Deposition and Properties of Superconducting MgB2 Thin Films

The recently discovered superconductor MgB₂ with T _c at 39 K has great potential in superconducting electronics. In this paper, we review the deposition techniques used for MgB₂ thin films in the light of a thermodynamic study of the Mg-B system with the calculation of phase diagrams (CALPHAD) modeling technique. This thermodynamic study identifies a growth window in the pressure–temperature phase diagram, in which the magnesium pressure is very high for likely in situ growth temperatures. A Hybrid Physical–Chemical Vapor Deposition (HPCVD) technique that successfully achieves such a high Mg pressure is shown to produce in situ epitaxial MgB₂ thin films with bulk superconducting properties.     

Risk Factors for Course of Posttraumatic Stress Disorder Among Vietnam Veterans: A 14-Year Follow-Up of American Legionnaires.

Risk factors affecting the course of posttraumatic stress disorder (PTSD) are poorly understood. As part of a larger study on characterizing exposure to herbicides in Vietnam, the authors investigated this issue in a random sample of 1,377 American Legionnaires who had served in Southeast Asia during the Vietnam War and were followed over a 14-year period. High combat exposure, perceived negative community attitudes at homecoming, minority race, depression symptoms at Time 1, and more anger at Time 1 predicted a more chronic course. Community involvement at Time 1 was protective and associated with decreased risk at Time 2. Discomfort in disclosing Vietnam experiences was associated with an increased risk for developing PTSD but did not predict its course. Combat exposure predicted PTSD course more strongly than any other risk factor. Findings suggest recovery from PTSD is significantly influenced by perceived social support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

一种基于GE90-30PLC的飞剪自动控制系统

本文介绍了调整线材轧线精轧机前专用于切头的启停式飞剪的自动控制系统。该系统以GE90—30PLC为控制核心，辅以热金属HMD、光电编码器等元件，能很好地完成飞剪的剪切及定位。其中着重阐述了飞剪控制中各个重要参数的计算原理和方法。     

广泛应用机器人技术是提高连铸安全性的重要步骤

1前言及历史背景 为避免钢水造成燃烧或破碎引起对人体的可能伤害,必须对连铸平台的平面布置进行分析.     

Isotope Exchange of Azidothymidine with Tritium

The following modes of isotope exchange of azidothymidine (3'-azido-3'-deoxythymidine) with tritium were studied: solid- and liquid-phase isotope exchange with gaseous tritium and isotope exchange in solution with tritium water. Catalytic reactions of azidothymidine with gaseous tritium in solution result in virtually complete reduction of the azido group to amino group. This reduction also occurs in the course of solid-phase catalytic hydrogenation; the yield of 3'-amino-3'-deoxythymidine ranges from 20 to 70%. The molar radioactivity of tritium-labeled azidothymidine prepared by solid-phase catalytic isotope exchange with gaseous tritium and by isotope exchange in solution with tritium water does not exceed 0.5 Ci mmol^{- 1}.     

One Hundred Years of Social Psychology Quantitatively Described.

This article compiles results from a century of social psychological research, more than 25,000 studies of 8 million people. A large number of social psychological conclusions are listed alongside meta-analytic information about the magnitude and variability of the corresponding effects. References to 322 meta-analyses of social psychological phenomena are presented, as well as statistical effect-size summaries. Analyses reveal that social psychological effects typically yield a value of r equal to .21 and that, in the typical research literature, effects vary from study to study in ways that produce a standard deviation in r of .15. Uses, limitations, and implications of this large-scale compilation are noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermodynamics of Superfluidity

A new superfluid specific additive integral of motion is found. This facilitates investigation of the general thermodynamic equilibrium conditions of a superfluid. The analysis is performed in an extended space of thermodynamic variables containing (along with the usual thermodynamic coordinates such as pressure and temperature) superfluid velocity and momentum density. The equilibrium stability conditions lead to thermodynamic inequalities which replace the Landau superfluidity criterion at finite temperatures.     

Static and Dynamic Spins in Superconducting La2−x Sr x CuO4: The Risø Years

One important area of modern condensed matter research is the investigation of the nature of the superconducting cuprates. Much progress in this field has been obtained with the technique of neutron scattering. We here present a review of neutron scattering studies of the high-temperature superconductor La_2?xSr_xCuO₄, performed at Risø National Laboratory. We review the work on the mapping of the incommensurate spin fluctuations, the investigation of the gap in the fluctuation spectrum, the magnetic properties of the vortices appearing in an applied field, and the quantum critical behaviour of the system. We discuss our findings in the light of results of neutron scattering from other groups, on other cuprate systems, and results from other experimental methods, e.g. NMR, μSR, STM, X-ray diffraction, and ARPES. We end with a discussion on the implications of the experimental results for the progress in the general understanding of high-temperature superconductivity. PACS numbers: 61.12.Ex, 74.20.Mn, 74.72.Dn, 75.25.+z, 78.70.Nx.     

Absence makes the adaptations grow fonder: Proportion of time apart from partner, male sexual psychology, and sperm competition in humans (Homo sapiens).

Sperm competition occurs when the sperm of multiple males concurrently occupy the reproductive tract of a female and compete to fertilize an egg. We used a questionnaire to investigate psychological responses to the risk of sperm competition for 237 men in committed, sexual relationships. As predicted, a man who spends a greater (relative to a man who spends a lesser) proportion of time apart from his partner since the couple's last copulation reported (a) greater sexual interest in his partner, (b) greater distress in response to his partner's sexual rejection, and (c) greater sexual persistence in response to his partner's sexual rejection. All effects were independent of total time since the couple's last copulation and the man's relationship satisfaction. Discussion addresses limitations of the current research and situates the current results within the broader comparative literature on adaptation to sperm competition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Radiation-induced hydrogen yield from silicon bombarded with 710-MeV bismuth ions

The behavior of hydrogen in solids under the action of intense ionizing radiation is of importance in solving numerous problems of materials science for the nuclear and thermonuclear power industry, spacecraft engineering, hydrogen energetics, and microelectronics. Experimental results are presented that provide evidence of the radiation-induced yield of hydrogen from single crystal silicon bombarded with 710-MeV bismuth ions.