JP2000338075A - Electrochemical analysis method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure accurate concentration even when a standard sample does not exist at a measurement place. SOLUTION: The electrochemical analysis device is equipped with a detection part 2 being brought into contact with an object to be measured such as the ozone constituent of gas or liquid and a conversion part 3 for calculating and converting a detection signal from the detection part 2, and measures constituent concentration by the conversion part using the incline of change in a current value detected by the detection part 2. In this case, a sensitivity coefficient is incorporated, where the sensitivity coefficient is calculated based on the difference between the incline of the current value at the detection part of an electrolysis diaphragm system where electrolysis liquid is included between two electrodes and concentration incline by a standard sample for calibration, and the detection value of the detection part 2 is calibrated by the sensitivity coefficient at the conversion part 3 on actual measurement for measuring the constituent concentration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for electrochemical analysis in an electrochemical analysis instrument provided with a detector for detecting the concentration of a component by electrolysis of an analyte.

[0002]

2. Description of the Related Art Conventionally, in an electrochemical analysis instrument, the concentration of a sample as a substance to be measured is measured by a detecting section and a converting section for calculating and converting a detection signal of the detecting section. The detection unit that comes into contact with the sample varies depending on the attached measuring instrument.Analysis equipment equipped with a conversion unit has a built-in measurement circuit, and after mounting a detection unit that is sensitive to the presence of the sample, calibration is performed by the detection unit of this device. Measure a gas or liquid with a known concentration of the test sample, determine the concentration gradient specific to the instrument,
Since the concentration measurement of gas or liquid in an actual room or the like is performed, it is necessary to always prepare a gas or liquid having a standard concentration at the detection location.

[0003]

However, it is difficult to always prepare a place for measuring a standard sample for calibration.
The standard sample could not be placed anywhere, and the concentration could not be easily measured. In particular, the measurement of ozone concentration, which is a problem in recent years, could not be easily prepared as a standard sample, so the number of measurement points was limited. Had to be measured by. An object of the present invention is to provide a simple electrochemical analysis capable of easily and accurately measuring an accurate component concentration without variation among analytical instruments without specifying a measurement place and without a standard sample for calibration at the measurement place. Is to provide a way. Another object of the present invention is to provide a small-sized electrochemical analyzer capable of measuring a stable and accurate concentration of a gas or liquid component as a sample without variation among instruments without a standard sample for calibration. It is to provide a device.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a detecting portion in contact with a gas or liquid substance to be measured, and a conversion for arithmetically converting a detection signal from the detecting portion. In the electrochemical analyzer that measures the component concentration in the conversion unit according to the change gradient of the current value detected by the detection unit, the standard concentration liquid or the standard calibration gas of the measurement target substance for detecting the concentration is used. The above object can be achieved by calibration in which the detection value of the detection unit can be calibrated by the conversion unit even if it does not exist.

Another object of the present invention is to provide a detecting unit which comes into contact with a substance to be measured, such as a gas or a liquid, and a converting unit for calculating and converting a detection signal from the detecting unit. In an electrochemical analyzer that measures a component concentration in a conversion unit by a gradient, a sensitivity coefficient calculated based on a difference between a gradient of a current value in the detection unit and a concentration gradient of a standard sample for calibration is incorporated, and an actual measurement is performed. This can be achieved by an electrochemical analysis method in which the detection value of the detection unit is calibrated by the sensitivity coefficient in the conversion unit to measure the component concentration.

[0006] The detection unit is of an electrolysis diaphragm type in which an electrolysis solution is interposed between two electrodes, and a sensitivity coefficient calculated based on a difference between a gradient in the detection unit and a gradient of a standard sample is transmitted to a conversion unit. The above object can be attained by an electrochemical analysis method in which a conversion value corrects a detection value of a detection unit which is input and measured and a measurement target substance detected by the detection unit is an ozone component.

Further, it has a detecting section whose current value changes in proportion to the concentration of the gas or liquid substance to be measured, and a converting section for calculating and converting a detection signal from this detecting section. In an electrochemical analyzer that measures the concentration of the substance to be measured in the conversion unit from the current value, the sensitivity coefficient calculated based on the difference between the gradient of the current value in the detection unit and the concentration gradient of the standard sample is incorporated, and the actual measurement is performed. Sometimes the detection value of the detection unit is calibrated by the sensitivity coefficient in the conversion unit to measure the component concentration, or the electrochemical analysis device, the output value of the measurement range in the detection unit is set in advance for each detection component, in the conversion unit Equivalently input and calibrate the highest output value or the lowest output value in this output value range, then measure the output value of the standard concentration liquid or standard concentration gas in the detection unit, and use the concentration value The value obtained by dividing the maximum output value or the minimum output value was calibrated by the section type to the converter as the sensitivity coefficient in the detector, the object by electrochemical analyzer instrument calibration is made possible can be achieved.

The electrochemical analyzer of the present invention can be used for measuring the concentrations of ozone, carbon monoxide, and hydrogen sulfide gas employing a diaphragm-type constant potential electrolysis method. Moreover,
It can also be used for measuring the concentration of dissolved oxygen and oxygen gas by a diaphragm galvanic or polaro electrochemical analyzer. The detection unit used in the present invention is durable and replaceable depending on the substance to be detected and measured.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrochemical analysis method of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of one embodiment of the electrochemical analysis method of the present invention. FIG. 2 is a plan view of an embodiment of the electrochemical analyzer according to the present invention.

The electrochemical analysis method of the present invention will be described. According to the electrochemical analysis method of the present invention, when the output value from the detection unit in which the current value changes according to the component concentration value in contact with the substance to be measured is converted into the concentration value by the conversion unit, the calibration value unique to the detection unit is used. It is possible to eliminate the variation of the density value for each instrument by inputting the data to the conversion unit. In particular, the calibration value input to the conversion unit is obtained by obtaining the calibration value a in the conversion unit based on the equivalent input of the lowest output value (or the highest output value) in the detection unit, and obtaining the output value of the detection unit using a standard solution or standard gas with a known concentration. b is measured, and the output value is divided by the lowest output value (highest output value) of the conversion unit to obtain a value obtained by calculating the sensitivity coefficient k. a / b = k

Reference numeral 1 denotes a main body of an electrochemical analyzer, which measures a detected value in accordance with a change in a current value due to electrolysis of a gas or liquid sample in a detecting section 2 and converts the detected value into a converting section 3
Is used to calculate the component concentration. At this time, the component concentration value can be displayed on the display unit 4 of the monitor. However, the time-dependent change may be recorded only in the recording unit, or if necessary, when the component concentration reaches a certain dangerous concentration. A warning may be issued.

As shown in FIG. 2, the output value range of the ozone concentration in the detection unit is set, and the minimum output value is inputted in the conversion unit and calibrated (a). Next, an ozone gas having a known concentration is measured by the detecting section, and the calibration coefficient a of the minimum output value is divided by the output value b to calculate a sensitivity coefficient k specific to the measuring instrument. This sensitivity coefficient is input to the conversion unit. This measuring instrument is placed in a measuring room, and the change with time of the ozone gas concentration is recorded.

There is no problem if the measured value is calibrated with the sensitivity coefficient initially set for about six months in this detector, but after the lapse of about six months, the sensitivity coefficient of the standard solution or standard gas should be reviewed again. Is more effective.

[0014]

According to the electrochemical analysis method of the present invention, accurate concentration can be measured by a small measuring instrument by a simple method without preparing a standard solution or a standard gas of a component to be detected in a narrow place such as a room. can do.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the electrochemical analysis method of the present invention.

FIG. 2 is a plan view of an embodiment of the electrochemical analyzer according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electrochemical-analysis equipment main body 2 ... Detection part 3 ... Conversion part 4 ... Display part 5 ... Adjustment mode changeover switch

Claims (6)

[Claims] A detecting section for contacting a gas or liquid substance to be measured; and a converting section for calculating and converting a detection signal from the detecting section. The converting section detects a change in current value detected by the detecting section. In an electrochemical analyzer that measures the concentration of a component by using the standard, it is necessary to be able to calibrate the detection value of the detection unit with the conversion unit even if there is no standard concentration solution or standard calibration gas of the substance to be measured for detecting the concentration. Characteristic electrochemical analysis method. And a conversion section for calculating and converting a detection signal from the detection section, wherein the conversion section detects a change in a current value detected by the detection section. In the electrochemical analyzer that measures the component concentration by using the sensitivity coefficient calculated based on the difference between the gradient of the current value in the detection unit and the concentration gradient of the calibration standard sample, the detection unit detects An electrochemical analysis method, wherein a component value is measured by calibrating a value in the conversion unit using the sensitivity coefficient. 3. The method according to claim 1, wherein the detecting section is of an electrolysis diaphragm type in which an electrolytic solution is interposed between two electrodes, and a sensitivity coefficient calculated based on a difference between a gradient in the detecting section and a gradient of a standard sample is converted. 3. The electrochemical analysis method according to claim 1, wherein the conversion unit corrects a detection value of the detection unit which is input to and measured by the conversion unit. 4. The electrochemical analysis method according to claim 1, wherein the sample detected by the detection section is an ozone component. 5. A detecting section having a current value that changes in proportion to the concentration of a gas or liquid substance to be measured, and a converting section for calculating and converting a detection signal from the detecting section. In an electrochemical analyzer that measures the concentration of a substance to be measured in a conversion unit from a current value, incorporating a sensitivity coefficient calculated based on a difference between a gradient of a current value in the detection unit and a concentration gradient of a standard sample,
An electrochemical analyzer, wherein a component value is measured by calibrating a detection value of a detection unit in a conversion unit based on the sensitivity coefficient at the time of actual measurement. 6. A detecting section having a current value that changes in proportion to the concentration of a gas or liquid substance to be measured, and a converting section for calculating and converting a detection signal from the detecting section. In an electrochemical analyzer for measuring the concentration of a substance to be measured in a conversion unit from a current value, an output value of a measurement range in the detection unit is preset for each detection component, and a maximum output of the output value range in the conversion unit is set. Calibrate by inputting the equivalent value or minimum output value, then measure the output value of the standard concentration liquid or standard concentration gas at the detection unit,
A value obtained by dividing the highest output value or the lowest output value calibrated by the conversion unit with the concentration value calibrated by the conversion unit is input to the conversion unit as a sensitivity coefficient in the detection unit, and instrument calibration can be performed. Electrochemical analyzer.