-
Regarding a material quantity or instrument's reading; the dependence of a value on the direction of change from a previous characteristic
value. It may be quantified by the difference between the upscale and downscale variation
starting from fixed lower and upper measurement points (inversion).
Source:
PAC, 1990, 62, 2167
(Glossary of atmospheric chemistry terms (Recommendations 1990))
on page 2196
- (in solid-state transitions)
The difference in temperature or pressure for the transition of one phase to another
in the forward and reverse directions. It also refers to the corresponding difference
in magnetic, electric or stress field in reversing the sense of magnetic, electric
or strainpolarization in ferromagnetic, ferroelectric or ferroelastic materials.
Source:
PAC, 1994, 66, 577
(Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations
1994))
on page 583
- (in electroanalytical chemistry)
Hysteresis (electrode memory) occurs when there is a difference between the emf first
observed in a solution containing a concentration of A and a second observation of
the emf in the same solution after exposing the electrode to a different concentration
of A. The systematic error is generally in the direction of the concentration of the solution in which the electrode
was previously immersed. Hysteresis is thought to be a kinetic process. Normal, reversible
responses are expected when sufficient time is allowed for the system to return to
its initial condition.
See also: electrode memory
Source:
PAC, 1994, 66, 2527
(Recommendations for nomenclature of ionselective electrodes (IUPAC Recommendations
1994))
on page 2530