| 摘要 |
<p>PURPOSE:To find the density of a sample based on the actual condition by finding the count value of gamma-ray pulses detected by means of a detecting sensor at every plurality of energy ranges and substituting the count value for the unknown variable indicating the moisture content of a sample to be measured of an approximate expression. CONSTITUTION:A radiation source 2 for radiating gamma-ray pulses upon a sample to be measured is put in the enclosure 1 of a surface type density measuring instrument to be put on the surface of the sample and, at the same time, a pair of detecting sensors 3 and 4 for detecting the gamma-ray pulses passed through the sample is set at different distances L1 and L2, respectively, from the source 2. The gamma-ray pulse count values of the sensors 3 and 4 are found at every plurality of energy ranges and a variable value indicating the actual moisture content of the sample is found by substituting the count values for the unknown variable indicating the moisture content of the sample of an approximate expression. In addition, when the variable value is applied to a density calculating formula, the true density of the sample can be found.</p> |
