Instrument for detecting calcium, silicon, and magnesium in stones and stone powder.

Instrument for detecting calcium, silicon, and magnesium in stones and stone powderInstrument for detecting calcium, silicon, and magnesium in stones and stone powder

W---- Weight percentage content of the element in raw material

A---- Amplification factor

Elements such as calcium, iron, aluminum, and silicon emit their respective secondary characteristic X-rays when excited by the isotope Pu238. Among them, the secondary characteristic X-rays of calcium and iron, due to their relatively higher energy compared to those of aluminum and silicon, are referred to as high-energy secondary characteristic X-rays, while those of aluminum and silicon are termed low-energy secondary characteristic X-rays. The various characteristic X-rays are amplified by a proportional counter tube to produce their respective electrical pulses. Due to differences in energy, the resulting pulse voltages also vary. These electrical pulses are filtered by a specifically designed electronic discriminator to remove the pulses generated by low-energy characteristic X-rays, leaving only the pulses produced by the characteristic X-rays of calcium and iron. Since the atomic number of calcium is 40 and that of iron is 56, the difference between them is significant, resulting in a substantial difference in the energy of their characteristic X-rays. Consequently, their electrical pulse waves do not overlap and can be measured separately. The principle of X-ray fluorescence mass analysis is based on the fact that the height of the electrical pulse is proportional to the intensity of the secondary characteristic X-rays produced by the element. The relationship between the intensity of an element's characteristic X-rays and its content is as shown in Equation (1.1):