Glossary for the Non-Scientist

Compiled by Zara Fewsmith

June 2007

 

AFM- Atomic force microscope. This is a very high- resolution microscope that is mostly used for imaging, measuring, and manipulating matter at the nanoscale 1 x 10-9 (one billionth of a meter) or atomic scale 1 x 10-10 m (one ten billionth of a meter)

 

Annealing- a heat treatment where a material is altered, causing changes in its properties, such as strength and hardness. In this process, the substance is first heated and maintained at a certain temperature and then cooled very slowly. At a high temperature this may result in the oxidation of a metal’s surface.

 

Corrosion- the deterioration of essential properties in a substance due to reactions with its surroundings. Usually this word refers to metals reacting with water or oxygen.

 

EDAX- Energy-Dispersive X-ray analysis. An electron beam strikes the surface of a conducting sample. This causes X-rays to be emitted from the sample. The energy of the X-rays emitted depends on the material under examination. By moving the electron beam across the material an image of each element in the sample can be acquired.   

 

Eutectic- A eutectic mixture is a mixture of two or more solid phases at a composition that has the lowest melting point.

 

Isotopes- different forms of an element that have a different atomic mass and a different number of neutrons but have the same atomic number (the same number of protons). Isotopes will exhibit nearly identical chemical behavior.

 

Oxidation- An oxidation reaction describes all chemical reactions in which atoms have their oxidation number changed.

 

SEM- Scanning electron microscopy. A scanning electron microscope is capable of producing high-resolution images of a sample surface. SEM images have a characteristic three-dimensional appearance and are useful for judging the surface structure of the sample.

 

SIMS- Secondary ion mass spectrometry. A focused ion beam is directed at a solid surface, removing material in the form of neutral and ionized atoms and molecules. The ionized molecules are then accelerated into a mass spectrometer and are mass analyzed.

 

Spallation- the process in which a heavy nucleus emits a large number of nucleons as a result of being hit by a high-energy proton. This causes its atomic weight to decrease greatly.

 

Steel- a mixture of two or more elements that consists mostly of iron and that has metallic properties; however, it usually has different properties from those of its components.

Austenite- a type of steel that is a metallic non-magnetic solid solution of iron, carbon, nickel, and chromium. It has a face-centered cubic structure allows it to hold a higher proportion of carbon.

Ferrite- This is another term for iron, or a solid solution with iron as the main      constituent. It has a body-centered cubic crystal structure and is the component      that gives steel and cast iron their magnetic properties.

Martensite- any crystal structure formed by a reaction in which an element         appears to move out of one compound and into another (a single-replacement reaction).   

 

Transmutation- Nuclear transmutation converts radioactive isotopes into different isotopes by changing their nuclear structure. This is accomplished by neutron-capture processes or by neutron-induced fission. The most dangerous materials in spent nuclear fuel are transformed into stable and safe waste. The life span of this waste can be greatly reduced.

 

WDX- Wavelength dispersive X-ray spectroscopy. This is a method, mostly used in chemical analysis, which determines the energy spectrum of an X-ray radiation. In this process electrons are directed at the sample causing it to emit X-rays which are then analyzed by wavelength.

 

XPS- X-ray photoelectron spectroscopy. This is a technique that measures the elemental composition of the sample. In this process X-rays are directed at the sample causing it to emit electrons which are then energy-analyzed.