JPH044543B2 - - Google Patents
Info
- Publication number
- JPH044543B2 JPH044543B2 JP3166183A JP3166183A JPH044543B2 JP H044543 B2 JPH044543 B2 JP H044543B2 JP 3166183 A JP3166183 A JP 3166183A JP 3166183 A JP3166183 A JP 3166183A JP H044543 B2 JPH044543 B2 JP H044543B2
- Authority
- JP
- Japan
- Prior art keywords
- calibration curve
- sample
- screen
- measurement
- section
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000005259 measurement Methods 0.000 claims description 23
- 238000011088 calibration curve Methods 0.000 claims description 21
- 238000000034 method Methods 0.000 claims description 18
- 238000004364 calculation method Methods 0.000 claims description 3
- 238000012360 testing method Methods 0.000 claims description 2
- 239000000523 sample Substances 0.000 description 20
- 239000000126 substance Substances 0.000 description 10
- 238000010586 diagram Methods 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000011002 quantification Methods 0.000 description 2
- 238000004445 quantitative analysis Methods 0.000 description 2
- 238000002835 absorbance Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000000538 analytical sample Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000013213 extrapolation Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/27—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands using photo-electric detection ; circuits for computing concentration
- G01N21/274—Calibration, base line adjustment, drift correction
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D18/00—Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00
- G01D18/008—Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00 with calibration coefficients stored in memory
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/3103—Atomic absorption analysis
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Indicating Measured Values (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Analysing Materials By The Use Of Radiation (AREA)
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明は標準添加法を適用し得る分析計に係
り、特に検量線をグラフ表示する表示部を備えた
分析計に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an analyzer to which a standard addition method can be applied, and more particularly to an analyzer equipped with a display section for graphically displaying a calibration curve.
標準添加法は、試料の組成が不明確で、測定時
の化学干渉あるいは物理干渉の影響を除去するこ
とが難しく、通常の検量線法では精度良く定量で
きない場合に、有効な定量法として知られてい
る。この方法はまた試料に含まれる物質の量が測
定限界程度に微量で、直接測定ではSN比が小さ
すぎて精度良く測定できない時の間接測定として
利用しても有効である。
The standard addition method is known as an effective quantitative method when the composition of the sample is unclear, it is difficult to eliminate the effects of chemical or physical interference during measurement, and accurate quantification cannot be achieved using the standard calibration curve method. ing. This method is also effective when used as an indirect measurement when the amount of a substance contained in a sample is so small that it is at the limit of measurement, and the signal-to-noise ratio is too small to measure accurately with direct measurement.
標準添加法による定量の手順を説明すると、等
量に分けられた分析試料複数個に、異なる濃度の
標準物質溶液を添加し、それぞれの溶液について
測定した後、横軸に添加した標準物質溶液の濃
度、縦軸に測定値（例えば吸光度）をとつたグラ
フ用紙上で各試料のデータをプロツトし、それら
の点を平均的に通る直線を引く。この状態を示し
たのが第１図であるが、この図において点Ａ，
Ｂ，Ｃ，Ｄが測定点であり、これらの点を平均的
に通るように引かれた直線ｌが横軸に交わる点と
原点との距離x0から試料の濃度が読み取られる。
x0はグラフ上では負の値として読み取られるが、
これを正に置き換えて求める試料の濃度とする。
また間接測定として利用する場合は、信頼性の低
い点Ａの測定を行わず、測定点Ｂ，Ｃ，Ｄから外
挿して点Ａおよび濃度x0を読み取る。 To explain the procedure for quantification using the standard addition method, standard substance solutions of different concentrations are added to multiple analytical samples divided into equal volumes, each solution is measured, and the horizontal axis shows the amount of the added standard substance solution. Plot the data for each sample on graph paper with measured values (for example, absorbance) on the vertical axis, and draw a straight line that passes through those points on average. This state is shown in Figure 1, where points A,
B, C, and D are measurement points, and the concentration of the sample is read from the distance x 0 between the origin and the point where a straight line l drawn to pass averagely through these points intersects the horizontal axis.
x 0 is read as a negative value on the graph, but
This is replaced with the positive value to obtain the concentration of the sample.
When used as an indirect measurement, point A and the concentration x 0 are read by extrapolating from measurement points B, C, and D without measuring point A, which has low reliability.
この方法は、試料毎にグラフ上に点をプロツト
して直線を引かなければならないという面倒さが
ある上に、データの点をプロツトする時、直線を
引く時、距離を読み取る時に入る誤差の個人差の
ために結果の信頼度がある程度以上高くなり得な
いという大きな欠点をもつている。さらにグラフ
の目盛の選び方によつて、プロツトされる点およ
び濃度x0の位置が変わり、精度が落ちたり、紙面
からはみ出したりするためにグラフの作り直しが
必要になる場合もある。 This method is troublesome because it requires plotting points on the graph and drawing a straight line for each sample. The major drawback is that the reliability of the results cannot be increased beyond a certain level due to the differences. Furthermore, depending on how the scale of the graph is selected, the plotted point and the position of the density x 0 may change, resulting in a loss of accuracy or the need to redraw the graph as it may extend beyond the paper.
このような欠点を改良したのが第２図に示した
検量線表示装置で、マイクロコンピユータによる
記憶・演算部とCRTによる表示部によつて構成
される。 The calibration curve display device shown in FIG. 2 is an improvement over these drawbacks, and is composed of a memory/calculation section using a microcomputer and a display section using a CRT.
第２図における定量分析の手順を説明する。ま
ず用意された各試料を順に分析計１０で測定し、
その結果をオンラインで接続された測定値入力端
子１から記憶部３に送ると共に、数値キーなどの
手段によつて濃度値入力端子２へ標準物質の添加
量を送り、相互の入力値を一対のデータとして記
憶部３に記憶させていく。全部の試料を測定し終
るまでこれを繰返し、測定終了と共に記憶部３の
データを検量線作成部５、座標軸目盛作成部４へ
送つてそれぞれ検量線、座標軸の位置および目盛
の値を決定して表示部６で合成して表示する。こ
の時の表示画面は第１図のようになる。 The procedure of quantitative analysis in FIG. 2 will be explained. First, each prepared sample was measured in order with the analyzer 10,
The results are sent to the storage unit 3 from the measured value input terminal 1 connected online, and the addition amount of the standard substance is sent to the concentration value input terminal 2 by means such as numerical keys, and the mutual input values are combined into a pair. The data is stored in the storage unit 3 as data. This is repeated until all the samples have been measured, and when the measurement is completed, the data in the storage section 3 is sent to the calibration curve creation section 5 and the coordinate axis scale creation section 4 to determine the calibration curve, coordinate axis positions, and scale values, respectively. The images are synthesized and displayed on the display unit 6. The display screen at this time will be as shown in FIG.
このような方式によれば、分析者がグラフ紙面
上にプロツトしたり直線を引く手間が省け、計算
精度や個人差の問題も解決されているが、次のよ
うな欠点が残されている。すなわち、測定試料を
全部測定した後でないと縦軸、横軸の目盛が決定
せず、グラフ化することができないため、測定の
途中に異常データが含まれていても全部の試料が
測定されてグラフ化されるまで発見できない。ま
た、測定データに従つて画面上の座標軸の位置を
決めるので、測定毎に縦軸の位置が変わり、見づ
らい。 Although this method saves the analyst the trouble of plotting on graph paper and drawing straight lines, and solves the problems of calculation accuracy and individual differences, the following drawbacks remain. In other words, the scales for the vertical and horizontal axes cannot be determined and graphed until after all the samples have been measured, so even if abnormal data is included during the measurement, all samples will not be measured. It cannot be discovered until it is graphed. Furthermore, since the position of the coordinate axes on the screen is determined according to the measurement data, the position of the vertical axis changes every time a measurement is made, making it difficult to see.
本発明の目的は、測定値をプロツトしたのと同
じ象限内で未知試料の成分濃度をグラフ表示でき
る標準添加法を適用し得る分析計を提供すること
にある。
An object of the present invention is to provide an analyzer that can apply the standard addition method and can graphically display the component concentration of an unknown sample within the same quadrant in which the measured values are plotted.
本発明は、標準物質を添加した複数試料の測定
によつて演算される検量線における外挿入部分を
反転させることにより、測定値が表示されている
象限と同じ象限内に外挿部分を画面表示すること
を特徴とする。
The present invention displays the extrapolated part on the screen in the same quadrant as the measured value by inverting the extrapolated part in the calibration curve calculated by measuring multiple samples to which standard substances have been added. It is characterized by
本発明の望ましい実施例によれば、最初に設定
された目盛（縦軸および横軸）の範囲内でグラフ
化が可能になるので各試料の測定毎に測定点を
CRTなどの表示画面上にプロツトできる。それ
故、途中での異常データの発見もやり易く、かつ
画面の広さを有効に利用できる。
According to a preferred embodiment of the present invention, graphing is possible within the initially set scale (vertical and horizontal axes), so measurement points can be set for each measurement of each sample.
It can be plotted on a display screen such as a CRT. Therefore, it is easy to discover abnormal data during the process, and the screen space can be used effectively.
本発明の望ましいのは検量線グラフの第１象限
の範囲だけを表示有効範囲として選択し、第２象
限の部分を座標軸のところから折り曲げて第１象
限の表示画面の中に同時に表示させる。このよう
にすることにより、第２象限の内容が確定する前
に座標軸を引くことができ、画面の目盛も最も添
加量の多い試料を測定した時点で決めることにな
り、最初にこの試料を測定すれば以後の試料の測
定毎に各測定点を画面上にプロツトさせることが
可能で、測定作業を能率的に行うことができる。
完成された検量線も画面の折り曲げによつて重複
部分が発生せず、求める濃度値を示す位置を座標
軸上で正の値で読み取れるので、読み取り間違い
が生じ難い。また、第１、２象限の両方を表示す
る従来の方式に比べて、プロツトされた点相互の
表示分解能が高くなる。 It is desirable in the present invention to select only the first quadrant of the calibration curve graph as the effective display range, and to display the second quadrant at the same time on the display screen of the first quadrant by folding the second quadrant from the coordinate axis. By doing this, the coordinate axes can be drawn before the contents of the second quadrant are determined, and the scale on the screen will be determined when the sample with the highest amount of addition is measured, so this sample will be measured first. Then, each measurement point can be plotted on the screen each time a sample is measured thereafter, and the measurement work can be carried out efficiently.
The completed calibration curve does not have overlapping parts due to folding of the screen, and the position indicating the desired concentration value can be read as a positive value on the coordinate axes, so reading errors are less likely to occur. Furthermore, compared to the conventional method of displaying both the first and second quadrants, the display resolution of plotted points is higher.
以下、図面によつて本発明の実施例を詳細に説
明する。 Embodiments of the present invention will be described in detail below with reference to the drawings.
第３図は本発明の一実施例を示す図である。原
子吸光光度計などの試料測定部１０からの測定値
および操作パネル１１の数値キーなどからの濃度
値が、入力端子１，２から入つて記憶部３に記憶
される。最初に測定される最も標準物質添加量の
多い試料のデータが確立した時点で、このデータ
を基に座標軸・目盛作成部４で座標軸と目盛を作
成し、その結果座標軸表示データ４１をCRTか
らなる表示部６に送つて、その時のプロツトデー
タ３１と共に表示する。その後被検成分と同種の
標準物質を添加した試料の測定が行われる毎に各
測定点を画面の中にプロツトして行き、最後のデ
ータが確立した時点で全データを検量線作成部５
に送つて、すべての点を平均的に通る直線を作
る。その検量線を反転合成部７で第２象限の部分
を第１象限の中り折り返した形に加工し、表示部
６の既にプロツトされているデータの上に重ねて
表示させる。この時の反転合成部７で作られる検
量線７１は、元の検量線の式を(1)式とした時(2)式
で与えられる。 FIG. 3 is a diagram showing an embodiment of the present invention. Measured values from a sample measuring section 10 such as an atomic absorption spectrophotometer and concentration values from numerical keys on an operation panel 11 are inputted from input terminals 1 and 2 and stored in a storage section 3 . At the point when the data of the sample to be measured with the highest addition amount of the standard substance is established, the coordinate axes and scales are created in the coordinate axis/scale creation section 4 based on this data, and as a result, the coordinate axis display data 41 is made up of the CRT. It is sent to the display unit 6 and displayed together with the plot data 31 at that time. After that, each measurement point is plotted on the screen each time a sample containing the same type of standard substance as the test component is measured, and when the final data is established, all data are transferred to the calibration curve creation section 5.
to create a straight line that passes through all points on average. The calibration curve is processed by the inversion synthesis section 7 into a shape in which the second quadrant is folded back into the first quadrant, and is displayed superimposed on the data already plotted on the display section 6. The calibration curve 71 created by the inversion synthesis section 7 at this time is given by equation (2) when the equation of the original calibration curve is defined as equation (1).
ｘ＝ay＋ｂ ……(1)
ｘ＝｜ay＋ｂ｜ ……(2)
ここでｘは濃度、ｙは測定値、ａ，ｂは係数を
示す。 x=ay+b...(1) x=|ay+b|...(2) Here, x is the concentration, y is the measured value, and a and b are coefficients.
第４図はこのようにして作成された画面の例で
ある。第４図から明らかなように、x0の値がこの
画面の範囲内で読み取れるためには点Ａの測定値
が縦軸の半分の位置より下にないといけない。こ
のことは外挿によつて求められるx0の精度を維持
する上で必要であり、一般の標準添加法における
条件とも一致する。点Ａが縦軸の上方に位置し、
x0がこの画面よりはみ出すような場合には目盛を
修正して再プロツトするのでなく、標準物質の添
加量を増した試料を作り直して測定をやり直す。
このように本実施例によれば先にあげた特徴を有
する上に添加量の適否の判断が測定の途中で適格
にでき、無駄な測定を回避することの可能な標準
添加法用の検量線表示ができる。 FIG. 4 is an example of a screen created in this way. As is clear from FIG. 4, in order for the value of x 0 to be read within the range of this screen, the measured value at point A must be below the halfway position on the vertical axis. This is necessary to maintain the accuracy of x 0 determined by extrapolation, and also coincides with the conditions in the general standard addition method. Point A is located above the vertical axis,
If x 0 extends beyond this screen, instead of correcting the scale and replotting, create a sample with an increased amount of the standard substance added and redo the measurement.
As described above, according to this example, in addition to having the above-mentioned characteristics, the calibration curve for the standard addition method can be used to judge the appropriateness of the addition amount during the measurement, and can avoid unnecessary measurements. Can be displayed.
第５図はマイクロコンピユータを用いて検量線
を作成する場合の実施例の動作フローを示す図で
ある。 FIG. 5 is a diagram showing the operational flow of an embodiment in which a calibration curve is created using a microcomputer.
〔発明の効果〕
以上の説明から理解されるように、本発明によ
れば、標準物質を添加した試料の測定値を画面上
にプロツトしたのと同じ象限内で、未知試料の成
分濃度をグラフ表示できるので、測定の都度画面
上のグラフの横軸又は縦軸を移動させなくても標
準添加法の検量線の作成が可能となる。[Effects of the Invention] As can be understood from the above explanation, according to the present invention, the component concentration of an unknown sample can be plotted on the screen in the same quadrant as the measured value of the sample to which the standard substance has been added. Since it can be displayed, it is possible to create a calibration curve for the standard addition method without having to move the horizontal or vertical axes of the graph on the screen each time a measurement is performed.
第１図は従来の標準添加法を説明するための
図、第２図は第１図の方法をCRT画面上で実行
する場合に予想される図、第３図は本発明の一実
施例を説明するための図、第４図は実施例の
CRT画面上に表示される検量線例を示す図、第
５図は検量線を画面表示する場合の動作フロー図
である。
３……記憶部、４……座標軸・目盛作成部、５
……検量線作成部、６……表示部、７……反転合
成部、１０……試料測定部、x0……横軸上の交点
から原点までの距離。
Figure 1 is a diagram for explaining the conventional standard addition method, Figure 2 is a diagram that would be expected when the method in Figure 1 is executed on a CRT screen, and Figure 3 is an illustration of an embodiment of the present invention. A diagram for explanation, FIG. 4 is an example of the embodiment.
FIG. 5, which is a diagram showing an example of a calibration curve displayed on a CRT screen, is an operation flowchart when displaying a calibration curve on a screen. 3...Storage unit, 4...Coordinate axis/scale creation unit, 5
...Calibration curve creation section, 6... Display section, 7... Inversion synthesis section, 10... Sample measurement section, x 0 ... Distance from the intersection on the horizontal axis to the origin.
Claims (1)
被検成分の測定値に基づいて検量線を演算する演
算部と、濃度値と複数の測定値の関係を検量線と
して画面上にグラフ表示する表示部とを備えた標
準添加法を適用し得る分析計において、上記検量
線の外挿部分を反転させ、測定値が表示されてい
る象限と同じ象限内に外挿部分を表示せしめるよ
うに上記表示部に信号を入力する手段を設けたこ
とを特徴とする標準添加法を適用し得る分析計。1 A sample measurement section, a calculation section that calculates a calibration curve based on the measured values of the test components of the sample from this sample measurement section, and a graph displaying the relationship between the concentration value and multiple measured values as a calibration curve on the screen. In an analyzer capable of applying the standard addition method, the extrapolated portion of the calibration curve is inverted and the extrapolated portion is displayed in the same quadrant as the measured value is displayed. An analyzer to which the standard addition method can be applied, characterized in that the display section is provided with means for inputting a signal.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3166183A JPS59157538A (en) | 1983-02-25 | 1983-02-25 | Analyzer applicable with standard adding method |
| DE19843406223 DE3406223A1 (en) | 1983-02-25 | 1984-02-21 | Analyser for the standard addition method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3166183A JPS59157538A (en) | 1983-02-25 | 1983-02-25 | Analyzer applicable with standard adding method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59157538A JPS59157538A (en) | 1984-09-06 |
| JPH044543B2 true JPH044543B2 (en) | 1992-01-28 |
Family
ID=12337325
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3166183A Granted JPS59157538A (en) | 1983-02-25 | 1983-02-25 | Analyzer applicable with standard adding method |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPS59157538A (en) |
| DE (1) | DE3406223A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3439761A1 (en) * | 1984-10-31 | 1986-05-07 | Klaus-Peter 6800 Mannheim Becker | METHOD FOR DETERMINING ENDOTOXIN CONCENTRATIONS |
| GB2243211A (en) * | 1990-04-20 | 1991-10-23 | Philips Electronic Associated | Analytical instrument and method of calibrating an analytical instrument |
| DE19610855A1 (en) * | 1996-03-07 | 1997-09-11 | Geesthacht Gkss Forschung | Calibrating units analysing chemical elements and/or compounds in solutions/liquid mixtures |
| DE102014106916A1 (en) | 2013-05-28 | 2014-12-04 | Endress + Hauser Conducta Gesellschaft für Mess- und Regeltechnik mbH + Co. KG | Device for the automated determination of at least two different process parameters |
| KR101999260B1 (en) * | 2016-09-30 | 2019-07-12 | 삼성전자주식회사 | Specimen analysis apparatus, and method for measuring thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3912456A (en) * | 1974-03-04 | 1975-10-14 | Anatronics Corp | Apparatus and method for automatic chemical analysis |
| US3909203A (en) * | 1974-08-04 | 1975-09-30 | Anatronics Corp | Analysis system having random identification and labeling system |
-
1983
- 1983-02-25 JP JP3166183A patent/JPS59157538A/en active Granted
-
1984
- 1984-02-21 DE DE19843406223 patent/DE3406223A1/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| DE3406223A1 (en) | 1984-08-30 |
| JPS59157538A (en) | 1984-09-06 |
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