| 摘要 |
<p>PURPOSE:To find the density of a sample based on the actual condition by finding the count value of detected gamma-ray pulses at every plurality of energy ranges and substituting the count value for the unknown variable of an approximate expression, with the unknown variable taking the moisture content and grain size of a sample to be measured into account. CONSTITUTION:A radiation source 4 for radiating gamma-ray pulses is put in the enclosure 3 of a surface type density measuring instrument to be put on the surface of a sample to be measured and detecting sensors 5 and 6 for detecting the gamma-ray pulses passed through the sample are provided at different distances L1 and L2, respectively, from the source 4. The count values of the gamma-ray pulses detected by the sensors 5 and 6 are found at every plurality of energy ranges and the values of the first and second unknown variables respectively indicating the actual moisture content and grain size of the sample are found by substituting the count values for the first unknown variable indicating the moisture content and second unknown variable indicating the grain size of an approximate expression. In addition, when the first and second unknown variables are applied to a density calculating formula, the true density of the sample can be found.</p> |
