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Nondestructive techniques to measure dielectric properties of aqueous samples have become a crucial research topic for their impact on emerging biomedical applications. Accurate modeling of the dielectric behavior of biological tissues is fundamental to properly assess biomedical microwave imaging techniques. But it is also highly demanded to enable more reliable pretreatment planning for therapeutic technologies using electromagnetic fields such as hyperthermia and thermal ablation. This paper compares 2 well‐documented measuring methods based on open‐ended coaxial probe with a broadly commercialized set‐up and existing literature. Measurements were carried out across the frequency range 0.5‐4.5 GHz at 20°C on deionized water, methanol, and 2‐propanol samples. This selection of media under test is justified by their stability and existing literature on them. Moreover, their permittivity values well cover the variability range in biological tissues. This comparative study shows that the Stuchly and Stuchly method calibrated using deionized water, methanol, and open circuit conditions is a valid alternative to the commercial set‐ups available.

We propose a new time-resolved laser-induced breakdown spectroscopy (TRELIBS) system for quantitative determination of small amounts of pollutants in gas. Some experimental results showing the high resolution of the method are reported, and possible improvements of the system are discussed.

Shock waves were produced in water by directing unfocused 0.4-J, 20-ns ruby (λ=0.693 μm) or 3-J, 8-ns Nd-glass (λ=1.06 μm) laser light onto the metalized surface of a thin plastic foil. The illuminated areas were 0.35 and 2.3 cm2, respectively, corresponding to laser irradiances of 52.6 and 68.4 MW cm−2. The radial propagation velocity and the profile of the generated waves have been measured via double-exposure interferometric holography and shadowgraphy. Using the obtained values of the shock velocities and the fringe shift in the interferograms, the pressure on the shock wave front, the thickness of the compressed water layer, the laser energy consumed in producing this layer, and the time required for its formation have been calculated.

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