Tin dioxide sol-gel derived thin films deposited on porous silicon

Undoped and Sb-doped SnO2 sol¿gel derived thin films have been prepared for the first time from tin (IV) ethoxide precursor and SbCl3 in order to be utilised for gas sensing applications where porous silicon is used as a substrate. Transparent, crack-free and adherent layers were obtained on different types of substrates (Si, SiO2/Si). The evolution of the Sn¿O chemical bonds in the SnO2 during film consolidation treatments was monitored by infrared spectroscopy. By energy dispersive X-ray spectroscopy performed on the cross section of the porosified silicon coupled with transmission electron microscopy, the penetration of the SnO2 sol¿gel derived films in the nanometric pores of the porous silicon has been experimentally proved

The Microcomputer Catalyst

Microcomputer it is a word many of us first heard only a couple of years ago. Yet the technology this word represents holds promise of tremendous change. The changes catalyzed by microcomputing and its associated technologies may alter the fundamental nature of information handling in all its forms. This, of course, means that libraries and information centers will be profoundly affected by this new technology. This paper attempts to indicate some possible directions of the changes prompted by microcomputing technology. However, these ideas are offered only with the disclaimer that technology in this area is developing so rapidly that no one involved in computing can fully understand its implications. Hardware designers and software engineers involved in microcomputing are themselves still attempting to discern the values and possible uses of microcomputers. The only "given" most would agree upon is the recognition that microcomputers will alter the basic manner in which computers are used and viewed in our society.published or submitted for publicatio

Women, Solidarity & the Global Factory

[Excerpt] For many of us who are concerned with international labor issues, a new image has come to represent our collective understanding of the global economy. It is an image of women in Third World nations toiling under sweatshop conditions in huge assembly plants owned by U.S.-based transnational corporations (TNCs). Yet what does international solidarity really mean in practice? Who does it include, and how? From a U.S. standpoint, if so many women workers are not organized into unions, how can they be included in international networks? If their voices are not heard, what can these networks hope to accomplish? This article explores these questions by looking at the experience of several groups in promoting international communication among women workers in the nonunion sector. It is excerpted from The Global Factory: An Organizing Guide for a New Economic Era. The complete publication, developed by the American Friends Service Committee, surveys the efforts of many different kinds of groups, inside and outside the trade union movement, to build international labor networks

On the Angular Dependence of InP High Electron Mobility Transistors for Cryogenic Low Noise Amplifiers in a Magnetic Field

The InGaAs-InAlAs-InP high electron mobility transistor (InP HEMT) is the preferred active device used in a cryogenic low noise amplifier (LNA) for sensitive detection of microwave signals. We observed that an InP HEMT 0.3-14GHz LNA at 2K, where the in-going transistors were oriented perpendicular to a magnetic field, heavily degraded in gain and average noise temperature already up to 1.5T. Dc measurements for InP HEMTs at 2K revealed a strong reduction in the transistor output current as a function of static magnetic field up to 14T. In contrast, the current reduction was insignificant when the InP HEMT was oriented parallel to the magnetic field. Given the transistor layout with large gate width/gate length ratio, the results suggest a strong geometrical magnetoresistance effect occurring in the InP HEMT. This was confirmed in the angular dependence of the transistor output current with respect to the magnetic field. Key device parameters such as transconductance and on-resistance were significantly affected at small angles and magnetic fields. The strong angular dependence of the InP HEMT output current in a magnetic field has important implications for the alignment of cryogenic LNAs in microwave detection experiments involving magnetic fields

Realization of a four-electrode liquid crystal device with full in-plane director rotation

A liquid crystal device with micrometer-scale hexagonal electrodes has been fabricated and characterized. By using weak anchoring at the liquid crystal interfaces, the orientation of the director is completely governed by the applied electric fields. The appropriate voltage waveforms applied to electrodes allow the director in the liquid crystal layer to be rotated in the plane parallel to the substrates over large angles, exceeding 180 °. This paper is a technological and experimental verification of an earlier proposed device concept. © 2007 IEEE

Process and machine system development for the forming of miniature/micro sheet metal products

This paper reports on the current development of the process for the forming of thin sheet-metal micro-parts (t < 50µm) and the corresponding machine system which is part of the research and technological development of an EU funded integrated project - MASMICRO ("Integration of Manufacturing Systems for the Mass-Manufacture of Miniature/Micro-Products" (/www.masmicro.net/). The process development started with qualification of the fundamentals related to the forming of thin sheet-metals in industrial environment, for which a testing machine and several sets of the testing tools were developed. The process was further optimised, followed by new tool designs. Based on the experience gained during the process development, a new forming press which is suitable for industrial, mass-customised production, has been designed

Two-Dimensional Spintronic Circuit Architectures on Large Scale Graphene

Solid-state electronics based on utilizing the electron spin degree of freedom for storing and processing information can pave the way for next-generation spin-based computing. However, the realization of spin communication between multiple devices in complex spin circuit geometries, essential for practical applications, is still lacking. Here, we demonstrate the spin current propagation in two-dimensional (2D) circuit architectures consisting of multiple devices and configurations using a large area CVD graphene on SiO2/Si substrate at room temperature. Taking advantage of the significant spin transport distance reaching 34 {\mu}m in commercially available wafer-scale graphene grown on Cu foil, we demonstrate that the spin current can be effectively communicated between the magnetic memory elements in graphene channels within 2D circuits of Y-junction and Hexa-arm architectures. We further show that by designing graphene channels and ferromagnetic elements at different geometrical angles, the symmetric and antisymmetric components of the Hanle spin precession signal can be remarkably controlled. These findings lay the foundation for the design of complex 2D spintronic circuits, which can be integrated into efficient electronics based on the transport of pure spin currents

Observation of Spin Hall Effect in Weyl Semimetal WTe2 at Room Temperature

Discovery of topological Weyl semimetals has revealed the opportunities to realize several extraordinary physical phenomena in condensed matter physics. Specifically, these semimetals with strong spin-orbit coupling, broken inversion symmetry and novel spin texture are predicted to exhibit a large spin Hall effect that can efficiently convert the charge current to a spin current. Here we report the direct experimental observation of a large spin Hall and inverse spin Hall effects in Weyl semimetal WTe2 at room temperature obeying Onsager reciprocity relation. We demonstrate the detection of the pure spin current generated by spin Hall phenomenon in WTe2 by making van der Waals heterostructures with graphene, taking advantage of its long spin coherence length and spin transmission at the heterostructure interface. These experimental findings well supported by ab initio calculations show a large charge-spin conversion efficiency in WTe2; which can pave the way for utilization of spin-orbit induced phenomena in spintronic memory and logic circuit architectures

The Use of Microtechnology to Quantify the Peak Match Demands of the Football Codes: A Systematic Review.

BACKGROUND: Quantifying the peak match demands within the football codes is useful for the appropriate prescription of external training load. Wearable microtechnology devices can be used to identify the peak match demands, although various methodologies exist at present. OBJECTIVES: This systematic review aimed to identify the methodologies and microtechnology-derived variables used to determine the peak match demands, and to summarise current data on the peak match demands in the football codes. METHODS: A systematic search of electronic databases was performed from earliest record to May 2018; keywords relating to microtechnology, peak match demands and football codes were used. RESULTS: Twenty-seven studies met the eligibility criteria. Six football codes were reported: rugby league (n = 7), rugby union (n = 5), rugby sevens (n = 4), soccer (n = 6), Australian Football (n = 2) and Gaelic Football (n = 3). Three methodologies were identified: moving averages, segmental and 'ball in play'. The moving averages is the most commonly used (63%) and superior method, identifying higher peak demands than other methods. The most commonly used variables were relative distance covered (63%) and external load in specified speed zones (57%). CONCLUSION: This systematic review has identified moving averages to be the most appropriate method for identifying the peak match demands in the football codes. Practitioners and researchers should choose the most relevant duration-specific period and microtechnology-derived variable for their specific needs. The code specific peak match demands revealed can be used for the prescription of conditioning drills and training intensity