The greening of materials science and engineering

The field of materials science and engineering is advancing at a revolutionary pace. It is now generally recognized as being among the key emerging technological fields propelling our world societies into the twenty-first century. The driving forces for this revolutionary pace are at once social, economic, political, and technological. For example, relatively recent changes in United States federal policies in environmental control, hazardous waste management, and energy conservation along with heightened international trade competition have resulted in major changes in material processing and use patterns. These changing patterns are creating new requirements for material developments, substitutions, and associated processes. This paper traces the emergence of materials policy and technological developments through four sub-periods of history: the birth and development of engineering in the United States (1825–1900), the evolution of a national research infrastructure (1900–1945), the evolution of a national science policy (1945–1973), and the intensification of global interdependency (1973-present). Future trends in materials developments and future policy requirements are outlined. Technical Resources, of TRW, Inc., began his professional career in 1954 as a research metallurgist and reactor project engineer with General Electric Co. at the Hanford Atomic Products Operation in Richland, WA. In 1965 he joined Battelle Memorial Institute as a manager of the metallurgy research department and three years later became manager of the fuels and materials department. In 1970 Dr. Bement joined the faculty of Massachusetts Institute of Technology as professor of nuclear materials. From 1974 to 1976 he served as a member of the U.S.-U.S.S.R. Bilateral Exchange Program in Magnetohydrodynamics and was the organizer and principal investigator of the M.I.T. Fusion Technology Program. In 1976 Dr. Bement became Director of the Materials Sciences Office of the Defense Advanced Research Projects Agency and in 1979 was appointed Deputy Under-Secretary of Defense for Research and Engineering. Dr. Bement has co-authored one book, edited three books, and authored over 90 articles on materials science, energy, and defense technology. He is a Fellow of the American Nuclear Society, the American Society for Metals, and the American Institute of Chemists. In addition, he is a member of the American Institute for Mining, Metallurgical and Petroleum Engineers, and the American Society for Testing and Materials. He has received outstanding achievement awards from the Colorado Engineering Council in 1954, the Defense Advanced Research Projects Agency in 1977, and the Colorado School of Mines in 1984. In 1980 he was awarded the Distinguished Civilian Service Medal by the Secretary of Defense. He is a member of the National Academy of Engineering. Dr. Bement is chairman of the National Materials Advisory Board and a member of the Board of Army Science and Technology, the Board on Engineering Sciences, the Board on Assessment of National Bureau of Standards Programs, and the Board on Science and Technology for International Development of the National Research Council. Dr. Bement received an Engineer of Metallurgy (E. Met.) degree in 1954 from the Colorado School of Mines. He received an M.S. in Metallurgical Engineering from the University of Idaho in 1959, and a Ph.D. from the University of Michigan in 1963. He is a Lt. Colonel (ret.) in the U.S. Army Corps of Engineers. Dr. Bement and his family reside in Mayfield Village, OH.     

Comparison of Solutions of the Problems of Elasticity Theory for Different Near-Boundary Elements

We consider three types of near-boundary elements: curvilinear quadrangles and families of arcs and points, and their application to a two-dimensional problem of the static theory of elasticity with boundary conditions in displacements. The comparison of the theoretical and numerical aspects of the obtained solutions is performed. It is shown that the accuracy of evaluation of the components of the vector of displacements increases in the following cases: in the case of complete quantization of the near-boundary region (but not in the case of its partial quantization or quantization with overlapping), in the case where the numbers of arcs and points increase, and in the case of simultaneous application of different types of near-boundary elements (specifically, quadrangles and families of arcs).     

Top-Seeded Melt-Growth of YBa2Cus3Ox Crystals for Neutron Diffraction Studies

We have grown cubic centimeter-size crystals of YBa₂Cu₃O _x suitable for neutron studies, by a top-seeded melt-growth technique. Growth conditions were optimized with an eye toward maximizing phase purity. It was found that the addition of 2% Y₂BaCuO₅ and 0.5% Pt (by mass) were required to prevent melt loss and to obtain the highest crystallinity. A neutron diffraction study on a mosaic of six such crystals found that the final Y₂BaCuO₅ concentration was 5%, while other impurity phases comprised less than 1% by volume. The oxygen content was set to x = 6.5, the crystals were detwinned, and then carefully annealed to give the well-ordered ortho-II phase. The neutron study determined that 70% of the mosaic's volume was in the majority orthorhomic domain. The neutron (006) and (110) rocking curve widths were ～1° per crystal and ～2.2° for the mosaic, and the oxygen chain correlation lengths were >100 Å in the a- and b-directions and ～50 Å in the c-direction.     

The first accurate measurement of systolic and diastolic bloodpressure

Poiseuille, known for his law of fluid flow, which is the analog of Ohm's law, introduced the units (mmHg) by which we measure blood pressure by using the mercury manometer, which he described in his medical school thesis in 1828. For 50 years, mean blood pressure was all that could be measured because of the long response time of the mercury manometer. It is true that the height of the mercury column displayed pulsatile oscillations, but their amplitude was much less than that of pulse pressure. It is interesting to note that the slowly responding mercury manometer was made to display first systolic then diastolic pressure by means of an ingenious device that contained two oppositely directed check valves. It took from 1828 to 1903 for high-fidelity graphic recordings of blood pressure to appear in which systolic and diastolic pressures were believable. However, systolic and diastolic pressures were measurable since 1878 when Golz and Gaule created their ingenious valved device that permitted use of the slowly responding mercury manometer to display these pressures accurately     

高级控制系统提高巴西水电站性能

巴西的一个重要电力公司COPEL最近开发了一个水电站高级控制系统，这是在电力部门经受重大变革时期，提高水电竞争力的里程碑。     

The role of occlusion in the perception of depth, lightness, and opacity.

A theory is presented that explains how the visual system infers the lightness, opacity, and depth of surfaces from stereoscopic images. It is shown that the polarity and magnitude of image contrast play distinct roles in surface perception, which can be captured by 2 principles of perceptual inference. First, a contrast depth asymmetry principle articulates how the visual system computes the ordinal depth and lightness relationships from the polarity of local, binocularly matched image contrast. Second, a global transmittance anchoring principle expresses how variations in contrast magnitudes are used to infer the presence of transparent surfaces. It is argued that these principles provide a unified explanation of how the visual system computes the 3-D surface structure of opaque and transparent surfaces. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intraseptal scopolamine has differential effects on Pavlovian eye blink and heart rate conditioning.

Evaluated the effects of intraseptal scopolamine hydrobromide (40 μg) injections on Pavlovian (classical) conditioning, with tones used as the CS and a periorbital electric shock train as the UCS, using New Zealand albino rabbits. Eyeblink (EB) and heart rate (HTR) CRs were concomitantly recorded. Although injections of scopolamine into the medial septum impaired the acquisition of the Pavlovian conditioned eyelid reflex, these injections enhanced the magnitude of accompanying Pavlovian conditioned HTR decelerations. However, scopolamine applied to the lateral septal area had no effect on EB conditioning, relative to the vehicle; like medial injections, scopolamine also enhanced the magnitude of the accompanying HTR decelerations. Results are compatible with those of previous investigations indicating that medial septal dysfunction impairs somatomotor conditioning but leaves autonomic conditioning intact and that septal dysfunction produces a parasympathetic bias of the cardiovascular system. (49 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)