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A certified reference material is a particular form of measurement standard. Reference materials are particularly important for analytical chemistry and clinical analysis. [2] Since most analytical instrumentation is comparative, it requires a sample of known composition (reference material) for accurate calibration.
The δ values and absolute isotope ratios of common reference materials are summarized in Table 1 and described in more detail below. Alternative values for the absolute isotopic ratios of reference materials, differing only modestly from those in Table 1, are presented in Table 2.5 of Sharp (2007) [1] (a text freely available online), as well as Table 1 of the 1993 IAEA report on isotopic ...
A primary standard in metrology is a standard that is sufficiently accurate such that it is not calibrated by or subordinate to other standards. Primary standards are defined via other quantities like length, mass and time. Primary standards are used to calibrate other standards referred to as working standards. [1] [2] See Hierarchy of Standards.
Pharmacopoeial reference standards are a subset of pharmaceutical reference standards. They are established for the intended use described in pharmacopeial texts (monographs and general chapters). Pharmacopeial reference standards are available from various pharmacopoeias such as United States Pharmacopeia and the European Pharmacopoeia. Where ...
Elemental analysis is a process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition.
Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...
In chemistry, a reagent (/ r i ˈ eɪ dʒ ən t / ree-AY-jənt) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. [1] The terms reactant and reagent are often used interchangeably, but reactant specifies a substance consumed in the course of a chemical reaction. [ 1 ]
Characterization, when used in materials science, refers to the broad and general process by which a material's structure and properties are probed and measured. It is a fundamental process in the field of materials science, without which no scientific understanding of engineering materials could be ascertained.