JPH11148914A - Apparatus for measuring concentration of chlorine - Google Patents
Apparatus for measuring concentration of chlorineInfo
- Publication number
- JPH11148914A JPH11148914A JP9315724A JP31572497A JPH11148914A JP H11148914 A JPH11148914 A JP H11148914A JP 9315724 A JP9315724 A JP 9315724A JP 31572497 A JP31572497 A JP 31572497A JP H11148914 A JPH11148914 A JP H11148914A
- Authority
- JP
- Japan
- Prior art keywords
- chlorine
- concentration
- electrode
- measured
- free chlorine
- 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.)
- Granted
Links
Landscapes
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は塩素濃度測定装置に
関し、特に水道水中に含まれる遊離塩素の濃度を測定す
るための塩素濃度測定装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chlorine concentration measuring device, and more particularly to a chlorine concentration measuring device for measuring the concentration of free chlorine contained in tap water.
【０００２】[0002]
【従来の技術】塩素ガスを水に溶かすと、加水分解によ
り次亜塩素酸（ＨＯＣｌ）や次亜塩素酸イオン（ＯＣｌ
- ）が生じる。これらは遊離塩素と呼ばれ、消毒作用を
果たす。このうち次亜塩素酸は、水にアンモニア性窒素
（ＮＨ3 Ｎ）が含まれると、これと反応してクロラミン
（結合塩素）を作る。この結合塩素は遊離塩素よりも消
毒作用が弱いため、水道水の消毒効果を管理する際に
は、遊離塩素と結合塩素とを区別して把握すなわち測定
しなければならない。2. Description of the Related Art When chlorine gas is dissolved in water, it is hydrolyzed to form hypochlorous acid (HOCl) or hypochlorite ion (OCl).
- ) Occurs. These are called free chlorine and perform a disinfecting action. Of these, hypochlorous acid reacts with ammonia nitrogen (NH 3 N) when it contains water to form chloramine (bound chlorine). Since this combined chlorine has a weaker disinfecting action than free chlorine, when controlling the disinfecting effect of tap water, free chlorine and bound chlorine must be distinguished and measured.
【０００３】従来において、遊離塩素の測定装置として
は、検出極に金電極を用いた回転電極型のポーラログラ
フ式の遊離塩素計が多用されている。しかし、このよう
な従来の測定装置では、測定対象中に遊離塩素の他に結
合塩素が共存する場合に、遊離塩素の測定に正の誤差を
与える。これは、検出極に金電極を用いたときに、遊離
塩素の測定のために印加する電圧により結合塩素も還元
され、これによって電流が発生するためである。Heretofore, as a free chlorine measuring device, a polarographic free chlorine meter of a rotating electrode type using a gold electrode as a detection electrode has been frequently used. However, such a conventional measuring apparatus gives a positive error to the measurement of free chlorine when bound chlorine is present together with free chlorine in the measurement object. This is because when a gold electrode is used as the detection electrode, the combined chlorine is also reduced by the voltage applied for measuring free chlorine, and a current is thereby generated.
【０００４】このような結合塩素の影響を除去するため
に、試薬を添加しながら測定する装置も知られている。
しかし、試薬の管理や補充などのメンテナンス性が悪い
という欠点がある。[0004] In order to eliminate the influence of such bound chlorine, there is also known an apparatus which measures while adding a reagent.
However, there is a drawback that the maintainability such as management and replenishment of reagents is poor.
【０００５】そこで、無試薬で結合塩素の影響を除去し
ようとしたものが、たとえば実開平５−４３０６４号公
報や特開平８−２７８２８２号公報において提案されて
いる。[0005] In order to eliminate the influence of bound chlorine without using a reagent, Japanese Patent Application Laid-Open No. Hei 5-43064 and Japanese Patent Application Laid-Open No. Hei 8-278282 have proposed such a method.
【０００６】このうち、実開平５−４３０６４号公報に
おいて提案されているものは、検出極に金と白金とを主
成分とする合金を用いることで、遊離塩素の測定の際に
おける結合塩素の影響を軽減させようとしたものであ
る。[0006] Of these, the one proposed in Japanese Utility Model Application Laid-Open No. 5-43064 discloses that the use of an alloy mainly composed of gold and platinum for the detection electrode allows the influence of bound chlorine on the measurement of free chlorine. It is intended to alleviate this.
【０００７】また、特開平８−２７８２８２号公報にお
いて提案されているものは、検出極を白金電極とすると
ともに対極を銀／塩化銀電極とすることで、結合塩素の
影響の少ない領域でポーラログラムを得ようとしたもの
である。Japanese Patent Application Laid-Open No. Hei 8-278282 proposes a polarogram in a region where the effect of bound chlorine is small by using a platinum electrode as a detection electrode and a silver / silver chloride electrode as a counter electrode. It was intended to obtain.
【０００８】[0008]
【発明が解決しようとする課題】しかし、これら実開平
５−４３０６４号公報や特開平８−２７８２８２号公報
において提案されているものでは、遊離塩素の測定精度
が必ずしも満足なものではないという問題点がある。However, those proposed in Japanese Unexamined Utility Model Publication No. Hei 5-43064 and Japanese Unexamined Patent Publication No. Hei 8-278282 have a problem that the measurement accuracy of free chlorine is not always satisfactory. There is.
【０００９】そこで本発明は、このような問題点を解決
して、遊離塩素の濃度を精度良く測定できるようにする
ことを目的とする。Accordingly, an object of the present invention is to solve such a problem and to enable the concentration of free chlorine to be accurately measured.
【００１０】[0010]
【課題を解決するための手段】この目的を達成するため
本発明は、被測定液に浸漬された検出極と対極との間に
電圧を印加して、これら電極間に流れる電流から被測定
液中の遊離塩素濃度を測定するようにした装置が、結合
塩素に対する感度の異なる二つの検出極を有するととも
に、各々の検出極で得られた電流からそれぞれの電流に
含まれる結合塩素の影響分どうしを相殺して遊離塩素の
濃度を求める手段を有するようにしたものである。In order to achieve this object, the present invention provides a method for applying a voltage between a detection electrode immersed in a liquid to be measured and a counter electrode, and applying a voltage between the electrodes to the liquid to be measured. A device that measures the concentration of free chlorine in air has two detection poles with different sensitivities to bound chlorine, and separates the influence of bound chlorine contained in each current from the current obtained at each detection pole. In order to obtain a concentration of free chlorine.
【００１１】このような構成であると、結合塩素に対す
る感度の異なる二つの検出極の各々で得られた電流か
ら、それぞれの電流に含まれる結合塩素の影響分どうし
を相殺して、遊離塩素の濃度を求めるものであるため、
測定結果から結合塩素の影響が確実に取り除かれ、した
がって遊離塩素の濃度が精度良く測定される。With such a configuration, the influence of the bound chlorine contained in each of the currents is offset from the current obtained at each of the two detection electrodes having different sensitivities to the bound chlorine. Because it is for obtaining the concentration,
The effect of bound chlorine is reliably removed from the measurement result, and thus the concentration of free chlorine is measured with high accuracy.
【００１２】[0012]
【発明の実施の形態】図１において、１１は遊離塩素計
で、被測定液Ｓを貯留する測定槽１２を有する。この測
定槽１２には、被測定液Ｓを導入するための導入口１３
と、測定済の被測定液Ｓを排出するための排出口１４と
が設けられている。１５は回転電極で、その先端の検出
部１６が被測定液Ｓの中に浸漬されるとともに、モータ
１７によって回転されるように構成されている。１８は
対極で、銀／塩化銀電極によって構成されている。DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 11 denotes a free chlorine meter, which has a measuring tank 12 for storing a liquid S to be measured. The measuring tank 12 has an inlet 13 for introducing the liquid S to be measured.
And a discharge port 14 for discharging the measured liquid S having been measured. Reference numeral 15 denotes a rotating electrode, which is configured so that a detection unit 16 at the tip thereof is immersed in the liquid S to be measured and is rotated by a motor 17. Reference numeral 18 denotes a counter electrode, which is constituted by a silver / silver chloride electrode.
【００１３】図２に拡大して示すように、検出部１６に
は、金電極２０と、白金電極２１とが、互いに電気的に
絶縁された状態で設けられている。これら金電極２０お
よび白金電極２１からの各々の出力ライン２２、２３
は、図１に示すように、それぞれ、電流−電圧変換器２
４と増幅器２５とを介して、演算処理回路２６へ導かれ
ている。２７は金電極電圧読取器、２８は金電極電位設
定器、２９は白金電極電圧読取器、３０は白金電極電位
設定器である。As shown in FIG. 2 in an enlarged manner, a gold electrode 20 and a platinum electrode 21 are provided in the detecting section 16 in a state of being electrically insulated from each other. Output lines 22, 23 from the gold electrode 20 and the platinum electrode 21, respectively.
Are current-to-voltage converters 2 as shown in FIG.
4 and an amplifier 25, and are led to an arithmetic processing circuit 26. 27 is a gold electrode voltage reader, 28 is a gold electrode potential setter, 29 is a platinum electrode voltage reader, and 30 is a platinum electrode potential setter.
【００１４】図３は、金電極２０と白金電極２１とにつ
いての、結合塩素濃度の変化に対する還元電流値の変化
の様子すなわち感度を比較したものである。図示のよう
に、結合塩素に対する感度は検出電極の材質によって異
なる。FIG. 3 shows a comparison of the change in the reduction current value, that is, the sensitivity, of the gold electrode 20 and the platinum electrode 21 with respect to the change in the concentration of bound chlorine. As shown in the figure, the sensitivity to bound chlorine differs depending on the material of the detection electrode.
【００１５】本発明においては、上述のようにこれらの
電極２０、２１を同一の測定槽１２内に配置し、各々の
電極２０、２１により得られる還元電流値から、それぞ
れの電流に含まれる結合塩素の影響分どうしを相殺する
ことで、遊離塩素の濃度を求める。In the present invention, as described above, these electrodes 20 and 21 are arranged in the same measuring tank 12, and the reduction current value obtained by each of the electrodes 20 and 21 is used to determine the coupling included in each current. The concentration of free chlorine is determined by offsetting the effects of chlorine.
【００１６】すなわち、各電極２０、２１に流れる電流
は、次式で表される。 ＩAu＝ａＦ＋ｂＣ ………（１） ＩPt＝ｃＦ＋ｄＣ ………（２） ここで、ＩAuは金電極２０に流れる電流、ＩPtは白金電
極２１に流れる電流、Ｆは遊離塩素濃度、Ｃは結合塩素
濃度である。また、ａは金電極２０の遊離塩素に対する
感度、ｂは金電極２０の結合塩素に対する感度、ｃは白
金電極２１の遊離塩素に対する感度、ｄは白金電極２１
の結合塩素に対する感度で、これらは各電極に固有の定
数である。That is, the current flowing through each of the electrodes 20 and 21 is expressed by the following equation. I Au = aF + bC (1) I Pt = cF + dC (2) where I Au is the current flowing through the gold electrode 20, I Pt is the current flowing through the platinum electrode 21, F is the free chlorine concentration, Is the bound chlorine concentration. A is the sensitivity of the gold electrode 20 to free chlorine, b is the sensitivity of the gold electrode 20 to bound chlorine, c is the sensitivity of the platinum electrode 21 to free chlorine, and d is the sensitivity of the platinum electrode 21 to free chlorine.
, Which are intrinsic constants of each electrode.
【００１７】上記の（１）式と（２）式とを連立方程式
として、結合塩素濃度Ｃを消去すれば、遊離塩素濃度Ｆ
を、金電極２０に流れる電流ＩAuと白金電極２１に流れ
る電流ＩPtとによって、次式から求めることができる。If the combined chlorine concentration C is eliminated by using the above equations (1) and (2) as simultaneous equations, the free chlorine concentration F
From the current I Au flowing through the gold electrode 20 and the current I Pt flowing through the platinum electrode 21 from the following equation.
【００１８】 Ｆ＝（ｄＩAu−ｂＩPt）／（ａｄ−ｂｃ） ………（３） 次に、図４〜図６にもとづき、本発明の装置と従来装置
とによる比較試験の結果について説明する。なお、従来
装置としては、検出極に金電極を用いた回転電極型のポ
ーラログラフ式遊離塩素計を用いた。F = (dI Au −bI Pt ) / (ad−bc) (3) Next, based on FIGS. 4 to 6, the results of a comparison test between the apparatus of the present invention and the conventional apparatus will be described. I do. In addition, as a conventional apparatus, a rotating electrode type polarographic free chlorine meter using a gold electrode as a detection electrode was used.
【００１９】図４は、試験の対象とした多数の被測定液
についての、遊離塩素濃度と結合塩素濃度との関係を示
す。これらの被測定液について本発明の装置と従来装置
とによって測定したときの装置指示値を図５に示す。図
５に示すように、従来装置では、本発明の装置に比べて
大きな測定誤差が生じている。図６は、被測定液におけ
る結合塩素の濃度と測定誤差との関係を示す。この図６
から、本発明の装置では結合塩素の濃度の大小にかかわ
らず測定誤差はある一定の小さな範囲内におさまってい
るが、従来装置では、測定誤差が結合塩素の濃度に大き
く影響を受けていることが判る。FIG. 4 shows the relationship between the free chlorine concentration and the bound chlorine concentration for a large number of test liquids to be tested. FIG. 5 shows device readings when these liquids to be measured were measured by the device of the present invention and the conventional device. As shown in FIG. 5, the conventional device has a larger measurement error than the device of the present invention. FIG. 6 shows the relationship between the concentration of bound chlorine in the liquid to be measured and the measurement error. This figure 6
Therefore, in the apparatus of the present invention, the measurement error is within a certain small range irrespective of the magnitude of the concentration of the combined chlorine, but in the conventional apparatus, the measurement error is greatly affected by the concentration of the combined chlorine. I understand.
【００２０】なお、上記においては遊離塩素の濃度を測
定する場合について説明したが、上記の（１）式と
（２）式とを連立方程式として、反対に遊離塩素濃度Ｆ
を消去すれば、結合塩素濃度Ｃを求めることもでき、本
発明の装置を結合塩素の測定装置として利用することも
できる。Although the case where the concentration of free chlorine is measured has been described above, the above-mentioned equations (1) and (2) are used as simultaneous equations, and conversely, the free chlorine concentration F
Is eliminated, the combined chlorine concentration C can be obtained, and the apparatus of the present invention can be used as a combined chlorine measuring apparatus.
【００２１】[0021]
【発明の効果】以上のように本発明によると、結合塩素
に対する感度の異なる二つの検出極を有するとともに、
各々の検出極で得られた電流からそれぞれの電流に含ま
れる結合塩素の影響分どうしを相殺して遊離塩素の濃度
を求める手段を有するようにしたため、測定結果から結
合塩素の影響を確実に除去でき、したがって遊離塩素の
濃度を精度良く測定することができる。As described above, according to the present invention, two detection electrodes having different sensitivities to bound chlorine are provided,
There is a means to obtain the concentration of free chlorine by canceling out the effect of bound chlorine contained in each current from the current obtained at each detection electrode, so that the effect of bound chlorine is reliably removed from the measurement results. Therefore, the concentration of free chlorine can be accurately measured.
【図１】本発明の実施の形態の塩素濃度測定装置の概略
構成を示す図である。FIG. 1 is a diagram showing a schematic configuration of a chlorine concentration measuring device according to an embodiment of the present invention.
【図２】図１における回転電極の検出部を拡大して示す
図である。FIG. 2 is an enlarged view showing a detection unit of a rotating electrode in FIG. 1;
【図３】図１の装置における金電極と白金電極とについ
ての、結合塩素濃度の変化に対する感度の比較結果を示
す図である。FIG. 3 is a view showing a comparison result of sensitivities of a gold electrode and a platinum electrode in the apparatus of FIG.
【図４】試験の対象とした多数の被測定液についての、
遊離塩素濃度と結合塩素濃度との関係を示す図である。FIG. 4 shows the results for a number of test liquids to be tested.
It is a figure which shows the relationship between a free chlorine concentration and a combined chlorine concentration.
【図５】図４の被測定液について本発明の装置と従来装
置とによって測定したときの装置指示値を示す図であ
る。FIG. 5 is a diagram showing device indicated values when the liquid to be measured in FIG. 4 is measured by the device of the present invention and a conventional device.
【図６】本発明の装置と従来装置とについての、被測定
液における結合塩素の濃度と測定誤差との関係を示す図
である。FIG. 6 is a diagram showing the relationship between the concentration of bound chlorine in the liquid to be measured and the measurement error for the apparatus of the present invention and the conventional apparatus.
１５ 回転電極 １６ 検出部 ２０ 金電極 ２１ 白金電極 ２６ 演算処理回路 15 Rotating electrode 16 Detector 20 Gold electrode 21 Platinum electrode 26 Arithmetic processing circuit
───────────────────────────────────────────────────── フロントページの続き (72)発明者 浪川 憲二郎 兵庫県尼崎市大浜町２丁目26番地 株式会 社クボタ武庫川製造所内 (72)発明者 安達 徹 兵庫県尼崎市大浜町２丁目26番地 株式会 社クボタ武庫川製造所内 (72)発明者 瀬渡 長武 京都府京都市南区吉祥院新田二の段町68 京都電子工業株式会社内 (72)発明者 清水 俊之 京都府京都市南区吉祥院新田二の段町68 京都電子工業株式会社内 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kenjiro Namikawa 2-26-Ohama-cho, Amagasaki-shi, Hyogo Pref. Inside the Kubota-Mukogawa Works (72) Inventor Tohru Adachi 2-26-Ohama-cho, Amagasaki-shi, Hyogo Stock Association Inside the Kubota Mukogawa Works (72) Inventor Nagatake Seto 68 Nitta-Nancho, Kichijoin, Minami-ku, Kyoto, Kyoto Inside Kyoto Electronics Industry Co., Ltd. (72) Inventor Toshiyuki Shimizu, Kichijoin Nitta, Minami-ku, Kyoto, Kyoto Ninodancho 68 Kyoto Electronics Industry Co., Ltd.
Claims (1)
間に電圧を印加して、これら電極間に流れる電流から被
測定液中の遊離塩素濃度を測定するようにした装置であ
って、結合塩素に対する感度の異なる二つの検出極を有
するとともに、各々の検出極で得られた電流からそれぞ
れの電流に含まれる結合塩素の影響分どうしを相殺して
遊離塩素の濃度を求める手段を有することを特徴とする
塩素濃度測定装置。An apparatus for applying a voltage between a detection electrode and a counter electrode immersed in a liquid to be measured and measuring the concentration of free chlorine in the liquid to be measured from a current flowing between these electrodes. Means having two detection poles having different sensitivities to bound chlorine, and a means for obtaining the concentration of free chlorine by canceling out the influence of the bound chlorine contained in each current from the current obtained at each detection pole. A chlorine concentration measuring device comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31572497A JP3459168B2 (en) | 1997-11-18 | 1997-11-18 | Chlorine concentration measurement device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31572497A JP3459168B2 (en) | 1997-11-18 | 1997-11-18 | Chlorine concentration measurement device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH11148914A true JPH11148914A (en) | 1999-06-02 |
| JP3459168B2 JP3459168B2 (en) | 2003-10-20 |
Family
ID=18068777
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31572497A Expired - Fee Related JP3459168B2 (en) | 1997-11-18 | 1997-11-18 | Chlorine concentration measurement device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3459168B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002090339A (en) * | 2000-09-20 | 2002-03-27 | Dkk Toa Corp | Sensor for oxidation-reduction electric current measuring instrument, oxidation-reduction electric current measuring instrument, and method and system using the instrument for controlling water quality |
| JP2006317229A (en) * | 2005-05-11 | 2006-11-24 | Nikken System Kk | Continuous monitoring method of water quality |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0298661A (en) * | 1988-10-05 | 1990-04-11 | Yokogawa Electric Corp | Method for measuring residual chlorine without being affected by disturbing component |
| JPH02154142A (en) * | 1988-12-06 | 1990-06-13 | Yokogawa Electric Corp | Residual chlorine meter with bound chlorine monitoring function |
| JPH09178699A (en) * | 1995-12-28 | 1997-07-11 | Kubota Corp | Method and device for measuring residual chlorine |
| JPH1082761A (en) * | 1996-09-05 | 1998-03-31 | Merusu Giken:Kk | Method and apparatus for measuring residual chlorine, and probe for detecting residual chlorine |
| JPH11148915A (en) * | 1997-11-18 | 1999-06-02 | Kubota Corp | Apparatus for measuring concentration of chlorine |
-
1997
- 1997-11-18 JP JP31572497A patent/JP3459168B2/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0298661A (en) * | 1988-10-05 | 1990-04-11 | Yokogawa Electric Corp | Method for measuring residual chlorine without being affected by disturbing component |
| JPH02154142A (en) * | 1988-12-06 | 1990-06-13 | Yokogawa Electric Corp | Residual chlorine meter with bound chlorine monitoring function |
| JPH09178699A (en) * | 1995-12-28 | 1997-07-11 | Kubota Corp | Method and device for measuring residual chlorine |
| JPH1082761A (en) * | 1996-09-05 | 1998-03-31 | Merusu Giken:Kk | Method and apparatus for measuring residual chlorine, and probe for detecting residual chlorine |
| JPH11148915A (en) * | 1997-11-18 | 1999-06-02 | Kubota Corp | Apparatus for measuring concentration of chlorine |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002090339A (en) * | 2000-09-20 | 2002-03-27 | Dkk Toa Corp | Sensor for oxidation-reduction electric current measuring instrument, oxidation-reduction electric current measuring instrument, and method and system using the instrument for controlling water quality |
| JP2006317229A (en) * | 2005-05-11 | 2006-11-24 | Nikken System Kk | Continuous monitoring method of water quality |
| JP4652119B2 (en) * | 2005-05-11 | 2011-03-16 | 日研システム株式会社 | Water quality continuous monitoring method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3459168B2 (en) | 2003-10-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9207204B2 (en) | Method and apparatus for determining information concerning presence of constituents of a liquid sample with oxygen demand | |
| US3413199A (en) | Method for measurement of residual chlorine or the like | |
| US4400242A (en) | Electrochemical method of determining oxygen, halothane and nitrous oxide | |
| EP1788382A1 (en) | Electrochemical residual chlorine measuring method and device with a doped diamond working electrode | |
| US7323091B1 (en) | Multimode electrochemical sensing array | |
| JP4463405B2 (en) | Sensor for redox current measuring device and redox current measuring device | |
| US7087150B2 (en) | Chloramine amperometric sensor | |
| JP3361237B2 (en) | Residual chlorine measuring method and apparatus and residual chlorine detecting probe | |
| WO2009055093A1 (en) | Electrochemical methods for selective detection of free chlorine, monochloramine and dichloramine | |
| US5316648A (en) | Electrochemical measuring cell for detecting gases and vapors | |
| JP3459168B2 (en) | Chlorine concentration measurement device | |
| JP3504127B2 (en) | Chlorine concentration measuring device | |
| JP3354054B2 (en) | Residual chlorine meter | |
| JP7231814B2 (en) | Calibration method of residual chlorine measuring device | |
| JP3654694B2 (en) | Residual chlorine measuring method and residual chlorine meter | |
| EP3472597B1 (en) | A method for measuring the concentration of a chemical species using a reagent baseline | |
| JPH1123534A (en) | Method and device for measuring hypochlorous acid | |
| JPS61176846A (en) | Ion sensor body | |
| US4741815A (en) | Apparatus for indication of the final stage of a titration analysis | |
| JPH0635959B2 (en) | Residual chlorine measurement method not affected by interfering components | |
| JPH07253409A (en) | Selectivity coefficient measuring method | |
| JP4322555B2 (en) | Residual chlorine concentration measuring method and residual chlorine concentration measuring device | |
| JPH0635952B2 (en) | Residual chlorine meter with combined chlorine monitor function | |
| JP3076384B2 (en) | Ion concentration analyzer | |
| JPS6243134B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080808 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090808 Year of fee payment: 6 |
|
| LAPS | Cancellation because of no payment of annual fees |