JPH09236495A - Thermal analytical data processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermal analytical data processor by which a point corresponding to a firm reference as a specific threshold value is demarcated automatically and unconditionally as the starting point and the end point of a peak on the basis of the position of a vertex by a method wherein an operator instructs two arbitray points which sandwich the vertex of the peak, of an object to be analyzed, which appears in a thermal analytical curve. SOLUTION: An operator instructs two arbitrary points near both lower slopes of a peak from a thermal analytical curve S on the screen of a monitor 13 by using a mouse 15. A two-point designation point 14 designates the side of a peak starting point and the side of a peak end point. A vertex-position finding part 17 finds a peak in which an absolute value is largest from both points. Whether the vertex of the peak is at the upper part or the lower part of a line segment passing a first designation point and a second designation point is judged by a positional-relationship judgment part 18, and the peak of an endothermic operation and an exothermic operation is discriminated by an endothermic and exothermic discrimination part 19. The peak is differentiated linearly by a differential processing part 20, and the maximum value of a first differentiated value is found by a retrieval-starting-position setting part 21 so as to set a first retrieval starting position. A comparison processing part 22 compares the magnitude of the differentiated value with the magnitude of a specific threshold value. A point which is first less than the specific threshold value is demarcated by a starting- point and end-point demarcation part 23 as the starting point of the peak. The end point is demarcation in the same manner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to thermal analysis data for analyzing peaks in a thermal analysis curve obtained based on measurement data collected by a differential scanning calorimeter (DSC) or a differential thermal analyzer (DTA). The present invention relates to a processing device, and more particularly to a technique for uniquely defining a start point and an end point of a peak which is a target of analysis processing.

[0002]

2. Description of the Related Art An analysis processing of an endothermic peak or an exothermic peak in a thermal analysis curve obtained by a conventional thermal analysis data processing device based on measurement data collected in time series in a differential scanning calorimeter or a differential thermal analysis device. In the case of performing, as shown in FIG. 5, appropriate two points Q1 and Q2 are first designated near the skirt of the peak Q displayed on the monitor,
A line segment M is set between both points Q1 and Q2, while the point when the distance between the line segment M and each point Q1 and Q2 exceeds a specific threshold value set in advance is defined as a peak start point QA and an end point, respectively. The point QB is defined, and the peak Q is analyzed based on the start point QA and the end point QB. For example, the starting point QA
Then, an analysis process is performed such as calculating the area (peak area) of a shaded area surrounded by a line segment N connecting the end point QB and the thermal analysis curve S to obtain the enthalpy of the peak.

[0003]

However, in the case of the conventional thermal analysis data processing apparatus, since the starting point QA and the ending point QB are not uniquely determined, there is a problem that the reliability of the analysis result is low. That is, when designating the two points near the skirt of the peak Q necessary for defining the start point QA and the end point QB, there is no such thing as a clear reference when designating the two points, and it depends on the experience of the operator. It is done by 2
There is no guarantee that points Q1 and Q2 will be specified as points,
For example, there is no wonder that points Q1 and Q3 are designated. When the points Q1 and Q3 are designated, the start point QA and the end point Qb are defined as shown in FIG.
Compared with the case where 1 and Q2 are designated, the area between the line segment N and the line segment W is larger, and the analysis result is not constant. If the operator who handles the thermal analysis data processing device is unskilled, designation of two points becomes more unstable, and it is difficult to expect reliable analysis results.

In view of the above problems, the present invention provides a starting point of a peak to be analyzed in a thermal analysis curve, and
An object of the present invention is to provide a thermal analysis data processing device capable of defining an end point almost uniquely.

[0005]

The present invention has the following structure in order to achieve the above object. That is, the thermal analysis data processing device according to claim 1 is a thermal analysis data processing device that performs analysis processing of peaks in a thermal analysis curve obtained based on measurement data collected by a differential scanning calorimeter or a differential thermal analysis device. And (a) a data storage unit that stores the measurement data, and (b) a curve display unit that displays the thermal analysis curve on a screen of a monitor based on the measurement data stored in the data storage unit. (C)
A two-point designation unit that designates two arbitrary points sandwiching the apex of the peak to be analyzed in the thermal analysis characteristic curve being displayed on the curve display unit as a first designated point and a second designated point;
An apex position finding section for finding the position of the peak apex between the first designated point and the second designated point; and (e) heat from the apex of the peak toward the hem of the peak on the first designated point side. The differential process is performed on the analysis curve to sequentially calculate the differential value on the first designated point side, while the differential process is performed on the thermal analysis curve from the apex of the peak to the skirt of the peak on the second designated point side. And (f) a position where the absolute value of the differential value on the first designated point side is the maximum is set as the first search start position. Meanwhile, the second
A search start position setting unit that sets a position where the absolute value of the differential value on the specified point side is maximum as a second search start position,
(G) While comparing the differential value on the side of the first designated point with the specific threshold value from the first search start position, the second search position
A comparison processing unit that compares the differential value on the designated point side with a specific threshold value; and (h) a start / end point demarcation unit that demarcates the start point and end point of the peak based on the comparison result of the comparison processing unit. (I) A peak analysis processing unit that performs peak analysis processing based on the start point and the end point.

A thermal analysis data processing apparatus according to a second aspect is the thermal analysis data processing apparatus according to the first aspect,
The same position as the positional relationship determination unit that determines the positional relationship between the line segment passing through the first and second designated points designated by the two-point designation unit and the apex of the peak determined by the apex position determination unit. An endothermic / exothermic discriminating unit for discriminating whether the peak to be analyzed is an endothermic peak or an exothermic peak on the basis of the judgment result of the relation judging unit.

[0007]

The operation of the analysis processing of the peaks in the thermal analysis curve by the thermal analysis data processing apparatus of the present invention will be described below. In the thermal analysis data processing device according to the invention of claim 1, the data storage unit collects and stores the measurement data obtained in time series in the differential scanning calorimeter or the differential thermal analysis device, and then the data storage unit is displayed by the curve display unit. Display the thermal analysis curve based on the measured data on the monitor screen. Then, according to an instruction operation performed by the operator while observing the thermal analysis curve on the screen of the monitor, the two-point designation section appears at an arbitrary first designated point sandwiching the apex of the peak to be analyzed which appears in the displayed thermal analysis curve. And the second designated point are designated.

When the first designated point and the second designated point on the peak start point side and the peak end point side are designated with the apex sandwiched therebetween, the apex position determination unit causes the apex of the peak between the designated points. After obtaining the position of the thermal analysis curve, the differential processing section moves from the peak apex of the peak toward the hem of the peak on the first designated point side (the first designated point is now on the peak start point side). The differential processing is performed to sequentially calculate the differential value on the peak start point side, and the search start position setting unit determines the position where the absolute value of the differential value on the peak start point side is the maximum first.
Set as the search start position. Then, after the setting of the first search start position, the comparison processing unit performs a comparison process between the differential value on the peak start point side and a specific threshold value, and based on the comparison result of the comparison processing unit, the start / end point is calculated. A demarcation defines the starting point of the peak. Specifically, the position where the absolute value of the differential value falls below a certain value as a specific threshold value is defined as the peak start point.

Next, the differentiating processing section starts the second from the peak apex.
While performing differential processing on the thermal analysis curve toward the bottom of the peak on the specified point side (the second specified point is now the peak end point side), the differential value on the peak end point side is sequentially calculated, The search start position setting unit sets the position where the absolute value of the differential value on the peak end point side is the maximum as the second search start position. Then, after the setting of the second search start position, the comparison processing unit performs the comparison process between the differential value on the peak end point side and the specific threshold value, and based on the comparison result of the comparison processing unit, the start / end point. The demarcation portion demarcates the end point of the peak.
Specifically, the position when the absolute value of the differential value falls below a certain value as a specific threshold value is defined as the end point of the peak. Arbitrary 2 between the peak vertices as above
After performing the point pointing operation, based on the peak position of the peak that can be defined almost uniquely, the start point of the peak, and
Since they define the end points, they can be defined almost uniquely. Then, based on these demarcation results, the peak analysis processing unit executes analysis processing such as peak area calculation.

In the thermal analysis data processing apparatus according to the second aspect of the present invention, in addition to the above, the positional relationship determining unit has a line segment passing through both the first and second designated points designated by the two-point designating unit, and a vertex. While determining the positional relationship with the apex of the peak obtained by the position obtaining unit, based on this determination result, the endothermic / exothermic determination unit determines whether the peak of the analysis process is the endothermic peak or the exothermic peak. Since the determination is also performed, the subsequent analysis processing can be efficiently performed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the thermal analysis data processing apparatus of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of a differential scanning calorimeter (abbreviated as “DSC”) in which the thermal analysis data processing device according to the embodiment is used. The DSC shown in FIG. 1 includes a configuration on the detection system side for obtaining measurement data and a configuration on the data processing system side for processing the measurement data. The thermal analysis of the embodiment is provided at the configuration on the data processing system side. Data processing equipment is used. Hereinafter, a more specific description will be given.

The configuration of the detection system side of the DSC is the well-known DSC.
The reference substance holding unit 1 and the sample substance holding unit 2 are arranged in a furnace (not shown). Around the holders 1 and 2, a thermocouple 3 for detecting the temperature of the reference substance and a thermocouple 4 for detecting the temperature of the sample substance are arranged, and heat necessary for obtaining thermal analysis data is provided. Heaters 5 and 6 for generating are provided. Then, the individual output and the differential output of each thermocouple 3, 4 are sent to the AD converter 8 via the signal detector 7 that performs amplification and the like, converted into digital signals, and then sent as measurement data to the data processing system. Be done. While the detection system is actually operating,
The temperature adjusting unit 9 controls the power supplied to the heaters 5 and 6 so that the measured data is sent to the temperature adjusting unit 9 and the temperature control required for the differential thermal analysis is realized. The temperature adjusting unit 9 is composed of a CPU and RAM of a personal computer, a control program, and the like.

Next, the configuration of the data processing system side of the DSC will be described. The hard disk (data storage unit) 11 of the personal computer sequentially stores digital signals output from the AD converter 8 as measurement data in a time series manner. When the collection of the measurement data is completed, the curve display unit 12 reads out the necessary measurement data out of the measurement data stored in the hard disk (data storage unit) 11 and displays the thermal analysis curve S on the screen of the monitor 13. On the other hand, the operator uses the mouse 15 or the keyboard 16 while looking at the thermal analysis characteristic curve S to perform an instruction operation to instruct any two points sandwiching the apex of the peak to be analyzed. Upon receiving this instruction operation, the two-point designation unit 14 immediately designates the two points designated by the operator as the first designated point and the second designated point.

The apex of the peak to be analyzed is always located between the first designated point and the second designated point, and the vertex position detection unit 17 finds the peak apex between the designated points. Put out. The positional relationship determination unit 18 also determines the positional relationship between the line segment that passes through the first and second designated points designated by the two-point designation unit 14 and the peak apex determined by the vertex position determination unit 17. To do. That is, it is determined whether the apex of the peak is above (upward peak) or below (downward peak) a line segment that passes through the first and second designated points. Then, the suction / heat generation determination unit 19
Determines whether the peak to be analyzed is an endothermic peak or an exothermic peak based on the determination result of the positional relationship determination unit 18. Since the peak directions for endothermic and exothermic are different, the correspondence between peak direction and endothermic / exothermic is investigated beforehand to determine whether the peak to be analyzed is an endothermic peak or an exothermic peak. To do.

On the other hand, the differential processing section 20 performs a differential processing on the thermal analysis curve from the peak of the peak calculated by the peak position calculating section 17 toward the bottom of the peak on the side of the first designated point to perform the first differential processing.
The differential value on the specified point side is sequentially calculated. Also,
The differential processing unit 20 also performs differential processing on the thermal analysis curve from the apex of the peak toward the bottom of the peak on the second designated point side to sequentially calculate differential values on the second designated point side.

The search start position setting unit 21 sets the position where the absolute value of the differential value on the first designated point side is the maximum as the first search start position, and the absolute value of the differential value on the second designated point side. The position having the maximum value is set as the second search start position.
On the other hand, the comparison processing unit 22 determines the first search starting position and the subsequent
The differential value on the designated point side and the specific threshold value are successively compared, and the differential value on the second designated point side and the specific threshold value are successively compared after the second search start position.

As the above-mentioned differential value, a primary differential value using two or more measurement data and a secondary differential value using three or more measurement data are used. The value is used. The differential processing unit 20 may be configured to calculate a primary differential value when the search start position setting unit 21 is set and a difference value when the comparison processing unit 22 is compared.

The start / end point defining section 23 is
The position when the absolute value of the differential value on the specified point side falls below a certain numerical value as a specific threshold value is defined as the peak start point, and the absolute value of the differential value on the second specified point side is The position at the time of falling below a certain numerical value as a specific threshold value is defined as the end point of the peak. The threshold is, for example, the noise level n
Times: n is an appropriate integer), but is appropriately determined according to the thermal analysis curve S and is not limited to this. Further, the threshold value for defining the peak start point and the threshold value for defining the peak end point may be different values.

The first and second search start positions are where the slope of the peak is the largest, and the start and end points of the peak exceed the first and second search start positions toward the bottom of the peak. While it always exists where the slope is gentle,
There can be no true peak start and end points.There is a gentle slope near the peak apex that can be mistaken for the peak start and end points. There is a risk of misidentifying a position that is not a point as the start or end point of the peak. However, avoiding the vicinity of the peak apex, first, set the first and second search start positions, and from each of these toward the skirt direction of the peak, a specific threshold value corresponding to the peak start point or end point is set. In the above case, the position that is not the start point or end point of the true peak is not mistaken as the start point or end point of the peak, and the start point or end point of the peak can be defined without error. It will be possible.

Since only the maximum of the slope of the peak is searched for especially from the peak apex to the first and second search start positions, the differential value may be obtained discretely to shorten the processing time. .

The peak analysis section 24 (peak analysis processing section) executes peak analysis processing based on the peak start point and end point (that is, the peak range) thus determined. For example, the peak enthalpy is obtained by calculating the peak area, and the analysis result is output from the recording device 25 such as a printer together with the determination result of endotherm / heat generation. Of course,
Not only the peak area but also the calculation and output of the peak width, the peak height, the peak shape, the peak shift amount, etc. may be executed as necessary.

The curve display unit 12, the two-point designation unit 14, the vertex position detection unit 17, and the positional relationship determination unit 1 are included.
8, intake / heat generation determination unit 19, differentiation processing unit 20, search start position setting unit 21, comparison processing unit 22, start / end point demarcation unit 2
3, and the peak analysis unit 24 is composed of a CPU and RAM of a personal computer, a control program, and the like.

Next, the specific peak analysis processing operation by the thermal analysis data processing apparatus of the embodiment will be described with reference to FIGS.
This will be described in detail with reference to the graph showing the thermal analysis curve of FIG. 4 and the flowchart showing the flow of the analysis process in FIG.
It should be noted that the hard disk 11 on the data processing system side is assumed to have the necessary measurement data collected and stored in time series in advance by operating the detection system side of the DSC having the above configuration in advance. .

[Step F1] As shown in FIG. 2, the curve display unit 12 displays the thermal analysis curve S on the screen of the monitor 13. In FIG. 2, the horizontal axis (X axis) is the temperature (usually a constant rate of temperature rise, so is also the time), and the vertical axis (Y axis) is the specific heat (ΔH / ΔT).

[Step F2] The operator operates the mouse 1
5, the thermal analysis curve S displayed on the screen of the monitor 13
The operation of designating any two points near both skirts of the peak P in the is performed.

[Step F3] The two-point designation section 14 designates the first designated point Pa on the peak start point side and the second designated point Pb on the peak end point side based on the above support.

[Step F4] From the points on the thermal analysis curve S between the first designated point Pa and the second designated point Pb, the vertex position finding section 17 finds that the absolute value of the Y coordinate value is the maximum. When a point is obtained, this is the peak apex Pt (Xt, Yt).
Becomes

[Step F5] Positional Relation Judgment Section 18
However, the peak apex Pt is the first designated point Pa and the second designated point P.
It is determined whether the line segment C passing through b is above or below. In this example, the Y of the point R when X = Xt on the line segment C
The coordinate value Yr is compared with the coordinate value Yt of the peak apex Pt, and the lower side determination result is obtained.

[Step F6] Intake / heat generation determination section 19
However, the peak P is determined to be an endothermic peak based on the determination result that the peak apex Pt is below the line segment C. If the peak is an exothermic peak, the peak apex Pt is located above the line segment C, as shown in FIG.

[Step F7] The differential processing unit 20 goes from the peak Pt to the first designated point Pa on the peak start point side, and the primary differential value [(Yi + 1 −Yi) /
(Xi + 1-Xi)] are sequentially calculated. When the interval (Xi + 1-Xi) in the horizontal axis direction between adjacent measurement data is always the same, the difference value (Yi +
1-Yi) may be sequentially calculated. This can improve the processing speed.

[Step F8] Search Start Position Setting Section 2
1 obtains the maximum absolute value of the primary differential value and sets the first search start position Pd1.

[Step F9] First Search Start Position Pd
From 1 onward, the comparison processing unit 22 compares the absolute value of the primary differential value (which may be a difference value if the intervals between the adjacent measurement data are always equal in the horizontal axis direction) and the specific threshold value Da. Sequentially execute.

[Step F10] The start / end point demarcation unit 23 demarcates the point PA when the absolute value of the first-order differential value (or difference value) first falls below the specific threshold value Da as the peak start point PA. .

[Step F11] The differential processing unit 20 sequentially calculates the primary differential value (or difference value) on the second designated point side from the peak apex Pt toward the second designated point Pb on the peak end point side.

[Step F12] The search start position setting section 21 finds the maximum absolute value of the primary differential values and sets the second search start position Pd2.

[Step F13] First Search Start Position P
After d2, the comparison processing unit 22 sequentially executes the magnitude comparison between the absolute value of the primary differential value (or the difference value) and the specific threshold value Db.

[Step F14] The start / end point demarcation unit 23 demarcates the point PB when the absolute value of the first-order differential value (or difference value) falls below the specific threshold value Db as the peak end point PB.

As described above, since the peak start point PA and the peak end point PB are defined based on the peak apex position Pt that can be almost uniquely determined, two points arbitrarily designated (first point) Regardless of the designated position of the designated point Pa and the second designated point Pb), they can be defined almost uniquely and accurately. Therefore, even if the operator of the apparatus is an unskilled person, the analysis processing can be performed with high accuracy and reliability based on them.

[Step F15] Peak analysis processing unit 2
4 calculates the area (peak area) of the region surrounded by the line segment L passing through the peak start point PA and the peak end point PB and the thermal analysis curve S.

[Step F16] The recording unit 25 prints out that the peak P is an endothermic peak and the calculated area as the enthalpy of the peak P, and the analysis process of the peak P is completed.

The present invention is not limited to the above embodiment, but can be modified in various ways. (1) In the above embodiment, it is determined whether the peak to be analyzed is an endothermic peak or an exothermic peak, depending on whether the peak apex is above or below the line segment that passes through the first and second designated points. However, the endothermic peak / exothermic peak may be determined by a method other than this.

(2) The thermal analysis data processing apparatus of the above embodiment has been described by taking the case of processing the data measured by DSC as an example, but even in the case of processing the data measured by DTA. Good.

[0043]

According to the thermal analysis data processing apparatus of the first aspect of the present invention, if the operator indicates any two points sandwiching the peak of the peak to be analyzed which appears in the thermal analysis curve, the peak Based on the apex position, points that meet certain criteria, such as a certain threshold, are automatically defined as the start and end points of the peak, so that the start and end points of the peak can be defined almost uniquely and correctly. it can. As a result, the reliability of the analysis result can be improved.

According to the thermal analysis data processing apparatus of the second aspect of the present invention, since the peak of the analysis target is either the endothermic peak or the exothermic peak is simultaneously analyzed, the subsequent thermal analysis is performed. The processing can be performed efficiently.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a DSC according to an embodiment.

FIG. 2 is a graph showing a thermal analysis curve having an endothermic peak.

FIG. 3 is a graph showing a thermal analysis curve having an exothermic peak.

FIG. 4 is a flowchart showing a flow of peak analysis processing in the embodiment.

FIG. 5 is a graph for explaining a conventional analysis process of a peak in a thermal analysis curve.

[Explanation of symbols]

 11 ... Hard disk (data storage section) 12 ... Curve display section 13 ... Monitor 14 ... Two-point designation section 17 ... Apex position determination section 18 ... Positional relationship determination section 19 ... Intake / heat generation determination section 20 ... Differentiation processing section 21 ... Search Start position setting unit 22 ... Comparison processing unit 23 ... Start / end point demarcation unit 24 ... Peak analysis unit (peak analysis processing unit)

Claims (2)

[Claims] 1. A thermal analysis data processing device for analyzing peaks in a thermal analysis curve obtained based on measurement data collected by a differential scanning calorimeter or a differential thermal analysis device, comprising: (a) the measurement data. And (b) a curve display section for displaying the thermal analysis curve on a monitor screen based on the measurement data stored in the data storage section, and (c) a curve display section for displaying the thermal analysis curve. 2 between the peaks of the analysis target in the thermal analysis curve of
A two-point designating unit that designates a point as a first designated point and a second designated point, and (d) a vertex position finding unit that finds the position of the vertex of the peak between the first designated point and the second designated point. And (e) performing differential processing on the thermal analysis curve from the apex of the peak toward the bottom of the peak on the first designated point side to sequentially calculate the differential value on the first designated point side, while A differential processing section that performs differential processing on the thermal analysis curve from the apex of the to the skirt of the peak on the second designated point side to sequentially calculate differential values on the second designated point side, and (f) the first designated The position where the absolute value of the differential value is maximum on the point side is set as the first search start position, while the position where the absolute value of the differential value on the second designated point side is maximum is set as the second search start position. And (g) a differential value on the side of the first designated point from the first search start position and a specific value While comparing values, a comparison processing unit that compares a differential value and a specific threshold value on the second designated point side from the second search start position; and (h) a peak start point based on the comparison result of the comparison processing unit. Thermal analysis data processing, comprising: a start / end point demarcation section that demarcates the end point and an end point; and (i) a peak analysis processing section that performs peak analysis processing based on the start point and the end point. apparatus. 2. The thermal analysis data processing device according to claim 1, wherein a line segment passing through the first and second designated points designated by the two-point designation section and a vertex position determination section are determined. A positional relationship determination unit that determines the positional relationship with the apex of the peak, and an endothermic / fever that determines whether the peak of the analysis process is an endothermic peak or an exothermic peak based on the determination result of the positional relationship determination unit A thermal analysis data processing device comprising a discrimination unit.