KR20210020736A - Electronic nose apparatus and method using spectrum analysis - Google Patents

Abstract

Through the present invention, electronic nose technology of the following process is provided. An electronic nose is implemented in such a manner that firstly, a gaseous sample is dissolved in a solvent in an impinger and a sample dissolved in the solvent is introduced into an RF resonator so as to induce a change in physical/chemical properties of the sample solution, and secondly, RF or electromagnetic waves with various absorption spectrum characteristics for each material in the RF resonator are generated so as to determine the type of a gas through the spectrum analysis, Accordingly, the limitations (number of channels) of the resolution of GC and sensor array and the need for multi-channel sensors can be overcome. In addition, a time required for spectrum analysis is limited to 1-2 seconds so as to enable analysis to be performed virtually in real-time, and thus, the present invention can be applicable for industrial and research use, and the present invention can easily analyze various types of odor without the replacement of a part or a sensor of a conventional facility.

Description

Electronic nose apparatus and method using spectrum analysis

The present invention relates to a technique for implementing an electronic nose using electromagnetics, electronic and electrical engineering, medical engineering, and material engineering techniques.

The human nose is a very sensitive organ among the sense organs, and it works by acquiring information about gaseous chemicals. However, the human nose basically has a relatively short detection time, and in particular, when a person directly tests a toxic substance, it is a threat to human health. In addition, the human nose cannot be an objective indicator because it has no resolution for the composition of chemical substances, and it depends only on the feeling and memory of the person in charge. However, in the food and cosmetic (cosmetics) industry, fragrance is a very important factor, and in order to use it industrially, it is very important to establish consistent and scientific data.

Accordingly, in many sectors, efforts have been made to develop devices called'electronic noses', and some are sold in the market. Until now, electronic noses can be divided into two types. One of the existing chemical analysis equipment, 1) Gas Chromatography (GC) or GC-mass spectrometry, is used as it is and liquid phase. Equipment adapted for gaseous sample injection, or 2) Profiling data by combining a sensor (or sensor array) reacting to gaseous substances and a vapor control device (e.g. gas pump) to data the response to the sensor It can be divided into types of obtaining (profiling data).

GC or GC mass is very expensive in the equipment itself, and high-pressure gas is passed through a GC-column (passed within minutes to hours) and measured by mass or time by a general detector. There is a problem that the data must be used, and interpretation of the data is not possible without highly educated professionals.

In the case of an electronic nose using a sensor array, the aromatic substance itself is composed of as few as a few to several thousand kinds of compounds, whereas there are only a few dozen types of sensors that can be installed. There are significant restrictions on application.

Two problems of the existing electronic nose through the present invention, namely, 1) a fundamental problem of GC or GC mass analysis using a GC column (a problem that has to deal with an analysis time of several tens of minutes to several hours and expensive/high pressure gas) And 2) to solve the problem that cannot be used for various purposes due to the limitation of the number of sensors.

In order to solve the above problem, the electronic nose technology of the following process is provided.

1) The gaseous sample is dissolved in the solvent in the impinger, and the sample dissolved in the solvent is injected into the RF resonator to induce the physical/chemical properties of the sample solution to change.

2) In the RF resonator, RF or electromagnetic waves with various absorption spectrum characteristics are generated for each substance, and the type of gas is determined through this spectrum analysis to realize an electronic nose.

Specifically, the electronic nose device based on spectrum analysis according to the present invention receives a test sample to measure odor, and generates a resonate action on the input sample by using an applied RF. An RF resonator that outputs RF having a spectrum; And a signal generator/analyzer for applying RF into the RF resonator and receiving and analyzing RF output through a resonate action in the RF resonator.

In addition, the electronic nose device based on spectrum analysis according to the present invention may further include an impinger for discharging a liquefied sample to the RF resonator by concentrating a gaseous test sample to measure the odor in a liquid solvent.

In addition, the electronic nose device based on spectrum analysis according to the present invention may further include an air pump supplying air to the impinger to discharge a sample liquefied in the impinger.

This overcomes the limitations of the resolution of GC and sensor array and the need for multi-channel sensors (number of channels). In addition, since the spectrum analysis time is limited to within 1 to 2 seconds, it is possible to analyze in real time, so it can be applied for industrial and research purposes, and various kinds of fragrances can be easily analyzed without replacing the accessories or sensors of existing facilities.

The configuration and operation of the present invention introduced above will become more apparent through specific embodiments described with reference to the drawings.

The present invention does not use expensive equipment such as GC Mass Spectrometry (GC-MS), which is the basic technology of the existing electronic nose, and does not use GC columns and carrier gases necessary for operation. The cost and operating cost of the system become very cheap Compared to the array sensor system, which can be called another basic type of electronic nose, the present invention has advantages in equipment price and operation by using various frequencies generated from an RF resonator without using multiple sensor systems. . In addition, by replacing the solution in the impinger, an optimal analysis suitable for the properties of the gaseous substance becomes possible.

1 is a configuration diagram of the entire system
2 is a configuration diagram of an impinger
3 is a configuration diagram of an RF resonator
4 to 8 are experimental materials and result graphs of the present invention

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms different from each other, only this embodiment makes the disclosure of the present invention complete, and those skilled in the art to which the present invention pertains. It is provided to fully inform the scope of the invention to the person, and the invention is defined by the description of the claims.

On the other hand, terms used in the present specification are for explaining examples and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated in the phrase. As used herein, “comprise” or “comprising” means the presence of one or more other components, steps, actions and/or elements other than the recited component, step, operation and/or element, or Does not rule out addition.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to elements of each drawing, even though they are indicated on different drawings, the same elements are assigned the same reference numerals as much as possible, and in describing the present invention, a detailed description of related known configurations or functions If the gist of the present invention may be obscured, a detailed description thereof will be omitted.

1 is an overall system configuration diagram of an electronic nose device according to the present invention.

A sample container 10 containing a gas to be tested to smell it with an electronic nose; An impinger 20 for concentrating a gaseous sample contained in the sample container 10 in a liquid solvent; An air pump 40 for supplying air to the impinger 20 in order to discharge the sample liquefied in the impinger 20 (to be precise, to be introduced into the RF resonator 30 to be described later); An air regulator 41 such as a valve and a nozzle for controlling the amount of the sample discharged from the impinger 20 by controlling the amount of air discharged from the air pump 40; In order to measure a gaseous sample concentrated in a solvent in the impinger 20, a sample injected from the impinger 20 is received, and a resonate action on the input sample is applied using an applied RF (electromagnetic wave or microwave). An RF resonator 30 for outputting an RF having a spectrum generated corresponding to the input sample by generating a resultant And a signal generator/analyzer 50 that inputs RF into the RF resonator 30 and receives and analyzes RF that has undergone a resonate action in the RF resonator 30.

2 is a configuration diagram of an embodiment of the impinger 20.

The impinger 20 is a kind of glassware having a structure in which the sample material flowing into the sample inlet 21 (from the sample container 10) in the gaseous phase is dissolved in the liquid solvent 22. As the solvent 22 for dissolving the gaseous sample, water is used when the sample is water-soluble, and acetone is used when the sample is oil-soluble.

The sample dissolved in the solvent 22 in the impinger 20 and liquefied is introduced into the RF resonator 30 from the sample outlet 24 through the sample inlet of the RF resonator 30 (see 31 in FIGS. 3A and B). . For injection of the sample, air is injected into the air inlet 23 of the impinger 20 by the air pump 40 shown in FIG. 1. The amount of air injected at this time is made through the air regulator 41 (nozzle or valve) of the air pump 40.

3A and 3B are configuration diagrams of an embodiment of the RF resonator 30, FIG. 3A is a plan view, and FIG. 3B is a front view.

In this embodiment, the RF resonator 30 is made of a metal such as aluminum or brass and has a substantially cylindrical shape. It is manufactured in a shape so that RF, such as electromagnetic waves applied to the inside, cannot escape to the outside and forms a specific mode inside.

Specifically, the sample inlet 31 through which the sample is injected from the impinger 20 shown in FIG. 1 into the sample, and the RF receiving end 32 through which RF, such as electromagnetic waves, is input from the signal generator/analyzer 50 shown in FIG. , And an RF transmitting end 33 that outputs RF from the RF resonator 30 and sends it to the signal generator/analyzer 50.

RX and TX antennas are connected to the RF receiving end 32 and the RF transmitting end 33, respectively, and connected to the signal generator/analyzer 50. The connection between the RX and TX antennas and the signal generator/analyzer 50 is made by wire or wireless.

In the case of wired, it may be in the form of a cable connected to the RF-Out terminal 51 and the RF-In terminal 52 of the signal generator/analyzer 50 (34 and 35 in Fig. 1), and in the case of wireless, an example For example, it may be in the form of a circular antenna (eg, a loop antenna) having a diameter of 3 to 5 cm with a wire coated with enamel on a copper wire core.

In the case of the wireless antenna, in the case of manufacturing a circular antenna using a metal wire, it is preferable to manufacture such that the diameter is less than the maximum width (maximum diameter) of the wing of the RF resonator 30 (at this time, the antenna Should not touch the metal surface of the RF resonator (30). In another embodiment, in the case of a wireless antenna, a known broadband antenna may be used.

Meanwhile, the signal generator/analyzer 50 supplies RF of a specific region (8 GHz to 35 GHz in the present invention) required for resonate driving of the RF resonator 30 to the RF resonator 30. In this case, RF may be supplied to the RF resonator 30 in a predetermined frequency unit (for example, in 1 Hz unit). Then, the absorption rate of the spectrum of RF received from the RF resonator 30 is analyzed. S21 mode can be used for analysis.

As the signal generator/analyzer 50, a vector network analyzer (VNA) may be used. However, in other specific situations, similar results can be obtained by using a scalar network analyzer (SNA) that does not carry phase information.

<Verification experiment>

In order to verify the spectrum analysis-based electronic nose apparatus and method according to the present invention, two commercially available fragrances, winter green fragrance and camphor fragrance (see FIG. 4) were prepared as samples.

By configuring the system as shown in FIG. 1, a sample dissolved in a solvent in the impinger 20 without any pretreatment (acetone was used as a solvent to dissolve the two gaseous samples) was converted into an RF resonator using the air pump 40 for 30 seconds. It was put into (30). The sample input was stopped, and the wavelength range of 5 to 6 GHz was divided into 10 MHz units using a VNA with a signal generator/analyzer 50 and sweeping was performed.

As a result of the above, the spectrum distribution results of Camper and Wintergreen were obtained as shown in FIG. 5 (the x-axis is the RF frequency, and the y-axis is the signal intensity). In the overall spectrum of FIG. 5, only differences between these samples can be confirmed, but detailed information can be obtained as follows by dividing various frequency domains.

6 shows the results of direct comparison between acetone (solvent) and camphor flavor and winter green flavor in the 35-37 GHz region.

7 is a comparison graph of a value obtained by subtracting the intensity of acetone (solvent) from the camphor flavor and the winter green flavor in the 51-60 GHz region.

FIG. 8 is a graph of the results after subtracting the camphor flavor from the winter green flavor in the graph of FIG. 7. It shows the difference in intensity compared for each frequency.

Above, the configuration of the present invention has been described in detail through a preferred embodiment of the present invention, but those of ordinary skill in the art to which the present invention pertains, the present invention is disclosed in the present specification without changing the technical spirit or essential features. It will be appreciated that it may be implemented in a specific form different from that of. It should be understood that the embodiments described above are illustrative in all respects and not limiting. The scope of protection of the present invention is determined by the claims described later rather than the detailed description, and all changes or modifications derived from the scope of the claims and their equivalent concepts should be interpreted as being included in the technical scope of the present invention. .

Claims (18)

An RF resonator for receiving a test sample for measuring odor and generating a resonate action on the input sample using the applied RF to output RF having a spectrum generated corresponding to the input sample; And
A spectrum analysis-based electronic nose apparatus comprising a signal generator/analyzer that applies RF into the RF resonator and receives and analyzes RF output through a resonate action in the RF resonator. The electronic nose apparatus according to claim 1, further comprising an impinger for concentrating the gaseous test sample for measuring the odor in a liquid solvent to discharge the liquefied sample to the RF resonator. The electronic nose device based on spectrum analysis according to claim 2, further comprising an air pump supplying air to the impinger to discharge the sample liquefied in the impinger. The method of claim 2, wherein the solvent used in the impinger is
When the sample is water-soluble, water, and when the sample is fat-soluble, acetone is used. The electronic nose apparatus based on spectrum analysis according to claim 1, wherein the RF resonator is manufactured to form a preset mode inside without allowing the RF applied to the inside to escape to the outside. The electronic nose apparatus according to claim 1, wherein the RF applied to the RF resonator has a frequency range of 8GHz to 35GHz. The method of claim 1, wherein the RF resonator is
A sample inlet through which a sample is injected from the impinger into the inside,
An RF receiving end to which RF is applied from the signal generator/analyzer to the inside,
An electronic nose device based on spectrum analysis, comprising an RF transmitter that outputs resonated RF and sends it to the signal generator/analyzer. The method of claim 1, wherein the RF applied to the RF resonator is applied to the RF resonator from the signal generator/analyzer through an RX antenna, and the RF output from the RF resonator is transmitted to the signal generator/analyzer through a TX antenna. Characterized in that, spectrum analysis-based electronic nose device. The electronic nose apparatus according to claim 8, wherein the RX and TX antennas are wired cables. The electronic nose apparatus according to claim 8, wherein the RX and TX antennas are wirelessly connected to a signal generator/analyzer. The electronic nose apparatus according to claim 8, wherein the RX and TX antennas are circular antennas that are wirelessly connected to a signal generator/analyzer, and have a diameter less than the maximum width of the RF resonator. The method of claim 1, wherein the signal generator/analyzer
Analyzing the absorption rate of the RF spectrum output from the RF resonator, characterized in that using the S21 mode during the analysis, spectrum analysis-based electronic nose device. The method of claim 1, wherein the signal generator/analyzer
An electronic nose device based on spectrum analysis, characterized in that it is one of a vector network analyzer (VNA) and a scalar network analyzer (SNA). An RF resonate step of receiving a test sample for measuring odor and receiving RF, generating a resonate action on the input sample to output RF having a spectrum generated corresponding to the input sample; And
And analyzing a spectrum by receiving the RF output through the resonate action. The method of claim 14, wherein the test sample that is introduced into the RF resonate step
A method for implementing an electron nose based on spectrum analysis, characterized in that the gaseous sample is a sample that is concentrated in a liquid solvent and liquefied. The method of claim 14, wherein the RF resonate step
A method for implementing an electronic nose based on spectrum analysis, characterized in that it is implemented in an RF resonator manufactured to form a preset mode inside without allowing the RF applied to the inside to escape to the outside. The method of claim 14, wherein the RF applied to the RF resonate step is in a frequency range of 8 GHz to 35 GHz. The method of claim 14, wherein the spectrum analysis step
Analyzing the absorption rate of the RF spectrum output from the RF resonate step, characterized in that the S21 mode is used during the analysis, spectrum analysis-based electronic nose implementation method.

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