

It is also known to have a device 2 comprising blocks of subtraction, comparison, memory, triggers, a reversible counter and an integral counter.

The disadvantage of this device is the complexity of the constructive implementation.

The prototype of the invention is a device for determining the area of the chromatographic peak 3, which contains a peak amplitude measurement unit, connected to the input to the device, and the output to the first input of the duplication unit.

This device has the disadvantage of not taking into account changes in the actual width of the peak relative to the calibration width, which leads to an error

when processing the results of chromatographic analysis.

The purpose of the invention is to improve the accuracy of determining the area of the chromatographic peak.

This is achieved by additionally introducing an exponential voltage driver, a square root extractor and a time interval measurement unit connected by an output through a square root extractor to the second input of the duplication unit and connected by a first input to the device input and a second input through the exponential voltage driver with the output of the peak amplitude measurement unit.

The drawing shows the block diagram of the device.

The device consists of a peak amplitude measurement unit 1; an exponential voltage driver 2 connected by the input to block 1, and an output to block 3 for measuring the time interval, with inputs 1 and 3 connected to the input of the device; a square root extraction unit 4, through which the output of block 3 is connected to one of the inputs of the copying unit 5, the other input connected to the output of block 1.

The device works in the following way.

The signal from the chromatograph, which represents the robust peak of the sensor, which is approximated with great accuracy by the Gauss curve, goes to the peak amplitude measurement unit 1. This block stores the measured amplitude value and transmits this value to exponential voltage generator 2 and multiplication unit 5. From this moment on, the formation of exponential voltage begins.

This voltage is applied to the input of block 3, at the output of which a time interval is formed, starting at the moment of starting the exponential voltage and ending at the instant of equality of the instantaneous values of the voltages of the exponent and the chromatographic peak. Unit 4 performs a square root extraction operation from the measured time interval and gives the result to another input of the multiplying unit 5, the output of which is a value equal to the area of the chromatographic peak.

The proposed device also makes it possible to determine the areas of the combined peaks. If the time constant of the exponent is chosen depending on the degree of combining determined in advance, so that the time of the end of the time interval corresponds to the undistorted (due to superposition) values of the chromatogram, then the output areas of the device are the true peak areas.

The accuracy of the chromatographic analysis results obtained when using this device in the chemical and petrochemical industries leads to an increase in the quality of products and savings in raw materials.

Claims (3)

1.Avt. St. No. 415677, cl. G 06J 3/00, 1972. 2. Avt. St. No. 443249, cl. G 06J 3/00, 1972. 3. Avt. St. No. 187661, cl. G 01N 31/08, 1963 (prototype). From hro.