Electrothermal vaporization ( ETV ) and in torch vaporization ( ITV ) use hot surfaces ( graphite or metal, generally ) to vaporize samples for introduction.

Graphite furnace atomic absorption spectrometry ( GFAAS ) ( also known as Electrothermal Atomic Absorption Spectrometry ( ETAAS )) is a type of spectrometry that uses a graphite-coated furnace to vaporize the sample.

The so-called Stabilized Temperature Platform Furnace ( STPF ) concept, proposed by Walter Slavin, based on research of Boris L ’ vov, makes ET AAS essentially free from interference.

In ET AAS a transient signal is generated, the area of which is directly proportional to the mass of analyte ( not its concentration ) introduced into the graphite tube.

It shows a very high degree of freedom from interferences, so that ET AAS might be considered the most robust technique available nowadays for the determination of trace elements in complex matrices.

Another source of background absorption, particularly in ET AAS, is scattering of the primary radiation at particles that are generated in the atomization stage, when the matrix could not be removed sufficiently in the pyrolysis stage.

As measurement of total and background absorption, and correction for the latter, are strictly simultaneous ( in contrast to LS AAS ), even the fastest changes of background absorption, as they may be observed in ET AAS, do not cause any problem.

In LS AAS background absorption can only be corrected using instrumental techniques, and all of them are based on two sequential measurements, firstly, total absorption ( atomic plus background ), secondly, background absorption only, and the difference of the two measurements gives the net atomic absorption.

In HR-CS AAS background correction is carried out mathematically in the software using information from detector pixels that are not used for measuring atomic absorption ; hence, in contrast to LS AAS, no additional components are required for background correction.

It has already been mentioned that in HR-CS AAS lamp flicker noise is eliminated using correction pixels.

* H. Becker-Ross, S. Florek, U. Heitmann, R. Weisse ( 1996 ), Influence of the spectral bandwidth of the spectrometer on the sensitivity using continuum source AAS, Fresenius J. Anal.

There is an increasing trend of using ICP-MS as a tool in speciation analysis, which normally involves a front end chromatograph separation and an elemental selective detector, such as AAS and ICP-MS. For example, ICP-MS may be combined with size exclusion chromatography and quantitative preparative native continuous polyacrylamide gel electrophoresis ( QPNC-PAGE ) for identifying and quantifying native metal cofactor containing proteins in biofluids.

The acid droplets, condensed on the surface, are then analyzed using AAS.

The oldest and most commonly used atomizers in AAS are flames, principally the air-acetylene flame with a temperature of about 2300 ° C and the nitrous oxide ( N2O )- acetylene flame with a temperature of about 2700 ° C.

This might sound complex, but first of all the number of di-atomic molecules that can exist at the temperatures of the atomizers used in AAS is relatively small, and second, the correction is performed by the computer within a few seconds.

The modern form of AAS was largely developed during the 1950s by a team of Australian chemists.

The research with high-resolution ( HR ) CS AAS was pioneered by the groups of O ’ Haver and Harnly in the USA, who also developed the ( up until now ) only simultaneous multi-element spectrometer for this technique.

The first commercial equipment for HR-CS AAS was introduced by Analytik Jena ( Jena, Germany ) at the beginning of the 21st century, based on the design proposed by Becker-Ross and Florek.

The Pontifical Academy of Social Sciences was established by Pope John Paul II on 1 January 1994 ( AAS 86, 213 ), with the aim of promoting the study and progress of the social sciences, primarily economics, sociology, law and political science.

It was named Wheeler Field on 11 November 1922 in honor of Major Sheldon H. Wheeler, former commander of Luke Field on Ford Island, killed in the crash of DH-4B, AAS Ser.

The first major competition was the tremendously popular 1908 All-Alaska Sweepstakes ( AAS ), which was started by Allan " Scotty " Alexander Allan, and ran from Nome to Candle and back.

The AAS name of the society was not finally decided until 1915, previously it was the " Astronomical and Astrophysical Society of America ".

In addition to her fair work, between 1835 and 1865, Chapman served on the executive and business committees of the Massachusetts Anti-Slavery Society ( MASS ), the New England Anti-Slavery Society ( NEASS ) and the American Anti-Slavery Society ( AAS ) and was active in the petition campaigns of the 1830s.

She also acted as editor to The Liberator in Garrison ’ s absence and was on the editorial committee of the National Anti-Slavery Standard, the official mouthpiece of the AAS.

Throughout his career he played an active role in the development of public policy for the medical sciences in Australia and was a founding member of the Australian Academy of Science ( AAS ), and served as its president from 1965 to 1969.

The Trust Board was created by the Auckland Astronomical Society ( AAS ) in 1956.

From 1973-2004 it was awarded by the American Association of University Women on advice from the AAS.

In the 1980s, South Hall opened in the Bronx and Monroe celebrated its fiftieth anniversary and was authorized to grant a second associated degree ( AAS )

Later in its history, AAS was cimbined with other French aeronautical firms into the government-sponsored SNCASO aerospace conglomerate.

This initiative was further developed and presented to the Advances in the Astronautical Sciences ( AAS ) Meeting dedicated to Aerospace Century XXI in Boulder, Colorado in 1986.

The race was modeled after the 1908 to 1918 All-Alaska Sweepstakes ( AAS ) of Nome, and was named the Iditarod Trail Seppala Memorial Race, after the three-time champion Leonhard Seppala.

The race was modeled after the first large dog sled race in the state, the 1908 to 1918 All-Alaska Sweepstakes ( AAS ) of Nome.

While Seppala was most famous for participating in the 1925 serum run which saved the city of Nome from a diphtheria epidemic, according to Page " Seppala was picked to represent all mushers ... but it could just as easily have been named after Scotty Allan " ( the founder of the AAS ).

When the Federal Aviation Administration ( FAA ) awarded the contract of the Advanced Automation System ( AAS ) to IBM Federal Systems, the work was performed at a newly constructed campus in Rockville, Maryland.

Atomic absorption spectroscopy ( AAS ) is a spectroanalytical procedure for the quantitative determination of chemical elements employing the absorption of optical radiation ( light ) by free atoms in the gaseous state.

In classical LS AAS, as it has been proposed by Alan Walsh, the high spectral resolution required for AAS measurements is provided by the radiation source itself that emits the spectrum of the analyte in the form of lines that are narrower than the absorption lines.

In LS AAS the high resolution that is required for the measurement of atomic absorption is provided by the narrow line emission of the radiation source, and the monochromator simply has to resolve the analytical line from other radiation emitted by the lamp.

Another feature to make LS AAS element-specific is modulation of the primary radiation and the use of a selective amplifier that is tuned to the same modulation frequency, as already postulated by Alan Walsh.

This way any ( unmodulated ) radiation emitted for example by the atomizer can be excluded, which is imperative for LS AAS.

Congruence of triangles is determined by specifying two sides and the angle between them ( SAS ), two angles and the side between them ( ASA ) or two angles and a corresponding adjacent side ( AAS ).

The shape of a triangle is determined up to congruence by specifying two sides and the angle between them ( SAS ), two angles and the side between them ( ASA ) or two angles and a corresponding adjacent side ( AAS ).

In 1996 the same George Gatewood prominently announced at an AAS meeting and to the popular press the discovery of multiple planets in this system, detected by astrometry.

Similar prizes are awarded by AAS divisions.