No abstract

No abstract

No abstract

The new convenient method for the synthesis of high molecular weight aromatic poly(1,3,4‐oxadiazole)s (PODs) has been proposed. These polymers were prepared by “one‐pot” procedure from dicarboxylic acid and hydrazine's salt (sulfate, phosphate) or dicarboxylic acid dihydrazides. The mixture of ionic liquid and triphenyl phosphite was used both as a solvent and condensing agent. The polycyclization occurred at a sufficiently low temperature of 210 °C for 2–5 h and resulted in obtaining film‐forming PODs having inherent viscosities up to 0.9 dL/g and good thermal stability. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 380–394, 2006

Although the role of the periodic errors of optical heterodyne interferometers in displacement measurements is fairly well understood, their influence on the calibration of other types of displacement sensor does not seem to be studied as extensively. We have performed a careful analysis of the role of these errors on the calibration of a capacitance displacement sensor, which is integrated into a linear piezoelectric transducer for nanometrology applications over displacement ranges in the sub-micrometre range.Assuming a linear dependence of the output voltage of the capacitance displacement sensor on the displacement it was found analytically that periodic interferometer errors lead to a decaying oscillation of the sensor sensitivity as the displacement range used in the calibration increases. For use of a double path interferometer with a polarization mixing amplitude of 0.5 nm and a polarization mixing wavelength of 79 nm, deviations of sensor sensitivity of 0.3% for a range of 0.2 µm and 0.029% for a range of 1 µm were estimated. The pronounced oscillations of the sensor's sensitivity over very small displacement ranges as predicted by the theoretical description were verified experimentally.