Source of ionisation based on barrier discharge
 Method of separating ions of organic and bioorganic compounds based on ion mobility increment and transportation of said ions inside supersonic gas stream / 2468464Basis of the invention is separating ions from an external source in an ion mobility increment spectrometer (IMIS) with a cylindrical symmetrical shape with a partitioned external electrode, where independently varying dispersion voltage and compensating voltage is applied across sections. These voltages facilitate focusing of the desired ions in the initial section of the drift channel near the middle of the analytical interval of the IMIS, their controlled shift to the outer surface of the external electrode in the middle part of the drift channel and controlled shift to the central electrode in the final part of the drift channel. This enables to primarily transmit desired ions with offset from impurity ions due to their probable dying at electrodes of the IMIS. Surviving ions, under the action of the electric field and a small portion of the gas stream entering the capillary which forms a supersonic gas stream, drift into that capillary and inside the supersonic gas stream coming out of that capillary and enter into the next mass analyser. Separation of signals from all ions focused inside the IMIS is possible based on detecting two-dimensional or four-dimensional distribution of flux density of the detected ions when scanning voltages which shift ions to electrodes of the IMIS. |
 Electrode system of linear ion trap / 2466475Electrode system of a linear ion trap has four electrodes, each pair oppositely located. Plains of symmetry of electrode pairs are perpendicular to each other. The system differs from prototype in that each electrode of at least one pair has in the cross section substantially the shape of an isosceles triangle. The vertex of the triangle is directed towards the longitudinal axis of the trap. The best result is achieved when angle between lateral sides of the triangle is 130°-152°, i.e, the angle between the working surfaces of the electrodes is 130°-152°. The width of the longitudinal slit for ejecting ions in such an electrode is less than 24% of the inscribed radius of the trap. The disclosed electrode system for a linear ion trap enables to achieve high resolution which is comparable with the resolution of ion traps of hyperbolic electrode section, i.e. significantly higher than can be achieved by the prototype ion trap. At the same time the working surface of electrodes in proposed system is composed of flat surfaces, which are placed at an angle whose vertex is directed towards the axis of the ion trap. Manufacturing of such electrodes is much simpler. An angle in the region of the slit of the electrode compensates for local weakening of the field. |
 Apparatus for manipulating charged particles / 2465679Apparatus for manipulating charged particles has a set of electrodes arranged to form a channel for movement of charged particles, as well as an electric power supply which applies supply voltage across the electrodes, which enables to form a non-uniform high-frequency electric field in the channel, the pseudopotential of which has one or more local extrema along the length of the channel for movement of charged particles on at least a certain time interval, wherein at least one of said pseudopotential extrema moves in time on at least a certain time interval on at least part of the channel for movement of charged particles. |
 Method of determining isotopic composition of methane / 2461909Method involves feeding a sample for analysis; converting methane to an analyte in air or oxygen-containing gas; feeding the analyte for analysis; ionising the analyte; isotopic analysis of ions of the analyte using a mass-analyser. The analyte is methanol and conversion is carried out via gaseous electrical discharge. |
 Method of analysing charged particles based on energy mass and apparatus for realising said method / 2459310Analysis based on energy and mass is carried out in superimposed radial electric field of a Hughes-Rozhansky energy analyser and the magnetic field if a Wien filter and the longitudinal electric field of the Wien filter which lies across said two fields. The Hughes-Rozhansky energy analyser and the Wien filter are merged in a single structure, the Wien filter being cylindrical. The ion detector and the distance between cylindrical plates are determined by focusing conditions of the target ions. |
 Analyser for flight-type quadrupole mass-spectrometer with three-dimensional focusing / 2458428Analyser has an electrode system and two electrodes which bound the electrode system on the z axis, with two holes in one of said electrodes for inlet and outlet of analysed ions. Coordinate values of the centres of the holes for inlet and outlet of ions on similar coordinate axes are equal in magnitude, but at least one pair of corresponding coordinate values has different signs. |
 Multi-reflecting time-of-flight mass-analyser and time-of-flight mass-spectrometer having said mass-analyser / 2458427Multi-reflecting time-of-flight mass-analyser has two parallel gridless ion mirrors, each having an elongated structure in the direction (Z) of drift. These ion mirrors provide a convoluted ion path formed by multiple reflections of ions in the direction (X) of flight, orthogonal to the direction (Z) of drift. The analyser also has an additional gridless ion mirror for reflecting ions in the direction (Z) of drift. During operation, ions are spatially separated according to the mass-to-charge ratio due to different time of flight along the convoluted ion path and ions having essentially the same mass-to-charge ratio are subject to energy focusing with respect to the direction of flight and drift. |
 Static ion mass analyser / 2456700Static ion mass analyser comprises a source of ions, a focusing system, an object slot, an aperture diaphragm, energy-dispersed electrostatic sector and magnet sector. The electrostatic sector is installed relative to the magnetic sector so that directions of optical axes rotation in the electrostatic sector and the magnetic sector match each other. The electrostatic sector is installed relative to the source of ions so that the plane of the optical image of the object slot is located between the electrostatic sector and the magnetic sector. In the plane of the optical image of the object slot there is an energy-filtering diaphragm. There is a collimating lens installed between the electrostatic sector and the magnetic sector. |
 Ion mobility spectrometer / 2455725Ion mobility spectrometer has a reaction chamber (1), a drift electrode (2) and an ion detector (3). The reaction chamber (1) is fitted with an input port (4) for feeding the analysed substance in a mixture with a carrier gas and a corona discharge source made in form of segment of a hemisphere (5) on whose inner surface facing the drift electrode (2) there are metal spikes (6) with small curvature radius at the apex of the spikes. A controlled grid valve (7) is placed between the ion source and the drift electrode (2). The drift electrode (2) is made from high-resistivity material with resistivity in the range of (0.3-2.0)×104 ohm×m, and is connected to a drift voltage (8) source. An ion detector (3) is placed at the output of the drift electrode (2). |
 Apparatus for orthogonal input of ions into ion-drift or mass-spectrometer / 2451364Apparatus for separation and orthogonal input of ions is in form of a T-shaped coupling of a gas-dynamic and an input channel, wherein the input channel consists of a diaphragm and an electrostatic lens system. The electrostatic field of the lens system of the orthogonal channel draws ions into the drift region and big droplets fly in the initial direction. |
 Methods and device for controlling installation incorporating quadruple ion trap / 2249275Digital excitation device for quadruple installation such as quadruple ion trap 20, 21 has digital signal generator 11, 13, 14, and switching equipment 16, 17 that functions to alternately change over voltages 18, 19 from higher to lower level (V1, V2) and vice versa for shaping voltage in the form of square wave. Dipole excitation voltage is also supplied to quadruple installation for exciting resonant vibration motions of ions. |
 Method for analyzing charged particles in hyperboloid mass spectrometer of three-dimensional ion trap type / 2260871Proposed method for analyzing charged particles in hyperboloid mass spectrometry of three-dimensional ion trap type includes measurement of electric field parameters (mass spectrum sweep) started simultaneously with input of ions in trap space and completion of ion input as soon as working point of ion corresponding to one of boundaries of mass operating range reaches boundary of stability zone whose use discharges ions from trap. |
 Method for serviceability check of ion-mobility spectrometer incorporating surface-ionized ion thermoemitter / 2263996Proposed method for serviceability check of ion-mobility spectrometer incorporating surface-ionized ion thermoemitter, including spectrometer checkup dispensing with reference materials and for measuring spectrometer parameters in single cycle includes air pumping through spectrometer at volume velocity ranging between 2 and 10 l/min, application of dc voltage Uacc between thermoemitter plus and ion lens electrode minus, measurement of thermoemitter ion current Ite by means of external device, and setting of thermoemitter operating temperature Top between 250 and 650 °C and Uacc between 30 and 600 V so as to provide for thermoemitter ion current Ite of (10-11 - 10-8) A; recording of ion drift spectrum; evaluation of half-width of ion current peak in drift spectrum at half its height ΔU, ion current peak maximum Imax, and compensating voltage Uc in ion current peak maximum; calculation of Kpc =(Imax/ Ite), and estimation of condition of ion mobility spectrometer incorporating surface-ionized ion thermoemitter by values of ΔU, Kpc, and Uc and shape of collector ion current peak including thermoemitter current Ite. |
 Ion spectrum measurement process and transit-time ion spectrometer / 2266587Charge and mass composition is measured by accelerating ions in accelerating gap formed in vacuum chamber between input end of drift tube and plasma when negative-polarity voltage pulse of length shorter than transit time in drift tube of accelerated ions of plasma being analyzed is applied to drift tube at maximal Z/Mi ratio, where Z is ion charge in plasma; Mi is ion mass. Voltage pulse is supplied from negative-polarity accelerating-voltage pulse source whose high-voltage lead is electrically connected to drift tube and other lead, to vacuum-chamber ground. When in transit, accelerated ions are divided within drift tube into mass, charge, and energy clots and separated clots are recorded by detector. |
 Method for analyzing ions by specific charges in hyperboloid mass spectrometer of type "three-dimensional trap" including introduction of ions being analyzed from outside / 2269179Proposed method for analyzing ions by specific charges in hyperboloid mass spectrometer of "three-dimensional ion trap" type includes introduction of ions into working space of analyzer, their entrapping by field, sorting out according to specific charges, followed by heir delivery to inlet of ion detector; ions are entrapped selectively by setting high-frequency supply voltage amplitude, and/or waveform, and/or frequency at which working point of ions being analyzed on stability diagram of at least one of coordinates on iso-β0 line corresponding to β0 =0 value, where β0 is parameter of stability. |
 Method for analyzing ions by specific charges in hyperboloid mass spectrometer of type "three-dimensional trap" including introduction of ions being analyzed from outside / 2269180Proposed method includes introduction of ions into working space of analyzer near its radial plane, their sorting out according to specific charges, and their delivery to ion detector input; parameters of high-frequency voltage applied to analyzer electrodes (waveform and/or amplitude, and/or frequency) are chosen so as to ensure that working point on one of coordinate axes of ions being analyzed is deep in stabilization zone and on other axis, near intersection point of mass spectrum line and stability zone boundary corresponding to β0 = +1, where β0 is parameter of stability. |
 Gas mixture analyzing device / 2272334Proposed device has gas mixture ionizer with ion-optic system, stigmatically focused mass-spectrometer, solid-state converter, electrostatic analyzer, and recording unit, all arranged in tandem along motion direction of particles. Converter is made of ultra-thin diamond-like foil disposed at 45 deg. to motion direction of particles and in same plane as one of plates of electrostatic analyzer made in the form of flat capacitor. Converter is enclosed by cylinder to form combined Faraday cylinder whose axis coincides with motion direction of particles; cylinder, converter, and electrostatic analyzer plate are electrically insulated from one another; input of charged-particles recorder is disposed in same electrostatic analyzer plate as converter. Charged-particles converter can be made in the form of amplifier on microchannel strip or in the form of set of secondary electronic multipliers. |
 Mode of measuring of a common concentration of carbon and hydrocarbon oxides in oxygen with the aid of spectrometry of mobility of ions / 2273847The mode includes the following operations: transformation of carbon and hydrocarbon oxide present in the flow of oxygen into dioxide; measuring of the concentration of carbon dioxide in oxygen after transformation; determination according to the results of measuring in accordance with the previous operation of the common initial concentration of carbon and hydrocarbon oxide. |
 Method and device for sorting out charged particles by specific charge / 2276426Mass analyzer built around confined ion trap and designed to improve consumer properties as well as to extend service life of mass spectrometers using hyperboloid electrode systems has hyperboloid butt-end electrode and plane-confined annular one, cylindrical shielding and focusing electrodes, as well as semitransparent flat correcting electrode. Charged particles are produced due to electron shock in space between annular and correcting electrodes beyond working space of mass analyzer. Ions are entered in analyzer under action of accelerating voltage across correcting and focusing electrode; period and phase of accelerating voltage are coordinated with those of variable field and with original coordinates and speeds of charged particles. Sorted out ions are brought out through annular electrode hole and through semitransparent correcting electrode under action of positive voltage across butt-end electrode. |
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Method and device for sorting out charged particles by specific charge / 2276426 Mass analyzer built around confined ion trap and designed to improve consumer properties as well as to extend service life of mass spectrometers using hyperboloid electrode systems has hyperboloid butt-end electrode and plane-confined annular one, cylindrical shielding and focusing electrodes, as well as semitransparent flat correcting electrode. Charged particles are produced due to electron shock in space between annular and correcting electrodes beyond working space of mass analyzer. Ions are entered in analyzer under action of accelerating voltage across correcting and focusing electrode; period and phase of accelerating voltage are coordinated with those of variable field and with original coordinates and speeds of charged particles. Sorted out ions are brought out through annular electrode hole and through semitransparent correcting electrode under action of positive voltage across butt-end electrode. |
FIELD: electricity.
SUBSTANCE: in a device for generation of ions, comprising an ionising chamber, including the first electrode, the second electrode arranged opposite to it, and a dielectric element installed between the first and second electrodes and tightly adjacent to the working surface of the first electrode, and also a source of high voltage, according to a utility model, the second electrode is arranged in the form of a metal cap, covering the dielectric element with the first electrode installed on it, besides, the bottom of the second electrode is arranged in the form of a grid, covered with a thin dielectric layer coated at both sides, the area of the working surface of the first electrode is commensurate to the maximum to the area of the grid of the second electrode, and the dielectric element is arranged in the form of the cap and is installed inside the second electrode.
EFFECT: higher efficiency of device operation, its increased service life due to increased service life of discharge electrodes, and higher stability of working characteristics of a device.
11 cl, 5 dwg
The invention relates to the field of gas analysis, in particular, to techniques for generating positively and negatively charged ions in the air or in other gases, and can be used as an ion source in ion mobility spectrometers, mass spectrometers and other analytical instruments.
Most prevalent among the sources of ions for ion mobility spectrometers (SIP) - based gas discharge received sources of ions in the corona discharge. In particular, the known ion sources for ion mobility spectrometry based on corona discharge under U.S. patent No. 5684300, No. 6100698, No. 6225623 that generation (ignition) corona discharge creates a strong inhomogeneous field in the interelectrode space, with one of the electrodes are in the form of spikes or thin wire of small diameter, typical sizes range from tens to hundreds of microns. Often use these types of geometry of the discharge, as the point-plane" or "tip-ring".
The main disadvantages of sources of ions in the corona discharge are their fragility and instability caused by the shape change and the subsequent destruction of the discharge electrode due process of cathode sputtering and oxidation of a metal by chemical substances produced in the poison, such as ozone, oxides of nitrogen, atomic radicals, etc.
Because of the small characteristic dimension of the discharge electrode in the form of the edge of even a slight change its shape leads to changes in the operating characteristics of the discharge, in particular, the discharge current, which is reflected in the analytical characteristics of the whole device.
Known ion source to the corona discharge for ion mobility spectrometers and mass spectrometers for U.S. patent No. 7326926, IPC H01J 49/00, G21G 4/00, publ. 05.02.2008, containing ionization chamber placed in her first corona electrode in the form of a set of edges and the second planar electrode with made a hole for the output of ions from the source.
This design corona elecrode partially solves the problem of increasing the service life of the ion source and stability of its work, the major deficiencies are not corrected. The processes of destruction of the metal electrode, characterized corona discharge, are also present in this source.
A device for generating ions in the gas (ion source), using barrier discharge and described in U.S. patent No. 7157721, IPC H01T 49/40; H01J 49/10; H01J 49/26, publ. 02.01.2007 historic contains a dielectric element in the form of plates, which from opposite sides attached electrodes differing in p is smeru. As is known, the shape and dimensions of the electrodes determine the parameters of the discharge and, consequently, the number of ions formed in the source. Alternatively, the structure in this patent, the electrodes are designed in the form of two disks of different diameters, placed on both sides of the dielectric plate. For the generation of ions to the electrodes is fed to the high-voltage pulse voltage.
This ion source has a longer service life compared with sources of ions in the corona discharge by increasing the size of the working electrode and the pulsed nature of the power of the discharge, due to the different mechanism of the category.
The disadvantages of the known device should be attributed to the presence of metallic contact of the working electrode with a gas environment, which is accompanied by the processes of oxidation and erosion of metal products discharge, which leads to the destruction of the metal electrode, and a small area of the working electrode, the consequence of which is the low efficiency of ionization of the gas medium.
The closest to the technical nature of the claimed is the ionization source for analytical instruments based barrier discharge by RF patent for the invention №2405226, IPC H01J 49/10, NT 23/00, publ. 27.11.2010, containing an ionization chamber comprising an inducing electrode, when replenis to the surface of the dielectric plate, and the corona electrode located opposite to the inducing electrode, and a source of high voltage pulses. The corona electrode is separated from the surface of the dielectric plate gas spaces of 10-100 μm, and an ionization chamber connected to the supply system cleaned gas, made with the possibility of regulation of the flow rate of the gas stream.
In this source, despite the presence of the dielectric plate in the interelectrode space between the electrodes occurs corona discharge. Therefore, the disadvantages noted above for the classical corona discharge, are also present in this device. This work (the corona) an electrode made in the form of a plate with holes having a tapered working edge, or in the form of a ring mounted in the working area of one or more thin metal wires exposed to erosion and sputtering, resulting in a gradual change of its form and further destruction, leading to unstable operation of the ion source and its subsequent failure.
In addition, a common drawback of all the above sources of ions on the basis of the gas discharge is the dependence of the discharge current from various disturbing factors, which include, in particular, change the group of the discharge current when changing the settings of the working gas (such as its composition, pressure, temperature, humidity), the current change due to instabilities electronics, modify the properties of the electrodes, for example, the sputtering of the electrodes, the contamination of the surface, etc.
These factors, together and separately, leads to uncontrolled changes in the magnitude of the discharge current and the output signal of the ion source, and consequently a violation of the stable of his work and the deterioration of characteristics of the entire device, in which the ion source is used.
The claimed invention solves the problem of creating an ion source for a gas-analyzing equipment, which would have increased ionization efficiency, longer service life and high stability performance.
The technical result from the use of the claimed invention is to improve the efficiency of the ionization source, the increase of life by increasing the service life of the discharge electrodes and the stability performance of the device by reducing the influence of a number of disturbing factors on the discharge current.
This technical result is achieved by the fact that the ionization source on the basis of the barrier discharge containing ionization chamber including a first electrode located on the on the second electrode, and a dielectric element mounted between the first and second electrodes and closely adjacent to the working surface of the first electrode, and a source of high voltage, according to the invention, the second electrode is made in the form of a metallic cap covering the dielectric element mounted on the first electrode, and the bottom of the second electrode is made in the form of a lattice, with both sides covered with a thin dielectric layer, the surface area of the first electrode maximum commensurate with the square lattice of the second electrode and the dielectric element is designed in the form of a cap and is installed inside the second electrode.
To increase the area of the working surface of the first electrode is made in the form of a metal sleeve with the disc placed on one end so that the drive electrode inside tightly to the inner bottom surface of the dielectric element.
In addition, the lattice of the second electrode is formed holes rounded, located on the perimeter of the lattice, and the holes are oblong in shape, located in the Central part of it.
In addition, the dielectric element and the dielectric layer of the second electrode is made of the same material.
In addition, to stabilize the discharge current source of high voltage on the order made in the form of the oscillator on the basis of the high-voltage piezotransformer voltage, contains the input section of the excitation with the third and fourth electrodes and the generator section to the output electrode, and is connected to consistently enabled bit interval, a current sensor, an amplifier, an output signal of a current sensor, a microcontroller, a digital frequency generator and amplifier output signal, the outputs of which are connected to third and fourth electrodes of the input section of the excitement.
In addition, the ionization source is further provided with an ion-molecule reactor, made in the form of a system of coaxial spaced alternating metal and dielectric ring electrodes, the longitudinal axis of which is aligned with the longitudinal axis of the first electrode. The first annular electrode metal ion-molecule reactor electrically connected with the second electrode of the ion source, and the outer diameter of the second electrode of the source does not exceed the inner diameter of the first annular metal electrode.
The invention is illustrated by drawings, which show: figure 1 presents a General view of the ion source to the barrier discharge (breakdown); figure 2 - the first metal electrode; figure 3 is a cross section of the second metal electrode; figure 4 General view of the second metal electrode; figure 5 shows a structural diagram high the voltage of the power source piezotransformer (VKT).
The ionization source includes an ionization chamber, which represents an ion-molecule reactor 1 holds bit device 2 installed in a common housing 3 and the source 4 high voltage (figure 1).
Bit device 2 includes a first high voltage metal electrode 5 connected to the rod by a pin 6 to summarize the high voltage, the second (inducing) metal electrode 7 and the dielectric element 8 located between the first 5 and 7 second metal electrodes and the insulator 9, mounted on the inner side of the dielectric element 8 and is designed to ensure a snug fit of the working surface of the first electrode 5 to the dielectric element 8.
To this end, the insulator 9 may be performed, for example, in the form of a Cup with a hole or sleeve of a dielectric material. In the embodiment, the insulator 9 may be a dielectric matrix, which filled the first electrode 5 so that when it is tight installation on the dielectric element 8 to completely eliminate the contact metal electrode with ionized air.
In the embodiment shown in the drawings, the first electrode 5 may be performed, for example, in the form of a metal sleeve 10, one end is toroi have a disk 11 to increase the area of the discharge surface, and the other end opening 12 for coupling to the high voltage contact 6, in particular, by means of the threaded connection (figure 2).
The second electrode 7 may be made in the form of a metal cap covering the dielectric element 8 is installed inside the first electrode 5 (figure 4). The bottom electrode 7 is its working surface is a grid with 13 made in her holes 14 of round shape, located on the perimeter of the lattice, and the holes 15 of the oblong form, located in the Central part of the base plate 13. The orifices 14 are intended for pumping of the sample gas, and the holes 15 for securing the combustion discharge.
To ensure maximum combustion space of the discharge, a necessary condition is the maximum proportion of the area of the working surface of the first electrode 5 with the square of the grating 13 and the second electrode 7.
The geometric dimensions of the grid 13 (width, height, and the distance between adjacent holes) are chosen experimentally and determine the magnitude of the ion discharge current and, thereby, the efficiency of ionization.
In the production version of the device, the grating 13 may be formed and the other configuration and relative position of the holes, for example, in the form of interlaced rows of wire, or to have the cellular structure of the ur.
The lattice surface 13 of the electrode 7 on both sides covered with a thin layer 16 of dielectric, which allows to increase service life of the electrode by eliminating the processes of destruction of the metal electrode due to erosion and oxidation upon contact with ionized air (figure 3).
In the production version, the optimum thickness of this layer 16 is, for example, of the order of 10-20 microns; the thicker the dielectric layer will complicate the ignition of the discharge, and the layer is less than 10 μm will lead to reduced service life of the electrode.
The dielectric element 8 can also be made in the form of a cap of dielectric material mounted on the first electrode 5 so that the disk 11 of the electrode 5 from the inside densely adjoined to the bottom of the insulator dielectric element 8.
The dielectric material from which is made of a dielectric element 8, separating the metal electrodes 5 and 7, and its thickness determine the magnitude of the discharge current. While it is desirable that the dielectric element 8 and the dielectric layer 16 of the second electrode 7 were made of the same material, which can be used, for example, corundum ceramics, glass, quartz, polymeric material, etc.
When assembling the source of ionization discharge device 2 is positioned so that the first electrode 5, is placed in NR the internal cavity of the insulator 8 and the fixed insulator 9, inserted into the internal cavity of the second electrode 7 and using the screw connections on the pivotal pin 6 is fixed in the insulator 17, vmontirovana in case 3.
Ion-molecule reactor 1 is functionally designed for drawing ions from the discharge and transportation to the outlet of the source, i.e. for the formation of ion flow, and is made in the form of a system of alternating metal 18 and the dielectric 19 coaxial annular electrodes fastened together, for example, by soldering or gluing. In the production version of the device shown in the drawings, the dielectric ring electrode 19 made of ceramics and consistently fused with metal electrodes 18. The dimensions of annular electrodes 18 and 19 are selected so as to create within the system of homogeneous field directed along its longitudinal axis. Metal electrodes 18 are connected between a high resistance divider (not shown)intended for supply voltage on ion-molecule reactor 1.
Ion-molecule reactor 1 is installed in the insulator 17 of the housing 3 so that the longitudinal axis system of ring electrodes 18 and 19 passing through the center of the disk 11 of the electrode 5, i.e. coincident with the longitudinal axis of the discharge device 2. The first annular metal electrode 18 of the ion-molecularstructure 1 is electrically connected with the second electrode 7 bit device 2. While in the embodiment of the device shown in figure 1, the outer diameter of the second electrode 7 does not exceed the inner diameter of the first annular electrode 18 to provide a snug installation in one another.
In addition, the housing 3 of the declared source of ionization performed the opening 20 to enter the gas in the ion-molecule reactor 1 and the outlet 21 for o ions and the flow of gas, which is the outlet of the ionization source and can be directly coupled to the ion mobility spectrometer or, with additional input devices, mass-spectrometer.
Source 4 high voltage (figure 5) is made in the form of a free-running oscillator on the basis of the high-voltage piezotransformer (VKT) 22 voltage containing the input section of the excitation 23 with the third 24 and fourth electrodes 25 and the generator section 26 with the output electrode 27.
In addition, the voltage source 4 also includes series-connected current sensor 28, an amplifier 29 and the output signal of the current sensor 28, the microcontroller 30, a digital frequency generator 31 and the amplifier 32 output signal, the outputs of which are connected to the third 24 and fourth electrodes 25 of the input section of the excitation 23. The output electrode 27 piezotransformer 22 connected to the first electrode 5 bit device is VA 2, and the second electrode 7 bit device 2 is connected through a capacitive isolation (for example, high-voltage capacitor with a current sensor 28.
Digital frequency generator 31 is designed to generate the input pulse piezotransformer 22 with a frequency close to the resonant frequency, which is then amplified by amplifier 32 and fed to a third 24 and fourth electrodes 25 of the input section of excitation of 23.
The current sensor 28, an amplifier 29 and the output signal of the current sensor 28 and the microcontroller 30 form a chain, intended to stabilize the discharge current.
The ionization source is as follows.
The gas mixture is fed through the opening 20 in the housing 3 in the discharge device 2 and pumped through ion-molecule reactor 1 in the direction of the outlet 21.
On resistive divider ion-molecule reactor 1 from the external voltage source serves a constant high voltage of a certain polarity. The magnitude of this voltage is selected in accordance with the system configuration of the ring electrode (geometrical dimensions and the number of ring electrodes 18 and 19) to create inside the ion-molecule reactor 1 homogeneous constant field values of the order of 200 to 300 V/cm, directed along the axis of the ring electrodes 18 and 19 of the discharge device 2 to the outlet 21 of the light source, the CA ions.
High-voltage AC voltage with a frequency of 80 kHz, the amplitude of the order of 3-3 .5 kV source 4 high voltage is applied to the electrodes 5 and 7 of the discharge device 2. Between working surface (grating 13) of the second electrode 7 and the dielectric element 8 occurs barrier discharge, and ions are formed molecules of the analyzed substances and air.
Under the action of a constant field created by the ring electrode ion-molecule reactor 1, depending on the polarity of the applied voltage, ions of a particular polarity are extruded from the discharge goes into the ion-molecule reactor 1 and are moving towards the outlet 21 of the ion source. As the movement of ions in the ion-molecule reactor 1 may be additional ionization of the investigated substances in ion-molecular reactions between educated in the discharge of air ions and molecules of the analyzed substances. When this ion-molecule reactor 1 can increase the residence time of the analyzed substances in the ion source, thereby increasing the number of generated ions of the analyzed substances. Then through the outlet 21 ions are served in the analytical device.
Source 4 high voltage on the TPP operates as follows. Digital frequency generator 31, are connected the external voltage source, generates pulses with a frequency close to the resonant frequency of piezotransformer 22. Then these pulses are amplified by amplifier 32 and supplied to the third and fourth electrodes 24 and 25, respectively. On the output electrode 27 piezotransformer 22 is formed sinusoidal voltage of the order of 3-3 .5 kV. This voltage is proportional to the amplitude and frequency of the pulses at the electrodes 24 and 25 from the amplifier 32 output signal.
For stabilizing the discharge current using a current sensor 28, an amplifier 29 and the output signal of the current sensor 28 and the microcontroller 30. The discharge current is proportional to the voltage at the output electrode 27 piezotransformer 22. While the current sensor 28 generates a signal proportional to the discharge current, which is amplified by amplifier 29 and then fed to the ADC of the microcontroller 30 through which the input signal is digitized, the current value of the discharge current is compared with a given (fixed in the memory of the microcontroller 30), and on the comparison of the digital frequency generator 31 are control signals for frequency adjustment. Changing the pulse repetition frequency digital frequency generator 31 leads to a change in voltage at the output electrode 27 piezotransformer 22, and hence to a proportional change of the discharge current.
Thereby use is of the TPP 22 allows for low input voltage (e.g., 5) to obtain the output high voltage of about 3 kV, which reduces power consumption of the device and can be used in compact devices with low power consumption.
The use of the ion source can increase the lifetime of the analytical device, in particular, in comparison with the sources in the corona discharge, to reduce its size and power consumption, eliminating the need for periodic calibration and adjustment of equipment, replacement parts source, failed to reduce size and power consumption of the analytical device, and to improve the sensitivity and reliability analysis.
The efficiency of the ionization source is due to the inclusion in the composition of the ion source ion-molecule reactor, which allows you to increase the residence time of the analyzed substances in the ion source, thereby increasing the number of generated ions of the analyte, and also performs the function of drawing ions from the discharge and transport to the outlet of the source, i.e. the formation of ion flow.
The floor of the inducing electrode thin dielectric layer makes it possible to eliminate the oxidation and erosion of the metal electrodes, leading to their destruction, and thereby also to increase the service life of IP the student ions. A special form of discharge electrodes used in the claimed device, allows for more efficient ionization of the molecules of the gas environment. Implementation mode discharge with current regulation allows to reduce the fluctuation of the magnitude of the discharge current, thereby increasing the stability of the operating characteristics of the ion source.
1. Device for producing ions in a gas environment containing an ionization chamber including a first electrode opposite a second electrode and a dielectric element mounted between the first and second electrodes and closely adjacent to the working surface of the first electrode, and a source of high voltage, wherein the second electrode is made in the form of a metallic cap covering the dielectric element mounted on the first electrode, and the bottom of the second electrode is made in the form of a lattice, with both sides covered with a thin dielectric layer, and the surface area of the first electrode maximum commensurate with the square lattice of the second electrode.
2. The device according to claim 1, wherein the dielectric element is designed in the form of a cap and is installed inside the second electrode.
3. The device according to claim 1, characterized in that to increase the area of the working surface of the first electrode is he the imp is replaced in the form of a metal sleeve with the disc, posted on one end so that the drive electrode inside tightly to the inner bottom surface of the dielectric element.
4. The device according to claim 1, characterized in that the lattice of the second electrode is formed holes rounded, located on the perimeter of the lattice, and the holes are oblong in shape, located in the Central part of it.
5. The device according to claim 1, characterized in that the dielectric element and the dielectric layer of the second electrode is made of the same material.
6. The device according to claim 1, characterized in that in order to stabilize the discharge current source of high voltage in the form of free-running oscillator on the basis of the high-voltage piezotransformer voltage.
7. The device according to claim 6, characterized in that the high-voltage piezotransformer voltage contains the input section of the excitation with the third and fourth electrodes and the generator section with the output electrode and is connected to consistently enabled bit interval, a current sensor, an amplifier, an output signal of a current sensor, a microcontroller, a digital frequency generator and amplifier output signal, the outputs of which are connected to third and fourth electrodes of the input section of the excitement.
8. The device according to claim 1, characterized in that it is additionally equipped with a lithium-Molek is popular reactor made in the form of a system of coaxial spaced alternating metal and dielectric ring electrodes.
9. The device according to claim 8, characterized in that the longitudinal axis of the ion-molecule reactor is combined with the longitudinal axis of the first electrode.
10. The device according to claim 8, characterized in that the first annular electrode metal ion-molecule reactor electrically connected with the second electrode of the device.
11. The device according to claim 8, characterized in that the outer diameter of the second electrode of the source does not exceed the inner diameter of the first annular metal electrode.