activation analysis


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ac·ti·va·tion a·nal·y·sis

the identification and quantification of unknown elements from their characteristic emissions and decay constants after they have been made radioactive by exposure to neutron or charged particle radiation.

neutron activation analysis

A method for identifying and measuring the concentrations of the chemical elements in a large and complex sample of material.

Method
A sample is rendered radioactive by bombarding it with neutrons, charged particles or gamma rays, making the nuclei of the different elements unstable and radioactive, and putting them in a higher energy state. Each of the now-radioactive isotopes in the sample gives off a characteristic signature (e.g., alpha particles, gamma rays), which indicates the type and concentration of the elements in the sample.

activation

the process of activating.

activation analysis
a method of analyzing the content of elements in samples of biological material. The sample is bombarded with nuclear particles and the elements in it measured by the radiation emitted by their radioactive daughter products. Called also radioactivation analysis.
activation energy
the difference in energy between the ground state of the reactants in a reaction and the point of maximum energy or transition state of the reactions. Usually lowered by enzyme catalysts.
activation factor
activation unit
the combination of complement (C4, C2 and C3) that binds to the antigen-antibody complex in the initial reaction step in the classical pathway of complement activation. See also complement.
References in periodicals archive ?
Arif, Radiochemical neutron activation analysis of trace impurities in high purity titanium and tungsten, Radiochim.
The particulate phases are filtered by inert polypropylene fiber filter and adsorption of solution phase thorium onto MnO2-coated fiber or preconcentration of thorium on XAD-2 resin by using adsorption of thorium-Xylenol Orange complexes which are subjected to alpha spectrometry or neutron activation analysis that relatively better methods for the quantification of low levels of thorium in water [122-125].
Bullet identification: A case of a fatal hunting accident resolved by comparison of lead shot using instrumental neutron activation analysis, Journal of Forensic Sciences (1992) 37(2):657-662.
5] were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), carbon fraction analysis, and neutron activation analysis (NAA).
All the samples were sent to Actlabs Laboratories of Ancaster, Ontario, for multi-element determination by ICP-MS and neutron activation analysis (INAA).
Environmental variation of arsenic levels in human blood determined by neutron activation analysis.
A second series of assays on the same samples by Neutron Activation Analysis is in progress in order to confirm the anomalies detected by ICP-MS.
BioPAL's core technology is stable isotope labeling of functional probes via neutron activation analysis - a technology that promises to significantly streamline the drug discovery process and improve clinical methods for measuring organ function.
BioPAL's core technology is stable isotope labeling of functional probes and neutron activation analysis -- a technology that promises to significantly streamline the drug discovery process and improve clinical methods for measuring organ function.
6, 1997-- Borealis Exploration Limited (CDN:BSXC, NASD:BOREF) announces initial Instrumental Neutron Activation Analysis (INAA) of a Roche Bay ~40% grade banded magnetite sample showing values of 6.
AntOro has received the Neutron Activation analysis results for the last 600 geochemistry soil samples taken during phase I of the exploration program.