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Engineering of the electrocapillary behavior of electrolyte droplets on thin fluoropolymer films

Published in:
Langmuir, Vol. 22, No. 13, 20 June 2006, pp. 5690-5696.

Summary

This study presents methods for engineering the electrocapillary behavior of fluoropolymer surfaces through the use of surfactants and an external insulating liquid. By the scaling of the appropriate surface energies, electrocapillary behavior is obtained at a record low voltage, with contact angle changes in excess of 100[degrees] at 4 V. A consistent description of electrocapillary saturation is presented, identifying three separate regimes: breakdown, thermodynamic instability, and relaxation. Methods for identifying and mitigating some of the saturation behaviors are discussed. Finally, the parameters influencing the observed voltage of zero charge are summarized.
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Summary

This study presents methods for engineering the electrocapillary behavior of fluoropolymer surfaces through the use of surfactants and an external insulating liquid. By the scaling of the appropriate surface energies, electrocapillary behavior is obtained at a record low voltage, with contact angle changes in excess of 100[degrees] at 4 V...

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A high-power MEMS electric induction motor

Published in:
J. Microelectromech. Syst., Vol. 13, No. 3, June 2004, pp. 465-471.

Summary

An electric induction micromotor with a 4-mm-diameter rotor was designed and built for high-power operation. Operated at partial actuating voltage, the motor has demonstrated an air gap power in excess of 20 mWand torque of 3 5 Nmat speeds in excess of 55 000 rpm. Operation at higher power and speed was limited by bearing stability at higher rotational speeds. The device builds on an earlier micromotor demonstrated by Frechette et al. The high power of the present motor is enabled by its low-loss, high-voltage electric stator, which also offers improved efficiency. The development of this electromechanical device is an important enabling step not only for watt-scale micromotors, but also for the development of microelectric generators. This paper presents the motorαs design, the fabrication process that was created to meet its stringent design requirements, and its performance to date.
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Summary

An electric induction micromotor with a 4-mm-diameter rotor was designed and built for high-power operation. Operated at partial actuating voltage, the motor has demonstrated an air gap power in excess of 20 mWand torque of 3 5 Nmat speeds in excess of 55 000 rpm. Operation at higher power and...

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A photomixer local oscillator for a 630-GHz heterodyne receiver

Published in:
IEEE Microw. Guid. Wave Lett., Vol. 9, No. 6, June 1999, pp. 245-7.

Summary

A photomixer local oscillator (LO) operating at the 630-GHz difference frequency of two laser diodes was successfully demonstrated with a heterodyne detector based on a niobium superconducting tunnel junction. The low-temperature-grown GaAs photomixer generated 0.20 uW in the input spatial mode of the receiver. Using the photmixer LO, the double-sideband noise temperature of the receiver was 331 K - in good agreement with the 323-K noise temperature obtained when a multiplied Gunn oscillator generating 0.25 uW was substituted for the photomixer.
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Summary

A photomixer local oscillator (LO) operating at the 630-GHz difference frequency of two laser diodes was successfully demonstrated with a heterodyne detector based on a niobium superconducting tunnel junction. The low-temperature-grown GaAs photomixer generated 0.20 uW in the input spatial mode of the receiver. Using the photmixer LO, the double-sideband...

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