
Contents
2.4.21
AOAC Official Method 983.01
Urea and Methyleneureas (Water-Soluble) in Fertilizers: Liquid Chromatographic Method
Get access
-
Published:January 2023
Cite
Urea and Methyleneureas (Water-Soluble) in Fertilizers: Liquid Chromatographic Method', in Dr. George W Latimer, Jr. (ed.), Official Methods of Analysis of AOAC INTERNATIONAL, 22nd Edition (
Extract
First Action 1983
Final Action 1984
(Method is not applicable to urea aldehyde condensate fertilizer products due to lack of separation of components present in the matrix from the urea peak.)
Principle
Test sample is ground to pass 40 mesh sieve, extracted with H2O, and filtered. Urea, methylenediurea (MDU), and dimethylenetriurea (DMTU) are determined by liquid chromatography using external standards and refractive index detection.
Apparatus
...
Reagents
...
Preparation of Test Solution
Grind sample to pass 40 mesh sieve. Accurately weigh 2.000 g well-mixed ground test sample into 200 mL volumetric flask. Add 150 mL distilled or deionized water, place on wrist-action shaker 20 min, and dilute to volume with H2O. Using glass fiber paper, filter portion into 4 mL vial. Filter again through 0.45 µm filter before injection.
Determination and Calculations
Inject 10 µL of each mixed standard until peak heights agree ±2%. Inject 10 µL test solution. Repeat standards after all test solutions have been injected. Standard peak heights should agree within 3% of initial standard peak heights. Average peak heights for each component and plot mg/mL vs peak heights.
Sign in
Personal account
- Sign in with email/username & password
- Get email alerts
- Save searches
- Purchase content
- Activate your purchase/trial code
- Add your ORCID iD
Purchase
Our books are available by subscription or purchase to libraries and institutions.
Purchasing informationMonth: | Total Views: |
---|---|
April 2024 | 9 |
May 2024 | 7 |
July 2024 | 4 |
August 2024 | 5 |
September 2024 | 4 |
November 2024 | 4 |
December 2024 | 11 |
January 2025 | 8 |
February 2025 | 4 |
March 2025 | 2 |
Get help with access
Institutional access
Access to content on Oxford Academic is often provided through institutional subscriptions and purchases. If you are a member of an institution with an active account, you may be able to access content in one of the following ways:
IP based access
Typically, access is provided across an institutional network to a range of IP addresses. This authentication occurs automatically, and it is not possible to sign out of an IP authenticated account.
Sign in through your institution
Choose this option to get remote access when outside your institution. Shibboleth/Open Athens technology is used to provide single sign-on between your institution’s website and Oxford Academic.
If your institution is not listed or you cannot sign in to your institution’s website, please contact your librarian or administrator.
Sign in with a library card
Enter your library card number to sign in. If you cannot sign in, please contact your librarian.
Society Members
Society member access to a journal is achieved in one of the following ways:
Sign in through society site
Many societies offer single sign-on between the society website and Oxford Academic. If you see ‘Sign in through society site’ in the sign in pane within a journal:
If you do not have a society account or have forgotten your username or password, please contact your society.
Sign in using a personal account
Some societies use Oxford Academic personal accounts to provide access to their members. See below.
Personal account
A personal account can be used to get email alerts, save searches, purchase content, and activate subscriptions.
Some societies use Oxford Academic personal accounts to provide access to their members.
Viewing your signed in accounts
Click the account icon in the top right to:
Signed in but can't access content
Oxford Academic is home to a wide variety of products. The institutional subscription may not cover the content that you are trying to access. If you believe you should have access to that content, please contact your librarian.
Institutional account management
For librarians and administrators, your personal account also provides access to institutional account management. Here you will find options to view and activate subscriptions, manage institutional settings and access options, access usage statistics, and more.