Hanna Instruments c 214 Manual Do Utilizador
40
• Remove the cap from the vials and add the content of one packet
of HI 93767-0 Total Nitrogen Reagent to each vial. Replace the
cap tightly and shake gently the vials for 15 seconds.
cap tightly and shake gently the vials for 15 seconds.
• Wait for 2 minutes (without shaking the vials)
to allow the reaction to complete.
• Remove the cap from two Reagent Vials (
white cap vials).
• Add exactly 2.0 mL of digested sample (from the digested green
cap sample vial) to one Reagent Vial (sample vial), and 2.0 mL of
digested blank (from the digested green cap blank vial) to the
other Reagent Vial (blank vial), while keeping the vials at a 45-
degree angle.
digested blank (from the digested green cap blank vial) to the
other Reagent Vial (blank vial), while keeping the vials at a 45-
degree angle.
• Replace the cap tightly and invert
the vials 10 times.
Warning: as the vials become hot
during mixing, be careful in handling
them.
Note: the method is technique
sensitive: to obtain most reproducible
results it is strongly recommended
to follow carefully the “invert”
procedure described on page 14.
Warning: as the vials become hot
during mixing, be careful in handling
them.
Note: the method is technique
sensitive: to obtain most reproducible
results it is strongly recommended
to follow carefully the “invert”
procedure described on page 14.
←
white cap
→
Nitrogen, Total LR
41
• Place the blank vial into the holder
and push it completely down.
• Press TIMER and the display will show the countdown prior to the
measurement. Alternatively, wait for 5 minutes and press ZERO. In
both cases "SIP" will blink during measurement.
both cases "SIP" will blink during measurement.
• Wait for a few seconds and the
display will show “-0.0-”. Now the
meter is zeroed and ready for
measurement.
meter is zeroed and ready for
measurement.
• Remove the blank vial.
• Place the sample vial into the holder
and push it completely down.
• Press READ DIRECT and "SIP" will blink on the display.
• The instrument directly displays concentration in
mg/L of total
nitrogen (N) on the Liquid Crystal Display. The method detects all
organic and inorganic forms of nitrogen present in the sample.
organic and inorganic forms of nitrogen present in the sample.
• To convert the reading to mg/L of ammonia (NH
3
), multiply by a
factor of 1.22.
• To convert the reading to mg/L of nitrate NO
3
-
, multiply by a factor
of 4.43.
INTERFERENCES
Interference may be caused by:
Bromide (Br
Bromide (Br
-
):
above 60 mg/L (positive error)
Chloride (Cl
-
):
above 1000 mg/L (positive error)
Chromium (Cr
3+
): above 0.5 mg/L
Nitrogen, Total LR