JPS6226707B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in data processing devices for process gas chromatographs.

In a typical gas chromatograph, samples can be analyzed without changing columns. Therefore, the waveforms corresponding to the components temporally separated and discharged by the column are output in descending order of peak value as shown in FIG. In other words, the signals are output in descending order of concentration, and as the time from the sample input time T ₀ becomes longer, the peak value of the waveform gradually becomes smaller, and the slope of its rise and fall also becomes gentler.

The amount of each component separated in time is shown in each waveform A,
It is obtained by integrating the areas of B and C. To detect the start and end points of this area integration, for example, differentiate the waveforms A, B, and C at regular time intervals, find the difference between the previous differential value and the next differential value, and find the difference between the previous differential value and the next differential value. Detection is performed based on the state in which the temperature is lower than a predetermined value and the state in which it is below a predetermined value. If the detection sensitivity for detecting the integration start and end points is set to a constant value, as explained earlier, the characteristics of the waveform output later will gradually become looser, so the integration start and end points will be Detection will not be performed properly.
For example, integration is performed as shown with diagonal lines in FIG. 2, which has the drawback of deteriorating analysis accuracy.

For this reason, conventionally, as shown in FIG. 3, the differential detection sensitivity is increased with the passage of time, thereby improving the analysis accuracy.

By the way, in process gas chromatographs, components are separated by switching columns in order to shorten analysis time. For this reason, the separated waveforms A, B, and C are, for example, A, B, and C as shown in FIG.
The order of C and B is usually different from that of a normal gas chromatograph. Therefore, in the case of a process gas chromatograph, it is not possible to uniquely increase the detection sensitivity for detecting the integration start and end points over time.

An object of the present invention is to provide a data processing device that can detect the integration start and end points of a separated waveform of a process gas chromatograph at appropriate positions.

This invention focuses on the fact that the separated waveform output from the process gas chromatograph is extracted by a gate signal with a predetermined time width, and the detection sensitivity is set in proportion to the time width of this gate signal. This is what I did.

That is, in the process gas chromatograph, as shown in FIG. 4, noise signals N ₁ and N ₂ are generated between the separated waveforms A, C, and B because columns and the like are switched. Therefore, if the separated waveform of the process chromatograph is supplied as is to the integrating means, the data processing device will also integrate the noise signals N ₁ and N ₂ , resulting in the inconvenience of outputting data that can easily be mistaken for component quantities.
For this reason, we focused on the fact that conventionally each separated waveform A, C, B is output at a predetermined time from sample input, and the output order of each component is also predetermined.
Gates are provided to take out the separated waveforms A, C, and B, and the gates are controlled to open at predetermined times _ta , _tc , and _tb , and as a result, the separated waveforms A, I try to extract only C and B. The gate time width is set in proportion to the spread of the bottom of the separated waveform, and the gate time is set to become longer as the waveform has a gentler characteristic.

Therefore, in the present invention, the detection sensitivity is set in proportion to the gate time width, and one embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 5 shows an embodiment of the present invention. 51 in the diagram
1 shows the entire data processing device. 512 is an input terminal of this data processing device 511, and to this input terminal 512, for example, separated waveforms A, C, and B of each component as shown in FIG. 4 are inputted from a gas chromatograph (not particularly shown). do. Separated waveform A of each component supplied to input terminal 512,
C and B are supplied to gate means 513. A gate signal is supplied to this gate means 513 from a gate signal source 514 . The time width of the gate signal source 514 is defined by data read from the gate time width memory 515. A read operation of gate time width storage 515 is performed in response to a gate start signal from gate start time storage means 516. Note that 517 is a memory device 515, 516
A setting device for setting an appropriate value is shown below.

The separated waveforms A, C, and B gated and extracted by the gate means 513 are sent to the integrating means 518, the integration start point detection means 519, and the integration end point detection means 521.
supply to.

In this invention, gate time width data is provided from the gate time width memory 515 to the slope detection sensitivity setting means 522, and a detection sensitivity proportional to the gate time width is set. This slope detection sensitivity setting means 52
The detection sensitivity set in step 2 is applied to the detection sensitivity integration start point detection means 519 and the integration end point detection means 521, and the detection sensitivity is changed in proportion to the gate time width.

The gate time start memory 516 includes a clock device 52.
3 provides time data from the time of sample input, and when the time data matches, for example, the gate start time of the first component, a read signal is provided to the gate time width memory 515. In response to this read signal, the gate time width memory 515 outputs the preset time width data of the first component. Based on this time width data, the gate signal generator 514 outputs a gate signal having a predetermined time width from the gate start time of the first component to open the gate means 513, during which time the separated waveform A of the first component is passed through, and the integration means The separated waveform A is given to 518, integration start point detection means 519, and end point detection means 521.

Integration start point detection means 519 and end point detection means 5
21 is given the detection sensitivity data set in the sensitivity setting device 522, and is set to a detection sensitivity proportional to the gate time width of the gate means 513. In this way, the detection sensitivities of the integration start and end points for each of the separated waveforms C and B are set in proportion to the gate time width.

Therefore, when the gate time t _c is long as in separated waveform C, the detection sensitivity is set proportionally higher, so even if the rise and fall characteristics are slow, the rise and fall are appropriate. The start and end of integration can be detected at points.

Therefore, according to the present invention, the order of separated waveforms is
As shown in the figure, even if there is no unambiguous tendency in which the rise and fall characteristics gradually become looser with the passage of time, it is possible to set an appropriate detection sensitivity for each separated waveform. Therefore, the analysis accuracy of process gas chromatographs can be greatly improved, and the effect is great in practical use.

In FIG. 5, reference numeral 524 denotes a next component gate monitor which sets the gate time start memory 516 to a standby state based on the integration end detection signal.

[Brief explanation of the drawing]

Figure 1 is a waveform diagram showing the separation waveform of a normal gas chromatograph, Figure 2 is a waveform diagram to explain the integration situation when the integration start sensitivity of that waveform is set to a constant value, and Figure 3 is a waveform diagram of the normal gas chromatograph. A graph for explaining the sensitivity control characteristics of the integration start point and end point in a gas chromatograph, FIG. 4 is a waveform diagram showing an example of a separation waveform of a process gas chromatograph, and FIG. 5 is a system showing an example of the present invention. It is a diagram. 513: Gate means, 514: Gate signal generator, 515: Gate time width memory, 516: Gate time start memory, 518: Integrating means, 519:
Integration start point detection means, 521: Integration end point detection means, 522: Time measurement means.

Claims (1)

[Claims] 1. In a process gas chromatograph data processing device that performs area integration from each start point to end point of each outflow component waveform of a process gas chromatograph, means for storing gate start time and gate width for each component, and means for storing gate start time and gate width for each component. means for setting a slope detection sensitivity determined by the gate width, and a waveform start for each component corresponding to a setting value set in the slope detection sensitivity setting means corresponding to the gate width at each gate start time; A start point detection means and an end point detection means for detecting points and end points, and integrating the area between the start point and the end point of the waveform detected by the start point detection means and the end point detection means for each component. A process gas chromatograph data processing device comprising: