Agricultural Research Journal

Hygroscopic composite materials like wood keep on changing their internal moisture contents according to the surrounding atmosphere which in turn result in varying their physical as well as mechanical properties. The present study describes the use of gamma radiation techniques to determine the mass attenuation coefficients of Eucalyptus species and Pinus roxburghii wood samples at various moisture levels using ¹³⁷Cs radioactive gamma source and the variation of these mass attenuation coefficients with relative moisture content of the selected wood samples. The moisture content of the samples was varied by keeping the samples in an electric oven for fixed durations. The measured mass attenuation coefficients were plotted against relative moisture content of the samples and a linear trend was obtained. These mass attenuation coefficients were found to be increasing with decreasing moisture content in the samples indicating that conclusion benefit i.e., the mass attenuation coefficient was minimum for completely wet state and maximum for oven dry state (state where density of the sample becomes constant) of the samples.