CN105181782A - Array type detecting plate for ion mobility spectrometry, detecting system and detecting method - Google Patents

Abstract

The invention discloses an array type detecting plate for an ion mobility spectrometry, a detecting system and a detecting method. Subordinate detecting surfaces are formed in the form of an array; the detecting system comprises an ion mobility tube module, an array type detecting plate module, a trans-impedance amplification module, an analog-to-digital conversion module and a subordinate module, and the signal-to-noise ratio, the sensitivity and the resolution ratio of detecting signals are increased. According to the detecting method, firstly, the subordinate detecting surfaces having equal distance away from a central subordinate detecting surface are divided into one group, obtained mobility time is corrected, average mobility time values of all groups of detecting surfaces are obtained and used as correction coefficients, after mobility time of a to-be-detected substance is corrected with the correction coefficients, components of the substance are determined, and the detecting accuracy can be improved.

Description

A kind of array check-out console for ionic migration spectrometer, detection system and detection method

Technical field

The present invention relates to Ion mobility spectrometry field, particularly relate to a kind of array check-out console for ionic migration spectrometer, detection system and detection method.

Background technology

Ion mobility spectrometry (ionmobilityspectrometry, IMS) be early 1970s occur a kind of new gas phase separation and detection technique.Its core concept distinguishes different materials with the difference of Ion transfer time, adopt the instrument detection sensitivity of Ion mobility spectrometry very high, the material of nanogram level (1ng=10-9kg) or even pieck stage (1pg=10-12kg) can be detected, adopt the instrument of this technology can detect the materials such as chemical warfare agent, drugs, explosive and atmosphere pollution, reconnoitre in airport security, battlefield, environmental monitoring, have important application in commercial production etc.

In ion mobility spectrometry instrument, important parts are transference tube, transference tube to be connected with external electrical field by electrode thus to produce electric field therein, electric field intensity generally selects certain certain value between 150 ~ 1000V/cm as required, as 300V/cm, under electric field action, ion drift is to ion detection plate, thus produces pulse current.In practical application, most ion mobility spectrometry instrument adopts single channel ion check-out console, and if Fig. 1 (a) is ion detection plate front, 71 is check-out console mounting hole, and 72 is check-out console ground connection outer rim, and 73 is ion detection face; Fig. 1 (b) is ion detection back, and 74 is detection faces leading point, and 75 is check-out console outer rim leading point, and ion detection plate front and back is connected by " via hole ".But in practical application, in transference tube, longitudinal electric field and transverse electric field are not uniform electric fields, therefore ion is under electric field action pockety, drift in the Time Inconsistency of ion detection plate, thus cause the pulse current half-peak breadth that detects larger, pulse current amplitude is less, reduces the accuracy of detection of ion mobility spectrometry instrument.

Summary of the invention

In view of this, the invention provides a kind of array check-out console for ionic migration spectrometer, detection system and detection method, sensitivity and the resolution of ion mobility spectrometry instrument can be improved.

For an array check-out console for ion mobility spectrometry instrument, the substrate of this check-out console adopts insulating material to make, and the edge in the front of substrate arranges front signal ground, is provided with array detection faces inside the signal ground of front;

Described array detection faces is made up of with the form of array the square sub-detection faces of N number of mutual insulating; Mutual insulating between sub-detection faces between two; Described N is at least 2;

The edge of the substrate back side of described array check-out console is provided with the reverse side signal ground be electrically connected with front signal ground; Sub-detection faces described in each of front arranges a signal leading point be connected electrically in the equal correspondence of the reverse side of substrate.

Preferably, described substrate adopts teflon to make; Described array detection faces, front signal ground and reverse side signal ground are by formation gold-plated after described substrate surface applies copper.

Preferably, described N gets 64.

Preferably, the electrical connection between front signal ground and reverse side signal ground and between sub-detection faces and corresponding signal leading point is all realized by via hole.

Based on a detection system for array check-out console, comprise across resistance amplification module, analog-to-digital conversion module and accessory module;

The described N road current signal receiving the output of ion mobility spectrometry instrument across resistance amplification module from N number of signal leading point of described array check-out console, is pulse ion electric current, and Bing Jiangge road pulse ion electric current adopts the mode of capacitance integral to be converted to voltage signal;

Analog form from the N road pulse ion electric current received across resistance amplification module is converted to digital form by described analog-to-digital conversion module;

Described accessory module obtains average current after receiving each road pulse ion electric current from described analog-to-digital conversion module; Meanwhile, calculate ion mobility spectrometry instrument intermediate ion and move to after the transit time each sub-detection faces from ion gate, obtain the average mobility time of ion; Concentration and the material composition of the test substance being input to ion mobility spectrometry instrument is determined according to average current and average transit time.

Preferably, the described model across resistance amplification module U1 is AFE0064; Pin 113 to the pin 128 of AFE0064 and pin 1 to pin 48 are the input end of described pulse ion electric current; Pin 105 and 104 is respectively reference voltage input end and negative reference voltage input end, and pin 112 is internal integrator common mode voltage end, by electric capacity C31 decoupling to ground; The differential mode that pin 83 and pin 84 are respectively output channel 0 exports end of oppisite phase and positive terminal; The differential mode that the pin 77 of AFE0064 and pin 78 are respectively output channel 1 exports end of oppisite phase and positive terminal; The pin 98 of AFE0064 is output mode selecting side, connects+3.3V to choose output channel 0 and output channel 1 whether synchronism output; Pin 92 connects+3.3V, with output after making DTD in tri-state; Pin 64 is to the busy indicator signal of accessory module transmission reading; Pin 66 receives the inside filter control signal that accessory module provides; Pin 67 receives the internal integrator reset signal that accessory module provides, to prevent saturation integral; Pin 68 and 69 pin all receives the integrator signal collection and signal reseting controling signal that accessory module provides; Pin 70 receives the clock signal that accessory module provides; The signal that pin 97 receives accessory module to be provided exports with reset input channel counter and enable output channel; Pin 93 ground connection is to select integrator by low level to high level output; Pin 53,55,60,61,75,81,87,100,106,108 pin meets+3.3V, and respectively by electric capacity C8, C10, C12, C3, C14, C15, C16, C17, C18 decoupling to ground; Pin 49,51,52,54,59,62,65,71,73,74,76,79,80,82,85,86,90,91,99,101,102,103,107,109,110 is connected to ground; Pin 56,57,58,63,72,88,89,111 pin is unsettled; The corresponding 8 kinds of integrating capacitors of pin state of pin 94,95,96.

Preferably, the reference voltage of described accessory module is provided by ADR421, the pin 2 of ADR421 is power input, external+5V power supply, and by C32 decoupling to ground, ADR421 pin 4 connects power supply ground, ADR421 pin 6 is output terminal, exports 2.5V, and by electric capacity C33 decoupling to ground, resistance in series R10, R9, R8 are to carry out dividing potential drop simultaneously, to obtain 105 pin and 104 pin that 2.25V and 0.85V is supplied to AFE0064 respectively.

Preferably, analog-to-digital conversion module adopts two panels 14 single channel conversion chip AD9240, is designated as U2 and U3; The connected mode of U2 with U3 is consistent, and the output channel 0 that wherein U2 is AFE0064 provides conversion, and the output channel 1 that U3 is AFE0064 provides conversion; Pin 41 for U2: U2 and pin 42 are the input port of AD9240, are connected the positive differential mode output terminal of AFE0064 output port 0 and anti-phase differential mode output terminal respectively by resistance R1 with resistance R2; The pin 32 of U2 is reference voltage end, and by electric capacity C3 and C4 decoupling to ground; The pin 31 of U2 and pin 33 short circuit ground connection are to select internal reference voltage 2.5V and to ensure zero-bias voltage; The decoupling network that the pin 36,37,39 of U2 is consisted of electric capacity C5, C6, C7, C9 carries out decoupling; The pin 35 of U2 passes through resistance R3 ground connection to select the sample frequency of AD9240; Pin 4 and the pin 28 of U2 are power input, external+5V power supply, and by electric capacity C1 and C2 decoupling to ground; The pin 2 of U2 and pin 29, for hold in analog, connect power supply ground; Pin 3 and pin 6 are digital power input end, external+5V power supply, and by electric capacity C20 and C21 decoupling to ground; Pin 1 and pin 5, for digitally to hold, connect digitally; The pin 7 of U2 receives the clock signal that accessory module provides; The pin 11 of U2,12,13,14,15,16,17,18,19,20,21,22,23,24 be parallel output mouth, receive the digital signal after the conversion of accessory module transmission respectively; The pin 25 of U2 provides spilling indicator signal to accessory module; Pin 8,9,10,26,27,30,34,38,40,43,44 unsettled; Power supply ground be digitally connected by resistance R4.

A kind of material concentration detection method based on array check-out console, N number of signal leading point received pulse gas current from described array check-out console is averaging, draw total pulse current mean value, in order to detect the concentration being input to the test substance of ion mobility spectrometry instrument.

Based on a material composition detection method for array check-out console, concrete steps are as follows:

Step 1, open ion mobility spectrometry instrument, pass into standardizing chemical reagent, close ion gate, standard reagent in the ionization of ionization district, for each sub-detection faces arranges a timer; Open ion gate, start each timer simultaneously, when ion arrives sub-detection faces, stop corresponding timer, obtain the transit time of ion in each sub-detection faces; The described ion gate opening time controls between 100us ~ 500us.

Step 2, those identical with array check-out console centre distance for center sub-detection faces are divided into one group, the Ion transfer time corresponding to all sub-detection faces in every group averages, and obtains the Ion transfer time average of this group;

Step 3, with Ion transfer time average t corresponding to one group sub-detection faces nearest apart from sub-detection faces center _afor time reference, respectively divided by the Ion transfer time average that other is respectively organized, obtain the correction factor P of the transit time of each group _x;

$P_X=\frac{t_A}{t_X};$

Wherein t _xrepresent except other of one group of nearest sub-detection faces organizes sub-detection faces;

Step 4, repetition step 1, to 3, obtain correction time Coefficient Mean after multiple averaging ;

Step 5, pass into chemical reagent M to be detected, record the transit time that each sub-detection faces detects, and calculate the Ion transfer time average of each group of sub-detection faces according to the method for step 2, be multiplied by correction time Coefficient Mean respectively obtain the Ion transfer time normalization value of each group;

Step 6, the Ion transfer time normalization value of each group to be averaging, to obtain the average mobility time of ion, determine the material composition of chemical reagent M to be detected accordingly.

The present invention has following beneficial effect:

(1) single formula ion detection plate is improved to array check-out console by the present invention, and devises coherent signal treatment circuit, derives backoff algorithm, improves the signal to noise ratio (S/N ratio) of detection signal, sensitivity and resolution.

(2) first sub-for distance center detection faces is divided into one group apart from identical sub-detection faces by detection method of the present invention, carry out obtaining transit time correction, obtain the transit time mean value of each group of detection faces, as correction factor, with this correction factor to after the transit time correction of test substance, determine the composition of material again, the accuracy of detection can be improved.

Accompanying drawing explanation

Fig. 1 is existing single formula ion detection plate schematic diagram;

Fig. 2 is existing ion migration tube structure schematic diagram;

Fig. 3 (a) is transference tube electric field intensity inside high distribution schematic diagram;

Fig. 3 (b) is for detecting pulse current intensity schematic diagram in transference tube;

Fig. 4 (a) is hyperchannel ion detection plate Facad structure schematic diagram of the present invention;

Fig. 4 (b) is hyperchannel ion detection plate inverse layer structure schematic diagram of the present invention;

Fig. 5 is across resistance amplification module and analog-to-digital conversion module circuit connection diagram;

Fig. 6 is accessory module structural representation.

Wherein, 1-drying agent, 2-air pump, 3-electrode slice, 4-radioactive source, 5-ion gate, 6-grid screen, 60-moves ion, 7-ion detection plate, 8-venthole, 9-pulse current extension line, 71-mounting hole, 72-front signal ground, 73-array detection faces, 74-signal leading point, 75-reverse side signal ground leading point, 76-reverse side signal ground.

Embodiment

To develop simultaneously embodiment below in conjunction with accompanying drawing, describe the present invention.

As shown in Figure 2,1 is drying agent to Ion transfer module in ion mobility spectrometry instrument, and 2 is air pump, and 3 is electrode, and 4 is Ni63 radioactive source, and 5 is ion gate, and 6 is grid screen, and 7 is ion detection plate, and 8 is gas outlet, and 9 is pulse current extension line.From ion mobility spectrometry relevant knowledge, when the external voltage in certain gradient increasing or decreasing of electrode slice 3, electric field is formed in transference tube, chemical substance to be detected in ionization district first by ray ionization that Ni63 radioactive source 4 is launched, form charged ion, control the periodic switching pulses of ion gate 5, when ion gate 5 is opened, charged ion produces drift under electric field action, and pulse current detected on ion detection plate 7.When electric field lower (E < 1000V/cm), the average mobility speed v of ion and electric field strength E meet following relation:

v＝K×E(1)

In formula, K is ion mobility (definition of mobility refers to the migration velocity of ion under unit electric field effect), relevant with the molecular property of gas in this ion and transference tube.When migration intraductal pressure and temperature one timing, K value is certain value.

Formula (1) shows that Ion transfer speed depends on transference tube internal electric field.And transference tube internal electric field is as shown in accompanying drawing 3 (a), ordinate E represents electric field intensity, and horizontal ordinate x represents the distance in electric field intensity test point and migration tube axle center.Ideally, the field strength distribution in transference tube is as a curve in Fig. 3 (a), and namely electric field intensity is a fixed value; But, because the increase of electric field intensity along with distance can decay, the actual field strength distribution of transference tube inside is as the b curve in Fig. 3 (a), be a die-away curve, namely in migration tube, cardioelectric field is comparatively strong, and more weak near the electric field of migration tube inwall, size distribution like this due to electric field intensity is inconsistent, cause identical ion in transition process, in transference tube, the Ion transfer of core is very fast, and slower near the Ion transfer speed of Ion transfer inside pipe wall.Thus make identical ion arrive the Time Inconsistency of ion detection plate 7, add the pulse current half-peak breadth that ion detection plate 7 detects, shown in figure as right in Fig. 3 (b), a is the ideally pulse current that detects of ion detection plate, and b is the pulse current detected under actual conditions.

As shown in Figure 4, array detection faces 73 is made up of with the form of array the square sub-detection faces of multiple mutual insulating array ion detection plate of the present invention, between two mutual insulating between sub-detection faces.The background material of array ion detection plate is the Teflon of high insulating coefficient, Fig. 4 (a) is check-out console front, wherein 71 is mounting hole, it is gold-plated that mounting hole inwall applies copper, reduce equivalent resistance to be well connected with the back side to make ion detection plate front, 72 is ion detection plate earthing frame, gold-plated to reduce equivalent resistance after applying copper, improve signal quality, 73 is array detection faces, gold-plated after applying copper, 8 row 8 row are uniformly distributed totally 64,64 sub-detection faces are in the same size, long and are widely 3mm, and sub-detection faces spacing is 1mm; Fig. 4 (b) is ion detection back, and wherein 74 is pulsed current signal leading point, totally 64 tunnels, and 75 is reverse side signal ground leading point.64 sub-detection faces 73 are connected respectively by " via hole " with 64 pulsed current signal leading points 74, and via diameter is 0.2mm.

Adopt the AFE0064 being exclusively used in the detection of medical x-ray flat board across resistance amplification module, its reference voltage is provided by reference voltage chip ADR421.5 be described as follows by reference to the accompanying drawings: the pin 113 of AFE0064,114 ..., 128 and pin 1,2 ..., 48 be 64 road input ends, connect respectively ion detection plate 64 road current signal i1, i2 ..., i64; The pin 105 and 104 of AFE0064 is respectively reference voltage input end and negative reference voltage input end, reference voltage is provided by ADR421, the pin 2 of ADR421 is power input, external+5V power supply, and by C32 decoupling to ground, ADR421 pin 4 connects power supply ground, ADR421 pin 6 is output terminal, exports 2.5V, and by electric capacity C33 decoupling to ground, resistance in series R10, R9, R8 are to carry out dividing potential drop simultaneously, to obtain 105 pin and 104 pin that 2.25V and 0.85V is supplied to AFE0064 respectively; The pin 112 of AFE0064 is internal integrator common mode voltage end, by electric capacity C31 decoupling to ground; The differential mode that the pin 83 of AFE0064 and pin 84 are respectively output channel 0 exports end of oppisite phase and positive terminal; The differential mode that the pin 77 of AFE0064 and pin 78 are respectively output channel 1 exports end of oppisite phase and positive terminal; The pin 98 of AFE0064 is output mode selecting side, connects+3.3V and exports (synchronously referring to that the output channel 0 of AFE0064 and output channel 1 export here) to choose " synchronously " simultaneously; The pin 92 of AFE0064 connects+3.3V, with output after making DTD in tri-state; The pin 64 of AFE0064 is output signal pin, connects FPGA and transmits the busy indicator signal of reading to FPGA; The pin 66 of AFE0064 connects FPGA and provides inner filter control signal by FPGA; The pin 67 of AFE0064 connects FPGA and provides internal integrator reset signal by FPGA, to prevent saturation integral; The pin 68 of AFE0064 is all connected FPGA with 69 pin and provides integrator signal collection and signal reseting controling signal respectively by FPGA; Pin 70 connects FPGA and provides clock signal by DPGA; Pin 97 connects FPGA and provides signal to export with reset input channel counter and enable output channel by FPGA; Pin 93 ground connection is to select integrator by low level to high level output; Pin 53,55,60,61,75,81,87,100,106,108 pin meets+3.3V, and respectively by electric capacity C8, C10, C12, C3, C14, C15, C16, C17, C18 decoupling to ground; Pin 49,51,52,54,59,62,65,71,73,74,76,79,80,82,85,86,90,91,99,101,102,103,107,109,110 is connected to ground; Pin 56,57,58,63,72,88,89,111 pin is unsettled; AFE0064 can select 8 kinds of integrating capacitors, corresponding 8 kinds of quantity of electric charge range of receiving, respectively by the pin Determines of pin 94,95,96, and the equal ground connection of 94,95,96 pin herein.The voltage U n of the correspondence n-th road check-out console of the output of AFE0064 can be tried to achieve by following formula, and C represents integrating capacitor, and in represents the pulse current that the n-th road check-out console receives, and Qr represents electric charge quantities received, and Upm represents the difference of reference voltage and negative reference voltage

$U_n=\frac{1}{C}\&Integral;i_n\&CenterDot;dt---\left(2\right)$

$C=\frac{Q_r}{U_{pm}}---\left(3\right)$

Analog-to-digital conversion module adopts two panels 14 single channel conversion chip AD9240, as U2 and U3 in accompanying drawing 5.5 be described as follows that (connected mode of U2 with U3 is consistent by reference to the accompanying drawings, the output channel 0 being AFE0064 unlike U2 provides conversion, the output channel 1 that U3 is AFE0064 provides conversion, here for U2): the pin 41 and 42 of U2 is the input port of AD9240, is connected the positive differential mode output terminal of AFE0064 output port 0 and anti-phase differential mode output terminal respectively by R1 with R2; The pin 32 of U2 is reference voltage end, and by electric capacity C3 and C4 decoupling to ground; The pin 31 of U2 and pin 33 short circuit ground connection are to select internal reference voltage 2.5V and to ensure zero-bias voltage; The decoupling network that the pin 36,37,39 of U2 is consisted of electric capacity C5, C6, C7, C9 carries out decoupling; The pin 35 of U2 passes through resistance R3 ground connection to select the sample frequency of AD9240; Pin 4 and the pin 28 of U2 are power input, external+5V power supply, and by electric capacity C1 and C2 decoupling to ground; The pin 2 of U2 and pin 29, for hold in analog, connect power supply ground; Pin 3 and pin 6 are digital power input end, external+5V power supply, and by electric capacity C20 and C21 decoupling to ground; Pin 1 and pin 5, for digitally to hold, connect digitally; The pin 7 of U2 connects FPGA and provides clock signal by FPGA; The pin 11 of U2,12,13,14,15,16,17,18,19,20,21,22,23,24 be parallel output mouth, connect FPGA respectively and to the digital signal after FPGA transmission conversion; The pin 25 of U2 connects FPGA and provides spilling indicator signal to FPGA; Pin 8,9,10,26,27,30,34,38,40,43,44 unsettled; Power supply ground be digitally connected by resistance R4.

Accessory module comprises power module, level switch module, field programmable gate array (FPGA), sound and light alarm etc., as shown in Figure 6.Power module provides+5V, + 3.3V, + 2.5V, + 1.2V, level switch module is used for the+3.3V signal of+5V of AD9240 signal and FPGA to switch, FPGA provides the STI of AFE0064, CLK, SHR, SHS, IRST, INTG signal, and receive the eoc signal of AFE0064 transmission, the CLKA of two panels AD9240 is provided, CLKB signal, and receive the OA of two panels AD9240, A-B1, A-B2, A-B3, A-B4, A-B5, A-B6, A-B7, A-B8, A-B9, A-B10, A-B11, A-B12, A-B13, A-B14 and OB, B-B1, B-B2, B-B3, B-B4, B-B5, B-B6, B-B7, B-B8, B-B9, B-B10, B-B11, B-B12, B-B13, B-B14, sound and light alarm refer to chemical substance concentration to be detected exceed standard or operation irregularity time send sound and light alarm.

Provide the correction algorithm improving ion detection plate accuracy of detection below:

The first step: transit time correction

1, ion mobility spectrometry instrument is opened, pass into standardizing chemical reagent, close ion gate, standard reagent opens ion gate after the ionization of ionization district, and the opening time is approximately 300us, start timing simultaneously, ion through migrating to ion detection plate after a while in drift region, stops timing, obtains transit time tn after the n-th ion detection face, tunnel detects pulse current, due to the being distributed symmetrically property in ion detection face, have in theory:

t ₂₈＝t ₂₉＝t ₃₇＝t ₃₆(4)；

t ₂₀＝t ₂₁＝t ₃₀＝t ₃₈＝t ₄₅＝t ₄₄＝t ₃₅＝t ₂₇(5)；

t ₁₉＝t ₂₂＝t ₄₆＝t ₄₃(6)；

t ₁₂＝t ₁₃＝t ₃₁＝t ₃₉＝t ₅₂＝t ₅₃＝t ₃₄＝t ₂₆(7)；

t ₁₁＝t ₁₄＝t ₂₃＝t ₄₇＝t ₅₄＝t ₅₁＝t ₄₂＝t ₁₈(8)；

t ₁₀＝t ₁₅＝t ₅₅＝t ₅₀(9)；

t ₄＝t ₅＝t ₃₂＝t ₄₀＝t ₆₁＝t ₆₀＝t ₃₃＝t ₂₅(10)；

t ₃＝t ₆＝t ₂₄＝t ₄₈＝t ₆₂＝t ₅₉＝t ₄₁＝t ₁₇(11)；

t ₂＝t ₇＝t ₁₆＝t ₅₆＝t ₆₃＝t ₅₈＝t ₄₉＝t ₉(12)；

t ₁＝t ₈＝t ₆₄＝t ₅₇(13)；

2,64 way detection faces can be divided into 10 groups according to formula (4) to formula (13), be respectively A, B, C, D, E, F, G, H, I, J group, every group is averaged:

$t_A=\frac{t_{28}+t_{29}+t_{37}+t_{36}}{4}---\left(14\right);$

$t_B=\frac{t_{20}+t_{21}+t_{30}+t_{38}+t_{45}+t_{44}+t_{35}+t_{27}}{8}---\left(15\right);$

$t_C=\frac{t_{19}+t_{22}+t_{46}+t_{43}}{4}---\left(16\right);$

$t_D=\frac{t_{12}+t_{13}+t_{31}+t_{39}+t_{52}+t_{53}+t_{34}+t_{26}}{8}---\left(17\right);$

$t_E=\frac{t_{11}+t_{14}+t_{23}+t_{47}+t_{54}+t_{51}+t_{42}+t_{18}}{8}---\left(18\right);$

$t_F=\frac{t_{10}+t_{15}+t_{55}+t_{50}}{4}---\left(19\right);$

$t_G=\frac{t_4+t_5+t_{32}+t_{40}+t_{61}+t_{60}+t_{33}+t_{25}}{8}---\left(20\right);$

$t_H=\frac{t_3+t_6+t_{24}+t_{48}+t_{62}+t_{59}+t_{41}+t_{17}}{8}---\left(21\right);$

$t_I=\frac{t_2+t_7+t_{16}+t_{56}+t_{63}+t_{58}+t_{49}+t_9}{8}---\left(22\right);$

$t_J=\frac{t_1+t_8+t_{64}+t_{57}}{4}---\left(23\right);$

3, after obtaining 10 groups of transit times, with t _afor time reference, define the correction factor of 10 groups of transit times: $P_X=\frac{t_A}{t_X}---\left(24\right)$

Wherein, X=(A, B ..., J).

4, repeat above-mentioned steps, after multiple averaging, obtain correction time FACTOR P _x;

5, pass into chemical reagent M to be detected, record the transit time that 64 ion detection faces, tunnel detect, and obtain the mean value of 10 groups of transit times according to formula (14) to formula (23), suppose that the mean value of Group X transit time is then have after Ion transfer time normalization:

$t_X^{M^{\&prime;}}={\stackrel{\&OverBar;}{P}}_X\&CenterDot;t_X^M---\left(25\right)$

6, calculate the average mobility time of ion, computing formula is as follows:

$t^M=\frac{\underset{K=A}{\overset{J}{\&Sigma;}}{t}_K^{M^{\&prime;}}}{10}---\left(26\right)$

Second step: pulse current size correction

1, FPGA reads the voltage signal Un after current/voltage-converted and analog to digital conversion, and carries out differential process to formula (2), can obtain the size of current that ion detection plate detects to be

$i_n=C\frac{{\mathrm{dU}}_n}{dt}---\left(27\right)$

2, repeatedly pass into chemical substance to be detected and obtain the current average of each passage according to formula (27), obtain the size of current of 64 passages respectively, then arithmetic mean obtains total pulse current mean value, and computing formula is as follows: $i=\frac{\underset{k=1}{\overset{64}{\&Sigma;}}{i}_k}{64}---\left(28\right)$

3rd step: try to achieve revised transit time and pulse current size according to formula (26) and formula (28), and material composition and roughly concentration that chemical substance to be detected can be determined according to this.

In sum, these are only preferred embodiment of the present invention, be not intended to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (10)

1. the array check-out console for ion mobility spectrometry instrument, it is characterized in that, the substrate of this check-out console adopts insulating material to make, the edge in the front of substrate arranges front signal ground (72), and front signal ground (72) inner side is provided with array detection faces (73);

Described array detection faces (73) is made up of with the form of array the square sub-detection faces of N number of mutual insulating; Mutual insulating between sub-detection faces between two; Described N is at least 2;

The edge of the substrate back side of described array check-out console is provided with the reverse side signal ground (76) be electrically connected with front signal ground (72); Sub-detection faces described in each of front arranges a signal leading point (74) be connected electrically in the equal correspondence of the reverse side of substrate.

2. a kind of array check-out console for ion mobility spectrometry instrument as claimed in claim 1, is characterized in that, described substrate adopts teflon to make; Described array detection faces (73), front signal ground (72) and reverse side signal ground (76) are by formation gold-plated after described substrate surface applies copper.

3. a kind of array check-out console for ion mobility spectrometry instrument as claimed in claim 1, it is characterized in that, described N gets 64.

4. a kind of array check-out console for ion mobility spectrometry instrument as claimed in claim 1, it is characterized in that, the electrical connection between front signal ground (72) and reverse side signal ground (76) and between sub-detection faces and corresponding signal leading point (74) is all realized by via hole.

5. based on a detection system for array check-out console according to claim 1, it is characterized in that, comprise across resistance amplification module, analog-to-digital conversion module and accessory module;

The described N road current signal receiving the output of ion mobility spectrometry instrument across resistance amplification module from N number of signal leading point (74) of described array check-out console, be pulse ion electric current, Bing Jiangge road pulse ion electric current adopts the mode of capacitance integral to be converted to voltage signal;

Analog form from the N road pulse ion electric current received across resistance amplification module is converted to digital form by described analog-to-digital conversion module;

Described accessory module obtains average current after receiving each road pulse ion electric current from described analog-to-digital conversion module; Meanwhile, calculate ion mobility spectrometry instrument intermediate ion and move to after the transit time each sub-detection faces from ion gate, obtain the average mobility time of ion; Concentration and the material composition of the test substance being input to ion mobility spectrometry instrument is determined according to average current and average transit time.

6. detection system as claimed in claim 5, is characterized in that, the described model across resistance amplification module U1 is AFE0064; Pin 113 to the pin 128 of AFE0064 and pin 1 to pin 48 are the input end of described pulse ion electric current; Pin 105 and 104 is respectively reference voltage input end and negative reference voltage input end, and pin 112 is internal integrator common mode voltage end, by electric capacity C31 decoupling to ground; The differential mode that pin 83 and pin 84 are respectively output channel 0 exports end of oppisite phase and positive terminal; The differential mode that the pin 77 of AFE0064 and pin 78 are respectively output channel 1 exports end of oppisite phase and positive terminal; The pin 98 of AFE0064 is output mode selecting side, connects+3.3V to choose output channel 0 and output channel 1 whether synchronism output; Pin 92 connects+3.3V, with output after making DTD in tri-state; Pin 64 is to the busy indicator signal of accessory module transmission reading; Pin 66 receives the inside filter control signal that accessory module provides; Pin 67 receives the internal integrator reset signal that accessory module provides, to prevent saturation integral; Pin 68 and 69 pin all receives the integrator signal collection and signal reseting controling signal that accessory module provides; Pin 70 receives the clock signal that accessory module provides; The signal that pin 97 receives accessory module to be provided exports with reset input channel counter and enable output channel; Pin 93 ground connection is to select integrator by low level to high level output; Pin 53,55,60,61,75,81,87,100,106,108 pin meets+3.3V, and respectively by electric capacity C8, C10, C12, C3, C14, C15, C16, C17, C18 decoupling to ground; Pin 49,51,52,54,59,62,65,71,73,74,76,79,80,82,85,86,90,91,99,101,102,103,107,109,110 is connected to ground; Pin 56,57,58,63,72,88,89,111 pin is unsettled; The corresponding 8 kinds of integrating capacitors of pin state of pin 94,95,96.

7. detection system as claimed in claim 6, it is characterized in that, the reference voltage of described accessory module is provided by ADR421, and the pin 2 of ADR421 is power input, external+5V power supply, and by C32 decoupling to ground, ADR421 pin 4 connects power supply ground, and ADR421 pin 6 is output terminal, export 2.5V, and by electric capacity C33 decoupling to ground, resistance in series R10, R9, R8 are to carry out dividing potential drop, to obtain 105 pin and 104 pin that 2.25V and 0.85V is supplied to AFE0064 respectively simultaneously.

8. detection system as claimed in claims 6 or 7, is characterized in that, analog-to-digital conversion module adopts two panels 14 single channel conversion chip AD9240, is designated as U2 and U3; The connected mode of U2 with U3 is consistent, and the output channel 0 that wherein U2 is AFE0064 provides conversion, and the output channel 1 that U3 is AFE0064 provides conversion; Pin 41 for U2: U2 and pin 42 are the input port of AD9240, are connected the positive differential mode output terminal of AFE0064 output port 0 and anti-phase differential mode output terminal respectively by resistance R1 with resistance R2; The pin 32 of U2 is reference voltage end, and by electric capacity C3 and C4 decoupling to ground; The pin 31 of U2 and pin 33 short circuit ground connection are to select internal reference voltage 2.5V and to ensure zero-bias voltage; The decoupling network that the pin 36,37,39 of U2 is consisted of electric capacity C5, C6, C7, C9 carries out decoupling; The pin 35 of U2 passes through resistance R3 ground connection to select the sample frequency of AD9240; Pin 4 and the pin 28 of U2 are power input, external+5V power supply, and by electric capacity C1 and C2 decoupling to ground; The pin 2 of U2 and pin 29, for hold in analog, connect power supply ground; Pin 3 and pin 6 are digital power input end, external+5V power supply, and by electric capacity C20 and C21 decoupling to ground; Pin 1 and pin 5, for digitally to hold, connect digitally; The pin 7 of U2 receives the clock signal that accessory module provides; The pin 11 of U2,12,13,14,15,16,17,18,19,20,21,22,23,24 be parallel output mouth, receive the digital signal after the conversion of accessory module transmission respectively; The pin 25 of U2 provides spilling indicator signal to accessory module; Pin 8,9,10,26,27,30,34,38,40,43,44 unsettled; Power supply ground be digitally connected by resistance R4.

9. the material concentration detection method based on the array check-out console in claim 1 to 6 described in any one, it is characterized in that, N number of signal leading point (74) received pulse gas current from described array check-out console is averaging, draw total pulse current mean value, in order to detect the concentration being input to the test substance of ion mobility spectrometry instrument.

10., based on a material composition detection method for the array check-out console of claim 1, it is characterized in that, concrete steps are as follows:

Step 1, open ion mobility spectrometry instrument, pass into standardizing chemical reagent, close ion gate (5), standard reagent in the ionization of ionization district, for each sub-detection faces arranges a timer; Open ion gate (5), start each timer simultaneously, when ion arrives sub-detection faces, stop corresponding timer, obtain the transit time of ion in each sub-detection faces; Described ion gate (4) opening time controls between 100us ~ 500us;

Step 2, those identical with array check-out console centre distance for center sub-detection faces are divided into one group, the Ion transfer time corresponding to all sub-detection faces in every group averages, and obtains the Ion transfer time average of this group;

Step 3, with Ion transfer time average t corresponding to one group sub-detection faces nearest apart from sub-detection faces center _afor time reference, respectively divided by the Ion transfer time average that other is respectively organized, obtain the correction factor P of the transit time of each group _x;

$P_X=\frac{t_A}{t_X};$

Wherein t _xrepresent except other of one group of nearest sub-detection faces organizes sub-detection faces;

Step 4, repetition step 1, to 3, obtain correction time Coefficient Mean after multiple averaging

Step 5, pass into chemical reagent M to be detected, record the transit time that each sub-detection faces detects, and calculate the Ion transfer time average of each group of sub-detection faces according to the method for step 2, be multiplied by correction time Coefficient Mean respectively obtain the Ion transfer time normalization value of each group;

Step 6, the Ion transfer time normalization value of each group to be averaging, to obtain the average mobility time of ion, determine the material composition of chemical reagent M to be detected accordingly.