What is the analysis of neutron activation?
The neutron activation analysis (NAA) is a very sensitive and accurate method of determining the elements present in the material sample. The sample is targeted with neutrons from a radioactive source. This causes many elements to be emitted by gamma rays at specific frequencies that can be identified. In this way, approximately 65 different elements can be detected. It is one of the most useful scientific techniques for exploring the elemental composition of samples and has many applications in analytical chemistry, geology, forensic science and other areas. In many cases, these isotopes are unstable and, after a short delay, break into another, lighter isotope and emit one or more gamma beams in energies that are characteristic of this isotope. For example, the most common sodium isotope-sodium-23-can absorb neutron, forming unstable sodík-24 isotope, which then disintegrates into magnesium-24 and emits two gamma rays in specific energies. By measuring gamma beams and emitted quantity, present can be determinedNo elements and their abundance in the sample. The initial gamma beam, issued immediately when neutron is absorbed, is known as a fast gamma beam, but usually delayed gamma rays are measured.
Analysis of neutron activation is a very sensitive technique. It can detect elements in one part per million or less and in some cases up to one part per billion. The method is also very versatile because it can analyze samples in solid, liquid and gas forms and can handle samples size to 0.000035 ounces (0.001 grams).
The source of neutrons is sometimes known as a neutron howly. When some light elements are subjected to alpha particles neutrons. Berylium is particularly suitable for this purpose. By mixing the berylia with the source of alpha particles, such as Plutonium 239 or Radium 226, a strong neutron source can be created. It can be closed in suitable radiation but with an opening where they may appear to disappearRony.
nuclear reactors are also used as neutron sources. In the US in the Oak Ridge in Tennessee, the NEPRONAL NEPRONAL LABORATORY Oak Netrons source provides an isotope reactor, making it a main neutron activation center. Radioactive elements that produce neutrons by nuclear cleavage, such as Californium-252, can also be used on a smaller scale, allowing the neutrons sources of the size of the area.
Neutron activation analysis has a wide range of applications. It can be used in the production industry to detect dirt in metals, in biology to explore the metabolism of trace elements, in geology to analyze the samples of rock and soil, and in forensic science to obtain key information from the samples of the crime scene. One of the known specific examples of neutron activation analysis is to find that all fragments of missiles from the scene of the assassination of John F. Kennedy came from the same two bullets fired from the same weapon. Another example was the discovery of the layer withDiment rich in Iridium on the border between chalk and tertiary geological periods, indicating the main impact of meteorite, which more or less coincided with the event of a mass extinction, which indicated the demise of dinosaurs.