JP2009210305A - Gas quantitative analysis method and gas quantitative analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine abundance of a plurality of component molecules included in a sample, accurately in real time based on gas obtained from the sample, by utilizing ionization processing causing no cleavage. <P>SOLUTION: This gas quantitative analysis method has: a thermogravimetric measurement step S32 for determining the weight of gas obtained from the sample in which the abundance of the target molecules is unknown; area intensity measurement steps S33-S40 for ionizing the gas by soft ionization treatment to determine mass analysis data I (m/z, t), determining a mass chromatogram based on the mass analysis data, and determining the area intensity of a peak waveform in the mass chromatogram; and a quantitative operation step S40 for determining the abundance of the target molecules based on the weight of the gas determined in the thermogravimetric measurement step and the area intensity determined in the area intensity measurement steps. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gas quantitative analysis method and a gas quantitative analysis apparatus that perform quantitative analysis, which is analysis for obtaining the abundance of one or a plurality of molecules contained in a sample.

  Gas analysis methods include qualitative analysis and quantitative analysis. The qualitative analysis is an analysis for determining the type of molecule contained in the substance to be measured. The type of molecule can be estimated based on information on molecular weight and molecular structure. The quantitative analysis is an analysis for determining the abundance of molecules contained in the substance to be measured, for example, the amount of components, content, concentration, and the like.

  Conventionally, it is known to perform quantitative analysis by mass spectrometry. In this quantitative analysis, first, a mass chromatogram (horizontal axis = time or temperature, vertical axis = ionic strength) is obtained by electron impact ionization (hereinafter referred to as EI) treatment for molecules whose abundance is known. Then, the area intensity of the peak waveform of the mass chromatogram is obtained, and a calibration curve is created based on the relationship between the area intensity and the known abundance. Next, a mass chromatogram is obtained by EI treatment for a sample in which the abundance of component molecules is unknown, the area intensity of the peak waveform is further obtained, and the obtained area intensity is applied to the above calibration curve. Determine the abundance.

  However, in this conventional quantitative analysis, since ionization of the sample is performed by EI treatment, there are the following problems. In other words, in the EI treatment, the molecule is ionized by colliding electrons with the molecule, so that the fragment corresponding to the parent molecule for which the abundance is to be obtained (parent ion) is generated by fragmentation of the parent molecule. Ions are observed. Although this fragment ion gives an important factor in estimating the structure of the molecule, the presence of this fragment ion weakens the strength of the parent molecular ion, or the parent ion of one molecule has another molecule. In many cases, accurate information on the parent molecular ion cannot be obtained. For this reason, the mass chromatogram obtained based on the EI treatment does not accurately reflect the ionic strength of the component molecules, so a calibration curve cannot be accurately created, and the parent ionic strength of the unknown sample is also accurate. It was not possible to measure.

  As a quantitative analysis based on mass spectrometry, an analysis using GC-MS (Gas Chromatograph-Mass spectrometer) is also known. In this device, the sample gas is passed through a gas chromatograph, which is a separation device, a pure single component that has passed is detected by a mass spectrometer, a mass chromatogram is obtained, and the area intensity of the peak waveform of this mass chromatogram is calculated. Then, the abundance of a single component is obtained from the calculated intensity according to a calibration curve.

  According to GC-MS, a plurality of single-component molecules are sequentially carried into the ionization region by EI treatment and ionization is performed on each, so that the parent ion of the molecule influences the fragment ions of other molecules. Therefore, accurate quantitative analysis can be performed as compared with the quantitative analysis based only on the above EI processing. However, in GC-MS, since the gas generated from the sample must be separated over time by GC, there is a drawback that the gas generated from the sample cannot be analyzed in real time.

  Here, real-time refers to a gas that is emitted from a gas source such as a sample, etc., and whose components, component ratio (concentration), etc. change over time, either directly or simultaneously or immediately. Analyzing without collecting, analyzing without adding a secondary treatment, or analyzing a gas in a state where the component content and the component ratio as generated are maintained.

  By the way, one of the inventors of the present application, in Non-Patent Document 1, performs TG (Thermogravimetry: thermogravimetry) measurement and MS (Mass Spectrometry: mass spectrometry) measurement on a standard sample at the same time. Proposed a quantification method in which a calibration curve representing the relationship between the molecular ionic strength and the area value is created in advance, and the ionic strength of the molecule whose abundance is unknown is measured to determine the abundance of the molecule from the calibration curve. did.

  On the other hand, chemical ionization (CI), photoionization (PI), and the like have recently been proposed as ionization capable of suppressing fragment ions, which are disadvantages of EI. These ionizations are sometimes called soft ionizations because they can suppress fragment ions. According to this soft ionization, only the parent molecular ion of the molecule can be selectively ionized and observed, so that each component molecule contained in the mixed gas can be identified in real time for each molecular ion.

  The present inventors have already proposed a mass spectrometer having both functions of EI processing and soft ionization processing (see, for example, Patent Document 1). Japanese Patent Application Laid-Open No. H10-228667 describes in detail a method for performing EI processing and soft ionization processing independently and simultaneously performing them. In addition to the mass analysis based on these ionization treatments, it is briefly mentioned that TG measurement is simultaneously performed. However, there is no specific teaching on how to associate TG measurements with mass spectrometry.

Material Integration Vol. 15, no. 6, 60-63 pages International Publication WO2007 / 108211 Pamphlet (pages 20-48, FIG. 1)

  In the TG-MS measurement disclosed in Non-Patent Document 1, molecular ionization was performed using EI. This is not necessarily clearly shown in Non-Patent Document 1, but at that time, EI was common in terms of molecular ionization, and PI and CI were not normally used. However, since ionization by EI generates fragment ions by cleavage as described above, if a sample includes a plurality of component molecules, interaction occurs between these molecules during ion generation, It is difficult to determine the abundance of component molecules. That is, the technique of Non-Patent Document 1 is effective when the sample is a single component, but accurate quantitative analysis cannot be performed when the sample has a plurality of molecules as components. This is described in the “Summary” column of Non-Patent Document 1.

  Patent Document 1 suggests that gas analysis is performed by combining mass analysis using both EI and soft ionization and TG measurement. However, there is no mention of a specific method for utilizing this gas analysis.

  The inventors of the present invention have made extensive efforts to improve analysis accuracy when quantitatively analyzing in real time a gas obtained from a sample containing a plurality of component molecules. As a result, mass spectrometry is performed using soft ionization, which is ionization without cleavage, and a mass chromatogram is obtained. If quantitative analysis is performed based on the mass chromatogram, very accurate quantitative analysis can be performed in a short time. I thought I could do it.

  Therefore, the present invention makes it possible to accurately determine the abundance of a plurality of component molecules contained in a sample in real time based on the gas obtained from the sample by utilizing an ionization process that does not involve cleavage. The purpose is to.

  The first gas quantitative analysis method according to the present invention includes (1) mass spectrometry data I (m / z, t) obtained by ionizing a gas obtained from a standard sample in which the abundance of the target molecule is known by a soft ionization process. A calibration curve creating step for obtaining a mass chromatogram based on the mass spectrometry data, obtaining an area intensity of the peak waveform of the mass chromatogram, and creating a calibration curve based on the abundance and the area intensity And (2) ionizing a gas obtained from a sample in which the abundance of the target molecule is unknown by soft ionization to obtain mass spectrometry data I (m / z, t), and based on the mass spectrometry data, An unknown sample measurement step for obtaining a mass chromatogram of a molecule and obtaining an area intensity of a peak waveform of the mass chromatogram, and (3) the calibration curve obtained in the calibration curve creation step based on the calibration curve Characterized in that the integrated intensity obtained by the known sample measurement step and a step of obtaining the abundance of the target molecule.

  According to the present invention, mass spectrometry data is measured for ions obtained by soft ionization treatment, a mass chromatogram is created based on the mass analysis data, a calibration curve is created based on the mass chromatogram, Quantification is performed using the calibration curve. Since soft ionization is an ionization that generates only the parent ion without generating fragment ions, the created mass chromatogram accurately reflects the ionic strength of the component molecules, and thus was finally determined. The quantitative analysis results are very accurate and reliable compared to the analysis using EI accompanied by generation of fragment ions.

  In the present invention, the component molecules in the sample are not trapped and separated as in GC-MS, and then mass spectrometry is performed, but the parent of each molecule is obtained only by one measurement when the measurement gas is generated. Since only the ions are accurately separated individually by the soft ionization process and the quantitative analysis is performed on each molecule, the quantitative analysis can be performed in real time. That is, according to the quantitative analysis of this embodiment, a very accurate and highly reliable quantitative analysis can be performed in real time.

  The analysis method according to the present invention is effective for quantifying the abundance of molecules contained in a solid substance or liquid substance. It is also effective for quantifying the abundance of molecules contained in exhaust gas discharged from automobiles and other vehicles.

  The second gas quantitative analysis method according to the present invention includes (1) a thermogravimetric measurement step for determining the weight of a gas obtained from a sample whose target molecule is unknown, and (2) a soft ionization treatment of the gas. To obtain mass spectrometry data I (m / z, t), obtain a mass chromatogram based on the mass spectrometry data, and obtain an area intensity of a peak waveform of the mass chromatogram, 3) It has a quantitative calculation step for obtaining the abundance of the target molecule based on the weight of the gas obtained in the thermogravimetric measurement step and the area strength obtained in the area strength measurement step.

  According to the method of the present invention, mass spectrometry data is measured for ions obtained by soft ionization, for example, PI, a mass chromatogram (see FIG. 9) is created based on the mass analysis data, and based on the mass chromatogram. Quantify the constituent molecules. Since soft ionization is an ionization that generates only the parent ion without generating fragment ions, the created mass chromatogram accurately reflects the ionic strength of the component molecules, and thus was finally determined. The quantitative analysis results are very accurate and reliable compared to the analysis using EI accompanied by generation of fragment ions.

  Also, in the method of the present invention, the component molecules are not trapped and separated once as in GC-MS, and then mass spectrometry is performed, but only the parent ions of the component molecules are obtained only by one measurement when the measurement gas is generated. Since it was decided to carry out quantitative analysis on the component molecules by separating them individually by soft ionization, quantitative analysis can be performed in real time. That is, according to the quantitative analysis of this embodiment, a very accurate and highly reliable quantitative analysis can be performed in real time.

  Furthermore, in the method of the present invention, quantitative analysis can be performed without using a calibration curve. For this reason, it is possible to perform the quantitative analysis very easily and in a short time as compared with the quantitative analysis using the calibration curve.

  In the gas quantitative analysis method according to the present invention, the soft ionization process is preferably a photoionization process performed using light having energy that does not generate fragment ions with respect to the target molecule. Examples of such soft ionization treatment include CI and PI.

  In the first gas quantitative analysis method according to the present invention, the ionization efficiency of the target molecule is obtained from the slope of the calibration curve obtained in the calibration curve creation step, and the area intensity of the peak waveform of the mass chromatogram is further determined. It is desirable to have a step of correcting with efficiency.

  The second gas quantitative analysis method according to the present invention obtains mass spectrometry data I (m / z, t) by ionizing a gas obtained from a standard sample in which the abundance of the target molecule is known by a soft ionization process. Obtaining a mass chromatogram based on the mass spectrometry data, obtaining an area intensity of a peak waveform of the mass chromatogram, creating an abundance-area intensity diagram based on the abundance and the area intensity, It is desirable to further include the step of obtaining the ionization efficiency of the target molecule from the slope of the abundance-area intensity diagram and correcting the area intensity of the peak waveform of the mass chromatogram with the ionization efficiency.

  The above “abundance-area intensity diagram” is substantially the same as the “calibration curve”, but the second gas quantitative analysis method performs the quantification without using the calibration curve. The word “strength diagram” is used.

  In the gas quantitative analysis method that uses the calibration curve and the abundance-area intensity diagram to determine the ionization efficiency, the standard sample used to create the calibration curve and the abundance-area intensity diagram is volatile at room temperature. In the case of a sample, it is desirable to store the standard sample in a container with a pinhole.

  The gas quantitative analysis method according to the present invention preferably further includes a qualitative analysis step of obtaining a mass spectrum from the mass analysis data I (m / z, t) and identifying the type of the molecule based on the mass spectrum. .

  Further, in the qualitative analysis step, the gas is ionized by an electron impact ionization process to obtain a first mass spectrum, the gas is ionized by a soft ionization process to obtain a second mass spectrum, and a component from the second mass spectrum is obtained. It is desirable to obtain the molecular m / z value, narrow down the output data of the reference database based on the obtained m / z value, and identify the component molecules by comparing the narrowed output data with the first mass spectrum. .

  Next, a first gas quantitative analysis apparatus according to the present invention includes (A) mass analysis means for ionizing a gas by a soft ionization process to generate mass analysis data, and (B) a mass based on the mass analysis data. An area intensity calculating means for generating a chromatogram and calculating the area intensity of the mass chromatogram; (C) an input means for inputting the abundance of molecular components; (D) the mass analyzing means; and the area intensity calculating means. And (E) the control means has a calibration curve creation control mode and a quantitative analysis control mode, and (F) the control means has (a) a control means for controlling the operation of the input means. ) In the calibration curve creation control mode, (a) the data input to the input means is stored in the storage means as the abundance of the molecular component contained in the standard sample, (b) the stored abundance and the surface A calibration curve is calculated based on the area intensity calculated by the intensity calculation means and stored in the storage means. (B) In the quantitative analysis control mode, (a) mass analysis data is generated by the mass analysis means, (A) The area intensity of the mass chromatogram is calculated based on the mass analysis data by the area intensity calculating means, and (c) stored in the storage means in the calibration curve creation control mode based on the calculated area intensity. The abundance is calculated according to the calibration curve.

  Next, the second gas quantitative analysis apparatus according to the present invention includes (1) thermogravimetric measurement means for obtaining the weight of the gas obtained from the sample, and (2) mass spectrometry data obtained by ionizing the gas by a soft ionization process. (3) Mass spectrum generating means for generating a mass spectrum based on the mass analysis data, (4) Display means for displaying the mass spectrum as an image, and (5) Mass spectrometry. An area intensity calculating means for generating a mass chromatogram based on the data and calculating the area intensity of the peak waveform of the mass chromatogram for each peak waveform; and (6) the weight of the gas determined by the thermogravimetric measuring means; Quantitative calculation means for calculating the abundance of the component corresponding to the peak waveform based on the area intensity for each peak waveform calculated by the area intensity calculating means And having a, the.

(First embodiment)
Hereinafter, a gas quantitative analysis method and apparatus according to the present invention will be described based on embodiments. Of course, the present invention is not limited to this embodiment.

  FIG. 1 shows an embodiment of a gas quantitative analysis apparatus for carrying out a gas quantitative analysis method according to the present invention. This quantitative gas analyzer 1A includes a soft ionization mass spectrometer 2, an image display device 3, a printer 4, an input device 6, and a control device 7A. The image display device 3 is configured by a flat display such as a liquid crystal display device. The printer 4 is constituted by, for example, an electrostatic transfer printer. The input device 6 includes a mouse, a keyboard, and the like.

  The gas G to be quantified is supplied to a predetermined input port of the soft ionization mass spectrometer 2. The gas G is a gas containing one or a plurality of molecular components whose abundance (that is, component amount, content) is unknown. The gas G is, for example, gas generated from a heated solid sample, exhaust gas discharged from an automobile, or the like. This gas quantitative analysis apparatus specifies (that is, determines) the abundance of molecules contained in the gas G.

  When this apparatus is used for generated gas analysis, a sample processing unit (not shown) is provided in front of the soft ionization mass spectrometer 2, and a solid sample or a liquid sample is provided at a predetermined sample position in the sample processing unit. Is placed. A temperature regulator is provided around the sample position, and this temperature regulator has a heater and, if necessary, a cooler. When the temperature of the solid sample is raised according to a predetermined program and lowered as necessary, a gas is generated from the sample at an appropriate temperature according to the characteristics of the sample, and one or more molecules contained in the gas Is quantified by the gas quantitative analyzer of this embodiment. Further, when this apparatus is used for quantification of molecules in the exhaust gas, the exhaust gas is directly supplied to the SI mass spectrometer 2.

  For example, as shown in FIG. 2, the soft ionization mass spectrometer 2 includes a soft ionization device 9 that receives the quantified gas G, an ion separation device 11, an ion intensity detection device 12, and MS control that controls the operations thereof. Device 13. The soft ionization apparatus 9 is an apparatus that ionizes molecules constituting the introduced gas, and in particular, ionizes only component molecules without causing ion cleavage.

  The soft ionization device 9 is configured using, for example, a photo-ionization device, a chemical ionization device, or the like. The photoionization device and the chemical ionization device may be referred to as a PI device and a CI device, respectively. The PI apparatus is an apparatus that irradiates light to molecules and ionizes the molecules. As the wavelength of light, ultraviolet light, vacuum ultraviolet light, soft X-ray, etc. are used in order from the longest. Laser light can also be used. The CI apparatus ionizes component molecules by causing ionized molecules of reaction gas (sometimes called reagent gas) to collide with the component molecules of the gas. The ionization of reaction gas molecules is performed according to the principle of EI (Electro Impact Ionization). In both PI and CI treatments, no cleavage occurs upon ionization of the molecules, and therefore only molecular weight related ions can be obtained.

  The ion separation device 11 separates the generated ions according to m / z values (mass-to-charge ratio) and supplies the ions to the ion intensity detection device 12. For example, ions are converted into m / z using an electric field or a magnetic field. Separate by value. As a device using an electric field, a quadrupole ion separation device that separates ions according to m / z values by arranging four rod-shaped electrodes in parallel with each other and controlling the voltage applied to them can be used.

  The ion intensity detection device 12 is configured using an electron multiplier that emits electrons when hit by ions. The ion intensity I (m / z) for each m / z value is output to the output terminal of the ion intensity detector 12. In addition, since the scanning of the m / z value by the ion separator 11 is performed in a predetermined step time, the ion intensity I (m / z) for each m / z value is expressed as an amount with the time (t) as a variable. In this case, it can be expressed as I (m / z, t).

  The control device 7A in FIG. 1 is configured using a computer. Specifically, the control device 7A includes a CPU (Central Processing Unit) 14 and a memory 16. As is well known, the CPU 14 performs calculations for realizing various functions by a computer and controls operations of various devices in the computer. The memory 16 is a storage medium for storing various information in a predetermined processing format, and is configured by a mechanical memory or a semiconductor memory.

  The memory 16 also includes a RAM (Random Access Memory) and a ROM (Read Only Memory) which are internal memories of the computer. The processing performed by the CPU 14 may be performed using the RAM as a temporary storage area. Inside the memory 16, there are provided program software for executing quantitative analysis described later, a file area for storing various data, and a memory area for storing various data.

  Hereinafter, a gas quantitative analysis method performed by the gas quantitative analysis apparatus 1A having the above-described configuration will be described with reference to a flowchart shown in FIG. In this embodiment, a sample containing various molecules can be measured. In the following description, benzene (m / z = 78), toluene (m / z = 92) will be described for easy understanding. ) And xylene (m / z = 106) as a measurement target, the content of each component molecule contained in the substance, that is, the amount of component, that is, the abundance is specified. To do, ie to quantify.

  The measurer does not clearly recognize that the substance contains benzene, toluene, or xylene, but there is some recognition that these molecules may be included. To do. In this embodiment, soft ionization is performed by PI (photoionization) processing using vacuum ultraviolet light. In the drawings referred to in the following description, benzene may be represented by “B”, toluene may be represented by “T”, and xylene may be represented by “X”.

  In the gas quantitative analysis method of the present embodiment, quantitative analysis using a calibration curve is performed. A calibration curve is usually created as follows. That is, multiple standard samples with known abundance (component amount, content) of the target molecular component are prepared, mass spectrometry is performed on these standard samples to obtain ionic strength, and the known abundance and measurement are performed. A calibration curve is created based on the ion intensity. In FIG. 3, the calibration curve creation process is shown in steps S1 to S4.

  When creating a calibration curve, the measurer first adjusts, that is, creates a standard sample. Specifically, as schematically shown in FIG. 4, for example, benzene (B), toluene (T), and xylene (X), the component amounts (mg) in the solvent are mb1 to mbn, mt1 to mtn, n (n is a positive integer) standard samples of mx1 to mxn are prepared.

  Next, the measurer alternately places the standard samples S1, S2,..., Sn for each molecule one by one at a predetermined position in a sample processing unit (not shown) in the soft ionization mass spectrometer 2 of FIG. Each is subjected to a predetermined process such as heating, and gas is generated from each standard sample. The generated gas is ionized by PI (photoionization) processing in step S2, and separated by the ion separation device 11 for each m / z value, and the intensity I (m / z, t) of the separated ions is detected as the ion intensity. Measured by device 12. This ionic strength I (m / z, t) is mass spectrometry data.

  Next, in step S3, the CPU 14 creates a mass chromatogram for each of the standard samples S1, S2,..., Sn, as shown in FIG. The mass chromatogram is a diagram showing the change over time of the ionic strength of benzene, toluene, and xylene having m / z values of 78, 92, and 106, respectively. In FIG. 5, for convenience, the mass chromatograms of the first sample S1, the second sample S2,... Of each molecule are shown on one graph. These mass chromatograms are displayed on the screen of the image display device 3 in FIG. 1 as necessary, or printed on paper or the like by the printer 4 so that the measurer can check them.

  In general, as a method of ionizing a gas, there are soft ionization such as photoionization (PI) and chemical ionization (CI) and electron impact ionization (EI) accompanied by cleavage of a parent ion (that is, a precursor ion). If the mass chromatogram as shown in FIG. 5 is performed based on the mass analysis data generated by EI, some of the ions generated in the ionization region in the ionizer 9 of FIG. In addition to the parent ions (precursor ions) of the molecules of z = 78), toluene (m / z = 92), and xylene (m / z = 106), there are also fragment ions derived from these parent ions. Then, a state occurs in which a fragment ion derived from a certain parent ion overlaps with another parent ion, and in this case, the mass chromatogram does not accurately represent the ionic strength of the component molecule.

  On the other hand, according to the PI treatment used in the present embodiment, the component molecules are not cleaved in the ionization region, the fragment ions are not generated, and only the parent ions are generated. Therefore, the mass chromatogram shown in FIG. 5 accurately represents the ionic strength of each component molecule of benzene, toluene, and xylene.

  Next, as shown in FIG. 6, the CPU 14 calculates the area intensity (area shown by oblique lines) of the peak waveform of each mass chromatogram. In FIG. 6, only the area intensity for the first standard sample S1 of each molecule is shown, but the area intensity is calculated for all standard samples of S1, S2,..., Sn. The area strengths Ib1, It1, Ix1,..., Ibn, Itn, Ixn thus obtained correspond to the abundances mb1, mt1, mx1,. ing.

  Next, the CPU 14 creates a calibration curve in step S4. Specifically, the abundances mb1, mt1, mx1,..., Mbn, mtn, mxn stored in advance when the standard samples S1, S2,..., Sn are adjusted, and the area intensities Ib1, It1 obtained in step S3. , Ix1,..., Ibn, Itn, Ixn, a calibration curve is created by calculation for each of benzene, toluene, and xylene, as shown in FIG. These calibration curves are stored in the file area or memory area of the memory 16 as mathematical expressions. In addition, each molecule | numerator of benzene, toluene, and xylene has the intrinsic | native ionization efficiency (value which shows the easiness to become an ion), and this ionization efficiency is not expressed, and is represented by the inclination of a calibration curve. The obtained calibration curve is displayed on the screen of the image display device 3 in FIG. 1 as necessary, or printed on paper or the like by the printer 4 so that the measurer can check them. When the calibration curve is obtained as described above, the gas quantitative analysis apparatus 1A in FIG. 1 is in a state where quantitative analysis can be performed on a sample containing benzene, toluene, and xylene as components.

  Next, regarding substances that are known to contain molecules of benzene, toluene, and xylene, the measurer wants to specify their quantity (component amount, content), that is, to quantify the quantity. The substance is placed as a sample in the sample processing section of the soft ionization mass spectrometer 2 shown in FIG. Then, an instruction is given to start the quantitative analysis by operating the input device 6 of FIG. The CPU 14 confirms the instruction in step S5 of FIG. 3 (YES in step S5), and performs quantitative analysis as follows.

  First, in step S6, the measurement time is started. In step S7, the mass spectrometry data I (m / z, t) is measured while scanning the m / z value using the soft ionization mass spectrometer 2 of FIG. This mass spectrometry data is data indicating how many ion intensities I are per m / z value when time t has elapsed from the start of measurement. Next, in step S8, the CPU 14 creates a mass spectrum as shown in FIG. 8 based on the mass analysis data I (m / z, t). This mass spectrum is a diagram showing ion intensity for each m / z value by a bar graph. From this mass spectrum, it can be seen that molecules having m / z values = 78, 92, and 106 are present in the measured gas in an amount corresponding to the displayed ion intensity. This mass spectrum is displayed on the screen of the image display device 3 in FIG. 1 as necessary, or printed on paper or the like by the printer 4 so that the measurer can check it.

  In general, according to a mass spectrum, a molecule can be specified by an m / z value, but the type of the molecule cannot be determined. In this embodiment, it can be seen that there are molecules with m / z values = 78, 92, 106 in the measured gas, but it cannot be determined that they are benzene, toluene, xylene. However, in this embodiment, since it is recognized in advance from the start of analysis that the sample to be measured seems to contain benzene, toluene, and xylene, the measurer observes the mass spectrum of FIG. Thus, it can be confirmed that the target molecules benzene, toluene and xylene are definitely contained in the sample. In this way, the measurer can determine the type of target molecule, that is, perform qualitative analysis.

  Next, in step S9, a mass chromatogram of molecules of m / z = 78, 92, 106 is created based on the mass analysis data I (m / z, t) obtained in step S7. The mass chromatogram is displayed on the screen of the image display device 3 in FIG. 1 as a diagram shown in FIG. 9, for example, or printed on paper or the like by the printer 4 as necessary. I can confirm. In this embodiment, it is known from the qualitative analysis in step S8 that these molecules are benzene, toluene, and xylene, respectively.

  Next, one of m / z = 78, 92, and 106 is selected in step S10, the area intensity is obtained by calculation (step S11), and the calibration curve in FIG. 7 obtained in step S4 is obtained. Substituting into to find the abundance. This is performed for all of m / z = 78, 92, 106, that is, for all of benzene, toluene, and xylene (step S13). As described above, the abundances of benzene, toluene and xylene, which are target molecules contained in the sample to be measured, are specified, that is, quantified.

  In this embodiment, mass spectrometry data is measured for ions obtained by PI that is soft ionization in steps S2 and S7 in FIG. 3, and mass chromatograms (FIG. 3) are obtained in steps S3 and S9 based on the mass analysis data. 5 and FIG. 9), a calibration curve was created based on the mass chromatogram, and the component amount was determined using the calibration curve. Since soft ionization is ionization that generates only parent ions without generating fragment ions, the created mass chromatogram accurately reflects the ionic strength of component molecules such as benzene. The obtained quantitative analysis results are very accurate and reliable as compared with the analysis using EI accompanied by generation of fragment ions.

  Further, in the present embodiment, each molecule of m / z value = 78, 92, 106 is not trapped and separated once as in GC-MS, and then mass analysis is performed. Since only the parent ion of each molecule of m / z value = 78, 92, 106 was accurately separated individually by PI and quantitative analysis was performed on each component, the quantitative analysis was performed in real time. It can be carried out. That is, according to the quantitative analysis of this embodiment, a very accurate and highly reliable quantitative analysis can be performed in real time.

  As can be seen from the above description, this embodiment is effective for quantifying the abundance (component amount, content) of molecules contained in a certain substance. It is also effective for quantifying the abundance of molecules contained in exhaust gas discharged from automobiles and other vehicles.

(Second Embodiment)
FIG. 10 shows another embodiment of a gas quantitative analysis apparatus capable of performing the gas quantitative analysis method according to the present invention. In this embodiment, it is assumed that the types of component molecules contained in a sample to be measured are generally known as in the above-described embodiment. In this embodiment, it is assumed that quantitative analysis is performed without using a calibration curve. In this embodiment, the abundance (component amount, content) of component molecules contained in the gas generated from the sample when the sample is heated is specified, that is, quantified.

  In the gas quantitative analysis method of the present embodiment, a sample containing various molecules can be measured, but in the following description, in order to facilitate understanding, benzene (m / z = 78), A substance whose components are three molecules of toluene (m / z = 92) and xylene (m / z = 106) is measured, and the amount of each molecule contained in the substance is quantified And As described above, the measurer recognizes in advance that the sample contains three kinds of component molecules, benzene, toluene, and xylene.

  FIG. 10 shows a gas quantitative analysis apparatus 1B of the present embodiment. The gas quantitative analyzer 1B includes a TG (Thermogravimetry) device 19, a soft ionization mass spectrometer 2, an image display device 3, a printer 4, an input device 6, and a control device 7B. The image display device 3, the printer 4, and the input device 6 are the same as those used in the embodiment of FIG.

  For example, as shown in FIG. 11, the TG device 19 includes a casing 21 that forms a sample chamber R 0, a heating furnace 22 as a heating means provided around the casing 21, and a balance beam provided inside the casing 21. 23. A gas supply source 24 is connected to the casing 21 by a pipe 26. The gas supply 24 emits a carrier gas, such as an inert gas, such as helium (He).

  The heating furnace 22 is configured by a heating device that uses, for example, a heating wire that generates heat when energized as a heat source, generates heat according to a command from the temperature control device 27, and is cooled as necessary. The temperature control device 27 includes a computer, a sequencer, a dedicated circuit, and the like. The temperature control device 27 outputs the temperature information of the heating furnace 22 over time, that is, the temperature information T (t) of the sample 31 over time as a signal. The balance beam 23 is swingably supported by a fulcrum 28. A sample dish 29 is provided at one end of the balance beam 23. A sample 31 to be analyzed for quantitative analysis is placed on the sample plate 29.

  An inclination detection sensor 32 is provided in the vicinity of the other end of the balance beam 23. The tilt detection sensor 32 includes, for example, a detection piece fixed to the balance beam 23, and a combination of a light receiving element and a light emitting element provided with the detection piece interposed therebetween. When the balance beam 23 tilts, the amount of light received by the light receiving element changes, and the amount of tilt of the balance beam 23 can be detected by this change in the amount of light. The tilt detection sensor 32 outputs a signal corresponding to the detected tilt amount.

  A beam tilting device 33 is provided at an appropriate position of the balance beam 23. The beam tilting device 33 has, for example, a combination of a magnet provided at an appropriate position of the balance beam 23 and an electromagnetic coil provided around the magnet. On the contrary, an electromagnetic coil may be provided in the balance beam 23 and a magnet may be provided around it. The electromagnetic coil generates a magnetic field when energized, and a force is applied to the magnet by the action of the magnetic field, and the balance beam 23 can be tilted and moved about the fulcrum 28 by this force. The current passed through the electromagnetic coil is controlled by the balance beam tilting device 34.

  The balance beam tilting device 34 receives the output signal of the tilt detection sensor 32 and controls the amount of current supplied to the beam tilting device 33 so that the output signal becomes a signal corresponding to zero tilt. By this feedback control, the balance beam 23 is controlled by the fulcrum 28 so as to always maintain a horizontal state. A weight calculation device 36 is attached to the balance beam tilting device 34. The weight calculating device 36 receives the amount of current supplied from the balance beam tilting device 34 to the beam tilting device 33 as information, and calculates a change in weight generated in the sample 31 based on the amount of current. The weight calculator 36 outputs the calculated weight change W (t) over time of the sample as a signal.

  The soft ionization mass spectrometer 2 in FIG. 10 includes a soft ionization device 9, an ion separation device 11, an ion intensity detection device 12, and an MS control device 13, as shown in FIG. This configuration is the same as the soft ionization mass spectrometer 2 shown in FIG. 2 in the first embodiment described above. In FIG. 11, a gas exhaust port 37 is provided in the vicinity of the sample dish 29 of the casing 21 of the TG device 19, and the gas exhaust port 37 and the gas input port of the soft ionization device 9 of the soft ionization mass spectrometer 2 are connected. They are connected by a gas transport tube 38.

  The gas transfer tube 38 is a capillary tube, that is, a tube having a small diameter, and is formed of glass, synthetic resin, rubber, or other appropriate material. Normally, the sample chamber R0 inside the casing 21 is at atmospheric pressure, and the ionization region inside the soft ionization apparatus 9 is in a vacuum or a reduced pressure state close thereto. The gas transport tube 38 maintains the pressure difference between the sample chamber R0 and the ionization region by adjusting the axial length of the tube and the inner diameter of the tube.

  In the TG device 19, the sample 31 is heated by the heating furnace 22 in accordance with a predetermined temperature raising program to raise the temperature. When the sample 31 to be heated is thermally changed (for example, decomposed) according to its own characteristics, gas is generated from the sample 31 and, at the same time, a change in weight occurs in the sample 31. The TG device 19 measures the change in the weight of the sample 31 via the balance beam 23. When gas is generated from the sample 31, the gas is transported by the carrier gas sent from the gas supply source 24 through the pipe 26, and is transported to the soft ionization device 9 through the gas transport tube 38.

  In FIG. 10, the control device 7B is configured using a computer. Specifically, the control device 7B has a CPU 14, a memory 16, and an ionization efficiency data table 39. As is well known, the CPU 14 performs calculations for realizing various functions by a computer and controls operations of various devices in the computer. The memory 16 is a storage medium for storing various information in a predetermined processing format, and is configured by a mechanical memory or a semiconductor memory. The memory 16 also includes a RAM and a ROM that are internal memories of the computer.

  Inside the memory 16, there are provided program software for executing quantitative analysis described later, a file area for storing various data, and a memory area for storing various data. The ionization efficiency data table 39 stores ionization efficiency values of various substances in the form of data tables. This information includes ionization efficiency values relating to benzene, toluene, and xylene, which are target molecular components in the present embodiment.

  Hereinafter, the flow of quantitative analysis performed by the apparatus having the above configuration will be described with reference to FIG. In performing this analysis, the measurer does not need to prepare a calibration curve in advance. First, the measurer places the sample to be analyzed on the sample plate 29 at the tip of the balance beam 23 of the TG device 19 of FIG. Then, the input device 6 in FIG. 10 is operated to instruct the start of analysis. When the start of analysis is confirmed in step S31 in FIG. 12 (YES in step S31), the CPU 14 causes the TG device 19 in FIG. 11 to perform TG measurement in step S32, and in step S33, soft ionization mass spectrometry in FIG. The apparatus 2 is caused to measure mass spectrometry data.

  Specifically, in the TG device 19, first, the temperature of the sample 31 is raised by the heating furnace 22 according to a predetermined temperature raising program. When the sample 31 undergoes a structural change such as decomposition or desorption according to its physical properties at this temperature rise, the molecules related to the structural change become gas and are separated from the sample 31 and the weight of the sample 31 is reduced. This change in weight is detected by the tilt movement of the balance beam 23 and is output from the weight calculation device 36 as weight change data W (t). A representation of the weight change data W (t) as a diagram is a TG curve, for example, a diagram as shown in FIG.

  In the TG curve shown in FIG. 13A, the horizontal axis represents temperature (° C.) and the vertical axis represents weight (mg). Since the temperature change of the sample can be grasped as a time change based on the output signal of the temperature control device 27 of FIG. 11, the horizontal axis of FIG. 13 (a) can be the time (t) axis. In the TG curve shown in FIG. 13A, the weight W1 decreases between the temperature T1 and the temperature T2. From this, it can be seen that gas of weight W1 was generated from the sample 31 in this time zone. The gas generated here is not a single component gas but a mixed gas of benzene, toluene and xylene. Of course, the measurer cannot recognize at this point that the generated gas is that kind of gas.

  By measuring the mass spectrometry data in step S33, the ion intensity I (m / z, t) for each m / z value when time t has elapsed from the start of measurement is measured as mass spectrometry data. Next, in step S34, the CPU 14 creates a mass spectrum as shown in FIG. 8 based on the mass analysis data I (m / z, t). This mass spectrum is a diagram showing ion intensity for each m / z value by a bar graph. From this mass spectrum, it can be seen that molecules having m / z values = 78, 92, and 106 are present in the measured gas in an amount corresponding to the displayed ion intensity. This mass spectrum is displayed on the screen of the image display device 3 in FIG. 10 as necessary, or printed on paper or the like by the printer 4 so that the measurer can check it.

  In general, according to a mass spectrum, a molecule can be specified by an m / z value, but the type of the molecule cannot be determined. In this embodiment, it can be seen that there are molecules with m / z values = 78, 92, 106 in the measured gas, but it cannot be determined that they are benzene, toluene, xylene. However, in this embodiment, since it is recognized in advance from the start of analysis that the sample to be measured seems to contain benzene, toluene, and xylene, the measurer observes the mass spectrum of FIG. Thus, it can be confirmed that the target molecular components benzene, toluene and xylene are definitely included in the sample. In this way, the measurer can determine the type of the target molecular component, that is, perform qualitative analysis.

  Next, in step S35, a mass chromatogram of molecules of m / z = 78, 92, 106 is created based on the mass analysis data I (m / z, t) obtained in step S33. The mass chromatogram is displayed on the screen of the image display device 3 in FIG. 10 as a diagram shown in FIG. 9, for example, or printed on paper or the like by the printer 4 as necessary. I can confirm. In the present embodiment, it is known from the qualitative analysis in step S34 that these molecules are benzene, toluene, and xylene, respectively.

  When the mass chromatogram shown in FIG. 9 is superimposed on the TG curve shown in FIG. 13A with the unit length of the temperature axis (horizontal axis) aligned, a composite diagram shown in FIG. 13B is obtained. The CPU 14 can display this composite diagram on the image display device 3 and the printer 4 in FIG. As is apparent from this composite diagram, it can be seen that the decrease in weight in the TG curve and the peak waveform in the mass chromatogram coincide with each other in time.

  Next, in step S36, one of m / z = 78, 92, 106 is selected, and in step S37, the area intensity of the molecule is obtained by calculation, and in step S38, the area intensity is determined by the ionization efficiency of the molecule. It is corrected. This correction is performed in order to compensate that the ionization rate with respect to the unit weight differs among the substances. The calculation of the area intensity and the correction of the ionization efficiency are performed for all molecules of m / z = 78, 92, 106 (step S39).

  Next, in step S40, calculation of the abundance of each molecule, that is, calculation of quantification is performed. Specifically, the ratio of the area intensity on the mass chromatogram for each component of benzene, toluene, and xylene obtained in steps S36 to S39 is calculated, and the total amount of generated gas obtained by the TG device 19 in step S32. The weight W1 is assigned to each component based on the area intensity ratio of each component. Thereby, the abundance (component amount, content) for each component of benzene, toluene, and xylene is accurately obtained by calculation, and the quantitative analysis is completed.

  In the present embodiment, in step S33 of FIG. 12, mass spectrometry data is measured for ions obtained by PI (photoionization) that is soft ionization, and a mass chromatogram (see FIG. 9) based on the mass analysis data. And the amount of each component molecule was determined based on the mass chromatogram. Since soft ionization is ionization that generates only parent ions without generating fragment ions, the created mass chromatogram accurately reflects the ionic strength of component molecules such as benzene. The obtained quantitative analysis results are very accurate and reliable as compared with the analysis using EI accompanied by generation of fragment ions.

  Further, in the present embodiment, each molecule of m / z value = 78, 92, 106 is not trapped and separated once as in GC-MS, and then mass analysis is performed. Since only the parent ion of each molecule of m / z value = 78, 92, 106 was accurately separated individually by PI and quantitative analysis was performed on each component, the quantitative analysis was performed in real time. It can be carried out. That is, according to the quantitative analysis of this embodiment, a very accurate and highly reliable quantitative analysis can be performed in real time.

  In the embodiment shown in FIGS. 1 to 3, quantitative analysis was performed using a calibration curve. This calibration curve creation process must be performed after preparing a large number of standard samples, which is very troublesome and requires a long time. On the other hand, in this embodiment, since quantitative analysis can be performed without using a calibration curve, quantitative analysis can be performed easily and in a short time.

(Modification)
In the above embodiment, if the ionization efficiency is different between each component molecule contained in the generated gas, when each component molecule is PI, that is, soft ionization, even if the abundance of each component is the same, it is ionized. There is a risk of variations in the amount of ions after. In the above embodiment, ionization efficiency values for various substances are stored in advance in the data table 39 of FIG. 10, and after obtaining the area intensity of the mass chromatogram in step S37 of FIG. The accuracy of quantitative analysis is improved by correcting the area intensity in step S38 based on the ionization efficiency.

  In addition, there is no problem if the values of ionization efficiency for various molecules are provided by literature values, but there are some substances for which the value of ionization efficiency is not provided. For such materials, the ionizer must determine the ionization efficiency. In this regard, it has already been explained that the slope of the calibration curve shown in FIG. 7 indicates the ionization efficiency. For substances whose ionization efficiencies are not given as literature values etc., firstly, a diagram corresponding to a calibration curve (that is, the relationship between the abundance of the molecule and the area intensity on the mass chromatogram of the molecule is represented. The amount of ionization efficiency of the substance can be known by determining the abundance / area intensity diagram) and knowing the slope of the diagram.

  The problem here is when the target substance for which ionization efficiency is to be obtained is volatile at room temperature (15 to 30 ° C.), and the target substance itself is mass-chromatized at a predetermined measurement location. This is when measuring grams. As described above, when obtaining a calibration curve, it is necessary to create a plurality of mass chromatograms as shown in FIG. 9 with different amounts of target objects. This is because the peak waveform already exists at time zero on the horizontal axis of the mass chromatogram, and the total area intensity of the peak waveform cannot be accurately calculated.

  The present inventor has repeatedly considered this point. As a result, when the ionization efficiency of the volatile substance is obtained as the slope of the abundance-area intensity diagram (substantially a calibration curve), a volatile substance having a known weight is contained in a container with a pinhole. Thus, the inventors came up with the idea that it is effective to obtain ion area intensity of mass chromatogram by ionizing the gas from the pinhole with PI. In such a container, for example, as shown in FIG. 14, a volatile substance 42 to be measured is placed in a bottomed cylindrical container body 41, and a lid 44 having a pinhole 43 is placed in the opening of the container body 41. It is formed by fixing.

  According to this sample storage method, the volatile substance stored in the container with the pinhole does not go out of the container at the beginning of the measurement, and after a certain amount of time, goes out of the container and is ionized by PI. The ionic strength is measured. Accordingly, the entire peak waveform on the mass chromatogram as shown in FIG. 9 can be reliably obtained, and an accurate abundance-area intensity diagram can be obtained, whereby a substance having volatility at room temperature can be obtained. Accurate ionization efficiency can be obtained.

  Note that the size of the pinhole is desirably such that the change in weight is small at room temperature (the change in weight is 3.0% / s or less at normal temperature). Also, according to experiments, it was appropriate that the pinhole diameter in a cylindrical container having a diameter of 5 mm was about 50 μm.

(Third embodiment)
FIG. 15 shows still another embodiment of a gas quantitative analysis apparatus capable of performing the gas quantitative analysis method according to the present invention. In this embodiment, unlike the above-described embodiments, it is assumed that the type of component molecules contained in the sample to be measured is not known to the measurer at all. Therefore, unlike the first embodiment (FIG. 1) and the second embodiment (FIG. 10), it is necessary to perform a highly accurate qualitative analysis. In this embodiment, the quantitative analysis is performed without using a calibration curve as in the case of the second embodiment (FIG. 10). In the present embodiment, the abundance (component amount, content) of molecules contained in the gas generated from the sample when the sample is heated is specified, that is, quantified.

  In the gas quantitative analysis method of the present embodiment, a sample containing various molecules can be measured, but in the following description, in order to facilitate understanding, benzene (m / z = 78), A substance whose components are three molecules of toluene (m / z = 92) and xylene (m / z = 106) is measured, and the amount of each component molecule contained in the substance is quantified. Shall. As described above, the measurer does not recognize that the sample contains three kinds of component molecules of benzene, toluene, and xylene.

  FIG. 15 shows a gas quantitative analyzer 1C of this embodiment. This gas quantitative analyzer 1C has a TG device 19, a soft ionization mass spectrometer 2, an EI mass analyzer 5, an image display device 3, a printer 4, an input device 6, and a control device 7C. The image display device 3, the printer 4, and the input device 6 are the same as those used in the embodiment of FIGS. The soft ionization mass spectrometer 2 and the TG device 19 are the same as those used in the embodiment of FIG. A description of these same devices will be omitted.

  For example, as shown in FIG. 16, the EI mass spectrometer 5 includes an electron impact ionization device (hereinafter also referred to as an EI device) 49, an ion separation device 51, an ion intensity detection device 52, and their operations. And an MS control device 53 for controlling. The ion separation device 51 and the ion intensity detection device 52 have the same configuration as the ion separation device 11 and the ion intensity detection device 12 used in the soft ionization mass spectrometer 2, respectively, and thus description thereof is omitted.

  The EI device 49 is a device that ionizes molecules constituting the introduced gas. The EI device 49 is a technique for generating ions by, for example, causing electrons to collide with molecules and emitting electrons in the molecules. The electrons applied to the molecules can be taken out as thermal electrons from the filament by energizing the filament, for example. Ions corresponding to molecules are sometimes referred to as parent ions or precursor ions. In addition, when electrons collide with the molecule, the molecule is cleaved to generate fragment ions together with the parent ion within a wide m / z value range. The parent ion gives information related to the molecular weight of the molecules that make up the gas, and the fragment ion gives information about the structure of the molecules.

  The gas input port of the soft ionization device 9 of the soft ionization mass spectrometer 2 and the gas input port of the EI device 49 of the EI mass spectrometer 5 are respectively connected to the gas exhaust port 37 of the TG device 19 by the gas transfer tube 48. . The gas transport tube 48 may have a configuration in which one capillary tube is provided between the gas exhaust port 37 and the soft ionization device 9 and between the gas exhaust port 37 and the EI device 49, or You may form with one capillary tube provided with the structure which can branch and convey gas to 2 directions.

  In the TG device 19, the sample 31 is heated by the heating furnace 22 in accordance with a predetermined temperature raising program to raise the temperature. When the sample 31 to be heated is thermally changed (for example, decomposed) according to its own characteristics, a change in weight occurs in the sample 31 and gas is generated from the sample 31 at the same time. The TG device 19 measures the change in the weight of the sample 31 via the balance beam 23. When the gas is generated from the sample 31, the gas is sent out by the carrier gas sent from the gas supply source 24 through the pipe 26, and is transported to the soft ionization device 9 and the EI device 49 through the gas transport tube 48.

  The control device 7C in FIG. 15 is configured using a computer. Specifically, the control device 7C includes a CPU 14, a memory 16, a NIST (National Institute of Standards and Technology) table 17, and an ionization efficiency table 18. As is well known, the CPU 14 performs calculations for realizing various functions by a computer and controls operations of various devices in the computer. The memory 16 is a storage medium for storing various information in a predetermined processing format, and is configured by a mechanical memory or a semiconductor memory. The memory 16 also includes a RAM and a ROM that are internal memories of the computer.

  The NIST table 17 is a well-known data table that stores mass spectra when various substances are ionized by EI treatment and mass analysis is performed, and about 1.3 million compounds composed of a single component that is not a mixture. The mass spectrum of is stored. For example, as shown in FIG. 17, an m / z value, a compound name, and an EI mass spectrum are stored in association with each other. FIG. 17 shows an example of data corresponding to m / z = 78, 92, and 106 as an example.

  For example, in FIG. 15, when the input device 6 is operated to search for a compound of (m / z) = 78 in the NIST table 17 through the CPU 14, the search result shown in FIG. Displayed above. When (m / z) = 78 is designated, as shown in the left column 46 of FIG. 18, 17 types of compounds including Arsine and Benzene in FIG. 17 correspond to (m / z) = 78. To be listed as As for other (m / z) values, a plurality of compounds are usually listed.

  In the ionization efficiency table 18 of FIG. 15, for example, as shown in FIG. 19, ionization efficiencies of various compounds are stored for each (m / z) value. These values are obtained in advance by experiments or are literature values.

  Hereinafter, the flow of quantitative analysis performed by the apparatus having the above configuration will be described with reference to FIG. In performing this analysis, the measurer does not need to prepare a calibration curve in advance. First, the measurer places the sample to be analyzed on the sample plate 29 at the tip of the balance beam 23 of the TG device 19 of FIG. Then, the input device 6 in FIG. 15 is operated to instruct the start of analysis. When the start of analysis is confirmed in step S51 in FIG. 20 (YES in step S51), the CPU 14 causes the TG device 19 in FIG. 16 to perform TG measurement in step S52, and in step S53, soft ionization mass spectrometry in FIG. Both the apparatus 2 and the EI mass spectrometer 5 are caused to measure mass spectrometry data.

  For example, a TG curve shown in FIG. 13 is obtained by the TG measurement. Further, by measuring the mass spectrometry data in step S53, the ion intensity I (m / z, t) for each m / z value when time t has elapsed from the start of measurement is based on the mass spectrometry data and EI based on soft ionization. Measured in both forms of mass spectrometry data. As is well known, mass analysis data based on soft ionization is data of only parent ions not including fragment ions (cleavage ions), and mass analysis data based on EI is data on both parent ions and fragment ions. .

Next, in step S54, the CPU 14 qualifies based on both the mass analysis data I _S (m / z, t) based on soft ionization and the mass analysis data I _E (m / z, t) based on EI. Perform analysis. This qualitative analysis is an analysis for specifying the type of molecules contained in the sample 31. In this embodiment, the case where benzene, toluene, and xylene are included in the sample 31 is considered. However, by performing this qualitative analysis, the component molecules are specified for the first time. In this embodiment, very accurate qualitative analysis is realized by using both soft ionization and EI. This qualitative analysis will be described later.

After the above qualitative analysis is completed, in step S55, based on the mass spectrometry data I _S (m / z, t) obtained in step S53, the molecules of m / z = 78, 92, 106 are analyzed. Create a mass chromatogram. The mass chromatogram is displayed on the screen of the image display device 3 in FIG. 15 as a diagram shown in FIG. 9, for example, or printed on paper or the like by the printer 4 as necessary. I can confirm. In this embodiment, it is known from the qualitative analysis in step S54 that these molecules are benzene, toluene, and xylene, respectively.

  When the mass chromatogram shown in FIG. 9 is superimposed on the TG curve shown in FIG. 13A with the unit length of the temperature axis (horizontal axis) aligned, a composite diagram shown in FIG. 13B is obtained. The CPU 14 can display this composite diagram on the image display device 3 and the printer 4 in FIG. 15 as necessary. As is apparent from this composite diagram, it can be seen that the decrease in weight in the TG curve and the peak waveform in the mass chromatogram coincide with each other in time.

  Next, in step S56, one of m / z = 78, 92, 106 is selected, and in step S57, the area intensity for the molecule is obtained by calculation, and in step S58, the area intensity is determined by the ionization efficiency of the molecule. It is corrected. This correction is performed in order to compensate that the ionization rate with respect to the unit weight differs among the substances. The calculation of the area intensity and the correction of the ionization efficiency are performed for all molecules of m / z = 78, 92, 106 (step S59).

  Next, in step S60, calculation of the component amount of each component molecule, that is, calculation of quantification is performed. Specifically, the ratio of the area intensity on the mass chromatogram for each component of benzene, toluene, and xylene obtained in steps S56 to S59 is calculated, and the total amount of generated gas obtained by the TG device 19 in step S52. The weight W1 is assigned to each component based on the area intensity ratio of each component. Thereby, the abundance (component amount, content) for each component of benzene, toluene, and xylene is accurately obtained by calculation, and the quantitative analysis is completed.

  In the present embodiment, in step S53 of FIG. 20, mass spectrometry data is measured for ions obtained by PI that is soft ionization, and a mass chromatogram (see FIG. 9) is created based on the mass analysis data. Based on the mass chromatogram, the component amount of each component molecule was determined. Since soft ionization is ionization that generates only parent ions without generating fragment ions, the created mass chromatogram accurately reflects the ionic strength of component molecules such as benzene. The obtained quantitative analysis results are very accurate and reliable as compared with the analysis using EI accompanied by generation of fragment ions.

  Further, in the present embodiment, each molecule of m / z value = 78, 92, 106 is not trapped and separated once as in GC-MS, and then mass analysis is performed. Since only the parent ion of each molecule of m / z value = 78, 92, 106 was accurately separated individually by PI and quantitative analysis was performed on each component, the quantitative analysis was performed in real time. It can be carried out. That is, according to the quantitative analysis of this embodiment, a very accurate and highly reliable quantitative analysis can be performed in real time.

  In the embodiment shown in FIGS. 1 to 3, quantitative analysis was performed using a calibration curve. This calibration curve creation process must be performed after preparing a large number of standard samples, which is very troublesome and requires a long time. On the other hand, in this embodiment, since quantitative analysis can be performed without using a calibration curve, quantitative analysis can be performed easily and in a short time.

(First qualitative analysis)
Now, the first analysis method will be described based on the flowchart shown in FIG. 21 for the qualitative analysis performed in step S54 of FIG. Until the qualitative analysis is completed, it is not known at all whether the sample 31 contains such component molecules.

When the qualitative analysis in step S54 in FIG. 20 is started, for example, a mass spectrum shown in FIG. 22A is obtained based on the EI mass spectrometry data I _E (m / z, t) measured in step S53. The m / z values of each component of benzene, toluene, and xylene are 78, 92, and 106, respectively. Fragment ions unique to EI treatment are generated according to the molecular structure of each component, and are in a wide range. An ion peak appears over the m / z value. On the other hand, based on the soft ionization mass spectrometry data I _S (m / z, t) measured in step S53, for example, a mass spectrum shown in FIG. 22B is obtained. Since PI, which is soft ionization, does not generate fragment ions but generates only parent ions, three types of parent ions (m / z) = 78, 92, and 106 appear.

  The CPU 14 in FIG. 15 stores the EI measurement data in FIG. 22A in the file 1 in step S71 in FIG. In step S72, the PI measurement data shown in FIG. Next, in step S73, the CPU 14 determines (m / z) = 78, 92, 106 of the generated gas from the PI measurement data of FIG. It is determined that there are three, and these are stored in the memory. At this time, the substance name of the generated gas is unknown. Further, in step S74, the CPU 14 determines the ion intensity ratio d of the component molecules of the generated gas from the PI measurement data of FIG. 22B stored in the file 2. In this embodiment, the ion intensity ratios d of (m / z) = 78, 92, and 106 were 50, 100, and 75, respectively. The ionic strength ratio is a concentration ratio with respect to the whole mixture of each component molecule.

  Next, in step S75, the CPU 14 selects “78”, which is the smallest of the three (m / z), and in step S76, the NIST data of this ion species is obtained from the NIST table 17 as a reference mass spectrum. Read as data. At this time, the NIST table 17 is searched for a large number of compounds determined to have (m / z) = 78, including the benzene mass spectrum (m / z = 78) shown in FIG. The

  Next, in step S77, the read reference data are multiplied by the ion intensity ratio d corresponding to (m / z) = 78. This is a standardized value of the NIST data, but in the actual generated gas, the intensity differs between the molecular components as shown in FIG. 22 (b), so that the intensity difference is compensated. Is to be done.

  Next, in step S78, the ionization efficiency IZ of the substance of (m / z) = 78 is read from the ionization rate table 18 of FIG. 15, and the ionization efficiency is multiplied by NIST data in step S79. This is performed to compensate for the difference in the ionization efficiency between the molecules in the actual generated gas, while the NIST data is a standardized value.

  As described above, the reference data regarding the molecule of (m / z) = 78 is generated, and these data are stored in the file 3. Then, among the (m / z) stored in the memory 1 in step S73, (m / z) = 78 where the processing is completed is removed (step S80). In step S81, it is determined whether or not processing has been completed for all component molecules. If not (NO in step S81), the process returns to step S75, and the remaining (m / z) = 92 and 106 are The process of generating the reference EI data (step S79) is repeated.

  In these treatments, treatment is performed on toluene corresponding to (m / z) = 92 and other molecules corresponding to (m / z) = 92 shown in FIG. Further, processing is performed on xylene with (m / z) = 106 and other molecules corresponding to (m / z) = 106 shown in FIG. When the processing up to the last (m / z) is completed, all the reference EI data corresponding to (m / z) = 78, 92, 106 are accumulated in the file 3 in step S79. .

  Thereafter, in step S82, the CPU 14 synthesizes three types of EI data (m / z) = 78, 92, and 106 stored in the file 3 in step S79 one by one. The synthesis result is, for example, a mass spectrum as shown in FIG. Thereafter, the synthesized EI data is compared with the EI measurement data (see FIG. 22A) stored in the file 1 in step S71. Specifically, the hit rate% is calculated by comparing (m / z) and ionic strength according to a known algorithm. When the hit rate% is equal to or higher than a predetermined value, the names of the three substances and the mixing ratios constituting the synthetic EI data at that time are determined as analysis results or analysis result candidates.

  As described above, according to the present embodiment, the parent ion in the generated gas is estimated (step S73), the NIST data of the estimated parent ion is read (steps S75 to S81), and the read NIST data for each component molecule. Then, the synthesis data is compared with the EI measurement data (steps 82 to 84) to repeat the process of determining the molecules contained in the EI measurement data.

  According to this method, the EI measurement data obtained by measurement is not directly searched with a large amount of NIST data, but the molecular weight and generated gas number data obtained by PI measurement data are effectively used to perform NIST. The data is compared with the EI measurement data in a state where the data is narrowed down in advance. Therefore, the determination result finally obtained is very accurate, the number of data to be calculated can be greatly reduced, and the memory capacity and calculation processing time can be greatly reduced.

(Second qualitative analysis)
Next, the second analysis method will be described based on the flowchart shown in FIG. 25 for the qualitative analysis performed in step S54 of FIG. As described in the first qualitative analysis shown in FIG. 21, EI measurement data (see FIG. 22A) is obtained by the EI mass spectrometer 5 in FIG. In addition, PI measurement data (see FIG. 22B) is obtained by the PI mass spectrometer 2. The EI measurement data includes fragment ions, and the PI measurement data includes only parent ions without fragment ions.

  The CPU 14 in FIG. 15 stores the EI measurement data in FIG. 22A in the file 1 in step S101 in FIG. In step S102, the PI measurement data shown in FIG. Next, in step S103, the CPU 14 determines (m / z) = 78, 92, 106 of the generated gas from the PI measurement data of FIG. It is determined that there are three, and these are stored in the memory. At this time, the substance name of the generated gas is unknown. Further, in step S104, the CPU 14 determines the ionic strength ratio d of the component molecules of the generated gas from the PI measurement data of FIG. 22B stored in the file 2. In this embodiment, the ion intensity ratios d of (m / z) = 78, 92, and 106 were 50, 100, and 75, respectively. The ionic strength ratio is a concentration ratio with respect to the whole mixture of each component molecule.

  Next, in step S105, the CPU 14 selects the smallest one of the three (m / z) 78, and in step S106, the NIST data of this ion species is used as reference mass spectrum data from the NIST table 17. read out. At this time, the NIST table 17 is searched for a large number of compounds determined to have (m / z) = 78, including the benzene mass spectrum (m / z = 78) shown in FIG. The

  Next, in step S107, the read-out reference data are multiplied by the ion intensity ratio d corresponding to (m / z) = 78. This is a standardized value of the NIST data, but in the actual generated gas, the intensity differs between the molecular components as shown in FIG. 22 (b), so that the intensity difference is compensated. Is to be done.

  Next, in step S108, the ionization rate IZ of the substance of (m / z) = 78 is read from the ionization efficiency table 18 of FIG. 15, and the ionization efficiency is multiplied by NIST data in step S109. This is performed to compensate for the difference in the ionization efficiency between the molecules in the actual generated gas, while the NIST data is a standardized value.

  As described above, the reference data regarding the molecule of (m / z) = 78 is generated, and these data are stored in the file 3. Then, among the (m / z) stored in the memory 1 in step S103, (m / z) = 78 where the processing is completed is removed (step S110). In step S111, the hit rate for the EI measurement data stored in the file 1 in step S101 is calculated for each of the plurality of reference data regarding the molecule of (m / z) = 78. The hit rate is calculated by comparing the reference data and the EI measurement data according to a known algorithm with respect to (m / z) and ionic strength. If a plurality of reference data has a hit rate equal to or higher than a predetermined hit rate, the compound name is stored in the file 4 in step S113.

  This search process is performed for all the compounds read out at (m / z) = 78, and when the search is completed, the mass spectra of all the hit compounds stored in the file 4 are obtained in step S101 in step S114. Subtract from the EI measurement data in file 1. Thereby, it is possible to narrow down the number of reference data when performing search processing for the compounds corresponding to the remaining (m / z) = 92,106.

  Generally, mass spectrum search algorithms perform profile fitting using signals with high ionic strength and signals with high molecular weight, so in the case of mixed gases, components with low molecular weight are difficult to distinguish from fragments of large molecules and are qualitative. It is difficult. On the other hand, if the search process is performed in order from the molecule with the smallest (m / z) as in the present embodiment, the molecular component that has conventionally been difficult to perform the search due to the low molecular weight is surely to be inspected. Will be able to.

  As described above, after the search for the molecule of (m / z) = 78 is completed and the result is stored in the file 4, the search is similarly performed for the remaining molecules of (m / z) = 92 and 106. (NO in step S115 to S114) As a result, molecules having a high hit rate (m / z) = 92, 106 are stored in the file 4. After the search process for all the component molecules is completed (YES in step S115), in step 116, the molecule name and the mixture ratio stored in the file 4 are determined as analysis results or analysis result candidates.

  As described above, according to the present embodiment, the parent ion in the generated gas is estimated (step S103), the NIST data of the estimated parent ion is read (steps S105 to S110), and the read NIST data for each component molecule. By repeating the process of comparing the EI measurement data with the EI measurement data (step 111), it was decided to determine what the component molecules included in the EI measurement data were.

  According to this method, the EI measurement data obtained by measurement is not directly searched with a large amount of NIST data, but the molecular weight and generated gas number data obtained by PI measurement data are effectively used to perform NIST. The data is compared with the EI measurement data in a state where the data is narrowed down in advance. Therefore, the determination result finally obtained is very accurate, the number of data to be calculated can be greatly reduced, and the memory capacity and calculation processing time can be greatly reduced.

(Fourth embodiment)
FIG. 26 shows still another embodiment of the gas quantitative analysis method and apparatus according to the present invention. The gas quantitative analyzer 1D shown here is different from the gas quantitative analyzer 1C shown in FIG. 15 in that the mass spectrometer 55 has been modified and will be described in detail below. Note that the same members as those in the embodiment of FIG. 15 are denoted by the same reference numerals, and the description thereof will be omitted.

  In the gas quantitative analyzer 1C shown in FIG. 15, the EI mass spectrometer 5 and the soft ionization mass spectrometer 2 are installed as separate apparatuses. On the other hand, in this embodiment, the EI mass spectrometer and the soft ionization mass spectrometer are configured by one mass spectrometer 55. FIG. 27 shows the TG device 19 and the mass spectrometer 55 in detail. The configuration shown in FIG. 27 is substantially the same as the configuration disclosed in FIG. 6 of the international publication WO2007 / 108211 pamphlet. The TG device 19 has the same configuration as the TG device 19 shown in FIG.

  The mass spectrometer 55 includes a casing 58 that forms the analysis chamber R1, an ionization device 59 provided in the analysis chamber R1, a quadrupole filter 61 as ion separation means, an ion detection device 62, and an MS control device. 63. The MS control device 63 controls the operation of each element of the ionization device 59, the quadrupole filter 61, and the ion detection device 62. Further, the MS control device 63 includes an electrometer that calculates the intensity of ions detected by the ion detection device 62.

  A turbo molecular pump 67 and a rotary pump 68 are attached to the casing 58. The rotary pump 68 roughly depressurizes the pressure in the analysis chamber R1, and the turbo molecular pump 67 further depressurizes the analysis chamber R1 roughly depressurized by the rotary pump 68 to a vacuum state or a pressure reduction state close thereto.

  As is well known, the quadrupole filter 61 has four rod-shaped electrodes. A scanning voltage in a state where a high-frequency AC voltage whose frequency changes with time and a DC voltage of a predetermined magnitude are superimposed is applied to these electrodes. By applying the high-frequency scanning voltage to the quadrupole, ions passing between the quadrupoles are separated for each m / z value of the molecule, and the separated ions are detected at the subsequent stage. 62.

  The ion detector 62 has an ion deflector and an electron multiplier (both not shown). Ions selected by the quadrupole filter 61 are collected by an ion deflector into an electron multiplier and output as an electrical signal. The signal is counted by an electrometer and output as an ion intensity signal.

  The ionization device 59 has a PI (Photo-ionization) lamp 64 as an optical emission means and an EI (Electron Ionization) device 65. The lamp 64 passes through the casing 58 and is fixed to the casing 58. The fixed portion is hermetically sealed by a sealing member. The light emitting surface of the lamp 64 faces the EI device 65. The end of the lamp 64 opposite to the light emission surface is located outside the casing 58.

  The EI device 65 includes a filament (not shown) as electron generating means for emitting electrons when energized, an external electrode (not shown) surrounding the filament, and an internal electrode (not shown) paired with the external electrode. Z). Both the external electrode and the internal electrode have a structure capable of transmitting light from the lamp 64, for example, a structure using a net-like shape, a spiral shape, or a translucent member.

  In the EI device 65, when energization is performed on the filament, thermoelectrons are generated, and the thermoelectrons are accelerated by a voltage applied to the external electrode and the internal electrode. If a gas is introduced into the EI device 65, the gas is ionized by the collision of thermionic electrons. On the other hand, when the lamp 64 is lit, the gas introduced into the EI device 65 is soft ionized by light. If energization of the filament is performed for a predetermined time, and then the power is stopped and the lamp 64 is lit for a predetermined time, both EI and soft ionization can be performed for one gas introduction. Moreover, both EI and soft ionization can be performed for one gas introduction by alternately repeating energization / interruption of the filament and turning on / off the lamp 64 within a predetermined time in a short time. it can.

  The gas exhaust port 37 of the TG device 19 and the gas input port of the ionization device 59 of the mass spectrometer 55 are connected by a gas transfer tube 69. This gas transfer tube 69 is the same as the gas transfer tube 38 of FIG. 11, and is formed of, for example, a capillary tube. The sample chamber R0 inside the casing 21 of the TG device 19 is at atmospheric pressure, and the ionization region inside the ionization device 59 is in a vacuum or a reduced pressure state close thereto. The gas transfer tube 69 maintains the pressure difference between the sample chamber R0 and the ionization region by adjusting the axial length of the tube and the inner diameter of the tube.

  The configuration of the control device 7D of FIG. 26 is basically the same as the control device 7C used in the embodiment of FIG. The flow of control executed by the CPU 14 and quantitative analysis program in FIG. 26 is basically the same as in the previous embodiment shown in FIG. What is different is the control method of the soft ionization mass spectrometer 2 and the EI mass spectrometer 5. In the embodiment of FIG. 15, since the soft ionization mass spectrometer 2 and the EI mass spectrometer 5 are provided separately from each other, they are controlled independently of each other. On the other hand, in the present embodiment shown in FIG. 27, since a common ionization region is formed by the PI lamp 64 and the EI device 65, they cannot be operated at exactly the same timing.

  Therefore, the PI by the PI lamp 64 and the EI by the EI device 65 are performed while being shifted from each other. For example, a control is conceivable in which one of PI and EI is performed at the beginning of a predetermined length of ionization treatment time, and the other of PI or EI is performed in the remaining time. On the other hand, the control of alternately repeating PI and EI for a short time can be considered. According to the present embodiment, even if the amount of gas generated from the sample 31 is small, mass analysis based on PI (that is, soft ionization) and mass analysis based on EI can be accurately performed.

1 is a circuit block diagram showing an embodiment of a gas quantitative analysis apparatus according to the present invention. FIG. 2 is a structural diagram of a main part of FIG. 1. It is a flowchart which shows one Embodiment of the gas quantitative analysis method which concerns on this invention. It is a schematic diagram of a standard sample. It is a figure which shows an example of a mass chromatogram. It is a figure which shows the example of calculation of area intensity. It is a figure which shows an example of a calibration curve. It is a figure which shows an example of a mass spectrum. It is a figure which shows the mass chromatogram corresponding to the mass spectrum of FIG. It is a circuit block diagram which shows other embodiment of the gas quantitative analysis apparatus which concerns on this invention. FIG. 11 is a structural diagram of a main part of FIG. 10. It is a flowchart which shows other embodiment of the gas quantitative analysis method which concerns on this invention. It is a figure which shows the relationship between a TG curve and a TG curve, and a mass chromatogram. It is side surface sectional drawing which shows an example of a sample container. It is a circuit block diagram which shows other embodiment of the gas quantitative analysis apparatus which concerns on this invention. FIG. 16 is a structural diagram of a main part of FIG. 15. It is a figure which shows the example of a memory | storage of the information in a database. It is a figure which shows the example of a display of the information of FIG. It is a figure which shows the example of a memory | storage of the information in another database. It is a flowchart which shows other embodiment of the gas quantitative analysis method which concerns on this invention. It is a flowchart of an example of the main processes of FIG. It is a figure which shows an example of EI measurement data and PI measurement data. It is a figure which shows an example of the mass spectrum memorize | stored in the database. It is a figure which shows an example of the mass spectrum memorize | stored and the mass spectrum memorize | stored in the database. It is a flowchart of the other example of the main processes of FIG. It is a circuit block diagram which shows other embodiment of the gas quantitative analysis apparatus which concerns on this invention. FIG. 27 is a structural diagram of the main part of FIG. 26.

Explanation of symbols

1A, 1B, 1C, 1D. 1. Gas quantitative analyzer, Soft ionization mass spectrometer,
3. 3. image display device; Printer, 5. EI mass spectrometer, 6. Input device,
7A, 7B, 7C, 7D. Control device, 9. 10. soft ionizer, Ion separator, 12. 12. ion intensity detector; MS control device, 14. CPU, 16. Memory, 17. NIST table, 18. 18. Ionization efficiency table TG device,
21. Casing, 22. Heating furnace, 23. Balance beam, 24. Gas supply,
26. Piping, 27. Temperature controller, 28. Fulcrum, 29. Sample pan, 31. sample,
32. Tilt detection sensor 33. Beam tilting device, 34. Balance beam tilting device,
36. Weight calculation device, 37. Gas exhaust port, 38. Gas transfer tube,
39. 41. ionization efficiency data table Container body, 42. Volatile substances,
43. Pinhole, 44. Lid, 46. Left column, 48. Gas transfer tube,
49. 51. electron impact ionization (EI) apparatus Ion separator, 52. Ion intensity detector, 53. MS control device, 55. Mass spectrometer, 58. Casing, 59. Ionizer, 61. Quadrupole filter, 62. Ion detector, 63. MS control device, 64. PI lamp, 65. EI device, 67. Turbomolecular pump, 68. Rotary pump, 69. Gas transport tube, G. Quantitative gas, R0. Sample chamber,
R1. Analysis room

Claims (10)

A gas obtained from a standard sample in which the abundance of the target molecule is known is ionized by soft ionization to obtain mass spectrometry data, a mass chromatogram is obtained based on the mass spectrometry data, and a peak waveform of the mass chromatogram A calibration curve creating step of obtaining a calibration curve based on the abundance and the area strength;
A gas obtained from a sample in which the abundance of the target molecule is unknown is ionized by a soft ionization process to obtain mass spectrometry data, a mass chromatogram of the molecule is obtained based on the mass analysis data, and the mass chromatogram of the mass chromatogram is obtained. An unknown sample measurement step for determining the area intensity of the peak waveform;
Obtaining the abundance of the target molecule from the area intensity obtained in the unknown sample measurement step based on the calibration curve obtained in the calibration curve creation step;
A gas quantitative analysis method comprising: A thermogravimetric process for determining the weight of a gas obtained from a sample in which the abundance of the target molecule is unknown,
The gas is ionized by soft ionization treatment to obtain mass spectrometry data, a mass chromatogram is obtained based on the mass spectrometry data, and an area intensity measurement step for obtaining an area intensity of a peak waveform of the mass chromatogram,
A quantitative gas analysis method comprising: a quantitative calculation step for obtaining an abundance of the target molecule based on the weight of the gas obtained in the thermogravimetric measurement step and the area strength obtained in the area strength measurement step . In the gas quantitative analysis method according to claim 1 or 2,
The gas quantitative analysis method, wherein the soft ionization process is a photoionization process performed using light having energy that does not generate fragment ions with respect to the target molecule. The gas quantitative analysis method according to claim 1,
Gas quantification characterized by having a step of obtaining the ionization efficiency of the target molecule from the slope of the calibration curve obtained in the calibration curve creating step, and correcting the area intensity of the peak waveform of the mass chromatogram with the ionization efficiency. Analysis method. In the gas quantitative analysis method according to claim 2,
A gas obtained from a standard sample in which the abundance of the target molecule is known is ionized by soft ionization to obtain mass spectrometry data, a mass chromatogram is obtained based on the mass spectrometry data, and a peak waveform of the mass chromatogram An area abundance-area intensity diagram is created based on the abundance and the area intensity, and the ionization efficiency of the target molecule is obtained from the slope of the abundance-area intensity diagram, and mass chromatography is performed. A gas quantitative analysis method, further comprising a step of correcting the area intensity of a peak waveform of a gram with the ionization efficiency. In the gas quantitative analysis method according to claim 4 or 5,
The gas quantitative analysis method, wherein the standard sample is a volatile sample at room temperature, and the standard sample is stored in a pinhole-equipped container. In the gas quantitative analysis method according to any one of claims 1 to 6,
A gas quantitative analysis method further comprising a qualitative analysis step of obtaining a mass spectrum from the mass spectrometry data and identifying the type of the molecule based on the mass spectrum. The gas quantitative analysis method according to claim 7, wherein
In the qualitative analysis step,
The gas is ionized by electron impact ionization to obtain a first mass spectrum,
The gas is ionized by a soft ionization process to obtain a second mass spectrum,
Obtaining the m / z value of the target molecule from the second mass spectrum,
Narrow down the output data of the reference database based on the calculated m / z value,
A gas quantitative analysis method characterized in that the target molecule is identified by comparing the narrowed output data with the first mass spectrum. (A) mass spectrometry means for ionizing gas by soft ionization treatment to generate mass spectrometry data;
(B) an area intensity calculating means for generating a mass chromatogram based on the mass spectrometry data and calculating the area intensity of the mass chromatogram;
(C) input means for inputting the abundance of the target molecule;
(D) having control means for controlling the operation of the mass analyzing means, the area intensity calculating means, and the input means,
(E) The control means has a calibration curve creation control mode and a quantitative analysis control mode,
(F) The control means includes:
(A) In the calibration curve creation control mode,
(A) The data input to the input means is stored in the storage means as the abundance of the target molecule contained in the standard sample,
(A) A calibration curve is calculated based on the stored abundance and the area intensity calculated by the area intensity calculation means, and stored in the storage means.
(B) In the quantitative analysis control mode,
(A) generating mass spectrometry data by the mass spectrometry means;
(A) The area intensity calculation means calculates the area intensity of the mass chromatogram based on the mass analysis data,
(C) A gas quantitative analysis apparatus characterized in that an abundance is calculated according to the calibration curve stored in the storage means in the calibration curve creation control mode based on the calculated area intensity. A thermogravimetric measuring means for obtaining the weight of the gas obtained from the sample;
Mass spectrometry means for ionizing gas by soft ionization processing to generate mass spectrometry data;
Mass spectrum generating means for generating a mass spectrum based on the mass spectrometry data;
Display means for displaying the mass spectrum as an image;
An area intensity calculating means for generating a mass chromatogram based on the mass spectrometry data and calculating the area intensity of the peak waveform of the mass chromatogram for each peak waveform;
Quantitative calculation means for calculating the abundance of molecules corresponding to the peak waveform based on the weight of the gas obtained by the thermogravimetric measurement means and the area intensity for each peak waveform calculated by the area intensity calculation means; ,
A gas quantitative analysis apparatus characterized by comprising:

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