ISO 6650:2023

INTERNATIONAL ISO
STANDARD 6650
First edition
2023-10
Fertilizers, soil conditioners and
beneficial substances — Simultaneous
determination of N-(n-Butyl)
thiophosphoric triamide and
dicyandiamide by high-performance
liquid chromatography
Engrais, Amendements et Substances Bénéfiques — Détermination
Simultanée du N-buthylthiophosphore Triamide (NBPT) et du
Dicyandiamide (DCD) par Chromatographie Liquide à Haute
Performance (HPLC)
Reference number
ISO 6650:2023(E)
© ISO 2023

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ISO 6650:2023(E)
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© ISO 2023
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Published in Switzerland
ii
  © ISO 2023 – All rights reserved

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ISO 6650:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus and materials .2
7 Test procedure .3
7.1 General . 3
7.2 Preparation of test sample . 3
7.3 Preparation of the test solution . 3
7.4 HPLC conditions . 3
7.5 Determination of standard working solutions and sample test solutions . 4
7.5.1 Determination of standard working solutions . 4
7.5.2 Determination of sample test solutions . 4
8 Calculation and expression of results . 4
8.1 General . 4
8.2 Precision . .
...