JPH03255362A - Analyzing method for sample by heating - Google Patents

Abstract

PURPOSE:To perform blank correction accurately and to improve quantitative property by storing the holding contents of the holding state in temperature rising analysis, reproducing the holding state in accordance with the contents of the memory, and performing the blank analysis. CONSTITUTION:A sample is inputted into a crucible 2 and heated, and temperature rising analysis is performed. When gas is extracted by the temperature rising in an extracting furnace 1, temperature holding is started by the signal from a control part 14, and the starting time is stored. Therefore, when a peak is judged, the temperature holding is finished, and the finished time is stored. In this way, the signal curve of the extracted gas and the change curve of the temperature in the extracting furnace are obtained. At the same time, the time data with respect to the temperature holding is obtained. Then, the same holding state as in the temperature rising analysis is reproduced without inputting the sample in the crucible 2, and the blank analysis is performed. The extracted-gas signal curve is corrected with the blank signal curve. In this way, the blank correction can be performed accurately, and the quantitative property is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for analyzing a sample by heating, in which the temperature is held based on the extracted peak of an analyte component during temperature raising analysis.

[Conventional technology]

When analyzing the extracted gas by applying electricity directly to the crucible containing the sample to heat it, the extracted gas has unique extraction characteristics (
In order to show the extraction curve (also referred to as an extraction curve), when temperature-rising analysis is performed, the temperature is held based on the extraction peak of the component to be analyzed.

By the way, in this type of sample analysis method using heating, it is necessary to perform a so-called blank analysis in which the crucible is heated without placing the sample in the crucible and the gas generated at that time is analyzed, and the blank value must be corrected. Conventionally, blank correction has been performed as follows.

That is, for example, when a crucible containing a sample is subjected to temperature raising analysis without being held using a sample analyzer having an automatic hold function, an extracted gas signal curve as shown by curve A in FIG. 3 is obtained. In addition, in this figure,
Curve B shows the change in extraction furnace temperature, and also shows the change in extraction furnace temperature, and
H, indicates the part to which hold is applied.

When quantifying the content of a predetermined element by integrating the extracted gas signals obtained by the temperature-programmed analysis, it is necessary to know the blank value. When blank analysis is performed while applying a hold, a blank signal curve as shown by curve C in FIG. 4 is obtained. In this figure, the curved line indicates the change in the temperature of the extraction furnace, and H4 indicates the part where the hold was applied.

Then, by subtracting the integrated value of the blank signal in the blank analysis from the integrated value of the extracted gas signal in the temperature-rise analysis, the content of the predetermined element can be determined.

[Problems to be Solved by the Invention] However, in the conventional method described above, as can be seen from the curve lsB in FIG. 3 and the curve in FIG. The temperature change over time in the extraction furnace is not the same in the temperature-rise analysis and the blank analysis, and therefore the peak (third peak) that occurred in the temperature-rise analysis is not the same.
It is difficult to determine whether the points (pH, Pg, P,) in the figure are generated based on the sample or as a blank, and the hold condition in blank analysis cannot be reproduced, so blank correction cannot be performed accurately. The problem was that it could not be done.

The present invention has been made with the above-mentioned considerations in mind, and its purpose is to accurately perform blank correction by reproducing the same hold state as temperature-programmed analysis in blank analysis, and to perform temperature-programmed analysis. An object of the present invention is to provide a method for analyzing a sample by heating, which can improve quantitative performance.

[Means to solve the problem]

In order to achieve the above object, the sample analysis method by heating according to the present invention memorizes the contents of the hold state in the temperature-programmed analysis, and then performs a blank analysis while reproducing the hold state according to the memory contents. The points are distinctive.

[Effect]

According to the above configuration, it is possible to reproduce the same hold state as in the temperature raising analysis in the blank analysis, and it is possible to accurately perform the blank correction.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the configuration of the main parts of a sample analysis apparatus to which the method of the present invention is applied.
An upper electrode 3.4 and a lower electrode 3.4 are provided for sandwiching and heating the electrode with electricity. 5 is an AC power source, one end of which is connected to the upper electrode 3 via an ammeter 6, and the other end connected to the lower electrode 4. 7 is a voltmeter for measuring the voltage between the picture electrodes 3.4.

Reference numeral 8 denotes a gas flow path connected to the extraction furnace 1, and a flow rate controller 9 for adjusting the flow rate of gas from the extraction furnace 1 is installed in this gas flow path.
, a room-temperature oxidizer 10 that selectively oxidizes CO in the gas and converts it into CO8, a CO8 produced in this room-temperature oxidizer lO.
CO1 remover 11 that selectively removes only H in gas
, a thermal conductivity analyzer (hereinafter referred to as TCD) 13 is connected via an HgO remover 12 that selectively removes O.
Configured to analyze hydrogen in a sample.

14 is an arithmetic control unit such as a microcomputer;
It is configured to perform arithmetic processing on the extracted gas signal from D13 to automatically hold the signal, and to store the hold status in a memory section (not shown).

In the sample analyzer having the above configuration, first, the second
A temperature increase analysis is performed as shown in the flowchart shown in Figure (A). That is, various conditions were set (step Sl
) After that, when the sample is placed in the crucible 2 and the crucible 2 is heated with electricity to start temperature-raising analysis (step S2), gas is extracted as the temperature of the extraction furnace 1 rises (step S3).
), a predetermined control signal is output from the arithmetic control section 14 to start temperature hold (step S4), and the start time elapses. (see Figure 3) is stored (step S
5).

Thereafter, after the peak is determined (step S6), a predetermined control signal is output from the calculation control section 14 to end the temperature hold (step S7), and the end time t1. (see FIG. 3) is stored (step S8).

As a result, the temperature hold start time tbs and end time Lba are stored as a pair (t
b,, the) time data is stored.

Then, it is determined whether or not the analysis has ended (step S9). If the analysis has ended, the process ends; if the analysis has not ended, the process returns to step S4, and the operations from step S4 onwards are repeated. It will be done. Therefore, in this case, an extraction gas signal curve A and an extraction furnace temperature change curve B as shown in FIG. 3 are obtained, and a plurality of pairs of time data regarding temperature hold are obtained.

Next, without putting the sample into the crucible 4, as shown in Fig. 2 (B).
Blank analysis is performed as shown in the flowchart shown in FIG. 2. At this time, blank analysis is performed while reproducing the hold state according to the memory contents (step 511). Therefore, the temperature of the extraction furnace 1 changes as shown by the curve F in FIG. By correcting the obtained extracted gas signal curve A, accurate blank correction can be performed, and quantification by form can be performed accurately.

The present invention is not limited to the above-mentioned embodiments, but can also be applied, for example, to cases in which temperature elevation analysis is performed manually.

It goes without saying that this method can also be widely applied to analyzes other than hydrogen analysis.

〔Effect of the invention〕

As explained above, in the present invention, since it is possible to reproduce the same hold state as in temperature-programmed analysis in blank analysis, blank correction can be performed accurately and the quantitative performance of this type of sample analyzer can be improved. can be significantly improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram schematically showing a sample analyzer to which the method of the present invention is applied. FIG. 2 is a flow chart showing an example of an analysis method according to the method of the present invention, in which (A) shows a temperature-rising analysis, and (B) shows a blank analysis. Figures 3 to 5 are diagrams showing the signals and temperature changes in the extraction furnace when performing sample analysis. Figure 3 shows the temperature rise analysis, and Figure 4 shows the blank analysis using the conventional method. , and FIG. 5 show blank analysis according to the method of the present invention. Figure 3

Claims (1)

[Claims] In a sample analysis method by heating in which the temperature is held based on the extracted peak of the target component during temperature programmed analysis, the contents of the hold state in the temperature programmed analysis are memorized, and then the hold state is reproduced according to the memory contents. A method for analyzing a sample by heating, characterized in that a blank analysis is performed while the sample is being heated.