SU1105914A1 - Device for correcting base-line of chromatographic signal - Google Patents

Abstract

1. A DEVICE FOR CORRECTING A BASE LINE OF A CHROMATOGRAPHIC SIGNAL containing a voltage-to-frequency converter whose input is the input of the device and the output is connected to the information input of the first key connected by the output to the information input of the threshold unit and the first controlling m input to the output of the code comparison unit connected by inputs to the outputs of the first and second counters connected by summing inputs to the first and second outputs of the first switch, respectively, the first control input of the cat It is connected to the output of the clock generator, characterized in that, in order to improve the accuracy of the baseline correction, an extremum determination unit, second and third switches, second and third keys and an OR element connected by the first input to the first output of the second switch are added to it, the second input to the second output of the second switch, the control input of the second key and the control input to read the second counter, and the output to the zero output inputs, the first control input of the threshold unit and the second control input of the first switch connected by the information input to the output of the third key connected by the information input to the output of the voltage to frequency converter, the input of the extremum determination unit and to the information input of the second key, the first control input to the output of the clock generator and to the second control the first control input and the second control input to the output of the code comparison block and to the second control input of the threshold block connected by the first and second outputs to the first and data inputs of the second switch, respectively, the first control input of which is connected to the output of the minimum detection signal of the extremum detection unit and the first control input of the third switch, and the second control input of the extremum detection maximum of the second control the third input, connected by the information input to the output of the first key, and the outputs to the summing and subtracting inputs of the first counter, respectively, m output of the second switch and the output of the second counter are respectively frequency-eaten pulse and the code output device. 2. The device according to claim 1, characterized in that the threshold unit contains a reversible counter, AND, OR and NOT elements, and a register connected by input with the threshold code input bus, and output - with a reversible counter installation input, subtracting the input and The installation control input of which the code is the information input and the first control input of the threshold block, respectively, and the bit outputs are connected to the inputs of the OR element connected by the output to the input of the element NOT and to the first input of the AND element, the second input and output of which are a second control input and first output of the threshold unit accordingly, elements avyhod

Description

This is NOT the second output of the nf) poroi.i unit.

3. The device according to claim 1, characterized in that the first switch contains two E elements and two flip-flops, the inputs oonv / ieiiiiH of which are combined and the second control input of the first switch, the first trigger being connected to the first control at the first control The first input of the first switch, the direct output to the first input of the jicpBoro element I, and the inverse B1) 1ho, and the m to the first input of the second terminal I to the counting input of the second trigger, connected directly to the reverse output. with the second inputs of the second n nepiioro elements And, respectively, the third input1) 1 of which are integrated and are the first-input switch of the first switchboard, and the outputs are the first and second inputs of the NS switch;

The invention relates to automation and computer technology and may find application, in particular, in integrators of chromatographic signals.

A device for correcting the baseline is known, which comprises a selector, nj) e voltage generator to frequency, a basic sticky memory unit and an insertion unit 1.

A disadvantage of this device is the reduced accuracy of the baseline correction. This is due to the fact that during the passage of the peak, the device for correcting the baseline is inactive on the nolod1 approximated by a horizontal line. which leads to significant differences in determining the areas of individual peaks due to inaccurate detection of the peak end level due to baseline drift caused by changes in the operating parameters of the chromatograph {) a, asiiatural instability, the presence of irnmes in the carrier gas, electrical causes, and noise and noise.

It is also known a device for baseline correction, integration, which takes into account the baseline liikk drift during the passage of the peak and contains a voltage-frequency converter, three counters, a converter code - voltage, a slope detector, a control unit: and, a memory register, a block code comparison, pulse generator, trigger, two AND elements and OR 2 element.

The device performs a baseline correction during the peak. In this case, the change in the slope of the baseline during the passage of the peak in this device is determined by fixed points describing the behavior of the baseline before determining the beginning of the peak. This is possible with a good separation of the peaks, with close-lying peaks nei being able to record a sufficient number of points to determine the baseline. In addition, baseline drift in cases of chance is of a 1 st character), 1 often leads to the ozovoy line to determine the onset of the onset (P1k. May depend on the baseline behavior (.th line) during the passage of gp-1Ka, which also leads to the basic correction accuracy

.1PPI.

Closest to the proposed device is a correction base. hromatograficheskogo signal containing convert voltage to frequency, the input of which is input m -stpijiicTQa, and the output is connected to the information input m of the first to connected to (output to | -P1format. input to nopoiOBijro b; 1oka, and the first control input is connected to the start of a b.yuka srav: with no codes, connection of input.amp with outputs of the first and second counters, 110. and only two inputs; 1 | m | ne | 5iiOMy and second output first comm vraioiia respectively, the first rule is the input of which is connected with) the house) of the generator, the second control input d .- with the release of Gyrogovogo current. and the Formation input is --- with the output of 1 reenerder; .5ovatel nair cheepy in frequency.

Nel.1: h-ha jOK devices - reduced i. : h01 G.: 1 ..; 1eni of the end of the peak at the same time as the starting point of the baseline drift:; ff / .it to significant Of the m1 in the opreda. sleeps of the square there are notation (bic peaks.

The aim of the invention is to improve the baseline correction point.

The delivered target value is achieved by the fact that the device for the correction of the baseline of the chromatic signal contains, below the voltage-to-frequency converter, the input of which is the input terminal of the device and 1 HOL1. connected to the information input of the first key connected by the output to the information input of the threshold unit, and the 1st) control box of the input unit to the output of the code comparison unit connected by 0 inputs to the outputs of the first and the second from Chichikov, rk) dnkey1SH X with summing inputs to the first and second output of the first commutator, the first

whose control input is connected to. the output of the clock generator, an extremum detection unit, the second and third switches, the second and third keys and the OR element connected by the first input to the first output of the second switch, the second input to the second output of the second switch, the control input of the second key, and the control input reading the second counter and the output to the zeroing inputs of the counters, the first control input of the threshold unit and the second control input of the first switch connected by the information input with the output the key connected by the information input to the output of the voltage to frequency converter, the input of the extremum determination unit and the information input of the second key, the first control input to the output of the clock generator and the second control input of the first key, and the second control input to the output of the code comparison unit and to the second control input of the threshold unit connected by the first and second outputs to the first and second information inputs of the second switch, respectively, the first control input of which connected to the output of the detection signal of the minimum of the extremum detection unit and to the first control input of the third switch, and the second control input to the output of the detection signal of the maximum of the extremum detection unit and to the second control input of the third switch connected by an information input to the output of the first key, and the outputs are with the summing and subtracting inputs of the first counter, respectively, with the output of the second key and the output of the second counter being, respectively, the frequency-pulse and code output mi device.

At the same time, the threshold block contains a reversible counter, elements AND, OR, and NOT and a register connected by an input with a threshold code input, and an output with a reversible counter installation input, the subtracting input and control input of which the code is set are the information input and the first control the input of the threshold unit, respectively, and the bits of the bits are connected to the inputs of the OR element connected by the output to the input of the element NOT and to the first input of the AND element, the second input and output of which are the second control input and the first output each of the threshold block, respectively, and the output of the element is NOT the second output of the threshold block.

In this case, the first switch contains two And elements and two flip-flops, the zeroing inputs of which are combined and are the second control input of the first switch, the first trigger being connected

the counting input to the first control input of the first switch, the direct output to the first input of the first element I, and the inverse output to the first input of the second element I and to the counting input of the second trigger connected to the direct and inverse outputs with the second inputs of the second and first And accordingly, the third inputs of which are combined and are the information input of the first switch, and the outputs are the first and second outputs of the first switch, respectively.

FIG. 1 shows a block diagram of an apparatus for correcting a baseline of a chromatographic signal; in fig. 2 - scheme of the threshold block; in fig. 3 is a diagram of the first switch.

The device for correcting the baseline of the chromatographic signal contains a voltage-to-frequency converter 1, a clock generator 2, an extremum detection unit 3, first, second and third keys 4-6, first and second counters 7 and 8, code comparison units 9, threshold block

10, the first, second and third switches 11-13 and the OR 14 element. Converter 1 is connected to the input of the device and output to the information input of the key 4 connected by the output to the information input of the threshold unit 10, and the first control input - to the output of block 9 comparison codes. The inputs of block 9 are connected to the outputs of the first and second counters 7 and 8, connected by summing inputs to the first and second outputs of the switch I 1, respectively, the first component input of which is connected to the output of the clock generator 2. Element OR 14 is connected by the first input to the first output of the switch 12 , the second input m to the second output of the switch 12, the control input of the key 5 and to the control input of the reading of the counter 8, and the output to the zeroing inputs of the counters 7 and 8, the first control input of the threshold unit 10 and the second control mu switch input

11. The switch 11 is connected by an information input to the output of a key 6 connected by an information input to the output of the converter 1, to the input of the extremum determination unit 3 and to the information input of the key 5, to the first control input to the output of the clock generator 2 and to the second control input of key 4 and the second control input to the output of the code comparison unit 9 and to the second control input of the threshold unit 10. The block 10 is connected by the first and second outputs with the first and second information inputs of the switch 12, respectively, the first control Its input is connected to the minimum detection output of block 3 and to

first upran.chuschsmu isxo.iv 1; n; 1 g;: t ;; ra 13, and the second y || equal; 1Н1О11, and | ) ;. to the maximum detection signal output ;; P. yuka .i and to the second governing board: 1H1O1TsSmu lixoav lamutator 13. Switch 13 is a reference inspin in (|) (:), |; zyoins. the input from Bi) ixo; u) M k.ioch, and the moves with summing; i |); h; g: ak) 1 and the inputs of the counter 7. The output of K.iioia o and 15 |, 1, the course of the counter 8 are correlating a) pulse frequency and code outputs; devices.

The threshold unit 10 can be completely assigned, for example, containing (FIG. 3))) a live counter 15, the elements AND 16, OR 17 and NOT 18 and a register 19 connected to the input bus of the threshold code NO, and Use the input with a regular input of the registrant () of the first 15. 15. Subtracting the input and:; x () d control the installation of the account code NC; -; 15 in; 1 1 1 ин ма ма information from the i-: nejubiM input to the control input b; 1ka 10, respectively, a) the inputs of the digits of the counter D) ID: 110 to the inputs of the element 111 of 18 Sec (m axu / i and: of the element And 6 are the second abutting input of the first and the first 51) first pass; 10 respectively, and the output element. III. 8 second output b, current 10.

The first switchboard I I can b) Py RLLpolpen, for example, content 1m (ft. 4) first and second elements And 20 and 21, and D. triggers 22 and 23. The inputs are off; 22 and 23 are combined and are the second yii ;; aBy switching input; 1a 11. Periphera tripper 22 is connected to the first control input () dc (k) mm gatorg

11, direct output to the n (-P1 "1M input.}

the element And 20. N1pzere1 mm libixtxUiM first input eleme1G | -a And 21 n to cq: -t1; to the entrance of the third tripra 23. Trmps-) 23 connected by the Pr.P51m and pnverS1I-) 1m exit g g; t.1ry. mp entrances of elemento And 20 n 21 respectively -;, - third input | 1 koto1) O (; ee; 1in; m1y and are the information input of the switch I, and the outputs {; dy: 1eGR.; M i-; in4)) bi.,; outputs of the switch 1 I, respectively.

The effect of the ocnoiian device on the principle that when a peak is detected is used

Nj + i - Nj NO. (one)

where N.1 .ti is 11sequences, the values of the signal from; 5 output are converted, 1 1, ..; 1 nPa counters 7 i: 8; and when the end of the nickname Cree;

N, - NI -,. ()

The device works as follows, .- way.

In the initial state 1P1i Kpochi i t): -; ae) you, counters 7 and 8 are cleared i, ;; n B. yuke 10 is set to nopoia No.

The device operates in two modes: in the detection mode of the initial and the detection mode of the end. every;) i;: -; kog () | .; .; ::;; l) is eaten by states of the second 12 liters; its 13 lumps of lators. In both modes, the operation of the device is carried out in three cycles.

Detection mode is the beginning of the peak.

; la111N) 1Y mode is set to stop at the moment of | a |; a, 1 of manually or automatically, and 1 analysis of the analysis - with the signal "Minimum from the output of the block. The second 12 and third 13 switches are in the following states: 1 1х: ip (|) ormatiopny input of switch 12 iod.connected to its first output, and nervous; and the second information inputs of the third room switch 13, respectively, to its nerve and second outputs.

After the input of the converter 1 input voltage to the input voltage frequency, the clock generator 2 is started (the start can be handled or automatic), the first pulse of which is key 1 from the pulse. Through this key and m. Pulses from the output of the converter 1 the voltages in the frequency begin to arrive at (the input input of the switch 11, which during the first clock commutes them but its first output to the summed Huui input of the counter 7.

The operation of the switch 11 is limited to one another.

1.J the initial state of the signal "Start

ana..1i:; a, and in the course of the analysis - a signal with

Element output OR 14, the first 22 and second 23 trigger, which is a counter, are set to the state, elemets And 20 and 2 zaier. With the first pulse with iibixo.bi clock generator 2, the first I (). 1Fr 22 is transferred to a single cocTi.H: iiic. the element And 21 is taken away, the cavijifv (.) 1; the new input of the switch G: .1 () dk.: 11 is to its first output. nmnus With clock out Ti)} j. W. sets the first trigger 22 to:;. ;:;;; ;; state of and the second trigger 23 -; c: iii-nioc, the element And 22 is locked and unlocked E. / i.e. Meterrr 20, i.e. information, lie to the mountains of P, connect it to its second 1;: lho., .. With the third clock pulse, you block. | utago 11 block, because after the mustache, - 15Ki of the first trigger 22 B, the single state element I 20 is locked . The signal from Bbjxo; U e ..: 1 OR OR AND tie removes the blockings. -L s- to (.). M. Of switch 11, sets TpHiTepi) 22 and 23 to the zero state, and the eleiciribi And 20, 21 remain locked .

(1 time; clock clock pulse connects the new information input of switch II to its nerve output. Thus, on {, 1 after the first clock cycle ends, counter 7 is the code corresponding to the current value of the function Nj. Receipt of the second clock pulse from the output of the clock generator 2, impulses from the output of the voltage transformer 1 to the frequency, pass through the key 6. are switched by the switch 11 through its second output to the input of the counter 8, in which at the end of the second clock there is a code corresponding to the current value of Mathematical function Nti-i- The third such1 () clock pulse 2 locks the switch 11 and removes key 4. through which the pulses from the output of the transformed voltage 1 voltage to the frequency begin to flow to the information input of the threshold unit 10 and in parallel through the switch 13 - its first output to the summing input of the counter 7, add its contents (Nj) to the value Ni.i, which is stored in the counter 8 (in the mode of detecting the beginning of the peak Nj4i N {, as the chromatographic function increases). The 5th moment of equalization of the contents of NI + I of counter 8 and count 7 is triggered by block 9, the signal from the output of which locks the first 4 and the second 6 keys, the flow of pulses to the summing input of counter 7 and to the information input of the threshold unit 10 stops. In this case, the key b is a conventional three-input valve, and in the key 4, in addition to the three-input valve, it is necessary to turn on a two-bit double counter, which ensures that the key is unlocked only after the third clock pulse arrives from the generator 2 (for this purpose, you can use the counter, ENTRY INTO cfJCTaB room switch 11).

The number of pulses, entering i.nee into the threshold b.yuk 10 during the third cycle, corresponds to the difference Niti - X {; And N. which, according to a signal from block 9, the passage to the second control input of the threshold bit 10 is compared with the predetermined threshold XQ.

The threshold value is set in register 19 at the beginning of the analysis, and the preparatory signal of unit 10 for operation, the input to input level 1 and the setting of counter code 15, is written to this counter. The subtracting input of the counter 15 receives pulses from the output of the key 4, the number of which is proportional to the difference between the two current values of the function. Resetting the counter 15 to the arrival of the signal from the output of the comparison block 9 corresponds to the fulfillment of the inequality d N5-NO and the appearance of a high potential at the output of the element HE 18, i.e. at the second output of block 10. If in MOMejiT the coincidence of the codes of the counter 7 and 8 in the counter 15 is a non-zero code. which corresponds to the implementation of the inequality, a high potential appears at the output of the element AND 16, i.e. at the first output of block 0.

In the mode of detecting the beginning of a peak, the fulfillment of the inequality L N .No indicates that the beginning of the peak has not yet come. Therefore, the signal from the first information

the input of the switch 12 is transmitted to its first output and through device OR 14 returns device B to its original state, i.e. reset the counters 7 and 8, unlocks the switch 11 and sets the threshold block 10 ready. If condition (1) is fulfilled, then the second output of this com switch, unlock key 5

0 and pulses from the output of converter 1 begin to flow to the frequency-pulse output of the device (to the integral counter, which is not shown). Simultaneously with this signal, through the OR 14 element, the contents of counter 8, which is the signal level value corresponding to the beginning of the peak, is read from the code output of the device to the detection unit redundant plon1 (not shown), the counter 7 is zeroed, and the threshold unit 10 is prepared for

0 work.

Peak end detection mode.

Switching the device to this mode is realized by the signal.m. Of detecting a maximum from the output of block 3.

According to this signal, the information input of the switch 13 is connected to its second output, and the first and second information inputs of the switch 12, respectively, to its second and first output m. The operation of the device in the detection mode of the peak end is similar to the operation of the device in the mode of the beginning of the peak, with the difference that during the third cycle the pulses from the output of the converter 1 of the paired into the frequency are switched through the switch 13 to its second output, and therefore to the subtracting the input of the counter 7, reducing its content (N {) to the value stored in the counter 8 (as in the detection mode of the peak end the chromatographic function decreases).

In the peak end detection mode, the signals from the outputs of the threshold unit 10 change their purpose, since the signal for fulfilling the condition for the peak start detection mode is a non-performing signal

5 conditions for the peak end detection mode, and vice versa, the failure condition signal for the peak start detection mode is a signal to meet the condition for the peak end detection mode. Therefore, as a matter of fact, the first information input of the coaxial switch 12 is connected to its second output, and the second information flow is respectively connected to the first output by the signal "Maximum peak output from unit 3. In the mode of detecting the end of the peak, the mouth of the second the output of the threshold unit 10 passes through the switch 12 to its first output and returns the device to its initial state along

analogy with peak onset detection mode. If the condition is fulfilled, the signal from the second output of the switch 12 locks the key 5, which is a two-way valve with a T-type trigger on the input, which provides the unlocking of the key 5 according to the conditional signal in the mode of beginning of the peak and locking the same signal in peak end detection mode.

At the moment of locking the key 5, the flow of pulses to the integral counter (not shown) stops, the contents of the counter 8, which is the signal value corresponding to the peak end level, is read into the excess area determining unit (not shown), the counter 7 is zeroed, the threshold unit 10 getting ready for work.

Thus, the proposed device allows to increase the accuracy of determining the end of the peak, and therefore, the accuracy of the correction of the baseline of the chromatographic signal. This contributes to a significant reduction in errors in determining such important informative parameters of the peak as its height and area, which, in turn, leads to an increase in the accuracy of determining the percentage of individual components in the analyzed mixture, and this increases the efficiency of chromatographic analysis as a whole.

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Claims (3)

1. DEVICE FOR CORRECTION OF THE BASIC LINE OF THE CHROMATOGRAPHIC SIGNAL, comprising a voltage to frequency converter, the input of which is the input of the device, and the output is connected to the information input of the first key, connected by the output to the information input of the threshold block, and the first control input to the output of the code comparison unit, connected by inputs to the outputs of the first and second counters connected by summing inputs to the first and second outputs of the first switch, respectively, the first control input of which it is single with the output of the clock generator, characterized in that, in order to increase the accuracy of the correction of the baseline, an extremum determination unit, second and third switches, a second and third keys and an OR element connected to the first output of the second switch by the second input - to the second output of the second switch, the control input of the second key and to the input of the read control of the second counter _? and the output - to the inputs of zeroing the counters, the first control input of the threshold block and the second control input of the first switch connected to the information input with the output of the third key, connected by the information input to the output of the voltage to frequency converter, the input of the extrema detection unit and to the information input of the second key , the first control input to the output of the clock generator and to the second control input of the first key, and the second control input to the output of the code comparison unit and to the second a branch input of a threshold block connected by the first and second outputs to the first and second information inputs of the second switch, respectively, the first control input of which is connected to the output of the detection signal of the minimum unit for determining the extrema of X to the first control input of the third ® switch, and the second control input to the output of the detection signal the maximum of the unit for determining the extrema and to the second control input of the third switch connected by the information input to the output of the first key, and the output E - a summing and subtracting input of the first counter, respectively, wherein the second switch output and the second counter are respectively the frequency and pulse code output device. 2. The device according to π. I, characterized in that the threshold block contains a reversible counter, AND, OR, and NOT elements and a register connected to the input of the threshold code input bus, and the output to the installation input of the reverse counter, the subtracting input and the code setting control input of which are an information input and the first control input of the threshold block, respectively, and the outputs of the bits are connected to the inputs of the OR element, connected by the output to the input of the element NOT and the first input of the AND element, the second input and output of which are the second control input and the first output of the threshold block, respectively, and the output of the elements SU, „. 1105914 I I 05914 and HE is the second output of the threshold block. 3. The device according to π. 1, characterized in that the first switch contains two AND elements and two triggers, the zeroing inputs of which are combined and are the second control input of the first switch, the first trigger connecting the counting input to the first control input of the first switch, and the direct output to the first input of the first element And, and an inverse output to the first input of the second element And to the counting input of the second trigger, connected by direct and inverse outputs to the second inputs of the second and first elements And, accordingly, the third inputs which are combined and the information input of the first switch and the outputs are first and second outputs of the first to m of m ut and then p and respectively