Page 4 - Shimadzu MXF-2400
P. 4
Principle Construction
When X-rays hit a sample, atoms in the sample are excited and release the secondary X-rays, which are also called fluorescent X-rays.
Since the wavelength of secondary X-rays is peculiar to the element concerned, the sample can be qualitatively determined by measuring
that wavelength. Also, since the fluorescent X-ray intensity is proportional to the concentration of the element, quantitative
determination is made by measuring the fluorescent X-ray intensity of the wavelength peculiar to each element.
1
Focusing circle
Detector X-ray tube
Detector
Secondary slit 2
Secondary slit 3
2θ 2
2θ 2 6
Curved crystal
Curved crystal 4 7
Primary slit
Primary slit
Sample
Concentration
Concentration (%) calculation X-ray intensity (kcps) 8
Si 3.1182 Si 34.79725
Mn 0.2011 Intensity Mn 6.30588
P 0.0209 P 0.45881 5
S 0.0173 S 1.11912
Mg 0.0185 Concentration Mg 0.11576
9
Spectrometer Unit Measuring Electronics
This unit disperses the fluorescent X-rays generated from the The electric pulses corresponding to the number of X-ray photons
sample, measures the intensity of the X-rays of the particular are counted and recorded. — The output pulse signal of the
1 X-ray Spectrometer (Installed in the case) 6 Data Processing Unit
wavelength, and converts that intensity into electric signals. High detector is amplified and its interfering spectrum signals are
quality curved crystals are used for dispersion. removed by the pulse height analyzer. Then the signal is measured Up to 36 monochromators are radially arranged around The operation of the MXF-2400 is made via the keyboard
the X-ray tube. The case of the X-ray spectrometer is of this unit. This unit has various high-level data handling
The MXF-2400 uses one monochromator for one element, and up by the scaler, processed by the microprocessor, and then
temperature-controlled. functions, which provides advanced analysis by easy
to 36 monochromators can be installed together to permit transmitted to the data processing unit.
operation.
simultaneous determination of up to 36 elements.
2 Sample Turntable (with dust-proof cover)
Use of the optional scanning monochromator provides automatic 7 X-ray Power Control Unit and
qualitative analysis and allows up to 30 elements to be preset for Up to eight samples may be loaded together for Processor Unit
quantitative analysis. automated successive analysis. An external automatic
sample feeder and/or automatic sample pretreatment unit The X-ray power control unit controls the output power
may be connected to this turntable. of the X-ray tube with such a high stability that it is not
X-ray Power Source Data Processing Unit necessary to use a motor generator in most cases. The
3 Sample Feeding Unit processor unit incorporates the X-ray intensity measuring
This unit supplies power to the X-ray tube which emits the X-ray intensities are converted into concentration values of the
(Installed behind the panel) circuit and the microprocessor, which counts X-ray pulses
excitation X-rays (primary X-rays). It consists of a high-voltage elements concerned through the use of the conversion equations and controls all the other units.
transformer and an X-ray power controller. (calibration curves) predetermined using standard samples. The The swing arm system accurately positions the sample.
results are presented on the display or the printer. 8 DC Power Source Unit
4 Maintenance Panel
This unit supplies DC power to the control units.
Spectrometer This unit displays the status of each part and has manual
unit
switches for checking.
Measuring electronics Data processing unit
Mono- 9 Switchboard
Microprocessor Keyboard 5 X-ray Tube Cooling Unit The necessary power source is one three phase 200 VAC
chro- Display
X-ray power source meter Detector
Printer
PHA scaler This unit circulates cool, distilled water to the X-ray tube. or 220 VAC line.
X-ray tube Amplifier
The distilled water is cooled externally.
MXF-2400
Multi-Channel X-ray Fluorescence Spectrometer