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食品から硝酸塩を過剰に摂取すると、特に小さな子供や感受性の高い大人にチアノーゼが起こることが以前から知られています。WHO の規格では、人が c(NO3-) ≥ 50 mg/L の硝酸塩を摂取すると危険とされています。しかし、最近の研究では、人体内の硝酸塩濃度が高すぎると、（亜硝酸塩を介して）発がん性が指摘され、さらに危険なニトロソアミンが生成される可能性があることが明らかになりました。硝酸アニオンを測定するための既知の測光メソッドは、時間がかかり、広範囲にわたる干渉を受けやすくなります。硝酸塩分析の重要性がますます高まる中、選択的かつ迅速で、比較的正確な分析法の要求も高まっています。この技術資料では、水サンプル、土壌抽出物、肥料、野菜、飲料の硝酸塩濃度を迅速測定した応用例を紹介しています。

「マンガンを測定するための高感度のメソッドについて説明しています。これは、そこに含まれているマンガン濃度が重要とされる地下水、飲料水、および地表水の調査に主に適しています。メソッドは、もちろん他のマトリックスでの微量分析にも用いることができます。マンガンはアノードストリッピングボルタンメトリー (ASV) によってアルカリ性ホウ酸緩衝液で測定されます。亜鉛イオンをサンプルに添加することにより、金属間化合物による干渉を防ぐことができます。測定限界は b(Mn) = 2 µg/L です。」

This bulletin describes the determination of calcium, magnesium, and alkalinity in water by complexometric titration with EDTA as titrant. It is grouped into two parts, the potentiometric determination and the photometric determination.There are multiple definitions of the different types of water hardness. In this Application Bulletin, the following definitions are used: alkalinity, calcium hardness, magnesium hardness, total hardness, and permanent hardness. Explanations of these definitions and other expressions are provided in the Appendix.Determination of alkalinity during the photometric part is carried out in a separate acid-base titration before the complexometric titration of calcium and magnesium in water. Permanent hardness can be calculated from these values. The determination of calcium and magnesium in beverages (fruit and vegetable juices, wine) is also described.The photometric part includes the determinations of total and calcium hardness and thereby indirectly magnesium hardness using Eriochrome Black T and calconcarboxylic acid as indicators (in accordance with DIN 38406-3).

This Bulletin describes a simple polarographic method for the determination of quinine in drinks and tablets. Whereas in drinks quinine can be determined directly, in the case of tablets it must first be extracted. The limit of quantification is 0.2 mg/L or 4 μg/tablet.

Nitrite can be determined polarographically after its conversion to diphenylnitrosamine (C6H5)2NNO. Potassium thiocyanate is used as a catalyst in order for the conversion to proceed rapidly and quantitatively. The reaction takes place in acid solution at a pH value of approx. 1.5. The limit of quantification is 5 μg/L NO2-.

In our Instructions for Use for the 656 Electrochemical Detector the user will find all the basic information about how it works and how to use it as well as how to handle the electrodes. They also contain information about the demands placed on the separating system together with the causes of and remedies for detection problems.Application Bulletin no. 128 is intended to provide an overview of the most important substance classes and mention some compounds that can easily be determined oxidatively, i.e., with detection limits in the pg range; it also mentions possible working conditions for separation and electrochemical detection and illustrates them with examples.

After acid digestion, the sample solution is neutralized with sodium hydroxide to form sodium dihydrogen phosphate. An excess of lanthanum nitrate is added and the released nitric acid is then titrated with sodium hydroxide solution.NaH2PO4 + La(NO3)3 → LaPO4 + 2 HNO3 + NaNO3This determination method is suitable for higher phosphate concentrations.

Besides acid-base titrations, the titrimetric determination of chloride is one of the most frequently used titrimetric methods of analysis. It is employed more or less frequently in practically every laboratory. This Bulletin shows you how to determine chloride in a wide range of concentrations using automatic titrators. Silver nitrate is normally used as titrant (for environmental reasons one should refrain from using mercury nitrate). The titrant concentration depends on the chloride content of the sample to be analyzed. It is crucial to choose the correct electrode for samples with low chloride contents.

このApplication Bulletinでは、水サンプル、透析液、塩化ナトリウム溶液、消化液 (例えば凍結乾燥物などの) に含まれるアルミニウムの測定のための電圧電流法について説明しています。このメソッドは、カルコン (エリオクロムブルーブラックR) によるAl3+イオンの錯体生成を用いています。形成された錯体は、60°Cで簡単に電気化学的還元が可能です。定量下限は、用いる試薬の純度によって異なりますが、およそ5 µg/Lです。

A method is described in this Bulletin that allows molybdenum to be determined in steel and other materials containing a high iron concentration. Mo(VI) is determined at the dropping mercury electrode by catalytic polarography. The determination limit is approx. 10 μg/L Mo(VI).