Справочник Пользователя для Hanna Instruments hi 93732

4

LED

EMITTED LIGHT

CUVET

MICROPROCESSOR

LIGHT

DETECTOR

The color of every object we see is determined by a process of

absorption and emission of the electromagnetic radiation (light) of its

molecules.
Colorimetric analysis is based on the principle that specific compounds

react with others and form a color, the intensity of which is

proportional to the concentration of the substance to be measured.
When a substance is exposed to a beam of light of intensity 

I

o

, a

portion of the radiation is absorbed by the substance's molecules and

a radiation of intensity 

I

, lower than 

I

o

, is emitted.

The quantity of radiation absorbed is given by the Lambert-Beer
Law:

log 

I

o

/

I

 = 

ε

λ

 

c d

Where

log 

I

o

/

I 

= Absorbance (A)

ε

λ

= molar extinction coefficient of the substance at

wavelength 

λ

c = molar concentration of the substance
d = optical distance light travels through sample

Therefore, the concentration "c" can be calculated from the color
intensity of the substance determined by the emitted radiation 

I

, as

the other factors are known.

BLOCK DIAGRAM OF A SPECTROPHOTOMETER

A monochromatic LED (Light Emitting Diode) emits radiation at a
single wavelength, supplying the system with the intensity 

I

o

.

Since a substance absorbs the color complimentary to the one it emits
(for example, a substance appears yellow because it absorbs blue
light), Hanna spectrophotometers use LEDs that emit the appropriate
wavelength to measure the sample.
The optical distance (d) is measured by the diameter of the cuvet
containing the sample.
The photoelectric cell collects the radiation 

I

 that is not absorbed by

the sample and converts it into an electric current, producing a
potential in the mV range.

13

HI 93732-01

Reagent kit for 100 D.O. tests

HI 93732-03

Reagent kit for 300 D.O. tests

HI 710009

Blue rubber boot

HI 710010

Orange rubber boot

HI 93700-C

Measurement cuvets (4 pcs)

HI 93703-50

Cleaning solution  for cuvets (230 mL)

HI 93703-70

Tissue for wiping cuvets (4 pcs)

MAN93732R1

Instruction manual

Hanna Instruments reserves the right to modify the design,
construction and appearance of its products without advance notice.

All Hanna Instruments meters are warranted for two years
against defects in workmanship and materials when used for their
intended purpose and maintained according to instructions.
This warranty is limited to repair or replacement free of charge.
Damages due to accidents, misuse, tampering or lack of prescribed
maintenance are not covered.
If service is required, contact the dealer from whom you purchased the
instrument. If under warranty, report the model number, date of
purchase, serial number and the nature of the failure. If the repair
is not covered by the warranty, you will be notified of the charges
incurred.
If the instrument is to be returned to Hanna Instruments, first obtain
a Returned Goods Authorization Number from the Customer Service
department and then send it with shipment costs prepaid. When
shipping any instrument, make sure it is properly packaged for
complete protection.
To validate your warranty, fill out and return the enclosed warranty
card within 14 days from the date of purchase.