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High-resolution diffraction experiments of Fe90Sc10 nanoglasses and rapidly quenched metallic glasses as reference materials have been performed using high-energy x-rays with a wavelength of 0.21 Å from a synchrotron radiation source. Nanoglasses are amorphous alloys with a significant fraction of interfaces on the nanometer scale. The short- and intermediate-range orders of a nanoglass are different from the well known amorphous materials produced by rapid quenching from the melt. These structural modifications have significant influence on the physical properties. In this paper, the short- and intermediate-range orders of the nanoglass Fe90Sc10 and the reference metallic glass Fe90Sc10 alloy prepared by rapid quenching are discussed. [ABSTRACT FROM AUTHOR]

Ultrasound current source density imaging (UCSDI) potentially transforms conventional electrical mapping of excitable organs, such as the brain and heart. For this study, we demonstrate volume imaging of a time-varying current field by scanning a focused ultrasound beam and detecting the acoustoelectric (AE) interaction signal. A pair of electrodes produced an alternating current distribution in a special imaging chamber filled with a 0.9% NaCl solution. A pulsed 1 MHz ultrasound beam was scanned near the source and sink, while the AE signal was detected on remote recording electrodes, resulting in time-lapsed volume movies of the alternating current distribution. [ABSTRACT FROM AUTHOR]

Physics-based models of organic field-effect transistors (OFETs) which can be used for computer-aided simulation of organic integrated circuits were investigated. For this purpose hybrid OFETs with poly(3-hexylthiophene-2,5-diyl) as the semiconductor were fabricated and characterized. The differential drain-source resistance reveals the need for a unified consideration of a gate-voltage-dependent mobility and of the depletion effect. We avoid neglecting the capacitance of the insulator and the semiconductor which would have otherwise introduced restrictions. The analytic modeling yields a compact static equivalent circuit diagram. [ABSTRACT FROM AUTHOR]

The possibility to synthesize bulk amorphous materials with an internal nanostructure-nanoglasses-leads to yet another class of materials potentially with modified properties. Here, evidence is presented that the nanoglass model system Fe90Sc10 exhibits enhanced magnetic properties: it is shown that this nanoglass (prepared by cold compaction of glassy nanospheres) is a ferromagnet at ambient temperature although the isolated nanospheres are paramagnetic. Structural studies reveal that it consists of glassy nanospheres connected by regions with reduced atomic density. The ferromagnetism is explained by the presence of such regions of low atomic density. [ABSTRACT FROM AUTHOR]

A correction to the article "Static model for organic field-effect transistors including both gate-voltage-dependent mobility and depletion effect," published in December 8, 2006 is presented.