JP3342216B2 - Method for determining total nitrogen in liquid samples - Google Patents
Method for determining total nitrogen in liquid samplesInfo
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- JP3342216B2 JP3342216B2 JP33860594A JP33860594A JP3342216B2 JP 3342216 B2 JP3342216 B2 JP 3342216B2 JP 33860594 A JP33860594 A JP 33860594A JP 33860594 A JP33860594 A JP 33860594A JP 3342216 B2 JP3342216 B2 JP 3342216B2
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Description
【０００１】[0001]
【産業上の利用分野】この発明は、液体試料中の全窒素
定量方法に関し、特に、全窒素測定時の臭素の妨害影響
を補正した液体試料中の全窒素定量方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining total nitrogen in a liquid sample, and more particularly, to a method for determining total nitrogen in a liquid sample in which the influence of bromine during the measurement of total nitrogen is corrected.
【０００２】水中の窒素化合物は、水域の富栄養化と深
く関連することから、これに対する規制が行われてお
り、海水や湖沼について全窒素としての環境標準値が定
められている。そして、全窒素の測定方法は、ＪＩＳＫ
０１０２に各種規定されている。[0002] Nitrogen compounds in water are closely related to eutrophication of water bodies, and are therefore regulated, and environmental standard values of total nitrogen for seawater and lakes have been determined. And the measuring method of total nitrogen is JISK
0102.
【０００３】[0003]
【発明が解決しようとする課題】前記ＪＩＳＫ０１０２
に規定されている紫外線吸光光度法は、最も簡便で多く
の自動計測器に採用されているが、１０ｍｇ／ｌ以上の
臭素の妨害を受けるため、この方法を臭素濃度が約７０
ｍｇ／ｌである海水の測定には適用が不可能である。ま
た、ＪＩＳＫ０１０２に規定されている他の方法は、臭
素の影響を受けないが、測定に２時間といった長時間を
要したり、有害廃液が出るなど、自動計測器への適用は
困難である。The above-mentioned JIS K0102
The ultraviolet absorption spectrophotometry method specified in the above is the simplest method and is adopted for many automatic measuring instruments. However, since it is hindered by bromine of 10 mg / l or more, this method is used when the bromine concentration is about 70%.
It is not applicable for the measurement of seawater of mg / l. The other method specified in JIS K0102 is not affected by bromine, but it is difficult to apply to an automatic measuring device, for example, it takes a long time such as 2 hours for measurement, and toxic waste liquid is generated.
【０００４】これらの欠点を解消するものとして、近
年、例えば臭素を吸着あるいは揮散させる方法や、塩化
物イオン濃度から臭素濃度を推定して補正する方法が提
案されているが、前者の方法は、手順が複雑で、自動計
測器には適用するのが困難であり、また、後者の方法
は、塩化物イオン濃度を測定するための塩化物イオン電
極が高価であるとともに、海水に対して感度が高過ぎ、
測定値の正確さや測定精度が十分ではないといった問題
点がある。In order to solve these drawbacks, in recent years, for example, a method of adsorbing or volatilizing bromine and a method of estimating and correcting bromine concentration from chloride ion concentration have been proposed. The procedure is complicated and difficult to apply to automatic measuring instruments, and the latter method is expensive in chloride ion electrodes for measuring chloride ion concentration and has high sensitivity to seawater. Too high,
There is a problem that the accuracy of the measurement value and the measurement accuracy are not sufficient.
【０００５】上述の問題は、海水試料の測定の場合のみ
ならず、工場排水のように非海水であって臭素を多く含
むような液体を試料とする場合にも同様に生じている。[0005] The above-mentioned problem occurs not only in the case of measuring a seawater sample, but also in the case of using a non-seawater liquid containing a large amount of bromine, such as factory drainage, as a sample.
【０００６】この発明は、上述の事柄に留意してなされ
たもので、高価な電極を用いたりすることなく、簡便
に、しかも短時間で、臭素の妨害影響を除去した液体中
の全窒素を定量する方法を提供することを目的としてい
る。SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned problems, and simply and in a short time without using expensive electrodes, removes the total nitrogen in the liquid from which the interference effect of bromine has been removed. It aims to provide a method for quantification.
【０００７】[0007]
【課題を解決するための手段】上記目的を達成するた
め、この発明では次のような手法を講じている。一つの
手法は、試料としての海水試料の吸光度を測定し、吸光
度と窒素濃度との関係を用いて前記海水試料のみかけの
全窒素濃度を求めるステップと、前記海水試料の導電率
を測定するステップと、導電率と海水濃度との関係から
前記海水試料の濃度を求めるステップと、標準海水中の
臭化物イオン濃度と前記海水試料の濃度とから海水試料
中に含まれる臭化物イオンの濃度を求めるステップと、
臭化物イオンと吸光度との関係を用いて臭化物イオンに
由来する吸光度を求めるステップと、吸光度と窒素濃度
との関係を用いて前記臭化物イオン妨害分に相当する窒
素濃度を求めるステップと、前記海水試料のみかけの全
窒素濃度から前記臭化物イオン妨害分に相当する窒素濃
度を引算するステップとから液体試料中の全窒素を定量
するようにしており、他の手法は、試料としての非海水
試料の吸光度を測定し、吸光度と窒素濃度との関係を用
いて前記非海水試料のみかけの全窒素濃度を求めるステ
ップと、 前記非海水試料の導電率を測定するステップ
と、導電率と臭化物イオン濃度との関係から前記非海水
試料に含まれる臭化物イオンの濃度を求めるステップ
と、臭化物イオンと吸光度との関係を用いて臭化物イオ
ンに由来する吸光度を求めるステップと、吸光度と窒素
濃度との関係を用いて前記臭化物イオン妨害分に相当す
る窒素濃度を求めるステップと、前記非海水試料におけ
るみかけの全窒素濃度から前記臭化物イオン妨害分に相
当する窒素濃度を引算するステップとから液体試料中の
全窒素を定量するようにしている。In order to achieve the above object, the present invention employs the following method. One method is to measure the absorbance of a seawater sample as a sample,
Determining the apparent total nitrogen concentration of the seawater sample using the relationship between the degree and the nitrogen concentration; measuring the conductivity of the seawater sample; and determining the concentration of the seawater sample from the relationship between the conductivity and the seawater concentration. Determining the concentration of bromide ions contained in the seawater sample from the bromide ion concentration in the standard seawater and the concentration of the seawater sample,
And determining the absorbance derived from bromide ions using the relationship between bromide ion and the absorbance, and determining the nitrogen concentration corresponding to the bromide ion interference amount by using the relationship between absorbance and concentration of nitrogen of the seawater sample Subtracting the nitrogen concentration corresponding to the bromide ion interference from the apparent total nitrogen concentration to determine the total nitrogen in the liquid sample, and other methods use non-sea water as the sample.
Measure the absorbance of the sample and use the relationship between the absorbance and the nitrogen concentration.
Determining a total nitrogen concentration of the non-seawater samples apparently have the steps of measuring the conductivity of the non-seawater samples, the non-seawater from the relationship between the conductivity and the bromide ion concentration
Determining the concentration of bromide ions in the sample
When the steps of obtaining and determining the absorbance derived from bromide ions using the relationship between bromide ion and the absorbance, the concentration of nitrogen corresponding to the bromide ion interference amount by using the relationship between absorbance and concentration of nitrogen, the non In seawater samples
So that quantify the total nitrogen concentration in the apparent total nitrogen in a liquid sample and a step of subtracting the nitrogen concentration corresponding to the bromide ion interference component that.
【０００８】[0008]
【作用】上記いずれの手法においても、試料の導電率を
測定することによって、その試料中に含まれる臭化物イ
オン濃度が求められる、そして、この臭化物イオンに由
来する吸光度を臭化物イオン妨害分に相当する窒素濃度
に換算し、試料の見かけの全窒素濃度から前記臭化物イ
オン妨害分に相当する窒素濃度を引算することにより、
臭素の妨害影響を除去した全窒素濃度を得ることができ
る。In any of the above methods, the concentration of the bromide ion contained in the sample is determined by measuring the conductivity of the sample, and the absorbance derived from the bromide ion corresponds to the bromide ion interference. By converting to nitrogen concentration, by subtracting the nitrogen concentration corresponding to the bromide ion interference from the apparent total nitrogen concentration of the sample,
It is possible to obtain a total nitrogen concentration from which the interfering effects of bromine have been eliminated.
【０００９】[0009]
【実施例】以下、具体的な数値とともにこの発明に係る
液体試料中の全窒素定量方法を説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for determining total nitrogen in a liquid sample according to the present invention will now be described with specific numerical values.
【００１０】まず、海水試料の全窒素定量方法につい
て、図１〜図４を参照しながら説明する。なお、（ ）
内の１…の番号は、全窒素測定フローの一例を示す図１
における番号と対応している。First, a method for determining total nitrogen in a seawater sample will be described with reference to FIGS. ()
1 in FIG. 1 show an example of the total nitrogen measurement flow.
Corresponding to the numbers in
【００１１】 まず、海水試料の導電率を測定する
（１）。この導電率測定に用いる装置としては、例え
ば、電極法の原理による液体導電率計ある。このとき得
られた導電率（２）が例えば４０ｍＳ／ｃｍであったと
する。ここで、図２に示すような導電率と海水濃度の相
関グラフ（３）を用いることにより、前記海水試料の濃
度（４）として７０％が得られる。First, the conductivity of a seawater sample is measured (1). As an apparatus used for the conductivity measurement, for example, there is a liquid conductivity meter based on the principle of the electrode method. It is assumed that the conductivity (2) obtained at this time is, for example, 40 mS / cm. Here, by using the correlation graph (3) between the conductivity and the seawater concentration as shown in FIG. 2, 70% is obtained as the concentration (4) of the seawater sample.
【００１２】 前記導電率測定とともに、海水試料の
全窒素を紫外線吸光光度法によって測定する（５）。そ
のときの吸光度が例えば０．２６であったとする。図３
は、吸光度と窒素濃度との相関グラフであり、このグラ
フを用いて、海水試料のみかけの全窒素濃度ａとして、
３．０ｍｇ／ｌが得られる（６）。ここで、みかけの全
窒素濃度ａとは、海水試料中の窒素成分と臭化物イオン
による妨害分とからなるものである。Along with the conductivity measurement, the total nitrogen of the seawater sample is measured by an ultraviolet absorption spectrophotometer (5). It is assumed that the absorbance at that time is, for example, 0.26. FIG.
Is a correlation graph of the absorbance and the nitrogen concentration, using this graph, as the apparent total nitrogen concentration a of the seawater sample,
3.0 mg / l are obtained (6). Here, the apparent total nitrogen concentration a consists of the nitrogen component in the seawater sample and the amount of interference by bromide ions.
【００１３】ところで、海水の組成は、外部からの影響
（雨、河川水の流入、海氷など）を受けるので、場所や
深さにより多少の差はあるが、その違いは通常ごくわず
かで、塩類相互間の含有比率はどこでもほぼ一定とみな
すことができる。下記表１（７）は、主要海水成分量を
表したものである〔『物性定数 １０集』（化学工学協
会編）による〕。By the way, since the composition of seawater is affected by external influences (rain, river water inflow, sea ice, etc.), there is some difference depending on the place and depth, but the difference is usually very small. The content ratio between the salts can be regarded as almost constant everywhere. Table 1 (7) below shows the amounts of main seawater components [according to “Physical Property Constants Vol.
【００１４】[0014]
【表１】 [Table 1]
【００１５】 そこで、前記のステップで求められ
た海水試料の濃度（７０％）（４）と、前記表１（７）
を用いて、臭化物イオン濃度を得る。具体的には、０．
０６７４×０．７を行って０．０４７２ｇ／ｋｇが得ら
れ、さらに、海水の密度が１．０３ｇ／ｃｍ3 であるか
ら、これを考慮して、０．０４７２ｇ／ｋｇ×１．０３
ｇを行い、４８．６ｍｇ／ｌが得られる（８）。Then, the concentration (70%) (4) of the seawater sample obtained in the above step and the above Table 1 (7)
Is used to obtain the bromide ion concentration. Specifically, 0.
By performing 0.674 × 0.7, 0.0472 g / kg was obtained and the density of seawater was 1.03 g / cm 3.
g to give 48.6 mg / l (8).
【００１６】 前記のステップで得られた濃度の臭
化物イオンに由来する吸光度がどの程度であるのかみる
のに、図４に示すような臭化物イオン濃度と吸光度の相
関グラフ（９）を用い、臭化物イオンに由来する吸光度
として、０．０４５が得られる（１０）。なお、この図
４は、種々の濃度の臭化物イオン水溶液（窒素成分を含
まない）を全窒素測定したときに臭化物イオン濃度と吸
光度との関係を表したもので、臭化物イオンが妨害を示
さなければ横軸に水平な直線のグラフになるはずであ
る。In order to determine the absorbance derived from the concentration of bromide ion obtained in the above step, a bromide ion concentration-absorbance correlation graph (9) shown in FIG. 0.045 is obtained as the absorbance derived from (10). FIG. 4 shows the relationship between the bromide ion concentration and the absorbance when bromide ion aqueous solutions (containing no nitrogen component) of various concentrations were measured for total nitrogen. It should be a horizontal straight line graph on the horizontal axis.
【００１７】 前記ステップで求められた吸光度
（０．０４５）と前記図３に示した吸光度と窒素濃度と
の相関グラフ（１１）とから臭化物イオンの妨害が窒素
濃度に換算していくらになるかを求める。この場合、臭
化物イオンの妨害を窒素濃度に換算した値ｂとして、
０．３ｍｇ／ｌが得られる（１２）。From the absorbance (0.045) obtained in the above step and the correlation graph (11) between the absorbance and the nitrogen concentration shown in FIG. 3, how much bromide ion interference is converted into nitrogen concentration Ask for. In this case, the interference of bromide ions is converted into a nitrogen concentration as a value b,
0.3 mg / l is obtained (12).
【００１８】 そして、前記ステップにおいて測定
したみかけの窒素濃度ａ（＝３．０ｍｇ／ｌ）から前記
ステップにおいて得られた臭化物イオンの妨害分ｂ
（＝０．３ｍｇ／ｌ）を引き算する（１３）ことによ
り、前記海水試料中における臭素分を除去した窒素の濃
度ｃを得ることができ、この場合、２．７ｍｇ／ｌが得
られる（１４）。Then, from the apparent nitrogen concentration a (= 3.0 mg / l) measured in the step, the amount of bromide ion interference b obtained in the step is calculated.
By subtracting (= 0.3 mg / l) (13), it is possible to obtain the nitrogen concentration c of the seawater sample from which bromine has been removed, and in this case, 2.7 mg / l is obtained (14). ).
【００１９】上述の各演算は、例えば、全窒素測定装置
のデータなどを処理するマイクロコンピュータなどによ
って行うことができ、前記各図や表などのデータはその
メモリに予めインプットしておけばよい。Each of the above-mentioned calculations can be performed by, for example, a microcomputer or the like which processes data of the total nitrogen measuring device, etc., and the data of each of the above-described figures and tables may be input to its memory in advance.
【００２０】下記表２は、窒素標準液（濃度２．００ｍ
ｇ／ｌ）に種々の濃度の臭化物イオンを添加した溶液を
試料として用い、０〜２ｍｇＮ／ｌ計を用いて測定した
ときの結果を示すものである。Table 2 below shows a nitrogen standard solution (concentration: 2.00 m
g / l) shows the results obtained by using a solution obtained by adding various concentrations of bromide ions to a sample and using a 0 to 2 mg N / l meter.
【００２１】[0021]
【表２】 [Table 2]
【００２２】上記表２から、７０ｍｇ／ｌの臭化物イオ
ンが試料中に共存する場合、上記補正を行わなければフ
ルケールに対して＋１８％もの大きな誤差が生ずるのに
対し、補正を行えば−５％にまで誤差が縮小されること
が判る。From the above Table 2, when 70 mg / l of bromide ions coexist in the sample, a large error of as much as + 18% with respect to full scale occurs without the above correction, whereas -5% with the correction. It can be seen that the error is reduced to.
【００２３】このように、この発明方法によれば、臭素
濃度がかなり高い海水が試料であっても、臭素の妨害影
響を除去した窒素濃度を、精度よくしかも簡単な装置を
用いるだけで得ることができる。As described above, according to the method of the present invention, even if the sample is seawater having a considerably high bromine concentration, it is possible to obtain the nitrogen concentration from which the interference effect of bromine has been eliminated by using a simple and accurate apparatus. Can be.
【００２４】上述の実施例は、試料が海水である場合の
全窒素定量方法であったが、この発明は、これに限られ
るものではなく、臭素を特別に多く含む工場排水（例え
ば一部の医薬、染料、繊維などの関係の工場からの排水
など）のように、非海水試料であっても同様に適用で
き、この場合は、予め、個別に非海水試料の導電率と臭
素濃度との関係を求めておけば、上記海水試料の場合と
同様の手順で、全窒素の定量を行うことができる。図５
は、非海水試料の全窒素測定フローの一例を示す。Although the above-described embodiment is a method for determining total nitrogen in the case where the sample is seawater, the present invention is not limited to this, and the present invention is not limited thereto. (E.g., effluent from factories related to pharmaceuticals, dyes, fibers, etc.), and can also be applied to non-seawater samples. In this case, the conductivity and bromine concentration of the non-seawater sample must be individually determined in advance. If the relationship is determined, the total nitrogen can be quantified in the same procedure as in the case of the seawater sample. FIG.
Shows an example of a total nitrogen measurement flow for a non-seawater sample.
【００２５】[0025]
【発明の効果】以上説明したように、この発明方法にお
いては、海水や非海水など試料の導電率を測定し、この
導電率に基づいて前記試料に含まれる臭素濃度を求め、
臭化物イオンの妨害による影響を巧みに補正するように
している。したがって、従来の自動測定装置で測定が困
難であった海水試料や臭素を特別に多く含む工場排水な
どの全窒素定量を、臭素の妨害影響を除去した状態で、
精度よくしかも簡単に測定することができる。したがっ
て、海域や河川、湖沼などの全窒素濃度の監視を容易に
行え、富栄養化などによる水質汚濁の進行防止に大きく
貢献できる。As described above, according to the method of the present invention, the conductivity of a sample such as seawater or non-seawater is measured, and the concentration of bromine contained in the sample is determined based on the conductivity.
The effect of bromide ion interference is carefully corrected. Therefore, the total nitrogen determination of seawater samples and factory wastewater containing extraordinarily large amount of bromine, which was difficult to measure with conventional automatic measurement equipment, was performed with the interfering effects of bromine removed.
It can be measured accurately and easily. Therefore, it is possible to easily monitor the total nitrogen concentration in the sea area, rivers, lakes, and the like, which can greatly contribute to preventing the progress of water pollution due to eutrophication and the like.
【図１】この発明の一実施例を示し、海水試料の全窒素
定量方法の一例を示すフロー図である。FIG. 1 is a flow chart showing one embodiment of the present invention and showing an example of a method for determining total nitrogen in a seawater sample.
【図２】海水濃度と導電率との関係を示す図である。FIG. 2 is a diagram showing a relationship between seawater concentration and electric conductivity.
【図３】窒素濃度と吸光度との関係を示す図である。FIG. 3 is a diagram showing the relationship between nitrogen concentration and absorbance.
【図４】全窒素測定における臭化物イオンの妨害の示す
図である。FIG. 4 is a diagram showing bromide ion interference in a total nitrogen measurement.
【図５】この発明の他の実施例を示し、非海水試料の全
窒素定量方法の一例を示すフロー図である。FIG. 5 is a flow chart showing another embodiment of the present invention and showing an example of a method for determining total nitrogen in a non-seawater sample.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ Ｇ０１Ｎ 33/18 Ｇ０１Ｎ 33/18 (72)発明者 福嶋 良助 京都府京都市南区吉祥院宮の東町２番地 株式会社堀場製作所内 (58)調査した分野(Int.Cl.7，ＤＢ名) G01N 21/00 G01N 21/27 G01N 21/31 G01N 21/77 G01N 27/06 G01N 33/18 ＪＩＣＳＴファイル（ＪＯＩＳ)──────────────────────────────────────────────────続 き Continuing on the front page (51) Int.Cl. 7 Identification code FI G01N 33/18 G01N 33/18 (72) Inventor Ryosuke Fukushima 2nd Higashi-cho, Kichijoin-gu, Minami-ku, Kyoto, Kyoto Inside Horiba, Ltd. (58) Fields surveyed (Int.Cl. 7 , DB name) G01N 21/00 G01N 21/27 G01N 21/31 G01N 21/77 G01N 27/06 G01N 33/18 JICST file (JOIS)
Claims (2)
し、吸光度と窒素濃度との関係を用いて前記海水試料の
みかけの全窒素濃度を求めるステップと、 前記海水試料の導電率を測定するステップと、 導電率と海水濃度との関係から前記海水試料の濃度を求
めるステップと、 標準海水中の臭化物イオン濃度と前記海水試料の濃度と
から海水試料中に含まれる臭化物イオンの濃度を求める
ステップと、 臭化物イオンと吸光度との関係を用いて臭化物イオンに
由来する吸光度を求めるステップと、 吸光度と窒素濃度との関係を用いて前記臭化物イオン妨
害分に相当する窒素濃度を求めるステップと、 前記海水試料のみかけの全窒素濃度から前記臭化物イオ
ン妨害分に相当する窒素濃度を引算するステップとから
なる液体試料中の全窒素定量方法。1. Measure the absorbance of a seawater sample as a sample
Determining the apparent total nitrogen concentration of the seawater sample using the relationship between the absorbance and the nitrogen concentration; measuring the conductivity of the seawater sample; and the relationship between the conductivity and the seawater concentration. Calculating the concentration of the seawater sample from the step; obtaining the concentration of the bromide ion contained in the seawater sample from the bromide ion concentration in the standard seawater and the concentration of the seawater sample; andusing the relationship between the bromide ion and the absorbance. Determining the absorbance derived from the bromide ion, and determining the nitrogen concentration corresponding to the bromide ion interference using the relationship between the absorbance and the nitrogen concentration; and the bromide ion from the apparent total nitrogen concentration of the seawater sample. Subtracting the nitrogen concentration corresponding to the amount of interference from the liquid sample.
し、吸光度と窒素濃度との関係を用いて前記非海水試料
のみかけの全窒素濃度を求めるステップと、 前記非海水試料の導電率を測定するステップと、導電率と臭化物イオン濃度との関係から前記非海水試料
に含まれる臭化物イオンの濃度を求めるステップと、 臭化物イオンと吸光度との関係を用いて臭化物イオンに
由来する吸光度を求めるステップと、 吸光度と窒素濃度との関係を用いて前記臭化物イオン妨
害分に相当する窒素濃度を求めるステップと、 前記非海水試料におけるみかけの全窒素濃度から前記臭
化物イオン妨害分に相当する窒素濃度を引算するステッ
プとからなる液体試料中の全窒素定量方法。2. The absorbance of a non-seawater sample as a sample is measured.
The non-seawater sample using the relationship between the absorbance and the nitrogen concentration.
Obtaining an apparent total nitrogen concentration; measuring the conductivity of the non-seawater sample; and measuring the conductivity of the non-seawater sample from the relationship between the conductivity and the bromide ion concentration.
Obtaining the concentration of bromide ions contained in the step, obtaining the absorbance derived from the bromide ions using the relationship between the bromide ions and the absorbance, and corresponding to the bromide ion interference using the relationship between the absorbance and the nitrogen concentration. Determining a nitrogen concentration to be performed, and subtracting the nitrogen concentration corresponding to the bromide ion interference from the apparent total nitrogen concentration in the non-seawater sample .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33860594A JP3342216B2 (en) | 1994-12-30 | 1994-12-30 | Method for determining total nitrogen in liquid samples |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33860594A JP3342216B2 (en) | 1994-12-30 | 1994-12-30 | Method for determining total nitrogen in liquid samples |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08184590A JPH08184590A (en) | 1996-07-16 |
| JP3342216B2 true JP3342216B2 (en) | 2002-11-05 |
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ID=18319752
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP33860594A Expired - Fee Related JP3342216B2 (en) | 1994-12-30 | 1994-12-30 | Method for determining total nitrogen in liquid samples |
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| Country | Link |
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| JP (1) | JP3342216B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW200741400A (en) * | 2006-02-23 | 2007-11-01 | Tokai Senko K K | Method for monitoring component concentration of dying solution |
| JP5199085B2 (en) * | 2006-06-30 | 2013-05-15 | 東海染工株式会社 | Staining liquid component concentration monitoring device, component concentration control device, and staining device |
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1994
- 1994-12-30 JP JP33860594A patent/JP3342216B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08184590A (en) | 1996-07-16 |
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