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At the moment, inductive, capacitive, optical, and ultrasound sensors are used to measure distance to objects in the proximity range. Inductive sensors work only with metal objects, the material and [...]

Novel experimental evidence is presented for the phase heterogeneity of a thermotropic copolyester containing 50 % of p-hydroxybenzdic acid (HB). Characteristic phase morphologies accompanying spinodal decomposition in polymer blends can be detected. Fractionation and a NMR-analysis demonstrate that the copolyester contains two constituents which differ in their HB-contents.

A simple and accurate method for determining the FM noise of negative-resistance regenerative oscillators in the microwave region is the so-called direct detection system, where the FM-AM noise conversion is achieved with a discriminator, usually a high Q-factor cavity. With increasing oscillator frequency (above 30 GHz), however, it becomes increasingly difficult to obtain reliable discriminators with high Q-factors. This difficulty can be overcome by applying high-quality quasi-optical resonators for the FM-AM noise conversion.

p-type single-drift IMPATT diodes for V-band frequencies were fabricated by a single diffusion process. The diodes were packaged on a copper heatsink using quartz standoffs and investigated in a resonant cap waveguide structure. The maximum CW output power is 0.5 at 68 GHz with an efficiency of 8.7%

Oxidation of the known azetidinedione (I) yields, via the radical (II), the tetrazane (III), which is methanolized to the ring‐opened derivative (IV).