1) Isotoop datering
De ouderdom van koolstof houdend materiaal tot 50.000 jaar oud vindt plaats op het Centrum voor Isotopen Onderzoek (CIO) met behulp van Acceleration Mass Spectrometrie (AMS). Voor de analyse kunnen monsters worden gebruikt van botten, hout en ander materiaal dat organische koolstof bevat. Onze wetenschappelijke staf helpt bij de analyse van resultaten.
The isotope 14C is produced in the atmosphere by cosmic rays, and enters organisms because of photosynthesis by plants, and because these plants directly or indirectly serve as food for animals and humans. 14C content in the organism is in principle constant during lifetime, but decays slowly after death (figure 1). The time after death of an organism can then be determined from its relative 14C content.
Radiocarbon - radiometric
The original method to determine14C concentration is based on couting radio-active decay. A high precision is possible with this method, but to get that result a large sample and a long measurement time are needed. The Center of Isotope Research has both the instrumentation for the original method and the newer method based on Accelerated Mass Spectrometry and is setting up a method based on Laser Spectrometry, giving great opportunity to compare all methods and to check calibrations. The original method is by now restricted to some samples where size does not matter.
Radio carbon AMS
The original method to determine age from the decay of 14C atoms is accurate but requires large samples and a long measurement time, because only a small fraction of the 14C atoms decay during a realistic measurement period. A smaller sample and measurement time can be obtained when also non-decaying 14C atoms are measured.
We develop methods based on14C measurements to independently quantify and verify the biogenic and fossil carbon fractions of fuels, flue gas CO2and atmospheric CO2. In the section background more details can be found about the background of this field of research.
The main objective is to gain knowledge about the sources and sinks of the main long-lived anthropogenic greenhouse gases CO2, CH4 and N2O.
|Laatst gewijzigd:||12 februari 2018 10:02|