Non-linear effects occurring in photothermal microscopes based on principle of photothermal radiometry are studied as a hnction of the laser power and of the modulation frequency. For stainless steel, a second harmonic component of up to 11 % of the hndamental amplitude is found. Phase shifts of up to 20 degrees are observed as a hnction of the modulation frequency. The nonlinearity is mainly d...

ultrasonic testing (ut), a nondestructive testing (ndt) method, is under development for quality determination of agricultural products, although it has long been used in the food industry. determination and measurement of product quality are important in modern agricultural research. noninvasive/nondestructive quality determination is a novel aspect of the postharvest process in which paramete...

natural radionuclides present in soil as well as certain anthropogenic radionuclides released to the environment are the major contributors to terrestrial outdoor exposures. in the assessment of human exposures from environmental radioactivity, besides the conventional method of soil and vegetation sampling combined with laboratory based analyses of environmental media, the other choice would b...