Analytical device

Abstract

This invention provides an analytical device capable of analyzing trace amounts of odor molecules contained in a gas. [Solution] An analytical apparatus 50 comprising: an odor cell 1 for capturing odor molecules 5, which is made of a porous material 3 whose surface is coated with a ceramic material 2; a gas flow case 10 for housing the odor cell 1; a generating unit 40 for generating electromagnetic waves of a specific wavelength; a detection unit 43 for irradiating the odor cell with these electromagnetic waves by passing them through a first window member 20 of the gas flow case 10, and detecting the electromagnetic waves that have been transmitted or reflected and then passed through a second window member; and a processing unit 44 for processing the detection signal output from the detection unit to obtain information about the odor molecules 5.

Description

Technical Field

[0001] The present invention relates to an analyzer capable of analyzing the components of trace odor molecules contained in a gas.

Background Art

[0002] Conventionally, as a method for performing component analysis, structural analysis, and quantification of a sample by irradiating a substance with electromagnetic waves and measuring the transmitted or reflected electromagnetic waves, spectroscopy using ultraviolet light, visible light, or infrared light is known, and spectroscopic devices (analyzers) to which this spectroscopy is applied are widely used. In recent years, in addition to these, a new spectroscopy called terahertz time-domain spectroscopy (THz: time-domain spectroscopy, THz-TDS), which uses electromagnetic waves in the frequency range of 0.1 to 10 THz, has also emerged. In the future, spectroscopic devices applying this spectroscopy are expected to be used as advanced analyzers in various fields such as materials, food, and medical fields.

[0003] For example, an analyzer for analyzing a gas using terahertz waves or infrared light is disclosed in Patent Document 1. In this Document 1, it is shown that a capture film for capturing a gas is separated from a site (such as skin) that generates the gas, and the gas captured by this capture film is made to interact with terahertz waves or infrared light for analysis. And this capture film is a porous polymer, and materials with low loss in terahertz waves, for example, polymer-based porous materials such as polyethersulfone, nylon, polypropylene, polysulfone, Teflon (registered trademark), polyolefin, polyethylene, polystyrene, and ethylene tetrafluoride are mentioned. The pores inside this porous material are connected to each other, and generally, such a material is sometimes referred to as a sponge-shaped material. Also, the average diameter of the pores of such a porous material is desirably, for example, several tens of μm or less, which is sufficiently smaller than the wavelength of terahertz waves when using terahertz waves.

[0004] Furthermore, in the medical field, for example, Patent Document 2 discloses a special porous layer in which the target of analysis can be selected and / or concentrated at the sampling stage by using a porous adsorption layer with a pore size suitable for the adsorption of molecules, bacteria, viruses, and cells. The adsorption layer further discloses a special porous layer in which at least three porous layers with different central pore sizes are stacked in order of decreasing average pore size from 0.1 to 1000 nm from the sampling side. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2010-169658 [Patent Document 2] International Publication No. WO2012 / 056729 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, even when using capture membranes or capture layers that combine multiple types of porous polymer materials as described above, it is often impossible to capture a sufficient amount of the minute odor molecules (gas molecules) to be analyzed contained in the gas, or if it is possible, it takes a long time. Furthermore, once captured, the odor molecules cannot be retained and diffuse and disappear over time, often resulting in problems that prevent high-precision measurement and analysis.

[0007] The object of the present invention is to provide an analytical device that captures odor molecules using an odor cell capable of capturing minute amounts of odor molecules contained in a gas more quickly and in larger quantities than conventional methods, and retaining the captured odor molecules without letting them escape, and then irradiates this odor cell with electromagnetic waves of a specific wavelength to analyze the components of the odor molecules. [Means for solving the problem]

[0008] According to the following disclosure, an analytical apparatus capable of analyzing the components of odor molecules contained in a gas comprises an odor cell having a porous surface coated with a ceramic material for capturing the odor molecules, a gas flow case having an internal space for housing the odor cell, an inlet for introducing the gas containing the odor molecules into the internal space of the gas flow case, an outlet for discharging the gas that has flowed into the internal space from the inlet, a generating unit for generating electromagnetic waves of a specific wavelength, and a unit housing the electromagnetic waves generated by the generating unit in the internal space. The system comprises: a first opening in the gas flow case for irradiating the odor cell; a second opening in the gas flow case for emitting the electromagnetic waves that have been transmitted or reflected after irradiating the odor cell; a first window member that closes the first opening and is permeable to the electromagnetic waves; a second window member that closes the second opening and is permeable to the electromagnetic waves; a detection unit for detecting the electromagnetic waves that have passed through the second window member; and a processing unit that processes the detection signal output from the detection unit to obtain information about the odor molecules.

[0009] Furthermore, according to other disclosures, the electromagnetic waves generated by the generating unit are terahertz waves or infrared rays. The first window member and the second window member are made of a silicon wafer, quartz glass, or polycarbonate (PC).

[0010] Furthermore, according to other disclosures, the ceramic member is composed of zinc oxide or carbon nitride. Alternatively, the ceramic member may be composed of zinc oxide and carbon nitride coated on the zinc oxide. The ceramic member may also be composed of at least one of the following shapes: whisker shape, column shape, or mountain shape.

[0011] Furthermore, according to other disclosures, the system may further include a hydration device that binds water molecules to the odor molecules to hydrate them, and the hydrated odor molecules may be introduced into the gas flow case by this hydration device.

[0012] Furthermore, according to other disclosures, the generating unit generates pulsed terahertz waves, and the processing unit includes an analysis algorithm that obtains information about the components of the odor molecules based on the amplitude and phase values ​​obtained for each frequency by performing a Fourier transform on the detected signal. The processing unit may also include a correction algorithm that corrects for the absorption of the terahertz waves by water molecules. [Effects of the Invention]

[0013] According to the following disclosure, it is possible to provide an analytical device that captures odor molecules using an odor cell capable of capturing odor molecules contained in a gas more quickly and in larger quantities than conventional methods, and retaining the captured odor molecules without letting them escape, and then irradiates this odor cell with electromagnetic waves of a specific wavelength to analyze the components of the odor molecules. [Brief explanation of the drawing]

[0014] [Figure 1] This is an external view of an odor cell according to an embodiment of the present invention. [Figure 2] This is a cross-sectional view of an odor cell according to an embodiment of the present invention. [Figure 3] This is a cross-sectional view showing the types of shapes of the ceramic members of the odor cell according to an embodiment of the present invention. [Figure 4] This is an external view of a gas flow case according to an embodiment of the present invention. [Figure 5] These are external views of the first window member and the second window member of a gas flow case according to an embodiment of the present invention. [Figure 6] This is an external view of a hydration apparatus according to an embodiment of the present invention. [Figure 7] This is a block diagram of an analytical apparatus according to an embodiment of the present invention. [Modes for carrying out the invention]

[0015] (Scent Cell) FIG. 1 is an external view of the odor cell 1 according to a preferred embodiment of the present invention. FIG. 2 is a cross-sectional view of the odor cell 1 in FIG. 1. However, this FIG. 2 is a schematic view in which only the surface of the odor cell 1 and a very small part near the surface are enlarged for easier understanding of the explanation. This odor cell 1 is configured with a porous member 3 having a large number of pores 4 as a base material. The average size of these pores 4 is 50 nm, but it is not limited to this. Depending on the size of the odor molecule to be analyzed and whether or not water molecules adhere around the odor molecule, i.e., whether it is in a so-called hydrated state, it is desirable to select an optimal size each time. Also, this odor cell 1 has a substantially square plate shape with one side being about 5 to 30 mm and a thickness being about 1 to 6 mm, but the size and shape are not limited to this either. It is desirable to select an optimal size according to the size of the cell that can be accommodated in a terahertz spectrometer, an infrared spectrophotometer, etc. Also, the shape of the odor cell 1 may be circular or may be a rectangular parallelepiped with a certain thickness, etc.

[0016] The porous member 3 is preferably porous glass. Generally, about 96% of this porous glass is composed of silicon dioxide (SiO2), has heat resistance close to quartz glass, and is also a material extremely stable against organic solvents. For example, when the average size of the pores 4 of the porous member 3 made of this porous glass is set to 50 nm as described above, the bulk specific gravity is 1.12 g / cc, the porosity is 49.1%, and the internal surface area is 80 m 2 / g, and the total surface area of the pores 4 for capturing the odor molecules 5 is very large. Also, a large number of pores 4 inside the porous member 3 are connected to each other and have a structure that can easily permeate gas as a whole. Currently, generally, a technology has been established that enables the free setting of the pore size in the range of 4 nm to several μm, so it is possible to appropriately select the diameter size of the pores according to the size of the gas molecule to be analyzed.

[0017] In the manufacturing method of such porous glass, a uniform glass is separated into multiple phases by heat treatment, and only the soluble phase is eluted with chemicals, thereby forming numerous pores. Porous glass is being actively researched by various researchers in the fields of microfiltration, ultrafiltration, and separation modes that utilize molecular flow in gas separation. The excellent properties of such porous glass, such as high gas permeability and light transmittance, are particularly advantageous for analyzing the components of odor molecules using terahertz time-domain spectroscopy (THz-TDS) with terahertz gas sensing (THGS) technology, such as the TeraProspector terahertz spectrometer (TeraProspector is a registered trademark of NIPPO Precision Co., Ltd.) from NIPPO Precision Co., Ltd. Furthermore, materials with pores, not just porous glass, act to sieve gas molecules such as odor molecules into large and small molecules according to their effective diameter. That is, small molecules can penetrate deep into the support, while molecules larger than the pores cannot penetrate into the support. Thus, the difference in apparent stationary phase volume due to sample size makes sieving possible.

[0018] Also, as shown in FIGS. 1 and 2, on the surface of the porous member 3 and the inner surface of the pores 4 near the surface, a ceramic member 2 made of zinc oxide (ZnO) is attached by an atmospheric open-type CVD apparatus equipped with an atmospheric open-type chemical vapor deposition method. This ceramic member 2 made of zinc oxide is generally called an oxide film or a ceramic coating, but from a microscopic perspective, it forms a whisker shape called a whisker in this embodiment. More specifically, when manufacturing using the above-described atmospheric open-type CVD apparatus, Zn(C5H7O2)2 (manufactured by High-Purity Chemical Laboratory) with a purity of 99% is prepared, and the vaporization temperature is 120 °C, the N2 carrier gas flow rate is 1.2 L / min, and the substrate temperature is 550 °C, and it can be deposited on a substrate of porous glass, which is the porous member 3, for manufacturing. This atmospheric open-type CVD method has an excellent feature that an oxide film with very few impurities and crystal defects can be manufactured. Furthermore, by appropriately selecting raw materials, crystal growth conditions, etc., a predetermined shape, for example, a width of 100 to 700 nm, an angle of 5 ° to 60 °, a linear density of 1.0 to 5.0×10 4 mm 3 can be determined within the range, and an oxide structure composed of zinc oxide and various other materials can be formed.

[0019] The open-air CVD apparatus described above has excellent features compared to other types of CVD apparatus, including low operating costs and the ability to synthesize oxide thin films relatively easily. Specifically, in the open-air CVD method, the raw material gas is ejected from a nozzle and transported to the target substrate surface. There, the raw material gas generates reaction intermediates through a gas-phase reaction, and while repeatedly adsorption and desorption on the substrate surface, atoms are regularly arranged by surface migration, enabling crystal deposition with few defects. Furthermore, because the raw material is in gaseous form, it is possible to uniformly form a film on the fine irregularities of the target substrate surface, resulting in the secondary effect of exhibiting good step coverage. Another advantage is that, compared to smoothing methods such as mechanical polishing and etching, the possibility of contamination by substances other than the film material is low. For these reasons, the ceramic member 2, such as zinc oxide (ZnO), in the embodiment of the present invention is preferably manufactured using an open-air CVD apparatus.

[0020] Next, the trap structure will be explained using Figure 2. First, a gas containing the odor molecules 5 to be analyzed is blown around the porous member 3, or these odor molecules 5 are carried by Brownian motion towards the porous member 3 or ceramic member 2. As a result, a certain percentage of the odor molecules 5 pass through the micro-protrusions made of the ceramic member 2 and enter the interior of the pores 4, where they are trapped in the trap structure 7 composed of the ceramic member 2 and the pores 4. Once inside this trap structure 7, the odor molecules 5 are hindered by these micro-protrusions, making it difficult for them to escape from the pores 4. Conversely, on the inner surface of the pores 4 that extend further in from the pores 4 near the surface, these obstacles from the ceramic member 2 are less dense and smaller in size than near the surface, making it easier for them to penetrate deeper. As a result, the captured odor molecules 5 move to the pores 4 that extend further in, and are consequently retained within the trap structure 7 for a longer period of time.

[0021] In this way, by modifying the surface of a porous member 3 having numerous pores 4, and the inner surface of the pores 4 near the surface, with ceramic member 2 having whisker-shaped or other fine protrusions of zinc oxide (ZnO) by an open-air CVD method, it is possible to fabricate an odor cell 1 having a unique trap structure 7 capable of capturing odor molecules 5.

[0022] Next, the catching structure will be explained. As shown in Figure 2, when odor molecules 5 fly onto the surface of the odor cell 1, they enter the dense forest of whisker shapes on the ceramic member 2 and are captured. By appropriately setting and manufacturing the shape and linear density of the whisker shapes and other micro-protrusions of the ceramic member 2 according to the size of the odor molecules 5 to be captured, it is possible to directly capture the odor molecules 5 by sandwiching or attaching them to the catching structure 6 made up of the micro-protrusions of the ceramic member 2. Furthermore, if the odor molecules 5 are relatively large, the contact area becomes relatively larger in the shallow depressions (valleys in the mountain shape) made up of micro-protrusions, making it easier for the odor molecules 5 to attach. For this reason, the ceramic member 2 functions similarly even if its shape is (a) whisker shape, (b) column shape, or (c) mountain shape (or mountain range shape), as shown in Figure 3.

[0023] As described above, the trap structure 7 and catching structure 6 that capture these odor molecules 5 aim to obtain a sieving effect based on the Knudsen diffusion theory that occurs within the pores 4, while simultaneously aiming to obtain a surface modification effect based on the linear solvation energy relation (LSER) theory.

[0024] Odor cell 1 was manufactured primarily for the purpose of analyzing the components of captured odor molecules 5 by setting it in a spectrometer or spectrophotometer. In particular, with the aim of making it function effectively in terahertz spectrometers, zinc oxide (ZnO) was selected as the material used for surface modification, focusing on the transmittance of terahertz waves. Furthermore, by arranging these zinc oxide ceramics in a whisker shape, we proposed odor cell 1 with its unique trap structure 7 and catching structure 6. While terahertz waves or infrared light are preferable for the electromagnetic waves of a spectrometer used to analyze the components of odor molecules 5, this does not exclude spectrophotometers that use ultraviolet or visible light. The wavelengths of electromagnetic waves used by spectrometers and spectrophotometers that can utilize this odor cell 1 are 200 nm to 2000 nm, meaning that infrared, visible, and ultraviolet light can also be targeted.

[0025] Furthermore, compared to conventional simple porous materials or combinations of multiple porous layers with different central pore diameters, such as the porous layers 121-125 in Patent Document 2, the above-described embodiment, despite having a relatively simple structure, is capable of capturing more odor molecules 5 in a shorter time than conventional methods, through the trap structure 7 within the pores 4 and the direct catching structure 6 by the ceramic member 2. Moreover, it has the excellent effect of being able to retain the captured odor molecules 5 for a longer period of time than conventional methods. This improves responsiveness by shortening the time required for component analysis, structural analysis, and quantification of odor molecules 5 using spectroscopic analyzers and spectrophotometers that utilize terahertz waves or infrared light, and also has the excellent effect of improving the sensitivity of the analysis from the conventional ppm level to the ppb level.

[0026] Furthermore, the material of the ceramic member 2 in the above embodiment may be carbon nitride (CNx) instead of zinc oxide (ZnO). In this case, the ceramic member 2 can be manufactured by depositing carbon nitride on the porous member 3 using ECR plasma CVD. The shape can also be any of the shapes shown in Figure 3, similar to zinc oxide: (a) whisker shape, (b) cylindrical shape, or (c) mountain shape (mountain range shape).

[0027] Furthermore, it is also possible to construct the ceramic member 2 by first depositing zinc oxide (ZnO) onto the porous member 3 using open-air CVD, and then forming a carbon nitride (CNx) film using ECR plasma CVD. In this case, the efficiency of capturing odor molecules 5 is further improved, and because the carbon nitride film is very hard, it also functions as a protective film that prevents deterioration such as wear and oxidation of the zinc oxide. Therefore, this has the effect of improving the durability and extending the lifespan of the odor cell 1.

[0028] As described above, porous glass made of glass is preferred as the porous member 3, but the material is not limited to this, and any material that is transparent to electromagnetic waves used for analysis, such as terahertz waves and infrared light, can be used as a substitute. For example, zeolite having regular channels (tubular pores) and cavities, mesoporous silica (MS) having a structure in which pores are regularly aligned, and porous coordination polymers (PCP) / metal-organic frameworks (MOF) can also be applied. Although porous materials alone have some function in capturing odor molecules, by coating the surface of these porous materials and the inner surface of the pores near the surface with the ceramic member of the above embodiment, it becomes possible to manufacture an odor cell that captures odor molecules more efficiently.

[0029] According to the IUPAC (International Union of Pure and Applied Chemistry) definition, porous materials are classified into three categories based on the diameter of their pores: (1) micropores if the pore diameter is 2 nm or less, (2) mesopores if the pore diameter is between 2 nm and 50 nm, and (3) macropores if the pore diameter is 50 nm or larger. For example, the above-mentioned PCP has a pore diameter of approximately 0.4 nm to 6 nm, offering a wide variety of options in the micropore to mesopore range, and it is possible to select any pore size from this range and apply it to the porous material 3 of this embodiment. As such, there are many types of porous materials that are transparent to electromagnetic waves such as terahertz waves and infrared light, and therefore, it is possible to freely select the optimal material by comprehensively considering factors such as the size and chemical properties of the odor molecules to be analyzed, the operating environment of the spectrometer or spectrophotometer, the pore size, processability, and cost.

[0030] (Gas flow case) Figure 4 is an external view of the gas flow case 10 that houses the odor cell 1 described above. The gas flow case 10 has an internal space 13 in the center of the main body for housing the odor cell 1, and is a device for exposing the odor cell 1 to a gas containing the odor molecules 5 to be analyzed. As a result, the odor molecules 5 are captured by the odor cell 1 and become ready for analysis. If, without the odor cell 1, the internal space 13 were simply filled with a gas containing the odor molecules 5 to be analyzed, and electromagnetic waves were irradiated to analyze the odor molecules 5, then, for example, if the concentration of odor molecules 5 in the gas is at the ppm or ppb level, the concentration would be too dilute to detect changes in the transmitted electromagnetic waves, and detection would be virtually impossible with the sensitivity of current detectors. Therefore, in this embodiment, an odor cell 1 capable of efficiently capturing odor molecules 5 is housed in the internal space 13 of the gas flow case 10, and a gas containing odor molecules 5 is introduced and exposed to it. This allows odor molecules 5 to be captured in large quantities in the odor cell 1, and the concentration of odor molecules 5 per unit area in the odor cell 1, which is irradiated with electromagnetic waves, becomes extremely high compared to the concentration in the gas, making it possible to analyze odor molecules 5 using electromagnetic waves.

[0031] In this embodiment, stainless steel is used as the material for the gas flow case 10, taking into consideration robustness, corrosion resistance, processability, and cost. When the electromagnetic waves used for analysis are terahertz waves, infrared light, visible light, or ultraviolet light, stainless steel does not transmit these materials. Therefore, it is necessary to provide a first opening 11 in the gas flow case 10 to irradiate the odor cell 1 housed in the internal space 13 with electromagnetic waves, and a second opening to emit the electromagnetic waves that have been transmitted or reflected from the odor cell 1.

[0032] Furthermore, the periphery of the first opening 11 and the second opening are provided with a first stepped portion 12 and a second stepped portion, respectively, for mounting a disc-shaped window member 20 as shown in Figure 5. The window member 20, which is mounted on at least one of the first stepped portion 12 and the second stepped portion, is detachably mounted for the purpose of replacing the odor cell 1 housed in the internal space 13 or for cleaning the internal space 13. However, it is preferable that a sealing member such as an O-ring is placed between the first stepped portion 11 and the second stepped portion and the window member 20 mounted thereon to prevent gas leakage from the gas flow case 10. Furthermore, an inlet passage 14 for introducing gas containing odor molecules 5 into the internal space 13 of the gas flow case 10 and an outlet passage 15 for discharging the gas that has entered the internal space 13 are connected.

[0033] (Window components) Figure 5 shows the external view of the first and second window members 20. The material of these window members 20 needs to be transparent to electromagnetic waves of a specific wavelength used for analysis. In the embodiments disclosed herein, the electromagnetic waves used for analysis are terahertz waves or infrared rays, so a silicon wafer is suitable as a material that is transparent to these waves and also has excellent weather resistance, processability, and robustness. A high-purity silicon wafer is particularly preferable. <111> The silicon wafer, when polished to standard optical polishing (infrared spectroscopy grade), has high resistivity (preferably 1,000 Ω·cm or higher) and contains almost no free electrons or holes, so the energy of terahertz waves is not absorbed by free electrons or holes. Therefore, the irradiated electromagnetic waves can be transmitted through this window member without significant attenuation. Furthermore, this silicon wafer has high transmittance for infrared rays in the mid-infrared region with wavelengths of 1.1 to 7 μm, but conversely, its transmittance decreases significantly in the near-infrared region below 1.1 μm and the far-infrared region above 7 μm. Therefore, this function can be used as a filter to create an analytical device that limits the electromagnetic waves irradiated from the generation unit to only terahertz waves or mid-infrared rays (especially wavelengths of 1.1 to 7 μm). In addition, although such a high-purity silicon wafer has high transmittance for terahertz waves and mid-infrared rays, it is not 100% and some attenuation is observed. Therefore, it is desirable to make it as thin as possible, but silicon wafers are very hard (Vickers hardness of approximately 1150 kgf / mm²). 2 ) Also, since thin materials are prone to cracking from impact, it is preferable to make them a certain thickness, for example, about 1 mm or more.

[0034] It is also possible to use quartz glass for the window component 20. Generally, quartz glass is said to have a transmittance of 50-90% in the range of 0.1-1 THz. Naturally, it also transmits visible light, making it possible to visually inspect the internal space 13. However, while it has high transmittance to near-infrared light, its transmittance decreases in mid-infrared light with wavelengths of 3 μm or more, and it almost completely loses transmittance to wavelengths exceeding approximately 10 μm. Furthermore, although quartz glass is basically amorphous, there is a problem in that the transmittance of terahertz waves appears directional in each individual piece, which is thought to be caused by differences in manufacturing methods. Therefore, it is necessary to select quartz glass without directional transmittance and apply it to the window component. Also, because it is hard and brittle, it is preferable to use a certain thickness or more, for example, 5 mm or more, when using it for the window component 20.

[0035] Furthermore, polycarbonate (PC) can also be used for the window component 20. It has good transparency to terahertz waves and excellent mechanical strength and impact resistance. However, since it is basically a resin material, it has problems in terms of weather resistance compared to silicon wafers and quartz glass. Generally, additives are often used to improve this weather resistance (UV resistance, moisture resistance, etc.), but since regulations on the use of additives are becoming stricter worldwide year by year, it is desirable to avoid using additives as much as possible. In this regard, although it will increase costs and effort, it is possible to avoid this problem by replacing the component regularly.

[0036] Furthermore, since polycarbonate (PC) is transparent even in visible light, it becomes possible to visually inspect the internal space 13. However, its refractive index for terahertz waves is generally said to be about 1.6, so some reflection is a concern. In addition, while it has sufficient transparency to near-infrared rays (0.7~3 μm), its transparency to mid-infrared rays (3~30 μm) and far-infrared rays (30 μm or more) is significantly reduced. Considering all of the above, in the disclosed embodiment, silicon wafers are considered more suitable as window members compared to quartz glass and polycarbonate (PC).

[0037] (hydration device) Figure 6 is an external view of the hydration apparatus 30, which is used to hydrate odor molecules 5 by attaching water molecules to them. While it is certainly possible to introduce the odor molecules 5 directly into the gas flow case 10 and analyze them, it is more efficient to hydrate them using this hydration apparatus 30 before capturing them in the odor cell 1 in order to capture more odor molecules 5. Furthermore, the hydrated state allows the odor molecules 5 to remain in the odor cell 1 for a longer period of time. In other words, it is more preferable for the odor molecules 5 to be in a hydrated state in the analytical apparatus 50 of this embodiment.

[0038] For example, if analyzing odor molecules rising from tap water or from the ground after rain, the odor molecules are likely to be already hydrated, so the gas can be introduced directly into the gas flow case 10 for analysis without passing through this hydration device. The analytical device 50 in this embodiment is particularly suitable for checking the odor of water in water treatment plants and identifying the substances causing unpleasant odors.

[0039] Next, we will explain the mechanism by which this hydration device 30 hydrates the odor molecules 5. The gas containing the odor molecules 5 to be analyzed is drawn into the water 34 in the sealed bottle 31 via the inlet pipe 32. A porous bubble section 35 for generating fine bubbles is connected to the tip of this inlet pipe 32, and the gas that flows in here is released into the water 34 as fine bubbles from this bubble section 35. These released bubbles rise towards the water surface in the water 34. As the odor molecules 5 move from the water to the water surface as fine bubbles in this way, they become hydrated, with water molecules attaching to them. The gas containing these hydrated odor molecules 5 is then introduced into the internal space 13 via the inlet passage 14 of the gas flow case 10 described above, via the discharge pipe 33. However, some odor molecules will be incorporated into the water 34 of the hydration apparatus 30, but this will not particularly hinder the analysis as long as a sufficient amount of gas is supplied to permeate the hydration apparatus 30.

[0040] In addition, when performing spectroscopic analysis using terahertz waves, it has been common practice to dry the analyte as much as possible beforehand using, for example, silica gel, because water molecules have a strong absorption property of terahertz waves. However, in the embodiment of the present invention, by providing an algorithm in the processing unit 44 that corrects for the effect of water molecules, it is possible to analyze even hydrated odor molecules 5. In fact, because the odor molecules 5 are hydrated, it becomes possible for the odor cell 1 to capture odor molecules 5 more efficiently in a shorter time and in a larger quantity.

[0041] (Analyzer) Figure 7 is a functional block diagram showing the main functions of the analyzer 50. The flow of the analysis operation of the analyzer 50 will be explained using Figure 7. First, with the odor cell 1 set in the internal space 13 of the gas flow case 10, and before introducing the gas containing the odor molecules 5 to be analyzed, the generator 40 outputs electromagnetic waves of a specific wavelength used for analysis, which are irradiated as incident waves 41 toward the window member 20 of the first opening 11 of the gas flow case 10. Then, the electromagnetic waves are irradiated as outgoing waves 42 toward the detection unit 43 from the window member 20 of the second opening 12. The detection unit 43 detects the outgoing waves 42 and outputs a detection signal. This detection signal is input to the processing unit 44 and processed, and is first recorded as information of electromagnetic waves in a state where there are no odor molecules 5.

[0042] Next, a gas containing the odor molecules 5 to be analyzed is introduced from the inlet passage 14. At this time, the gas may be blown in under pressure from the upstream side of the inlet passage 14, but it is more preferable to draw it in from the downstream side of the discharge passage 15 to prevent contamination by the pressurizing device. It is also more preferable to introduce the gas that has passed through the hydration device 30 described above. After the introduction of the predetermined gas, pulsed electromagnetic waves of a specific wavelength used for analysis are output again from the generation unit 40 and irradiated as an incident wave 41 toward the window member 20 of the first opening 11 of the gas flow case 10. Then, the electromagnetic waves are irradiated as an outgoing wave 42 toward the detection unit 43 from the window member 20 of the second opening 12. The detection unit 43 detects the outgoing wave 42 and outputs a detection signal. This detection signal is input to the processing unit 44 and processed, and recorded as information on the state of the electromagnetic waves including the changes caused by the odor molecules 5.

[0043] (processing) The processing in the processing unit 44 can utilize so-called terahertz time-domain spectroscopy (THz-TDS) if the electromagnetic wave used is a pulsed terahertz wave. This involves performing a Fourier transform on the detection signal described above to obtain amplitude and phase values ​​for each frequency. Generally, terahertz time-domain spectroscopy, which is used to analyze the internal structure, carrier dynamics, and crystal structure of materials, has rarely been used to analyze trace amounts of odor molecules at ppm or ppb levels contained in gases.

[0044] By comparing the values ​​before and after introducing the odor molecule 5 to be analyzed, it can be determined that the changed portion is related to the odor molecule 5. This makes it possible to analyze the components of the odor molecule 5 introduced into the gas flow case 10. Furthermore, if the odor molecule 5 is in a hydrated state after passing through the hydration device 30, or if it is an odor molecule that is originally in a hydrated state even without passing through the hydration device 30 (for example, an odor molecule rising from water in a water treatment plant), it is preferable to configure the system to perform correction using an algorithm that corrects for the absorption of terahertz waves by water molecules.

[0045] Furthermore, if the electromagnetic waves used are in the mid-infrared region, infrared spectroscopy (IR spectroscopy) can be used. Infrared spectroscopy is an analytical technique that involves irradiating a substance with infrared light, causing absorption at wavelengths corresponding to the vibrations and rotations of specific molecules. By examining the vibrational modes of these molecules, it is possible to identify chemical bonds and molecular structures. However, it has not been used much in the past for the analysis of odor molecules.

[0046] Regardless of which spectroscopic method is used to analyze odor molecules in the processing unit 44, the amount of odor molecules present in the gas is almost always at the ppm or ppb level, and since they are extremely dilute, it was impossible to analyze them in their original state. In the embodiment of the present invention, by using an odor cell 1 that can capture a large amount of these dilute odor molecules in a shorter time than conventional methods, and by concentrating the odor molecules in a small area of ​​the odor cell 1, analysis becomes possible using any spectroscopic method. [Explanation of symbols]

[0047] 1…Scent cell 2…Ceramic components 3…Porous material 4…Pores 5… Odor molecules 6…Catching structure 7…Trap structure 10…Gas flow case 11…First opening 12…Second opening 13…Interior space 14...Inflow channel 15...Discharge path 20... Window components 30…Hydration device 34…Water 35...bubble area 41...Incoming wave 42...Emitted Waves 50…Analyzer

Claims

1. In an analytical instrument capable of analyzing the components of odor molecules contained in a gas, A porous member whose surface is coated with a ceramic material, comprising an odor cell that captures odor molecules, A gas flow case having an internal space for housing this odor cell, The gas flow case has an inlet passage for introducing the gas containing the odor molecules into the internal space, A discharge passage for discharging the gas that has flowed into the internal space from this inlet passage, A generating unit that generates electromagnetic waves of a specific wavelength, A first opening is made in the gas flow case to irradiate the electromagnetic waves generated in this generating unit onto the odor cell housed in the internal space, A second opening is provided in the gas flow case to emit the electromagnetic waves that have been transmitted or reflected after being irradiated onto the odor cell, A first window member that closes the first opening and allows electromagnetic waves to pass through, A second window member that closes the second opening and allows electromagnetic waves to pass through, A detection unit for detecting the electromagnetic waves that have passed through this second window member, A processing unit that processes the detection signal output from this detection unit to obtain information about the odor molecules, An analytical device equipped with the following features.

2. The analytical apparatus according to claim 1, characterized in that the electromagnetic waves generated by the generating unit are terahertz waves or infrared rays.

3. The analytical apparatus according to claim 1, characterized in that the first window member and the second window member are made of a silicon wafer, quartz glass, or polycarbonate (PC).

4. The analytical apparatus according to claim 1, characterized in that the ceramic member is composed of zinc oxide or carbon nitride.

5. The analytical apparatus according to claim 1, characterized in that the ceramic member is composed of zinc oxide and carbon nitride coated on the zinc oxide.

6. The analytical apparatus according to claim 4 or 5, wherein the ceramic member is composed of at least one of the following shapes: whisker shape, column shape, or mountain shape.

7. The analytical apparatus according to claim 1, further comprising a hydration device that binds water molecules to the odor molecules to create a hydrated state, and characterized in that the hydrated odor molecules are introduced into the gas flow case by the hydration device.

8. The analytical apparatus according to claim 1, characterized in that the generating unit generates pulsed terahertz waves, and the processing unit performs a Fourier transform on the detected signal and includes an analysis algorithm that obtains information about the components of the odor molecules based on the amplitude and phase values ​​obtained for each frequency.

9. The analytical apparatus according to claim 8, characterized in that the processing unit includes a correction algorithm for correcting the absorption of terahertz waves by water molecules.

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