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EVISA is providing a list of terms used in the area of speciation and fractionation analysis. Since speciation analysis is a field of analytical chemistry that is specified by a pronounced interdisciplinary cooperation between different sciences such as biochemistry, medicine, biology, environmental sciences, nutritional sciences and material sciences its terminology is a complex mixture of terms used in all these.

You may search for a term or browse the glossary alphabetically.

(In case that you cannot find the term you may consult more special glossaries or handbooks about nomenclature. For more details please consult EVISA's Link pages related to terminology,



UK Committee On Toxicity
"The Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) is an independent scientific committee that provides advice to the Food Standards Agency, the Department of Health and other Government Departments and Agencies on matters concerning the toxicity of chemicals."

The Committee on Toxicity of Chemicals (COT) is one of the independent committees that advise the UK Government's Food Standards Agency(FSA) and other UK Government departments. (Source: COT website )

a sequential process whereby a solution containing a solute of molecular size significantly greater than that of the solvent molecule is removed from the solvent by the application of a hydraulic poressure which forces only the solvent to flow through a suitable membrane, ususally having a pore size in the range of 0,001 - 0,1 micrometer

A variety of membrane filtration in which hydrostatic pressure forces a liquid against a semipermeable membrane.

ultrasonic nebulizer (USN)
A type of nebulizer that generates an extremely fine-droplet aerosol for introduction into the ICP mass spectrometer. The principle of aerosol generation using this approach is based on a sample being pumped onto a quartz plate of a piezoelectric transducer. Electrical energy of 1–2 MHz is coupled to the transducer, which causes it to vibrate at high frequency. These vibrations disperse the sample into a fine-droplet aerosol, which is carried in a stream of argon. With a conventional ultrasonic nebulizer, the aerosol is passed through a heating tube and a cooling chamber, where most of the sample solvent is removed as a condensate before it enters the plasma. However, commercial ultrasonic nebulizers are also available with membrane desolvation systems

Uncertainty is an estimate of error in mathematical terms. This expression must be defined exactly and is typically expressed using the standard deviation. Where error is the difference between the true value and a result or the mean, the uncertainty is an expression involving a calculation where the deviation (difference between mean and individual result) is used. The hope is that the true value (which will never be known by man) is within the expressed uncertainty under the specified conditions.

unimolecular dissociation
Unimolecular dissociation is the isolated, spontaneous dissociation of a neutral or an ion, based on the amount and distribution of its internal energy. In the electron ionization source, initial ionization of the molecule by the electrons leads to molecular ions, which then undergo rapid unimolecular dissociations leading to the fragment ions observed in the mass spectrum. Unimolecular dissociation that occurs  after the ions leave the source and in the field-free regions of  the mass spectrometer leads to metastable ions that can be  observed with special methods. Unimolecular dissociation is  contrasted with collision-induced dissociation, at least in  concept. True unimolecular dissociation evolves into collision-induced dissociation as the operating pressure of the  mass spectrometer increases.

unit resolution
The ability to distinguish between an ion at m/z and one at m/z + 1, with a defined valley height
between the peaks, across the effective mass range of an analyser. Typically the quoted resolving
power for a quadrupole analyser.

United Nations Environment Programme
"The United Nations Environment Programme (UNEP), established in 1972, works to encourage sustainable development through sound environmental practices everywhere. Its activities cover (...) the promotion of environmental science and information, to an early warning and emergency response capacity to deal with environmental disasters and emergencies."

See also UNEP.Net , which "delivers authoritative environmental information from a broad range of information and data providers (...)". (Source: UNEP website )

US Center for Disease Control and Prevention
"As the Center for Disease Control and Prevention (CDC) is recognized as the lead federal agency for protecting the health and safety of people - at home and abroad, providing credible information to enhance health decisions, and promoting health through strong partnerships. CDC serves as the national focus for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States."

"CDC, located in Atlanta, Georgia, USA, is an agency of the Department of Health and Human Services." (Source: CDC website )

US Environment Protection Agency
The Environment Protection Agency's of the USA was founded in 1970. It's "mission is to protect human health and to safeguard the natural environment — air, water, and land — upon which life depends."

The EPA enforces federal environmental protection laws. It registers and regulates pesticides, enforces laws covering outdoor air and drinking water quality and regulates the disposal of hazardous and solid wastes.

It has now grown into a big and powerful administration: "18,000 people in Headquarters program offices, 10 regional offices, and 17 labs across the country, EPA employs a highly educated, technically trained staff, more than half of whom are engineers, scientists, and environmental protection specialists. A large number of employees are legal, public affairs, financial, and computer specialists."

U.S. EPA's scientific publications are widely recognized as reference materials. (Source: US EPA website  )

US Food and Drug Administration
"The FDA is responsible for protecting the public health by assuring the safety, efficacy, and security of human and veterinary drugs, biological products, medical devices, our nation’s food supply, cosmetics, and products that emit radiation. The FDA is also responsible for advancing the public health by helping to speed innovations that make medicines and foods more effective, safer, and more affordable; and helping the public get the accurate, science-based information they need to use medicines and foods to improve their health." (Source: US FDA website )

US National Institute of Environmental Health Sciences

The US National Institute of Environmental Health Sciences (NIEHS) is one of 27 Institutes and Centers  of the National Institute of Health (NIH) , which is a component of the Department of Health and Human Services (DHHS) .

The National Institute of Environmental Health Sciences tries to reduce human illness from environmental causes by understanding environmental factors, individual susceptibility and age.

It conducts biomedical research programs, prevention and intervention efforts, and education.

It has collaborated to and published many highly recognized scientific publication. (Source: NIEHS website )

The United States Pharmacopeial Convention, Inc. (USP) establishes and disseminates officially recognized standards of quality and authoritative information for the use in the manufacture and testing of drugs, excipients, and raw materials. Also called one of the compendia. Other compendia include, for example, Ph.Eur (Pharmacopeia Europa), JP (Japanese Pharmacopeia).The USP, which defined specifications for approved drugs as well as general methods and guidance, merged with the NF, National Formulary, which focused on specifications for raw materials and excipients. General chapters are not legally binding, but specific chapters are considered to be binding, and defined USP methods are accepted by the FDA as an appropriate standard.

Ultraviolet-visible spectroscopy; an analytical technique that measures the absorption of light in the 200 to 750 nm range of the electromagnetic spectrum. UV-vis is often applied to HPLC detection.

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