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The efficiency of multi-watt ultraviolet radiation generation by harmonics processes in β-BaB2O4 (BBO) can be improved by reducing thermal dephasing. The dephasing arises from local heating of BBO by the linear absorption of green (second harmonic) and ultraviolet (fourth harmonic) radiation by crystal defects that are induced by two-photon absorption of high peak power ultraviolet radiation. Such absorption can be reduced by decreasing the repetition rate to ∼1 kHz to allow the defects to decay between the laser pulses and/or heating BBO crystal to 150–200 °C to increase the decay rate of the induced defects.

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Measuring the moisture content of forage crops is important to produce high-quality silage. Oven-drying methods are currently the most popular methods used for measuring the moisture content of forage crops. However, these methods require the destruction of silage materials and are time-consuming. Methods for rapidly predicting the moisture content of forage crops have been developed, such as DC resistance measurement, near-infrared reflectance spectroscopy (Amari & Abe, 1997), radiofrequency capacitance measurement (Kawaide, Kojima, & Tachibana, 2012) and time domain reflectometry measurement (Hattori et al., 2015) techniques. These methods utilize the difference in the permittivity between wet and dry forage crops and require the placement of a sensor probe either into or on the surfaces of the silage materials. Consequently, such sampling of silage materials from silos requires tearing down or destroying covering films, exposing the materials to aerobic conditions. Even techniques that