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Single-crystal Ni(sub2)MnGa exhibits an almost 0.2% strain under a magnetic field of 8 kOe at -8 degrees C. A narrow band of compositions had a range of Curie temperatures and martensitic transformation temperatures, Tc and To, expanding to above room temperature. Compressive stress-strain characteristics were examined in samples with To below room temperature.

Abstract: In the application of contact glue layer for semiconductor devices, a nitrogen/hydrogen (N2/H2) plasma treatment is usually used to reduce the amount of C and O impurities of metallorganic chemical vapor deposition titanium nitride (MOCVD–TiN) films. This study found that the sheet resistance of as-deposited MOCVD–TiN film without N2/H2 plasma treatment dramatically increased with exposure time due to moisture adsorption. Increasing plasma treatment power and time was able to retard the increase in sheet resistance. From residue gas analysis at 200°C, it was found that the amount of H2O outgases from the MOCVD–TiN films decreased with increasing plasma treatment power and time. TEM images reveal that the surface of the MOCVD–TiN films became compact as it received more plasma treatment energy, making it difficult for the external moisture to diffuse into and react with the MOCVD–TiN films. [Copyright &y& Elsevier]

Abstract: The optical properties of GaAs1−x Sb x (5.9%≤ x ≤9.7%) layers grown on GaAs substrates by gas-source molecular beam epitaxy were characterized by photoreflectance (PR) and piezoreflectance (PzR). Identification of conduction to heavy-hole (HH) band and conduction to light-hole (LH) band transitions originated from the strained induced valence band splitting have been achieved by comparing the relative intensities of PR and PzR spectra. The results indicate increases of the valence band splitting with increasing of Sb content. The temperature dependences of near band edge transition energies were analyzed using Varshni and Bose–Einstein expressions in the temperature range from 15 to 300K. The parameters that describe the temperature variations of the near band edge transition energies and broadening function were evaluated and discussed. [Copyright &y& Elsevier]

Electric power, sufficient for many in vivo applications, can be transmitted wirelessly from a small external solenoid (filled with a soft magnetic core), to a novel, magnetoelectric (ME) receiver a few centimeter (cm) inside the body. The ME receiver is a sandwich of electroactive (e.g., piezoelectric) material bonded between two magnetostrictive layers. The electroactive layer may be poled in its plane so that it can function in the stronger g33 mode (induced voltage parallel to the direction of principal magnetostrictive stress). Preliminary experimental results indicate that a 7 cm long ferrite-filled solenoid (NI ap 122 Amp-turns) producing an RMS magnetic field of order 1600 A/m (20 Oe) at the ME receiver (of volume 0.1 cm3) 3 cm from the field source, generates in the ME receiver a power of 200 mW (2 W/cm3). The receiver, in turn, generates a power of 160 mW. [ABSTRACT FROM PUBLISHER]

The effect of fluoxetine on Ca2+ signaling in Madin-Darby canine kidney (MDCK) cells was investigated by using fura-2 as a Ca2+ probe. Fluoxetine increased [Ca2+]i concentration-dependently between 5 µM and 200 µM with an EC50 value of 40 µM. The response was reduced by external Ca2+ removal by 30%–40%. In Ca2+-free medium pretreatment with 1 µM thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ pump, abolished 100 µM fluoxetine-induced Ca2+ release. Addition of 3 mM Ca2+ to Ca2+-free medium increased [Ca2+]i when cells were pretreated with 100 µM fluoxetine. Suppression of 1,4,5-trisphosphate (IP3) formation by 2 µM U73122 (a phospholipase C inhibitor) did not affect 100 µM fluoxetine-induced Ca2+ release. Fluoxetine (5–100 µM) also increased [Ca2+]i in neutrophils, prostate cancer cells and bladder cancer cells from human and rat glioma cells. [ABSTRACT FROM AUTHOR]

Presents an abstract of the paper `Magnetic-Field-Induced Strain in Ni2MnGa Shape-Memory Alloy,' presented by K. Ullakko, J.K. Huang, et al, at the American Institute of Physics' 1997 Conference on Magnetism and Magnetic Materials.