Hanna Instruments HI 4101, Инструкция по эксплуатации, Страница: 6 / 20

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V. V.V.
V. V. Equipment Required:
Equipment Required:
Equipment Required: Equipment Required: Equipment Required:
•
Hanna HI 4222 pH/ISE/mV meter or other suitable
ion or pH/mV meter. (Note: log/linear graph paper is
useful if an ISE meter is not available).
•
Hanna HI 180 magnetic stirrer or equivalent with
stirring bars. (Note: Isolate beakers from stirrer motor
heat by placing insulating material such as foam or
cork between them).
•
Hanna HI 4000-71 gas sensor test vessel or
•
Hanna HI 76404 electrode holder or equivalent with
Beakers or other suitable measurement vessel with
plastic sealing film or wrap.
VI. VI.
VI. VI. VI. Solutions Required for Calibration:
Solutions Required for Calibration:
Solutions Required for Calibration: Solutions Required for Calibration: Solutions Required for Calibration:
Ionic Strength Adjuster (ISA): HI 4001-00
Hanna 0.1 M standard: HI 4001-01
Hanna 100 ppm N standard: HI 4001-02*
Hanna 1000 ppm N standard: HI 4001-03*
*Please Note: These calibration standards are ppm as
NH
3
-N.
See Section XVII for additional solutions used for mainte-
nance.
Using volumetric pipettes and glassware make dilutions of
the standard to bracket the concentration of the samples.
Standards with concentrations less than 10
-3
M should be
prepared fresh daily. Store solution in a tightly sealed
bottle without ISA added. 2 mL of HI 4001-00 ISA should
be added to each 100 mL sample of standard and samples
just prior to measurement. ISA adjusts the pH of the sample
or standard to about pH 11 thus converting ammonium ion
to ammonia. It also provides samples and standards a
constant ionic strength background that stabilizes the solu-
tions activity coefficient and permits concentration to be
measured directly. The ISA provides color indication to verify
it has been added to the solution and a complexing agent
to remove metal ions (i.e copper, zinc) from solution. These