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This relation is also represented as a normalized unit-less factor known as the retention factor, or retention parameter, which is the experimental measurement of the capacity ratio, as shown in the Figure of Performance Criteria as well. t R is the retention time of the specific component and t 0 is the time it takes for a non-retained ...
In chromatography, the retardation factor (R) is the fraction of an analyte in the mobile phase of a chromatographic system. [1] In planar chromatography in particular, the retardation factor R F is defined as the ratio of the distance traveled by the center of a spot to the distance traveled by the solvent front. [ 2 ]
In gas chromatography, the Kovats retention index (shorter Kovats index, retention index; plural retention indices) is used to convert retention times into system-independent constants. The index is named after the Hungarian-born Swiss chemist Ervin Kováts , who outlined the concept in the 1950s while performing research into the composition ...
The IUPAC Gold Book has no entry for retention factor in planar chromatography. Is the use of retention factor as in the article standard? --Kkmurray 02:30, 15 October 2008 (UTC) The Roberts/Gilbert/Martin undergrad lab text uses "retention factor" (and no other term) to describe Rf for TLC. DMacks 02:37, 15 October 2008 (UTC)
VOWD of EPC (contract) services are measured in terms of actual physical progress based on the documentary evidence of the deliverable produced. The VOWD is determined by applying the percentage of physical progress achieved to the current committed value of the cost of that item, which is in general the contract or purchase order value, including any approved changes.
The Services Index which is a weighted composite index for services data (similar to the Purchasing Managers' Index (PMI)) was developed and first published in the January 2008 Non-Manufacturing ISM Report On Business. This was not available prior to that date because there was insufficient services historical data to develop a composite index.
Retention distance, or R D, is a concept in thin layer chromatography, designed for quantitative measurement of equal-spreading of the spots on the chromatographic plate and one of the Chromatographic response functions. It is calculated from the following formula:
The Purnell equation is an equation used in analytical chemistry to calculate the resolution R s between two peaks in a chromatogram. [1] [2]= (′ + ′) where R s is the resolution between the two peaks