Catálogo Hanna Instruments V31

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Glossary
BOD
Biochemical Oxygen Demand (BOD) gives
an indication of the biodegradable organic
material present in a sample of water. The
dissolved oxygen concentration is measured
before and after an incubation period of
5 days and the BOD is calculated in mg/L
from the difference.
%Brix
Degrees Brix is a unit representative of the
sugar content of an aqueous solution. One
degree Brix corresponds to 1 gram of sucrose
in 100 grams of solution (%w/w).
°C
Celsius temperature degree; °C = (°F-32) / 5/9
CAL Check™
With the Hanna exclusive CAL Check
validation function, users are able to verify
the performance of the instrument at any
time. Taking just a few short steps, the
validation procedure is extremely user
friendly and ensures that the meter is
properly calibrated.
Calibration
Calibration is the validation of specific
measurement techniques and equipment.
The bias is the difference between the mean
of the measurements and the reference
value. The procedure that establishes and
corrects the bias is the calibration.
At the simplest level, calibration is a
comparison betweenmeasurements — one of
known magnitude or correctness made or set
with one device and another measurement
made in as similar a way as possible with a
second device.
Calibration is often regarded as including the
process of adjusting the output or indication
on a measurement instrument to agree with
the value of the applied standard, within a
specified accuracy.
CAL Check™ System
When used in tandem with a CAL Check™
meter, CAL Check™ equipped electrodes
permit users to be informed if they have
performed a proper calibration. In the event
of a dirty or broken electrode or contaminated
buffer solution, the system alerts the user
to either check the electrode, replace the
buffer solution or both. The system also
reminds users when the instrument should
be recalibrated.
Calibration Curve
In analytical chemistry, a calibration curve
is a general method for determining the
concentration of a substance in an unknown
sample by comparing the unknown to a set of
standard samples of known concentration.
A calibration curve is one approach to the
problem of instrument calibration; other
approaches may mix the standard into the
unknown, giving an internal standard.
The calibration curve is a plot of how the
instrumentalresponse,thesocalledanalytical
signal, changes with the concentration of
the analyte (the substance to be measured).
The operator prepares a series of standards
across a range of concentrations near
the expected concentration of analyte in
the unknown. The concentrations of the
standards must lie within the working range
of the technique (instrumentation) they are
using. Analyzing each of these standards
using the chosen technique will produce a
series of measurements. For most analyses,
a plot of instrument response vs. Analyte
concentration will show a linear relationship.
The operator can measure the response of
the unknown, and using the calibration curve,
they can interpolate to find the concentration
of analyte.
Candela
The candela is the luminous intensity, in
a given direction, of a source that emits
monochromatic radiation of frequency 540
× 1012 hertz and that has a radiant intensity
in that direction of 1/683 watt per steradian.
CaT
Calcium tartrate
CE Mark
See page 17.4
Checker®
Hanna pocket-sized electronic meter.
17
Glossary
17.7 |