RU197959U1 - DEVICE FOR RESEARCH OF SUBSTANCE COMPONENTS USING MICROWAVE PLASMA BY OPTICAL AND NMR SPECTROSCOPY METHODS - Google Patents

Abstract

The utility model relates to the field of research and analysis of materials. A device for studying the components of a substance is proposed, which includes series-connected blocks: the first block of the atomizer and the spray chamber, the second block of a plasma torch with a magnetron, and the third block of the system of sampling cones, electrostatic lenses, and mirrors. In this third block, microwave plasma is divided into a stream of light and a stream of ions. The light is directed through a mirror to an atomic emission spectrometer (AES spectrometer), and the ion flux passes through holes in the sampling cone system and then is sent to an NMR spectrometer using electrostatic lenses. All of these blocks are connected to a computer that controls their work, and also stores and processes the results of the NMR spectrometer and AES spectrometer using a common computer program. The technical result achieved consists in the possibility of obtaining NMR and atomic emission spectra of the test substance at the same time, which allows a more reliable and accurate study of the sample, eliminating ambiguities and difficulties in decoding the NMR spectrum. 1 ill.

Description

The technical field to which the utility model relates.

The proposed utility model relates to the field of research and analysis of materials, and in particular to a device for the study of substances using nuclear magnetic resonance (NMR) spectroscopy (elemental, isotopic, structural) and atomic emission spectroscopy (nuclear) (elemental, structural) methods using microwave plasma (MP). This device combines two independent methods: nuclear magnetic resonance spectroscopy with microwave plasma (NMR-MP) and atomic emission spectroscopy with microwave plasma (AES-MP).

State of the art

From the prior art [Robert S. Houk et. al. Inductively coupled argon plasma as an ion source for mass spectrometric determination of trace elements / Analytical Chemistry, 1980, V. 52, N. 14, pp. 2283-2289] known device mass spectrometer with inductively coupled plasma, which, in essence, is an NMR spectrometer with inductively coupled plasma [Becker J. Spectroscopy / TRANS. with him. - M .: Technosphere, 2017, 528 p., P. 225]. In the domestic literature, such a device is known as a mass spectrometer with ion cyclotron resonance, which has the highest resolution in mass spectrometry.

The disadvantage of this device is the impossibility of obtaining the atomic emission spectrum of the test sample.

A microwave plasma differs from an inductively coupled plasma in a lower limit temperature (up to about 6000 ° K), but can also be used to operate an NMR spectrometer.

Moreover, the device of an optical spectrometer with a microwave plasma [Ng K.C., Garner T.J. Microwave Induced Plasma Atomic Absorption Spectrometry with Solution Nebulization and Desolvation-Condensation / Applied Spectroscopy, 1993, V. 47, No. 2, pp. 241-243].

As a disadvantage of this device, it is necessary to note the impossibility of obtaining the NMR spectrum of the test sample.

Utility Model Disclosure

The technical result of the proposed utility model is the possibility of obtaining NMR spectra and the atomic emission spectrum of the test substance at the same time, which allows more reliable and accurate study of the sample, eliminating ambiguities and difficulties in decoding the NMR spectrum. These ambiguities and difficulties in the NMR spectrometer with MP can be eliminated or reduced with the help of information obtained from decoding the AES-MP and processing this information using a computer program that takes into account the results of the operation of the NMR-MP and AES-MP.

The specified technical result is achieved by the device for studying the component of the substance proposed in this application, which includes series-connected blocks: the first block of the sprayer and the spray chamber, the second block of the plasma torch with a magnetron and the third block of the sampling cone system, electrostatic lenses and mirrors, while in the third In the unit, the microwave plasma is divided into a stream of light, which is sent through a mirror to an atomic emission spectrometer (AES spectrometer), and to an ion stream, which passes through holes in the system of sampling cones and then is sent to an NMR spectrometer using electrostatic lenses. All of these blocks are connected to a computer that controls their work, and also stores and processes the results of the NMR spectrometer and AES spectrometer using a common computer program.

Brief Description of the Drawing

In FIG. 1 presents a structural diagram of the proposed device. The device includes: a sprayer and a spray chamber (block 1); plasma torch with magnetron (block 2); a system of sampling cones, electrostatic lenses and mirrors (block 3); NMR spectrometer (block 4); AES spectrometer (block 5); computer (block 6).

Utility Model Implementation

Blocks 1, 2, 3 and 4 are interconnected vacuum tightly, connected to a fore-vacuum and high-vacuum pumping system, equipped with a valve system that allows you to adjust the pressure in each of them, as well as measure it using appropriate devices. AES spectrometer (block 5) operates at atmospheric pressure. All blocks are connected to a computer 6, which controls the operation of each block, remembers the results of the NMR spectrometer and nuclear power spectrometer, and then decrypts and processes them together according to a single program.

The test sample enters the atomizer, and then into the spray chamber (block 1). From the spraying chamber, the aerosol is transferred by a carrier gas stream to a cassette-type plasma torch (block 2). Nitrogen from air can be used as a carrier gas, which can be obtained using a nitrogen generator, which is much cheaper than using Ar or He. In a plasma torch (block 2), plasma is excited using a magnetron. The magnetron is similar to that used in household microwave ovens and is produced by industry in large quantities for them, and therefore is many times cheaper than high-frequency generators for inductively coupled plasma. A magnetron’s magnetic field with a frequency of ~ 2450 MHz creates lines of magnetic induction that coincide with the axis of the plasma torch, and the lines of force of the electric field are directed perpendicular to the magnetic. This leads to the production of a stable microwave plasma with temperatures up to 6000 ° K, which makes it possible to obtain the atomic emission spectrum of elements more easily than when working with inductively coupled plasma. Then, in block 3, the light radiation of the MP by a mirror (fixed in space to the system of sampling cones) is sent to the NPP spectrometer (block 5). The arrangement of the mirror to the sampling cones gives a much larger light flux to the NPP spectrometer, compared to the option when the mirror is located after the sampling cone system, since the diameter of the hole in the cones is of the order of a millimeter.

AES spectrometer (block 5) operates at atmospheric pressure, and an NMR spectrometer (block 4) operates at a pressure of the order of 10 ^-4 Pa. For this reason, a light beam exits block 3 through a light guide material (quartz, sapphire), which vacuum separates block 3 and block 5 through the gaskets tightly. Block 3 is sealed, pumped by forevac and high vacuum pumps. At the same time, in block 3, the plasma ion flow passes through a system of sampled cooled cones with holes in the vertices between which a step-by-step pumping is carried out: first at the forevacuum (up to about 0.1 Pa) and then at high vacuum (up to about 10 ^-4 Pa) . Plasma ions pass through the holes at the tops of the sampling cones (the so-called samplers and skimmers), and then are sent to the NMR spectrometer using a system of electrostatic lenses (so-called omega lenses) (block 4). A rectilinear light beam passing through thin holes at the tops of the sampling cones (with a diameter of the order of tenths of a millimeter) is attenuated and extinguished, falling into the damper. The results of the AES spectrometer (block 5) and the NMR spectrometer (block 4) are stored by a computer (block 6) and enter the program for joint processing of data obtained simultaneously by two methods, which significantly increases the reliability and accuracy of the sample analysis.

Microwave plasma nuclear magnetic resonance spectroscopy (NMR-MP) has an advantage over microwave plasma atomic emission spectroscopy (AES-MP) due to the higher sensitivity and stability of the NMR spectrum and a wider range of sample concentrations. Moreover, in the NMR-MP method, there are also many problems associated with isobaric interference, polyatomic overlays, two and multiply charged ions, resolution, etc. For this reason, additional information from NPP-MP will reduce these problems and increase the detection limits of elements.

Claims (1)

A device for examining the components of a substance, characterized in that it includes serially connected the first block of the atomizer and the spray chamber, the second block of the plasma torch with a magnetron and the third block of the system of sampling cones, electrostatic lenses and mirrors, and in this third block the microwave plasma is divided into a stream light, which is directed through a mirror to an atomic emission spectrometer (AES spectrometer), and to an ion stream that passes through openings in the system of sampling cones and then, using electrostatic lenses, is sent to a nuclear magnetic resonance spectrometer (NMR spectrometer), moreover all of these blocks are configured to connect to a computer configured to control their operation and process the results of the NMR spectrometer and nuclear power spectrometer.

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