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Silver describes the implementation of a monitoring system using an open-source software package to improve the availability of services and reduce the response time when troubles occur. He provides a [...]

YBa2Cu3O7(Y123) thin films were grown by pulsed laser deposition (PLD) on YSZ (100), SrTiO3 (100), and LaAlO3 (100) single crystal substrates. Prior to the film deposition, a discontinuous layer of Ag nano-dots was deposited on the substrates. The Y123 films grown on such surfaces modified with Ag nano-dots were characterized by Atomic Force Microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM), AC susceptibility and DC magnetization. The effects of the density of Ag nano-dots, which was controlled by the numbers of PLD shots, on the microstructures and resultant critical current density Jc have been studied systematically. Results showed that at fixed physical deposition conditions Jc increased monotonically with number of Ag shots, n, for films grown on both STO and LAO substrates. At 77 K, the Jc increased from 106 to 3.2 × 10° A/cm² for LAO and from 8 × 105 to 3.5 × 106 A/cm² for STO as n increased from 0 to 150. At 5 K, the enhancement of Jc was approximately four times at both low and high fields. However, for films grown on YSZ substrate, Jc increased from 2 × 105 to 2 × 106 A/cm² as Ag shots increased from 0 to 30, and decreased to 9 × 105 for n ≥ 60. Detailed microstructure investigations indicated that the crystallinity and ab alignment gradually improved as the number of Ag-nano-dots increased. [ABSTRACT FROM AUTHOR]

A large magnetoresistive (MR) effect was observed in Bi2212 in which USr2CaO6 was added in a proportion of 6 wt%. The resistivity of melt-textured (MT) Bi2212 + 6 wt% USr2CaO6 possess a high sensitivity to applied dc fields, as compared to pure Bi2212, in particular at low fields, below 3 T, and in a temperature range between 45 and 85 K. In this temperature range, the MR effects of MT Bi2212 + 6 wt% USr2CaO6 display a maximum that may be tuned to a particular temperature within the above range, by changing the amount of added non-superconducting compound. X-ray results show that during the melt-texturing process of this mixture, the USr2CaO6 phase is stable and the reaction with Bi2212 matrix is minimal, in spite of a small decrease in the superconducting transition temperature. A cryogenic sensor was build and tested at 77 K in low fields. It shows high sensitivity and no hysteresis of resistivity when the applied field was cycled between 0 and 1 T. [ABSTRACT FROM AUTHOR]

The processing, microstructures and properties of La0.7Sr0.3Mn1−xZnxO3 perovskite manganite, with x=0, 0.1, 0.2, and 0.3 have been investigated. X-ray diffraction, scanning electron microscopy (SEM) and other characterisation methods were used to study the relations of microstructure and properties. The X-ray powder diffraction results show a single phase for the 0 region that confirms the zinc incorporation into the Mn site. The SEM images with magnification 1500× indicate that the studied system is a single phase. The transport measurements show decreasing of insulator to metal transition temperature, Tt, with increasing the zinc concentration on the Mn site, while the resistivity increases with increasing the zinc doping level for 0 The maximum resistivities are found at 380 and 160 K, respectively.The PPMS measurements show that the magnetisation value is greatest for x=0.1 and drastically decrease for the parent material, as well as with increasing the zinc doping concentration above 20%, when the compound changes from ferromagnetic to paramagnetic. The paramagnetic to ferromagnetic transition temperature variations, Tc, agrees with the insulator to metal variations, Tt, from the transport measurements for the parent and 10% doped material. For zinc doping levels above 20%, the behavior of the studied system changes from ferromagnetic to paramagnetic. [Copyright &y& Elsevier]

The processing, microstructures and properties of La0.7Sr0.3Mn1-xZnxO3 perovskite manganite, with x=0, 0.1, 0.2, and 0.3 have been investigated. X-ray diffraction, scanning electron microscopy (SEM) and other characterisation methods were used to study the relations of microstructure and properties. The X-ray powder diffraction results show a single phase for the 0c, agrees with the insulator to metal variations, Tt, from the transport measurements for the parent and 10% doped material. For zinc doping levels above 20%, the behavior of the studied system changes from ferromagnetic to paramagnetic. [ABSTRACT FROM AUTHOR]

Radiographic examination of soft tissue extremity masses is frequently inconclusive. In 18 patients with normal or nonspecifically abnormal radiographs, gray scale ultrasonography provided useful additional information. It was possible to distinguish fluid collections from solid masses, and recurrent venous thrombosis from hematoma in anticoagulated patients. Occasionally, specific diagnoses were suggested on the basis of ultrasonic morphologic characteristics. Diagnoses included soft tissue neoplasms, hematomas, aneurysms, synovial cysts, abscesses, and a lymphocele. Ultrasonically guided percutaneous needle aspiration was diagnostic to two cases. Features of differential diagnostic value relative to extremity solid masses and fluid collections are discussed. Ultrasonography is useful in evaluating these soft tissue masses. [ABSTRACT FROM AUTHOR]