Related Experiment Video
Updated: Jul 28, 2026

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles
Published on: April 19, 2018
Characterization of the NIST seaweed Standard Reference Material
I Outola1, J Filliben, K G W Inn
1National Institute of Standards and Technology, Gaithersburg, MD 20899, USA. iisa.outola@nist.gov
Abstract:
The National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) for seaweed was developed through an interlaboratory comparison with 24 participants from 16 countries. After evaluating different techniques to calculate certified values for the radionuclides, the median method was found to be the most representative technique. The certified values were provided for 13 radionuclides and information values were given for 15 more radionuclides. Results for the natural decay series showed disequilibrium in both the uranium and thorium series.
Related Concept Videos
Chemical Shift: Internal References and Solvent Effects
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
Red Algae

