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Sample records for neutronen mit materie

  1. Von Donuts und Zucker: Mit Neutronen biologische Makromoleküle erforschen

    NASA Astrophysics Data System (ADS)

    May, Roland P.

    2003-05-01

    Für die Erforschung von Biomolekülen bieten Neutronen einzigartige Eigenschaften. Vor allem ihre unterschiedliche Wechselwirkung mit dem natürlichen Wasserstoff und seinem schweren Isotop Deuterium ermöglicht tiefe Einblicke in Struktur, Funktion und Dynamik von Proteinen, Nukleinsäuren und Biomembranen. Bei vielen Fragestellungen zur Strukturaufklärung gibt es kaum oder keine Alternative zum Neutron. Das Institut Laue-Langevin trägt Bahnbrechendes zum Erfolg der Neutronen-Methoden in der Biologie bei.

  2. MIT Orients Course Materials Online to K-12

    ERIC Educational Resources Information Center

    Cavanagh, Sean

    2008-01-01

    Many science and mathematics educators across the country are taking advantage of a Web site created by the Massachusetts Institute of Technology (MIT), the famed research university located in Cambridge, Massachusetts, which offers free video, audio, and print lectures and course material taken straight from the school's classes. Those resources…

  3. Kommunikationsschulung mit englischen Werbetexten (Communication Training Using English Advertising Material)

    ERIC Educational Resources Information Center

    Thiering, Christian

    1975-01-01

    Using English airline advertisements, the article shows how, at Secondary Grade 2, such material can be used to encourage active communication by the students. Advertising material is found more productive than traditional text analysis. (Text is in German.) (IFS/WGA)

  4. Designing Materials for the Language Lab of the Future: An Overview of the MIT Athena Language Learning Project.

    ERIC Educational Resources Information Center

    Kramsch, Claire; And Others

    1985-01-01

    Details the current status, the future plans and the reasoning behind a five-year, campus-wide educational experiment for the integration of computers into the foreign language curriculum at MIT. The project is to use artificial intelligence in natural processing and to include interactive video and interactive audio components. (Author/SED)

  5. MIT: Shaping the Future.

    ERIC Educational Resources Information Center

    Manning, Kenneth R., Ed.

    This book provides 16 essays by faculty and staff of the Massachusetts Institute of Technology (MIT) concerning what MIT is like today and offering a guide to its possible future. Emphasis is placed on local, national, and global issues, providing a current sampling of the state of concerns and opinions around MIT. Topics include the question of…

  6. MIT's 3.091 and NSDL Materials Digital Library: Investigating the Role of Digital Libraries in Freshmen Introductory Science Courses with No Lab Component

    NASA Astrophysics Data System (ADS)

    Sadoway, Donald; Bartolo, Laura

    2005-03-01

    One example of the reality facing science educators is the practical impossibility of providing meaningful laboratory experience in large introductory undergraduate science courses. The Materials Digital Library (MatDL), as part of the National Science Foundation (NSF) National Science Digital Library (NSDL) program, investigates issues associated with the delivery of content in materials science and its cognate areas. The focus of the current work is to investigate the feasibility of using data archived in digital libraries to provide freshmen in large introductory science classes a virtual laboratory experience that meets many of the educational objectives of classical laboratory offerings. Also, the question of scalability and broader applicability, e.g., to freshman physics, is under study. The results of a new pilot project launched this academic year will be reported. The virtual laboratory is associated with ``Introduction to Solid State Chemistry 3.091,'' a course that over half the freshman class at MIT choose to satisfy the chemistry requirement but which lacks a laboratory component.

  7. Kommunikation mit Mitarbeitern

    NASA Astrophysics Data System (ADS)

    Spychala, Anne; Fleischmann, Jürgen

    Kommunikation ist der Austausch von Nachrichten und Informationen zwischen Mitarbeitern eines Unternehmens (O'Hair et al. 1997). Dieser Austausch kann persönlich, aber z.B. auch per Telefon, E-Mail oder durch Computersysteme erfolgen. In diesem Kapitel betrachten wir die persönliche Kommunikation zwischen Vorgesetzten und Mitarbeitern. Zur persönlichen Kommunikation mit Mitarbeitern zählen sowohl formelle Gespräche mit Mitarbeitern als auch eher informelle Gespräche zwischen Tür und Angel. Die Gespräche können dabei mit einzelnen Mitarbeitern (z.B. jährliches Mitarbeitergespräch) oder mit Gruppen von Mitarbeitern (z.B. regelmäßige Projekt- oder Teambesprechungen) stattfinden.

  8. MIT-CSR XIS Project

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This report outlines the proposers' progress toward MIT's contribution to the X-Ray Imaging Spectrometer (XIS) experiment on the Japanese ASTRO-E mission. The report discusses electrical system design, mechanical system design, and ground support equipment.

  9. MIT research in telerobotics

    NASA Technical Reports Server (NTRS)

    Sheridan, T. B.

    1987-01-01

    Ongoing MIT research in telerobotics (vehicles capable of some autonomous sensing and manipulating, having some remote supervisory control by people) and teleoperation (vehicles for sensing and manipulating which are fully controlled remotely by people) is discussed. The current efforts mix human and artificial intelligence/control. The idea of adjustable impedance at either end of pure master-slave teleoperation, and simultaneous coordinated control of teleoperator/telerobotic systems which have more than six degrees of freedom (e.g., a combined vehicle and arm, each with five or six DOF) are discussed. A new cable-controlled parallel link arm which offers many advantages over conventional arms for space is briefly described. Predictor displays to compensate for time delay in teleoperator loops, the use of state estimation to help human control decisions in space, and ongoing research in supervisory command language are covered. Finally, efforts to build a human flyable real-time dynamic computer-graphic telerobot simulator are described. These projects represent most, but not all, of the telerobotics research in our laboratory, supported by JPL, NASA Ames and NOAA.

  10. Grundlegende Steuerungsverfahren im heterogenen Logistiknetz mit Kanban

    NASA Astrophysics Data System (ADS)

    Dickmann, Eva; Dickmann, Philipp; Lödding, Hermann; Möller, Niklas; Rücker, Thomas; Schneider, Herfried M.; Zäh, Michael F.

    In vielen Unternehmen werden heterogene (verschiedene) Steuerungen in einem abgestimmten Konzept kombiniert. Je nach Anwendungsfall und Rahmenbedingungen werden Kombinationen allgemein bekannter Steuerungen oder Steuerungsvarianten gemischt eingesetzt, um eine optimale Steuerung für unterschiedliche Fälle zu erreichen. Hierbei stehen neben den bekannten und weit verbreiteten Methoden, wie Material Requirements Planning (MRP) oder Kanban, auch weniger bekannte oder neue Methoden zur Auswahl, wie die Produktionssteuerung mit dezentraler, bestandsorientierter Fertigungsregelung (DBF). Kanban ist ein simples und effizientes Steuerungskonzept, das in der klassischen Form für spezifische einfache Anwendungsfälle umsetzbar ist. Hochentwickelte Steuerungsalgorithmen können helfen, komplexe Abläufe optimal abzubilden. Mit einer grundlegenden Vereinfachung der Abläufe kann allerdings in vielen Fällen ein wesentlich stärkerer und umfassender Verbesserungseffekt erzielt werden. Die wesentliche Fragestellung sollte folglich lauten: Warum ist der Ablauf nicht mit einer einfachen Steuerung wie Kanban abzubilden? Um die Vorteile des Konzepts auch in untypischen Bereichen anwenden zu können, sind jedoch verschiedene Varianten oder Kanban-ähnliche Steuerungsmethoden entstanden. Darüber hinaus sind in der Praxis hybride Steuerungen im Einsatz, welche so kombiniert werden, dass die Zusammensetzung anspruchsvolle Eigenschaftsbilder noch exakt abbildet. In der Praxis basieren die Steuerungsentscheidungen nur zu einem kleinen Teil auf den eigentlichen Steuerungsalgorithmen, wie sie uns das MRP-System zur Verfügung stellt. Moderne Steuerungswelten" schließen alle relevanten Informationsquellen in eine heterogene Entscheidungsmatrix mit ein. Letztlich zählt nicht, ob die Entscheidung auf den Informationen aus dem MRP-System oder auf Softfacts basierend getroffen wurde, sondern nur, ob die Entscheidung erfolgreich war.

  11. MIT's interferometer CST testbed

    NASA Technical Reports Server (NTRS)

    Hyde, Tupper; Kim, ED; Anderson, Eric; Blackwood, Gary; Lublin, Leonard

    1990-01-01

    The MIT Space Engineering Research Center (SERC) has developed a controlled structures technology (CST) testbed based on one design for a space-based optical interferometer. The role of the testbed is to provide a versatile platform for experimental investigation and discovery of CST approaches. In particular, it will serve as the focus for experimental verification of CSI methodologies and control strategies at SERC. The testbed program has an emphasis on experimental CST--incorporating a broad suite of actuators and sensors, active struts, system identification, passive damping, active mirror mounts, and precision component characterization. The SERC testbed represents a one-tenth scaled version of an optical interferometer concept based on an inherently rigid tetrahedral configuration with collecting apertures on one face. The testbed consists of six 3.5 meter long truss legs joined at four vertices and is suspended with attachment points at three vertices. Each aluminum leg has a 0.2 m by 0.2 m by 0.25 m triangular cross-section. The structure has a first flexible mode at 31 Hz and has over 50 global modes below 200 Hz. The stiff tetrahedral design differs from similar testbeds (such as the JPL Phase B) in that the structural topology is closed. The tetrahedral design minimizes structural deflections at the vertices (site of optical components for maximum baseline) resulting in reduced stroke requirements for isolation and pointing of optics. Typical total light path length stability goals are on the order of lambda/20, with a wavelength of light, lambda, of roughly 500 nanometers. It is expected that active structural control will be necessary to achieve this goal in the presence of disturbances.

  12. MIT's interferometer CST testbed

    NASA Astrophysics Data System (ADS)

    Hyde, Tupper; Kim, Ed; Anderson, Eric; Blackwood, Gary; Lublin, Leonard

    1990-12-01

    The MIT Space Engineering Research Center (SERC) has developed a controlled structures technology (CST) testbed based on one design for a space-based optical interferometer. The role of the testbed is to provide a versatile platform for experimental investigation and discovery of CST approaches. In particular, it will serve as the focus for experimental verification of CSI methodologies and control strategies at SERC. The testbed program has an emphasis on experimental CST--incorporating a broad suite of actuators and sensors, active struts, system identification, passive damping, active mirror mounts, and precision component characterization. The SERC testbed represents a one-tenth scaled version of an optical interferometer concept based on an inherently rigid tetrahedral configuration with collecting apertures on one face. The testbed consists of six 3.5 meter long truss legs joined at four vertices and is suspended with attachment points at three vertices. Each aluminum leg has a 0.2 m by 0.2 m by 0.25 m triangular cross-section. The structure has a first flexible mode at 31 Hz and has over 50 global modes below 200 Hz. The stiff tetrahedral design differs from similar testbeds (such as the JPL Phase B) in that the structural topology is closed. The tetrahedral design minimizes structural deflections at the vertices (site of optical components for maximum baseline) resulting in reduced stroke requirements for isolation and pointing of optics. Typical total light path length stability goals are on the order of lambda/20, with a wavelength of light, lambda, of roughly 500 nanometers. It is expected that active structural control will be necessary to achieve this goal in the presence of disturbances.

  13. MIT Space Engineering Research Center testbed programs

    NASA Technical Reports Server (NTRS)

    Crawley, Edward F.; Miller, David W.

    1991-01-01

    The Space Engineering Research Center (SERC) at M.I.T., started in July 1988, has completed two and one-half years of research. This Semi-Annual Report presents annotated viewgraph material presented at the January 1991 Steering Committee and Technical Representative Review. The objective of the Space Engineering Research Center is to develop and disseminate a unified technology of controlled structures. There has been continued evolution of the concept of intelligent structures (including in this past year the first successful embedding of a microelectronic component into a structural element).

  14. MIT Space Engineering Research Center

    NASA Technical Reports Server (NTRS)

    Crawley, Edward F.; Miller, David W.

    1990-01-01

    The Space Engineering Research Center (SERC) at MIT, started in Jul. 1988, has completed two years of research. The Center is approaching the operational phase of its first testbed, is midway through the construction of a second testbed, and is in the design phase of a third. We presently have seven participating faculty, four participating staff members, ten graduate students, and numerous undergraduates. This report reviews the testbed programs, individual graduate research, other SERC activities not funded by the Center, interaction with non-MIT organizations, and SERC milestones. Published papers made possible by SERC funding are included at the end of the report.

  15. MIT January Operational Internship Experience

    NASA Technical Reports Server (NTRS)

    Bosanac, Natasha; DeVivero, Charlie; James, Jillian; Perez-Martinez, Carla; Pino, Wendy; Wang, Andrew; Willett, Ezekiel; Williams, Kwami

    2010-01-01

    This viewgraph presentation describes the MIT January Operational Internship Experience (JOIE) program. The topics include: 1) Landing and Recovery; 2) Transportation; 3) Shuttle Processing; 4) Constellation Processing; 5) External Tank; 6) Launch Pad; 7) Ground Operations; 8) Hypergolic Propellants; 9) Environmental; 10) Logistics; 11) Six Sigma; 12) Systems Engineering; and 13) Human Factors.

  16. Teaching ``The Physics of Energy'' at MIT

    NASA Astrophysics Data System (ADS)

    Jaffe, Robert

    2009-05-01

    New physics courses on energy are popping up at colleges and universities across the country. Many require little or no previous physics background, aiming to introduce a broad audience to this complex and critical problem, often augmenting the scientific message with economic and policy discussions. Others are advanced courses, focussing on highly specialized subjects like solar voltaics, nuclear physics, or thermal fluids, for example. About two years ago Washington Taylor and I undertook to develop a course on the ``Physics of Energy'' open to all MIT students who had taken MIT's common core of university level calculus, physics, and chemistry. By avoiding higher level prerequisites, we aimed to attract and make the subject relevant to students in the life sciences, economics, etc. --- as well as physical scientists and engineers --- who want to approach energy issues in a sophisticated and analytical fashion, exploiting their background in calculus, mechanics, and E & M, but without having to take advanced courses in thermodynamics, quantum mechanics, or nuclear physics beforehand. Our object was to interweave teaching the fundamental physics principles at the foundations of energy science with the applications of those principles to energy systems. We envisioned a course that would present the basics of statistical, quantum, and fluid mechanics at a fairly sophisticated level and apply those concepts to the study of energy sources, conversion, transport, losses, storage, conservation, and end use. In the end we developed almost all of the material for the course from scratch. The course debuted this past fall. I will describe what we learned and what general lessons our experience might have for others who contemplate teaching energy physics broadly to a technically sophisticated audience.

  17. Unfälle mit Pkw

    NASA Astrophysics Data System (ADS)

    Burg, Heinz

    Der Verkehrsunfall ereignete sich innerorts auf einer Kreuzung mit rechts vor links Regelung. Es galt dort die allgemeine Geschwindigkeitsbegrenzung auf 50 km/h. Zur Unfallzeit war es hell und trocken. Die Fahrbahn hatte eine Schwarzdecke.

  18. Workstation-assisted education at MIT

    NASA Astrophysics Data System (ADS)

    Champine, George A.

    1992-06-01

    MIT launched a major new initiative called Project Athena in 1983 to improve the quality of education through the introduction of a high-quality computing infrastructure throughout the campus. Implementation of the Project Athena computing environment required eight years, cost about 100 million, and was sponsored by Digital Equipment and IBM in addition to MIT. The Athena computing environment is based almost entirely on workstations from these two vendors using the Unix operating system. Project Athena is now complete. The resulting computer system has been turned over to the campus computing organization for ongoing operation and maintenance. The computing environment available at MIT for education has been significantly improved. Students are graduating today that have never known life at MIT without the ubiquitous availability of high-quality computing. This article provides an overview of the initial objectives and strategies of Project Athena at MIT relative to its educational use. The specific strategies that MIT employed in the use of work-stations in educational are then described. These strategies are contrasted with other available strategies. Specific examples of the use of workstations are presented. An important element in current and future education delivery is multimedia. Athena in conjunction with the MIT Media Lab has one of the largest efforts in multimedia development of any of the universities, and MIT is using multimedia in education on a daily basis. A new laboratory, the Center for Educational Computing Initiatives, has been established with a major focus on multimedia. Finally the lessons learned from Athena relative to its primary objective — that of improving education — are reviewed.

  19. Photovoltaik Hybrid-Solarzellen mit Nanopartikeln

    NASA Astrophysics Data System (ADS)

    Leute, Angelika

    2004-09-01

    Die organische Photovoltaik auf der Basis halbleitender Polymere bietet eine kostengünstige Alternative zu Solarzellen aus Silizium. Allerdings weisen die organischen Materialien relativ schlechte Ladungstransporteigenschaften auf. Hybrid-Solarzellen, in denen Polymere mit geeigneten anorganischen Halbleitern kombiniert sind, besitzen einerseits die praktischen Vorteile der Organik und andererseits die hohe Elektronenbeweglichkeit der anorganischen Materialien. Wissenschaftler der Technischen Universität Eindhoven haben kürzlich Hybrid-Solarzellen vorgestellt, die aus einem halbleitenden Polymer mit Zinkoxid-Nanopartikeln bestehen.

  20. MIT Lincoln Laboratory: Physics and Technology in the National Interest

    NASA Astrophysics Data System (ADS)

    Ralston, Richard

    2001-03-01

    This year, MIT is celebrating the 50th anniversary of the founding of Lincoln Laboratory, which was formed at the request of the DoD with the initial goal of developing a national air defense system. In its 50 years, the Laboratory staff have made significant contributions in diverse areas including radar imaging, satellite communications, digital signal processing, computer science, semiconductor materials and solid state physics. The Laboratory has been true to its mission statement, which places strong emphasis on the application of advanced electronics to R&D in the national interest. Much of the technology is transitioned to U.S. industry for both government and commercial use. Annually more than 500 publications and meeting speeches are given, and cooperative developments with industry have targeted technology transitions ranging from next-generation photolithographic tools to microchip lasers. The Laboratory staff have been granted over 400 patents, and license to this intellectual property is at the core of many of the over 70 spin-off companies. MIT employs 2,300 people at Lincoln, including 1,200 professionals with degrees in physics, math, computer science, materials science and the engineering disciplines. Two-fifths of the professional staff are at the doctoral level; over two-thirds hold advanced degrees. This presentation will describe recent examples of research challenges for physicists in a multidisciplinary project-oriented environment.

  1. Wrestling with Pedagogical Change: The TEAL Initiative at MIT

    ERIC Educational Resources Information Center

    Breslow, Lori

    2010-01-01

    In the late 1990s, the physics department at the Massachusetts Institute of Technology (MIT) had a problem. The department was responsible for teaching the two required physics courses that are part of the General Institute Requirements (GIRs), MIT's core curriculum--Physics I (mechanics, or in MIT parlance, 8.01) and Physics II (electricity and…

  2. Abdichtungen im Verbund mit Fliesen und Platten

    NASA Astrophysics Data System (ADS)

    Platts, Thomas

    Abdichtungen im Verbund mit Fliesen und Platten, im Folgenden auch als Verbundabdichtungen oder mit Kurzzeichen als AIV bezeichnet, haben sich in der Baupraxis insbesondere in Innenräumen wegen des vereinfachten konstruktiven Aufbaus gegenüber Bahnenabdichtungen nach DIN 18195-5 [14.1] in der Mehrzahl der Ausführungen durchgesetzt und bewährt. Sie können im Innen- und Außenbereich angeordnet werden und sind dadurch gekennzeichnet, dass die Nutzschicht in Boden- und Wandbereichen im Dünnbettverfahren unmittelbar auf die Abdichtung aufgebracht wird. Aufwändige Zwischenschichten oder Einbauteile wie armierter Putz, Telleranker etc. entfallen (Bild 14.1) und es lassen sich geringere Aufbauhöhen realisieren.

  3. Flight research with the MIT Daedalus prototype

    NASA Technical Reports Server (NTRS)

    Bussolari, Steven R.; Youngren, Harold H.; Langford, John S.

    1987-01-01

    The MIT Light Eagle human-powered aircraft underwent long-duration testing over Rogers Dry Lake in California during January, 1987. Designed as a prototype for the MIT Daedalus Project, the Light Eagle's forty-eight flights provided pilot training, established new distance records for human-powered flight, and provided quantitative data through a series of instrumented flight experiments. The experiments focused on: (1) evaluating physiological loads on the pilot, (2) determining airframe power requirements, and (3) developing an electronic flight control system. This paper discusses the flight test program, its results and their implications for the follow-on Daedalus aircraft, and the potential uses of the Light Eagle as a low Reynolds number testbed.

  4. Mishap Investigation Team (MIT) - Barksdale AFB, Louisiana

    NASA Technical Reports Server (NTRS)

    Stepaniak, Philip

    2005-01-01

    The Shuttle Program is organized to support a Shuttle mishap using the resources of the MIT. The afternoon of Feb. 1, 2003, the MIT deployed to Barksdale AFB. This location became the investigative center and interim storage location for crewmembers received from the Lufkin Disaster Field Office (DFO). Working under the leadership of the MIT Lead, the medical team executed a short-term plan that included search, recovery, and identification including coordination with the Armed Forces Institute of Pathology Temporary operations was set up at Barksdale Air Force Base for two weeks. During this time, coordination with the DFO field recovery teams, AFIP personnel, and the crew surgeons was on going. In addition, the crewmember families and NASA management were updated daily. The medical team also dealt with public reports and questions concerning biological and chemical hazards, which were coordinated with SPACEHAB, Inc., Kennedy Space Center (KSC) Medical Operations and the Johnson Space Center (JSC) Space Medicine office. After operations at Barksdale were concluded the medical team transitioned back to Houston and a long-term search, recovery and identification plan was developed.

  5. The MIT Program, Competition, and Ethics

    NASA Astrophysics Data System (ADS)

    Bradt, Hale V.

    2013-01-01

    The MIT program in x-ray astronomy was, and still is, diverse and productive. Bruno Rossi and later George Clark, as the nominal leaders of the “x-ray astronomy group” created a “hands-off” culture wherein individual researchers could develop their own independent programs. Walter Lewin, Claude Canizares, and I as well as those in the next academic generations, e.g., Saul Rappaport and George Ricker, were able to thrive in this environment. MIT researchers were principal investigators or providers of x-ray instruments on sounding rockets and balloons in the 1960s and then in later years on nine satellite missions, OSO-7, SAS-3, HEAO-1, Einstein, ASCA, RXTE, Chandra, HETE-2, and Suzaku. Such a diverse program involved collaborations with other institutions and of course striving for primacy in discovery and competition for NASA resources. Looking back, I see a high degree of ethical behavior among the observational x-ray community during those years. In competition, we remembered that we might well be collaborating the following year and behaved accordingly. Many of us in the x-ray community had been friends since graduate school days and did not want to lose those relationships. Am I viewing the past through rose colored glasses? I think not. A vignette on this topic: In 1967, I was debating vigorously with Herb Gursky of AS&E about which institution, MIT or AS&E, should be the lead on the fourth paper (Oda et al. 1967, ApJ 148, L5) based on data from the 1966 AS&E rocket flight which had led to Allan Sandage’s (and Japanese) identification of Sco X-1 (Sandage, et al. 1966, ApJ. 146, 316). I and my Italian colleague, Gianfranco Spada, and our Japanese colleague, Minoru Oda, both then visiting MIT, had actively supported that flight. After one rather heated discussion with Herb about this, - I was the heated one; he always remained calm - he left my office saying: “Hale, however this comes out, let’s remain friends.” I treasured that comment and

  6. Erlebniseinkauf in der Innenstadt mit hoher Akzeptanz

    NASA Astrophysics Data System (ADS)

    Pangels, Rolf

    2002-03-01

    Im Oktober 2000 führte die BAG zum zehnten Mal die über die Grenzen des Einzelhandels bekannte Untersuchung "Kundenverkehr" in mehr als hundertfünfzig deutschen Städten durch. In Kooperation mit der Swiss Retail Federation sowie mit Unterstützung der femged (European Federation of Medium-size and Major Retailers) wurde die Untersuchung erstmals auch in der Schweiz und in Österreich durchgeführt. Es beteiligten sich insgesamt 463 Unternehmen an der Untersuchung, die knapp 9,5 Mio. Besucher gezählt haben und davon mehr als 360.000 Kunden nach bestimmten Parametern befragten. Die Daten für Deutschland wurden, wie in den Jahren zuvor, vom Institut für Handelsforschung an der Universität Köln ausgewertet. Die Zahlen der Untersuchung in der Schweiz und Österreich wurden von der wirtschafts- und sozialwissenschaftlichen Beratungsgesellschaft ECON-Consult in Köln zusammengetragen und analysiert.

  7. MMPI and MIT Discriminators of Biogenic and Psychogenic Impotence

    ERIC Educational Resources Information Center

    Beutler, Larry E.; And Others

    1975-01-01

    Male patients complaining of impotence (N=32) were administered the Male Impotence Test (MIT) and the Minnesota Multiphasic Personality Inventory (MMPI). The results suggested that the MIT is without value for differentiating between psychogenic and biogenic impotence, whereas two rules from the MMPI appropriately classified 90 percent of the…

  8. Physik gestern und heute: Visualisierung mit der Schlierenmethode

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2006-07-01

    Der Name des österreichischen Forschers Ernst Mach ist heute noch mit der Schallgeschwindigkeit verbunden. Diese Auszeichnung resultiert aus Machs Untersuchungen, wie sich Projektile mit Überschallgeschwindigkeit durch die Luft bewegen. Gerade in jüngster Zeit hat die Anwendung derartiger Methoden durch technische Modifikationen wieder einen Aufschwung erfahren.

  9. Unfälle mit Kleintransportern

    NASA Astrophysics Data System (ADS)

    Tschirschwitz, Christian

    Auf einer außerörtlichen Bundesstraße geriet ein mit vier Personen besetzter Pkw Toyota Corolla aus letztlich nicht vollständig geklärten Gründen ins Schleudern. Nachdem sich das Fahrzeug beträchtlich entgegen dem Uhrzeigersinn ausgedreht hatte, prallte ein entgegenkommender Kleintransporter VW T4 frontal an die rechte Flanke des Toyota. Der Transporter wurde gedreht, ausgehoben und durch einen Pkw Ford Escort unterfahren. Alle Fahrzeuge kamen in Kollisionsortnähe zum Endstand. Die vier Toyota-Insassen wurden getötet. Aus den anderen Fahrzeugen wurden sechs Personen überwiegend schwer verletzt. Unbeteiligte Zeugen waren nicht vorhanden.

  10. Final Technical Report for the MIT Annular Fuel Research Project

    SciTech Connect

    Mujid S. Kazimi; Pavel Hejzlar

    2008-01-31

    MIT-NFC-PR-082 (January 2006) Abstract This summary provides an overview of the results of the U.S. DOE funded NERI (Nuclear Research ENergy Initiative) program on development of the internally and externally cooled annular fuel for high power density PWRs. This new fuel was proposed by MIT to allow a substantial increase in poer density (on the order of 30% or higher) while maintaining or improving safety margins. A comprehensive study was performed by a team consisting of MIT (lead organization), Westinghuse Electric Corporation, Gamma Engineering Corporation, Framatome ANP(formerly Duke Engineering) and Atomic Energy of Canada Limited.

  11. MIT ASTROMAG 1.7 meter disk magnet design report

    NASA Technical Reports Server (NTRS)

    Marston, P. G.; Hale, J. R.; Vieira, R.; Zhukovsky, A.; Titus, P. H.; Sullivan, J. D.; Dawson, A. M.

    1990-01-01

    MIT has proposed a magnet design for ASTROMAG, which has demonstrated substantial improvement in performance as compared with the present HEAO baseline design. Several advantages of the MIT disk design are listed along with design characteristics. Details of field contours and active field regions are shown along with comparisons with other designs. Three alternative design configurations for the ASTROMAG disk coils are summarized. The parameters of the conductors are listed and basic parameters for each of the complete systems are shown.

  12. Education Outreach at MIT Plasma Science and Fusion Center

    NASA Astrophysics Data System (ADS)

    Censabella, V.; Rivenberg, P.

    1999-11-01

    Outreach at the MIT PSFC consists of volunteers working together to increase the public's knowledge of fusion and plasma-related experiments. Seeking to generate excitement about science, engineering and mathematics, the PSFC holds a number of outreach activities throughout the year, such as Middle and High School Outreach Days. Outreach also includes the Mr. Magnet Program, which uses an interactive strategy to engage elementary school children. The PSFC maintains a Home Page on the World Widee Web, which can be reached at http://psfc.mit.edu.

  13. MIT Mints a Valuable New Form of Academic Currency

    ERIC Educational Resources Information Center

    Carey, Kevin

    2012-01-01

    The Massachusetts Institute of Technology (MIT) has invented or improved many world-changing things--radar, information theory, and synthetic self-replicating molecules, to name a few. Last month the university announced, to mild fanfare, an invention that could be similarly transformative, this time for higher education itself. It is called MITx.…

  14. The Harvard-MIT PHD Program in Bioastronautics

    NASA Astrophysics Data System (ADS)

    Young, Laurence R.; Natapoff, Alan

    2008-06-01

    The National Space Biomedical Research Institute (NSBRI)1 supports a PhD program in Space Life Sciences with a specialty in Bioastronautics at MIT. (A sibling program operates at TAMU.) It gives broad training in life sciences, emphasizes hands-on field experience, provides access to laboratories in the Harvard-MIT community for thesis research, and prepares students for many options in space biomedicine. The Program trains prospective leaders in the field able to manage the challenges of design for the life-hostile space environment. Beyond subject and thesis work, students participate in a summer internship and a clinical preceptorship at a NASA center--and an introduction to clinical medicine and medical engineering.

  15. The Kubo-Greenwood expression and 2d MIT transport

    NASA Astrophysics Data System (ADS)

    Castner, Theodore

    2010-03-01

    The 2d MIT in GaAs heterostructures (p- and n-type)features a mobility that drops continuously as the reduced density x= n/nc-1 is decreased. The Kubo-Greenwood result [1] predicts μ = (eɛh/hnc)α^2(x) where α is a normalized DOS. α(x)is obtained from the data [p-type, Gao et al. [2]; n-type Lilly et al. [3

  16. Materials

    NASA Technical Reports Server (NTRS)

    Glaessgen, Edward H.; Schoeppner, Gregory A.

    2006-01-01

    NASA Langley Research Center has successfully developed an electron beam freeform fabrication (EBF3) process, a rapid metal deposition process that works efficiently with a variety of weldable alloys. The EBF3 process can be used to build a complex, unitized part in a layer-additive fashion, although the more immediate payoff is for use as a manufacturing process for adding details to components fabricated from simplified castings and forgings or plate products. The EBF3 process produces structural metallic parts with strengths comparable to that of wrought product forms and has been demonstrated on aluminum, titanium, and nickel-based alloys to date. The EBF3 process introduces metal wire feedstock into a molten pool that is created and sustained using a focused electron beam in a vacuum environment. Operation in a vacuum ensures a clean process environment and eliminates the need for a consumable shield gas. Advanced metal manufacturing methods such as EBF3 are being explored for fabrication and repair of aerospace structures, offering potential for improvements in cost, weight, and performance to enhance mission success for aircraft, launch vehicles, and spacecraft. Near-term applications of the EBF3 process are most likely to be implemented for cost reduction and lead time reduction through addition of details onto simplified preforms (casting or forging). This is particularly attractive for components with protruding details that would require a significantly large volume of material to be machined away from an oversized forging, offering significant reductions to the buy-to-fly ratio. Future far-term applications promise improved structural efficiency through reduced weight and improved performance by exploiting the layer-additive nature of the EBF3 process to fabricate tailored unitized structures with functionally graded microstructures and compositions.

  17. Comments on the MIT Assessment of the Mars One Plan

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.

    2015-01-01

    The MIT assessment of the Mars One mission plan reveals design assumptions that would cause significant difficulties. Growing crops in the crew chamber produces excessive oxygen levels. The assumed in-situ resource utilization (ISRU) equipment has too low a Technology Readiness Level (TRL). The required spare parts cause a large and increasing launch mass logistics burden. The assumed International Space Station (ISS) Environmental Control and Life Support (ECLS) technologies were developed for microgravity and therefore are not suitable for Mars gravity. Growing food requires more mass than sending food from Earth. The large number of spares is due to the relatively low reliability of ECLS and the low TRL of ISRU. The Mars One habitat design is similar to past concepts but does not incorporate current knowledge. The MIT architecture analysis tool for long-term settlements on the Martian surface includes an ECLS system simulation, an ISRU sizing model, and an analysis of required spares. The MIT tool showed the need for separate crop and crew chambers, the large spare parts logistics, that crops require more mass than Earth food, and that more spares are needed if reliability is lower. That ISRU has low TRL and ISS ECLS was designed for microgravity are well known. Interestingly, the results produced by the architecture analysis tool - separate crop chamber, large spares mass, large crop chamber mass, and low reliability requiring more spares - were also well known. A common approach to ECLS architecture analysis is to build a complex model that is intended to be all-inclusive and is hoped will help solve all design problems. Such models can struggle to replicate obvious and well-known results and are often unable to answer unanticipated new questions. A better approach would be to survey the literature for background knowledge and then directly analyze the important problems.

  18. Real-time control of the MIT vehicle emulation system

    NASA Technical Reports Server (NTRS)

    Durfee, William K.; Idris, Husni R.; Dubowsky, Steven

    1991-01-01

    The MIT vehicle emulation system (VES) is an experimental facility designed to facilitate the study of controlling robots fixed to nonstationary bases. This includes assembly and repair manipulators attached to space vehicles, or to the space shuttle arm, as well as manipulators fixed to the bed of moving ground vehicles. Controlling manipulators under these conditions for endpoint force and positioning tasks requires both the development of new theory, and the development of a testbed for verifying theoretical results through experimentation. A description is presented of the technical details of the real-time controller for the second generation VES system.

  19. Research in Boron Neutron Capture Therapy at MIT LABA

    SciTech Connect

    Yanch, J.C.; Shefer, R.E.; Klinkowstein, R.E.; Howard, W.B.; Song, H.; Blackburn, B.; Binello, E.

    1997-02-01

    A 4.1 MeV tandem electrostatic accelerator designed for research into Boron Neutron Capture Therapy (BNCT) has recently been installed in the MIT Laboratory for Accelerator Beam Applications (LABA). This accelerator uses a very high current switch mode high voltage power supply in conjunction with a multi-cusp negative ion source to supply the multimilliampere current required for clinical BNCT applications. A number of individual research projects aimed at evaluating the potential of this accelerator design as a hospital-based neutron source for radiation therapy of both tumors and rheumatoid arthritis are described here. {copyright} {ital 1997 American Institute of Physics.}

  20. Mit Mathematik zu Mehr Intelligenz in der Logistik

    NASA Astrophysics Data System (ADS)

    Möhring, Rolf H.; Schenk, Michael

    Die Lösung logistischer Probleme ist ein wichtiger Aspekt menschlichen Handelns seit Menschen gemeinsam zielgerichtet tätig wurden. Die Grundlagen dessen, was wir heute Logistik nennen, entstammen dem militärischen Bereich. So basierte z. B. das römische Imperium in starkem Maße auf militärisch-logistischen Glanzleistungen. Ob damals bereits mathematische Überlegungen eine Rolle spielten, wissen wir heute nicht. Jedoch versuchte z. B. Napoleon, der mit den bedeutendsten Mathematikern seiner Zeit befreundet war, den Transport seiner Truppen und die Verbreitung von Informationen zu optimieren und strategisch einzusetzen.1,2

  1. Brennraumdruckregelung von Dieselmotoren mit homogener Kompressionszündung (HCCI)

    NASA Astrophysics Data System (ADS)

    Kohlhase, Martin

    In den letzten Jahren ist die Zahl der neu zugelassenen Dieselfahrzeuge stark gestiegen. Diese Entwicklung ist zum einen darauf zurückzuführen, dass der Dieselmotor im Vergleich zum Ottomotor einen besseren thermischen Wirkungsgrad aufweist. Einhergehend damit ist der Kraftstoffverbrauch und somit der CO2-Ausstoß im Gegensatz zum Ottomotor deutlich geringer. Zum anderen hat der Dieselmotor im Bereich Fahrspaß und -komfort durch Einzug der Direkteinspritzung basierend auf Common-Rail-Systemen und durch effiziente Abgasturbolader mit variabler Turbinengeometrie (VTG) deutlich an Akzeptanz gewonnen.

  2. Characteristics of the MIT microwiggler for free electron laser applications

    SciTech Connect

    Catravas, P.; Stoner, R.; Bekefi, G.

    1995-12-31

    We report work on the development of microwiggler technology for free electron laser research. The MIT microwiggler is a pulsed electromagnet with 70 periods of 8.8 mm each which generates a peak on-axis field of 4.2 kG. The wiggler is characterized by extensive tunability. We developed a novel tuning regimen to control 140 degrees of freedom afforded by the individually tunable half periods and achieved an rms spread in the peak amplitudes of 0.08%. This is the lowest attained to date in any sub-cm period wiggler. The microwiggler design and comprehensive measurements of its characteristics will be described.

  3. MIT nuclear reactor laboratory high school teaching program

    SciTech Connect

    Olmez, I. )

    1991-11-01

    For the last 6 years, the Massachusetts Institute of Technology (MIT) Nuclear Reactor Laboratory's academic and scientific staff{sup a} have been conducting evening seminars for precollege science teachers, parents, and high school students from the New England area. These seminars, as outlined in this paper, are intended to give general information on nuclear technologies with specific emphasis on radiation physics, nuclear medicine, nuclear chemistry, and ongoing research activities at the MIT research reactor. The ultimate goal is to create interest or build on the already existing interest in science and technology by, for example, special student projects. Several small projects have already been completed ranging from environmental research to biological reactions with direct student involvement. Another outcome of these seminars was the change in attitudes of science teachers toward nuclear technology. Numerous letters have been received from the teachers and parents stating their previous lack of knowledge on the beneficial aspects of nuclear technologies and the subsequent inclusion of programs in their curriculum for educating students so that they may also develop a more positive attitude toward nuclear power.

  4. Education Outreach at MIT Plasma Science Fusion Center

    NASA Astrophysics Data System (ADS)

    Censabella, V.; Nachtrieb, R.; Rivenberg, P.

    1998-11-01

    Outreach at the MIT PSFC consists of volunteers working together to increase the public's knowledge of fusion and plasma-related experiments. Seeking to generate excitement about science, engineering and mathematics, the PSFC holds a number of outreach activities throughout the year, such as Middle and High School Outreach Days. Outreach also includes the Mr. Magnet Program, which uses an interactive strategy to engage elementary school children. Included in this year's presentation will be a live demo of a compressed-air bottle rocket (really a one-liter plastic soda bottle) for use in high school science classrooms that researchers at the Cambridge Physics Outlet (a PSFC spin-off company) have developed. To prepare the rocket for launch, the bottle is filled with compressed air at pressures up to 80 psi and the end is plugged. The rocket is released when the plug is pulled. The gas escapes at supersonic velocities and accelerates the bottle at over 1000 m/s^2. The velocity of the bottle is measured at many locations along its ``trajectory". A simple thermodynamic model predicts performance in excellent agreement with observation. The PSFC maintains a Home Page on the World Wide Web, which can be reached at http://pfc.mit.edu.

  5. M.I.T. and the Federal Government. An Examination of the Effects of Government Regulation and Research Support on Selected Parts of M.I.T.

    ERIC Educational Resources Information Center

    Garvin, David

    A self-study was undertaken at the Massachusetts Institute of Technology (M.I.T.) to examine the impact of the federal government on it. M.I.T. is a large institution with an enrollment of 8,000, a faculty of 950, and a total teaching staff of 1,700. Of its operating expenses by far the largest source of funds in recent years has been sponsored…

  6. Mobile-IT Education (MIT.EDU): M-Learning Applications for Classroom Settings

    ERIC Educational Resources Information Center

    Sung, M.; Gips, J.; Eagle, N.; Madan, A.; Caneel, R.; DeVaul, R.; Bonsen, J.; Pentland, A.

    2005-01-01

    In this paper, we describe the Mobile-IT Education (MIT.EDU) system, which demonstrates the potential of using a distributed mobile device architecture for rapid prototyping of wireless mobile multi-user applications for use in classroom settings. MIT.EDU is a stable, accessible system that combines inexpensive, commodity hardware, a flexible…

  7. Assessing International Product Design and Development Graduate Courses: The MIT-Portugal Program

    ERIC Educational Resources Information Center

    Dori, Yehudit Judy; Silva, Arlindo

    2010-01-01

    The Product Design and Development (PDD) course is part of the graduate curriculum in the Engineering Design and Advanced Manufacturing (EDAM) study in the MIT-Portugal Program. The research participants included about 110 students from MIT, EDAM, and two universities in Portugal, Instituto Superior Técnico-Universidade Técnica de Lisboa (IST) and…

  8. Scratch that: MIT's Mitchel Resnick Says Kids Should Do It for Themselves

    ERIC Educational Resources Information Center

    Traylor, Scott

    2008-01-01

    Mitchel Resnick is a researcher, inventor, and professor at MIT's Media Laboratory in Cambridge, MA, and the founder of the Lifelong Kindergarten Group at MIT. He is the lead innovator behind many cutting-edge learning technologies and projects for children, including the Computer Clubhouse, PicoCrickets, and the wildly successful consumer…

  9. Temperature-driven and photo-induced MIT behaviors of VO2 nanowires

    NASA Astrophysics Data System (ADS)

    Sohn, Ahrum; Kim, Dong-Wook; Byun, Ji-Won; Baik, Jeong Min

    2014-03-01

    VO2 shows a metal-insulator transition (MIT) and structural phase transition (SPT) at critical temperature (Tc) of 343K. It has been known that the MIT and SPT behaviors of VO2 can be tuned by external stimuli such as light, electric-field, and strain. We carried out comparative studies of MIT behaviors of VO2 nanowires during heating-cooling cycles with and without illumination using several light sources (red, blue, and UV). Light can induce change in Tc and hysteresis width of the resistance change. We have investigated influences of light on SPT during MIT. In this presentation, we will discuss possible physical origins for the photo-induced effects on the MIT behaviors of the VO2 nanowires.

  10. Child Care is Everybody's Baby: A Comprehensive Report of Child Care Services, Past, Present, and Future at M.I.T. Final Child Care Proposals as Accepted by M.I.T.

    ERIC Educational Resources Information Center

    Swartz, Marilyn S.

    The report on child care services at M.I.T. explores the following areas: (1) Planning Issues: Why Should M.I.T. Be Involved in Child Care?--educational concerns, services, benefits and costs, priorities, resource allocation; (2) Background for Planning; Current Institute Child Care Programs--a concise history, M.I.T. summer day camp, the…

  11. MIT-KSC space life sciences telescience testbed

    NASA Technical Reports Server (NTRS)

    1989-01-01

    A Telescience Life Sciences Testbed is being developed. The first phase of this effort consisted of defining the experiments to be performed, investigating the various possible means of communication between KSC and MIT, and developing software and hardware support. The experiments chosen were two vestibular sled experiments: a study of ocular torsion produced by Y axis linear acceleration, based on the Spacelab D-1 072 Vestibular Experiment performed pre- and post-flight at KSC; and an optokinetic nystagmus (OKN)/linear acceleration interaction experiment. These two experiments were meant to simulate actual experiments that might be performed on the Space Station and to be representative of space life sciences experiments in general in their use of crew time and communications resources.

  12. Energy Flow in the Magnetosphere-Ionosphere-Thermosphere (MIT) System

    NASA Astrophysics Data System (ADS)

    Huang, C. Y.; Huang, Y.; Su, Y. J.; Sutton, E. K.; Hairston, M. R.

    2015-12-01

    The conventional model of energy input and dissipation in the IT system assumes that the auroral zone is the primary locus for these processes. Recent work has revealed that, contrary to this traditional view, the polar cap can play a significant role in energy transfer during magnetic storms. DMSP measurements of DC Poynting flux shows high levels of electromagnetic energy entering the polar cap at all local times (LTs) in both hemispheres during storms. An analysis of ion temperature observations at DMSP altitudes shows that the largest temperature increases occur at polar latitudes during magnetic activity. Finally, observations of neutral densities from the CHAMP, GRACE and GOCE spacecraft show that the highest frequency of occurrence of heated neutrals occurs close to the poles in both hemispheres. These results demand a revision of the standard paradigm for MIT coupling.

  13. [R]MIT Research Centre at Delft University of Technology: A Bridge between Research, Education, Society and Profession

    ERIC Educational Resources Information Center

    Zijlstra, Hielkje

    2009-01-01

    In 2006, we launched the [R]MIT Research Centre (Modification, Intervention Transformation) at the Faculty of Architecture at Delft University of Technology. [R]MIT was founded to respond to the need for an integrated, multi-disciplinary approach to the transformation of the built environment. [R]MIT aims to bring momentum to the renewal of…

  14. 2mit, an Intronic Gene of Drosophila melanogaster timeless2, Is Involved in Behavioral Plasticity

    PubMed Central

    Benna, Clara; Leonardi, Emanuela; Romoli, Ottavia; Cognolato, Moira; Tosatto, Silvio C. E.; Costa, Rodolfo; Sandrelli, Federica

    2013-01-01

    Background Intronic genes represent ~6% of the total gene complement in Drosophila melanogaster and ~85% of them encode for proteins. We recently characterized the D. melanogaster timeless2 (tim2) gene, showing its active involvement in chromosomal stability and light synchronization of the adult circadian clock. The protein coding gene named 2mit maps on the 11th tim2 intron in the opposite transcriptional orientation. Methodology/Principal Findings Here we report the molecular and functional characterization of 2mit. The 2mit gene is expressed throughout Drosophila development, localizing mainly in the nervous system during embryogenesis and mostly in the mushroom bodies and ellipsoid body of the central complex in the adult brain. In silico analyses revealed that 2mit encodes a putative leucine-Rich Repeat transmembrane receptor with intrinsically disordered regions, harboring several fully conserved functional interaction motifs in the cytosolic side. Using insertional mutations, tissue-specific over-expression, and down-regulation approaches, it was found that 2mit is implicated in adult short-term memory, assessed by a courtship conditioning assay. In D. melanogaster, tim2 and 2mit do not seem to be functionally related. Bioinformatic analyses identified 2MIT orthologs in 21 Drosophilidae, 4 Lepidoptera and in Apis mellifera. In addition, the tim2-2mit host-nested gene organization was shown to be present in A. mellifera and maintained among Drosophila species. Within the Drosophilidae 2mit-hosting tim2 intron, in silico approaches detected a neuronal specific transcriptional binding site which might have contributed to preserve the specific host-nested gene association across Drosophila species. Conclusions/Significance Taken together, these results indicate that 2mit, a gene mainly expressed in the nervous system, has a role in the behavioral plasticity of the adult Drosophila. The presence of a putative 2mit regulatory enhancer within the 2mit-hosting tim2

  15. Hover Testing of the NASA/Army/MIT Active Twist Rotor Prototype Blade

    NASA Technical Reports Server (NTRS)

    Wilbur, Matthew L.; Yeager, William T., Jr.; Wilkie, W. Keats; Cesnik, Carlos E. S.; Shin, Sangloon

    2000-01-01

    Helicopter rotor individual blade control promises to provide a mechanism for increased rotor performance and reduced rotorcraft vibrations and noise. Active material methods, such as piezoelectrically actuated trailing-edge flaps and strain-induced rotor blade twisting, provide a means of accomplishing individual blade control without the need for hydraulic power in the rotating system. Recent studies have indicated that controlled strain induced blade twisting can be attained using piezoelectric active fiber composite technology. In order to validate these findings experimentally, a cooperative effort between NASA Langley Research Center, the Army Research Laboratory, and the MIT Active Materials and Structures Laboratory has been developed. As a result of this collaboration an aeroelastically-scaled active-twist model rotor blade has been designed and fabricated for testing in the heavy gas environment of the Langley Transonic Dynamics Tunnel (TDT). The results of hover tests of the active-twist prototype blade are presented in this paper. Comparisons with applicable analytical predictions of active-twist frequency response in hovering flight are also presented.

  16. Star in Deep Freeze Chills Theory, MIT Researchers Report

    NASA Astrophysics Data System (ADS)

    2001-09-01

    CAMBRIDGE, Mass. -- Like a frozen turkey that just won't thaw, a strange star near the center of the Milky Way is surprising MIT experts and colleagues with its remarkably low temperature. The odd behavior is chilling current theories of stellar physics. A famously battered neutron star named KS 1731-260 appears no hotter than some of its tranquil brethren, despite enduring the heat of constant thermonuclear explosions with the force of billions of hydrogen bombs every second across a region only a few miles wide for the past 12 years. Dr. Rudi Wijnands, an astrophysicist at MIT's Center for Space Research, used the Chandra X-ray Observatory to measure the temperature of the neutron star at a very opportune moment, only months after the nuclear war apparently ended and the smoke cleared. He presented his team's findings September 5 in Washington, D.C. at a scientific conference entitled "Two Years of Science with Chandra." "Twelve years of constant thermonuclear explosions: One would think that would heat things up," said Wijnands. "This leaves us wondering whether some neutron stars are in the freezer for a much longer time than previously thought and consequently take a long time to heat up, or whether they cool down incredibly fast. Either explanation has profound implications for our field." Neutron stars are the dense, core remains of stars once many times more massive than our Sun. They are created in dazzling supernovas, in which the outer shell of the star explodes into space, and the core, containing about as much mass as the Sun, implodes and collapses into a sphere no wider than Cambridge, Massachusetts. Despite their tiny size, neutron stars are visible in several ways. One is through accretion. Neutron stars are a strong source of gravity. When they exist in binary star systems, such as KS 1731-260, they can attract the gas from what is often a "healthy" hydrogen-burning companion star (although the nature of KS 1731-260's companion is not clear.) Gas

  17. Having Fun with Physics at the MIT Plasma Science and Fusion Center

    NASA Astrophysics Data System (ADS)

    Rivenberg, P.; Thomas, P.; Censabella, V.; Granville, J.; Nachtrieb, R.; Gangadhara, S.

    1997-11-01

    MIT Plasma Science and Fusion Center staff and students are convinced that students learn best not by studying but by doing. This was the impetus behind a group of MIT graduate students who created Cambridge Physics Outlet, a PSFC spin-off company dedicated to creating hands-on experiments. The same impulse fostered the award-winning Mr. Magnet Program, a traveling presentation which uses a hands-on strategy to engage elementary school children. A number of ingenious experiments will be demonstrated. The PSFC maintains a Home Page on the World Wide Web, which can be reached at HTTP://PFC.MIT.EDU.

  18. Vertebrate MitBASE: a specialised database on vertebrate mitochondrial DNA sequences.

    PubMed

    Carone, A; Malladi, S B; Attimonelli, M; Saccone, C

    1999-01-01

    Vertebrate MitBASE is a specialized database where all the vertebrate mitochondrial DNA entries from primary databases are collected, revised and integrated with new information emerging from the literature. Variant sequences are also analyzed, aligned and linked to reference sequences. Data related to the same species and fragment can be viewed over the WWW. The database has a flexible interface and a retrieval system to help non-expert users and contains information not currently available in the primary databases. Vertebrate MitBASE is now available through the MitBASE home page at URL: http://www.ebi.ac.uk/htbin/Mitbase/mitb ase.pl. This work is part of a larger project, MitBASE which is a network of databases covering the full panorama of knowledge on mitochondrial DNA from protists to human sequences.

  19. MIT Study Sees Nuclear Power as Green Weapon Against Global Warming

    NASA Astrophysics Data System (ADS)

    Dawson, Jim

    2003-12-01

    Although the public doesn't yet view nuclear power as a way to mitigate global warming, an MIT study says a global tripling of nuclear power generation could avoid nearly 2 billion tonnes of carbon emissions annually.

  20. Lessons learned from the MIT Tara control and data system

    SciTech Connect

    Gaudreau, M.P.J.; Sullivan, J.D.; Fredian, T.W.; Irby, J.H.; Karcher, C.A.; Rameriz, R.A.; Sevillano, E.; Stillerman, J.A.; Thomas, P.

    1987-10-01

    The control and data system of the MIT Tara Tandem Mirror has worked successfully throughout the lifetime of the experiment (1983 through 1987). As the Tara project winds down, it is appropriate to summarize the lessons learned from the implementation and operation of the control and data system over the years and in its final form. The control system handled approx.2400 I/0 points in real time throughout the 5 to 10 minute shot cycle while the data system, in near real time, handled approx.1000 signals with a total of 5 to 7 Mbytes of data each shot. The implementation depended upon a consistent approach based on separating physics and engineering functions and on detailed functional diagrams with narrowly defined cross communication. This paper is a comprehensive treatment of the principal successes, residual problems, and dilemmas that arose from the beginning until the final hardware and software implementation. Suggestions for future systems of either similar size or of larger scale such as CIT are made in the conclusion. 11 refs., 1 fig.

  1. Educational Outreach at the MIT Plasma Science and Fusion Center

    NASA Astrophysics Data System (ADS)

    Rivenberg, Paul; Thomas, Paul

    2006-10-01

    At the MIT PSFC, student and staff volunteers work together to increase the public's knowledge of fusion science and plasma technology. Seeking to generate excitement in young people about science and engineering, the PSFC hosts a number of educational outreach activities throughout the year, including Middle and High School Outreach Days. The PSFC also has an in-school science demonstration program on the theme of magnetism. The Mr. Magnet Program, headed by Mr. Paul Thomas, has been bringing lively demonstrations on magnetism into local elementary and middle schools for 15 years. This year Mr. Magnet presented the program to nearly 30,000 students at over 67 schools and other events, reaching kindergartners through college freshmen. In addition to his program on magnetism, he is offering an interactive lecture about plasma to high schools. The "Traveling Plasma Lab" encourages students to learn more about plasma science while having fun investigating plasma properties using actual laboratory techniques and equipment. Beyond the classroom, Paul Thomas has provided technical training for Boston Museum of Science staff in preparation for the opening of a Star Wars exhibit. His hands-on demos have also been filmed by the History Channel for a one-hour program about Magnetism, which aired in June 2006.

  2. Echtzeit-Ultraschallsimulation auf Grafik-Prozessoren mit CUDA

    NASA Astrophysics Data System (ADS)

    Reichl, Tobias; Passenger, Josh; Acosta, Oscar; Salvado, Olivier

    Trotz der zunehmenden Verbreitung jüngerer bildgebender Verfahren bleibt medizinischer Ultraschall (US) weiterhin ein wichtiges Hilfsmittel bei chirurgischen Eingriffen und der klinischen Diagnose. Viele US-gestützte medizinische Prozeduren erfordern allerdings ausgiebiges Training, so dass es wünschenswert ist, eine realistische Simulation von US-Bildern zur Verfügung zu stellen. Im Gegensatz zu früheren Ansätzen simulieren wir solche Bilder auf der "Graphics Processing Unit“. Wir erweitern hierzu eine Methode, die von Wein et al. für die Abschätzung von US-Reflexionen aus Daten der Computertomographie (CT) vorgeschlagen wurde, zu einer leichter zu berechnenden Form. Zusätzlich schätzen wir die US-Absorption aus den CT-Daten ab. Mit Hilfe von NVIDIAs "Compute Unified Device Architecture“ (CUDA) simulieren wir Reflexion, Verschattung, Rauschen und radiale Unschärfe, ausgehend von unbearbeiteten CT-Daten in Echtzeit und ohne Vorausberechnung.

  3. Research and Demonstration Program of Day Care Services for M.I.T. Employees. Interim Report.

    ERIC Educational Resources Information Center

    Arterton, Janet Bond

    A survey of day care needs of M.I.T. employees, its resulting information, and a description of the pilot program of day care services undertaken by M.I.T. are included in this report. A survey was administered to all 4,650 Institute employees in April, 1970, and enjoyed a 35% rate of response. The compiled data supports the conclusion that a…

  4. Boer-Mulders function of the pion in the MIT bag model

    NASA Astrophysics Data System (ADS)

    Lu, Zhun; Ma, Bo-Qiang; Zhu, Jiacai

    2012-11-01

    We apply the MIT bag model to study the Boer-Mulders function of the pion, a T-odd function that describes the transverse polarization distribution of the quark inside the pion. We simulate the effect of the gauge link through the “one-gluon-exchange” approximation. We consider both the quark helicity nonflip and double-flip contributions. The result in the MIT bag model is compared with those in the spectator models.

  5. Vibratory Loads Reduction Testing of the NASA/Army/MIT Active Twist Rotor

    NASA Technical Reports Server (NTRS)

    Wilbur, Matthew; Mirick, Paul H.; Yeager, William T., Jr.; Langston, Chester W.; Cesnik, Carlos E. S.; Shin, SangJoon

    2001-01-01

    Recent studies have indicated that controlled strain-induced blade twisting can be attained using piezoelectric active fiber composite technology, and that such advancement may provide a mechanism for reduced rotorcraft vibrations and increased rotor performance. In order to validate these findings experimentally, a cooperative effort between the NASA Langley Research Center, the Army Research Laboratory, and the MIT Active Materials and Structures Laboratory has been developed. As a result of this collaboration a four-bladed, aeroelastically-scaled, active-twist model rotor has been designed and fabricated for testing in the heavy gas test medium of the NASA Langley Transonic Dynamics Tunnel. Initial wind tunnel testing has been conducted to assess the impact of active blade twist on both fixed- and rotating-system vibratory loads in forward flight. The active twist control was found to have a pronounced effect on all system loads and was shown to generally offer reductions in fixed-system loads of 60% to 95%, depending upon flight condition, with 1.1 to 1.4 of dynamic blade twist observed. A summary of the systems developed and the vibratory loads reduction results obtained are presented in this paper.

  6. Benchmarking on Tsunami Currents with ComMIT

    NASA Astrophysics Data System (ADS)

    Sharghi vand, N.; Kanoglu, U.

    2015-12-01

    There were no standards for the validation and verification of tsunami numerical models before 2004 Indian Ocean tsunami. Even, number of numerical models has been used for inundation mapping effort, evaluation of critical structures, etc. without validation and verification. After 2004, NOAA Center for Tsunami Research (NCTR) established standards for the validation and verification of tsunami numerical models (Synolakis et al. 2008 Pure Appl. Geophys. 165, 2197-2228), which will be used evaluation of critical structures such as nuclear power plants against tsunami attack. NCTR presented analytical, experimental and field benchmark problems aimed to estimate maximum runup and accepted widely by the community. Recently, benchmark problems were suggested by the US National Tsunami Hazard Mitigation Program Mapping & Modeling Benchmarking Workshop: Tsunami Currents on February 9-10, 2015 at Portland, Oregon, USA (http://nws.weather.gov/nthmp/index.html). These benchmark problems concentrated toward validation and verification of tsunami numerical models on tsunami currents. Three of the benchmark problems were: current measurement of the Japan 2011 tsunami in Hilo Harbor, Hawaii, USA and in Tauranga Harbor, New Zealand, and single long-period wave propagating onto a small-scale experimental model of the town of Seaside, Oregon, USA. These benchmark problems were implemented in the Community Modeling Interface for Tsunamis (ComMIT) (Titov et al. 2011 Pure Appl. Geophys. 168, 2121-2131), which is a user-friendly interface to the validated and verified Method of Splitting Tsunami (MOST) (Titov and Synolakis 1995 J. Waterw. Port Coastal Ocean Eng. 121, 308-316) model and is developed by NCTR. The modeling results are compared with the required benchmark data, providing good agreements and results are discussed. Acknowledgment: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant

  7. Knocking down mitochondrial iron transporter (MIT) reprograms primary and secondary metabolism in rice plants.

    PubMed

    Vigani, Gianpiero; Bashir, Khurram; Ishimaru, Yasuhiro; Lehmann, Martin; Casiraghi, Fabio Marco; Nakanishi, Hiromi; Seki, Motoaki; Geigenberger, Peter; Zocchi, Graziano; Nishizawa, Naoko K

    2016-03-01

    Iron (Fe) is an essential micronutrient for plant growth and development, and its reduced bioavailability strongly impairs mitochondrial functionality. In this work, the metabolic adjustment in the rice (Oryza sativa) mitochondrial Fe transporter knockdown mutant (mit-2) was analysed. Biochemical characterization of purified mitochondria from rice roots showed alteration in the respiratory chain of mit-2 compared with wild-type (WT) plants. In particular, proteins belonging to the type II alternative NAD(P)H dehydrogenases accumulated strongly in mit-2 plants, indicating that alternative pathways were activated to keep the respiratory chain working. Additionally, large-scale changes in the transcriptome and metabolome were observed in mit-2 rice plants. In particular, a strong alteration (up-/down-regulation) in the expression of genes encoding enzymes of both primary and secondary metabolism was found in mutant plants. This was reflected by changes in the metabolic profiles in both roots and shoots of mit-2 plants. Significant alterations in the levels of amino acids belonging to the aspartic acid-related pathways (aspartic acid, lysine, and threonine in roots, and aspartic acid and ornithine in shoots) were found that are strictly connected to the Krebs cycle. Furthermore, some metabolites (e.g. pyruvic acid, fumaric acid, ornithine, and oligosaccharides of the raffinose family) accumulated only in the shoot of mit-2 plants, indicating possible hypoxic responses. These findings suggest that the induction of local Fe deficiency in the mitochondrial compartment of mit-2 plants differentially affects the transcript as well as the metabolic profiles in root and shoot tissues. PMID:26685186

  8. 76 FR 31230 - Safety Zone; M.I.T.'s 150th Birthday Celebration Fireworks, Charles River, Boston, MA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-31

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; M.I.T.'s 150th Birthday Celebration...) Zone for the M.I.T.'s 150th Birthday Celebration Fireworks display. This safety zone is necessary to.... 165.T01-0375 to read as follows: Sec. 165.T01-0375 Safety Zone; M.I.T.'s 150th Birthday...

  9. Mit1 Transcription Factor Mediates Methanol Signaling and Regulates the Alcohol Oxidase 1 (AOX1) Promoter in Pichia pastoris.

    PubMed

    Wang, Xiaolong; Wang, Qi; Wang, Jinjia; Bai, Peng; Shi, Lei; Shen, Wei; Zhou, Mian; Zhou, Xiangshan; Zhang, Yuanxing; Cai, Menghao

    2016-03-18

    The alcohol oxidase 1 (AOX1) promoter (P AOX1) of Pichia pastoris is the most powerful and commonly used promoter for driving protein expression. However, mechanisms regulating its transcriptional activity are unclear. Here, we identified a Zn(II)2Cys6-type methanol-induced transcription factor 1 (Mit1) and elucidated its roles in regulating PAOX1 activity in response to glycerol and methanol. Mit1 regulated the expression of many genes involved in methanol utilization pathway, including AOX1, but did not participate in peroxisome proliferation and transportation of peroxisomal proteins during methanol metabolism. Structural analysis of Mit1 by performing domain deletions confirmed its specific and critical role in the strict repression of P AOX1 in glycerol medium. Importantly, Mit1, Mxr1, and Prm1, which positively regulated P AOX1 in response to methanol, were bound to P AOX1 at different sites and did not interact with each other. However, these factors cooperatively activated P AOX1 through a cascade. Mxr1 mainly functioned during carbon derepression, whereas Mit1 and Prm1 functioned during methanol induction, with Prm1 transmitting methanol signal to Mit1 by binding to the MIT1 promoter (P MIT1), thus increasingly expressing Mit1 and subsequently activating P AOX1.

  10. MIT Clean Energy Prize: Final Technical Report May 12, 2010 - May 11, 2011

    SciTech Connect

    Snyder, Chris; Campbell, Georgina; Salony, Jason; Aulet, Bill

    2011-08-09

    The MIT Clean Energy Prize (MIT CEP) is a venture creation and innovation competition to encourage innovation in the energy space, specifically with regard to clean energy. The Competition invited student teams from any US university to submit student-led ventures that demonstrate a high potential of successfully making clean energy more affordable, with a positive impact on the environment. By focusing on student ventures, the MIT CEP aims to educate the next generation of clean energy entrepreneurs. Teams receive valuable mentoring and hard deadlines that complement the cash prize to accelerate development of ventures. The competition is a year-long educational process that culminates in the selection of five category finalists and a Grand Prize winner and the distribution of cash prizes to each of those teams. Each entry was submitted in one of five clean energy categories: Renewables, Clean Non-Renewables, Energy Efficiency, Transportation, and Deployment.

  11. A New Tool for Inundation Modeling: Community Modeling Interface for Tsunamis (ComMIT)

    NASA Astrophysics Data System (ADS)

    Titov, V. V.; Moore, C. W.; Greenslade, D. J. M.; Pattiaratchi, C.; Badal, R.; Synolakis, C. E.; Kânoğlu, U.

    2011-11-01

    Almost 5 years after the 26 December 2004 Indian Ocean tragedy, the 10 August 2009 Andaman tsunami demonstrated that accurate forecasting is possible using the tsunami community modeling tool Community Model Interface for Tsunamis (ComMIT). ComMIT is designed for ease of use, and allows dissemination of results to the community while addressing concerns associated with proprietary issues of bathymetry and topography. It uses initial conditions from a precomputed propagation database, has an easy-to-interpret graphical interface, and requires only portable hardware. ComMIT was initially developed for Indian Ocean countries with support from the United Nations Educational, Scientific, and Cultural Organization (UNESCO), the United States Agency for International Development (USAID), and the National Oceanic and Atmospheric Administration (NOAA). To date, more than 60 scientists from 17 countries in the Indian Ocean have been trained and are using it in operational inundation mapping.

  12. MITR-III: Upgrade and relicensing studies for the MIT Research Reactor. Second annual report

    SciTech Connect

    Trosman, H.G.; Lanning, D.D.; Harling, O.K.

    1994-08-01

    The current operating license of the MIT research reactor will expire on May 7, 1996 or possibly a few years later if the US Nuclear Regulatory Commission agrees that the license period can start with the date of initial reactor operation. Driven by the imminent expiration of the operating license, a team of nuclear engineering staff and students have begun a study of the future options for the MIT Research Reactor. These options have included the range from a major rebuilding of the reactor to its decommissioning. This document reports the results of a two year intensive activity which has been supported by a $148,000 grant from the USDOE contract Number DEFG0293ER75859, approximately $100,000 of internal MIT funds and Nuclear Engineering Department graduate student fellowships as well as assistance from international visiting scientists and engineers.

  13. Fusion Science Outreach at the MIT Plasma Science and Fusion Center

    NASA Astrophysics Data System (ADS)

    Censabella, V.; Rivenberg, P.; Granville, J.; Nachtrieb, R.; Gangadhara, S.

    1997-11-01

    Educational Outreach at the MIT Plasma Science and Fusion Center is organized and energized by volunteers working together to increase the public's knowledge of fusion and plasma-related experiments. The PSFC holds a number of outreach activities throughout the year, such as Middle and High School Outreach Days. Included in these days is a demonstration of how magnets affect plasma using the ``Plasma Demo," an educational tool which will be on display for the first time outside the MIT area. Also featured is ``C-Mod Jr.," a video game which helps students discover how computers manipulate magnetic pulses to keep a plasma confined in the C-Mod tokamak for as long as possible. The PSFC maintains a Home Page on the World Wide Web, which can be reached at HTTP://PFC.MIT.EDU.

  14. Center for Multiscale Plasma Dynamics: Report on Activities (UCLA/MIT), 2009-2010

    SciTech Connect

    Troy Carter

    2011-04-18

    The final 'phaseout' year of the CMPD ended July 2010; a no cost extension was requested until May 2011 in order to enable the MIT subcontract funds to be fully utilized. Research progress over this time included verification and validation activities for the BOUT and BOUT++ code, studies of spontaneous reconnection in the VTF facility at MIT, and studies of the interaction between Alfven waves and drift waves in LAPD. The CMPD also hosted the 6th plasma physics winter school in 2010 (jointly with the NSF frontier center the Center for Magnetic Self-Organization, significant funding came from NSF for this most recent iteration of the Winter School).

  15. How Much Have They Retained? Making Unseen Concepts Seen in a Freshman Electromagnetism Course at MIT

    ERIC Educational Resources Information Center

    Dori, Yehudit Judy; Hult, Erin; Breslow, Lori; Belcher, John W.

    2007-01-01

    The introductory freshmen electromagnetism course at MIT has been taught since 2000 using a studio physics format entitled TEAL--Technology Enabled Active Learning. TEAL has created a collaborative, hands-on environment where students carry out desktop experiments, submit web-based assignments, and have access to a host of visualizations and…

  16. Graduate Training and Potential Employment for Political Scientists: The MIT Perspective.

    ERIC Educational Resources Information Center

    Altshuler, Alan

    This paper presents ideas on ways to help graduate students in political science to become more marketable for nonacademic positions. It also includes background information on the changing employment market for Ph.D.'s. These ideas were discussed at a 1980 meeting of teachers, graduate students, and recent Ph.D.'s at MIT. The purpose of the…

  17. Terror mit Atomwaffen: reale Gefahr? Nukleare und Radiologische Waffen

    NASA Astrophysics Data System (ADS)

    Harigel, Gert G.

    2006-01-01

    Können Terroristen sich nukleare Massenvernichtungswaffen beschaffen? Dazu müssten sie ausreichende Mengen an waffenfähigem, spaltbarem Material stehlen. Selbst der Bau einer primitiven Atombombe erfordert einen hohen technischen Aufwand und Spezialisten. Wahrscheinlicher ist deshalb der Diebstahl einer kleinen taktischen Kernwaffe. Alternativ könnten Terroristen sich radioaktives Material aus zivilen Quellen beschaffen und daraus eine Schmutzige Bombe bauen. Eine solche radiologische Waffe wäre keine echte Massenvernichtungswaffe, doch ihre psychologische Wirkung könnte stark sein. Das macht sie für Terroristen attraktiv, weswegen diese Gefahr ernst genommen werden muss.

  18. 77 FR 2096 - Proposal Review Panel for Materials Research; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ... Proposal Review Panel for Materials Research; Notice of Meeting In accordance with the Federal Advisory...: Name: Site visit review of the Materials Research Science and Engineering Center (MRSEC) at Massachusetts Institute of Technology (MIT) by the Division of Materials Research (DMR) 1203. Dates and...

  19. Nanomedical strategy to prolong survival period, heighten cure rate, and lower systemic toxicity of S180 mice treated with MTX/MIT

    PubMed Central

    Song, Ning; Zhao, Ming; Wang, Yuji; Hu, Xi; Wu, Jianhui; Jiang, Xueyun; Li, Shan; Cui, Chunying; Peng, Shiqi

    2016-01-01

    In spite of the usual combination form of methotrexate (MTX)/mitoxantrone (MIT) and various complex combination regimens of MTX/MIT with other anticancer drugs, the survival period, cure rate, and systemic toxicity still need to be improved. For this purpose, a nanostructured amino group-modified mesoporous silica nanoparticles (MSNN)−MTX/MIT was designed. In the preparation, the surface of mesoporous silica nanoparticles (MSNs) was modified with amino groups to form MSNN. The covalent modification of the amino groups on the surface of MSNN with MTX resulted in MSNN−MTX. The loading of MIT into the surface pores of MSNN−MTX produced nanostructured MSNN−MTX/MIT. Compared with the usual combination form (MTX/MIT), nanostructured MSNN−MTX/MIT increased the survival period greatly, heightened the cure rate to a great extent, and lowered the systemic toxicity of the treated S180 mice, significantly. These superior in vivo properties of nanostructured MSNN−MTX/MIT over the usual combination form (MTX/MIT) were correlated with the former selectively releasing MTX and MIT in tumor tissue and inside cancer cells in vitro. The chemical structure and the nanostructure of MSNN−MTX/MIT were characterized using infrared and differential scanning calorimeter spectra as well as transmission electron microscope images, respectively. PMID:27621591

  20. Nanomedical strategy to prolong survival period, heighten cure rate, and lower systemic toxicity of S180 mice treated with MTX/MIT

    PubMed Central

    Song, Ning; Zhao, Ming; Wang, Yuji; Hu, Xi; Wu, Jianhui; Jiang, Xueyun; Li, Shan; Cui, Chunying; Peng, Shiqi

    2016-01-01

    In spite of the usual combination form of methotrexate (MTX)/mitoxantrone (MIT) and various complex combination regimens of MTX/MIT with other anticancer drugs, the survival period, cure rate, and systemic toxicity still need to be improved. For this purpose, a nanostructured amino group-modified mesoporous silica nanoparticles (MSNN)−MTX/MIT was designed. In the preparation, the surface of mesoporous silica nanoparticles (MSNs) was modified with amino groups to form MSNN. The covalent modification of the amino groups on the surface of MSNN with MTX resulted in MSNN−MTX. The loading of MIT into the surface pores of MSNN−MTX produced nanostructured MSNN−MTX/MIT. Compared with the usual combination form (MTX/MIT), nanostructured MSNN−MTX/MIT increased the survival period greatly, heightened the cure rate to a great extent, and lowered the systemic toxicity of the treated S180 mice, significantly. These superior in vivo properties of nanostructured MSNN−MTX/MIT over the usual combination form (MTX/MIT) were correlated with the former selectively releasing MTX and MIT in tumor tissue and inside cancer cells in vitro. The chemical structure and the nanostructure of MSNN−MTX/MIT were characterized using infrared and differential scanning calorimeter spectra as well as transmission electron microscope images, respectively.

  1. Nanomedical strategy to prolong survival period, heighten cure rate, and lower systemic toxicity of S180 mice treated with MTX/MIT.

    PubMed

    Song, Ning; Zhao, Ming; Wang, Yuji; Hu, Xi; Wu, Jianhui; Jiang, Xueyun; Li, Shan; Cui, Chunying; Peng, Shiqi

    2016-01-01

    In spite of the usual combination form of methotrexate (MTX)/mitoxantrone (MIT) and various complex combination regimens of MTX/MIT with other anticancer drugs, the survival period, cure rate, and systemic toxicity still need to be improved. For this purpose, a nanostructured amino group-modified mesoporous silica nanoparticles (MSNN)-MTX/MIT was designed. In the preparation, the surface of mesoporous silica nanoparticles (MSNs) was modified with amino groups to form MSNN. The covalent modification of the amino groups on the surface of MSNN with MTX resulted in MSNN-MTX. The loading of MIT into the surface pores of MSNN-MTX produced nanostructured MSNN-MTX/MIT. Compared with the usual combination form (MTX/MIT), nanostructured MSNN-MTX/MIT increased the survival period greatly, heightened the cure rate to a great extent, and lowered the systemic toxicity of the treated S180 mice, significantly. These superior in vivo properties of nanostructured MSNN-MTX/MIT over the usual combination form (MTX/MIT) were correlated with the former selectively releasing MTX and MIT in tumor tissue and inside cancer cells in vitro. The chemical structure and the nanostructure of MSNN-MTX/MIT were characterized using infrared and differential scanning calorimeter spectra as well as transmission electron microscope images, respectively. PMID:27621591

  2. Quantenphysik Interferometrie von C70-Molekülen

    NASA Astrophysics Data System (ADS)

    Ziegler, Thomas

    2002-05-01

    Interferenzversuche mit Neutronen und schweren Atomen stellen kein großes Problem mehr dar, selbst die Welleneigenschaften von C60-und C70-Molekülen wurden bereits nachgewiesen. Allerdings stößt man bei der Realisation immer feinerer Gitter mit Gitterkonstanten von etwa 100 nm im Fall dieser Moleküle auf technische Probleme. Wissenschaftlern der Universität Wien ist es jüngst gelungen, ein so genanntes Talbot-Lau-Interferometer zu realisieren und die Welleneigenschaften von C70 mit einer bislang unerreichten Qualität nachzuweisen [1].

  3. The MIT Accelerator Laboratory for Diagnostic Development for OMEGA, Z and the NIF

    NASA Astrophysics Data System (ADS)

    Petrasso, R.; Gatu Johnson, M.; Armstrong, E.; Orozco, D.; Rinderknecht, H. G.; Rojas Herrera, J.; Rosenberg, M.; Sio, H.; Zylstra, A.; Frenje, J.; Li, C. K.; Seguin, F. H.; Hahn, K.; Jones, B.; Ruiz, C. L.; Sangster, T. C.

    2014-10-01

    The MIT Linear Electrostatic Ion Accelerator generates D-D and D-3He fusion products, which are used for development of nuclear diagnostics for OMEGA, Z, and the NIF. Fusion reaction rates around 106 s-1 are routinely achieved with this accelerator, and fluence and energy of the fusion products are accurately characterized. Diagnostics developed and calibrated at this facility include CR-39 based charged-particle spectrometers, neutron detectors, and the particle Time-Of-Flight (pTOF) CVD-diamond-based bang time detector. The accelerator is also a vital tool in the education of graduate and undergraduate students at MIT. This work was supported in part by SNL, DOE, LLE and LLNL.

  4. Educational Outreach at the M.I.T. Plasma Fusion Center

    NASA Astrophysics Data System (ADS)

    Censabella, V.

    1996-11-01

    Educational outreach at the MIT Plasma Fusion Center consists of volunteers working together to increase the public's knowledge of fusion and plasma-related experiments. Seeking to generate excitement about science, engineering and mathematics, the PFC holds a number of outreach activities throughout the year, such as Middle and High School Outreach Days. Outreach also includes the Mr. Magnet Program, which uses an interactive strategy to engage elementary school children. Included in this year's presentation will be a new and improved C-MOD Jr, a confinement video game which helps students to discover how computers manipulate magnetic pulses to keep a plasma confined for as long as possible. Also on display will be an educational toy created by the Cambridge Physics Outlet, a PFC spin-off company. The PFC maintains a Home Page on the World Wide Web, which can be reached at http://cmod2.pfc.mit.edu/.

  5. The neurosciences research program at MIT and the beginning of the modern field of neuroscience.

    PubMed

    Adelman, George

    2010-01-15

    The interdisciplinary field, "neuroscience," began at MIT in 1962 with the founding of the Neurosciences Research Program (NRP) by Francis O. Schmitt and a group of US and international scientists - physical, biological, medical, and behavioral - interested in understanding the brain basis of behavior and mind. They organized and held specialist meetings of basic topics in neuroscience, and the journal and book publications over the next 20 years, based on these meetings, helped establish the new field.

  6. The MIT high resolution X-ray spectroscopy instruments on AXAF

    NASA Astrophysics Data System (ADS)

    Canizares, C. R.; Dewey, D.; Galton, E. B.; Markert, T. H.; Smith, Henry I.; Schattenburg, M. L.; Woodgate, B. E.; Jordan, S.

    1992-03-01

    The general design and performance characteristics of MIT's two dispersive spectrometers, the Bragg Crystal Spectrometer (BCS) and the High Energy Transmission Grating Spectrometer (HETG), now being developed for the Advanced X-ray Astrophysics Facility (AXAF), are described. Particular attention is given to the development of the critical technologies incorporated into these instruments, including BCS diffractors, imaging gas flow proportional counters, and grating elements for the HETG. The principal stages and the current status of the developments are reviewed.

  7. Teleoperation experiments with a Utah/MIT hand and a VPL DataGlove

    NASA Technical Reports Server (NTRS)

    Clark, D.; Demmel, J.; Hong, J.; Lafferriere, Gerardo; Salkind, L.; Tan, X.

    1989-01-01

    A teleoperation system capable of controlling a Utah/MIT Dextrous Hand using a VPL DataGlove as a master is presented. Additionally the system is capable of running the dextrous hand in robotic (autonomous) mode as new programs are developed. The software and hardware architecture used is presented and the experiments performed are described. The communication and calibration issues involved are analyzed and applications to the analysis and development of automated dextrous manipulations are investigated.

  8. Gaussian frequency blending algorithm with matrix inversion tomosynthesis (MITS) and filtered back projection (FBP) for better digital breast tomosynthesis reconstruction

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Lo, Joseph Y.; Baker, Jay A.; Dobbins, James T., III

    2006-03-01

    Breast cancer is a major problem and the most common cancer among women. The nature of conventional mammpgraphy makes it very difficult to distinguish a cancer from overlying breast tissues. Digital Tomosynthesis refers to a three-dimensional imaging technique that allows reconstruction of an arbitrary set of planes in the breast from limited-angle series of projection images as the x-ray source moves. Several tomosynthesis algorithms have been proposed, including Matrix Inversion Tomosynthesis (MITS) and Filtered Back Projection (FBP) that have been investigated in our lab. MITS shows better high frequency response in removing out-of-plane blur, while FBP shows better low frequency noise propertities. This paper presents an effort to combine MITS and FBP for better breast tomosynthesis reconstruction. A high-pass Gaussian filter was designed and applied to three-slice "slabbing" MITS reconstructions. A low-pass Gaussian filter was designed and applied to the FBP reconstructions. A frequency weighting parameter was studied to blend the high-passed MITS with low-passed FBP frequency components. Four different reconstruction methods were investigated and compared with human subject images: 1) MITS blended with Shift-And-Add (SAA), 2) FBP alone, 3) FBP with applied Hamming and Gaussian Filters, and 4) Gaussian Frequency Blending (GFB) of MITS and FBP. Results showed that, compared with FBP, Gaussian Frequency Blending (GFB) has better performance for high frequency content such as better reconstruction of micro-calcifications and removal of high frequency noise. Compared with MITS, GFB showed more low frequency breast tissue content.

  9. MIT: A Future Mission to Investigate Magnetosphere-Ionosphere-Thermosphere Coupling with Multipoint Observations

    NASA Astrophysics Data System (ADS)

    Liu, Y.

    2015-12-01

    The Magnetosphere, Ionosphere and Thermosphere (MIT) mission is one of the Space Science Strategic Pioneer Projects of the Chinese Academy of Sciences (CAS). Its major scientific objectives focus on the heating, acceleration and transport processes of ions in the polar regions and on their impact on the ring current and radiation belts. Because of the dynamic nature of these processes that also vary with altitude, it is imperative to cover with MIT altitudes from a few 100 km to several earth radii. This will be accomplished with a novel constellation of four spacecraft in polar orbits that provide periodic simultaneous measurements in the polar regions at three different altitudes. The two Ionospheric spacecraft have a polar orbit of 500km*1500km. The other two spacecraft have symmetric polar orbits with geocentric distances of 2Re*8Re (Re is the radius of the Earth).With instrument packages covering particle and field measurements over a wide energy range on all four spacecraft we will be able to monitor and investigate all relevant processes, including ion outflow from the source region in the ionosphere, their acceleration at mid-altitudes, to their final destination in the magnetosphere. Presently, MIT is in the background study stage that will be completed in 2015, with the engineering stage planed to start in 2016, if selected.

  10. MIT: A Future Mission to Investigate Magnetosphere-Ionosphere-Thermosphere Coupling with Multipoint Observations

    NASA Astrophysics Data System (ADS)

    Liu, Yong; Wang, Chi; Xu, Jiyao; Li, Xiaoyu; Klecker, Berndt

    2015-04-01

    The Magnetosphere, Ionosphere and Thermosphere (MIT) mission is one of the Space Science Strategic Pioneer Projects of the Chinese Academy of Sciences (CAS). Its major scientific objectives focus on the heating, acceleration and transport processes of ions in the polar regions and on their impact on the ring current and radiation belts. Because of the dynamic nature of these processes that also vary with altitude, it is imperative to cover with MIT altitudes from a few 100 km to several earth radii. This will be accomplished with a novel constellation of four spacecraft in polar orbits that provide periodic simultaneous measurements in the polar regions at three different altitudes. The two Ionospheric spacecraft have a polar orbit of 500km*1500km. The other two spacecraft have symmetric polar orbits with geocentric distances of 2Re*8Re (Re is the radius of the Earth). With instrument packages covering particle and field measurements over a wide energy range on all four spacecraft we will be able to monitor and investigate all relevant processes, including ion outflow from the source region in the ionosphere, their acceleration at mid-altitudes, to their final destination in the magnetosphere. Presently, MIT is in the background study stage that will be completed in 2015, with the engineering stage planed to start in 2016, if selected.

  11. [COPD und Klangtherapie: Pilotstudie zur Wirksamkeit einer Behandlung mit Körpertambura bei COPD-Patienten].

    PubMed

    Hartwig, Bernhard; Schmidt, Stefan; Hartwig, Isabella

    2016-01-01

    Hintergrund: Erkrankungen der Atemorgane treten mit steigendem Alter öfter auf, nehmen weltweit zu und sind häufige Ursachen für Morbidität und Mortalität. In dieser Pilotstudie wurde der Frage nachgegangen, ob eine einmalige 10-minütige Behandlung mit einer Körpertambura eine signifikante und effektive Verbesserung der Lungenfunktion von Patienten mit chronisch-obstruktiver Lungenerkrankung (COPD; GOLD-Stadium A oder B) erbringen kann. Patienten und Methoden: 54 Probanden konnten je zur Hälfte in eine Behandlungsgruppe (Körpertambura) und eine aktive Kontrollgruppe (Atemtherapie) randomisiert werden. Eine Bestimmung der Lungenfunktionsmessparameter «Einsekundenkapazität» (FEV1) und «inspiratorische Vitalkapazität» (IVC) zu den Zeitpunkten T1 (Baseline), T2 (direkt nach Behandlung) und als Follow-up etwa 3 Wochen nach T1 (T3). Ergebnisse: Die Behandlungsgruppe zeigte sich der Kontrollgruppe in beiden Werten signifikant überlegen. Die Zeit-×-Gruppe-Interaktion (Varianzanalyse) ergab p = 0,001 (FEV1) bzw. p = 0,04 (IVC). Die Behandlungsgruppe zeigte bei beiden Werten eine Verbesserung von klinischer Relevanz. Schlussfolgerung: Diese Ergebnisse zeigen, dass die Klangbehandlung mittels einer Körpertambura - neben den schulmedizinischen, leitliniengerechten Therapien - eine zusätzliche, nebenwirkungsarme, aber durchaus klinisch wirksame Option für die Behandlung von COPD-Patienten darstellen kann, um deren Lebensqualität zu stabilisieren und zu verbessern. PMID:27606616

  12. Massachusetts Beryllium Screening Program for Former Workers of Wyman-Gordon, Norton Abrasives, and MIT/Nuclear Metals

    SciTech Connect

    Pepper, L. D.

    2008-05-21

    The overall objective of this project was to provide medical screening to former workers of Wyman-Gordon Company, Norton Abrasives, and MIT/Nuclear Metals (NMI) in order to prevent and minimize the health impact of diseases caused by site related workplace exposures to beryllium. The program was developed in response to a request by the U.S. Department of Energy (DOE) that had been authorized by Congress in Section 3162 of the 1993 Defense Authorization Act, urging the DOE to carry out a program for the identification and ongoing evaluation of current and former DOE employees who are subjected to significant health risks during such employment." This program, funded by the DOE, was an amendment to the medical surveillance program for former DOE workers at the Nevada Test Site (NTS). This program's scope included workers who had worked for organizations that provided beryllium products or materials to the DOE as part of their nuclear weapons program. These organizations have been identified as Beryllium Vendors.

  13. Teaching practical leadership in MIT satellite development class: CASTOR and Exoplanet projects

    NASA Astrophysics Data System (ADS)

    Babuscia, Alessandra; Craig, Jennifer L.; Connor, Jane A.

    2012-08-01

    For more than a decade, the Aeronautics and Astronautics Department at MIT has offered undergraduate students the opportunity of conceiving, developing, implementing and operating new spacecraft's missions. During a three term class, junior and senior students experience all the challenges of a true engineering team project: design, analysis, testing, technical documentation development, team management, and leadership. Leadership instruction is an important part of the curricula; through the development of leadership skills, students learn to manage themselves and each other in a more effective way, increasing the overall productivity of the team. Also, a strong leadership education is a key factor in improving the abilities of future engineers to be effective team members and leaders in the companies and agencies in which they will work. However, too often leadership instruction is presented in an abstract way, which does not provide students with suggestions for immediate applicability. As a consequence, students underestimate the potential that leadership education can have on the development of their projects. To counteract that effect, a new approach for teaching "practical" leadership has been developed. This approach is composed of a set of activities developed to improve students' leadership skills in the context of a project. Specifically, this approach has been implemented in the MIT satellite development class. In that class, students experienced the challenges of building two satellites: CASTOR and Exoplanet. These two missions are real space projects which will be launched in the next two years, and which involve cooperation with different entities (MIT, NASA, and Draper). Hence, the MIT faculty was interested in developing leadership activities to improve the productivity of the teams in a short time. In fact, one of the key aspects of the approach proposed is that it can be quickly implemented in a single semester, requiring no more than 4 h of

  14. Deletion of PdMit1, a homolog of yeast Csg1, affects growth and Ca(2+) sensitivity of the fungus Penicillium digitatum, but does not alter virulence.

    PubMed

    Zhu, Congyi; Wang, Weili; Wang, Mingshuang; Ruan, Ruoxin; Sun, Xuepeng; He, Meixian; Mao, Cungui; Li, Hongye

    2015-04-01

    GDP-mannose:inositol-phosphorylceramide (MIPC) and its derivatives are important for Ca(2+) sensitization of Saccharomyces cerevisiae and for the virulence of Candida albicans, but its role in the virulence of plant fungal pathogens remains unclear. In this study, we report the identification and functional characterization of PdMit1, the gene encoding MIPC synthase in Penicillium digitatum, one of the most important pathogens of postharvest citrus fruits. To understand the function of PdMit1, a PdMit1 deletion mutant was generated. Compared to its wild-type control, the PdMit1 deletion mutant exhibited slow radial growth, decreased conidia production and delayed conidial germination, suggesting that PdMit1 is important for the growth of mycelium, sporulation and conidial germination. The PdMit1 deletion mutant also showed hypersensitivity to Ca(2+). Treatment with 250 mmol/l Ca(2+) induced vacuole fusion in the wild-type strain, but not in the PdMit1 deletion mutant. Treatment with 250mmol/lCaCl2 upregulated three Ca(2+)-ATPase genes in the wild-type strain, and this was significantly inhibited in the PdMit1 deletion mutant. These results suggest that PdMit1 may have a role in regulating vacuole fusion and expression of Ca(2+)-ATPase genes by controlling biosynthesis of MIPC, and thereby imparts P. digitatum Ca(2+) tolerance. However, we found that PdMit1 is dispensable for virulence of P. digitatum.

  15. Prospective pilot trial of PerMIT versus standard anticoagulation service management of patients initiating oral anticoagulation.

    PubMed

    Borgman, Mark P; Pendleton, Robert C; McMillin, Gwendolyn A; Reynolds, Kristen K; Vazquez, Sara; Freeman, Andrew; Wilson, Andrew; Valdes, Roland; Linder, Mark W

    2012-09-01

    We performed a randomised pilot trial of PerMIT, a novel decision support tool for genotype-based warfarin initiation and maintenance dosing, to assess its efficacy for improving warfarin management. We prospectively studied 26 subjects to compare PerMIT-guided management with routine anticoagulation service management. CYP2C9 and VKORC1 genotype results for 13 subjects randomly assigned to the PerMIT arm were recorded within 24 hours of enrolment. To aid in INR interpretation, PerMIT calculates estimated loading and maintenance doses based on a patient's genetic and clinical characteristics and displays calculated S-warfarin plasma concentrations based on planned or administered dosages. In comparison to control subjects, patients in the PerMIT study arm demonstrated a 3.6-day decrease in the time to reach a stabilised INR within the target therapeutic range (4.7 vs. 8.3 days, p = 0.015); a 12.8% increase in time spent within the therapeutic interval over the first 25 days of therapy (64.3% vs. 55.3%, p = 0.180); and a 32.9% decrease in the frequency of warfarin dose adjustments per INR measurement (38.3% vs. 57.1%, p = 0.007). Serial measurements of plasma S-warfarin concentrations were also obtained to prospectively evaluate the accuracy of the pharmacokinetic model during induction therapy. The PerMIT S-warfarin plasma concentration model estimated 62.8% of concentrations within 0.15 mg/l. These pilot data suggest that the PerMIT method and its incorporation of genotype/phenotype information may help practitioners increase the safety, efficacy, and efficiency of warfarin therapeutic management. PMID:22836303

  16. MitProNet: A knowledgebase and analysis platform of proteome, interactome and diseases for mammalian mitochondria.

    PubMed

    Wang, Jiabin; Yang, Jian; Mao, Song; Chai, Xiaoqiang; Hu, Yuling; Hou, Xugang; Tang, Yiheng; Bi, Cheng; Li, Xiao

    2014-01-01

    Mitochondrion plays a central role in diverse biological processes in most eukaryotes, and its dysfunctions are critically involved in a large number of diseases and the aging process. A systematic identification of mitochondrial proteomes and characterization of functional linkages among mitochondrial proteins are fundamental in understanding the mechanisms underlying biological functions and human diseases associated with mitochondria. Here we present a database MitProNet which provides a comprehensive knowledgebase for mitochondrial proteome, interactome and human diseases. First an inventory of mammalian mitochondrial proteins was compiled by widely collecting proteomic datasets, and the proteins were classified by machine learning to achieve a high-confidence list of mitochondrial proteins. The current version of MitProNet covers 1124 high-confidence proteins, and the remainders were further classified as middle- or low-confidence. An organelle-specific network of functional linkages among mitochondrial proteins was then generated by integrating genomic features encoded by a wide range of datasets including genomic context, gene expression profiles, protein-protein interactions, functional similarity and metabolic pathways. The functional-linkage network should be a valuable resource for the study of biological functions of mitochondrial proteins and human mitochondrial diseases. Furthermore, we utilized the network to predict candidate genes for mitochondrial diseases using prioritization algorithms. All proteins, functional linkages and disease candidate genes in MitProNet were annotated according to the information collected from their original sources including GO, GEO, OMIM, KEGG, MIPS, HPRD and so on. MitProNet features a user-friendly graphic visualization interface to present functional analysis of linkage networks. As an up-to-date database and analysis platform, MitProNet should be particularly helpful in comprehensive studies of complicated

  17. Efficient Heat Storage Materials: Metallic Composites Phase-Change Materials for High-Temperature Thermal Energy Storage

    SciTech Connect

    2011-11-21

    HEATS Project: MIT is developing efficient heat storage materials for use in solar and nuclear power plants. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun’s not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. MIT is designing nanostructured heat storage materials that can store a large amount of heat per unit mass and volume. To do this, MIT is using phase change materials, which absorb a large amount of latent heat to melt from solid to liquid. MIT’s heat storage materials are designed to melt at high temperatures and conduct heat well—this makes them efficient at storing and releasing heat and enhances the overall efficiency of the thermal storage and energy-generation process. MIT’s low-cost heat storage materials also have a long life cycle, which further enhances their efficiency.

  18. Regional climate projection of the Maritime Continent using the MIT Regional Climate Model

    NASA Astrophysics Data System (ADS)

    IM, E. S.; Eltahir, E. A. B.

    2014-12-01

    Given that warming of the climate system is unequivocal (IPCC AR5), accurate assessment of future climate is essential to understand the impact of climate change due to global warming. Modelling the climate change of the Maritime Continent is particularly challenge, showing a high degree of uncertainty. Compared to other regions, model agreement of future projections in response to anthropogenic emission forcings is much less. Furthermore, the spatial and temporal behaviors of climate projections seem to vary significantly due to a complex geographical condition and a wide range of scale interactions. For the fine-scale climate information (27 km) suitable for representing the complexity of climate change over the Maritime Continent, dynamical downscaling is performed using the MIT regional climate model (MRCM) during two thirty-year period for reference (1970-1999) and future (2070-2099) climate. Initial and boundary conditions are provided by Community Earth System Model (CESM) simulations under the emission scenarios projected by MIT Integrated Global System Model (IGSM). Changes in mean climate as well as the frequency and intensity of extreme climate events are investigated at various temporal and spatial scales. Our analysis is primarily centered on the different behavior of changes in convective and large-scale precipitation over land vs. ocean during dry vs. wet season. In addition, we attempt to find the added value to downscaled results over the Maritime Continent through the comparison between MRCM and CESM projection. Acknowledgements.This research was supported by the National Research Foundation Singapore through the Singapore MIT Alliance for Research and Technology's Center for Environmental Sensing and Modeling interdisciplinary research program.

  19. Sampling Technique for Robust Odorant Detection Based on MIT RealNose Data

    NASA Technical Reports Server (NTRS)

    Duong, Tuan A.

    2012-01-01

    This technique enhances the detection capability of the autonomous Real-Nose system from MIT to detect odorants and their concentrations in noisy and transient environments. The lowcost, portable system with low power consumption will operate at high speed and is suited for unmanned and remotely operated long-life applications. A deterministic mathematical model was developed to detect odorants and calculate their concentration in noisy environments. Real data from MIT's NanoNose was examined, from which a signal conditioning technique was proposed to enable robust odorant detection for the RealNose system. Its sensitivity can reach to sub-part-per-billion (sub-ppb). A Space Invariant Independent Component Analysis (SPICA) algorithm was developed to deal with non-linear mixing that is an over-complete case, and it is used as a preprocessing step to recover the original odorant sources for detection. This approach, combined with the Cascade Error Projection (CEP) Neural Network algorithm, was used to perform odorant identification. Signal conditioning is used to identify potential processing windows to enable robust detection for autonomous systems. So far, the software has been developed and evaluated with current data sets provided by the MIT team. However, continuous data streams are made available where even the occurrence of a new odorant is unannounced and needs to be noticed by the system autonomously before its unambiguous detection. The challenge for the software is to be able to separate the potential valid signal from the odorant and from the noisy transition region when the odorant is just introduced.

  20. Lasers, their development, and applications at M.I.T. Lincoln Laboratory

    NASA Technical Reports Server (NTRS)

    Rediker, R. H.; Melngailis, I.; Mooradian, A.

    1984-01-01

    A historical account of the work on lasers at MIT Lincoln Laboratory is presented. Highlighted are the efforts that led to the coinvention of the semiconductor laser and the Laboratory's later role in establishing the feasibility of GaInAsP/InP semiconductor lasers for use in fiber telecommunications at 1.3-1.5 micron wavelengths. Descriptions of other important developments include tunable lead-salt semiconductor and solid-state lasers for spectroscopy and LIDAR applications, respectively, as well as ultrastable CO2 lasers for coherent infrared radar.

  1. MitBASE : a comprehensive and integrated mitochondrial DNA database. The present status

    PubMed Central

    Attimonelli, M.; Altamura, N.; Benne, R.; Brennicke, A.; Cooper, J. M.; D’Elia, D.; Montalvo, A. de; Pinto, B. de; De Robertis, M.; Golik, P.; Knoop, V.; Lanave, C.; Lazowska, J.; Licciulli, F.; Malladi, B. S.; Memeo, F.; Monnerot, M.; Pasimeni, R.; Pilbout, S.; Schapira, A. H. V.; Sloof, P.; Saccone, C.

    2000-01-01

    MitBASE is an integrated and comprehensive database of mitochondrial DNA data which collects, under a single interface, databases for Plant, Vertebrate, Invertebrate, Human, Protist and Fungal mtDNA and a Pilot database on nuclear genes involved in mitochondrial biogenesis in Saccharomyces cerevisiae. MitBASE reports all available information from different organisms and from intraspecies variants and mutants. Data have been drawn from the primary databases and from the literature; value adding information has been structured, e.g., editing information on protist mtDNA genomes, pathological information for human mtDNA variants, etc. The different databases, some of which are structured using commercial packages (Microsoft Access, File Maker Pro) while others use a flat-file format, have been integrated under ORACLE. Ad hoc retrieval systems have been devised for some of the above listed databases keeping into account their peculiarities. The database is resident at the EBI and is available at the following site: http://www3.ebi.ac.uk/Research/Mitbase/mitbase.pl . The impact of this project is intended for both basic and applied research. The study of mitochondrial genetic diseases and mitochondrial DNA intraspecies diversity are key topics in several biotechnological fields. The database has been funded within the EU Biotechnology programme. PMID:10592207

  2. Evaluation of Dynamics of the West African Monsoon Jump Simulated by the MIT Regional Climate Model

    NASA Astrophysics Data System (ADS)

    Eltahir, Elfatih A. B.; Im, Eun-Soon

    2015-04-01

    The seasonal advance and retreat of the West African monsoon behaves abrupt northward jump of maximum rainfall from the Guinean coast to the Sahel region. Both global and regional climate models have difficulties in accurately reproducing such a behavior due to its complexity combined the dynamical and physical processes. In this study, we evaluate the performance of the MIT Regional Climate Model (MRCM) in simulating the West African monsoon. For this, 20-year long-term simulation (1989-2008) is performed using the ERAInterim reanalysis as the initial and boundary condition, and the analysis primarily focuses on the dynamics associated with abrupt phase transitions of the monsoon rainfall. We first examine detailed characteristics in terms of the onset, maximum, and retreat of the monsoon rainfall using daily precipitation. We then present the dynamical explanation behind rainfall variability from the analysis of the absolute vorticity near the tropopause and the meridional gradient of boundary-layer entropy within the dynamical theory proposed by Eltahir and Gong (1996). Acknowledgements : This research was supported by the National Research Foundation Singapore through the Singapore MIT Alliance for Research and Technology's Center for Environmental Sensing and Modeling interdisciplinary research program.

  3. Identifikationsverfahren zur Analyse von EEG-Signalen bei Epilepsie mit Reaktions-Diffusions Netzwerken

    NASA Astrophysics Data System (ADS)

    Gollas, F.; Tetzlaff, R.

    2007-06-01

    Partielle Differentialgleichungen des Reaktions-Diffusions-Typs beschreiben Phänomene wie Musterbildung, nichtlineare Wellenausbreitung und deterministisches Chaos und werden oft zur Untersuchung komplexer Vorgänge auf den Gebieten der Biologie, Chemie und Physik herangezogen. Zellulare Nichtlineare Netzwerke (CNN) sind eine räumliche Anordnung vergleichsweise einfacher dynamischer Systeme, die eine lokale Kopplung untereinander aufweisen. Durch eine Diskretisierung der Ortsvariablen können Reaktions-Diffusions-Gleichungen häufig auf CNN mit nichtlinearen Gewichtsfunktionen abgebildet werden. Die resultierenden Reaktions-Diffusions-CNN (RD-CNN) weisen dann in ihrer Dynamik näherungsweise gleiches Verhalten wie die zugrunde gelegten Reaktions-Diffusions-Systeme auf. Werden RD-CNN zur Identifikation neuronaler Strukturen anhand von EEG-Signalen herangezogen, so besteht die Möglichkeit festzustellen, ob das gefundene Netzwerk lokale Aktivität aufweist. Die von Chua eingeführte Theorie der lokalen Aktivität Chua (1998); Dogaru und Chua (1998) liefert eine notwendige Bedingung für das Auftreten von emergentem Verhalten in zellularen Netzwerken. Änderungen in den Parametern bestimmter RD-CNN könnten auf bevorstehende epileptische Anfälle hinweisen. In diesem Beitrag steht die Identifikation neuronaler Strukturen anhand von EEG-Signalen durch Reaktions-Diffusions-Netzwerke im Vordergrund der dargestellten Untersuchungen. In der Ergebnisdiskussion wird insbesondere auch die Frage nach einer geeigneten Netzwerkstruktur mit minimaler Komplexität behandelt.

  4. How Much Have They Retained? Making Unseen Concepts Seen in a Freshman Electromagnetism Course at MIT

    NASA Astrophysics Data System (ADS)

    Dori, Yehudit Judy; Hult, Erin; Breslow, Lori; Belcher, John W.

    2007-08-01

    The introductory freshmen electromagnetism course at MIT has been taught since 2000 using a studio physics format entitled TEAL—Technology Enabled Active Learning. TEAL has created a collaborative, hands-on environment where students carry out desktop experiments, submit web-based assignments, and have access to a host of visualizations and simulations. These learning tools help them visualize unseen electromagnetic concepts and develop stronger intuition about related phenomena. A previous study has shown that students who took the course in the TEAL format (the experimental group) gained significantly better conceptual understanding than those who took it in the traditional lecture-recitation format (the control group). The present longitudinal study focuses on the extent to which these two research groups (experimental and control) retain conceptual understanding about a year to 18 months after finishing the course. It also examines students attitudes about whether the teaching format (TEAL or traditional) contributes to their learning in advanced courses. Our research has indicated that the long-term effect of the TEAL course on students' retention of concepts was significantly stronger than that of the traditional course. This research is significant because it documents the long-term cognitive and affective impact of the TEAL studio physics format on learning outcomes of MIT students.

  5. Distinct mechanisms of recognizing endosomal sorting complex required for transport III (ESCRT-III) protein IST1 by different microtubule interacting and trafficking (MIT) domains.

    PubMed

    Guo, Emily Z; Xu, Zhaohui

    2015-03-27

    The endosomal sorting complex required for transport (ESCRT) machinery is responsible for membrane remodeling in a number of biological processes including multivesicular body biogenesis, cytokinesis, and enveloped virus budding. In mammalian cells, efficient abscission during cytokinesis requires proper function of the ESCRT-III protein IST1, which binds to the microtubule interacting and trafficking (MIT) domains of VPS4, LIP5, and Spartin via its C-terminal MIT-interacting motif (MIM). Here, we studied the molecular interactions between IST1 and the three MIT domain-containing proteins to understand the structural basis that governs pairwise MIT-MIM interaction. Crystal structures of the three molecular complexes revealed that IST1 binds to the MIT domains of VPS4, LIP5, and Spartin using two different mechanisms (MIM1 mode versus MIM3 mode). Structural comparison revealed that structural features in both MIT and MIM contribute to determine the specific binding mechanism. Within the IST1 MIM sequence, two phenylalanine residues were shown to be important in discriminating MIM1 versus MIM3 binding. These observations enabled us to deduce a preliminary binding code, which we applied to provide CHMP2A, a protein that normally only binds the MIT domain in the MIM1 mode, the additional ability to bind the MIT domain of Spartin in the MIM3 mode.

  6. Deletion of PdMit1, a homolog of yeast Csg1, affects growth and Ca2+ sensitivity of the fungus Penicillium digitatum, but does not alter virulence

    PubMed Central

    Zhu, Congyi; Wang, Weili; Wang, Mingshuang; Ruan, Ruoxin; Sun, Xuepeng; He, Meixian; Mao, Cungui; Li, Hongye

    2015-01-01

    GDP-mannose:inositol-phosphorylceramide (MIPC) and its derivatives are important for Ca2+ sensitization of Saccharomyces cerevisiae and for the virulence of Candida albicans, but its role in the virulence of plant fungal pathogens remains unclear. In this study, we report the identification and functional characterization of PdMit1, the gene encoding MIPC synthase in Penicillium digitatum, one of the most important pathogens of postharvest citrus fruits. To understand the function of PdMit1, a PdMit1 deletion mutant was generated. Compared to its wild-type control, the PdMit1 deletion mutant exhibited slow radial growth, decreased conidia production and delayed conidial germination, suggesting that PdMit1 is important for the growth of mycelium, sporulation and conidial germination. The PdMit1 deletion mutant also showed hypersensitivity to Ca2+. Treatment with 250 mmol/l Ca2+ induced vacuole fusion in the wild-type strain, but not in the PdMit1 deletion mutant. Treatment with 250 mmol/lCaCl2 upregulated three Ca2+-ATPase genes in the wild-type strain, and this was significantly inhibited in the PdMit1 deletion mutant. These results suggest that PdMit1 may have a role in regulating vacuole fusion and expression of Ca2+-ATPase genes by controlling biosynthesis of MIPC, and thereby imparts P. digitatum Ca2+ tolerance. However, we found that PdMit1 is dispensable for virulence of P. digitatum. PMID:25725383

  7. Draft Genome Sequences of Supercritical CO2-Tolerant Bacteria Bacillus subterraneus MITOT1 and Bacillus cereus MIT0214.

    PubMed

    Peet, Kyle C; Thompson, Janelle R

    2015-01-01

    We report draft genome sequences of Bacillus subterraneus MITOT1 and Bacillus cereus MIT0214 isolated through enrichment of samples from geologic sequestration sites in pressurized bioreactors containing a supercritical (sc) CO2 headspace. Their genome sequences expand the phylogenetic range of sequenced bacilli and allow characterization of molecular mechanisms of scCO2 tolerance.

  8. Evaluation of the MIT RMID 1000 system for the identification of Listeria species:AOAC performance tested method 090325

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The MIT 1000 RMID System is a rapid microbial identification device that uses the principles of light scattering coupled with proprietary algorithms to identify bacteria after being cultured and placed in a vial of filtered water. This specific method is for pure culture identification of Listeria ...

  9. Interactive Web-Based and Hands-On Engineering Education: A Freshman Aerospace Design Course at MIT.

    ERIC Educational Resources Information Center

    Newman, Dava J.

    "Introduction to Aerospace and Design" is a 3-hour per week freshman elective course at Massachusetts Institute of Technology (MIT) that culminates in a Lighter-Than-Air (LTA) vehicle design competition, exposing freshmen to the excitement of aerospace engineering design typically taught in the junior or senior years. In addition to the hands-on…

  10. Excellence in Research: Creative Organizational Responses at Berkeley, Harvard, MIT, and Stanford. ASHE 1985 Annual Meeting Paper.

    ERIC Educational Resources Information Center

    Gardiner, John J.

    Research environments of four leading universities were studied: University of California at Berkeley (UC-Berkeley), Harvard University, Massachusetts Institute of Technology (MIT), and Stanford University. Attention was directed to organizational responses for encouraging collaboration in research at these leading universities, as well as to…

  11. Rapid identification of Listeria spp.: an AOAC performance test of the MIT 1000 rapid microbial identification system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods that rapidly confirm the identification of foodborne pathogens are highly desired. The Micro Imaging Technology (MIT) 1000 Rapid Microbial Identification (RMID) System is a benchtop instrument that detects laser light scattered from individual bacterial cells in solution with an array of 35 ...

  12. Understanding the Self-Directed Online Learning Preferences, Goals, Achievements, and Challenges of MIT OpenCourseWare Subscribers

    ERIC Educational Resources Information Center

    Bonk, Curtis J.; Lee, Mimi Miyoung; Kou, Xiaojing; Xu, Shuya; Sheu, Feng-Ru

    2015-01-01

    This research targeted the learning preferences, goals and motivations, achievements, challenges, and possibilities for life change of self-directed online learners who subscribed to the monthly OpenCourseWare (OCW) e-newsletter from MIT. Data collection included a 25-item survey of 1,429 newsletter subscribers; 613 of whom also completed an…

  13. Trouble and Triumph: German Life-Turkish Tradition in Renan Demirkan's "Schwarzer Tee mit drei Stuck Zucker"

    ERIC Educational Resources Information Center

    Ebert, Reika

    2004-01-01

    This paper explores Demirkan's narrative strategies in "Schwarzer Tee mit drei Stuck Zucker" to negotiate issues of a life between two cultures and traditions. Based on Bhabha's insights that mainstream culture needs intellectual and artistic infusion from the margins of a society in order to remain vital; and that cultural production itself is a…

  14. Whistler mode based explanation for the fast reconnection rate measured in the mit versatile toroidal facility.

    PubMed

    Singh, Nagendra

    2011-12-01

    Despite the widely discussed role of whistler waves in mediating magnetic reconnection (MR), the direct connection between such waves and the MR has not been demonstrated by comparing the characteristic temporal and spatial features of the waves and the MR process. Using the whistler wave dispersion relation, we theoretically predict the experimentally measured rise time (τ(rise)) of a few microseconds for the fast rising MR rate in the Versatile Toroidal Facility at MIT. The rise time is closely given by the inverse of the frequency bandwidth of the whistler waves generated in the evolving current sheet. The wave frequencies lie much above the ion cyclotron frequency, but they are limited to less than 0.1% of the electron cyclotron frequency in the argon plasma. The maximum normalized MR rate R=0.35 measured experimentally is precisely predicted by the angular dispersion of the whistler waves.

  15. Oncogenic MITF dysregulation in clear cell sarcoma: defining the MiT family of human cancers.

    PubMed

    Davis, Ian J; Kim, Jessica J; Ozsolak, Fatih; Widlund, Hans R; Rozenblatt-Rosen, Orit; Granter, Scott R; Du, Jinyan; Fletcher, Jonathan A; Denny, Christopher T; Lessnick, Stephen L; Linehan, W Marston; Kung, Andrew L; Fisher, David E

    2006-06-01

    Clear cell sarcoma (CCS) harbors a pathognomonic chromosomal translocation fusing the Ewing's sarcoma gene (EWS) to the CREB family transcription factor ATF1 and exhibits melanocytic features. We show that EWS-ATF1 occupies the MITF promoter, mimicking melanocyte-stimulating hormone (MSH) signaling to induce expression of MITF, the melanocytic master transcription factor and an amplified oncogene in melanoma. Knockdown/rescue studies revealed that MITF mediates the requirement of EWS-ATF1 for CCS survival in vitro and in vivo as well as for melanocytic differentiation. Moreover, MITF and TFE3 reciprocally rescue one another in lines derived from CCS or pediatric renal carcinoma. Seemingly unrelated tumors thus employ distinct strategies to oncogenically dysregulate the MiT family, collectively broadening the definition of MiT-associated human cancers.

  16. VDI-Richtlinien - mit Technischen Regeln Wirtschaftlichkeit erhöhen und Standards setzen

    NASA Astrophysics Data System (ADS)

    Mandelartz, Johannes

    Der Verein Deutscher Ingenieure e.V. (VDI) ist ein gemeinnütziger, wirtschaftlich und politisch unabhängiger, technisch-wissenschaftlicher Verein von Ingenieuren und Naturwissenschaftlern. Mit über 137 000 persönlich zugeordneten Mitgliedern ist er eine der größten Ingenieur-Vereinigungen Europas und gilt in Deutschland als führender Sprecher der Technik und der Ingenieure. 1856 gegründet, hat er viele für die Technik wesentliche Entwicklungen in Gang gesetzt, so im Bereich der technischen Überwachung, der technischen Regelsetzung und Normung, der Arbeitsstudien, im gewerblichen Rechtsschutz und im Patentwesen. Seit seiner Gründung sieht es der VDI als seine Aufgabe, "das Zusammenwirken aller geistiger Kräfte der Technik im Bewusstsein ethischer Verantwortung zu fördern“ und die Lebensmöglichkeiten aller Menschen durch Entwicklung und sinnvoller Anwendung technischer Mittel zu verbessern.

  17. MIT-NASA/KSC space life science experiments - A telescience testbed

    NASA Technical Reports Server (NTRS)

    Oman, Charles M.; Lichtenberg, Byron K.; Fiser, Richard L.; Vordermark, Deborah S.

    1990-01-01

    Experiments performed at MIT to better define Space Station information system telescience requirements for effective remote coaching of astronauts by principal investigators (PI) on the ground are described. The experiments were conducted via satellite video, data, and voice links to surrogate crewmembers working in a laboratory at NASA's Kennedy Space Center. Teams of two PIs and two crewmembers performed two different space life sciences experiments. During 19 three-hour interactive sessions, a variety of test conditions were explored. Since bit rate limits are necessarily imposed on Space Station video experiments surveillance video was varied down to 50 Kb/s and the effectiveness of PI controlled frame rate, resolution, grey scale, and color decimation was investigated. It is concluded that remote coaching by voice works and that dedicated crew-PI voice loops would be of great value on the Space Station.

  18. Die Struktur von schlankem Materialfluss mit Lean Production Kanban und Innovationen

    NASA Astrophysics Data System (ADS)

    Scheid, Wolf-Michael

    In der Literatur wird Materialfluss überwiegend in Spezialdisziplinen betrachtet, etwa der Steuerungslogik, der Logistiktechnik oder dem Supply Chain Management. Ein charakterisierendes Merkmal des Materialflusses ist jedoch, dass er sich aus vielfältigen Einzelbausteinen zusammensetzt, die alle harmonisch abgestimmt sein müssen. Die maximal erreichbare Effizienz wird nicht durch Höchstleistungen in dem einen oder anderen Spezialthema bestimmt, sondern durch das schwächste Glied im gesamten komplexen Netzwerk. Den Schnittstellen zwischen den betroffenen Fachbereichen in einem Unternehmen kommt hier eine ganz besondere Bedeutung zu: Erst ein harmonischer Einklang ermöglicht hohe Effektivität. Dies setzt umfassendes Verständnis für interdisziplinäre Notwendigkeiten, ein hohes Maß an Abstimmung mit den operativen Prozessen und letztlich einen einvernehmlichen Umgang und den Respekt vor den Problemstellungen des Anderen voraus.

  19. Space applications of the MITS electron-photon Monte Carlo transport code system

    SciTech Connect

    Kensek, R.P.; Lorence, L.J.; Halbleib, J.A.; Morel, J.E.

    1996-07-01

    The MITS multigroup/continuous-energy electron-photon Monte Carlo transport code system has matured to the point that it is capable of addressing more realistic three-dimensional adjoint applications. It is first employed to efficiently predict point doses as a function of source energy for simple three-dimensional experimental geometries exposed to simulated uniform isotropic planar sources of monoenergetic electrons up to 4.0 MeV. Results are in very good agreement with experimental data. It is then used to efficiently simulate dose to a detector in a subsystem of a GPS satellite due to its natural electron environment, employing a relatively complex model of the satellite. The capability for survivability analysis of space systems is demonstrated, and results are obtained with and without variance reduction.

  20. MC21 analysis of the MIT PWR benchmark: Hot zero power results

    SciTech Connect

    Kelly Iii, D. J.; Aviles, B. N.; Herman, B. R.

    2013-07-01

    MC21 Monte Carlo results have been compared with hot zero power measurements from an operating pressurized water reactor (PWR), as specified in a new full core PWR performance benchmark from the MIT Computational Reactor Physics Group. Included in the comparisons are axially integrated full core detector measurements, axial detector profiles, control rod bank worths, and temperature coefficients. Power depressions from grid spacers are seen clearly in the MC21 results. Application of Coarse Mesh Finite Difference (CMFD) acceleration within MC21 has been accomplished, resulting in a significant reduction of inactive batches necessary to converge the fission source. CMFD acceleration has also been shown to work seamlessly with the Uniform Fission Site (UFS) variance reduction method. (authors)

  1. Rapid Speech Transmission Index predictions and auralizations of unusual instructional spaces at MIT's new Stata Center

    NASA Astrophysics Data System (ADS)

    Conant, David A.

    2005-04-01

    The Stata Center for Computer, Information and Intelligence Sciences, recently opened at the Massachusetts Institute of Technology, includes a variety of oddly-shaped seminar rooms in addition to lecture spaces of somewhat more conventional form. The architects design approach prohibited following conventional, well understood room-acoustical behavior yet MIT and the design team were keenly interested in ensuring that these spaces functioned exceptionally well, acoustically. CATT-Acoustic room modeling was employed to assess RASTI through multiple design iterations for all these spaces. Presented here are computational and descriptive results achieved for these rooms which are highly-regarded by faculty. They all sound peculiarly good, given their unusual form. In addition, binaural auralizations for selected spaces are provided.

  2. Effects of tissue heterogeneity on single-coil, scanning MIT imaging

    NASA Astrophysics Data System (ADS)

    Feldkamp, J. R.; Quirk, S.

    2016-03-01

    We recently reported on the use of a single induction coil to accomplish imaging of the electrical conductivity in human tissues via magnetic induction tomography (MIT). A key to the method was the development of a mapping equation that quantitatively relates an arbitrary electrical conductivity distribution to ohmic loss in a coil consisting of concentric circular loops in a plane. By making multiple coil loss measurements at a number of locations in the vicinity of the target (scan), this mapping equation can be used to build an algorithm for 3D image construction of electrical conductivity. Important assumptions behind the mathematical formula included uniform relative permittivity throughout all space and continuous variation in conductivity. In this paper, these two assumptions were tested in a series of experiments involving the use of human tissue phantoms created from agarose, doped with sufficient sodium chloride to yield physiological conductivities. Inclusions of doped agarose were scanned both while isolated and also while embedded in a matrix of agarose gel having lowered conductivity - to help evaluate the effects of abrupt permittivity change. The effects of discontinuous conductivity change were simulated by filling 5 cm diameter petri dishes with 1.4% aqueous KCl and placing them in a much larger, 14 cm diameter petri dish - gap distance varied from about 3 mm to 30 mm. In either case, we will show that these effects are minimal on resultant images, helping to further validate the mapping equation used to construct MIT images. Because of their simplicity, scans reported here did not include coil rotation. To acknowledge the importance of rotation, however, we have devoted a section of this work to illustrate the profound benefits of coil rotation during a scan - though virtual data are used, where coil rotation is more easily specified.

  3. Entropy Generation/Availability Energy Loss Analysis Inside MIT Gas Spring and "Two Space" Test Rigs

    NASA Technical Reports Server (NTRS)

    Ebiana, Asuquo B.; Savadekar, Rupesh T.; Patel, Kaushal V.

    2006-01-01

    The results of the entropy generation and availability energy loss analysis under conditions of oscillating pressure and oscillating helium gas flow in two Massachusetts Institute of Technology (MIT) test rigs piston-cylinder and piston-cylinder-heat exchanger are presented. Two solution domains, the gas spring (single-space) in the piston-cylinder test rig and the gas spring + heat exchanger (two-space) in the piston-cylinder-heat exchanger test rig are of interest. Sage and CFD-ACE+ commercial numerical codes are used to obtain 1-D and 2-D computer models, respectively, of each of the two solution domains and to simulate the oscillating gas flow and heat transfer effects in these domains. Second law analysis is used to characterize the entropy generation and availability energy losses inside the two solution domains. Internal and external entropy generation and availability energy loss results predicted by Sage and CFD-ACE+ are compared. Thermodynamic loss analysis of simple systems such as the MIT test rigs are often useful to understand some important features of complex pattern forming processes in more complex systems like the Stirling engine. This study is aimed at improving numerical codes for the prediction of thermodynamic losses via the development of a loss post-processor. The incorporation of loss post-processors in Stirling engine numerical codes will facilitate Stirling engine performance optimization. Loss analysis using entropy-generation rates due to heat and fluid flow is a relatively new technique for assessing component performance. It offers a deep insight into the flow phenomena, allows a more exact calculation of losses than is possible with traditional means involving the application of loss correlations and provides an effective tool for improving component and overall system performance.

  4. The MIT Integrated Global System Model: A facility for Assessing and Communicating Climate Change Uncertainty (Invited)

    NASA Astrophysics Data System (ADS)

    Prinn, R. G.

    2013-12-01

    The world is facing major challenges that create tensions between human development and environmental sustenance. In facing these challenges, computer models are invaluable tools for addressing the need for probabilistic approaches to forecasting. To illustrate this, I use the MIT Integrated Global System Model framework (IGSM; http://globalchange.mit.edu ). The IGSM consists of a set of coupled sub-models of global economic and technological development and resultant emissions, and physical, dynamical and chemical processes in the atmosphere, land, ocean and ecosystems (natural and managed). Some of the sub-models have both complex and simplified versions available, with the choice of which version to use being guided by the questions being addressed. Some sub-models (e.g.urban air pollution) are reduced forms of complex ones created by probabilistic collocation with polynomial chaos bases. Given the significant uncertainties in the model components, it is highly desirable that forecasts be probabilistic. We achieve this by running 400-member ensembles (Latin hypercube sampling) with different choices for key uncertain variables and processes within the human and natural system model components (pdfs of inputs estimated by model-observation comparisons, literature surveys, or expert elicitation). The IGSM has recently been used for probabilistic forecasts of climate, each using 400-member ensembles: one ensemble assumes no explicit climate mitigation policy and others assume increasingly stringent policies involving stabilization of greenhouse gases at various levels. These forecasts indicate clearly that the greatest effect of these policies is to lower the probability of extreme changes. The value of such probability analyses for policy decision-making lies in their ability to compare relative (not just absolute) risks of various policies, which are less affected by the earth system model uncertainties. Given the uncertainties in forecasts, it is also clear that

  5. The MIT IGSM-CAM framework for uncertainty studies in global and regional climate change

    NASA Astrophysics Data System (ADS)

    Monier, E.; Scott, J. R.; Sokolov, A. P.; Forest, C. E.; Schlosser, C. A.

    2011-12-01

    The MIT Integrated Global System Model (IGSM) version 2.3 is an intermediate complexity fully coupled earth system model that allows simulation of critical feedbacks among its various components, including the atmosphere, ocean, land, urban processes and human activities. A fundamental feature of the IGSM2.3 is the ability to modify its climate parameters: climate sensitivity, net aerosol forcing and ocean heat uptake rate. As such, the IGSM2.3 provides an efficient tool for generating probabilistic distribution functions of climate parameters using optimal fingerprint diagnostics. A limitation of the IGSM2.3 is its zonal-mean atmosphere model that does not permit regional climate studies. For this reason, the MIT IGSM2.3 was linked to the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM) version 3 and new modules were developed and implemented in CAM in order to modify its climate sensitivity and net aerosol forcing to match that of the IGSM. The IGSM-CAM provides an efficient and innovative framework to study regional climate change where climate parameters can be modified to span the range of uncertainty and various emissions scenarios can be tested. This paper presents results from the cloud radiative adjustment method used to modify CAM's climate sensitivity. We also show results from 21st century simulations based on two emissions scenarios (a median "business as usual" scenario where no policy is implemented after 2012 and a policy scenario where greenhouse-gas are stabilized at 660 ppm CO2-equivalent concentrations by 2100) and three sets of climate parameters. The three values of climate sensitivity chosen are median and the bounds of the 90% probability interval of the probability distribution obtained by comparing the observed 20th century climate change with simulations by the IGSM with a wide range of climate parameters values. The associated aerosol forcing values were chosen to ensure a good agreement of the simulations

  6. [Evaluation of the Musical Concentration Training with Pepe (MusiKo mit Pepe) for children with attention deficits].

    PubMed

    Rothmann, Kathrin; Hillmer, Jana-Mareike; Hosser, Daniela

    2014-09-01

    Fragestellung: Die vorliegende Studie überprüft die Wirksamkeit des Musikalischen Konzentrationstrainings mit Pepe (MusiKo mit Pepe) für fünf- bis zehnjährige Kinder mit Aufmerksamkeitsproblemen. Methodik: In einem Prä-Post-Kontrollgruppendesign (N = 108) wurden Veränderungen der Aufmerksamkeitsleistung mittels der Testbatterie zur Aufmerksamkeitsprüfung für Kinder (KiTAP) sowie Veränderungen der kindlichen Lebensqualität mittels des Fragebogens für Kinder (KINDL-R) erfasst. Zusätzlich wurden Fremdbeurteilungsbögen zur Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung (FBB-ADHS) sowie zur Störung des Sozialverhaltens (FBB-SSV) des Diagnostik-Systems für psychische Störungen nach ICD-10 und DSM-IV für Kinder und Jugendliche II und der Eltern- und der Lehrerfragebogen über das Verhalten von Kindern und Jugendlichen (CBCL, TRF) eingesetzt. Ergebnisse: Es zeigen sich für die am Training teilnehmenden Kinder im Vergleich zu der Kontrollgruppe über die Zeit signifikante Verbesserungen der Aufmerksamkeitsleistung sowie der Lebensqualität. Darüber hinaus ergibt sich eine signifikante Reduktion der ADHS-Symptomatik im Eltern- und Lehrerurteil sowie eine Verminderung der Internalisierenden Probleme im Elternurteil. Die Behandlungseffektivität ist unabhängig von Alter, Geschlecht, Intelligenz und Migrationshintergrund der teilnehmenden Kinder. Schlussfolgerung: Das musikbasierte Trainingsprogramm MusiKo mit Pepe stellt eine wirkungsvolle Maßnahme zur Behandlung von Aufmerksamkeitsproblemen dar, sollten sich diese Effekte in Replikationsstudien bestätigen.

  7. A Preliminary MIT-VLA Snapshot Survey Catalog: 8000 MG/PMN Sources at 4.8/8.4 GHz and 0.''3 Resolution

    NASA Astrophysics Data System (ADS)

    Fletcher, A. B.; Burke, B. F.; Conner, S. R.; Herold, L. K.; Lehar, J.; Winn, J. N.; Hewitt, J. N.; Langston, G. I.; Lawrence, C. R.; Bennett, C. L.

    1999-09-01

    A preliminary catalog of the 1981-1994 MIT-VLA Snapshot Survey for radio-loud gravitational lenses will be made available via anonymous ftp from MIT in June 1999 (ftp zenobia.mit.edu; cd pub/fletcher; get mitvla.readme). This plain text catalog contains detailed information on the VLA positions, flux densities and morphologies of ~ 6200 northern MIT-Greenbank (MG) and ~ 1800 Parkes-MIT-NRAO (PMN) radio sources at 4.8 and 8.4 GHz, and at angular resolutions ranging from 0.2 to 0.4 arcseconds. These sources represent ~ 80% of the entire 15 year MIT-VLA Snapshot Survey effort from 1981 to 1995, and are complementary to MIT's VLA-Magellan Gravitational Lens Survey of ~ 1900 flat-spectrum sources begun last year (see J. Winn et al., 1998, BAAS 30(4), p.1425, with a paper recently submitted to the ApJS). The 4.8 GHz single-dish flux densities of the ~ 8000 MIT-VLA sources range from ~ 70 mJy to ~ 5000 mJy. Though the sample is incomplete, it is consistently representative of the wide variety of source morphologies and spectral indices appearing in the MIT-VLA Snapshot Survey. This preliminary MIT-VLA catalog will be improved and checked before publication. It is meanwhile intended as a general purpose resource for the astronomical community; possible uses include (1) organizing an optical follow-up of known gravitational lens candidates within the sample (see A. Fletcher, 1998, MIT Ph.D. thesis), (2) assembling samples of new compact MG and PMN radio sources requiring further imaging using VLBI, such as compact doubles and position calibrators, (3) estimating the mean growth rate of the kiloparsec-scale extended structures in radio-loud AGN (see A. Fletcher & B. Burke, 1998, BAAS 30(4), p.1249), and (4) providing sub-arcsecond information missing from overlapping radio sky surveys made at lower angular resolution, such as the FIRST, WENSS, NVSS and Molonglo Wide Field Surveys.

  8. Harvard-MIT research program in short-lived radiopharmaceuticals. Final report

    SciTech Connect

    Adelstein, S.J.

    1995-02-01

    The Harvard-MIT Research Program in Short-lived Radiopharmaceuticals was established in 1977 to foster interaction among groups working in radiopharmaceutical chemistry at Harvard Medical School, the Massachusetts Institute of Technology, and the Massachusetts General Hospital. To this was added a group at The Childrens Hospital. From these collaborations and building upon the special strengths of the participating individuals, laboratories and institutions, it was hoped that original approaches would be found for the design of new, clinically useful, radiolabeled compounds. The original thrust of this proposal included: (a) examination of the coordination chemistry of technetium as a basis for rational radiopharmaceutical design, (b) development of an ultrashort-lived radionuclide generator for the diagnosis of congenital heart disease in newborns, (c) synthesis of receptor-site-directed halopharmaceuticals, (d) improved facile labeling of complex molecules with positron-emitting radionuclides. The authors` 1986 proposal was oriented toward organs and disease, emphasizing radiolabeled agents that delineate specific functions and the distribution of receptors in brain, heart, and tumors. In 1989, they further refined their purposes and focused on two major aims: (a) synthesis and utilization of neutral technetium and rhenium complexes of high specific activity, and (b) development of new approaches to the radiolabeling of proteins, peptides, immunoglobulins, and their fragments. In 1992, the authors amended this proposal to concentrate their efforts on biologically active peptides and proteins for targeted radiodiagnosis and therapy.

  9. NASA Education and Public Outreach Initiatives at the MIT Center for Space Research

    NASA Astrophysics Data System (ADS)

    Porro, I. L.

    2003-12-01

    Since its inception in 1999, the EPO office of the MIT Center for Space Research (CSR) has fostered direct participation of local scientists in educational initiatives such as teachers workshops and public tours of the Chandra Operations and Control Center. The role played by the CSR EPO office has grown significantly, thanks to the award of a number of EPO grants associated with the Chandra and HETE missions. In the past year about one-third of the CSR research staff was involved in the office's EPO initiatives: more than 500 K-12 students, about half from underrepresented groups, were included in formal education programs and informal education events attracted an estimated 900 people. Today the mission of the CSR EPO office is focused in two areas: professional development for K-12 science teachers, and educational programs in out-of-school time. To be associated with major NASA research missions is beneficial to our mission in several respects, but provides also specific challenges. We present here some of the strategies and intiatives that we have undertaken to overcome those challenges.

  10. A Truck, a Plasma and a Pickle: On the Road with MIT's Traveling Plasma Lab

    NASA Astrophysics Data System (ADS)

    Thomas, Paul

    2004-11-01

    For the past 12 years MIT's Mr. Magnet community outreach program has brought the excitement of magnetism into New England's local schools. Averaging 60-70 school visits each year, Mr. Magnet has become a popular school assembly choice. Paul Thomas, the program's creator, has recently expanded the program to offer a one-hour lecture on the principles of plasma science, geared toward middle schools and high schools. The behavior of particles of matter and light in a plasma is complex. Rather than attempt to convey a complete understanding of their quantum nature in a single lecture, Paul Thomas focuses on presenting just enough information to excite a student's imagination. Using a glow discharge plasma, an emission spectrometer, and such ubiquitous substances as nail polish remover, local dirt and a pickle, students discover, by experiment, the unique properties of the plasma state. Equal parts teacher and showman, Paul explains the basic science of plasma while engaging students with hands-on experiments. Paul Thomas will showcase some of his plasma experiments ``live on stage.'' He will explain some of the mechanics involved with traveling to schools, and how he succeeds in engaging students in science exploration. His goal is to spark curiosity, which may lead a student to study science in college or pursue science as a career. He hopes also to encourage APS-DPP members who may wish to establish educational outreach programs for their local communities.

  11. Field Measurement-Based System Identification and Dynamic Response Prediction of a Unique MIT Building.

    PubMed

    Cha, Young-Jin; Trocha, Peter; Büyüköztürk, Oral

    2016-01-01

    Tall buildings are ubiquitous in major cities and house the homes and workplaces of many individuals. However, relatively few studies have been carried out to study the dynamic characteristics of tall buildings based on field measurements. In this paper, the dynamic behavior of the Green Building, a unique 21-story tall structure located on the campus of the Massachusetts Institute of Technology (MIT, Cambridge, MA, USA), was characterized and modeled as a simplified lumped-mass beam model (SLMM), using data from a network of accelerometers. The accelerometer network was used to record structural responses due to ambient vibrations, blast loading, and the October 16th 2012 earthquake near Hollis Center (ME, USA). Spectral and signal coherence analysis of the collected data was used to identify natural frequencies, modes, foundation rocking behavior, and structural asymmetries. A relation between foundation rocking and structural natural frequencies was also found. Natural frequencies and structural acceleration from the field measurements were compared with those predicted by the SLMM which was updated by inverse solving based on advanced multiobjective optimization methods using the measured structural responses and found to have good agreement. PMID:27376303

  12. Field Measurement-Based System Identification and Dynamic Response Prediction of a Unique MIT Building

    PubMed Central

    Cha, Young-Jin; Trocha, Peter; Büyüköztürk, Oral

    2016-01-01

    Tall buildings are ubiquitous in major cities and house the homes and workplaces of many individuals. However, relatively few studies have been carried out to study the dynamic characteristics of tall buildings based on field measurements. In this paper, the dynamic behavior of the Green Building, a unique 21-story tall structure located on the campus of the Massachusetts Institute of Technology (MIT, Cambridge, MA, USA), was characterized and modeled as a simplified lumped-mass beam model (SLMM), using data from a network of accelerometers. The accelerometer network was used to record structural responses due to ambient vibrations, blast loading, and the October 16th 2012 earthquake near Hollis Center (ME, USA). Spectral and signal coherence analysis of the collected data was used to identify natural frequencies, modes, foundation rocking behavior, and structural asymmetries. A relation between foundation rocking and structural natural frequencies was also found. Natural frequencies and structural acceleration from the field measurements were compared with those predicted by the SLMM which was updated by inverse solving based on advanced multiobjective optimization methods using the measured structural responses and found to have good agreement. PMID:27376303

  13. Development of Improved Models, Stochasticity, and Frameworks for the MIT Extensible Air Network Simulation

    NASA Technical Reports Server (NTRS)

    Clarke, John-Paul

    2004-01-01

    MEANS, the MIT Extensible Air Network Simulation, was created in February of 2001, and has been developed with support from NASA Ames since August of 2001. MEANS is a simulation tool which is designed to maximize fidelity without requiring data of such a low level as to preclude easy examination of alternative scenarios. To this end, MEANS is structured in a modular fashion to allow more detailed components to be brought in when desired, and left out when they would only be an impediment. Traditionally, one of the difficulties with high-fidelity models is that they require a level of detail in their data that is difficult to obtain. For analysis of past scenarios, the required data may not have been collected, or may be considered proprietary and thus difficult for independent researchers to obtain. For hypothetical scenarios, generation of the data is sufficiently difficult to be a task in and of itself. Often, simulations designed by a researcher will model exactly one element of the problem well and in detail, while assuming away other parts of the problem which are not of interest or for which data is not available. While these models are useful for working with the task at hand, they are very often not applicable to future problems. The MEAN Simulation attempts to address these problems by using a modular design which provides components of varying fidelity for each aspect of the simulation. This allows for the most accurate model for which data is available to be used. It also provides for easy analysis of sensitivity to data accuracy. This can be particularly useful in the case where accurate data is available for some subset of the situations that are to be considered. Furthermore, the ability to use the same model while examining effects on different parts of a system reduces the time spent learning the simulation, and provides for easier comparisons between changes to different parts of the system.

  14. Autolytic activity of human calpain 7 is enhanced by ESCRT-III-related protein IST1 through MIT-MIM interaction.

    PubMed

    Osako, Yohei; Maemoto, Yuki; Tanaka, Ryohei; Suzuki, Hironori; Shibata, Hideki; Maki, Masatoshi

    2010-11-01

    Calpain 7, a mammalian ortholog of yeast Cpl1/Rim13 and fungal PalB, is an atypical calpain that lacks a penta-EF-hand domain. Previously, we reported that a region containing a tandem repeat of microtubule-interacting and transport (MIT) domains in calpain 7 interacts with a subset of endosomal sorting complex required for transport (ESCRT)-III-related proteins, suggesting involvement of calpain 7 in the ESCRT system. Although yeast and fungal calpains are thought to be involved in alkaline adaptation via limited proteolysis of specific transcription factors, proteolytic activity of calpain 7 has not been demonstrated yet. In this study, we investigated the interaction between calpain 7 and a newly reported ESCRT-III family member, increased sodium tolerance-1 (IST1), which possesses two different types of MIT-interacting motifs (MIM1 and MIM2). We found that glutathione-S-transferase (GST)-fused tandem MIT domains of calpain 7 (calpain 7MIT) pulled down FLAG-tagged IST1 expressed in HEK293T cells. Coimmunoprecipitation assays with various deletion or point mutants of epitope-tagged calpain 7 and IST1 revealed that both repetitive MIT domains and MIMs are required for efficient interaction. Direct MIT-MIM binding was confirmed by a pulldown experiment with GST-fused IST1 MIM and purified recombinant calpain 7MIT. Furthermore, we found that the GST-MIM protein enhances the autolysis of purified Strep-tagged monomeric green fluorescent protein (mGFP)-fused calpain 7 (mGFP-calpain 7-Strep). The autolysis was almost completely abolished by 10 mmN-ethylmaleimide but only partially inhibited by 1 mm leupeptin or E-64. The putative catalytic Cys290-substituted mutant (mGFP-calpain 7(C290S)-Strep) showed no autolytic activity. These results demonstrate for the first time that human calpain 7 is proteolytically active, and imply that calpain 7 is activated in the ESCRT system. PMID:20849418

  15. The MitCHAP-60 disease is due to entropic destabilization of the human mitochondrial Hsp60 oligomer.

    PubMed

    Parnas, Avital; Nadler, Michal; Nisemblat, Shahar; Horovitz, Amnon; Mandel, Hanna; Azem, Abdussalam

    2009-10-01

    The 60-kDa heat shock protein (mHsp60) is a vital cellular complex that mediates the folding of many of the mitochondrial proteins. Its function is executed in cooperation with the co-chaperonin, mHsp10, and requires ATP. Recently, the discovery of a new mHsp60-associated neurodegenerative disorder, MitCHAP-60 disease, has been reported. The disease is caused by a point mutation at position 3 (D3G) of the mature mitochondrial Hsp60 protein, which renders it unable to complement the deletion of the homologous bacterial protein in Escherichia coli (Magen, D., Georgopoulos, C., Bross, P., Ang, D., Segev, Y., Goldsher, D., Nemirovski, A., Shahar, E., Ravid, S., Luder, A., Heno, B., Gershoni-Baruch, R., Skorecki, K., and Mandel, H. (2008) Am. J. Hum. Genet. 83, 30-42). The molecular basis of the MitCHAP-60 disease is still unknown. In this study, we present an in vitro structural and functional analysis of the purified wild-type human mHsp60 and the MitCHAP-60 mutant. We show that the D3G mutation leads to destabilization of the mHsp60 oligomer and causes its disassembly at low protein concentrations. We also show that the mutant protein has impaired protein folding and ATPase activities. An additional mutant that lacks the first three amino acids (N-del), including Asp-3, is similarly impaired in refolding activity. Surprisingly, however, this mutant exhibits profound stabilization of its oligomeric structure. These results suggest that the D3G mutation leads to entropic destabilization of the mHsp60 oligomer, which severely impairs its chaperone function, thereby causing the disease.

  16. Measuring Neutron Spectrum at MIT Research Reactor Utilizing He-3 Bonner Cylinder Approach with an Unfolding Analysis

    NASA Astrophysics Data System (ADS)

    Leder, Alexander; Ricochet Collaboration

    2016-03-01

    The Ricochet experiment seeks to measure Coherent (neutral-current) Elastic Neutrino-Nucleus Scattering (CENNS) using dark matter style detectors placed near a neutrino source, possibly the MIT research reactor (MITR), which offers a high continuous neutrino flux at high energies. Currently, Ricochet is characterizing the backgrounds at MITR. The main background is the neutrons emitted simultaneously from the core. To characterize this background, we wrapped a Bonner cylinder around a 3He thermal neutron detector, whose data was then unfolded to produce a neutron energy spectrum across several orders of magnitude. We discuss the resulting spectrum as well its implications for deploying Ricochet in the future.

  17. Comparative costs of the Mouse Inoculation Test (MIT) and Virus Isolation in Cell Culture (VICC) for use in rabies diagnosis in Brazil.

    PubMed

    Bones, Vanessa C; Gameiro, Augusto H; Castilho, Juliana G; Molento, Carla F M

    2015-05-01

    The decision to use laboratory animals rather than in vitro methods is frequently based on the financial costs involved, so the objective of our study was to compare the costs of performing the Mouse Inoculation Test (MIT) and Virus Isolation in Cell Culture (VICC) for use in rabies diagnosis in Brazil. Based on observations of laboratory routines at the Pasteur Institute, São Paulo, we listed the fixed cost (FC) and variable cost (VC) items necessary to perform both tests. Considering that 200 MITs are equivalent to 350 VICC assays, in terms of facilities and staff-hours needed per month, we calculated, for both tests, the average total cost per sample, the costs of the implementation of the laboratory structure, and the costs of routine use. With regard to absolute values, the total cost was mainly influenced by FC items, as they represented 60% of the cost for the MIT and 86% of the cost for VICC. A sample analysed by the MIT costs around 205% more than one analysed by using VICC. The MIT costs 74% and 406% more than VICC, when implementation costs and routine use per month, respectively, are taken into account. Our results can assist in the resolution of costing disputes that could hinder the replacement of animals for rabies diagnosis in Brazil. The method demonstrated here might also be useful for cost comparisons in other situations where animal use still continues when validated alternatives exist.

  18. First results from the ‘Violin-Mode’ tests on an advanced LIGO suspension at MIT

    NASA Astrophysics Data System (ADS)

    Lockerbie, N. A.; Carbone, L.; Shapiro, B.; Tokmakov, K. V.; Bell, A.; Strain, K. A.

    2011-12-01

    This paper describes the first results from ‘Violin-Mode’ measurements made on the four suspension fibres of a fully suspended 40 kg test mass. These measurements were made at the LIGO lab, Gravitational Wave Observatory test facility, at MIT. Here, an aluminium-alloy (dummy) test mass, simulating an advanced LIGO (Laser Interferometer Gravitational Wave Observatory) test mass/mirror, had been suspended in air from a test suspension by four fused-silica suspension fibres, each measuring 400 µm in diameter × 600 mm long. Violin-Mode measurements were made on these highly tensioned fibres by retrofitting a prototype system of four novel shadow sensors to the test suspension, one per fibre, these sensors having, collectively, a displacement sensitivity of (6.9 ± 1.3) × 10-11 m (rms) Hz-1/2, at 500 Hz, over a measuring span of ±0.1 mm. Violin-Mode fundamental resonances were detected in all four fibres: with frequencies ˜ 485 Hz when the test mass was supported lightly from below, and at ˜500 Hz when it was fully suspended. In the latter case the Violin-Mode detection took place whilst the test mass, together with its suspension fibres, was undergoing relatively large-amplitude ‘pendulum-mode’ motion, at ˜0.6 Hz. This motion was measured to have a peak-peak amplitude at one of the suspension fibres of up to ˜140 µm (35 µm, rms)—the shadow sensors each having subsidiary outputs for monitoring such low-frequency, large amplitude, motion. Under fully suspended conditions, a calibrated Violin-Mode ‘free-oscillation’ amplitude of 430 ± 20 picometres, rms, was measured at 500.875 Hz, in the same suspension fibre which was found to be undergoing, simultaneously, the ˜140 µm peak-peak motion. Over the bandwidth monitored (dc to 3.2 kHz), Violin-Mode harmonics up to the sixth were recorded in an evoked response. It was concluded that the prototype system had demonstrated amply its practical viability as a detector of Violin-Mode resonances in the

  19. The Ashima/MIT Mars GCM and argon in the martian atmosphere

    NASA Astrophysics Data System (ADS)

    Lian, Yuan; Richardson, Mark I.; Newman, Claire E.; Lee, Christopher; Toigo, Anthony D.; Mischna, Michael A.; Campin, Jean-Michel

    2012-04-01

    We investigate the ability of modern general circulation models (GCMs) to simulate transport in the martian atmosphere using measurements of argon as a proxy for the transport processes. Argon provides the simplest measure of transport as it is a noble gas with no sinks or sources on seasonal timescales. Variations in argon result solely from 'freeze distillation', as the atmosphere condenses at the winter poles, and from atmospheric transport. Comparison of all previously published models when rescaled to a common definition of the argon enhancement factor (EF) suggest that models generally do a poor job in predicting the peak enhancement in southern winter over the winter pole - the time when the capability of the model transport approaches are most severely tested. Despite observed peak EF values of ˜6, previously published model predictions peaked at EF values of only 2-3. We introduce a new GCM that provides a better treatment of mass conservation within the dynamical core, includes more sophisticated tracer transport approaches, and utilizes a cube-sphere grid structure thus avoiding the grid-point convergence problem at the pole that exists for most current Mars GCMs. We describe this model - the Ashima Research/Massachusetts Institute of Technology Mars General Circulation Model (Ashima/MIT Mars GCM) and use it to demonstrate the significant sensitivity of peak EF to the choices of transport approach for both tracers and heat. We obtain a peak EF of 4.75 which, while over 50% higher than any prior model, remains well short of the observed value. We show that the polar EF value in winter is primarily determined by the competition between two processes: (1) mean meridional import of lower-latitude air not enriched in argon and (2) the leakage of enriched argon out of the polar column by eddies in the lowest atmospheric levels. We suggest possibilities for improving GCM representation of the CO2 cycle and the general circulation that may further improve the

  20. Mit castor satellite: Design, implementation, and testing of the communication system

    NASA Astrophysics Data System (ADS)

    Babuscia, Alessandra; McCormack, Matthew Michael; Munoz, Michael; Parra, Spencer; Miller, David W.

    2012-12-01

    Cathode Anode Satellite Thruster for Orbital Reposition (CASTOR) is an orbital manoeuvre and transfer micro-satellite bus developed at MIT Space System Laboratory. The technical objective of the mission is achieving 1 km/s of delta-V over a 1 year mission in Low Earth Orbit (LEO). This will be accomplished using a novel electric propulsion system, the Diverging Cusped Field Thruster (DCFT), which enables high efficiency orbital changes of the ESPA-ring class satellite. CASTOR is capable of improving rapid access to space capabilities by providing an orbital transfer platform with a very high performance to mass ratio, thus greatly reducing launch costs and allowing for highly efficient orbital manoeuvre. Furthermore, CASTOR is highly scalable and modular, allowing it to be adapted to a wide range of scales and applications. CASTOR is developed as part of the University Nanosatellite Program (UNP) funded by Air Force Research Laboratory (AFRL). In order to accomplish CASTOR mission objective, a highly optimized, scalable, light weight, and low cost communication system needed to be developed. These constraints imply the development of trade studies to select the final communication system architecture able to maximize the amount of data transmitted, while guaranteeing reliability, redundancy and limited mass, power consumption, and cost. A special attention is also required to guarantee a reliable communication system in cases of tumbling, or in case of strong Doppler shift which is inevitable due to the high delta-V capabilities of the vehicle. In order to accomplish all the mission requirements, different features have been introduced in the design of the communication system for this mission. Specifically, customized patch antennas have been realized, and a customized communication protocol has been designed and implemented. The communication subsystem has been validated through an intense testing campaign which included software tests in the laboratory, hardware

  1. Sustainable materials

    NASA Astrophysics Data System (ADS)

    Allwood, Julian M.

    2016-01-01

    Materials influence every aspect of the energy system; therefore, as well as developing new materials for energy generation, materials scientists should engage in public debate about the limitations of future innovations and the conservation of existing materials.

  2. The MIT HEDP Accelerator Facility for education and advanced diagnostics development for OMEGA, Z and the NIF

    NASA Astrophysics Data System (ADS)

    Petrasso, R.; Gatu Johnson, M.; Armstrong, E.; Han, H. W.; Kabadi, N.; Lahmann, B.; Orozco, D.; Rojas Herrera, J.; Sio, H.; Sutcliffe, G.; Frenje, J.; Li, C. K.; Séguin, F. H.; Leeper, R.; Ruiz, C. L.; Sangster, T. C.

    2015-11-01

    The MIT HEDP Accelerator Facility utilizes a 135-keV linear electrostatic ion accelerator, a D-T neutron source and two x-ray sources for development and characterization of nuclear diagnostics for OMEGA, Z, and the NIF. The ion accelerator generates D-D and D-3He fusion products through acceleration of D ions onto a 3He-doped Erbium-Deuteride target. Fusion reaction rates around 106 s-1 are routinely achieved, and fluence and energy of the fusion products have been accurately characterized. The D-T neutron source generates up to 6 × 108 neutrons/s. The two x-ray generators produce spectra with peak energies of 35 keV and 225 keV and maximum dose rates of 0.5 Gy/min and 12 Gy/min, respectively. Diagnostics developed and calibrated at this facility include CR-39 based charged-particle spectrometers, neutron detectors, and the particle Time-Of-Flight (pTOF) and Magnetic PTOF CVD-diamond-based bang time detectors. The accelerator is also a vital tool in the education of graduate and undergraduate students at MIT. This work was supported in part by SNL, DOE, LLE and LLNL.

  3. MIT jar test of the natural polymer chitosan with fresh pond water from the Cambridge Water Department, November-December 1992

    SciTech Connect

    Murcott, S.; Harleman, D.R.F.

    1993-01-01

    The purpose of the MIT (Massachusetts Institute of Technology) jar tests of chitosan using CWD (Cambridge Water Department Treatment Plant) water was to demonstrate the effectiveness of chitosan as a coagulant in drinking water applications. The approach was to compare the performance of the natural organic coagulant, chitosan, to the performance of alum and other chemical coagulants in terms of the parameters turbidity, color, pH and alkalinity. Twenty-five jar tests were conducted during November and December, 1992, at Parsons Laboratory, MIT, Cambridge, Massachusetts.

  4. The Effect of Multiple Intelligences Theory (MIT)-based Instruction on Attitudes towards the Course, Academic Success, and Permanence of Teaching on the Topic of "Respiratory Systems"

    ERIC Educational Resources Information Center

    Koksal, Mustafa Serdar; Yel, Mustafa

    2007-01-01

    Studies on the effective teaching of biology have been continuously increasing since the 1800s. New teaching approaches have been purposed and tried out along the way. The multiple intelligences theory (MIT)-based approaches which give more importance to individual in educational settings can provide alternatives for meeting this requirement. An…

  5. Enhancing undergraduate education in aerospace engineering and planetary sciences at MIT through the development of a CubeSat mission

    NASA Astrophysics Data System (ADS)

    Smith, Matthew W.; Miller, David W.; Seager, Sara

    2011-09-01

    CubeSats are a class of nanosatellites that conform to a standardized 10 cm x 10 cm x 10 cm, 1 kg form factor. This miniaturization, along with a standardized deployment device for launch vehicles, allows CubeSats to be launched at low cost by sharing the trip to orbit with other spacecraft. Part of the original motivation for the CubeSat platform was also to allow university students to participate more easily in space technology development and to gain hands-on experience with flight hardware. The Department of Aeronautics and Astronautics along with the Department of Earth, Atmospheric, and Planetary Studies (EAPS) at the Massachusetts Institute of Technology (MIT) recently completed a three semester-long course that uses the development of a CubeSat-based science mission as its core teaching method. Serving as the capstone academic experience for undergraduates, the goal of this class is to design and build a CubeSat spacecraft that serves a relevant science function, such as the detection of exoplanets transiting nearby stars. This project-based approach gives students essential first hand insights into the challenges of balancing science requirements and engineering design. Students are organized into subsystem-specific teams that refine and negotiate requirements, explore the design trade space, perform modeling and simulation, manage interfaces, test subsystems, and finally integrate prototypes and flight hardware. In this work we outline the heritage of capstone design/build classes at MIT, describe the class format in greater detail, and give results on the ability to meet learning objectives using this pedagogical approach.

  6. Weird materials

    NASA Astrophysics Data System (ADS)

    Astin, Christina; Talbot, Diane; Goodhew, Peter

    2002-11-01

    Heat a material and it gets hotter; heat it enough and it will melt. But some materials will behave rather unexpectedly when heated, and others can act strangely when deformed. Here, three types of weird materials are described - shape memory alloys, Silly Putty® and thermochromic materials - and examples are given of their uses in manufacturing and in the classroom.

  7. Understanding Materials

    ERIC Educational Resources Information Center

    Katsioloudis, Petros J.

    2010-01-01

    Almost everything people have ever done has involved materials. Historical evidence indicates that "engineered materials" have been available and utilized for the benefit of humankind since the Neolithic period, beginning about 10,000 BC. Some of these materials have been in existence for thousands of years. At first, materials consisted of wood,…

  8. The MIT/WHOI Joint Program in Oceanography and Applied Ocean Science and Engineering: An Ongoing Experiment in Graduate Education and the Sverdrup, Johnson and Fleming Influence.

    NASA Astrophysics Data System (ADS)

    Farrington, J. W.

    2002-12-01

    On May 8, 1968 Paul M. Fye, President of Woods Hole Oceanographic Institution and Howard W. Johnson, President of Massachusetts Institute of Oceanography, signed a Memorandum of Agreement of one and one-half pages in which both partner institutions "have each approved the creation of a Joint Graduate Program in Oceanography for which there will be established appropriate graduate degrees to be conferred jointly by the Massachusetts Institute of Technology and Woods Hole Oceanographic Institution." The partnership brought together the MIT experience with formal graduate education in sciences and engineering involving classroom instruction and more traditional academic advising with the less formal one to one "apprenticeship" or European tutorial style of education at WHOI. During the first year the graduate program involved only the physical sciences with the MIT home being in the Earth, Atmospheric and Planetary Sciences Department. Ocean Engineering was added the following year with the MIT home being the Ocean Engineering Department. Biological Oceanography was added in 1970 with the MIT home being the Biology Department. The existing graduate curricula of the home departments at MIT, the inclusion of ocean engineering, and the fact that several of the early program instructors and advisers at WHOI entered oceanography after formal graduate training in more traditional disciplines such as chemistry, geology, physics, biology and mathematics was not conducive to an automatic adoption of the Sverdrup, Johnson and Fleming paradigm of core courses that predominated in other leading graduate programs in oceanography. Despite this caveat, the Sverdrup, Johnson and Fleming paradigm has influenced the learning environment in the Joint Program. Taking into account lessons learned in the process, some suggestions for the future of graduate education in ocean sciences and ocean engineering will be presented.

  9. MIT-EAPS Neutron Activation Analysis and Radiometric Laboratory Contribution to Geosciences: Past, Present, and Future

    SciTech Connect

    Pillalamarri, Ila

    2005-09-08

    The Instrumental Neutron Activation Analysis (INAA) and Radiometric Laboratory's current system is described. This laboratory has been in continuous operation for the past thirty years. A review is provided about the laboratory's analytical participation in trace element geochemical studies of the earth's upper mantle, trace impurity studies of high purity materials, the provenance study of archaeological glass beads, trace multi-element analyses of standard reference materials, the preparation of synthetic analytical standards for Neutron Activation Analysis, and providing a training course in nuclear analytical techniques for environmental samples. The multi-element analysis by INAA consists of determining elements like the rare earths La, Ce, Nd, Sm Eu, Tb, Dy, Ho, Yb, Lu, and also As, Ba, Cl, Co, Cr, Cs, Dy, Fe, Hf, Hg, K, Mn, Na, Ta, Th, U. The projected future of the laboratory is explained in terms of its resources, expertise in high precision analysis of trace impurities for the material selection that is to be used in rare event physics experiments. For example, this 'surface' laboratory can be efficiently interfaced/integrated with a deep underground low background counting facility, especially in the initial stages.

  10. Metal-Insulator Transition Driven by Vacancy Ordering in GeSbTe Phase Change Materials.

    PubMed

    Bragaglia, Valeria; Arciprete, Fabrizio; Zhang, Wei; Mio, Antonio Massimiliano; Zallo, Eugenio; Perumal, Karthick; Giussani, Alessandro; Cecchi, Stefano; Boschker, Jos Emiel; Riechert, Henning; Privitera, Stefania; Rimini, Emanuele; Mazzarello, Riccardo; Calarco, Raffaella

    2016-01-01

    Phase Change Materials (PCMs) are unique compounds employed in non-volatile random access memory thanks to the rapid and reversible transformation between the amorphous and crystalline state that display large differences in electrical and optical properties. In addition to the amorphous-to-crystalline transition, experimental results on polycrystalline GeSbTe alloys (GST) films evidenced a Metal-Insulator Transition (MIT) attributed to disorder in the crystalline phase. Here we report on a fundamental advance in the fabrication of GST with out-of-plane stacking of ordered vacancy layers by means of three distinct methods: Molecular Beam Epitaxy, thermal annealing and application of femtosecond laser pulses. We assess the degree of vacancy ordering and explicitly correlate it with the MIT. We further tune the ordering in a controlled fashion attaining a large range of resistivity. Employing ordered GST might allow the realization of cells with larger programming windows.

  11. Metal - Insulator Transition Driven by Vacancy Ordering in GeSbTe Phase Change Materials

    PubMed Central

    Bragaglia, Valeria; Arciprete, Fabrizio; Zhang, Wei; Mio, Antonio Massimiliano; Zallo, Eugenio; Perumal, Karthick; Giussani, Alessandro; Cecchi, Stefano; Boschker, Jos Emiel; Riechert, Henning; Privitera, Stefania; Rimini, Emanuele; Mazzarello, Riccardo; Calarco, Raffaella

    2016-01-01

    Phase Change Materials (PCMs) are unique compounds employed in non-volatile random access memory thanks to the rapid and reversible transformation between the amorphous and crystalline state that display large differences in electrical and optical properties. In addition to the amorphous-to-crystalline transition, experimental results on polycrystalline GeSbTe alloys (GST) films evidenced a Metal-Insulator Transition (MIT) attributed to disorder in the crystalline phase. Here we report on a fundamental advance in the fabrication of GST with out-of-plane stacking of ordered vacancy layers by means of three distinct methods: Molecular Beam Epitaxy, thermal annealing and application of femtosecond laser pulses. We assess the degree of vacancy ordering and explicitly correlate it with the MIT. We further tune the ordering in a controlled fashion attaining a large range of resistivity. Employing ordered GST might allow the realization of cells with larger programming windows. PMID:27033314

  12. Metal - Insulator Transition Driven by Vacancy Ordering in GeSbTe Phase Change Materials

    NASA Astrophysics Data System (ADS)

    Bragaglia, Valeria; Arciprete, Fabrizio; Zhang, Wei; Mio, Antonio Massimiliano; Zallo, Eugenio; Perumal, Karthick; Giussani, Alessandro; Cecchi, Stefano; Boschker, Jos Emiel; Riechert, Henning; Privitera, Stefania; Rimini, Emanuele; Mazzarello, Riccardo; Calarco, Raffaella

    2016-04-01

    Phase Change Materials (PCMs) are unique compounds employed in non-volatile random access memory thanks to the rapid and reversible transformation between the amorphous and crystalline state that display large differences in electrical and optical properties. In addition to the amorphous-to-crystalline transition, experimental results on polycrystalline GeSbTe alloys (GST) films evidenced a Metal-Insulator Transition (MIT) attributed to disorder in the crystalline phase. Here we report on a fundamental advance in the fabrication of GST with out-of-plane stacking of ordered vacancy layers by means of three distinct methods: Molecular Beam Epitaxy, thermal annealing and application of femtosecond laser pulses. We assess the degree of vacancy ordering and explicitly correlate it with the MIT. We further tune the ordering in a controlled fashion attaining a large range of resistivity. Employing ordered GST might allow the realization of cells with larger programming windows.

  13. Material selection

    SciTech Connect

    Tucker, W.G.

    1990-08-01

    The paper summarizes various criteria that can be used in selecting material used in the construction, furnishing, maintenance, and operation of a building. It also summarizes the types of material and product testing that can be especially useful in the selection process. In broad terms, materials in buildings are classified as building materials, furnishings, maintenance materials, and other contents. At any given time, emissions from materials and products in any of these four categories can dominate the impact on indoor air quality (IAQ) in a building. Responsibility for the selection of these materials may be that of the designer, owner, or occupants. Information on IAQ impacts of materials therefore needs to be developed for a wide range of people.

  14. Hazardous materials

    MedlinePlus

    ... people how to work with hazardous materials and waste. There are many different kinds of hazardous materials, including: Chemicals, like some that are used for cleaning Drugs, like chemotherapy to treat cancer Radioactive material that is used for x-rays or ...

  15. Das heissschlagverdichten — ein neues verfahren zur herstellung keramischer brennstofftabletten mit engen formtoleranzen

    NASA Astrophysics Data System (ADS)

    Hrovat, M.; Mühling, G.; Rachor, L.; Vollath, D.; Zimmermann, H.

    1984-05-01

    The hot impact densification (HID) is a new powerful method for producing ceramic fuel pellets for nuclear reactors. Green ceramic bodies are directly processed to pellets by high speed shaping in the plastic temperature region of ceramic material. Opposed to the well established press sintering procedure it can be heated, densified, and cooled by orders of magnitude faster. Therefore, at high throughputs, small equipment dimensions become possible. The fuel pellets produced meet all requirements, particular the dimensional tolerances achieved are very closed, consequently circular grinding is omitted. Furthermore, the relatively high temperature level of the impact pressing favors the mixed crystal formation of uranium and plutonium oxide. This improves the solubility of the fuel in nitric acid, an essential point at reprocessing. A prototype facility is designed so that automatic fabrication in continuous operation will be possible. The target working cycle for a fuel pellet is in the range of some seconds.

  16. Sub-micrometer aerosol particles in the upper troposphere/lowermost stratosphere as measured by CARIBIC and modeled using the MIT-CAM3 global climate model

    NASA Astrophysics Data System (ADS)

    Ekman, Annica M. L.; Hermann, Markus; Groß, Peter; Heintzenberg, Jost; Kim, Dongchul; Wang, Chien

    2012-06-01

    In this study, we compare modeled (MIT-CAM3) and observed (CARIBIC) sub-micrometer nucleation (N4-12, 4 ≤ d ≤ 12 nm) and Aitken mode (N12, d > 12 nm) particle number concentrations in the upper troposphere and lowermost stratosphere (UT/LMS). Modeled and observed global median N4-12 and N12 agree fairly well (within a factor of two) indicating that the relatively simplified binary H2SO4-H2O nucleation parameterization applied in the model produces reasonable results in the UT/LMS. However, a comparison of the spatiotemporal distribution of sub-micrometer particles displays a number of discrepancies between MIT-CAM3 and CARIBIC data: N4-12is underestimated by the model in the tropics and overestimated in the extra-topics. N12 is in general overestimated by the model, in particular in the tropics and during summer months. The modeled seasonal variability of N4-12 is in poor agreement with CARIBIC data whereas it agrees rather well for N12. Modeled particle frequency distributions are in general narrower than the observed ones. The model biases indicate an insufficient diffusive mixing in MIT-CAM3 and a too large vertical transport of carbonaceous aerosols. The overestimated transport is most likely caused by the constant supersaturation threshold applied in the model for the activation of particles into cloud droplets. The annually constant SO2 emissions in the model may also partly explain the poor representation of the N4-12seasonal cycle. Comparing the MIT-CAM3 with CARIBIC data, it is also clear that care has to be taken regarding the representativeness of the measurement data and the time frequency of the model output.

  17. Early results from the MIT millimeter and sub-millimeter balloon-borne anisotropy measurement. [of cosmic microwave background radiation

    NASA Technical Reports Server (NTRS)

    Meyer, Stephan S.; Cheng, Edward S.; Page, Lyman A.

    1991-01-01

    The MIT balloon-borne bolometric search for Cosmic Microwave Background Radiation (CMBR) anisotropies places the most stringent constraints to date on fluctuations in the CMBR. Four maps of half of the Northern Hemisphere at 1.8, 1.1, 0.63 and 0.44 mm wavelength, have a beam size of 3.8 deg with a 1 sigma sensitivity of less than 0.1 mK (thermodynamic) per FOV in each of the first two channels. Analysis of the sky map at 1.8 mm wavelength using a likelihood ratio test for galactic latitudes of 15 deg and greater yields a 95 percent confidence level (CL) upper limit on fluctuations of the CMBR at DeltaT/T less than or equal to 1.6 x 10 exp -5 with a statistical power of 92 percent for Gaussian fluctuations at a correlation angle of 13 deg. Between 3 deg and 22 deg, the upper limit for fluctuations is DeltaT/T less than or equal to 4.0 x 10 exp -5 (95 percent CL).

  18. VizieR Online Data Catalog: The MIT-Green Bank 5GHz Survey (Bennett+, 1986-91)

    NASA Astrophysics Data System (ADS)

    Bennett, C. L.; Lawrence, C. R.; Burke, B. F.; Hewitt, J. N.; Mahoney, J.

    1999-04-01

    The MIT-Green Bank 5 GHz survey catalog was produced from four separate surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope (Bennett et al., 1986ApJS...61....1B (MG1); Langston et al., 1990ApJS...72..621L (MG2); Griffith et al., 1990ApJS...74..129G (MG3); Griffith et al. 1991ApJS...75..801G (MG4)). The sky coverage of the various surveys is: 00h < RAB < 24h, -00d30'13" < DECB < +19d29'47" for MG1; 04h < RAJ < 21h, +17.0d < DECJ < +39d09' for MG2; 16h30m < RAB < 05h, +17d < DECB < +39d09' for MG3; and 15h30m < RAB < 02h30m, +37.00d < DECB < +50d58'48" for MG4; where RAB and DECB refer to B1950 coordinates, and RAJ and DECJ refer to J2000 coordinates. The catalog contains 20344 sources detected with a signal-to-noise ratio greater than 5 and 3836 possible detections (MG1) with a signal-to-noise ratio less than 5. Spectral indices are computed for MG1 sources also identified in the Texas 365 MHz survey (Douglas et al. 1980), and for MG1-MG4 sources also identified in the NRAO 1400 MHz Survey (Condon and Broderick 1985). (1 data file).

  19. VizieR Online Data Catalog: The MIT-Green Bank 5GHz Survey (Bennett+, 1986-91)

    NASA Astrophysics Data System (ADS)

    Bennett, C. L.; Lawrence, C. R.; Burke, B. F.; Hewitt, J. N.; Mahoney, J.

    2003-08-01

    The MIT-Green Bank 5GHz survey catalog was produced from four separate surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope (Bennett et al., 1986ApJS...61....1B (MG1); Langston et al., 1990ApJS...72..621L (MG2); Griffith et al., 1990ApJS...74..129G (MG3); Griffith et al. 1991ApJS...75..801G (MG4)). The sky coverage of the various surveys is: 00h < RAB < 24h, -00d30'13" < DECB < +19d29'47" for MG1; 04h < RAJ < 21h, +17.0d < DECJ < +39d09' for MG2; 16h30m < RAB < 05h, +17d < DECB < +39d09' for MG3; and 15h30m < RAB < 02h30m, +37.00d < DECB < +50d58'48" for MG4; where RAB and DECB refer to B1950 coordinates, and RAJ and DECJ refer to J2000 coordinates. The catalog contains 20344 sources detected with a signal-to-noise ratio greater than 5 and 3836 possible detections (MG1) with a signal-to-noise ratio less than 5. Spectral indices are computed for MG1 sources also identified in the Texas 365MHz survey (Douglas et al. 1980), and for MG1-MG4 sources also identified in the NRAO 1400MHz Survey (Condon and Broderick 1985). (1 data file).

  20. Upgrade of the MIT Linear Electrostatic Ion Accelerator (LEIA) for nuclear diagnostics development for Omega, Z and the NIF.

    PubMed

    Sinenian, N; Manuel, M J-E; Zylstra, A B; Rosenberg, M; Waugh, C J; Rinderknecht, H G; Casey, D T; Sio, H; Ruszczynski, J K; Zhou, L; Gatu Johnson, M; Frenje, J A; Séguin, F H; Li, C K; Petrasso, R D; Ruiz, C L; Leeper, R J

    2012-04-01

    The MIT Linear Electrostatic Ion Accelerator (LEIA) generates DD and D(3)He fusion products for the development of nuclear diagnostics for Omega, Z, and the National Ignition Facility (NIF). Significant improvements to the system in recent years are presented. Fusion reaction rates, as high as 10(7) s(-1) and 10(6) s(-1) for DD and D(3)He, respectively, are now well regulated with a new ion source and electronic gas control system. Charged fusion products are more accurately characterized, which allows for better calibration of existing nuclear diagnostics. In addition, in situ measurements of the on-target beam profile, made with a CCD camera, are used to determine the metrology of the fusion-product source for particle-counting applications. Finally, neutron diagnostics development has been facilitated by detailed Monte Carlo N-Particle Transport (MCNP) modeling of neutrons in the accelerator target chamber, which is used to correct for scattering within the system. These recent improvements have resulted in a versatile platform, which continues to support the existing nuclear diagnostics while simultaneously facilitating the development of new diagnostics in aid of the National Ignition Campaign at the National Ignition Facility.

  1. Effect of Adding a Regenerator to Kornhauser's MIT "Two-Space" (Gas-Spring+Heat Exchanger) Test Rig

    NASA Technical Reports Server (NTRS)

    Ebiana, Asuquo B.; Gidugu, Praveen

    2008-01-01

    This study employed entropy-based second law post-processing analysis to characterize the various thermodynamic losses inside a 3-space solution domain (gas spring+heat exchanger+regenerator) operating under conditions of oscillating pressure and oscillating flow. The 3- space solution domain is adapted from the 2-space solution domain (gas spring+heat exchanger) in Kornhauser's MIT test rig by modifying the heat exchanger space to include a porous regenerator system. A thermal nonequilibrium model which assumes that the regenerator porous matrix and gas average temperatures can differ by several degrees at a given axial location and time during the cycle is employed. An important and primary objective of this study is the development and application of a thermodynamic loss post-processor to characterize the major thermodynamic losses inside the 3-space model. It is anticipated that the experience gained from thermodynamic loss analysis of the simple 3-space model can be extrapolated to more complex systems like the Stirling engine. It is hoped that successful development of loss post-processors will facilitate the improvement of the optimization capability of Stirling engine analysis codes through better understanding of the heat transfer and power losses. It is also anticipated that the incorporation of a successful thermal nonequilibrium model of the regenerator in Stirling engine CFD analysis codes, will improve our ability to accurately model Stirling regenerators relative to current multidimensional thermal-equilibrium porous media models.

  2. mit-o-matic: a comprehensive computational pipeline for clinical evaluation of mitochondrial variations from next-generation sequencing datasets.

    PubMed

    Vellarikkal, Shamsudheen Karuthedath; Dhiman, Heena; Joshi, Kandarp; Hasija, Yasha; Sivasubbu, Sridhar; Scaria, Vinod

    2015-04-01

    The human mitochondrial genome has been reported to have a very high mutation rate as compared with the nuclear genome. A large number of mitochondrial mutations show significant phenotypic association and are involved in a broad spectrum of diseases. In recent years, there has been a remarkable progress in the understanding of mitochondrial genetics. The availability of next-generation sequencing (NGS) technologies have not only reduced sequencing cost by orders of magnitude but has also provided us good quality mitochondrial genome sequences with high coverage, thereby enabling decoding of a number of human mitochondrial diseases. In this study, we report a computational and experimental pipeline to decipher the human mitochondrial DNA variations and examine them for their clinical correlation. As a proof of principle, we also present a clinical study of a patient with Leigh disease and confirmed maternal inheritance of the causative allele. The pipeline is made available as a user-friendly online tool to annotate variants and find haplogroup, disease association, and heteroplasmic sites. The "mit-o-matic" computational pipeline represents a comprehensive cloud-based tool for clinical evaluation of mitochondrial genomic variations from NGS datasets. The tool is freely available at http://genome.igib.res.in/mitomatic/.

  3. Scintillator material

    DOEpatents

    Anderson, David F.; Kross, Brian J.

    1994-01-01

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

  4. Scintillator material

    DOEpatents

    Anderson, David F.; Kross, Brian J.

    1992-01-01

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

  5. Scintillator material

    DOEpatents

    Anderson, D.F.; Kross, B.J.

    1994-06-07

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

  6. Scintillator material

    DOEpatents

    Anderson, D.F.; Kross, B.J.

    1992-07-28

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

  7. Modeling Electrostatic Fields Generated by Internal Charging of Materials in Space Radiation Environments

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.

    2011-01-01

    Internal charging is a risk to spacecraft in energetic electron environments. DICTAT, NU MIT computational codes are the most widely used engineering tools for evaluating internal charging of insulator materials exposed to these environments. Engineering tools are designed for rapid evaluation of ESD threats, but there is a need for more physics based models for investigating the science of materials interactions with energetic electron environments. Current tools are limited by the physics included in the models and ease of user implementation .... additional development work is needed to improve models.

  8. Energy Materials.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Public Instruction, Des Moines.

    These resource materials, developed for use by teachers in the elementary and secondary schools, are designed to provide the teacher with a bibliography, questions and answeres, and suggested classroom activities all relating to the energy problem. The materials are designed to develop a conservation ethic and greater understanding of our energy…

  9. Materials Repurposed

    ERIC Educational Resources Information Center

    White, Orvil L.; Townsend, J. Scott

    2008-01-01

    Few teachers find themselves with the support to purchase all of the materials they ideally need to supply their classrooms. Buying one or two simple, ready-made items can put a serious strain on anyone's budget. However, materials for science in the classroom need not be prefabricated or expensive. By looking at the function and purpose of any…

  10. Cermet materials

    DOEpatents

    Kong, Peter C.

    2008-12-23

    A self-cleaning porous cermet material, filter and system utilizing the same may be used in filtering particulate and gaseous pollutants from internal combustion engines having intermetallic and ceramic phases. The porous cermet filter may be made from a transition metal aluminide phase and an alumina phase. Filler materials may be added to increase the porosity or tailor the catalytic properties of the cermet material. Additionally, the cermet material may be reinforced with fibers or screens. The porous filter may also be electrically conductive so that a current may be passed therethrough to heat the filter during use. Further, a heating element may be incorporated into the porous cermet filter during manufacture. This heating element can be coated with a ceramic material to electrically insulate the heating element. An external heating element may also be provided to heat the cermet filter during use.

  11. Composite material

    DOEpatents

    Hutchens, Stacy A.; Woodward, Jonathan; Evans, Barbara R.; O'Neill, Hugh M.

    2012-02-07

    A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

  12. Genomic insights into growth and survival of supercritical-CO2 tolerant bacterium MIT0214 under conditions associated with geologic carbon dioxide sequestration

    NASA Astrophysics Data System (ADS)

    Peet, K. C.; Freedman, A. J.; Hernandez, H.; Thompson, J. R.

    2011-12-01

    Carbon capture and storage (CCS) of CO2 has the potential to significantly reduce the emissions of greenhouse gasses associated with fossil fuel combustion. The largest potential for storing captured CO2 in the United Sates is in deep geologic saline formations. Currently, little is known about the effects of CO2 storage on biologically active microbial communities found in the deep earth biosphere. Therefore, to investigate how deep earth microbial communities will be affected by the storage of CO2 we have enriched for a microbial consortium from the saline formation waters of the Frio 2 project site (Texas Gulf Coast) that is capable of growth in nutrient media under a supercritical CO2 headspace (Hernandez, et al). The cultivation of actively growing cells in an environment containing scCO2 is unexpected based on previous experimental evidence of microbial sterilization attributed to the acidic, desiccating, and solvent-like properties of scCO2. We have isolated strain MIT0214 from this supercritical CO2 based enrichment and have sequenced its genome using the Illumina platform followed by de novo assembly of reads and targeted Sanger sequencing to reduce gaps in the draft assembly. The genome of strain MIT0214 is approximately 5,551,062 base pairs with 35% GC-content and is most similar to nonpathogenic Bacillus cereus strain ATCC 14597. Annotation of the draft assembly of the MIT0214 genome by the Rapid Annotation using Subsystem Technology (RAST) server revealed 5538 coding sequences where 4145 of the coding sequences were assigned putative functions. These functions were enriched in cell wall and capsule formation, phage/prophage and plasmids, gene regulation and signaling, and nitrogen and sulfur metabolism relative to the genome of the most closely-related surface-isolated B. cereus reference (ATCC 14597) and in total 773,416 bp of the MIT0214 genome content was distinct from the B. cereus reference. Notably, this set of distinct sequences were most

  13. Insulation Material

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Manufactured by Hitco Materials Division of Armco, Inc. a ceramic fiber insulation material known as Refrasil has been used extensively as a heat-absorbing ablative reinforcement for such space systems as rocket motor nozzles, combustion chambers, and re-entry shields. Refrasil fibers are highly porous and do not melt or vaporize until fibers exceed 3,100 degrees Fahrenheit. Due to these and other properties, Refrasil has found utility in a number of industrial high temperature applications where glass, asbestos and other materials fail. Hitco used this insulation to assist Richardson Co., Inc. in the manufacturing of hard rubber and plastic molded battery cases.

  14. VizieR Online Data Catalog: MGIV (Fourth MIT-Green Bank) 5GHz Survey (Griffith+ 1991)

    NASA Astrophysics Data System (ADS)

    Griffith, M.; Langston, G.; Heflin, M.; Conner, S.; Burke, B.

    1998-10-01

    The MIT-Green Bank IV (MG IV) 5 GHz survey covers 0.504 sr of sky in the right ascension range 15.5 to 2.5 hours, between +37.00 and +50.98 degrees declination (B1950). The final MG IV catalog contains 3427 sources detected with a signal-to-noise ratio greater than 5. The catalog was produced from two separate north and south surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope. The north survey was produced from data collected while scanning the telescope north from +39.0 to +50.98 degrees declination and the south survey from data collected from scans from +48.98 to +37.00 degrees declination. The completeness and reliability of the final source list is checked by examination of north and south source lists in a twice observed comparison region, lying between +39.15 and +48.83 degrees declination and excluding the area between +/-10 degrees Galactic latitude. The comparison region covers 0.270 sr of sky and contains 1094 sources. In this region, the MG IV catalog contains 423 sources brighter than 90 mJy and is shown to be 99.1 +/- 1.2% complete at this flux density level. Spectral indices are computed for sources identified in the NRAO 1400 MHz Survey (published by Condon and Broderick in 1985). A comparison of the spectral index distributions between +/- 10 and outside of +/- 10 degrees Galactic latitude is presented. (1 data file).

  15. Complex Materials

    SciTech Connect

    Cooper, Valentino

    2014-04-17

    Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

  16. CURRICULUM MATERIALS.

    ERIC Educational Resources Information Center

    New Jersey State Dept. of Education, Trenton.

    MATERIALS ARE LISTED BY 36 TOPICS ARRANGED IN ALPHABETICAL ORDER. TOPICS INCLUDE APPRENTICE TRAINING, BAKING, DRAFTING, ENGLISH, GLASSBLOWING, HOME ECONOMICS, INDUSTRIAL CHEMISTRY, MACHINE SHOP, NEEDLE TRADES, REFRIGERATION, AND UPHOLSTERY. PRICES ARE GIVEN FOR EACH ITEM. (EL)

  17. Contrast Materials

    MedlinePlus

    ... or other reactions to contrast materials are rare, radiology departments are well-equipped to deal with them. ... is given. However, both the American College of Radiology (ACR) and the European Society of Urogenital Radiology ...

  18. Complex Materials

    ScienceCinema

    Cooper, Valentino

    2016-07-12

    Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

  19. Reference Materials

    NASA Astrophysics Data System (ADS)

    Merkus, Henk G.

    Reference materials for measurement of particle size and porosity may be used for calibration or qualification of instruments or for validation of operating procedures or operators. They cover a broad range of materials. On the one hand there are the certified reference materials, for which governmental institutes have certified one or more typical size or porosity values. Then, there is a large group of reference materials from commercial companies. And on the other hand there are typical products in a given line of industry, where size or porosity values come from the analysis laboratory itself or from some round-robin test in a group of industrial laboratories. Their regular application is essential for adequate quality control of particle size and porosity measurement, as required in e.g., ISO 17025 on quality management. In relation to this, some quality requirements for certification are presented.

  20. Perforated Materials

    NASA Technical Reports Server (NTRS)

    1981-01-01

    National Perforating Corporation (NPC) is a supplier of perforated metals, plastics, and other materials. In production of screens, walkways, and other products for all industries, NPC sought to determine the safe loading of such perforated metal products. NERAC supplied NPC an informational package which included the identification of a firm that already accomplished test and evaluation of the strengths of perforated materials. Using the information available from that firm saved NPC money and time.

  1. Propulsion materials

    SciTech Connect

    Wall, Edward J.; Sullivan, Rogelio A.; Gibbs, Jerry L.

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  2. Detection of fissionable materials in cargoes using monochromatic photon radiography

    NASA Astrophysics Data System (ADS)

    Danagoulian, Areg; Lanza, Richard; O'Day, Buckley; LNSP Team

    2015-04-01

    The detection of Special Nuclear Materials (e.g. Pu and U) and nuclear devices in the commercial cargo traffic is one of the challenges posed by the threat of nuclear terrorism. Radiography and active interrogation of heavily loaded cargoes require ~ 1 - 10MeV photons for penetration. In a proof-of-concept system under development at MIT, the interrogating monochromatic photon beam is produced via a 11B(d , nγ) 12C reaction. To achieve this, a boron target is used along with the 3 MeV d+ RFQ accelerator at MIT-Bates. The reactions results in the emission of very narrow 4.4 MeV and 15.1 MeV gammas lines. The photons, after traversing the cargo, are detected by an array of NaI(Tl) detectors. A spectral analysis of the transmitted gammas allows to independently determine the areal density and the atomic number (Z) of the cargo. The proposed approach could revolutionize cargo inspection, which, in its current fielded form has to rely on simple but high dose bremsstrahlung sources. Use of monochromatic sources would significantly reduce the necessary dose and allow for better determination of the cargo's atomic number. The general methodology will be described and the preliminary results from the proof-of-concept system will be presented and discussed. Supported by NSF/DNDO Collaborative Research ARI-LA Award ECCS-1348328.

  3. Parachute materials

    SciTech Connect

    Peterson, C.W.; Johnson, D.W.

    1987-06-01

    The purpose of this paper is to present guidelines for the use of Kevlar and nylon materials in modern parachute systems. Nylon has been used in parachutes for many years, so this discussion will place emphasis upon Kevlar material properties and their application to parachute design and construction. Kevlar-29 is an aramid fiber manufactured by DuPont and is being used on parachute systems requiring high strength-to-weight ratios or sustained strength at high temperatures. Tests of parachutes using Kevlar webbing, braided cords, ribbons, and thread have demonstrated that these Kevlar materials can be used successfully in ribbon parachutes with no detrimental effects on performance. A few changes must be made in the design of a ribbon parachute to accommodate Kevlar's high modulus. Examples of parachutes that use Kevlar suspension lines, radials, ribbons, reefing lines, bridles, and skirt bands are presented to show that they are much lighter and more resistant to aerodynamic heating than all-nylon parachutes. Nylon continues to be an important material for high-performance parachute systems, however. New nylon weaves have resulted in lighter weight, stronger ribbon materials with excellent sewability characteristics.

  4. Materials Overview

    NASA Technical Reports Server (NTRS)

    Draper, Robert

    2001-01-01

    The Materials and Structures for High Performance project has made excellent progress in the development of advanced high-temperature materials and computational materials science tools to enable high-performance, hgh-efficiency, and environmentally compatible propulsion systems. Ceramic matrix composite (CMC) systems with 2700 O F temperature capability are initially being developed for low NO, combustor liners and turbine vanes. The feasibility of pushing CMC technologies to 3000 O F through revolutionary concepts is also being pursued. Achieving fuel savings of 8 to 15 percent requires higher turbine inlet temperatures as well as reductions in engine weight. An advanced disk alloy has been evaluated for application in future engines. Advanced thermal barrier coatings (TBC s) will enable 3200 O F turbine rotor inlet temperature capability. Advanced alloy development and the development of computational tools for the design of these future alloys will further enable attainment of these goals. Innovative lightweight materials, and structural and nozzle aerodynamic concepts are also being developed to reduce the weight of engine static structures to contribute toward overall fuel savings. Rig tests will demonstrate long-term durability of CMC linersand vanes and advanced turbine airfoil alloy systems, as well as fabricability of components with the highest payoff potential using the lightweight materials and structures concepts being developed.

  5. Hardfacing material

    SciTech Connect

    Branagan, Daniel J.

    2012-01-17

    A method of producing a hard metallic material by forming a mixture containing at least 55% iron and at least one of boron, carbon, silicon and phosphorus. The mixture is formed into an alloy and cooled to form a metallic material having a hardness of greater than about 9.2 GPa. The invention includes a method of forming a wire by combining a metal strip and a powder. The metal strip and the powder are rolled to form a wire containing at least 55% iron and from two to seven additional elements including at least one of C, Si and B. The invention also includes a method of forming a hardened surface on a substrate by processing a solid mass to form a powder, applying the powder to a surface to form a layer containing metallic glass, and converting the glass to a crystalline material having a nanocrystalline grain size.

  6. Layered materials

    NASA Astrophysics Data System (ADS)

    Johnson, David; Clarke, Simon; Wiley, John; Koumoto, Kunihito

    2014-06-01

    Layered compounds, materials with a large anisotropy to their bonding, electrical and/or magnetic properties, have been important in the development of solid state chemistry, physics and engineering applications. Layered materials were the initial test bed where chemists developed intercalation chemistry that evolved into the field of topochemical reactions where researchers are able to perform sequential steps to arrive at kinetically stable products that cannot be directly prepared by other approaches. Physicists have used layered compounds to discover and understand novel phenomena made more apparent through reduced dimensionality. The discovery of charge and spin density waves and more recently the remarkable discovery in condensed matter physics of the two-dimensional topological insulating state were discovered in two-dimensional materials. The understanding developed in two-dimensional materials enabled subsequent extension of these and other phenomena into three-dimensional materials. Layered compounds have also been used in many technologies as engineers and scientists used their unique properties to solve challenging technical problems (low temperature ion conduction for batteries, easy shear planes for lubrication in vacuum, edge decorated catalyst sites for catalytic removal of sulfur from oil, etc). The articles that are published in this issue provide an excellent overview of the spectrum of activities that are being pursued, as well as an introduction to some of the most established achievements in the field. Clusters of papers discussing thermoelectric properties, electronic structure and transport properties, growth of single two-dimensional layers, intercalation and more extensive topochemical reactions and the interleaving of two structures to form new materials highlight the breadth of current research in this area. These papers will hopefully serve as a useful guideline for the interested reader to different important aspects in this field and

  7. Squishy Materials

    NASA Astrophysics Data System (ADS)

    Habdas, Piotr; Weeks, Eric R.; Lynn, David G.

    2006-05-01

    Most people do not realize that many substances they use in the kitchen and the bathroom are not simple liquids or solids. Everyone is familiar with three states of matter: solids, liquids, and gases. However, creams, shampoo, toothpaste, and ketchup all have properties of both liquids and solids. This paper describes demonstrations and laboratory exercises1 that show intriguing properties of squishy substances, defined as materials that are not unambiguously solid, liquid, or gas. Unlike some areas of physics, the concepts behind squishy materials are understandable even by beginning students. Squishy physics can be used to show physics questions arising from everyday life and to convey the excitement of current research.

  8. ADAPTATION OF CRACK GROWTH DETECTION TECHNIQUES TO US MATERIAL TEST REACTORS

    SciTech Connect

    A. Joseph Palmer; Sebastien P. Teysseyre; Kurt L. Davis; Gordon Kohse; Yakov Ostrovsky; David M. Carpenter; Joy L. Rempe

    2015-04-01

    A key component in evaluating the ability of Light Water Reactors to operate beyond 60 years is characterizing the degradation of materials exposed to radiation and various water chemistries. Of particular concern is the response of reactor materials to Irradiation Assisted Stress Corrosion Cracking (IASCC). Some test reactors outside the United States, such as the Halden Boiling Water Reactor (HBWR), have developed techniques to measure crack growth propagation during irradiation. The basic approach is to use a custom-designed compact loading mechanism to stress the specimen during irradiation, while the crack in the specimen is monitored in-situ using the Direct Current Potential Drop (DCPD) method. In 2012 the US Department of Energy commissioned the Idaho National Laboratory and the MIT Nuclear Reactor Laboratory (MIT NRL) to take the basic concepts developed at the HBWR and adapt them to a test rig capable of conducting in-pile IASCC tests in US Material Test Reactors. The first two and half years of the project consisted of designing and testing the loader mechanism, testing individual components of the in-pile rig and electronic support equipment, and autoclave testing of the rig design prior to insertion in the MIT Reactor. The load was applied to the specimen by means of a scissor like mechanism, actuated by a miniature metal bellows driven by pneumatic pressure and sized to fit within the small in-core irradiation volume. In addition to the loader design, technical challenges included developing robust connections to the specimen for the applied current and voltage measurements, appropriate ceramic insulating materials that can endure the LWR environment, dealing with the high electromagnetic noise environment of a reactor core at full power, and accommodating material property changes in the specimen, due primarily to fast neutron damage, which change the specimen resistance without additional crack growth. The project culminated with an in

  9. Konstruieren von Pkw-Karosserien: Grundlagen, Elemente und Baugruppen, Vorschriftenübersicht, Beispiele mit CATIA V4 und V5

    NASA Astrophysics Data System (ADS)

    Grabner, Jörg; Nothhaft, Richard

    Die Faszination, die vom Auto ausgeht, ist und bleibt ungebrochen. Entsprechend interessant ist es, sich vor dem Hintergrund konventioneller Konstruktionstechniken über die virtuelle Produktentwicklung von Pkw-Karosserien an modernen CAD-Arbeitsplätzen informieren zu können. Die Autoren führen in die Grundlagen ein und zeigen anhand von Beispielen und zahlreichen Abbildungen, wie mit dem System CATIA der Rohbau sowie die Ausstattung innen und au=C3=9Fen konstruiert werden. Darüber hinaus wird das so genannte "Package" an Beispielen beschrieben, also das Management und die Harmonisierung der Anforderungen an die Bauräume (z.

  10. BIOBASED MATERIALS

    EPA Science Inventory

    Biobased materials refer to products that mainly consist of a substance (or substances) derived from living matter (biomass) and either occur naturally or are synthesized, or it may refer to products made by processes that use biomass. Following a strict definition, many common m...

  11. Experiments on a strongly correlated material: photoresponse, phase diagram and hydrogen doping of vanadium dioxide

    NASA Astrophysics Data System (ADS)

    Kasirga, T. Serkan

    The metal-insulator transition (MIT) in vanadium dioxide (VO2) has attracted waves of attention after its rst observation by Morin in 1959. There are several reasons for the interest in this material. First, its metal-insulator transition is at an easily accessible temperature which allows investigators to study the eect of strong electronic correlations with little eort. Second reason is VO2 oers many applications, although most of them are mundane, a few may have signicant eects on dierent areas of technology. However, even after over half a century there is still a debate about the nature of the MIT and non of the applications proposed have been realized. The main culprit for this is the diculties in studying the bulk crystals of VO 2. In bulk crystals, defects in the crystal, impurities and domain structure causes irreproducible results. This combined with the theoretical challenges made studying VO2 and realization of applications impractical. However, recent discovery of the growth technique for growing the nano-scale crystals, revitalized the interest in VO2. In this dissertation I present the experimental studies that we performed on VO2. I discussed the ndings from three major studies we performed; photoresponse, finding the strain-temperature phase diagram and hydrogen doping of VO2. We used scanning photocurrent microscopy technique to reveal the light-matter interaction in VO2. Suspended nanobeam devices are used in the experiments and results revealed that photoresponse of VO2 is dominated by the thermal eects and there is no photovoltaic contribution. Results are published in Nature Nanotechnology in 2012 . In the second study, we determined the strain-temperature phase stability diagram of VO2. This is the first ever determination of the phase diagram of a solid state phase transition. Also our studies revealed that the triple point coincides with the critical point, which has important implications for both theoretical studies of the MIT in VO 2 and

  12. Materials Science

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Materials Science Program is structured so that NASA s headquarters is responsible for the program content and selection, through the Enterprise Scientist, and MSFC provides for implementation of ground and flight programs with a Discipline Scientist and Discipline Manager. The Discipline Working Group of eminent scientists from outside of NASA acts in an advisory capacity and writes the Discipline Document from which the NRA content is derived. The program is reviewed approximately every three years by groups such as the Committee on Microgravity Research, the National Materials Advisory Board, and the OBPR Maximization and Prioritization (ReMaP) Task Force. The flight program has had as many as twenty-six principal investigators (PIs) in flight or flight definition stage, with the numbers of PIs in the future dependent on the results of the ReMaP Task Force and internal reviews. Each project has a NASA-appointed Project Scientist, considered a half-time job, who assists the PI in understanding and preparing for internal reviews such as the Science Concept Review and Requirements Definition Review. The Project Scientist also insures that the PI gets the maximum science support from MSFC, represents the PI to the MSFC community, and collaborates with the Project Manager to insure the project is well-supported and remains vital. Currently available flight equipment includes the Materials Science Research Rack (MSRR-1) and Microgravity Science Glovebox. Ground based projects fall into one or more of several categories. Intellectual Underpinning of Flight Program projects include theoretical studies backed by modeling and computer simulations; bring to maturity new research, often by young researchers, and may include preliminary short duration low gravity experiments in the KC-135 aircraft or drop tube; enable characterization of data sets from previous flights; and provide thermophysical property determinations to aid PIs. Radiation Shielding and preliminary In

  13. Material Reseach

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Rathz, Tom

    1996-01-01

    Containerless processing experiments in space and in ground-based facilities such as the Drop Tube Facility at Marshall Space Flight Center provide a unique capabilty to study materials processing phenomena without the influence of walls on nucleation processes. This research will further develop that capability by new experiments with immesible systems. Nucleation and undercooling phenomena will be monitored using infra-red temperature measurements.

  14. Prosthesis Material

    NASA Technical Reports Server (NTRS)

    1995-01-01

    In this photograph, Sandra Rossi user her NASA-developed prosthesis for the first time. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.

  15. Prosthesis Material

    NASA Technical Reports Server (NTRS)

    1995-01-01

    In this photograph, James Carden uses a NASA-developed prosthesis to moved planks around his home. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.

  16. Prosthesis Material

    NASA Technical Reports Server (NTRS)

    2004-01-01

    In this photograph, Amputee Amie Bradly uses a NASA-developed prosthesis to paint her fingernails. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.

  17. Fullerene materials

    SciTech Connect

    Malhotra, R.; Ruoff, R.S.; Lorents, D.C.

    1995-04-01

    Fullerenes are all-carbon cage molecules. The most celebrated fullerene is the soccer-ball shaped C{sub 60}, which is composed of twenty hexagons and twelve pentagons. Because its structure is reminiscent of the geodesic domes of architect R. Buckminster Fuller, C{sub 60} is called buckminsterfullerene, and all the materials in the family are designated fullerenes. Huffman and Kraetschmer`s discovery unleashed activity around the world as scientists explored production methods, properties, and potential uses of fullerenes. Within a short period, methods for their production in electric arcs, plasmas, and flames were discovered, and several companies began selling fullerenes to the research market. What is remarkable is that in all these methods, carbon atoms assemble themselves into cage structures. The capability for self-assembly points to some inherent stability of these structures that allows their formation. The unusual structure naturally leads to unusual properties. Among them are ready solubility in solvents and a relatively high vapor pressure for a pure carbon material. The young fullerene field has already produced a surprising array of structures for the development of carbon-base materials having completely new and different properties from any that were previously possible.

  18. FOREWORD: Materials metrology Materials metrology

    NASA Astrophysics Data System (ADS)

    Bennett, Seton; Valdés, Joaquin

    2010-04-01

    It seems that so much of modern life is defined by the materials we use. From aircraft to architecture, from cars to communications, from microelectronics to medicine, the development of new materials and the innovative application of existing ones have underpinned the technological advances that have transformed the way we live, work and play. Recognizing the need for a sound technical basis for drafting codes of practice and specifications for advanced materials, the governments of countries of the Economic Summit (G7) and the European Commission signed a Memorandum of Understanding in 1982 to establish the Versailles Project on Advanced Materials and Standards (VAMAS). This project supports international trade by enabling scientific collaboration as a precursor to the drafting of standards. The VAMAS participants recognized the importance of agreeing a reliable, universally accepted basis for the traceability of the measurements on which standards depend for their preparation and implementation. Seeing the need to involve the wider metrology community, VAMAS approached the Comité International des Poids et Mesures (CIPM). Following discussions with NMI Directors and a workshop at the BIPM in February 2005, the CIPM decided to establish an ad hoc Working Group on the metrology applicable to the measurement of material properties. The Working Group presented its conclusions to the CIPM in October 2007 and published its final report in 2008, leading to the signature of a Memorandum of Understanding between VAMAS and the BIPM. This MoU recognizes the work that is already going on in VAMAS as well as in the Consultative Committees of the CIPM and establishes a framework for an ongoing dialogue on issues of materials metrology. The question of what is meant by traceability in the metrology of the properties of materials is particularly vexed when the measurement results depend on a specified procedure. In these cases, confidence in results requires not only traceable

  19. Shock transmission and reflection from a material interface and subsequent reflection from a hard boundary

    SciTech Connect

    Hurricane, O A; Miller, P L

    1998-11-20

    As a shock wave passes through a material interface into a region of higher density (the receiver material), a trans- mitted and reflected shock wave are both generated and the interface is set into motion. The speeds of the transmitted shock, reflected shock, and interface are related to the ini- tial shock speed and material properties via a set of coupled nonlinear equations that, in general, cannot be easily solved analytically. In this report, we derive the equations which describe this process and we document a numerical routine which solves the nonlinear equations. We then go on to solve the problem of finding the position where the interface col- lides with the transmitted shock wave once the transmitted shock wave is reflected from an impenetrable boundary lo- cated somewhere away from the initial material interface. Fi- nally, we compare the analytical predictions with the CALE simulation running in 1-D.

  20. Alloy materials

    DOEpatents

    Hans Thieme, Cornelis Leo; Thompson, Elliott D.; Fritzemeier, Leslie G.; Cameron, Robert D.; Siegal, Edward J.

    2002-01-01

    An alloy that contains at least two metals and can be used as a substrate for a superconductor is disclosed. The alloy can contain an oxide former. The alloy can have a biaxial or cube texture. The substrate can be used in a multilayer superconductor, which can further include one or more buffer layers disposed between the substrate and the superconductor material. The alloys can be made a by process that involves first rolling the alloy then annealing the alloy. A relatively large volume percentage of the alloy can be formed of grains having a biaxial or cube texture.

  1. Casting materials

    DOEpatents

    Chaudhry, Anil R.; Dzugan, Robert; Harrington, Richard M.; Neece, Faurice D.; Singh, Nipendra P.

    2011-06-14

    A foam material comprises a liquid polymer and a liquid isocyanate which is mixed to make a solution that is poured, injected or otherwise deposited into a corresponding mold. A reaction from the mixture of the liquid polymer and liquid isocyanate inside the mold forms a thermally collapsible foam structure having a shape that corresponds to the inside surface configuration of the mold and a skin that is continuous and unbroken. Once the reaction is complete, the foam pattern is removed from the mold and may be used as a pattern in any number of conventional casting processes.

  2. Construction material

    DOEpatents

    Wagh, Arun S.; Antink, Allison L.

    2008-07-22

    A structural material of a polystyrene base and the reaction product of the polystyrene base and a solid phosphate ceramic is applied as a slurry which includes one or more of a metal oxide or a metal hydroxide with a source of phosphate to produce a phosphate ceramic and a poly (acrylic acid or acrylate) or combinations or salts thereof and polystyrene or MgO applied to the polystyrene base and allowed to cure so that the dried aqueous slurry chemically bonds to the polystyrene base. A method is also disclosed of applying the slurry to the polystyrene base.

  3. Photovoltaic Materials

    SciTech Connect

    Duty, C.; Angelini, J.; Armstrong, B.; Bennett, C.; Evans, B.; Jellison, G. E.; Joshi, P.; List, F.; Paranthaman, P.; Parish, C.; Wereszczak, A.

    2012-10-15

    The goal of the current project was to help make the US solar industry a world leader in the manufacture of thin film photovoltaics. The overall approach was to leverage ORNL’s unique characterization and processing technologies to gain a better understanding of the fundamental challenges for solar cell processing and apply that knowledge to targeted projects with industry members. ORNL has the capabilities in place and the expertise required to understand how basic material properties including defects, impurities, and grain boundaries affect the solar cell performance. ORNL also has unique processing capabilities to optimize the manufacturing process for fabrication of high efficiency and low cost solar cells. ORNL recently established the Center for Advanced Thin-film Systems (CATS), which contains a suite of optical and electrical characterization equipment specifically focused on solar cell research. Under this project, ORNL made these facilities available to industrial partners who were interested in pursuing collaborative research toward the improvement of their product or manufacturing process. Four specific projects were pursued with industrial partners: Global Solar Energy is a solar industry leader in full scale production manufacturing highly-efficient Copper Indium Gallium diSelenide (CIGS) thin film solar material, cells and products. ORNL worked with GSE to develop a scalable, non-vacuum, solution technique to deposit amorphous or nanocrystalline conducting barrier layers on untextured stainless steel substrates for fabricating high efficiency flexible CIGS PV. Ferro Corporation’s Electronic, Color and Glass Materials (“ECGM”) business unit is currently the world’s largest supplier of metallic contact materials in the crystalline solar cell marketplace. Ferro’s ECGM business unit has been the world's leading supplier of thick film metal pastes to the crystalline silicon PV industry for more than 30 years, and has had operational cells and

  4. Recent KBO (Pluto/Charon and beyond, including Quaoar) Occultation Observations by the Williams College Team as part of the Williams-MIT Collaboration

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.; Babcock, B. A.; Davis, A. B.; Pandey, S.; Lu, M.; Rogosinski, Z.; Person, M. J.; Bosh, A. S.; Zangari, A. M.; Zuluaga, C. A.; Gulbis, A. S.; Naranjo, O.; Navas, G.; Zerpa, L.; Villarreal, J.; Rojo, P.; Förster, F.; Servajean, E.

    2013-10-01

    The Williams College-MIT collaboration has observed numerous occultations of stars by Pluto/Charon and other Kuiper-belt objects (www.stellaroccultations.info), since its establishment three decades ago with an attempted discovery of Neptune's rings in 1983. In this paper, we describe several recent occultation observations, both successful and (for reasons of path uncertainties and/or weather) unsuccessful. Light curves made or arranged by Williams College faculty and students were used together with light curves by MIT colleagues and others to study Pluto's atmosphere and Charon's size, to discover one of the highest-known solar-system albedos (KBO 55636), and to attempt to study 1000-km-diameter Quaoar. Observations discussed include light curves for KBO 55636 on 9 October 2009 from Hawaii; Pluto on 3/4 July 2010 from Chile, 22 May 2011 from Williamstown, Massachusetts, 23 June 2011 from Hawaii (in support of SOFIA observations of Pluto's atmosphere, discussed in an article in press in AJ and of the pair of Pluto/Charon occultations of the same star), and 4 May 2013 (Bosh et al., this conference) and 15 July 2013 from Williamstown; Charon on 15 June 2013 from Williamstown; Quaoar from a picket fence ranging from Chile through Venezuela (with a detection there) to Massachusetts on July 8/9 and in South Africa on 12 July 2013. This work was supported in part by NASA Planetary Astronomy grants NNX08AO50G and NNH11ZDA001N to Williams College, NNX10AB27G to MIT, and USRA grant #8500-98-003 to Lowell Observatory. We thank Steven P. Souza at Williams; Steven Levine at Lowell Obs.; Jennifer G. Winters (GSU) in Chile; Richard Rojas/Jorge Moreno in Venezuela; Scott Sheppard; Federica Bianco; David Osip; and others. ZR (Vassar '14) was a Keck Northeast Astronomy Consortium Summer Fellow at Williams College, supported by an NSF/REU grant to the Keck Northeast Astronomy Consortium. ES: partial support from Programa Nacional de Becas de Postgrado (CONICYT Grant 21110496). FF

  5. PREFACE: Superconducting materials Superconducting materials

    NASA Astrophysics Data System (ADS)

    Charfi Kaddour, Samia; Singleton, John; Haddad, Sonia

    2011-11-01

    The discovery of superconductivity in 1911 was a great milestone in condensed matter physics. This discovery has resulted in an enormous amount of research activity. Collaboration among chemists and physicists, as well as experimentalists and theoreticians has given rise to very rich physics with significant potential applications ranging from electric power transmission to quantum information. Several superconducting materials have been synthesized. Crucial progress was made in 1987 with the discovery of high temperature superconductivity in copper-based compounds (cuprates) which have revealed new fascinating properties. Innovative theoretical tools have been developed to understand the striking features of cuprates which have remained for three decades the 'blue-eyed boy' for researchers in superconductor physics. The history of superconducting materials has been notably marked by the discovery of other compounds, particularly organic superconductors which despite their low critical temperature continue to attract great interest regarding their exotic properties. Last but not least, the recent observation of superconductivity in iron-based materials (pnictides) has renewed hope in reaching room temperature superconductivity. However, despite intense worldwide studies, several features related to this phenomenon remain unveiled. One of the fundamental key questions is the mechanism by which superconductivity takes place. Superconductors continue to hide their 'secret garden'. The new trends in the physics of superconductivity have been one of the two basic topics of the International Conference on Conducting Materials (ICoCoM2010) held in Sousse,Tunisia on 3-7 November 2010 and organized by the Tunisian Physical Society. The conference was a nice opportunity to bring together participants from multidisciplinary domains in the physics of superconductivity. This special section contains papers submitted by participants who gave an oral contribution at ICoCoM2010

  6. Superconducting materials

    SciTech Connect

    Ruvalds, J.

    1992-01-01

    Our research on high temperatures superconductors has produced novel insights for the normal state properties of copper oxides that have been discovered in the last few years. Advances in materials preparation have produced singly crystal samples, and sophisticated surface cleavage techniques have unveiled truly metallic behavior in many respects. Thus, the recent confirmation of a Fermi surface in several cuprate superconductors by photoemission spectroscopy has aroused interest in experimental features which heretofore were in apparent contrast to the expectations for a conventional Fermi Liquid. Our group has discovered that nested'' nearly parallel sections of the electron orbits yields an anomalous response which influences the electrical resistivity, optical reflectance, Raman spectrum, and neutron scattering cross section. Our analysis has provided an explanation for seemingly disparate experimental features of high temperature superconductors using consistent values for the electron-electron coupling and the plasma frequency. Our results include the following properties of high temperature superconductors: Nested Fermi Liquid Response in High Temperature Superconductors, Optical Reflectivity and Electron Energy Loss Data, Raman Spectra, Neutron Scattering Cross Section and Scaling, and Prospects for New Superconductors.

  7. Biointegrating Materials

    NASA Astrophysics Data System (ADS)

    Amédée, J.; Bordenave, L.; Durrieu, M.-C.; Fricain, J.-C.; Pothuaud, L.

    The extraordinary increase in human longevity explains the growing need for replacement organs. The remarkable successes of conventional transplants (associated with the development of effective antirejection drugs and improved control of their administration) are also accompanied by certain drawbacks. First on the list is an inadequate supply of replacement organs: the number of candidates for transplants grows larger, opposition to the removal of organs increases, and the number of transplants has reached a ceiling. Furthermore, it has come to light over the past few years that organ transplants carry a significant risk of transmitting pathogens. Finally, the main drawback lies in the need to pursue an immunosuppression treatment. Scientists and doctors have long been in search of alternatives to human organ transplants. According to the definition drawn up in Chester in 1986 at the Consensus Conference organised under the aegis of the European Society for Biomaterials, biomaterials are non-viable materials used in a medical device and destined to interact with biological systems, whether they contribute to the constitution of a diagnostic device, a tissue or organ substitute, or a device designed to provide functional assistance or replacement.

  8. Assessment of MIT and UCB wall condensation tests and of the pre-release RELAP5/MOD3.2 code condensation models

    SciTech Connect

    Shumway, R.W.

    1995-01-01

    In recent years, a new class of reactor designs has been proposed that utilize passive safety systems. General Electric has developed a Simplified Boiling Water Reactor (SBWR) design that relies on such passive systems. The SBWR has two passive cooling systems that involve energy transfer by condensation. These are the isolation condenser system (ICS) and the passive containment cooling systems (PCCS). It is important that such heat transfer phenomena be correctly understood and quantified. The General Electric Company has sponsored tests at the Massachusetts Institute of Technology (MIT) and at the University of California at Berkeley (UCB) to obtain data simulating PCCS conditions. Data was obtained with pure steam, steam-air mixtures and steam-helium mixtures. INEL has been contracted by the NRC to evaluate these tests and assess existing condensation heat transfer correlations against the test data. This report assesses the relevance of the tests to SBWR conditions and shows RELAP5/MOD3.2 predictions of the tests.

  9. Development of the system for visualization of electric conductivity distribution in human brain and its activity by the magnetic induction tomography (MIT) method

    NASA Astrophysics Data System (ADS)

    Sapetsky, S.; Cherepenin, V.; Korjenevsky, A.; Kornienko, V.; Vartanov, A.

    2010-04-01

    Currently rapid development of functional activity researches of human brain sets the problem of reliable and non-invasive detection of mental processes and states. At present we know some traditional methods of rapid and contactless acquisition of brain activity characteristics, such as functional tomography (fMRI) and magnetoencephalography. But these methods have low temporal resolution, complicated and ambiguous association of measured values with information processes in brain. So possibility of MIT application is investigated. Estimation of possibility of such changes registration is performed. Investigations of magnetic field configuration, schematics of transmit-receive modules and numerical algorithms are in progress. It may allow us to register high speed conductivity changes in brain tissues.

  10. Adjustable impedance, force feedback and command language aids for telerobotics (parts 1-4 of an 8-part MIT progress report)

    NASA Technical Reports Server (NTRS)

    Sheridan, Thomas B.; Raju, G. Jagganath; Buzan, Forrest T.; Yared, Wael; Park, Jong

    1989-01-01

    Projects recently completed or in progress at MIT Man-Machine Systems Laboratory are summarized. (1) A 2-part impedance network model of a single degree of freedom remote manipulation system is presented in which a human operator at the master port interacts with a task object at the slave port in a remote location is presented. (2) The extension of the predictor concept to include force feedback and dynamic modeling of the manipulator and the environment is addressed. (3) A system was constructed to infer intent from the operator's commands and the teleoperation context, and generalize this information to interpret future commands. (4) A command language system is being designed that is robust, easy to learn, and has more natural man-machine communication. A general telerobot problem selected as an important command language context is finding a collision-free path for a robot.

  11. Digestive Diseases Materials

    MedlinePlus

    ... NIDDK Health Information NIDDK Home NIDDK Image Library Digestive Disease, Nutrition, and Weight-control Materials Healthy eating, ... Materials Statistics Tip Sheets Catalog Home | Diabetes Materials | Digestive Diseases Materials | Kidney and Urologic Diseases Materials Online ...

  12. Critical Materials Institute

    ScienceCinema

    Alex King

    2016-07-12

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  13. Critical Materials Institute

    SciTech Connect

    Alex King

    2013-01-09

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  14. Deutsche Feste. Sitten und Brauche mit Liedern Gedichten Ratseln. (German Festivities. Habits and Customs Using Songs and Stories).

    ERIC Educational Resources Information Center

    Hawrysz, Ilse, Ed.

    This teacher's guide of supplemental cultural materials includes descriptions of major celebrations and cultural activities of the German people. The text includes songs, poems, and stories about the New Year, carnival, springtime, Easter, fall festivals, and Christmas, as well as a traditional German wedding. (TR)

  15. Gas storage materials, including hydrogen storage materials

    SciTech Connect

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2013-02-19

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  16. Gas storage materials, including hydrogen storage materials

    SciTech Connect

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2014-11-25

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  17. Geopolymer resin materials, geopolymer materials, and materials produced thereby

    DOEpatents

    Seo, Dong-Kyun; Medpelli, Dinesh; Ladd, Danielle; Mesgar, Milad

    2016-03-29

    A product formed from a first material including a geopolymer resin material, a geopolymer resin, or a combination thereof by contacting the first material with a fluid and removing at least some of the fluid to yield a product. The first material may be formed by heating and/or aging an initial geopolymer resin material to yield the first material before contacting the first material with the fluid. In some cases, contacting the first material with the fluid breaks up or disintegrates the first material (e.g., in response to contact with the fluid and in the absence of external mechanical stress), thereby forming particles having an external dimension in a range between 1 nm and 2 cm.

  18. Materials Project: A Materials Genome Approach

    DOE Data Explorer

    Ceder, Gerbrand [MIT; Persson, Kristin [LBNL

    Technological innovation - faster computers, more efficient solar cells, more compact energy storage - is often enabled by materials advances. Yet, it takes an average of 18 years to move new materials discoveries from lab to market. This is largely because materials designers operate with very little information and must painstakingly tweak new materials in the lab. Computational materials science is now powerful enough that it can predict many properties of materials before those materials are ever synthesized in the lab. By scaling materials computations over supercomputing clusters, this project has computed some properties of over 80,000 materials and screened 25,000 of these for Li-ion batteries. The computations predicted several new battery materials which were made and tested in the lab and are now being patented. By computing properties of all known materials, the Materials Project aims to remove guesswork from materials design in a variety of applications. Experimental research can be targeted to the most promising compounds from computational data sets. Researchers will be able to data-mine scientific trends in materials properties. By providing materials researchers with the information they need to design better, the Materials Project aims to accelerate innovation in materials research.[copied from http://materialsproject.org/about] You will be asked to register to be granted free, full access.

  19. Composite material dosimeters

    DOEpatents

    Miller, Steven D.

    1996-01-01

    The present invention is a composite material containing a mix of dosimeter material powder and a polymer powder wherein the polymer is transparent to the photon emission of the dosimeter material powder. By mixing dosimeter material powder with polymer powder, less dosimeter material is needed compared to a monolithic dosimeter material chip. Interrogation is done with excitation by visible light.

  20. Method for forming materials

    DOEpatents

    Tolle, Charles R.; Clark, Denis E.; Smartt, Herschel B.; Miller, Karen S.

    2009-10-06

    A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.

  1. On the production of radium isotopes from uranium caused by irradiation with fast and decelerated neutrons⋆⋆⋆⋆⋆⋆

    NASA Astrophysics Data System (ADS)

    Hahn, O.; Strassmann, F.

    2016-10-01

    Received November 8, 1938; published November 18, 1938The article is a translation of the German original published as Hahn, O., Strassmann, F. Über die Entstehung von Radiumisotopen aus Uran durch Bestrahlen mit schnellen und verlangsamten Neutronen. Naturwissenschaften 46: 755-756, 1938.The current translation is by Georg Steinhauser, Leibniz Universität Hannover, Institut für Radioökologie und Strahlenschutz, Hannover, Germany; steinhauser@irs.uni-hannover.de. An attempt has been made to preserve Hahn's and Strassmann's writing style as much as possible. However, scientific German often uses the passive voice which is not always translated properly to English. Also the typically long German sentences sometimes had to be shortened for better English style. The references were converted to EPJH style, and the footnotes are numbered consecutively.

  2. Materials Informatics: Fast Track to New Materials

    SciTech Connect

    Ferris, Kim F.; Peurrung, Loni M.; Marder, James M.

    2007-01-01

    Current methods for new materials development focus on either deeper fundamental-level studies or generation of large quantities of data. The data challenge in materials science is not only the volume of data being generated by many independent investigators, but its heterogeneity and also its complexity that must be transformed, analyzed, correlated and communicated. Materials informatics addresses these issues. Materials informatics is an emerging information-based field combining computational, statistical, and mathematical approaches with materials sciences for accelerating discovery and development of new materials. Within the informatic framework, the various different forms of information form a system architecture, an iterative cycle for transforming data into knowledge.

  3. Ultrafast Pump-Probe Studies of the Light-Induced MIT and Recovery of Niobium Dioxide Thin Films

    NASA Astrophysics Data System (ADS)

    Beebe, Melissa; Klopf, J. Michael; Kittiwatanakul, Salinporn; Lu, Jiwei; Wolf, Stuart A.; Lukaszew, R. Alejandra

    Niobium dioxide (NbO2) is a highly correlated binary oxide that, like vanadium dioxide (VO2) , exhibits a first-order insulator-to-metal transition (IMT) at a material-dependent critical temperature, accompanied by a structural transformation from monoclinic to rutile. The nature of the IMT in VO2 has been discussed at length, while fewer studies have been carried out on NbO2. Previous studies show that the IMT can also be optically induced in VO2 on a sub-picosecond timescale; here, we present the first ultrafast pump-probe studies showing this optically-induced transition in NbO2 thin films and compare these results to similar ones carried out on VO2 thin films.

  4. L'ostéome ostéoïde de l'extrémité inférieur du radius: à propos d'un cas, localisation rare et revue de la littérature

    PubMed Central

    Abdelhafid, Derfoufi; Moncef, Erraji; Abdessamad, Kharraji; Najib, Abdeljaouad; Hicham, Yacoubi

    2016-01-01

    L'ostéome ostéoïde est une tumeur osseuse bénigne, mais douloureuse et dont le traitement consiste en l'exérèse chirurgicale totale. Nous rapportons, dans ce travail le cas d'une jeune patiente présentant un ostéome ostéoïde de l'extrémité inférieur du radius. PMID:27642387

  5. Transporting particulate material

    DOEpatents

    Aldred, Derek Leslie; Rader, Jeffrey A.; Saunders, Timothy W.

    2011-08-30

    A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

  6. Introductory Materials Laboratory.

    ERIC Educational Resources Information Center

    Ritter, John E., Jr.

    Described is an introductory materials science laboratory program which emphasizes crystal structure both on the atomistic and microscopic scale and the dependence of materials properties on structure. The content of this program is classified into four major areas: (1) materials science, (2) mechanical behavior of materials, (3) materials testing…

  7. Nanocrystalline ceramic materials

    DOEpatents

    Siegel, Richard W.; Nieman, G. William; Weertman, Julia R.

    1994-01-01

    A method for preparing a treated nanocrystalline metallic material. The method of preparation includes providing a starting nanocrystalline metallic material with a grain size less than about 35 nm, compacting the starting nanocrystalline metallic material in an inert atmosphere and annealing the compacted metallic material at a temperature less than about one-half the melting point of the metallic material.

  8. Material efficiency: providing material services with less material production.

    PubMed

    Allwood, Julian M; Ashby, Michael F; Gutowski, Timothy G; Worrell, Ernst

    2013-03-13

    Material efficiency, as discussed in this Meeting Issue, entails the pursuit of the technical strategies, business models, consumer preferences and policy instruments that would lead to a substantial reduction in the production of high-volume energy-intensive materials required to deliver human well-being. This paper, which introduces a Discussion Meeting Issue on the topic of material efficiency, aims to give an overview of current thinking on the topic, spanning environmental, engineering, economics, sociology and policy issues. The motivations for material efficiency include reducing energy demand, reducing the emissions and other environmental impacts of industry, and increasing national resource security. There are many technical strategies that might bring it about, and these could mainly be implemented today if preferred by customers or producers. However, current economic structures favour the substitution of material for labour, and consumer preferences for material consumption appear to continue even beyond the point at which increased consumption provides any increase in well-being. Therefore, policy will be required to stimulate material efficiency. A theoretically ideal policy measure, such as a carbon price, would internalize the externality of emissions associated with material production, and thus motivate change directly. However, implementation of such a measure has proved elusive, and instead the adjustment of existing government purchasing policies or existing regulations-- for instance to do with building design, planning or vehicle standards--is likely to have a more immediate effect.

  9. Material efficiency: providing material services with less material production

    PubMed Central

    Allwood, Julian M.; Ashby, Michael F.; Gutowski, Timothy G.; Worrell, Ernst

    2013-01-01

    Material efficiency, as discussed in this Meeting Issue, entails the pursuit of the technical strategies, business models, consumer preferences and policy instruments that would lead to a substantial reduction in the production of high-volume energy-intensive materials required to deliver human well-being. This paper, which introduces a Discussion Meeting Issue on the topic of material efficiency, aims to give an overview of current thinking on the topic, spanning environmental, engineering, economics, sociology and policy issues. The motivations for material efficiency include reducing energy demand, reducing the emissions and other environmental impacts of industry, and increasing national resource security. There are many technical strategies that might bring it about, and these could mainly be implemented today if preferred by customers or producers. However, current economic structures favour the substitution of material for labour, and consumer preferences for material consumption appear to continue even beyond the point at which increased consumption provides any increase in well-being. Therefore, policy will be required to stimulate material efficiency. A theoretically ideal policy measure, such as a carbon price, would internalize the externality of emissions associated with material production, and thus motivate change directly. However, implementation of such a measure has proved elusive, and instead the adjustment of existing government purchasing policies or existing regulations— for instance to do with building design, planning or vehicle standards—is likely to have a more immediate effect. PMID:23359746

  10. Thermoelectric materials and devices

    NASA Technical Reports Server (NTRS)

    Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor); Talcott, Noel A. (Inventor)

    2011-01-01

    New thermoelectric materials comprise highly [111]-oriented twinned group IV alloys on the basal plane of trigonal substrates, which exhibit a high thermoelectric figure of merit and good material performance, and devices made with these materials.

  11. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1982-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons and methods for making such materials. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  12. An integrated assessment modeling framework for uncertainty studies in global and regional climate change: the MIT IGSM-CAM (version 1.0)

    NASA Astrophysics Data System (ADS)

    Monier, E.; Scott, J. R.; Sokolov, A. P.; Forest, C. E.; Schlosser, C. A.

    2013-12-01

    This paper describes a computationally efficient framework for uncertainty studies in global and regional climate change. In this framework, the Massachusetts Institute of Technology (MIT) Integrated Global System Model (IGSM), an integrated assessment model that couples an Earth system model of intermediate complexity to a human activity model, is linked to the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). Since the MIT IGSM-CAM framework (version 1.0) incorporates a human activity model, it is possible to analyze uncertainties in emissions resulting from both uncertainties in the underlying socio-economic characteristics of the economic model and in the choice of climate-related policies. Another major feature is the flexibility to vary key climate parameters controlling the climate system response to changes in greenhouse gases and aerosols concentrations, e.g., climate sensitivity, ocean heat uptake rate, and strength of the aerosol forcing. The IGSM-CAM is not only able to realistically simulate the present-day mean climate and the observed trends at the global and continental scale, but it also simulates ENSO variability with realistic time scales, seasonality and patterns of SST anomalies, albeit with stronger magnitudes than observed. The IGSM-CAM shares the same general strengths and limitations as the Coupled Model Intercomparison Project Phase 3 (CMIP3) models in simulating present-day annual mean surface temperature and precipitation. Over land, the IGSM-CAM shows similar biases to the NCAR Community Climate System Model (CCSM) version 3, which shares the same atmospheric model. This study also presents 21st century simulations based on two emissions scenarios (unconstrained scenario and stabilization scenario at 660 ppm CO2-equivalent) similar to, respectively, the Representative Concentration Pathways RCP8.5 and RCP4.5 scenarios, and three sets of climate parameters. Results of the simulations with the chosen

  13. Grundsätze über die Anlagen neuer Sternwarten mit Beziehung auf die Sternwarte der Universität Göttingen. Von Georg Heinrich Borheck

    NASA Astrophysics Data System (ADS)

    Beuermann, Klaus; Borheck, Georg Heinrich

    Die Göttinger Sternwarte, Wirkungsstätte des berühmten Gelehrten Carl Friedrich Gauß, ist ein bedeutendes Baudenkmal. Im Jahre 2005 wird sie gemeinsam von der Georg-August-Universität und der Akademie der Wissenschaften zu Göttingen renoviert, um dann als repräsentatives Gebäude der Universität und Arbeitsstätte der Akademie zu dienen. Die Nutzung der historischen Räume für Ausstellungen macht diesen imposanten Bau erstmals der Öffentlichkeit zugänglich. Die Sternwarte war bei ihrer Errichtung vor 200 Jahren ein nach seinerzeit neuesten wissenschaftlichen Erkenntnissen konzipierter Bau, der die Universität Göttingen in eine der vordersten Stellen Europa rückte. Auch aufgrund ihrer Architektur ist sie ein großer Wurf des Göttinger Universitätsbaumeisters Georg Heinrich Borheck. Durch die Kriegswirren der Napoleonischen Zeit zerschlug sich Borhecks Versuch einer Publikation seiner Beschreibung des Baus der Göttinger Sternwarte 1805. Doch seine Schrift ist auch heute noch aktuell und wird mit diesem Band erstmals einer breiten Öffentlichkeit zugängig gemacht. Er zeigt die Grundsätze, nach denen damals öffentliche Bauten konzipiert wurden, erläutert die Bedeutung des Baus aus kunst- und wissenschaftshistorischer Sicht und informiert über die Pläne zur Restaurierung der Sternwarte in einem separaten Beitrag und im Geleitwort des Präsidenten der Georg-August Universität Prof. Dr. Dr. h. c. Kurt von Figura.

  14. Importing biological materials.

    PubMed

    Wolf, P

    2001-05-01

    This overview discusses critical issues regarding importing of restricted biological materials along with criteria for handling these materials. Guidelines for importing non-restricted biological materials are also covered. Recommendations are given for packaging biological materials for export, and finally, the necessary steps for obtaining an import permit application are outlined. PMID:18429071

  15. Coated ceramic breeder materials

    DOEpatents

    Tam, Shiu-Wing; Johnson, Carl E.

    1987-04-07

    A breeder material for use in a breeder blanket of a nuclear reactor is disclosed. The breeder material comprises a core material of lithium containing ceramic particles which has been coated with a neutron multiplier such as Be or BeO, which coating has a higher thermal conductivity than the core material.

  16. Coated ceramic breeder materials

    DOEpatents

    Tam, Shiu-Wing; Johnson, Carl E.

    1987-01-01

    A breeder material for use in a breeder blanket of a nuclear reactor is disclosed. The breeder material comprises a core material of lithium containing ceramic particles which has been coated with a neutron multiplier such as Be or BeO, which coating has a higher thermal conductivity than the core material.

  17. Biological materials by design.

    PubMed

    Qin, Zhao; Dimas, Leon; Adler, David; Bratzel, Graham; Buehler, Markus J

    2014-02-19

    In this topical review we discuss recent advances in the use of physical insight into the way biological materials function, to design novel engineered materials 'from scratch', or from the level of fundamental building blocks upwards and by using computational multiscale methods that link chemistry to material function. We present studies that connect advances in multiscale hierarchical material structuring with material synthesis and testing, review case studies of wood and other biological materials, and illustrate how engineered fiber composites and bulk materials are designed, modeled, and then synthesized and tested experimentally. The integration of experiment and simulation in multiscale design opens new avenues to explore the physics of materials from a fundamental perspective, and using complementary strengths from models and empirical techniques. Recent developments in this field illustrate a new paradigm by which complex material functionality is achieved through hierarchical structuring in spite of simple material constituents. PMID:24451343

  18. Materials Analysis and Modeling of Underfill Materials.

    SciTech Connect

    Wyatt, Nicholas B; Chambers, Robert S.

    2015-08-01

    The thermal-mechanical properties of three potential underfill candidate materials for PBGA applications are characterized and reported. Two of the materials are a formulations developed at Sandia for underfill applications while the third is a commercial product that utilizes a snap-cure chemistry to drastically reduce cure time. Viscoelastic models were calibrated and fit using the property data collected for one of the Sandia formulated materials. Along with the thermal-mechanical analyses performed, a series of simple bi-material strip tests were conducted to comparatively analyze the relative effects of cure and thermal shrinkage amongst the materials under consideration. Finally, current knowledge gaps as well as questions arising from the present study are identified and a path forward presented.

  19. Puncture detecting barrier materials

    DOEpatents

    Hermes, Robert E.; Ramsey, David R.; Stampfer, Joseph F.; Macdonald, John M.

    1998-01-01

    A method and apparatus for continuous real-time monitoring of the integrity of protective barrier materials, particularly protective barriers against toxic, radioactive and biologically hazardous materials has been developed. Conductivity, resistivity or capacitance between conductive layers in the multilayer protective materials is measured by using leads connected to electrically conductive layers in the protective barrier material. The measured conductivity, resistivity or capacitance significantly changes upon a physical breach of the protective barrier material.

  20. Nanocrystalline ceramic materials

    DOEpatents

    Siegel, R.W.; Nieman, G.W.; Weertman, J.R.

    1994-06-14

    A method is disclosed for preparing a treated nanocrystalline metallic material. The method of preparation includes providing a starting nanocrystalline metallic material with a grain size less than about 35 nm, compacting the starting nanocrystalline metallic material in an inert atmosphere and annealing the compacted metallic material at a temperature less than about one-half the melting point of the metallic material. 19 figs.

  1. Puncture detecting barrier materials

    DOEpatents

    Hermes, R.E.; Ramsey, D.R.; Stampfer, J.F.; Macdonald, J.M.

    1998-03-31

    A method and apparatus for continuous real-time monitoring of the integrity of protective barrier materials, particularly protective barriers against toxic, radioactive and biologically hazardous materials has been developed. Conductivity, resistivity or capacitance between conductive layers in the multilayer protective materials is measured by using leads connected to electrically conductive layers in the protective barrier material. The measured conductivity, resistivity or capacitance significantly changes upon a physical breach of the protective barrier material. 4 figs.

  2. Joining of dissimilar materials

    DOEpatents

    Tucker, Michael C; Lau, Grace Y; Jacobson, Craig P

    2012-10-16

    A method of joining dissimilar materials having different ductility, involves two principal steps: Decoration of the more ductile material's surface with particles of a less ductile material to produce a composite; and, sinter-bonding the composite produced to a joining member of a less ductile material. The joining method is suitable for joining dissimilar materials that are chemically inert towards each other (e.g., metal and ceramic), while resulting in a strong bond with a sharp interface between the two materials. The joining materials may differ greatly in form or particle size. The method is applicable to various types of materials including ceramic, metal, glass, glass-ceramic, polymer, cermet, semiconductor, etc., and the materials can be in various geometrical forms, such as powders, fibers, or bulk bodies (foil, wire, plate, etc.). Composites and devices with a decorated/sintered interface are also provided.

  3. Enhanced magnetocaloric effect material

    DOEpatents

    Lewis, Laura J. H.

    2006-07-18

    A magnetocaloric effect heterostructure having a core layer of a magnetostructural material with a giant magnetocaloric effect having a magnetic transition temperature equal to or greater than 150 K, and a constricting material layer coated on at least one surface of the magnetocaloric material core layer. The constricting material layer may enhance the magnetocaloric effect by restriction of volume changes of the core layer during application of a magnetic field to the heterostructure. A magnetocaloric effect heterostructure powder comprising a plurality of core particles of a magnetostructural material with a giant magnetocaloric effect having a magnetic transition temperature equal to or greater than 150 K, wherein each of the core particles is encapsulated within a coating of a constricting material is also disclosed. A method for enhancing the magnetocaloric effect within a giant magnetocaloric material including the step of coating a surface of the magnetocaloric material with a constricting material is disclosed.

  4. Martian surface materials

    NASA Technical Reports Server (NTRS)

    Moore, H. J.

    1991-01-01

    A semiquantitative appreciation for the physical properties of the Mars surface materials and their global variations can be gained from the Viking Lander and remote sensing observations. Analyses of Lander data yields estimates of the mechanical properties of the soil-like surface materials and best guess estimates can be made for the remote sensing signatures of the soil-like materials at the landing sites. Results show that significant thickness of powderlike surface materials with physical properties similar to drift material are present on Mars and probably pervasive in the Tharsis region. It also appears likely that soil-like materials similar to crusty to cloddy material are typical for Mars, and that soil-like material similar to blocky material are common on Mars.

  5. Orbital foamed material extruder

    NASA Technical Reports Server (NTRS)

    Tucker, Dennis S. (Inventor)

    2009-01-01

    This invention is a process for producing foamed material in space comprising the steps of: rotating the material to simulate the force of gravity; heating the rotating material until it is molten; extruding the rotating, molten material; injecting gas into the extruded, rotating, molten material to produce molten foamed material; allowing the molten foamed material to cool to below melting temperature to produce the foamed material. The surface of the extruded foam may be heated to above melting temperature and allowed to cool to below melting temperature. The extruded foam may also be cut to predetermined length. The starting material may be metal or glass. Heating may be accomplished by electrical heating elements or by solar heating.

  6. Smart Materials 1

    SciTech Connect

    Martin, Peter M.

    2003-06-01

    What is a smart material? What makes it smarter than a passive ''dumb'' material? The term ''smart material'' means a lot of things to a lot of people. ''Adaptronics'' is a word also commonly used for smart materials. One common definition is based on a technology paradigm: the integration of actuators, sensors, and controls with a material or structural component. The second broad definition is oriented more to biological systems: material systems that have intelligence and life features integrated in the microstructure of the material system to reduce mass energy and produce adaptive functionality. My basic simple-minded definition is: a ''smart material'' is a general term for a broad category of multifunctional materials for which a specific property (optical, mechanical, electronic, etc.) can be controllably modified.

  7. [Elastomeric impression materials].

    PubMed

    Anagnostopoulos, T; Tsokas, K

    1990-01-01

    A review of the literature on elastomeric impression materials, is presented in this paper. The article mentions the composition and the most important properties of the elastomeric impression materials used in dental practice. The clinical significance of these materials, physical and mechanical properties are also emphasized. In addition some new elastomeric impression materials with improved properties and a new (experimental) light-cured impression material, are mentioned. Another part of this article is the biocompatibility of these materials. In the end the great significance of handling is outlined. PMID:2130039

  8. Materials for breeding blankets

    SciTech Connect

    Mattas, R.F.; Billone, M.C.

    1995-09-01

    There are several candidate concepts for tritium breeding blankets that make use of a number of special materials. These materials can be classified as Primary Blanket Materials, which have the greatest influence in determining the overall design and performance, and Secondary Blanket Materials, which have key functions in the operation of the blanket but are less important in establishing the overall design and performance. The issues associated with the blanket materials are specified and several examples of materials performance are given. Critical data needs are identified.

  9. Materials All Around Us

    NASA Technical Reports Server (NTRS)

    Jacobs, James A.

    1996-01-01

    The purpose of this journal exercise is to determine the properties of the materials in the environment around us, and to relate these properties to the materials systems for which they are used. Students will develop a strong rationale for gaining knowledge of engineering materials. The journal entries will serve as a starting point classroom discussion. Along with the journal, students are required to bring samples to class of 'found' materials and products composed of materials systems. Students are encouraged to be materials observers.

  10. Insulated waterproof drainage material

    SciTech Connect

    Tarko, P.L.

    1988-03-15

    An insulative waterproof drainage material is described comprising: a sheet of rigid material having hills and valleys therein to define a core having opposed surfaces; permeable fabric material attached to one of the opposed surfaces; and a layer of thermally insulative material on the other of the opposed surfaces. The insulative material has first surface covering the hills and valleys and a second surface oppositely disposed from the first surface defining an outer surface. The outer surface is spaced a preselected distance D from the hills of the core. The pre-selected distance D define an insulative material thickness corresponding to a pre-selected thermal value.

  11. Materials science and engineering

    SciTech Connect

    Lesuer, D.R.

    1997-02-01

    During FY-96, work within the Materials Science and Engineering Thrust Area was focused on material modeling. Our motivation for this work is to develop the capability to study the structural response of materials as well as material processing. These capabilities have been applied to a broad range of problems, in support of many programs at Lawrence Livermore National Laboratory. These studies are described in (1) Strength and Fracture Toughness of Material Interfaces; (2) Damage Evolution in Fiber Composite Materials; (3) Flashlamp Envelope Optical Properties and Failure Analysis; (4) Synthesis and Processing of Nanocrystalline Hydroxyapatite; and (5) Room Temperature Creep Compliance of Bulk Kel-E.

  12. Nondestructive material characterization

    DOEpatents

    Deason, Vance A.; Johnson, John A.; Telschow, Kenneth L.

    1991-01-01

    A method and apparatus for nondestructive material characterization, such as identification of material flaws or defects, material thickness or uniformity and material properties such as acoustic velocity. The apparatus comprises a pulsed laser used to excite a piezoelectric (PZ) transducer, which sends acoustic waves through an acoustic coupling medium to the test material. The acoustic wave is absorbed and thereafter reflected by the test material, whereupon it impinges on the PZ transducer. The PZ transducer converts the acoustic wave to electrical impulses, which are conveyed to a monitor.

  13. Materials Test Branch

    NASA Technical Reports Server (NTRS)

    Gordon, Gail

    2012-01-01

    The Materials Test Branch resides at Marshall Space Flight Center's Materials and Processing laboratory and has a long history of supporting NASA programs from Mercury to the recently retired Space Shuttle. The Materials Test Branch supports its customers by supplying materials testing expertise in a wide range of applications. The Materials Test Branch is divided into three Teams, The Chemistry Team, The Tribology Team and the Mechanical Test Team. Our mission and goal is to provide world-class engineering excellence in materials testing with a special emphasis on customer service.

  14. Materials Discovery: Informatic Strategies for Optical Materials

    SciTech Connect

    Ferris, Kim F.; Webb-Robertson, Bobbie-Jo M.; Jones, Dumont M.

    2007-01-15

    Information-based materials discovery offers a structured method to evolve materials signatures based upon their physical properties, and to direct searches using performance-based criteria. In this current paper, we focus on the crystal structure aspects of an optical material and construct an information-based model to determine the proclivity of a particular AB composition to exhibit multiple crystal system behavior. Exploratory data methods used both supervised (support-vector machines) and unsupervised (disorder-reduction and principal-component) classification methods for structural signature development; revealing complementary valid signatures. Examination of the relative contributions of the materials chemistry descriptors within these signatures indicates a strong role for Mendeleev number chemistry which must be balanced against the cationic/anionic radius ratio and electronegativity differences of constituents within the unit cell.

  15. Materials science and engineering

    SciTech Connect

    Lesuer, D R

    1998-01-01

    During FY-97, work within the Materials Science and Engineering thrust area was focused on material modeling. Their motivation for this work is to develop the capability to study the structural response of materials as well as materials processing. These capabilities have been applied to a broad range of problems, which support many programs at Lawrence Livermore National Laboratory. Recent examples of structural response problems studied include material fracture (such as interface failure), damage in laser optics, the response of weapons components (such as high explosives) and the failure of composite materials. For materials processing, typical problems studied include metal forming, laser processing, casting, and heat treating. To improve our ability to model material behavior, much of the work involves developing new material models and failure models, as well as applying the codes to new problems. Most investigations involve experimental studies to gather basic information on material response and to validate codes or material models. Projects are inherently multi-disciplinary, involving several investigators with expertise in materials and mechanics. The thrust area studies for FY-97 are described in the following three articles: (1) Evolution of Anisotropic Yield Behavior; (2) Modeling of She Localization in Materials; and (3) Modeling of Casting Microstructures and Defects.

  16. EC Transmission Line Materials

    SciTech Connect

    Bigelow, Tim S

    2012-05-01

    The purpose of this document is to identify materials acceptable for use in the US ITER Project Office (USIPO)-supplied components for the ITER Electron cyclotron Heating and Current Drive (ECH&CD) transmission lines (TL), PBS-52. The source of material property information for design analysis shall be either the applicable structural code or the ITER Material Properties Handbook. In the case of conflict, the ITER Material Properties Handbook shall take precedence. Materials selection, and use, shall follow the guidelines established in the Materials Assessment Report (MAR). Materials exposed to vacuum shall conform to the ITER Vacuum Handbook. [Ref. 2] Commercial materials shall conform to the applicable standard (e.g., ASTM, JIS, DIN) for the definition of their grade, physical, chemical and electrical properties and related testing. All materials for which a suitable certification from the supplier is not available shall be tested to determine the relevant properties, as part of the procurement. A complete traceability of all the materials including welding materials shall be provided. Halogenated materials (example: insulating materials) shall be forbidden in areas served by the detritiation systems. Exceptions must be approved by the Tritium System and Safety Section Responsible Officers.

  17. Silicone azide fireproof material

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Finely powdered titanium oxide was added to silicone azide as the sintering agent to produce a nonflammable material. Mixing proportions, physical properties, and chemical composition of the fireproofing material are included.

  18. Lightweight Materials & Structures

    NASA Video Gallery

    The Lightweight Materials and Structures (LMS) project will mature high-payoff structures and materials technologies that have direct application to NASA’s future space exploration needs.One of the...

  19. Supplements to Textbook Materials.

    ERIC Educational Resources Information Center

    Holmes, Ken

    1994-01-01

    Describes the many kinds of materials that English teachers can draw upon to enrich and expand students' experiences with literature. Outlines ancillary materials used to supplement the study of William Shakespeare's "Julius Caesar." (HB)

  20. Renewable smart materials

    NASA Astrophysics Data System (ADS)

    Kim, Hyun Chan; Mun, Seongcheol; Ko, Hyun-U.; Zhai, Lindong; Kafy, Abdullahil; Kim, Jaehwan

    2016-07-01

    The use of renewable materials is essential in future technologies to harmonize with our living environment. Renewable materials can maintain our resources from the environment so as to overcome degradation of natural environmental services and diminished productivity. This paper reviews recent advancement of renewable materials for smart material applications, including wood, cellulose, chitin, lignin, and their sensors, actuators and energy storage applications. To further improve functionality of renewable materials, hybrid composites of inorganic functional materials are introduced by incorporating carbon nanotubes, titanium dioxide and tin oxide conducting polymers and ionic liquids. Since renewable materials have many advantages of biocompatible, sustainable, biodegradable, high mechanical strength and versatile modification behaviors, more research efforts need to be focused on the development of renewable smart materials.

  1. Materials processing in space

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The feasibility and possible advantages of processing materials in a nongravitational field are considered. Areas of investigation include biomedical applications, the processing of inorganic materials, and flight programs and funding.

  2. Materials modelling in London

    NASA Astrophysics Data System (ADS)

    Ciudad, David

    2016-04-01

    Angelos Michaelides, Professor in Theoretical Chemistry at University College London (UCL) and co-director of the Thomas Young Centre (TYC), explains to Nature Materials the challenges in materials modelling and the objectives of the TYC.

  3. Bibliography of AV Materials.

    ERIC Educational Resources Information Center

    Friedstein, Harriet, Ed.

    1981-01-01

    Lists commercially available audiovisual materials by subject area. Includes title, producer (addresses given), catalog number, format (film, filmstrip, cassette, slides), and prices. Subject areas include: elements; equilibrium; gases; laboratory techniques and experiments; general chemistry; introductory materials (including mathematics); and…

  4. Nanostructured composite reinforced material

    DOEpatents

    Seals, Roland D.; Ripley, Edward B.; Ludtka, Gerard M.

    2012-07-31

    A family of materials wherein nanostructures and/or nanotubes are incorporated into a multi-component material arrangement, such as a metallic or ceramic alloy or composite/aggregate, producing a new material or metallic/ceramic alloy. The new material has significantly increased strength, up to several thousands of times normal and perhaps substantially more, as well as significantly decreased weight. The new materials may be manufactured into a component where the nanostructure or nanostructure reinforcement is incorporated into the bulk and/or matrix material, or as a coating where the nanostructure or nanostructure reinforcement is incorporated into the coating or surface of a "normal" substrate material. The nanostructures are incorporated into the material structure either randomly or aligned, within grains, or along or across grain boundaries.

  5. Bridged graphite oxide materials

    NASA Technical Reports Server (NTRS)

    Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

    2010-01-01

    Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

  6. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1982-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  7. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1983-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  8. Improvisation: Teaching Materials.

    ERIC Educational Resources Information Center

    Kuzmich, John A., Jr.

    1980-01-01

    The past, present and future of music improvisation is discussed. Resources for piano, guitar, elementary general music materials, and electronic music materials are included, along with addresses of publishers. The emphasis is on jazz. (KC)

  9. Stabile Expression von Sulfotransferasen - allein oder in Kombination mit Cytochrom P450 - in Zelllinien für Mutagenitätsuntersuchungen

    NASA Astrophysics Data System (ADS)

    Pabel, Ulrike

    2003-10-01

    -dimethylaminoazobenzol; 0,1 µM für 2-Aminoanthracen; 10 µM für 2,4-Diaminotoluol). Die stärkste Aktivierung von 2-Acetylaminofluoren und 3′-Methyl-4-dimethylaminoazobenzol erfolgte in der Zelllinie, die CYP1A2 und SULT1A2 koexprimierte; die stärkste Aktivierung von 2,4-Diaminotoluol und 2-Aminoanthracen erfolgte in der Zelllinie, die CYP1A2 und SULT1A1 koexprimierte. Sowohl SULT1A1 als auch SULT1A2 sind im Menschen genetisch polymorph. Ein unterschiedlich starkes Aktivierungspotenzial der Alloenzyme könnte eine individuell unterschiedliche Suszeptibilität für die durch aAA ausgelöste Kanzerogenese bedingen. In HPRT-Mutationsuntersuchungen mit rekombinanten Zellen zeigten die allelischen Varianten der SULT1A2 starke Unterschiede in ihrem Aktivierungpotenzial. Nur in der Zelllinie, die das Alloenzym SULT1A2*1 mit CYP1A2 koexprimierte, wurde 2-Acetylaminofluoren zum Mutagen aktiviert. Zur Aktivierung von 3′-Methyl-4-dimethylaminoazobenzol waren jedoch sowohl das Alloenzym SULT1A2*1 als auch das Alloenzym SULT1A2*2 in der Lage. Die Alloenzyme der SULT1A1 zeigten ein ähnlich gutes Aktivierungspotenzial für aAA. In früheren Studien wurde gezeigt, dass die SULT1C1 der Ratte eine wichtige Rolle bei der Aktivierung der aAA in dieser Spezies spielt. Dahingegen war die humane SULT1C1 nicht in der Lage die untersuchten aAA zu aktivieren. Die Kenntnis solcher Spezieunterschiede könnte wichtig sein um unterschiedliche Organotropismen aAA in Menschen und Tiermodellen zu erklären, da SULT mit starker Gewebespezifität exprimiert werden und das Expressionsmuster für die einzelnen SULT-Formen in Menschen und Ratten sich stark unterscheidet. Aromatic amines and amides (aAA) represent a group of chemicals with great toxicological importance due to their wide distribution in the environment and their carcinogenic potency. The carcinogenicity of aAA is mediated by the mutagenic action of highly reactive metabolites. They are frequently formed by N-hydroxylation of the exocyclic

  10. Materials Genome Initiative Element

    NASA Technical Reports Server (NTRS)

    Vickers, John

    2015-01-01

    NASA is committed to developing new materials and manufacturing methods that can enable new missions with ever increasing mission demands. Typically, the development and certification of new materials and manufacturing methods in the aerospace industry has required more than 20 years of development time with a costly testing and certification program. To reduce the cost and time to mature these emerging technologies, NASA is developing computational materials tools to improve understanding of the material and guide the certification process.

  11. Smart materials and structures

    NASA Technical Reports Server (NTRS)

    Rogowski, Robert S.; Heyman, Joseph S.

    1993-01-01

    Embedded optical fibers allow not only the cure-monitoring and in-service lifetime measurements of composite materials, but the NDE of material damage and degradation with aging. The capabilities of such damage-detection systems have been extended to allow the quantitative determination of 2D strain in materials by several different methods, including the interferometric and the numerical. It remains to be seen, what effect the embedded fibers have on the strength of the 'smart' materials created through their incorporation.

  12. From Uhuru at CfA to SAS-3 at MIT: Looking for X-Ray Binaries in all the Right Places

    NASA Astrophysics Data System (ADS)

    Cominsky, Lynn R.

    2013-01-01

    My career in X-ray astronomy started almost accidentally, when in 1975 I was hired fresh out of college as a “data aide” for the Uhuru satellite, in Riccardo Giacconi’s group at the Harvard-Smithsonian Center for Astrophysics. Working first for Mel Ulmer, and later for Bill Forman and Christine Jones, I learned the fundamentals of data analysis, and helped produce the Fourth Uhuru catalog of X-ray sources (Forman et al. 1978), as well as studying transient X-ray sources (Cominsky et al. 1978). Christine was the first woman scientist I had ever met, and with her encouragement, I applied to graduate school to continue on in X-ray astronomy. Lured down the street to MIT by the chance to work on SAS-3, I eagerly learned how to operate the satellite from a control room in the Center for Space Research. The SAS-3 group was led by Prof. George Clark, and it was my good luck that he was around during the holiday break in January 1978 when everyone else in the group was at an AAS meeting in Hawaii. A source I recognized from my Uhuru work, 4U0115+63, had reappeared, and I knew that it was likely to be a pulsar. With the help of George and Project Scientist Bill Mayer, I managed to send the commands to stop SAS-3 and point at the source. The 3.6 second pulsations were so strong that they could be seen in the raw data! This discovery made the New York Times, as 4U0115+63 was the first transient x-ray source shown to be in a binary system (Cominsky et al. 1978, Rappaport et al. 1978). Another personal SAS-3 highlight included working on Prof. Walter Lewin’s “World-wide Burst Watch” - coordinated multi-wavelength observations of x-ray burst sources which led to the discoveries of slightly delayed but coincident optical bursts (Grindlay et al. 1978, McClintock et al. 1979). Although live operations of SAS-3 ended when it re-entered on April 9, 1979, many years of additional data analysis remained. And later, as a continuation of work I began in my Ph.D. Thesis on X

  13. Uran-Anreicherung mit Lasern

    NASA Astrophysics Data System (ADS)

    Meyer-Kretschmer, G.; Jetter, H.

    1983-01-01

    In uranium enrichment a substantial cost reduction seems to be possible with laser-based processes. Two different approaches are under investigation, the atomic-vapor process and the molecular process with UF6. The specific problems are discussed and the laser parameters are estimated. After intensive development activities in the past ten years the laser processes seem now to be ready for technical realization.

  14. Biomimetics and smart materials

    NASA Astrophysics Data System (ADS)

    Simmons, Wilbur C.

    1997-11-01

    Smart materials functions often mimic biological functions. Recent basic research at the U.S. Army Research Office has focused on biomimetics and meso-scale smart materials. Current ARO materials research interests and progress in these areas are reviewed for sensors, molecular recognition, signal transduction, structures and control functions.

  15. Biomimetics and smart materials

    NASA Astrophysics Data System (ADS)

    Simmons, Wilbur C.

    1997-11-01

    Smart Materials functions often mimic biological functions. Recent basic research at the US Army Research Office has focused on biomimetrics and meso-scale smart materials. Current ARO materials research interests and progress in these areas will be reviewed for sensors, molecular recognition, signal transduction, structures and control functions.

  16. Energy Education Materials Bibliography.

    ERIC Educational Resources Information Center

    Minnesota State Energy Agency, St. Paul.

    This is an annotated bibliography of selected energy education materials. The materials included in this document are indexed according to grade level and according to whether they are background materials or classroom activities. Each of the 100 items listed were evaluated and included into either the "A" list or the "B" list. The "A" list…

  17. Advanced Materials Technology

    NASA Technical Reports Server (NTRS)

    Blankenship, C. P. (Compiler); Teichman, L. A. (Compiler)

    1982-01-01

    Composites, polymer science, metallic materials (aluminum, titanium, and superalloys), materials processing technology, materials durability in the aerospace environment, ceramics, fatigue and fracture mechanics, tribology, and nondestructive evaluation (NDE) are discussed. Research and development activities are introduced to the nonaerospace industry. In order to provide a convenient means to help transfer aerospace technology to the commercial mainstream in a systematic manner.

  18. Creating Quality Media Materials.

    ERIC Educational Resources Information Center

    Hortin, John A.; Bailey, Gerald D.

    1982-01-01

    Innovation, imagination, and student creativity are key ingredients in creating quality media materials for the small school. Student-produced media materials, slides without a camera, personalized slide programs and copy work, self-made task cards, self-made overhead transparencies, graphic materials, and utilization of the mass media are some of…

  19. Bibliography of Citizenship Materials

    ERIC Educational Resources Information Center

    CASAS - Comprehensive Adult Student Assessment Systems (NJ1), 2008

    2008-01-01

    The 2008 CASAS "Bibliography of Citizenship Materials" lists available instructional resources for citizenship education. It focuses on materials appropriate for preparing people for the naturalization process and the standardized citizenship examination. Resources include textbooks, audio materials, software and Videos/DVDs. The bibliography also…

  20. Paramagnetic and Diamagnetic Materials

    ERIC Educational Resources Information Center

    Thompson, Frank

    2011-01-01

    Paramagnetic and diamagnetic materials are now generally known as the "Cinderella" materials of the magnetic world. However, susceptibility measurements made on these materials in the past have revealed many details about the molecular bonding and the atomic structure of the so-called "transition" elements. Indeed, the magnetic moment of neodymium…

  1. Hierarchical cellular materials

    SciTech Connect

    Gibson, L.J.

    1991-12-31

    In this paper a method for estimating the contributions of both the composite and the cellular microstructures to the overall material properties and the mechanical efficiency of natural cellular solids will be described. The method will be demonstrated by focusing on the Young`s modulus; similar techniques can be used for other material properties. The results suggest efficient microstructures for engineered cellular materials.

  2. Hierarchical cellular materials

    SciTech Connect

    Gibson, L.J.

    1991-01-01

    In this paper a method for estimating the contributions of both the composite and the cellular microstructures to the overall material properties and the mechanical efficiency of natural cellular solids will be described. The method will be demonstrated by focusing on the Young's modulus; similar techniques can be used for other material properties. The results suggest efficient microstructures for engineered cellular materials.

  3. Advanced neutron absorber materials

    DOEpatents

    Branagan, Daniel J.; Smolik, Galen R.

    2000-01-01

    A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

  4. Fusion reactor materials

    SciTech Connect

    none,

    1989-01-01

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  5. THE INSTRUCTIONAL MATERIALS CENTER.

    ERIC Educational Resources Information Center

    ARTZ, DELPHINE; AND OTHERS

    THIS BULLETIN PRESENTS RECOMMENDATIONS WITH REGARD TO PROGRAM, PERSONNEL, AND FACILITIES FOR AN INSTRUCTIONAL MATERIALS CENTER. IT INCLUDES UTILIZATION, MATERIALS, FACILITIES, ORGANIZATION AND LAYOUTS FOR AN INSTRUCTIONAL MATERIALS CENTER. CASE STUDIES AND EXAMPLES ARE PROVIDED FOR MAKING THE MAXIMUM POSSIBLE USAGE OF THE CENTER WITHIN BOTH THE…

  6. Materials for Space Exploration

    NASA Technical Reports Server (NTRS)

    Robertson, Luke B.; Williams, Martha

    2010-01-01

    Topics include a lab overview, testing and processing equipment, hemochromic hydrogen sensors, antimicrobial materials, wire system materials, CNT ink formulations, CNT ink dust screens, CNT ink printed circuitry, cryogenic materials development, fire and polymers, the importance of lighting, electric lighting systems, LED for plant growth, and carbon nanotube fiber filaments.

  7. Fast Neutron Albedo Calculations for a Concrete Shield with Different Curvatures

    NASA Astrophysics Data System (ADS)

    Sayed Ahmed, F. M.; Salama, M.

    The O5R Monte Carlo neutron transport Code had been used to calculate the neutron albedo for neutrons reflected from plane and curved concrete shields. The present calculations were performed to investigate the fast-neutron albedo in case of ordinary concrete shield, in order to perform comparative studies with the case of neutron reflection against a flat wall. The calculations were performed for three different neutron source energies of 1 MeV, 5 MeV and 15 MeV and at neutron incident angles of 5°, 30°, 45°, 60° and 90° and for surfaces with different curvatures (flat, 100, 50, 20 and 5 cm).The results obtained reveal that there will be an appreciable error on using the flat wall albedo value in the case of duct penetration calculations. The error was assumed to be due to the neglection of the curvature effect as well as to the improper choice of the neutron incident angle.Translated AbstractAlbedoberechnungen für schnelle Neutronen an einem Betonschild unterschiedlicher KrümmungDas O5R Monte Carlo Neutronentransport-Programm wurde benutzt, um die Albedo für Neutronen, reflektiert von ebenen oder gekrümmten Betonschilden, zu berechnen. Diese Berechnungen für die Albedo schneller Neutronen an gewöhnlichen Betonschilden wurden zum Vergleich mit ähnlichen Untersuchungen der Neutronenreflektion an flachen Wänden angestellt. Es wird bei drei verschiedenen Neutronenquellenenergien, 1 MeV, 5 MeV, und 15 MeV, Einfallswinkeln von 5°, 30°, 45°, 60° und 90° sowie für verschieden gekrümmte Oberflächen (flach, 100, 50, 20 und 5 cm) gerechnet.Diese Ergebnisse zeigen, daß die Verwendung von Albedowerten an flachen Wänden für den Fall von Durchlaßkanälen zu beträchtlichen Fehlern führt. Sie können sowohl der Vernachlässigung der Krümmung als auch der Wahl falscher Einfallswinkel zugeschrieben werden.

  8. Safer Aviation Materials Tested

    NASA Technical Reports Server (NTRS)

    Palaszewski, Bryan A.

    2001-01-01

    A series of thermally stable polymer samples were tested. These materials are called low heat release materials and are designed for aircraft interior decorative materials. The materials are designed to give off a minimum amount of noxious gases when heated, which increases the possibility that people can escape from a burning aircraft. New cabin materials have suitably low heat release so that fire does not spread, toxic chemicals are not given off, and the fire-emergency escape time for crew and passengers is lengthened. These low heat-release materials have a variety of advantages and applications: interiors for ground-based facilities, interiors of space vehicles, and many commercial fire-protection environments. A microscale combustion calorimeter at the Federal Aviation Administration's (FAA) Technical Center tested NASA Langley Research Center materials samples. The calorimeter is shown. A sharp, quantitative, and reproducible heat-release-rate peak is obtained in the microscale heat-release-rate test. The newly tested NASA materials significantly reduced the heat release capacity and total heat release. The thermal stability and flammability behavior of the samples was very good. The new materials demonstrated a factor of 4 reduction in total heat release over ULTEM (a currently used material). This information is provided in the following barchart. In other tests, the materials showed greater than a factor 9 reduction in heat-release capacity over ULTEM. The newly tested materials were developed for low dielectric constant, low color, and good solubility. A scale up of the material samples is needed to determine the repeatability of the performance in larger samples. Larger panels composed of the best candidate materials will be tested in a larger scale FAA Technical Center fire facility. The NASA Glenn Research Center, Langley (Jeff Hinkley), and the FAA Technical Center (Richard Lyon) cooperatively tested these materials for the Accident Mitigation

  9. Thermal Protection Materials Development

    NASA Technical Reports Server (NTRS)

    Selvaduray, Guna; Cox, Michael

    1998-01-01

    The main portion of this contract year was spent on the development of materials for high temperature applications. In particular, thermal protection materials were constantly tested and evaluated for thermal shock resistance, high-temperature dimensional stability, and tolerance to hostile environmental effects. The analytical laboratory at the Thermal Protection Materials Branch (TPMB), NASA-Ames played an integral part in the process of materials development of high temperature aerospace applications. The materials development focused mainly on the determination of physical and chemical characteristics of specimens from the various research programs.

  10. Tailored Porous Materials

    SciTech Connect

    BARTON,THOMAS J.; BULL,LUCY M.; KLEMPERER,WALTER G.; LOY,DOUGLAS A.; MCENANEY,BRIAN; MISONO,MAKOTO; MONSON,PETER A.; PEZ,GUIDO; SCHERER,GEORGE W.; VARTULI,JAMES C.; YAGHI,OMAR M.

    1999-11-09

    Tailoring of porous materials involves not only chemical synthetic techniques for tailoring microscopic properties such as pore size, pore shape, pore connectivity, and pore surface reactivity, but also materials processing techniques for tailoring the meso- and the macroscopic properties of bulk materials in the form of fibers, thin films and monoliths. These issues are addressed in the context of five specific classes of porous materials: oxide molecular sieves, porous coordination solids, porous carbons, sol-gel derived oxides, and porous heteropolyanion salts. Reviews of these specific areas are preceded by a presentation of background material and review of current theoretical approaches to adsorption phenomena. A concluding section outlines current research needs and opportunities.

  11. Dealloying and Dealloyed Materials

    NASA Astrophysics Data System (ADS)

    McCue, Ian; Benn, Ellen; Gaskey, Bernard; Erlebacher, Jonah

    2016-07-01

    A successful working model for nanoporosity evolution during dealloying was introduced 15 years ago. Since that time, the field has rapidly expanded, with research groups from across the world studying dealloying and dealloyed materials. Dealloying has grown into a rich field, with some groups focusing on fundamentals and mechanisms of dealloying, other groups creating new porous metals and alloys, and even more groups studying their properties. Dealloying was originally considered only in the context of corrosion, but now it is considered a facile self-organization technique to fabricate high-surface-area, bicontinuous nanoporous materials. Owing to their high interfacial area and the versatility of metallic materials, nanoporous metals have found application in catalysis, sensing, actuation, electrolytic and ultracapacitor materials, high-temperature templates/scaffolds, battery anodes, and radiation damage-tolerant materials. In this review, we discuss the fundamental materials principles underlying the formation of dealloyed materials and then look at two major applications: catalysis and nanomechanics.

  12. Materials processing in space

    NASA Technical Reports Server (NTRS)

    Waldron, R. D.; Criswell, D. R.

    1982-01-01

    Processing-refining of raw materials from extraterrestrial sources is detailed for a space materials handling facility. The discussion is constrained to those steps necessary to separate desired components from raw or altered input ores, semi-purified feedstocks, or process scrap and convert the material into elements, alloys, and consumables. The materials are regarded as originating from dead satellites and boosters, lunar materials, and asteroids. Strong attention will be given to recycling reagent substances to avoid the necessity of transporting replacements. It is assumed that since no aqueous processes exist on the moon, the distribution of minerals will be homogeneous. The processing-refining scenario will include hydrochemical, pyrochemical, electrochemical, and physical techniques selected for the output mass rate/unit plant mass ratio. Flow charts of the various materials processing operations which could be performed with lunar materials are provided, noting the necessity of delivering several alloying elements from the earth due to scarcities on the moon.

  13. Dealloying and Dealloyed Materials

    NASA Astrophysics Data System (ADS)

    McCue, Ian; Benn, Ellen; Gaskey, Bernard; Erlebacher, Jonah

    2016-07-01

    A successful working model for nanoporosity evolution during dealloying was introduced 15 years ago. Since that time, the field has rapidly expanded, with research groups from across the world studying dealloying and dealloyed materials. Dealloying has grown into a rich field, with some groups focusing on fundamentals and mechanisms of dealloying, other groups creating new porous metals and alloys, and even more groups studying their properties. Dealloying was originally considered only in the context of corrosion, but now it is considered a facile self-organization technique to fabricate high-surface-area, bicontinuous nanoporous materials. Owing to their high interfacial area and the versatility of metallic materials, nanoporous metals have found application in catalysis, sensing, actuation, electrolytic and ultracapacitor materials, high-temperature templates/scaffolds, battery anodes, and radiation damage–tolerant materials. In this review, we discuss the fundamental materials principles underlying the formation of dealloyed materials and then look at two major applications: catalysis and nanomechanics.

  14. Materials and structures

    NASA Technical Reports Server (NTRS)

    Saito, Theodore T.; Langenbeck, Sharon L.; Al-Jamily, Ghanim; Arnold, Joe; Barbee, Troy; Coulter, Dan; Dolgin, Ben; Fichter, Buck; George, Patricia; Gorenstein, Paul

    1992-01-01

    Materials and structures technology covers a wide range of technical areas. Some of the most pertinent issues for the Astrotech 21 missions include dimensionally stable structural materials, advanced composites, dielectric coatings, optical metallic coatings for low scattered light applications, low scattered light surfaces, deployable and inflatable structures (including optical), support structures in 0-g and 1-g environments, cryogenic optics, optical blacks, contamination hardened surfaces, radiation hardened glasses and crystals, mono-metallic telescopes and instruments, and materials characterization. Some specific examples include low coefficients of thermal expansion (CTE) structures (0.01 ppm/K), lightweight thermally stable mirror materials, thermally stable optical assemblies, high reliability/accuracy (1 micron) deployable structures, and characterization of nanometer level behavior of materials/structures for interferometry concepts. Large filled-aperture concepts will require materials with CTE's of 10(exp 9) at 80 K, anti-contamination coatings, deployable and erectable structures, composite materials with CTE's less than 0.01 ppm/K and thermal hysteresis, 0.001 ppm/K. Gravitational detection systems such as LAGOS will require rigid/deployable structures, dimensionally stable components, lightweight materials with low conductivity, and high stability optics. The Materials and Structures panel addressed these issues and the relevance of the Astrotech 21 mission requirements by dividing materials and structures technology into five categories. These categories, the necessary development, and applicable mission/program development phasing are summarized. For each of these areas, technology assessments were made and development plans were defined.

  15. Materials research for fusion

    NASA Astrophysics Data System (ADS)

    Knaster, J.; Moeslang, A.; Muroga, T.

    2016-05-01

    Fusion materials research started in the early 1970s following the observation of the degradation of irradiated materials used in the first commercial fission reactors. The technological challenges of fusion energy are intimately linked with the availability of suitable materials capable of reliably withstanding the extremely severe operational conditions of fusion reactors. Although fission and fusion materials exhibit common features, fusion materials research is broader. The harder mono-energetic spectrum associated with the deuterium-tritium fusion neutrons (14.1 MeV compared to <2 MeV on average for fission neutrons) releases significant amounts of hydrogen and helium as transmutation products that might lead to a (at present undetermined) degradation of structural materials after a few years of operation. Overcoming the historical lack of a fusion-relevant neutron source for materials testing is an essential pending step in fusion roadmaps. Structural materials development, together with research on functional materials capable of sustaining unprecedented power densities during plasma operation in a fusion reactor, have been the subject of decades of worldwide research efforts underpinning the present maturity of the fusion materials research programme.

  16. Materials and structures

    NASA Astrophysics Data System (ADS)

    Saito, Theodore T.; Langenbeck, Sharon L.; Al-Jamily, Ghanim; Arnold, Joe; Barbee, Troy; Coulter, Dan; Dolgin, Ben; Fichter, Buck; George, Patricia; Gorenstein, Paul

    1992-08-01

    Materials and structures technology covers a wide range of technical areas. Some of the most pertinent issues for the Astrotech 21 missions include dimensionally stable structural materials, advanced composites, dielectric coatings, optical metallic coatings for low scattered light applications, low scattered light surfaces, deployable and inflatable structures (including optical), support structures in 0-g and 1-g environments, cryogenic optics, optical blacks, contamination hardened surfaces, radiation hardened glasses and crystals, mono-metallic telescopes and instruments, and materials characterization. Some specific examples include low coefficients of thermal expansion (CTE) structures (0.01 ppm/K), lightweight thermally stable mirror materials, thermally stable optical assemblies, high reliability/accuracy (1 micron) deployable structures, and characterization of nanometer level behavior of materials/structures for interferometry concepts. Large filled-aperture concepts will require materials with CTE's of 10(exp 9) at 80 K, anti-contamination coatings, deployable and erectable structures, composite materials with CTE's less than 0.01 ppm/K and thermal hysteresis, 0.001 ppm/K. Gravitational detection systems such as LAGOS will require rigid/deployable structures, dimensionally stable components, lightweight materials with low conductivity, and high stability optics. The Materials and Structures panel addressed these issues and the relevance of the Astrotech 21 mission requirements by dividing materials and structures technology into five categories. These categories, the necessary development, and applicable mission/program development phasing are summarized. For each of these areas, technology assessments were made and development plans were defined.

  17. Engineering Living Functional Materials

    PubMed Central

    2016-01-01

    Natural materials, such as bone, integrate living cells composed of organic molecules together with inorganic components. This enables combinations of functionalities, such as mechanical strength and the ability to regenerate and remodel, which are not present in existing synthetic materials. Taking a cue from nature, we propose that engineered ‘living functional materials’ and ‘living materials synthesis platforms’ that incorporate both living systems and inorganic components could transform the performance and the manufacturing of materials. As a proof-of-concept, we recently demonstrated that synthetic gene circuits in Escherichia coli enabled biofilms to be both a functional material in its own right and a materials-synthesis platform. To demonstrate the former, we engineered E. coli biofilms into a chemical-inducer-responsive electrical switch. To demonstrate the latter, we engineered E. coli biofilms to dynamically organize biotic-abiotic materials across multiple length scales, template gold nanorods, gold nanowires, and metal/semiconductor heterostructures, and synthesize semiconductor nanoparticles (Chen, A. Y. et al. (2014) Synthesis and patterning of tunable multiscale materials with engineered cells. Nat. Mater.13, 515–523.). Thus, tools from synthetic biology, such as those for artificial gene regulation, can be used to engineer the spatiotemporal characteristics of living systems and to interface living systems with inorganic materials. Such hybrids can possess novel properties enabled by living cells while retaining desirable functionalities of inorganic systems. These systems, as living functional materials and as living materials foundries, would provide a radically different paradigm of materials performance and synthesis–materials possessing multifunctional, self-healing, adaptable, and evolvable properties that are created and organized in a distributed, bottom-up, autonomously assembled, and environmentally sustainable manner. PMID

  18. Characterization of Nanophase Materials

    NASA Astrophysics Data System (ADS)

    Wang, Zhong Lin

    2000-01-01

    Engineering of nanophase materials and devices is of vital interest in electronics, semiconductors and optics, catalysis, ceramics and magnetism. Research associated with nanoparticles has widely spread and diffused into every field of scientific research, forming a trend of nanocrystal engineered materials. The unique properties of nanophase materials are entirely determined by their atomic scale structures, particularly the structures of interfaces and surfaces. Development of nanotechnology involves several steps, of which characterization of nanoparticles is indespensable to understand the behavior and properties of nanoparticles, aiming at implementing nanotechnolgy, controlling their behavior and designing new nanomaterials systems with super performance. The book will focus on structural and property characterization of nanocrystals and their assemblies, with an emphasis on basic physical approach, detailed techniques, data interpretation and applications. Intended readers of this comprehensive reference work are advanced graduate students and researchers in the field, who are specialized in materials chemistry, materials physics and materials science.

  19. Benzimidazole Based Aerogel Materials

    NASA Technical Reports Server (NTRS)

    Rhine, Wendell E. (Inventor); Mihalcik, David (Inventor)

    2016-01-01

    The present invention provides aerogel materials based on imidazoles and polyimidazoles. The polyimidazole based aerogel materials can be thermally stable up to 500 C or more, and can be carbonized to produce a carbon aerogel having a char yield of 60% or more, specifically 70% or more. The present invention also provides methods of producing polyimidazole based aerogel materials by reacting at least one monomer in a suitable solvent to form a polybenzimidazole gel precursor solution, casting the polybenzimidazole gel precursor solution into a fiber reinforcement phase, allowing the at least one gel precursor in the precursor solution to transition into a gel material, and drying the gel materials to remove at least a portion of the solvent, to obtain an polybenzimidazole-based aerogel material.

  20. Ultrasonic nondestructive materials characterization

    NASA Technical Reports Server (NTRS)

    Green, R. E., Jr.

    1986-01-01

    A brief review of ultrasonic wave propagation in solid materials is presented with consideration of the altered behavior in anisotropic and nonlinear elastic materials in comparison with isotropic and linear elastic materials. Some experimental results are described in which ultrasonic velocity and attenuation measurements give insight into materials microstructure and associated mechanical properties. Recent developments with laser beam non-contact generation and detection of ultrasound are presented. The results of several years of experimental measurements using high-power ultrasound are discussed, which provide substantial evidence of the inability of presently accepted theories to fully explain the interaction of ultrasound with solid materials. Finally, a special synchrotron X-ray topographic system is described which affords the possibility of observing direct interaction of ultrasonic waves with the microstructural features of real crystalline solid materials for the first time.

  1. NUCLEAR FUEL MATERIAL

    DOEpatents

    Goeddel, W.V.

    1962-06-26

    An improved method is given for making the carbides of nuclear fuel material. The metal of the fuel material, which may be a fissile and/or fertile material, is transformed into a silicide, after which the silicide is comminuted to the desired particle size. This silicide is then carburized at an elevated temperature, either above or below the melting point of the silicide, to produce an intimate mixture of the carbide of the fuel material and the carbide of silicon. This mixture of the fuel material carbide and the silicon carbide is relatively stable in the presence of moisture and does not exhibit the highly reactive surface condition which is observed with fuel material carbides made by most other known methods. (AEC)

  2. Femtosecond laser materials processing

    SciTech Connect

    Stuart, B. C., LLNL

    1998-06-02

    Femtosecond lasers enable materials processing of most any material with extremely high precision and negligible shock or thermal loading to the surrounding area Applications ranging from drilling teeth to cutting explosives to making high-aspect ratio cuts in metals with no heat-affected zone are made possible by this technology For material removal at reasonable rates, we developed a fully computer-controlled 15-Watt average power, 100-fs laser machining system.

  3. Feeder for particulate material

    SciTech Connect

    Christofer, D.E.; Stock, A.J.

    1981-03-24

    Feeder apparatus for feeding at a controlled variable rate particulate solid material, such as coal, from a supply conduit located above a gravimetric feeder to a discharge chute located below the feeder. The particulate material flows to the feeder from the supply conduit along a path having a generally vertical center line and the discharge chute provides a flow path having a generally vertical center line closely laterally spaced relative to the center line of flow to the feeder. The feeder apparatus has a horizontally extending housing with an upwardly facing inlet through which the material flows to the feeder and a downwardly facing outlet forming part of the discharge chute through which the material flows from the feeder. Within the housing is a main feeder conveyor including an endless belt with a generally horizontal span adapted to receive at one end the particulate material flowing to the feeder and to convey in a layer a measured quantity of material a horizontal distance across weighing means to an exit zone at the opposite end of the belt, the horizontal distance being substantially greater than the spacing between the center lines of flow to the feeder and through such discharge chute. Associated with the main feeder conveyor is a gravimetric control system for controlling the amount of material deposited on the belt. Particulate material that drops off the main conveyor belt at the exit zone is received on a return belt conveyor and carried in a reverse direction a sufficient distance to bring the material to the discharge chute. Cooperation between the main feeder conveyor and the return conveyor permits gravimetric feeding of particulate material to the discharge chute that is closely laterally spaced to the flow path of material to the main conveyor by a distance that is substantially less than the length of travel of the material on the main conveyor.

  4. Femtosecond laser materials processing

    SciTech Connect

    Stuart, B

    1998-08-05

    Femtosecond lasers enable materials processing of most any material with extremely high precision and negligible shock or thermal loading to the surrounding area. Applications ranging from drilling teeth to cutting explosives to precision cuts in composites are possible by using this technology. For material removal at reasonable rates, we have developed a fully computer-controlled 15-Watt average power, 100-fs laser machining system.

  5. Infrared fiber optic materials

    NASA Technical Reports Server (NTRS)

    Feigelson, Robert S.

    1987-01-01

    The development of IR fiber optics for use in astronomical and other space applications is summarized. Candidate materials were sought for use in the 1 to 200 micron and the 200 to 1000 micron wavelength range. Synthesis and optical characterization were carried out on several of these materials in bulk form. And the fabrication of a few materials in single crystal fiber optic form were studied.

  6. ANS materials databook

    SciTech Connect

    Marchbanks, M.F.

    1995-08-01

    Technical development in the Advanced Neutron Source (ANS) project is dynamic, and a continuously updated information source is necessary to provide readily usable materials data to the designer, analyst, and materials engineer. The Advanced Neutron Source Materials Databook (AMBK) is being developed as a part of the Advanced Neutron Source Materials Information System (AMIS). Its purpose is to provide urgently needed data on a quick-turnaround support basis for those design applications whose schedules demand immediate estimates of material properties. In addition to the need for quick materials information, there is a need for consistent application of data throughout the ANS Program, especially where only limited data exist. The AMBK is being developed to fill this need as well. It is the forerunner to the Advanced Neutron Source Materials Handbook (AMHB). The AMHB, as reviewed and approved by the ANS review process, will serve as a common authoritative source of materials data in support of the ANS Project. It will furnish documented evidence of the materials data used in the design and construction of the ANS system and will serve as a quality record during any review process whose objective is to establish the safety level of the ANS complex. The information in the AMBK and AMHB is also provided in electronic form in a dial-up computer database known as the ANS Materials Database (AMDB). A single consensus source of materials information prepared and used by all national program participants has several advantages. Overlapping requirements and data needs of various sub-projects and subcontractors can be met by a single document which is continuously revised. Preliminary and final safety analysis reports, stress analysis reports, equipment specifications, materials service reports, and many other project-related documents can be substantially reduced in size and scope by appropriate reference to a single data source.

  7. Multilayer Insulation Material Guidelines

    NASA Technical Reports Server (NTRS)

    Finckenor, M. M.; Dooling, D.

    1999-01-01

    Multilayer Insulation Material Guidelines provides data on multilayer insulation materials used by previous spacecraft such as Spacelab and the Long-Duration Exposure Facility and outlines other concerns. The data presented in the document are presented for information only. They can be used as guidelines for multilayer insulation design for future spacecraft provided the thermal requirements of each new design and the environmental effects on these materials are taken into account.

  8. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  9. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2010-07-13

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  10. Materials for Slack Diaphragms

    NASA Technical Reports Server (NTRS)

    Puschmann, Traute

    1940-01-01

    This report deals with systematic experiments carried out on five diaphragm materials with different pretreatment, for the purpose of ascertaining the suitability of such materials for slack diaphragms. The relationship of deflection and load, temperature and moisture, was recorded. Of the explored materials, synthetic leather, balloon cloth, goldbeaters skin, Igelit and Buna, synthetic leather treated with castor oil is the most suitable material for the small pressure range required. Balloon cloth is nearly as good, while goldbeaters skin, Igelit and Buna were found to be below the required standards.

  11. Assessment of biobased materials

    SciTech Connect

    Chum, H.L.

    1989-12-01

    Biobased materials are polymers derived from renewable resources by chemical or combined chemical and mechanical methods, or produced directly in biological processes. Combinations of renewable and conventional fossil-fuel-derived plastics are also biobased materials. This assessment reviews materials from renewable resources and their properties including major biopolymers produced by plants and selected animal sources. Examples discussed are wood, its polymeric components such as cellulose and lignin, related polymers such as chitin, other carbohydrate polymers such as starch, which when combined with plastics can impart environmental degradability to the resulting material. The conventional role of inexpensive wood flour as a filler is reviewed as well as the future research necessary to bring these materials into a higher value use as a reinforcing material for composites. Automotive, building, and packaging materials applications are considered. Bioproduction of materials is reviewed for selected polymers such as cellulose, other plant cell wall polymers, and proteins, with emphasis on silk and wool. These materials can be produced with specific properties such as biodegradability (e.g., polyhydroxybutyrate and valerate copolymers, polylactide polymers) or specific mechanical properties.

  12. Fluorinated elastomeric materials

    DOEpatents

    Lagow, Richard J.; Dumitru, Earl T.

    1990-02-13

    This invention relates to a method of making perfluorinated elastomeric materials, and to materials made by such methods. In the full synthetic scheme, a partially fluorinated polymeric compound, with moieties to prevent crystallization, is created. It is then crosslinked to a desired degree, then perfluorinated. Various intermediate materials, such as partially fluorinated crosslinked polymers, have useful properties, and are or may become commercially available. One embodiment of this invention therefore relates to perfluorination of a selected partially fluorinated, crosslinked material, which is one step of the full synthetic scheme.

  13. Fluorinated elastomeric materials

    DOEpatents

    Lagow, Richard J.; Dumitru, Earl T.

    1986-11-04

    This invention relates to a method of making perfluorinated elastomeric materials, and to materials made by such methods. In the full synthetic scheme, a partially fluorinated polymeric compound, with moieties to prevent crystallization, is created. It is then crosslinked to a desired degree, then perfluorinated. Various intermediate materials, such as partially fluorinated crosslinked polymers, have useful properties, and are or may become commercially available. One embodiment of this invention therefore relates to perfluorination of a selected partially fluorinated, crosslinked material, which is one step of the full synthetic scheme.

  14. Materials Science Laboratory

    NASA Technical Reports Server (NTRS)

    Jackson, Dionne

    2005-01-01

    The NASA Materials Science Laboratory (MSL) provides science and engineering services to NASA and Contractor customers at KSC, including those working for the Space Shuttle. International Space Station. and Launch Services Programs. These services include: (1) Independent/unbiased failure analysis (2) Support to Accident/Mishap Investigation Boards (3) Materials testing and evaluation (4) Materials and Processes (M&P) engineering consultation (5) Metrology (6) Chemical analysis (including ID of unknown materials) (7) Mechanical design and fabrication We provide unique solutions to unusual and urgent problems associated with aerospace flight hardware, ground support equipment and related facilities.

  15. Flexible Material Systems Testing

    NASA Technical Reports Server (NTRS)

    Lin, John K.; Shook, Lauren S.; Ware, Joanne S.; Welch, Joseph V.

    2010-01-01

    An experimental program has been undertaken to better characterize the stress-strain characteristics of flexible material systems to support a NASA ground test program for inflatable decelerator material technology. A goal of the current study is to investigate experimental methods for the characterization of coated woven material stiffness. This type of experimental mechanics data would eventually be used to define the material inputs of fluid-structure interaction simulation models. The test methodologies chosen for this stress-strain characterization are presented along with the experimental results.

  16. Mechanics of materials model

    NASA Technical Reports Server (NTRS)

    Meister, Jeffrey P.

    1987-01-01

    The Mechanics of Materials Model (MOMM) is a three-dimensional inelastic structural analysis code for use as an early design stage tool for hot section components. MOMM is a stiffness method finite element code that uses a network of beams to characterize component behavior. The MOMM contains three material models to account for inelastic material behavior. These include the simplified material model, which assumes a bilinear stress-strain response; the state-of-the-art model, which utilizes the classical elastic-plastic-creep strain decomposition; and Walker's viscoplastic model, which accounts for the interaction between creep and plasticity that occurs under cyclic loading conditions.

  17. The Materials Genome Project

    NASA Astrophysics Data System (ADS)

    Aourag, H.

    2008-09-01

    In the past, the search for new and improved materials was characterized mostly by the use of empirical, trial- and-error methods. This picture of materials science has been changing as the knowledge and understanding of fundamental processes governing a material's properties and performance (namely, composition, structure, history, and environment) have increased. In a number of cases, it is now possible to predict a material's properties before it has even been manufactured thus greatly reducing the time spent on testing and development. The objective of modern materials science is to tailor a material (starting with its chemical composition, constituent phases, and microstructure) in order to obtain a desired set of properties suitable for a given application. In the short term, the traditional "empirical" methods for developing new materials will be complemented to a greater degree by theoretical predictions. In some areas, computer simulation is already used by industry to weed out costly or improbable synthesis routes. Can novel materials with optimized properties be designed by computers? Advances in modelling methods at the atomic level coupled with rapid increases in computer capabilities over the last decade have led scientists to answer this question with a resounding "yes'. The ability to design new materials from quantum mechanical principles with computers is currently one of the fastest growing and most exciting areas of theoretical research in the world. The methods allow scientists to evaluate and prescreen new materials "in silico" (in vitro), rather than through time consuming experimentation. The Materials Genome Project is to pursue the theory of large scale modeling as well as powerful methods to construct new materials, with optimized properties. Indeed, it is the intimate synergy between our ability to predict accurately from quantum theory how atoms can be assembled to form new materials and our capacity to synthesize novel materials atom

  18. Thermoelectric materials having porosity

    SciTech Connect

    Heremans, Joseph P.; Jaworski, Christopher M.; Jovovic, Vladimir; Harris, Fred

    2014-08-05

    A thermoelectric material and a method of making a thermoelectric material are provided. In certain embodiments, the thermoelectric material comprises at least 10 volume percent porosity. In some embodiments, the thermoelectric material has a zT greater than about 1.2 at a temperature of about 375 K. In some embodiments, the thermoelectric material comprises a topological thermoelectric material. In some embodiments, the thermoelectric material comprises a general composition of (Bi.sub.1-xSb.sub.x).sub.u(Te.sub.1-ySe.sub.y).sub.w, wherein 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, 1.8.ltoreq.u.ltoreq.2.2, 2.8.ltoreq.w.ltoreq.3.2. In further embodiments, the thermoelectric material includes a compound having at least one group IV element and at least one group VI element. In certain embodiments, the method includes providing a powder comprising a thermoelectric composition, pressing the powder, and sintering the powder to form the thermoelectric material.

  19. Material for radioactive protection

    DOEpatents

    Taylor, R.S.; Boyer, N.W.

    A boron containing burn resistant, low-level radiation protection material useful, for example, as a liner for radioactive waste disposal and storage, a component for neutron absorber, and a shield for a neutron source is described. The material is basically composed of borax in the range of 25 to 50%, coal tar in the range of 25 to 37.5%, with the remainder being an epoxy resin mix. A preferred composition is 50% borax, 25% coal tar and 25% epoxy resin. The material is not susceptible to burning and is about 1/5 the cost of existing radiation protection material utilized in similar applications.

  20. [Materials for construction sector].

    PubMed

    Macchia, C

    2012-01-01

    The construction sector is characterized by high complexity due to several factors. There are a lot of processes within the building sites and they need the use of different materials with the help of appropriate technologies. Traditional materials have evolved and diversified, meanwhile new products and materials appeared and still appear, offering services which meet user needs, but that often involve risks to the health of workers. Research in the field of materials, promoted and carried out at various levels, has led to interesting results, encoded in the form of rules and laws.

  1. LDEF materials overview

    NASA Technical Reports Server (NTRS)

    Stein, Bland A.

    1993-01-01

    The flight and retrieval of the National Aeronautics and Space Administration's Long Duration Exposure Facility (LDEF) provided an opportunity for the study of the low-Earth orbit (LEO) environment and long-duration space environmental effects (SEE) on materials that is unparalleled in the history of the U.S. Space Program. The 5-year, 9-month flight of LDEF greatly enhanced the potential value of all materials on LDEF to the international SEE community, compared to that of the original 1-year flight plan. The remarkable flight attitude stability of LDEF enables specific analyses of individual and combined effects of LEO environmental parameters on identical materials on the same space vehicle. NASA recognized this potential by forming the LDEF Space Environmental Effects on Materials Special Investigation Group (MSIG) to address the greatly expanded materials and LEO space environment analysis opportunities available in the LDEF structure, experiment trays, and corollary measurements so that the combined value of all LDEF materials data to current and future space missions will be addressed and documented. An overview of the interim LDEF materials findings of the principal investigators and the Materials Special Investigation Group is provided. These revelations are based on observations of LEO environmental effects on materials made in space during LDEF retrieval and during LDEF tray deintegration at the Kennedy Space Center, and on findings of approximately 1.5 years of laboratory analyses of LDEF materials by the LDEF materials scientists. These findings were extensively reviewed and discussed at the MSIG-sponsored LDEF Materials Workshop '91. The results are presented in a format that categorizes the revelations as 'clear findings' or 'obscure preliminary findings' (and progress toward their resolution), plus resultant needs for new space materials developments and ground simulation testing/analytical modeling, in seven categories: materials

  2. Biogenic Impact on Materials

    NASA Astrophysics Data System (ADS)

    Stephan, Ina; Askew, Peter D.; Gorbushina, Anna A.; Grinda, Manfred; Hertel, Horst; Krumbein, Wolfgang E.; Müller, Rolf-Joachim; Pantke, Michael; Plarre, Rüdiger (Rudy); Schmitt, Guenter; Schwibbert, Karin

    Materials as constituents of products or components of technical systems rarely exist in isolation and many must cope with exposure in the natural world. This chapter describes methods that simulate how a material is influenced through contact with living systems such as microorganisms and arthropods. Both unwanted and desirable interactions are considered. This biogenic impact on materials is intimately associated with the environment to which the material is exposed (Materials-Environment Interaction, Chap. 15). Factors such as moisture, temperature and availability of food sources all have a significant influence on biological systems. Corrosion (Chap. 12) and wear (Chap. 13) can also be induced or enhanced in the presence of microorganisms. Section 14.1 introduces the categories between desired (biodegradation) and undesired (biodeterioration) biological effects on materials. It also introduces the role of biocides for the protection of materials. Section 14.2 describes the testing of wood as a building material especially against microorganisms and insects. Section 14.3 characterizes the test methodologies for two other groups of organic materials, namely polymers (Sect. 14.3.1) and paper and textiles (Sect. 14.3.2). Section 14.4 deals with the susceptibility of inorganic materials such as metals (Sect. 14.4.1), concrete (Sect. 14.4.2) and ceramics (Sect. 14.4.3) to biogenic impact. Section 14.5 treats the testing methodology concerned with the performance of coatings and coating materials. In many of these tests specific strains of organisms are employed. It is vital that these strains retain their ability to utilize/attack the substrate from which they were isolated, even when kept for many years in the laboratory. Section 14.6 therefore considers the importance of maintaining robust and representative test organisms that are as capable of utilizing a substrate as their counterparts in nature such that realistic predictions of performance can be made.

  3. Nanoprobes, nanostructured materials and solid state materials

    NASA Astrophysics Data System (ADS)

    Yin, Houping

    2005-07-01

    Novel templates have been developed to prepare nanostructured porous materials through nonsurfactant templated pathway. And new applications of these materials, such as drug delivery and molecular imprinting, have been explored. The relationship between template content and pore structure has been investigated. The composition and pore structures were studied in detail using IR, TGA, SEM, TEM, BET and XRD. The obtained mesoporous materials have tunable diameters in the range of 2--12 nm. Due to the many advantages of this nonsurfactant templated pathway, such as environment friendly and biocompatibility, controlled release of antibiotics in the nanoporous materials were studied. The in vitro release properties were found to depend on the silica structures which were well tuned by varying the template content. A controlled long-term release pattern of vancomycin was achieved when the template content was 30 wt% or lower. Nanoscale electrochemical probes with dimensions as small as 50 nm in diameter and 1--2 mum in length were fabricated using electron beam deposition on the apex of conventional micron size electrodes. The electroactive region was limited to the extreme tip of the nanoprobe by coating with an insulating polymer and re-opening of the coating at the extreme tip. The novel nanoelectrodes thus prepared were employed to probe neurons in mouse brain slice and the results suggest that the nanoprobes were capable of recording neuronal excitatory postsynaptic potential signals. Interesting solid state chemistry was found in oxygenated iron phthalocyanine. Their Mossbauer spectra show the formation of four oxygenated species apart from the unoxygenated parent compound. The oxygen-bridged compounds formed in the solid matrix bear no resemblance to the one formed by solution chemistry. Tentative assignment of species has been made with the help of Mossbauer and IR spectroscopy. An effort to modify aniline trimer for potential nanoelectronics applications and to

  4. Packaging Materials Properties Data

    SciTech Connect

    Leduc, D.

    1991-10-30

    Several energy absorbing materials are used in nuclear weapons component shipping containers recently designed for the Y-12 Plant Program Management Packaging Group. As a part of the independent review procedure leading to Certificates of Compliance, the U.S. Department of Energy Technical Safety Review Panels requested compression versus deflection . data on these materials. This report is a compilation of that data.

  5. Packaging materials properties data

    SciTech Connect

    Walker, M.S.

    1991-01-01

    Several energy absorbing materials are used in nuclear weapons component shipping containers recently designed for the Y-12 Plant Program Management Packaging Group. As a part of the independent review procedure leading to Certificates of Compliance, the US Department of Energy Technical Safety Review Panels requested compression versus deflection data on these materials. This report is a compilation of that data.

  6. Hydrocarbonaceous material upgrading method

    SciTech Connect

    Brecher, Lee E.; Mones, Charles G.; Guffey, Frank D.

    2015-06-02

    A hydrocarbonaceous material upgrading method may involve a novel combination of heating, vaporizing and chemically reacting hydrocarbonaceous feedstock that is substantially unpumpable at pipeline conditions, and condensation of vapors yielded thereby, in order to upgrade that feedstock to a hydrocarbonaceous material condensate that meets crude oil pipeline specification.

  7. MULTISCALE PHENOMENA IN MATERIALS

    SciTech Connect

    A. BISHOP

    2000-09-01

    This project developed and supported a technology base in nonequilibrium phenomena underpinning fundamental issues in condensed matter and materials science, and applied this technology to selected problems. In this way the increasingly sophisticated synthesis and characterization available for classes of complex electronic and structural materials provided a testbed for nonlinear science, while nonlinear and nonequilibrium techniques helped advance our understanding of the scientific principles underlying the control of material microstructure, their evolution, fundamental to macroscopic functionalities. The project focused on overlapping areas of emerging thrusts and programs in the Los Alamos materials community for which nonlinear and nonequilibrium approaches will have decisive roles and where productive teamwork among elements of modeling, simulations, synthesis, characterization and applications could be anticipated--particularly multiscale and nonequilibrium phenomena, and complex matter in and between fields of soft, hard and biomimetic materials. Principal topics were: (i) Complex organic and inorganic electronic materials, including hard, soft and biomimetic materials, self-assembly processes and photophysics; (ii) Microstructure and evolution in multiscale and hierarchical materials, including dynamic fracture and friction, dislocation and large-scale deformation, metastability, and inhomogeneity; and (iii) Equilibrium and nonequilibrium phases and phase transformations, emphasizing competing interactions, frustration, landscapes, glassy and stochastic dynamics, and energy focusing.

  8. MATERIAL TRACKING USING LANMAS

    SciTech Connect

    Armstrong, F.

    2010-06-07

    LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

  9. Canadian Materials 1972.

    ERIC Educational Resources Information Center

    Wintrob, Ralph, Ed.

    A variety of media is encompassed in this annotated awareness list of Canadian produced or Canadian oriented materials. Its purpose is to include all materials published or reprinted in 1972 which are suitable for use in school resource centers from kindergarten to twelfth grade. Main entries are arranged alphabetically by title with some subject…

  10. Packaging Your Training Materials

    ERIC Educational Resources Information Center

    Espeland, Pamela

    1977-01-01

    The types of packaging and packaging materials to use for training materials should be determined during the planning of the training programs, according to the packaging market. Five steps to follow in shopping for packaging are presented, along with a list of packaging manufacturers. (MF)

  11. Airframe materials for HSR

    NASA Technical Reports Server (NTRS)

    Bales, Thomas T.

    1992-01-01

    Vugraphs are presented to show the use of refractory materials for the skin of the High speed Civil Transport (HSCT). Examples are given of skin temperature ranges, failure mode weight distribution, tensile properties as a function of temperature, and components to be constructed from composite materials. The responsibilities of various aircraft companies for specific aircraft components are defined.

  12. NBS: Materials measurements

    NASA Technical Reports Server (NTRS)

    Manning, J. R.

    1981-01-01

    Measurement of materials properties and thermophysical properties is described. The topics discussed are: surface tensions and their variations with temperature and impurities; convection during unidirectional solidification: measurement of high temperature thermophysical properties of tungsten liquid and solid; thermodynamic properties of refractory materials at high temperatures; and experimental and theoretical studies in wetting and multilayer adsorption.

  13. Marine Education Materials System.

    ERIC Educational Resources Information Center

    Gammisch, Sue; Gray, Kevin

    1980-01-01

    Described is a marine education materials clearinghouse, the Marine Education Materials System (MEMS). MEMS classifies marine education documents and reproduces them on microfiche for distribution. There are 25 distribution centers, each of which has a collection of documents and provides assistance on a request basis to teachers. (Author/DS)

  14. Sex Education Materials.

    ERIC Educational Resources Information Center

    Singer-Magdoff, Laura

    1969-01-01

    After briefly discussing the philosophy of sex education and appraising generally the nature of the instructional methods and materials currently in use in the schools, the author provides brief but incisive reviews of a number of films, filmstrips, and other instructional materials dealing with sex. The reviews are continued in the succeeding…

  15. Nanocrystalline heterojunction materials

    SciTech Connect

    Elder, Scott H.; Su, Yali; Gao, Yufei; Heald, Steve M.

    2003-07-15

    Mesoporous nanocrystalline titanium dioxide heterojunction materials are disclosed. In one disclosed embodiment, materials comprising a core of titanium dioxide and a shell of a molybdenum oxide exhibit a decrease in their photoadsorption energy as the size of the titanium dioxide core decreases.

  16. Nanocrystalline Heterojunction Materials

    SciTech Connect

    Elder, Scott H.; Su, Yali; Gao, Yufei; Heald, Steve M.

    2004-02-03

    Mesoporous nanocrystalline titanium dioxide heterojunction materials and methods of making the same are disclosed. In one disclosed embodiment, materials comprising a core of titanium dioxide and a shell of a molybdenum oxide exhibit a decrease in their photoadsorption energy as the size of the titanium dioxide core decreases.

  17. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Loewy, R. G.; Wiberley, S. E.

    1985-01-01

    Various topics relating to composite structural materials for use in aircraft structures are discussed. The mechanical properties of high performance carbon fibers, carbon fiber-epoxy interface bonds, composite fractures, residual stress in high modulus and high strength carbon fibers, fatigue in composite materials, and the mechanical properties of polymeric matrix composite laminates are among the topics discussed.

  18. Environmental materials and interfaces

    SciTech Connect

    Not Available

    1991-11-01

    A workshop that explored materials and interfaces research needs relevant to national environmental concerns was conducted at Pacific Northwest Laboratory. The purposes of the workshop were to refine the scientific research directions being planned for the Materials and Interface Program in the Molecular Science Research Center (MSRC) and further define the research and user equipment to the included as part of the proposed Environmental and Molecular Science Laboratory (EMSL). Three plenary information sessions served to outline the background, objectives, and status of the MSRC and EMSL initiatives; selected specific areas with environmentally related materials; and the status of capabilities and facilities planned for the EMSL. Attention was directed to four areas where materials and interface science can have a significant impact on prevention and remediation of environmental problems: in situ detection and characterization of hazardous wastes (sensors), minimization of hazardous waste (separation membranes, ion exchange materials, catalysts), waste containment (encapsulation and barrier materials), and fundamental understanding of contaminant transport mechanisms. During all other sessions, the participants were divided into three working groups for detailed discussion and the preparation of a written report. The working groups focused on the areas of interface structure and chemistry, materials and interface stability, and materials synthesis. These recommendations and suggestions for needed research will be useful for other researchers in proposing projects and for suggesting collaborative work with MSRC researchers. 1 fig.

  19. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Wiberley, S. E.

    1978-01-01

    The purpose of the RPI composites program is to develop advanced technology in the areas of physical properties, structural concepts and analysis, manufacturing, reliability and life prediction. Concommitant goals are to educate engineers to design and use composite materials as normal or conventional materials. A multifaceted program was instituted to achieve these objectives.

  20. Materials inventory management manual

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This NASA Materials Inventory Management Manual (NHB 4100.1) is issued pursuant to Section 203(c)(1) of the National Aeronautics and Space Act of 1958 (42 USC 2473). It sets forth policy, performance standards, and procedures governing the acquisition, management and use of materials. This Manual is effective upon receipt.

  1. Materials Science and Engineering

    SciTech Connect

    Lesuer, D.R.

    1993-03-01

    Five papers are included: processing/characterization of laminated metal composites, casting process modeling, characterizing the failure of composite materials, fiber-optic Raman spectroscopy for cure monitoring of advanced polymer composites, and modeling superplastic materials. The papers are processed separately for the data base.

  2. Gravitation in Material Media

    ERIC Educational Resources Information Center

    Ridgely, Charles T.

    2011-01-01

    When two gravitating bodies reside in a material medium, Newton's law of universal gravitation must be modified to account for the presence of the medium. A modified expression of Newton's law is known in the literature, but lacks a clear connection with existing gravitational theory. Newton's law in the presence of a homogeneous material medium…

  3. Detecting Illicit Nuclear Materials

    SciTech Connect

    Kouzes, Richard T.

    2005-09-01

    The threat that weapons of mass destruction might enter the United States has led to a number of efforts for the detection and interdiction of nuclear, radiological, chemical, and biological weapons at our borders. There have been multiple deployments of instrumentation to detect radiation signatures to interdict radiological material, including weapons and weapons material worldwide.

  4. Thermal Protection Materials

    NASA Technical Reports Server (NTRS)

    Johnson, Sylvia M.

    2011-01-01

    Thermal protection materials and systems (TPS) are required to protect a vehicle returning from space or entering an atmosphere. The selection of the material depends on the heat flux, heat load, pressure, and shear and other mechanical loads imposed on the material, which are in turn determined by the vehicle configuration and size, location on the vehicle, speed, a trajectory, and the atmosphere. In all cases the goal is to use a material that is both reliable and efficient for the application. Reliable materials are well understood and have sufficient test data under the appropriate conditions to provide confidence in their performance. Efficiency relates to the behavior of a material under the specific conditions that it encounters TPS that performs very well at high heat fluxes may not be efficient at lower heat fluxes. Mass of the TPS is a critical element of efficiency. This talk will review the major classes of TPS, reusable or insulating materials and ablators. Ultra high temperature ceramics for sharp leading edges will also be reviewed. The talk will focus on the properties and behavior of these materials.

  5. Impacted material placement plans

    SciTech Connect

    Hickey, M.J.

    1997-01-29

    Impacted material placement plans (IMPP) are documents identifying the essential elements in placing remediation wastes into disposal facilities. Remediation wastes or impacted material(s) are those components used in the construction of the disposal facility exclusive of the liners and caps. The components might include soils, concrete, rubble, debris, and other regulatory approved materials. The IMPP provides the details necessary for interested parties to understand the management and construction practices at the disposal facility. The IMPP should identify the regulatory requirements from applicable DOE Orders, the ROD(s) (where a part of a CERCLA remedy), closure plans, or any other relevant agreements or regulations. Also, how the impacted material will be tracked should be described. Finally, detailed descriptions of what will be placed and how it will be placed should be included. The placement of impacted material into approved on-site disposal facilities (OSDF) is an integral part of gaining regulatory approval. To obtain this approval, a detailed plan (Impacted Material Placement Plan [IMPP]) was developed for the Fernald OSDF. The IMPP provides detailed information for the DOE, site generators, the stakeholders, regulatory community, and the construction subcontractor placing various types of impacted material within the disposal facility.

  6. 76 FR 35918 - Nixon Presidential Historical Materials; Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials; Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of Opening of Additional Materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  7. 77 FR 58179 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration ACTION: Notice of opening of additional materials SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  8. 75 FR 68384 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-05

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of Opening of Additional Materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  9. 77 FR 31400 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of Opening of Additional Materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  10. 76 FR 62856 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of Nixon Presidential Historical Materials by the Richard Nixon...

  11. 75 FR 30863 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  12. 76 FR 27092 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  13. Fingerprinting of Materials

    NASA Technical Reports Server (NTRS)

    Workman, Gary L

    1992-01-01

    Recent issues emerging in our fiscal and ecological environments have promulgated that federal agencies shall promote activities which respond to the improvement of both. In response to these developments, the National Aeronautics and Space Administration (NASA) has undertaken an innovative approach to improve the control of materials used in all NASA manufacturing activities. In concert with this goal, NASA is requiring that its contractors and their sub-contractors perform a more intensive consolidation of technologies that can provide an accounting of materials, which includes in-coming materials, materials in process, end-products and waste materials. The purpose of this handbook is to provide guidelines to NASA and its contractor personnel for the planning and implementation of chemical fingerprinting programs and to illustrate the chemical and statistical fundamentals needed for successful use of chemical fingerprinting.

  14. Materials Integrating Photochemical Upconversion.

    PubMed

    McCusker, Catherine E; Castellano, Felix N

    2016-04-01

    This review features recent experimental work focused on the preparation and characterization of materials that integrate photochemical upconversion derived from sensitized triplet-triplet annihilation, resulting in the conversion of low energy photons to higher energy light, thereby enabling numerous wavelength-shifting applications. Recent topical developments in upconversion include encapsulating or rigidifying fluid solutions to give them mechanical strength, adapting inert host materials to enable upconversion, and using photoactive materials that incorporate the sensitizer and/or the acceptor. The driving force behind translating photochemical upconversion from solution into hard and soft materials is the incorporation of upconversion into devices and other applications. At present, some of the most promising applications of upconversion materials include imaging and fluorescence microscopy, photoelectrochemical devices, water disinfection, and solar cell enhancement.

  15. Architected Cellular Materials

    NASA Astrophysics Data System (ADS)

    Schaedler, Tobias A.; Carter, William B.

    2016-07-01

    Additive manufacturing enables fabrication of materials with intricate cellular architecture, whereby progress in 3D printing techniques is increasing the possible configurations of voids and solids ad infinitum. Examples are microlattices with graded porosity and truss structures optimized for specific loading conditions. The cellular architecture determines the mechanical properties and density of these materials and can influence a wide range of other properties, e.g., acoustic, thermal, and biological properties. By combining optimized cellular architectures with high-performance metals and ceramics, several lightweight materials that exhibit strength and stiffness previously unachievable at low densities were recently demonstrated. This review introduces the field of architected materials; summarizes the most common fabrication methods, with an emphasis on additive manufacturing; and discusses recent progress in the development of architected materials. The review also discusses important applications, including lightweight structures, energy absorption, metamaterials, thermal management, and bioscaffolds.

  16. Extraterrestrial materials processing

    NASA Technical Reports Server (NTRS)

    Steurer, W. H.

    1982-01-01

    The first year results of a multi-year study of processing extraterrestrial materials for use in space are summarized. Theoretically, there are potential major advantages to be derived from the use of such materials for future space endeavors. The types of known or postulated starting raw materials are described including silicate-rich mixed oxides on the Moon, some asteroids and Mars; free metals in some asteroids and in small quantities in the lunar soil; and probably volatiles like water and CO2 on Mars and some asteroids. Candidate processes for space materials are likely to be significantly different from their terrestrial counterparts largely because of: absence of atmosphere; lack of of readily available working fluids; low- or micro-gravity; no carbon-based fuels; readily available solar energy; and severe constraints on manned intervention. The extraction of metals and oxygen from lunar material by magma electrolysis or by vapor/ion phase separation appears practical.

  17. Materials Integrating Photochemical Upconversion.

    PubMed

    McCusker, Catherine E; Castellano, Felix N

    2016-04-01

    This review features recent experimental work focused on the preparation and characterization of materials that integrate photochemical upconversion derived from sensitized triplet-triplet annihilation, resulting in the conversion of low energy photons to higher energy light, thereby enabling numerous wavelength-shifting applications. Recent topical developments in upconversion include encapsulating or rigidifying fluid solutions to give them mechanical strength, adapting inert host materials to enable upconversion, and using photoactive materials that incorporate the sensitizer and/or the acceptor. The driving force behind translating photochemical upconversion from solution into hard and soft materials is the incorporation of upconversion into devices and other applications. At present, some of the most promising applications of upconversion materials include imaging and fluorescence microscopy, photoelectrochemical devices, water disinfection, and solar cell enhancement. PMID:27573144

  18. Materials of Gasification

    SciTech Connect

    2005-09-15

    The objective of this project was to accumulate and establish a database of construction materials, coatings, refractory liners, and transitional materials that are appropriate for the hardware and scale-up facilities for atmospheric biomass and coal gasification processes. Cost, fabricability, survivability, contamination, modes of corrosion, failure modes, operational temperatures, strength, and compatibility are all areas of materials science for which relevant data would be appropriate. The goal will be an established expertise of materials for the fossil energy area within WRI. This would be an effort to narrow down the overwhelming array of materials information sources to the relevant set which provides current and accurate data for materials selection for fossil fuels processing plant. A significant amount of reference material on materials has been located, examined and compiled. The report that describes these resources is well under way. The reference material is in many forms including texts, periodicals, websites, software and expert systems. The most important part of the labor is to refine the vast array of available resources to information appropriate in content, size and reliability for the tasks conducted by WRI and its clients within the energy field. A significant has been made to collate and capture the best and most up to date references. The resources of the University of Wyoming have been used extensively as a local and assessable location of information. As such, the distribution of materials within the UW library has been added as a portion of the growing document. Literature from recent journals has been combed for all pertinent references to high temperature energy based applications. Several software packages have been examined for relevance and usefulness towards applications in coal gasification and coal fired plant. Collation of the many located resources has been ongoing. Some web-based resources have been examined.

  19. Materials Research Capabilities

    NASA Technical Reports Server (NTRS)

    Stofan, Andrew J.

    1986-01-01

    Lewis Research Center, in partnership with U.S. industry and academia, has long been a major force in developing advanced aerospace propulsion and power systems. One key aspect that made many of these systems possible has been the availability of high-performance, reliable, and long-life materials. To assure a continuing flow of new materials and processing concepts, basic understanding to guide such innovation, and technological support for development of major NASA systems, Lewis has supported a strong in-house materials research activity. Our researchers have discovered new alloys, polymers, metallic composites, ceramics, coatings, processing techniques, etc., which are now also in use by U.S. industry. This brochure highlights selected past accomplishments of our materials research and technology staff. It also provides many examples of the facilities available with which we can conduct materials research. The nation is now beginning to consider integrating technology for high-performance supersonic/hypersonic aircraft, nuclear space power systems, a space station, and new research areas such as materials processing in space. As we proceed, I am confident that our materials research staff will continue to provide important contributions which will help our nation maintain a strong technology position in these areas of growing world competition. Lewis Research Center, in partnership with U.S. industry and academia, has long been a major force in developing advanced aerospace propulsion and power systems. One key aspect that made many of these systems possible has been the availability of high-performance, reliable, and long-life materials. To assure a continuing flow of new materials and processing concepts, basic understanding to guide such innovation, and technological support for development of major NASA systems, Lewis has supported a strong in-house materials research activity. Our researchers have discovered new alloys, polymers, metallic composites

  20. Electronic and optical properties of tungsten oxide related materials and first-principles theory of electrochromism

    NASA Astrophysics Data System (ADS)

    Xue, Yu

    coloration mechanism of WO3 upon charge insertion. The calculated dielectric functions, reflectance, transmission and absorption coefficient agree very well with experiments. Our results explain the systematic change in color of Na3WO3 from blue to golden-yellow with increasing sodium concentration x. We find that proper accounts for the free-carriers contribution to the optical response are critical for a quantitative understanding of the coloration mechanism in this system. Besides WO3, we have studied another "smart material", VO2. The results are reported in chapter 6. The most interesting property of VO2 is its metal-insulator transition (MIT) at T c=340 K. The crystal structure changes from a high-temperature rutile phase to a low-temperature monoclinic phase at Tc. The MIT in VO2 has led to many practical applications such as thermocoatings, optical switching devices etc. However, it has long been a controversial issue regarding the mechanism behind the MIT. It is still not clear whether the insulating behavior is driven by the electron correlation or structural distortions. In this work, we perform first-principles electronic structure calculation using both LDA and LDAU method. It is found that the correlation effect is very important to explain the insulating phase of VO2. However, correlation effects alone cannot help open a band gap for the insulating phase of VO2. Structural distortion also plays an important role. It seems that it is the subtle interplay between the electron-electron correlation and electron-lattice interaction that ultimately drives the development of an insulating gap.

  1. Cathode material for electrochemical cells

    SciTech Connect

    Ryan, D.M.

    1993-08-24

    A primary cell is described having an anode material, an electrolyte material and a cathode material, wherein said cathode material, in the predischarge condition thereof, is K[sub 3]V[sub 5]O[sub 14].

  2. Materials at LANL

    SciTech Connect

    Taylor, Antoinette J

    2010-01-01

    Exploring the physics, chemistry, and metallurgy of materials has been a primary focus of Los Alamos National Laboratory since its inception. In the early 1940s, very little was known or understood about plutonium, uranium, or their alloys. In addition, several new ionic, polymeric, and energetic materials with unique properties were needed in the development of nuclear weapons. As the Laboratory has evolved, and as missions in threat reduction, defense, energy, and meeting other emerging national challenges have been added, the role of materials science has expanded with the need for continued improvement in our understanding of the structure and properties of materials and in our ability to synthesize and process materials with unique characteristics. Materials science and engineering continues to be central to this Laboratory's success, and the materials capability truly spans the entire laboratory - touching upon numerous divisions and directorates and estimated to include >1/3 of the lab's technical staff. In 2006, Los Alamos and LANS LLC began to redefine our future, building upon the laboratory's established strengths and promoted by strongly interdependent science, technology and engineering capabilities. Eight Grand Challenges for Science were set forth as a technical framework for bridging across capabilities. Two of these grand challenges, Fundamental Understanding of Materials and Superconductivity and Actinide Science. were clearly materials-centric and were led out of our organizations. The complexity of these scientific thrusts was fleshed out through workshops involving cross-disciplinary teams. These teams refined the grand challenge concepts into actionable descriptions to be used as guidance for decisions like our LDRD strategic investment strategies and as the organizing basis for our external review process. In 2008, the Laboratory published 'Building the Future of Los Alamos. The Premier National Security Science Laboratory,' LA-UR-08

  3. NSUF Irradiated Materials Library

    SciTech Connect

    Cole, James Irvin

    2015-09-01

    The Nuclear Science User Facilities has been in the process of establishing an innovative Irradiated Materials Library concept for maximizing the value of previous and on-going materials and nuclear fuels irradiation test campaigns, including utilization of real-world components retrieved from current and decommissioned reactors. When the ATR national scientific user facility was established in 2007 one of the goals of the program was to establish a library of irradiated samples for users to access and conduct research through competitively reviewed proposal process. As part of the initial effort, staff at the user facility identified legacy materials from previous programs that are still being stored in laboratories and hot-cell facilities at the INL. In addition other materials of interest were identified that are being stored outside the INL that the current owners have volunteered to enter into the library. Finally, over the course of the last several years, the ATR NSUF has irradiated more than 3500 specimens as part of NSUF competitively awarded research projects. The Logistics of managing this large inventory of highly radioactive poses unique challenges. This document will describe materials in the library, outline the policy for accessing these materials and put forth a strategy for making new additions to the library as well as establishing guidelines for minimum pedigree needed to be included in the library to limit the amount of material stored indefinitely without identified value.

  4. Millimeter-Wave Thermal Analysis Development and Application to GEN IV Reactor Materials

    SciTech Connect

    Wosko, Paul; Sundram, S. K.

    2012-10-16

    New millimeter-wave thermal analysis instrumentation has been developed and studied for characterization of materials required for diverse fuel and structural needs in high temperature reactor environments such as the Next Generation Nuclear Plant (NGNP). A two-receiver 137 GHz system with orthogonal polarizations for anisotropic resolution of material properties has been implemented at MIT. The system was tested with graphite and silicon carbide specimens at temperatures up to 1300 ºC inside an electric furnace. The analytic and hardware basis for active millimeter-wave radiometry of reactor materials at high temperature has been established. Real-time, non contact measurement sensitivity to anisotropic surface emissivity and submillimeter surface displacement was demonstrated. The 137 GHz emissivity of reactor grade graphite (NBG17) from SGL Group was found to be low, ~ 5 %, in the 500 – 1200 °C range and increases by a factor of 2 to 4 with small linear grooves simulating fracturing. The low graphite emissivity would make millimeter-wave active radiometry a sensitive diagnostic of graphite changes due to environmentally induced stress fracturing, swelling, or corrosion. The silicon carbide tested from Ortek, Inc. was found to have a much higher emissivity at 137 GHz of ~90% Thin coatings of silicon carbide on reactor grade graphite supplied by SGL Group were found to be mostly transparent to millimeter-waves, increasing the 137 GHz emissivity of the coated reactor grade graphite to about ~14% at 1250 ºC.

  5. Investigation of real materials with strong electronic correlations by the LDA+DMFT method.

    PubMed

    Anisimov, V I; Lukoyanov, A V

    2014-02-01

    Materials with strong electronic correlations are at the cutting edge of experimental and theoretical studies, capturing the attention of researchers for a great variety of interesting phenomena: metal-insulator, phase and magnetic spin transitions, `heavy fermion' systems, interplay between magnetic order and superconductivity, appearance and disappearance of local magnetic moments, and transport property anomalies. It is clear that the richness of physical phenomena for these compounds is a result of partially filled 3d, 4f or 5f electron shells with local magnetic moments preserved in the solid state. Strong interactions of d and f electrons with each other and with itinerant electronic states of the material are responsible for its anomalous properties. Electronic structure calculations for strongly correlated materials should explicitly take into account Coulombic interactions between d or f electrons. Recent advances in this field are related to the development of the LDA+DMFT method, which combines local density approximation (LDA) with dynamical mean-field theory (DMFT) to account for electronic correlation effects. In recent years, LDA+DMFT has allowed the successful treatment not only of simple systems but also of complicated real compounds. Nowadays, the LDA+DMFT method is the state-of-the-art tool for investigating correlated metals and insulators, spin and metal-insulator transitions (MIT) in transition-metal compounds in paramagnetic and magnetically ordered phases.

  6. Materials science and engineering

    SciTech Connect

    Holden, T.M.

    1995-10-01

    The science-based stockpile stewardship program emphasizes a better understanding of how complex components function through advanced computer calculations. Many of the problem areas are in the behavior of materials making up the equipment. The Los Alamos Neutron Science Center (LANSCE) can contribute to solving these problems by providing diagnostic tools to examine parts noninvasively and by providing the experimental tools to understand material behavior in terms of both the atomic structure and the microstructure. Advanced computer codes need experimental information on material behavior in response to stress, temperature, and pressure as input, and they need benchmarking experiments to test the model predictions for the finished part.

  7. Materials for syngas coolers

    NASA Astrophysics Data System (ADS)

    Perkins, R. A.; Morse, G.; Coons, W. C.

    1982-08-01

    A technical basis for materials selection and laboratory testing of practical boiler tube materials which will provide reliable long term service in syngas coolers for coal gasification combined cycle power plants is outlined. The resistance of low alloy steel, stainless steels, and aluminum rich coatings to attach by a high sulfur, medium Btu coal gasification atmosphere was evaluated at 300 to 500 deg C. The materials may have adequate resistance for long time service in radiant coolers operating up to 500 deg C on high sulfur medium Btu gas. Performance is analyzed for thermodynamic and kinetic properties and recommendations for long term tests and development of protective coatings are presented.

  8. Electrically conductive composite material

    DOEpatents

    Clough, R.L.; Sylwester, A.P.

    1988-06-20

    An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistent pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like. 2 figs.

  9. Material Challenges and Perspectives

    SciTech Connect

    Choi, Daiwon; Wang, Wei; Yang, Zhenguo

    2011-12-14

    General history and principals of Li-ion battery, characterization techniques and terminology of its operation will be discussed and explained. Current Li-ion battery applications and comparison to other energy storage and conversion systems will be outlined. Chemistry, material and design of currently commercialized Li-ion batteries will be discussed including various electrode materials for cathodes and anodes. The electrode material candidates and its physical and chemical properties including crystal structure, capacity, cycling stability, cost and safety. Also, current limitations of Li-ion batteries will be discussed.

  10. Electrically conductive composite material

    DOEpatents

    Clough, Roger L.; Sylwester, Alan P.

    1989-01-01

    An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistant pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like.

  11. ATS materials/manufacturing

    SciTech Connect

    Karnitz, M.A.; Wright, I.G.; Ferber, M.K.

    1997-11-01

    The Materials/Manufacturing Technology subelement is a part of the base technology portion of the Advanced Turbine Systems (ATS) Program. The work in this subelement is being performed predominantly by industry with assistance from national laboratories and universities. The projects in this subelement are aimed toward hastening the incorporation of new materials and components in gas turbines. Work is currently ongoing on thermal barrier coatings (TBCs), the scale-up of single crystal airfoil manufacturing technologies, materials characterization, and technology information exchange. This paper presents highlights of the activities during the past year. 12 refs., 24 figs., 4 tabs.

  12. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Loewy, R.; Wiberley, S. E.

    1986-01-01

    Overall emphasis is on basic long-term research in the following categories: constituent materials, composite materials, generic structural elements, processing science technology; and maintaining long-term structural integrity. Research in basic composition, characteristics, and processing science of composite materials and their constituents is balanced against the mechanics, conceptual design, fabrication, and testing of generic structural elements typical of aerospace vehicles so as to encourage the discovery of unusual solutions to present and future problems. Detailed descriptions of the progress achieved in the various component parts of this comprehensive program are presented.

  13. Biomedical materials and devices

    SciTech Connect

    Hanker, J. S. ); Giammara, B. L. )

    1989-01-01

    This conference reports on how biomedical materials and devices are undergoing important changes that require interdisciplinary approaches, innovation expertise, and access to sophisticated preparative and analytical equipment and methodologies. The interaction of materials scientists with biomedical, biotechnological, bioengineering and clinical scientists in the last decade has resulted in major advances in therapy. New therapeutic modalities and bioengineering methods and devices for the continuous removal of toxins or pathologic products present in arthritis, atherosclerosis and malignancy are presented. Novel monitoring and controlled drug delivery systems and discussions of materials such as blood or plasma substitutes, artificial organs, and bone graft substitutes are discussed.

  14. Investigating Encrypted Material

    NASA Astrophysics Data System (ADS)

    McGrath, Niall; Gladyshev, Pavel; Kechadi, Tahar; Carthy, Joe

    When encrypted material is discovered during a digital investigation and the investigator cannot decrypt the material then s/he is faced with the problem of how to determine the evidential value of the material. This research is proposing a methodology of extracting probative value from the encrypted file of a hybrid cryptosystem. The methodology also incorporates a technique for locating the original plaintext file. Since child pornography (KP) images and terrorist related information (TI) are transmitted in encrypted format the digital investigator must ask the question Cui Bono? - who benefits or who is the recipient? By doing this the scope of the digital investigation can be extended to reveal the intended recipient.

  15. Fissile material detector

    DOEpatents

    Ivanov, Alexander I.; Lushchikov, Vladislav I.; Shabalin, Eugeny P.; Maznyy, Nikita G.; Khvastunov, Michael M.; Rowland, Mark

    2002-01-01

    A detector for fissile materials which provides for integrity monitoring of fissile materials and can be used for nondestructive assay to confirm the presence of a stable content of fissile material in items. The detector has a sample cavity large enough to enable assay of large items of arbitrary configuration, utilizes neutron sources fabricated in spatially extended shapes mounted on the endcaps of the sample cavity, incorporates a thermal neutron filter insert with reflector properties, and the electronics module includes a neutron multiplicity coincidence counter.

  16. Gravity and Granular Materials

    NASA Technical Reports Server (NTRS)

    Behringer, R. P.; Hovell, Daniel; Kondic, Lou; Tennakoon, Sarath; Veje, Christian

    1999-01-01

    We describe experiments that probe a number of different types of granular flow where either gravity is effectively eliminated or it is modulated in time. These experiments include the shaking of granular materials both vertically and horizontally, and the shearing of a 2D granular material. For the shaken system, we identify interesting dynamical phenomena and relate them to standard simple friction models. An interesting application of this set of experiments is to the mixing of dissimilar materials. For the sheared system we identify a new kind of dynamical phase transition.

  17. Encapsulation materials research

    NASA Technical Reports Server (NTRS)

    Willis, P. B.

    1984-01-01

    Encapsulation materials for solar cells were investigated. The different phases consisted of: (1) identification and development of low cost module encapsulation materials; (2) materials reliability examination; and (3) process sensitivity and process development. It is found that outdoor photothermal aging devices (OPT) are the best accelerated aging methods, simulate worst case field conditions, evaluate formulation and module performance and have a possibility for life assessment. Outdoor metallic copper exposure should be avoided, self priming formulations have good storage stability, stabilizers enhance performance, and soil resistance treatment is still effective.

  18. Piezoelectric composite materials

    NASA Technical Reports Server (NTRS)

    Kiraly, L. J. (Inventor)

    1983-01-01

    A laminated structural devices has the ability to change shape, position and resonant frequency without using discrete motive components. The laminate may be a combination of layers of a piezoelectrically active, nonconductive matrix material. A power source selectively places various levels of charge in electrically conductive filaments imbedded in the respective layers to produce various configurations in a predetermined manner. The layers may be electrically conductive having imbedded piezoelectrically active filaments. A combination of layers of electrically conductive material may be laminated to layers of piezoelectrically active material.

  19. Composite Structural Materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberly, S. E.

    1984-01-01

    The development and application of filamentary composite materials, is considered. Such interest is based on the possibility of using relatively brittle materials with high modulus, high strength, but low density in composites with good durability and high tolerance to damage. Fiber reinforced composite materials of this kind offer substantially improved performance and potentially lower costs for aerospace hardware. Much progress has been made since the initial developments in the mid 1960's. There were only limited applied to the primary structure of operational vehicles, mainly as aircrafts.

  20. Cookoff of energetic materials

    SciTech Connect

    Baer, M.R.; Hobbs, M.L.; Gross, R.J.; Schmitt, R.G.

    1998-09-01

    An overview of cookoff modeling at Sandia National Laboratories is presented aimed at assessing the violence of reaction following cookoff of confined energetic materials. During cookoff, the response of energetic materials is known to involve coupled thermal/chemical/mechanical processes which induce thermal damage to the energetic material prior to the onset of ignition. These damaged states enhance shock sensitivity and lead to conditions favoring self-supported accelerated combustion. Thus, the level of violence depends on the competition between pressure buildup and stress release due to the loss of confinement. To model these complex processes, finite element-based analysis capabilities are being developed which can resolve coupled heat transfer with chemistry, quasi-static structural mechanics and dynamic response. Numerical simulations that assess the level of violence demonstrate the importance of determining material damage in pre- and post-ignition cookoff events.

  1. Materials research at CMAM

    SciTech Connect

    Zucchiatti, Alessandro

    2013-07-18

    The Centro de Micro Analisis de Materiales (CMAM) is a research centre of the Universidad Autonoma de Madrid dedicated to the modification and analysis of materials using ion beam techniques. The infrastructure, based on a HVEE 5MV tandem accelerator, provided with a coaxial Cockcroft Walton charging system, is fully open to research groups of the UAM, to other public research institutions and to private enterprises. The CMAM research covers a few important lines such as advanced materials, surface science, biomedical materials, cultural heritage, materials for energy production. The Centre gives as well support to university teaching and technical training. A detail description of the research infrastructures and their use statistics will be given. Some of the main research results will be presented to show the progress of research in the Centre in the past few years and to motivate the strategic plans for the forthcoming.

  2. Heavy Vehicle Propulsion Materials

    SciTech Connect

    Ray Johnson

    2000-01-31

    The objectives are to Provide Key Enabling Materials Technologies to Increase Energy Efficiency and Reduce Exhaust Emissions. The following goals are listed: Goal 1: By 3rd quarter 2002, complete development of materials enabling the maintenance or improvement of fuel efficiency {ge} 45% of class 7-8 truck engines while meeting the EPA/Justice Department ''Consent Decree'' for emissions reduction. Goal 2: By 4th quarter 2004, complete development of enabling materials for light-duty (class 1-2) diesel truck engines with efficiency over 40%, over a wide range of loads and speeds, while meeting EPA Tier 2 emission regulations. Goal 3: By 4th quarter 2006, complete development of materials solutions to enable heavy-duty diesel engine efficiency of 50% while meeting the emission reduction goals identified in the EPA proposed rule for heavy-duty highway engines.''

  3. Materials engineering data base

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The various types of materials related data that exist at the NASA Marshall Space Flight Center and compiled into databases which could be accessed by all the NASA centers and by other contractors, are presented.

  4. Degradation of Spacecraft Materials

    NASA Technical Reports Server (NTRS)

    Dever, Joyce; Banks, Bruce; deGroh, Kim; Miller, Sharon

    2004-01-01

    This chapter includes descriptions of specific space environmental threats to exterior spacecraft materials. The scope will be confined to effects on exterior spacecraft surfaces, and will not, therefore, address environmental effects on interior spacecraft systems, such as electronics. Space exposure studies and laboratory simulations of individual and combined space environemntal threats will be summarized. A significant emphasis is placed on effects of Earth orbit environments, because the majority of space missions have been flown in Earth orbits which have provided a significant amount of data on materials effects. Issues associated with interpreting materials degradation results will be discussed, and deficiencies of ground testing will be identified. Recommendations are provided on reducing or preventing space environmental degradation through appropriate materials selection.

  5. Holographic Recording Materials Development

    NASA Technical Reports Server (NTRS)

    Verber, C. M.; Schwerzel, R. E.; Perry, P. J.; Craig, R. A.

    1976-01-01

    Organic photorefractive materials were evaluated for application in a reversible holographic memory system. Representative indigo and thioindigo derivatives and several stilbene derivatives were studied as well as 15, 16-dialkyldihydropyrene derivatives the following goals were achieved: (1) the successful writing of phase holograms in a thioindigo/polymer gel system, (2) the successful writing and erasing of phase holograms in a variety of indigo/polymer gel and indigo/solid polymer systems, and (3) the identification of indigoid dyes and 15, 16-dialkyldihydropyrene derivatives as materials potentially suitable for utilization in an operational system. Photochemical studies of the stilbene, indigo, thioindigo, and dialkyldihydropyrene derivatives in solution and in a variety of polymer matrix materials were conducted with the goal of optimizing the photorefractive behavior of the chemical system as a whole. The spectroscopic properties required of optimal photorefractive materials were identified, and it was shown that both the indigoid dyes and the dialkyldihydropyrenes closely match the required properties.

  6. Dental obturation materials

    NASA Astrophysics Data System (ADS)

    Stockton, Elizabeth; Chudej, Lauren; Bilyeu, Brian; Brostow, Witold

    2006-10-01

    During the last decades, people have tried to develop a better material for use in dental obturation materials. This new material should meet the following requirements: durability, wear resistance, biocompatibility and chemical adhesion to dentin enamel. Wear resistance is very important and it is related with the service life of dental replacements. We have obtained aesthetically promising novel nano composites that can be used as dental replacements. The main objective of this work is to study the scratch and wear resistance of these nano composites. To meet this goal, scratch tests are performed using a micro scratch tester machine (CSEM), where a diamond indenter is used to make the scratch and the penetration of this indenter is measured with high resolution (7nm). We will be looking at the penetration depth (Rp) and the residual (or healing) depth (Rh) to calculate the percent recovery. These measurements represent the scratch resistance of the material.

  7. Building Materials Property Table

    SciTech Connect

    2010-04-16

    This information sheet describes a table of some of the key technical properties of many of the most common building materials taken from ASHRAE Fundamentals - 2001, Moisture Control in Buildings, CMHC, NRC/IRC, IEA Annex 24, and manufacturer data.

  8. Lunar material transport vehicle

    NASA Technical Reports Server (NTRS)

    Fisher, Charles D.; Lyons, Douglas; Wilkins, W. Allen, Jr.; Whitehead, Harry C., Jr.

    1988-01-01

    The proposed vehicle, the Lunar Material Transport Vehicle (LMTV), has a mission objective of efficient lunar soil material transport. The LMTV was designed to meet a required set of performance specifications while operating under a given set of constraints. The LMTV is essentially an articulated steering, double-ended dump truck. The vehicle moves on four wheels and has two identical chassis halves. Each half consists of a chassis frame, a material bucket, two wheels with integral curvilinear synchronous motors, a fuel cell and battery arrangement, an electromechanically actuated dumping mechanism, and a powerful microprocessor. The vehicle, as designed, is capable of transporting up to 200 cu ft of material over a one mile round trip per hour. The LMTV is capable of being operated from a variety of sources. The vehicle has been designed as simply as possible with attention also given to secondary usage of components.

  9. Electrically conductive material

    DOEpatents

    Singh, J.P.; Bosak, A.L.; McPheeters, C.C.; Dees, D.W.

    1993-09-07

    An electrically conductive material is described for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO[sub 2] as a matrix and 6-19 wt. % monoclinic ZrO[sub 2] formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO[sub 2] as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns. 8 figures.

  10. Electrically conductive material

    DOEpatents

    Singh, Jitendra P.; Bosak, Andrea L.; McPheeters, Charles C.; Dees, Dennis W.

    1993-01-01

    An electrically conductive material for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO.sub.2 as a matrix and 6-19 wt. % monoclinic ZrO.sub.2 formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO.sub.2 as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns.

  11. Dynamics of Granular Materials

    NASA Technical Reports Server (NTRS)

    Behringer, Robert P.

    1996-01-01

    Granular materials exhibit a rich variety of dynamical behavior, much of which is poorly understood. Fractal-like stress chains, convection, a variety of wave dynamics, including waves which resemble capillary waves, l/f noise, and fractional Brownian motion provide examples. Work beginning at Duke will focus on gravity driven convection, mixing and gravitational collapse. Although granular materials consist of collections of interacting particles, there are important differences between the dynamics of a collections of grains and the dynamics of a collections of molecules. In particular, the ergodic hypothesis is generally invalid for granular materials, so that ordinary statistical physics does not apply. In the absence of a steady energy input, granular materials undergo a rapid collapse which is strongly influenced by the presence of gravity. Fluctuations on laboratory scales in such quantities as the stress can be very large-as much as an order of magnitude greater than the mean.

  12. Instrumentation for Materials Research

    ERIC Educational Resources Information Center

    Claassen, Richard S.

    1976-01-01

    Discusses how sophisticated instrumentation techniques yield practical results in three typical materials problems: fracture analysis, joining, and compatibility. Describes techniques such as scanning and transmission electron microscopy, and Auger spectroscopy. (MLH)

  13. Mesoporous carbon materials

    SciTech Connect

    Dai, Sheng; Wang, Xiqing

    2012-02-14

    The invention is directed to a method for fabricating a mesoporous carbon material, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic compound or material, (iii) a crosslinkable aldehyde component, and (iv) at least 0.5 M concentration of a strong acid having a pKa of or less than -2, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a mesoporous carbon material. The invention is also directed to a mesoporous carbon material having an improved thermal stability, preferably produced according to the above method.

  14. Magnetocaloric materials: Strained relations

    NASA Astrophysics Data System (ADS)

    Nordblad, Per

    2013-01-01

    The magnetocaloric effect could form the basis for efficient refrigeration technologies. The finding that large and reversible magnetocaloric effects can be induced through a strain-mediated feedback mechanism may expand the range of available magnetocaloric materials.

  15. Ceramic breeder materials

    SciTech Connect

    Johnson, C.E.

    1990-01-01

    The breeding blanket is a key component of the fusion reactor because it directly involves tritium breeding and energy extraction, both of which are critical to development of fusion power. The lithium ceramics continue to show promise as candidate breeder materials. This promise was recognized by the International Thermonuclear Reactor (ITER) design team in its selection of ceramics as the first option for the ITER breeder material. Blanket design studies have indicated properties in the candidate materials data base that need further investigation. Current studies are focusing on tritium release behavior at high burnup, changes in thermophysical properties with burnup, compatibility between the ceramic breeder and beryllium multiplier, and phase changes with burnup. Laboratory and in-reactor tests, some as part of an international collaboration for development of ceramic breeder materials, are underway. 32 refs., 1 fig., 1 tab.

  16. Nuclear material operations manual

    SciTech Connect

    Tyler, R.P.

    1981-02-01

    This manual provides a concise and comprehensive documentation of the operating procedures currently practiced at Sandia National Laboratories with regard to the management, control, and accountability of nuclear materials. The manual is divided into chapters which are devoted to the separate functions performed in nuclear material operations-management, control, accountability, and safeguards, and the final two chapters comprise a document which is also issued separately to provide a summary of the information and operating procedures relevant to custodians and users of radioactive and nuclear materials. The manual also contains samples of the forms utilized in carrying out nuclear material activities. To enhance the clarity of presentation, operating procedures are presented in the form of playscripts in which the responsible organizations and necessary actions are clearly delineated in a chronological fashion from the initiation of a transaction to its completion.

  17. Unusual spacecraft materials

    NASA Technical Reports Server (NTRS)

    Post, Jonathan V.

    1990-01-01

    For particularly innovative space exploration missions, unusual requirements are levied on the structural components of the spacecraft. In many cases, the preferred solution is the utilization of unusual materials. This trend is forecast to continue. Several hypothetic examples are discussed.

  18. Reversible hydrogen storage materials

    DOEpatents

    Ritter, James A.; Wang, Tao; Ebner, Armin D.; Holland, Charles E.

    2012-04-10

    In accordance with the present disclosure, a process for synthesis of a complex hydride material for hydrogen storage is provided. The process includes mixing a borohydride with at least one additive agent and at least one catalyst and heating the mixture at a temperature of less than about 600.degree. C. and a pressure of H.sub.2 gas to form a complex hydride material. The complex hydride material comprises MAl.sub.xB.sub.yH.sub.z, wherein M is an alkali metal or group IIA metal, Al is the element aluminum, x is any number from 0 to 1, B is the element boron, y is a number from 0 to 13, and z is a number from 4 to 57 with the additive agent and catalyst still being present. The complex hydride material is capable of cyclic dehydrogenation and rehydrogenation and has a hydrogen capacity of at least about 4 weight percent.

  19. Tough Composite Materials

    NASA Technical Reports Server (NTRS)

    Vosteen, L. F. (Compiler); Johnson, N. J. (Compiler); Teichman, L. A. (Compiler)

    1984-01-01

    Papers and working group summaries are presented which address composite material behavior and performance improvement. Topic areas include composite fracture toughness and impact characterization, constituent properties and interrelationships, and matrix synthesis and characterization.

  20. Photoconductivity in Dirac materials

    SciTech Connect

    Shao, J. M.; Yang, G. W.

    2015-11-15

    Two-dimensional (2D) Dirac materials including graphene and the surface of a three-dimensional (3D) topological insulator, and 3D Dirac materials including 3D Dirac semimetal and Weyl semimetal have attracted great attention due to their linear Dirac nodes and exotic properties. Here, we use the Fermi’s golden rule and Boltzmann equation within the relaxation time approximation to study and compare the photoconductivity of Dirac materials under different far- or mid-infrared irradiation. Theoretical results show that the photoconductivity exhibits the anisotropic property under the polarized irradiation, but the anisotropic strength is different between 2D and 3D Dirac materials. The photoconductivity depends strongly on the relaxation time for different scattering mechanism, just like the dark conductivity.

  1. Materials research at CMAM

    NASA Astrophysics Data System (ADS)

    Zucchiatti, Alessandro

    2013-07-01

    The Centro de Micro Analisis de Materiales (CMAM) is a research centre of the Universidad Autónoma de Madrid dedicated to the modification and analysis of materials using ion beam techniques. The infrastructure, based on a HVEE 5MV tandem accelerator, provided with a coaxial Cockcroft Walton charging system, is fully open to research groups of the UAM, to other public research institutions and to private enterprises. The CMAM research covers a few important lines such as advanced materials, surface science, biomedical materials, cultural heritage, materials for energy production. The Centre gives as well support to university teaching and technical training. A detail description of the research infrastructures and their use statistics will be given. Some of the main research results will be presented to show the progress of research in the Centre in the past few years and to motivate the strategic plans for the forthcoming.

  2. Materials engineering for immunomodulation.

    PubMed

    Hubbell, Jeffrey A; Thomas, Susan N; Swartz, Melody A

    2009-11-26

    The engineering of materials that can modulate the immune system is an emerging field that is developing alongside immunology. For therapeutic ends such as vaccine development, materials are now being engineered to deliver antigens through specific intracellular pathways, allowing better control of the way in which antigens are presented to one of the key types of immune cell, T cells. Materials are also being designed as adjuvants, to mimic specific 'danger' signals in order to manipulate the resultant cytokine environment, which influences how antigens are interpreted by T cells. In addition to offering the potential for medical advances, immunomodulatory materials can form well-defined model systems, helping to provide new insight into basic immunobiology.

  3. CHARACTERIZATION OF DAMAGED MATERIALS

    SciTech Connect

    Hsu, P C; Dehaven, M; McClelland, M; Chidester, S; Maienschein, J L

    2006-06-23

    Thermal damage experiments were conducted on LX-04, LX-10, and LX-17 at high temperatures. Both pristine and damaged samples were characterized for their material properties. A pycnometer was used to determine sample true density and porosity. Gas permeability was measured in a newly procured system (diffusion permeameter). Burn rate was measured in the LLNL strand burner. Weight losses upon thermal exposure were insignificant. Damaged pressed parts expanded, resulting in a reduction of bulk density by up to 10%. Both gas permeabilities and burn rates of the damaged samples increased by several orders of magnitude due to higher porosity and lower density. Moduli of the damaged materials decreased significantly, an indication that the materials became weaker mechanically. Damaged materials were more sensitive to shock initiation at high temperatures. No significant sensitization was observed when the damaged samples were tested at room temperature.

  4. Computational Materials Research

    NASA Technical Reports Server (NTRS)

    Veazie, David R.

    1998-01-01

    High temperature thermoplastic polyimide polymers are incorporated in engineering structures in the form of matrix materials in advanced fiber composites and adhesives in bonded joints. Developing analytical tools to predict long term performance and screen for final materials selection for polymers is the impetus for intensive studies at NASA and major industry based airframe developers. These fiber-reinforced polymeric composites (FRPCs) combine high strength with lightweight. In addition, they offer corrosion and fatigue resistance, a reduction in parts count, and new possibilities for control through aeroelastic tailoring and "smart" structures containing fully-integrated sensors and actuators. However, large-scale acceptance and use of polymer composites has historically been extremely slow. Reasons for this include a lack of familiarity of designers with the materials; the need for new tooling and new inspection and repair infrastructures; and high raw materials and fabrication costs.

  5. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1979-01-01

    Technology utilization of fiber reinforced composite materials is discussed in the areas of physical properties, and life prediction. Programs related to the Composite Aircraft Program are described in detail.

  6. Moldable cork ablation material

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A successful thermal ablative material was manufactured. Moldable cork sheets were tested for density, tensile strength, tensile elongation, thermal conductivity, compression set, and specific heat. A moldable cork sheet, therefore, was established as a realistic product.

  7. LIST OF INSTRUCTIONAL MATERIALS.

    ERIC Educational Resources Information Center

    Tennessee State Dept. of Education, Nashville.

    PRICES ARE GIVEN FOR MATERIALS FOR AGRICULTURE EDUCATION, HEALTH OCCUPATIONS EDUCATION, DISTRIBUTIVE EDUCATION, MANPOWER DEVELOPMENT AND TRAINING PROGRAMS, AND TRADE AND INDUSTRIAL EDUCATION. THESE INCLUDE COURSES OF STUDY, LESSON PLANS, TEST AND ANSWER BOOKLETS, ASSIGNMENT SHEETS, AND TEACHER HANDBOOKS. (EL)

  8. Quasicrystals: Making invisible materials

    NASA Astrophysics Data System (ADS)

    Boriskina, Svetlana V.

    2015-07-01

    All-dielectric photonic quasicrystals may act as zero-refractive-index homogeneous materials despite their lack of translational symmetry and periodicity, stretching wavelengths to infinity and offering applications in light wavefront sculpting and optical cloaking.

  9. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1984-01-01

    Progress is reported in studies of constituent materials composite materials, generic structural elements, processing science technology, and maintaining long-term structural integrity. Topics discussed include: mechanical properties of high performance carbon fibers; fatigue in composite materials; experimental and theoretical studies of moisture and temperature effects on the mechanical properties of graphite-epoxy laminates and neat resins; numerical investigations of the micromechanics of composite fracture; delamination failures of composite laminates; effect of notch size on composite laminates; improved beam theory for anisotropic materials; variation of resin properties through the thickness of cured samples; numerical analysis composite processing; heat treatment of metal matrix composites, and the RP-1 and RP2 gliders of the sailplane project.

  10. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1982-01-01

    The promise of filamentary composite materials, whose development may be considered as entering its second generation, continues to generate intense interest and applications activity. Fiber reinforced composite materials offer substantially improved performance and potentially lower costs for aerospace hardware. Much progress has been achieved since the initial developments in the mid 1960's. Rather limited applications to primary aircraft structure have been made, however, mainly in a material-substitution mode on military aircraft, except for a few experiments currently underway on large passenger airplanes in commercial operation. To fulfill the promise of composite materials completely requires a strong technology base. NASA and AFOSR recognize the present state of the art to be such that to fully exploit composites in sophisticated aerospace structures, the technology base must be improved. This, in turn, calls for expanding fundamental knowledge and the means by which it can be successfully applied in design and manufacture.

  11. Wth Basic Art Materials

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    2010-01-01

    In this article, the author presents a checklist of basic materials for two-dimensional activities that are necessary for an elementary-school art program. She also provides a few tips on how to use them.

  12. Developments in carbon materials

    NASA Technical Reports Server (NTRS)

    Burchell, Timothy D.

    1994-01-01

    The following carbon-based materials are reviewed and their applications discussed: fullerenes; graphite (synthetic and manufactured); activated carbon fibers; and carbon-carbon composites. Carbon R&D activities at ORNL are emphasized.

  13. Nano-composite materials

    DOEpatents

    Lee, Se-Hee; Tracy, C. Edwin; Pitts, J. Roland

    2010-05-25

    Nano-composite materials are disclosed. An exemplary method of producing a nano-composite material may comprise co-sputtering a transition metal and a refractory metal in a reactive atmosphere. The method may also comprise co-depositing a transition metal and a refractory metal composite structure on a substrate. The method may further comprise thermally annealing the deposited transition metal and refractory metal composite structure in a reactive atmosphere.

  14. Concise polymeric materials encyclopedia

    SciTech Connect

    Salamone, J.C.

    1999-01-01

    This comprehensive, accessible resource abridges the ``Polymeric Materials Encyclopedia'', presenting more than 1,100 articles and featuring contributions from more than 1,800 scientists from all over the world. The text discusses a vast array of subjects related to the: (1) synthesis, properties, and applications of polymeric materials; (2) development of modern catalysts in preparing new or modified polymers; (3) modification of existing polymers by chemical and physical processes; and (4) biologically oriented polymers.

  15. Ceramic Laser Materials

    SciTech Connect

    Soules, T F; Clapsaddle, B J; Landingham, R L; Schaffers, K I

    2005-02-15

    Transparent ceramic materials have several major advantages over single crystals in laser applications, not the least of which is the ability to make large aperture parts in a robust manufacturing process. After more than a decade of working on making transparent YAG:Nd, Japanese workers have recently succeeded in demonstrating samples that performed as laser gain media as well as their single crystal counterparts. Since then several laser materials have been made and evaluated. For these reasons, developing ceramic laser materials is the most exciting and futuristic materials topic in today's major solid-state laser conferences. We have established a good working relationship with Konoshima Ltd., the Japanese producer of the best ceramic laser materials, and have procured and evaluated slabs designed by us for use in our high-powered SSHCL. Our measurements indicate that these materials will work in the SSHCL, and we have nearly completed retrofitting the SSHCL with four of the largest transparent ceramic YAG:Nd slabs in existence. We have also begun our own effort to make this material and have produced samples with various degrees of transparency/translucency. We are in the process of carrying out an extensive design-of-experiments to establish the significant process variables for making transparent YAG. Finally because transparent ceramics afford much greater flexibility in the design of lasers, we have been exploring the potential for much larger apertures, new materials, for example for the Mercury laser, other designs for SSHL, such as, edge pumping designs, slabs with built in ASE suppression, etc. This work has just beginning.

  16. NMR imaging of materials

    SciTech Connect

    Vinegar, H.J.; Rothwell, W.P.

    1988-03-01

    A method for obtaining at least one petrophysical property of a porous material containing therein at least one preselected fluid, is described, comprising: NMR imaging the material to generate signals dependent upon both M(0) and T/sub 1/ and M(0) and T/sub 2/, generating separate M(0), T/sub 1/ and T/sub 2/ images from the signals, and determining at least one petrophysical property from at least one of the images.

  17. Food Packaging Materials

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The photos show a few of the food products packaged in Alure, a metallized plastic material developed and manufactured by St. Regis Paper Company's Flexible Packaging Division, Dallas, Texas. The material incorporates a metallized film originally developed for space applications. Among the suppliers of the film to St. Regis is King-Seeley Thermos Company, Winchester, Ma'ssachusetts. Initially used by NASA as a signal-bouncing reflective coating for the Echo 1 communications satellite, the film was developed by a company later absorbed by King-Seeley. The metallized film was also used as insulating material for components of a number of other spacecraft. St. Regis developed Alure to meet a multiple packaging material need: good eye appeal, product protection for long periods and the ability to be used successfully on a wide variety of food packaging equipment. When the cost of aluminum foil skyrocketed, packagers sought substitute metallized materials but experiments with a number of them uncovered problems; some were too expensive, some did not adequately protect the product, some were difficult for the machinery to handle. Alure offers a solution. St. Regis created Alure by sandwiching the metallized film between layers of plastics. The resulting laminated metallized material has the superior eye appeal of foil but is less expensive and more easily machined. Alure effectively blocks out light, moisture and oxygen and therefore gives the packaged food long shelf life. A major packaging firm conducted its own tests of the material and confirmed the advantages of machinability and shelf life, adding that it runs faster on machines than materials used in the past and it decreases product waste; the net effect is increased productivity.

  18. Nonmetallic Materials Handbook

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A handbook compilation of chemical and physical property tests data obtained during qualification and receiving inspection testing of nonmetallic materials for the Viking Lander is introduced. Data cover the following materials: sealants, potting compounds, lubricants, paints and finishes, inks, films, encapsulants, elastomers, structural plastics, ablatives, adhesives, and electrical and thermal insulation. Thermochemical data showing degradation as a function of temperature, from room to 500 C, are included.

  19. Multifunctional nanocomposite materials

    SciTech Connect

    Roy, R.; Komarneni, S.

    1991-11-01

    Objective is to examine the low temperature nanocomposite route in the synthesis of multifunctional materials using two-dimensional clays as hosts. After about 8 months, a significant advance was made in the design and synthesis of novel nanocomposite materials, which are nanometal intercalated clays prepared by a low temperature route. A layered V[sub 2]O[sub 5] gel has been made hydrothermally and its cation exchange properties measured. Several pillared clays have also been synthesized and characterized.

  20. Beam-Material Interaction

    SciTech Connect

    Mokhov, N. V.; Cerutti, F.

    2016-01-01

    Th is paper is motivated by the growing importance of better understanding of the phenomena and consequences of high-intensity energetic particle beam interactions with accelerator, generic target, and detector components. It reviews the principal physical processes of fast-particle interactions with matter, effects in materials under irradiation, materials response, related to component lifetime and performance, simulation techniques, and methods of mitigating the impact of radiation on the components and environment in challenging current and future applications.

  1. USGS reference materials

    USGS Publications Warehouse

    ,

    1995-01-01

    Every year in the United States, millions of measurements are made on the chemical composition of items that affect us on a daily basis. Determining the accuracy of these measurements is based on the analysis of appropriate reference materials whose composition was previously determined through rigorous testing. Today, reference materials help us evaluate the composition of the food we eat, medicine we use, soil we grow our crops in, and hundreds of other products that affect our everyday lives.

  2. Container for radioactive materials

    DOEpatents

    Fields, Stanley R.

    1985-01-01

    A container for housing a plurality of canister assemblies containing radioactive material and disposed in a longitudinally spaced relation within a carrier to form a payload package concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and a sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path.

  3. Noise Abatement Materials

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A former NASA employee who discovered a kind of plastic that soaked up energy, dampened vibrations, and was a good noise abatement material, founded a company to market noise deadening adhesives, sheets, panels and enclosures. Known as SMART products, they are 75-80% lighter than ordinary soundproofing material and have demonstrated a high degree of effectiveness. The company, Varian Associates, makes enclosures for high voltage terminals and other electronic system components, and easily transportable audiometric test booths.

  4. Computerized material accounting

    SciTech Connect

    Claborn, J.; Erkkila, B.

    1995-07-01

    With the advent of fast, reliable database servers running on inexpensive networked personal computers, it is possible to create material accountability systems that are easy to learn, easy to use, and cost-effective to implement. Maintaining the material data in a relational database allows data to be viewed in ways that were previously very difficult. This paper describes a software and hardware platforms for the implementation of such an accountability system.

  5. Biomimetic Hydrogel Materials

    DOEpatents

    Bertozzi, Carolyn , Mukkamala, Ravindranath , Chen, Oing , Hu, Hopin , Baude, Dominique

    2003-04-22

    Novel biomimetic hydrogel materials and methods for their preparation. Hydrogels containing acrylamide-functionalized carbohydrate, sulfoxide, sulfide or sulfone copolymerized with a hydrophilic or hydrophobic copolymerizing material selected from the group consisting of an acrylamide, methacrylamide, acrylate, methacrylate, vinyl and a derivative thereof present in concentration from about 1 to about 99 wt %. and methods for their preparation. The method of use of the new hydrogels for fabrication of soft contact lenses and biomedical implants.

  6. Biomimetic hydrogel materials

    DOEpatents

    Bertozzi, Carolyn; Mukkamala, Ravindranath; Chen, Qing; Hu, Hopin; Baude, Dominique

    2000-01-01

    Novel biomimetic hydrogel materials and methods for their preparation. Hydrogels containing acrylamide-functionalized carbohydrate, sulfoxide, sulfide or sulfone copolymerized with a hydrophilic or hydrophobic copolymerizing material selected from the group consisting of an acrylamide, methacrylamide, acrylate, methacrylate, vinyl and a derivative thereof present in concentration from about 1 to about 99 wt %. and methods for their preparation. The method of use of the new hydrogels for fabrication of soft contact lenses and biomedical implants.

  7. La place du clou Telegraph court dans le traitement des fractures de l'extrémité supérieure de l'humérus: à propos de 19 cas

    PubMed Central

    karabila, Mohamed Amine; Hmouri, Ismail; Mhamdi, Younes; Azouz, Mohamed; Madani, Tarik; Kharmaz, Mohamed; Ouadaghiri, Mohamed; Lamrani, Moulay Omar; Bardouni, Ahmed; Lahlou, Abdou; Mahfoud, Mustapha; Berrada, Mohamed Saleh; Montbarbon, Éric; Beaudouin, Emmanuel

    2016-01-01

    La fracture de l'extrémité supérieure de l'humérus est la troisième fracture en fréquence chez les sujets âgés et leur répartition est bimodale touchant préférentiellement le sujet âgé ostéoporotique après un traumatisme à faible énergie ou plus rarement le sujet jeune par mécanisme à forte cinétique. Le traitement des fractures complexes de l'humérus proximal est le sujet de nombreuses controverses Le clou Telegraph constitue une approche thérapeutique très efficace pour les fractures déplacées de l'extrémité supérieure de l'humérus, de technique chirurgicale facile mais avec une courbe d'apprentissage et permettant un protocole de rééducation dans l'immédiat de l'intervention. C'est un matériel d'enclouage antérograde de 15 cm de long, plein verrouillé en proximal et en distal, le verrouillage proximal est assuré par 4 vis spongieuses, de filetage long, stables dans le clou et cela confère une solidité tout-à-fait remarquable à ce montage alors que le verrouillage distal est assuré au niveau du V deltoïdien en zone avasculaire et là où il n'y a pas de passage nerveux. L’étude présentée concerne 19 patients traités par un clou Telegraph court dans le traitement des fractures de l'extrémité supérieure de l'humérus entre 2013 et 2015 et elle a pour but d'analyser les résultats radio-cliniques et d’évaluer la répercussion de cette technique sur la fonction de l’épaule. Le clou Telegraph proposé depuis plus de 12 ans à peu près, a rencontré et continue de rencontrer un réel succès. Il permet de traiter très efficacement les fractures simples type 2 et 3, mais aussi les fractures impactées en valgus à 4 fragments. L'ostéosynthèse par clou Telegraph est une solution efficace, rapide et reproductible dans le traitement chirurgical des fractures de l'extrémité supérieur de l'humérus même en cas des fractures complexes et permet une reprise rapide de la mobilité de l’épaule. PMID:27583100

  8. LDEF materials data bases

    NASA Technical Reports Server (NTRS)

    Funk, Joan G.; Strickland, John W.; Davis, John M.

    1993-01-01

    The Long Duration Exposure Facility (LDEF) and the accompanying experiments were composed of and contained a wide variety of materials representing the largest collection of materials flown in low Earth orbit (LEO) and retrieved for ground based analysis to date. The results and implications of the mechanical, thermal, optical, and electrical data from these materials are the foundation on which future LEO space missions will be built. The LDEF Materials Special Investigation Group (MSIG) has been charged with establishing and developing data bases to document these materials and their performance to assure not only that the data are archived for future generations but also that the data are available to the spacecraft user community in an easily accessed, user-friendly form. This paper discusses the format and content of the three data bases developed or being developed to accomplish this task. The hardware and software requirements for each of these three data bases are discussed along with current availability of the data bases. This paper also serves as a user's guide to the MAPTIS LDEF Materials Data Base.

  9. Superconducting materials processing

    NASA Technical Reports Server (NTRS)

    Hurley, John S.; Karikari, Emmanuel K.; Hiamang, S. O.; Danjaji, M.; Bassey, Affiong; Morgan, Andre

    1995-01-01

    The effects of materials processing on the properties and behavior of high temperature yttrium barium copper oxide (YBCO) superconductors were investigated. Electrical, magnetic, and structural characteristics of thin films (300 nm) YBA2CU3O(delta) structures grown by pulsed laser deposition on LaAlO3 and SrTiO3 substrates were used to evaluate processing. Pole projection and thin film diffraction measurements were used to establish grain orientation and verify structural integrity of the samples. Susceptibility magnetization, and transport measurements were used to evaluate the magnetic and electrical transport properties of the samples. Our results verified that an unfortunate consequence of processing is inherent changes to the internal structure of the material. This effect translates into modifications in the properties of the materials, and undesired feature that makes it very difficult to consistently predict material behavior. The results show that processing evaluation must incorporate a comprehensive understanding of the properties of the materials. Future studies will emphasize microstructural characteristics of the materials, in particular, those microscopic properties that map macroscopic behavior.

  10. Nano-scale materials

    SciTech Connect

    Barrera, J.; Smith, D.C.; Devlin, D.J.

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Highly selective, alumina-supported molybdenum carbonitrides were prepared by solution impregnation using the metal amide Mo{sub 2}(N(CH{sub 3}){sub 2}){sub 6} as a molecular precursor. On the basis of relative weight percents, these materials demonstrate a 5- to 8-fold increase in catalytic activity over similar materials prepared by traditional solid-state approaches. The catalytic activities of these materials are very dependent upon the type of alumina support used. Impregnation of Mo{sub m}C{sub x}N{sub y} into preformed alumina pellets resulted in a material that specifically isomerized n-heptane into equal amounts of 2- and 3-methylhexanes, as well as iso-butane. No evidence of aromatic products was observed at operating temperatures below 420{degrees}C. The product selectivity of the isomers was 56% at a n-heptane conversion efficiency of 57%. Impregnating Mo{sub m}C{sub x}N{sub y} into an alumina powder resulted in an extremely selective aromatized and dehydrogenated material. The products from this material consist only of aromatics and n-heptenes with less than 2% isomerization or cracking products.

  11. Nuclear Material Management Abstract

    SciTech Connect

    Jesse C. Schreiber

    2007-07-10

    Nevada Test Site (NTS) has transitioned from its historical and critical role of weapons testing to another critical role for the nation. This new role focuses on being a integral element in solving the multiple challenges facing the National Nuclear Security Administration (NNSA) with nuclear material management. NTS is positioned to be a solution for other NNSA sites challenged with safe nuclear materials storage and disposition. NNSA, with site involvement, is currently transforming the nuclear stockpile and supporting infrastructure to meet the 2030 vision. Efforts are under way to consolidate and modernize the production complex . With respect to the nuclear material stockpile, the NNSA sites are currently reducing the complex nuclear material inventory through disposition and consolidation. This includes moving material from other sites to NTS. State of the art nuclear material management and control practices at NTS are essential for NTS to ensure that assigned activities are accomplished in a safe, secure, efficient, and environmentally responsible manner. NTS activities and challenges will be addressed.

  12. EDITORIAL: Materially speaking!

    NASA Astrophysics Data System (ADS)

    Cornwall, Malcolm G.

    1997-05-01

    We live in a highly materialistic age. This is true not only for our spiritual outlook - or lack of it - but undeniably so for the physical world in which we live. Materials, which are the feature of this special issue, provide literally the fabric on which the modern world is built. Materials science is the systematic study of the physical properties and behaviour of solids with practical applications and importance (if the utility of the material is not explicit or important we are probably in the realm of solid state physics!). Materials in this sense are the stuff of which cars and computers, jet aircraft and washing machines, tower blocks and saucepans, bridges and golf clubs are made. The science of materials therefore encompasses most of the things that form the infrastructure of modern life. But perhaps it is its very ubiquity that removes the mystique, the glamour, the 'zing' from the subject. In contrast, anything cosmological, astronomical or 'fundamental' (as in 'particle'), i.e. of little or no practical significance to our day-to-day lives, excites the curiosity of many able young people. Witness the profusion of books about galaxies and black holes, and quarks and GUTs which strain the popular science shelves of the bookshops. I'm probably being heretical, but perhaps the over-hyping of the very large and the very small has indeed attracted the able few into the serious study of physics, but because of its inherent mathematical complexity and esoteric remoteness maybe it has put off the average youngster who would nevertheless enjoy and succeed in physics-based higher education (and, not incidentally, help fill the seriously depleted lecture theatres in many university physics - and engineering - departments). Materials science on the other hand deals with an intermediate range of things which, give or take an order of magnitude or three, are person-sized as well as person useful. It is - therefore? - undoubtedly one of the less glamorous of the

  13. Tribological comparison of materials

    NASA Astrophysics Data System (ADS)

    Shi, Bing

    Approximately 600,000 total joint replacement surgeries are performed each year in the United States. Current artificial joint implants are mainly metal-on-plastic. The synthetic biomaterials undergo degradation through fatigue and corrosive wear from load-bearing and the aqueous ionic environment of the human body. Deposits of inorganic salts can scratch weight-bearing surfaces, making artificial joints stiff and awkward. The excessive wear debris from polyethylene leads to osteolysis and potential loosening of the prosthesis. The lifetime for well-designed artificial joints is at most 10 to 15 years. A patient can usually have two total joint replacements during her/his lifetime. Durability is limited by the body's reaction to wear debris of the artificial joints. Wear of the artificial joints should be reduced. A focus of this thesis is the tribological performance of bearing materials for Total Replacement Artificial Joints (TRAJ). An additional focus is the scaffolds for cell growth from both a tissue engineering and tribological perspective. The tribological properties of materials including Diamond-like Carbon (DLC) coated materials were tested for TRAJ implants. The DLC coatings are chemically inert, impervious to acid and saline media, and are mechanically hard. Carbon-based materials are highly biocompatible. A new alternative to total joints implantation is tissue engineering. Tissue engineering is the replacement of living tissue with tissue that is designed and constructed to meet the needs of the individual patient. Cells were cultured onto the artificial materials, including metals, ceramics, and polymers, and the frictional properties of these materials were investigated to develop a synthetic alternative to orthopedic transplants. Results showed that DLC coated materials had low friction and wear, which are desirable tribological properties for artificial joint material. Cells grew on some of the artificial matrix materials, depending on the

  14. Catalog of Martian Materials

    NASA Astrophysics Data System (ADS)

    Newsom, Horton E.; Hagerty, J. J.

    1998-01-01

    The long-term exploration of Mars will require the utilization of surface and near-surface materials for construction, radiation shielding, and life support. Eventually, such materials could be used as raw materials in manufacturing. While there is a resemblance between the surface of Mars, as revealed in Viking and Pathfinder images, and terrestrial desert environments, there are distinct differences that will affect the utilization of in situ resources. In general, the surface geological features are extremely old compared to Earth, dating back to the early evolution of the solar system. Therefore, materials created by processes such as impact cratering are important on Mars. Impact cratering probably created extensive sheets of impact melt bearing breccias on the surface and resulted in the formation of a thick regolith of broken rock fragments in the ancient terrains of Mars. Another key feature is the lack of rainfall over most of Mars' history. This resulted in the lack of extensive erosion. On Earth, extensive erosion of volcanic centers, for example, has exposed deep hydrothermal deposits that are mined for Cu, Mo, and W, but such deposits are not likely to be exposed at the surface on Mars. Similarly, deposits of quartz sand, used for glass making, are created by the erosion of granitic terrains on Earth, and are not likely to be found on Mars. The soil on Mars is also very different from wind-blown material on Earth. Virtually no organic material is present, and the material is enriched in volatile elements, such as S and Cl, and possibly also toxic heavy metals, derived from volcanic gases and hydrothermal waters that poured onto the surface. The volatile elements have remained in the soil due to the absence of processes that recycle volatile elements back into the planet's crust. Hydrogen peroxide originally formed in the atmosphere is also mixed into the soil and regolith, and was probably responsible for the "oxidant" found in the soil by the Viking

  15. Thermodynamics of Thermoelectric Materials

    NASA Astrophysics Data System (ADS)

    Doak, Jeff W.

    One challenge facing society is the responsible use of our energy resources. Increasing the efficiency of energy generation provides one path to solving this challenge. One commonality among most current energy generation methods is that waste heat is generated during the generation process. Thermoelectrics can provide a solution to increasing the efficiency of power generation and automotive systems by converting waste heat directly to electricity. The current barrier to implementation of thermoelectric systems is the low efficiencies of underlying thermoelectric materials. The efficiency of a thermoelectric material depends on the electronic and thermal transport properties of the material; a good thermoelectric material should be an electronic conductor and a thermal insulator, traits which generally oppose one another. The thermal properties of a thermoelectric material can be improved by forming nanoscale precipitates with the material which scatter phonons, reducing the thermal conductivity. The electronic properties of a thermoelectric material can be improved by doping the material to increase the electronic conductivity or by alloying the material to favorably alter its band structure. The ability of these chemical modifications to affect the thermoelectric efficiency of material are ultimately governed by the chemical thermodynamics of the system. PbTe is a prototypical thermoelectric material: Alloying PbTe with PbS (or other materials) creates nanostructures which scatter phonons and reduce the lattice thermal conductivity. Doping PbTe with Na increases the hole concentration, increasing the electronic conductivity. In this work, we investigate the thermodynamics of PbTe and similar systems using first principles to understand the underlying mechanisms controlling the formation of nanostructures and the amount of doping allowed in these systems. In this work we: 1) investigate the thermodynamics of pseudo-binary alloys of IV--VI systems to identify the

  16. Microwave impregnation of porous materials with thermal energy storage materials

    DOEpatents

    Benson, David K.; Burrows, Richard W.

    1993-01-01

    A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

  17. Microwave impregnation of porous materials with thermal energy storage materials

    DOEpatents

    Benson, D.K.; Burrows, R.W.

    1993-04-13

    A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

  18. Microwave impregnation of porous materials with thermal energy storage materials

    SciTech Connect

    Benson, D.K.; Burrows, R.W.

    1991-03-13

    A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent tc the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

  19. Microwave impregnation of porous materials with thermal energy storage materials

    SciTech Connect

    Benson, D.K.; Burrows, R.W.

    1992-12-31

    A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

  20. ATS materials support

    SciTech Connect

    Karnitz, M.A.; Wright, I.G.; Ferber, M.K.; Holcomb, R.S.; Rawlins, M.H.

    1996-12-31

    The technology based portion of the Advanced Turbine System Program (ATS) contains several subelements which address generic technology issues for land-base gas turbine systems. One subelement is the Materials/Manufacturing Technology Program which is coordinated by DOE-Oak Ridge Operations and Oak Ridge National laboratory (ORNL) for the Department of Energy. The work in this subelement is being performed predominantly by industry with assistance from national laboratories and universities. Projects in this subelement are aimed toward hastening the incorporation of new materials and components in gas turbines. The materials manufacturing subelement was developed with input from gas turbine manufacturers, material suppliers, government laboratories and universities. Work is currently ongoing on thermal barrier coatings (TBCs), the scale-up of single-crystal airfoil manufacturing technologies, materials characterization and technology information exchange. Westinghouse Power Generation and Pratt and Whitney each have material programs to develop dependable TBCs that enable increased turbine inlet temperatures while maintaining airfoil substrate temperatures at levels to meet the ATS life goals. Howmet and PCC Airfoils each have projects to extend the capability of single-crystal complex-cored airfoil technology to larger sizes so that higher turbine inlet temperatures can be attained in land-based turbines in a cost-effective manner. Materials characterization tasks are ongoing on TBCs in support of the industrial projects. In addition, a project on long-term testing of ceramics and ceramic-matrix composites for gas turbines is being conducted in support of programs at Solar Turbines, Allison Engines, and Westinghouse Power Generation.

  1. BUILDING MATERIALS RECLAMATION PROGRAM

    SciTech Connect

    David C. Weggel; Shen-En Chen; Helene Hilger; Fabien Besnard; Tara Cavalline; Brett Tempest; Adam Alvey; Madeleine Grimmer; Rebecca Turner

    2010-08-31

    This report describes work conducted on the Building Materials Reclamation Program for the period of September 2008 to August 2010. The goals of the project included selecting materials from the local construction and demolition (C&D) waste stream and developing economically viable reprocessing, reuse or recycling schemes to divert them from landfill storage. Educational resources as well as conceptual designs and engineering feasibility demonstrations were provided for various aspects of the work. The project was divided into two distinct phases: Research and Engineering Feasibility and Dissemination. In the Research Phase, a literature review was initiated and data collection commenced, an advisory panel was organized, and research was conducted to evaluate high volume C&D materials for nontraditional use; five materials were selected for more detailed investigations. In the Engineering Feasibility and Dissemination Phase, a conceptual study for a regional (Mecklenburg and surrounding counties) collection and sorting facility was performed, an engineering feasibility project to demonstrate the viability of recycling or reuse schemes was created, the literature review was extended and completed, and pedagogical materials were developed. Over the two-year duration of the project, all of the tasks and subtasks outlined in the original project proposal have been completed. The Final Progress Report, which briefly describes actual project accomplishments versus the tasks/subtasks of the original project proposal, is included in Appendix A of this report. This report describes the scientific/technical aspects (hypotheses, research/testing, and findings) of six subprojects that investigated five common C&D materials. Table 1 summarizes the six subprojects, including the C&D material studied and the graduate student and the faculty advisor on each subproject.

  2. [Elastomeric impression materials].

    PubMed

    Levartovsky, S; Folkman, M; Alter, E; Pilo, R

    2011-04-01

    Elastomeric impression materials are in common use. The impression taken should be highly precise, thus, requiring specific care when manipulatingthese materials. There are 4 groups of elastomers; polysulfide, condensation silicone, addition silicone and polyether; each differ in their setting mechanism and their physical and chemical properties. This review elaborates the major properties of elastomers and its implications on their use. The impression material is inserted into the patient's mouth in a viscous state and transforms into viscoelastic state, upon withdrawal, influencing the residual deformation. The requirements are minimal residual deformation or maximal elastic recovery. As the mouth is a wet environment a major consideration is hydrophilicity. The wettability which is estimated by measuring either the contact angle of a droplet of water and the substrate post setting or the contact angle of a droplet of impression material and the wet tooth pre setting, determines the interaction of the material with both mouth fluids and gypsum. As the primary end target is to obtain a model depicting accurately the oral details, an attention to the impressions' compatibility with gypsum should also be given. Many studies were conducted to get a thorough understanding of the hydrophilic properties of each material, and the mechanism utilized, such as surfactants in hydrophilic PVS. Polyether is the only material that is truly hydrophilic; it exhibits the lowest contact angle, during and after setting. Recent studies show that during setting the Polyether hydrophilicity is increased compared to the condition after setting. Dimensional stability, a crucial property of the impression, is affected by the physical and chemical attributes of the material, such as its tear strength. Polysulfide has the highest tear strength. Tear Strength is affected by two major parameters, viscosity, a built-in property, and how fast the impression is pulled out of the mouth, the

  3. Nanostructured materials in potentiometry.

    PubMed

    Düzgün, Ali; Zelada-Guillén, Gustavo A; Crespo, Gastón A; Macho, Santiago; Riu, Jordi; Rius, F Xavier

    2011-01-01

    Potentiometry is a very simple electrochemical technique with extraordinary analytical capabilities. It is also well known that nanostructured materials display properties which they do not show in the bulk phase. The combination of the two fields of potentiometry and nanomaterials is therefore a promising area of research and development. In this report, we explain the fundamentals of potentiometric devices that incorporate nanostructured materials and we highlight the advantages and drawbacks of combining nanomaterials and potentiometry. The paper provides an overview of the role of nanostructured materials in the two commonest potentiometric sensors: field-effect transistors and ion-selective electrodes. Additionally, we provide a few recent examples of new potentiometric sensors that are based on receptors immobilized directly onto the nanostructured material surface. Moreover, we summarize the use of potentiometry to analyze processes involving nanostructured materials and the prospects that the use of nanopores offer to potentiometry. Finally, we discuss several difficulties that currently hinder developments in the field and some future trends that will extend potentiometry into new analytical areas such as biology and medicine.

  4. New microwave coupler material

    SciTech Connect

    Holcombe, C.E.

    1983-12-01

    The unexpected coupling of urania (UO/sub x/, with 2 less than or equal to x less than or equal to 3) to microwave energy has previously been reported. The present study screened several different materials for coupling with microwave energy using a 1.6 kW, 2450 MHz system. Materials were nominally -100 mesh powder, >99% pure. Those which showed minimal or no heating with the microwave energy included Y/sub 2/O/sub 3/, Al/sub 2/O/sub 3/, SiO/sub 2/, BN, graphite, and unstabilized ZrO/sub 2/. Pronounced heating occurred with B/sub 4/C. This discovery led to the following evaluation/comparison of the coupling ability of B/sub 4/C with water, structurally similar materials (boron suboxide, B/sub 6/O - prepared from zinc oxide and boron, microcrystalline or amorphous boron, ..cap alpha..-type), and UO/sub 2/. In order to compare relative heating rates, the materials were placed into 50 mL beakers, covered with alumina-silica felt insulation, and subjected to 30 s at full power (both top and bottom sources on). The temperature was measured at the end of the test, after the door automatically opened, by inserting a type K thermocouple into the material. For the powders, the thermocouple was moved about to obtain the highest reading, although only a 10% or so variation occurred before the temperature dropped from heat losses. 4 references, 1 table.

  5. Material bagging device

    DOEpatents

    Wach, Charles G.; Nelson, Robert E.; Brak, Stephen B.

    1984-01-01

    A bagging device for transferring material from one chamber through an opening in a wall to a second chamber includes a cylindrical housing communicating with the opening and defining a passage between the chambers. A cylindrical cartridge is slidably received within the housing. The cartridge has a substantially rigid cylindrical sleeve to which is affixed a pliable tube. The pliable tube is positioned concentrically about the sleeve and has a pleated portion capable of unfolding from the sleeve and a closed end extending over a terminal end of the sleeve. Sealing means are interposed in sealed relationship between the cartridge and the housing. Material from one chamber is inserted into the cartridge secured in the housing and received in the closed end of the tube which unfolds into the other chamber enclosing the material therein. The tube may then be sealed behind the material and then severed to form a bag-like enclosure defined by the tube's closed terminal end and the new seal. The new seal then forms a terminal end for the unsevered portion of the pliable tube into which additional material may be placed and the bagging process repeated.

  6. Astrophysics with Extraterrestrial Materials

    NASA Astrophysics Data System (ADS)

    Nittler, Larry R.; Ciesla, Fred

    2016-09-01

    Extraterrestrial materials, including meteorites, interplanetary dust, and spacecraft-returned asteroidal and cometary samples, provide a record of the starting materials and early evolution of the Solar System. We review how laboratory analyses of these materials provide unique information, complementary to astronomical observations, about a wide variety of stellar, interstellar and protoplanetary processes. Presolar stardust grains retain the isotopic compositions of their stellar sources, mainly asymptotic giant branch stars and Type II supernovae. They serve as direct probes of nucleosynthetic and dust formation processes in stars, galactic chemical evolution, and interstellar dust processing. Extinct radioactivities suggest that the Sun's birth environment was decoupled from average galactic nucleosynthesis for some tens to hundreds of Myr but was enriched in short-lived isotopes from massive stellar winds or explosions shortly before or during formation of the Solar System. Radiometric dating of meteorite components tells us about the timing and duration over which solar nebula solids were assembled into the building blocks of the planets. Components of the most primitive meteoritical materials provide further detailed constraints on the formation, processing, and transport of material and associated timescales in the Sun's protoplanetary disk as well as in other forming planetary systems.

  7. Panel 3 - material science

    SciTech Connect

    Sarrao, John L; Yip, Sidney

    2010-01-01

    In the last decades, NNSA's national security challenge has evolved, and the role of simulation and computation has grown dramatically. The process of certifying nuclear weapons performance has changed from one based on integrated tests to science-based certification in which underground nuclear tests have been replaced by large-scale simulations, appropriately validated with fundamental experimental data. Further, the breadth of national security challenges has expanded beyond stewardship of a nuclear deterrent to a broad range of global and asymmetric threats. Materials challenges are central to the full suite of these national security challenges. Mission requirements demand that materials perform predictably in extreme environments -- high pressure, high strain rate, and hostile irradiation and chemical conditions. Considerable advances have been made in incorporating fundamental materials physics into integrated codes used for component certification. On the other hand, significant uncertainties still remain, and materials properties, especially at the mesoscale, are key to understanding uncertainties that remain in integrated weapons performance codes and that at present are treated as empirical knobs. Further, additional national security mission challenges could be addressed more robustly with new and higher performing materials.

  8. A Material Conferring Hemocompatibility

    PubMed Central

    Everett, William; Scurr, David J; Rammou, Anna; Darbyshire, Arnold; Hamilton, George; de Mel, Achala

    2016-01-01

    There is a need for biomimetic materials for use in blood-contacting devices. Blood contacting surfaces maintain their patency through physico-chemical properties of a functional endothelium. A poly(carbonate-urea) urethane (PCU) is used as a base material to examine the feasibility of L-Arginine methyl ester (L-AME) functionalized material for use in implants and coatings. The study hypothesizes that L-AME, incorporated into PCU, functions as a bioactive porogen, releasing upon contact with blood to interact with endothelial nitric oxide synthase (eNOS) present in blood. Endothelial progenitor cells (EPC) were successfully cultured on L-AME functionalized material, indicating that L-AME -increases cell viability. L-AME functionalized material potentially has broad applications in blood-contacting medical devices, as well as various other applications requiring endogenous up-regulation of nitric oxide, such as wound healing. This study presents an in-vitro investigation to demonstrate the novel anti-thrombogenic properties of L-AME, when in solution and when present within a polyurethane-based polymer. PMID:27264087

  9. Dynamic Strength of Materials

    NASA Astrophysics Data System (ADS)

    Chhabildas, Lalit

    2011-06-01

    Historically when shock loading techniques became accessible in the early fifties it was assumed that materials behave like fluids implying that materials cannot support any shear stresses. Early and careful investigation in the sixties by G. R. Fowles in aluminum indicated otherwise. When he compared his Hugoniot compression measurements to hydrostatic pressure compression measurements in the pressure volume plane he noticed that the shock data lay above the hydrostatic compression curve - which laid the ground work for what is the basis for elastic-plastic theories that exist today. In this talk, a brief historical perspective on strength measurements in materials will be discussed including how time-resolved techniques have played a role in allowing estimates of the strength of materials at over Mbar stress. This is crucial especially at high stresses since we are determining values that are small compared to the loading stress. Even though we have made considerable progress in our understanding of materials, there are still many anomalies and unanswered questions. Some of these anomalies are fertile grounds for further and future research and will be mentioned.

  10. Novel pyroelectric sensor materials.

    PubMed

    Sengupta, S; Sengupta, L C; Synowczynski, J; Rees, D A

    1998-01-01

    Ceramic compositions of barium strontium titanium oxide (BSTO) have been formulated for applications as pyroelectric sensor materials. The material has been fabricated in tape-cast and thin film forms. In general, the materials demonstrated high pyroelectric coefficients (p) accompanied with low dielectric constant and low dissipation factor. The compositions of the tape-cast and thin film specimens examined in this paper include a well-known commercially adopted Ba0.64Sr0.36TiO3 as well as a composition suggested in the literature, and a patented composition with the addition of MgO to BSTO is investigated. Doping BSTO with MgO has been shown to reduce the dielectric constant and loss tangent (over a very wide frequency range from 100 Hz-10 GHz) of the material and thereby increase the pyroelectric figure of merit. This article will discuss the processing, material characterization, pyroelectric coefficient, and pyroelectric figure-of-merit of the above mentioned BSTO compositions.

  11. A Material Conferring Hemocompatibility.

    PubMed

    Everett, William; Scurr, David J; Rammou, Anna; Darbyshire, Arnold; Hamilton, George; de Mel, Achala

    2016-06-06

    There is a need for biomimetic materials for use in blood-contacting devices. Blood contacting surfaces maintain their patency through physico-chemical properties of a functional endothelium. A poly(carbonate-urea) urethane (PCU) is used as a base material to examine the feasibility of L-Arginine methyl ester (L-AME) functionalized material for use in implants and coatings. The study hypothesizes that L-AME, incorporated into PCU, functions as a bioactive porogen, releasing upon contact with blood to interact with endothelial nitric oxide synthase (eNOS) present in blood. Endothelial progenitor cells (EPC) were successfully cultured on L-AME functionalized material, indicating that L-AME -increases cell viability. L-AME functionalized material potentially has broad applications in blood-contacting medical devices, as well as various other applications requiring endogenous up-regulation of nitric oxide, such as wound healing. This study presents an in-vitro investigation to demonstrate the novel anti-thrombogenic properties of L-AME, when in solution and when present within a polyurethane-based polymer.

  12. EDITORIAL: Electroactive polymer materials

    NASA Astrophysics Data System (ADS)

    Bar-Cohen, Yoseph; Kim, Kwang J.; Ryeol Choi, Hyouk; Madden, John D. W.

    2007-04-01

    Imitating nature's mechanisms offers enormous potential for the improvement of our lives and the tools we use. This field of the study and imitation of, and inspiration from, nature's methods, designs and processes is known as biomimetics. Artificial muscles, i.e. electroactive polymers (EAPs), are one of the emerging technologies enabling biomimetics. Polymers that can be stimulated to change shape or size have been known for many years. The activation mechanisms of such polymers include electrical, chemical, pneumatic, optical and magnetic. Electrical excitation is one of the most attractive stimulators able to produce elastic deformation in polymers. The convenience and practicality of electrical stimulation and the continual improvement in capabilities make EAP materials some of the most attractive among activatable polymers (Bar-Cohen Y (ed) 2004 Electroactive Polymer (EAP) Actuators as Artificial Muscles—Reality, Potential and Challenges 2nd edn, vol PM136 (Bellingham, WA: SPIE Press) pp 1-765). As polymers, EAP materials offer many appealing characteristics that include low weight, fracture tolerance and pliability. Furthermore, they can be configured into almost any conceivable shape and their properties can be tailored to suit a broad range of requirements. These capabilities and the significant change of shape or size under electrical stimulation while being able to endure many cycles of actuation are inspiring many potential possibilities for EAP materials among engineers and scientists in many different disciplines. Practitioners in biomimetics are particularly excited about these materials since they can be used to mimic the movements of animals and insects. Potentially, mechanisms actuated by EAPs will enable engineers to create devices previously imaginable only in science fiction. For many years EAP materials received relatively little attention due to their poor actuation capability and the small number of available materials. In the last fifteen

  13. EDITORIAL: Computational materials science Computational materials science

    NASA Astrophysics Data System (ADS)

    Kahl, Gerhard; Kresse, Georg

    2011-10-01

    Special issue in honour of Jürgen Hafner On 30 September 2010, Jürgen Hafner, one of the most prominent and influential members within the solid state community, retired. His remarkably broad scientific oeuvre has made him one of the founding fathers of modern computational materials science: more than 600 scientific publications, numerous contributions to books, and a highly cited monograph, which has become a standard reference in the theory of metals, witness not only the remarkable productivity of Jürgen Hafner but also his impact in theoretical solid state physics. In an effort to duly acknowledge Jürgen Hafner's lasting impact in this field, a Festsymposium was held on 27-29 September 2010 at the Universität Wien. The organizers of this symposium (and authors of this editorial) are proud to say that a large number of highly renowned scientists in theoretical condensed matter theory—co-workers, friends and students—accepted the invitation to this celebration of Hafner's jubilee. Some of these speakers also followed our invitation to submit their contribution to this Festschrift, published in Journal of Physics: Condensed Matter, a journal which Jürgen Hafner served in 2000-2003 and 2003-2006 as a member of the Advisory Editorial Board and member of the Executive Board, respectively. In the subsequent article, Volker Heine, friend and co-worker of Jürgen Hafner over many decades, gives an account of Hafner's impact in the field of theoretical condensed matter physics. Computational materials science contents Theoretical study of structural, mechanical and spectroscopic properties of boehmite (γ-AlOOH) D Tunega, H Pašalić, M H Gerzabek and H Lischka Ethylene epoxidation catalyzed by chlorine-promoted silver oxide M O Ozbek, I Onal and R A Van Santen First-principles study of Cu2ZnSnS4 and the related band offsets for photovoltaic applicationsA Nagoya, R Asahi and G Kresse Renormalization group study of random quantum magnetsIstván A Kovács and

  14. Apparatus for dispensing material

    DOEpatents

    Sutter, Peter Werner; Sutter, Eli Anguelova

    2011-07-05

    An apparatus capable of dispensing drops of material with volumes on the order of zeptoliters is described. In some embodiments of the inventive pipette the size of the droplets so dispensed is determined by the size of a hole, or channel, through a carbon shell encapsulating a reservoir that contains material to be dispensed. The channel may be formed by irradiation with an electron beam or other high-energy beam capable of focusing to a spot size less than about 5 nanometers. In some embodiments, the dispensed droplet remains attached to the pipette by a small thread of material, an atomic scale meniscus, forming a virtually free-standing droplet. In some embodiments the droplet may wet the pipette tip and take on attributes of supported drops. Methods for fabricating and using the pipette are also described.

  15. Bioinspired Functional Materials

    SciTech Connect

    Zheng, Yongmei; Wang, Jingxia; Hou, Yongping; Bai, Hao; Hu, Michael Z.

    2014-11-25

    This special issue is focused on the nanoscale or micro-/nanoscale structures similar to the biological features in multilevels or hierarchy and so on. Research by mimicking biological systems has shown more impact on many applications due to the well-designed micro-/nanostructures inspired from the biological surfaces or interfaces; therefore, the materials may achieve the fascinating functionality. In conclusion, the bioinspired functional materials may be fabricated by developing novel technology or methods such as synthesis, self-assembly, and soft lithography at micro- or nanolevel or multilevels and, in addition, the multidisciplinary procedures of physical or chemical methods and nanotechnology to mimic the biological multiscale micro-/nanostructures onto one-/two-dimensional surface materials.

  16. Material isolation enclosure

    DOEpatents

    Martell, Calvin J.; Dahlby, Joel W.; Gallimore, Bradford F.; Comer, Bob E.; Stone, Water A.; Carlson, David O.

    1993-01-01

    An enclosure similar to a glovebox for isolating materials from the atmosphere, yet allowing a technician to manipulate the materials and also apparatus which is located inside the enclosure. A portion of a wall of the enclosure is comprised of at least one flexible curtain. An opening defined by a frame is provided for the technician to insert his hands and forearms into the enclosure. The frame is movable in one plane, so that the technician has access to substantially all of the working interior of the enclosure. As the frame is moved by the technician, while he accomplishes work inside the enclosure, the curtain moves such that the only opening through the enclosure wall is the frame. In a preferred embodiment, where a negative pressure is maintained inside the enclosure, the frame is comprised of airfoils so that turbulence is reduced, thereby enhancing material retention within the box.

  17. Material isolation enclosure

    DOEpatents

    Martell, C.J.; Dahlby, J.W.; Gallimore, B.F.; Comer, B.E.; Stone, W.A.; Carlson, D.O.

    1993-04-27

    An enclosure is described, similar to a glove box, for isolating materials from the atmosphere, yet allowing a technician to manipulate the materials and also apparatus which is located inside the enclosure. A portion of a wall of the enclosure is comprised of at least one flexible curtain. An opening defined by a frame is provided for the technician to insert his hands and forearms into the enclosure. The frame is movable in one plane, so that the technician has access to substantially all of the working interior of the enclosure. As the frame is moved by the technician, while he accomplishes work inside the enclosure, the curtain moves such that the only opening through the enclosure wall is the frame. In a preferred embodiment, where a negative pressure is maintained inside the enclosure, the frame is comprised of airfoils so that turbulence is reduced, thereby enhancing material retention within the box.

  18. Bioinspired Functional Materials

    DOE PAGESBeta

    Zheng, Yongmei; Wang, Jingxia; Hou, Yongping; Bai, Hao; Hu, Michael Z.

    2014-11-25

    This special issue is focused on the nanoscale or micro-/nanoscale structures similar to the biological features in multilevels or hierarchy and so on. Research by mimicking biological systems has shown more impact on many applications due to the well-designed micro-/nanostructures inspired from the biological surfaces or interfaces; therefore, the materials may achieve the fascinating functionality. In conclusion, the bioinspired functional materials may be fabricated by developing novel technology or methods such as synthesis, self-assembly, and soft lithography at micro- or nanolevel or multilevels and, in addition, the multidisciplinary procedures of physical or chemical methods and nanotechnology to mimic the biologicalmore » multiscale micro-/nanostructures onto one-/two-dimensional surface materials.« less

  19. Fire Resistant Materials

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Fire hazard is greater in atmospheres containing a high percentage of oxygen under pressure. NASA intensified its fire safety research after a 1967 Apollo fire. A chemically treated fabric called Durette developed by Monsanto Company, which will not burn or produce noxious fumes, was selected as a material for Apollo astronaut garments. Monsanto sold production rights for this material to Fire Safe Products (FSP). Durette is now used for a wide range of applications such as: sheets, attendants' uniforms in hyperbaric chambers; crew's clothing, furniture and interior walls of diving chambers operated by the U.S. Navy and other oceanographic companies and research organizations. Pyrotect Safety Equipment, Minneapolis, MN produces Durette suits for auto racers, refuelers and crew chiefs from material supplied by FSP. FSP also manufactures Durette bags for filtering gases and dust from boilers, electric generators and similar systems. Durette bags are an alternative to other felted fiber capable of operating at high temperature that cost twice as much.

  20. Primordial material in meteorites

    NASA Technical Reports Server (NTRS)

    Kerridge, J. F.

    1986-01-01

    Primordial is a term which applied to material that entered the solar system early and became incorporated into a meteorite without totally losing its identity. Identification of such material surviving in meteorites is so far solely through recognition of anomalous isotopic compositions of generally macroscopic entities contained within those meteorites. Isotopic anomalies are, by definition, isotopic compositions which differ from the canonical solar system abundances in ways which cannot be explained in terms of local processes such as mass dependent fractionation, cosmic ray induced spallation or decay of radionuclides. A comprehensive account of isotopic anomalies is impractical here, so it is necessary to be selective. Issues which are potentially addressable through the study of such primordial material are examined. Those issues will be illustrated with specific, but not exhaustive, examples.

  1. Optimized nanoporous materials.

    SciTech Connect

    Braun, Paul V.; Langham, Mary Elizabeth; Jacobs, Benjamin W.; Ong, Markus D.; Narayan, Roger J.; Pierson, Bonnie E.; Gittard, Shaun D.; Robinson, David B.; Ham, Sung-Kyoung; Chae, Weon-Sik; Gough, Dara V.; Wu, Chung-An Max; Ha, Cindy M.; Tran, Kim L.

    2009-09-01

    Nanoporous materials have maximum practical surface areas for electrical charge storage; every point in an electrode is within a few atoms of an interface at which charge can be stored. Metal-electrolyte interfaces make best use of surface area in porous materials. However, ion transport through long, narrow pores is slow. We seek to understand and optimize the tradeoff between capacity and transport. Modeling and measurements of nanoporous gold electrodes has allowed us to determine design principles, including the fact that these materials can deplete salt from the electrolyte, increasing resistance. We have developed fabrication techniques to demonstrate architectures inspired by these principles that may overcome identified obstacles. A key concept is that electrodes should be as close together as possible; this is likely to involve an interpenetrating pore structure. However, this may prove extremely challenging to fabricate at the finest scales; a hierarchically porous structure can be a worthy compromise.

  2. Strong, Lightweight, Porous Materials

    NASA Technical Reports Server (NTRS)

    Leventis, Nicholas; Meador, Mary Ann B.; Johnston, James C.; Fabrizio, Eve F.; Ilhan, Ulvi

    2007-01-01

    A new class of strong, lightweight, porous materials has been invented as an outgrowth of an effort to develop reinforced silica aerogels. The new material, called X-Aerogel is less hygroscopic, but no less porous and of similar density to the corresponding unmodified aerogels. However, the property that sets X-Aerogels apart is their mechanical strength, which can be as much as two and a half orders of magnitude stronger that the unmodified aerogels. X-Aerogels are envisioned to be useful for making extremely lightweight, thermally insulating, structural components, but they may also have applications as electrical insulators, components of laminates, catalyst supports, templates for electrode materials, fuel-cell components, and filter membranes.

  3. Edible packaging materials.

    PubMed

    Janjarasskul, Theeranun; Krochta, John M

    2010-01-01

    Research groups and the food and pharmaceutical industries recognize edible packaging as a useful alternative or addition to conventional packaging to reduce waste and to create novel applications for improving product stability, quality, safety, variety, and convenience for consumers. Recent studies have explored the ability of biopolymer-based food packaging materials to carry and control-release active compounds. As diverse edible packaging materials derived from various by-products or waste from food industry are being developed, the dry thermoplastic process is advancing rapidly as a feasible commercial edible packaging manufacturing process. The employment of nanocomposite concepts to edible packaging materials promises to improve barrier and mechanical properties and facilitate effective incorporation of bioactive ingredients and other designed functions. In addition to the need for a more fundamental understanding to enable design to desired specifications, edible packaging has to overcome challenges such as regulatory requirements, consumer acceptance, and scaling-up research concepts to commercial applications.

  4. Hazardous materials dictionary

    SciTech Connect

    Coleman, R.J.

    1987-01-01

    Parallel growth of the chemical industry of emergency response capabilities in the public and private sectors has created a new need for improved communications. A new vocabulary of important terms is emerging in each of the industries that transport, store and handle hazardous materials. This dictionary, representing a compilation of words and phrases from many relevant sources, will help document and standardize the nomenclature of hazardous materials. The authors have screened the technical discourse of the chemical, transportation, petroleum and medical fields, both governmental and private, to determine the most current expressions and their uses. The lexicographic goal has been to identify key terms, ambiguous and multiple meaning words, acronyms, symbols and even slang referring to hazardous materials reactions, storing and handling procedures.

  5. [Materials for mouth protectors].

    PubMed

    Kloeg, E F; Collys, K

    2003-01-01

    Taking into account the number of teeth which are yearly irreversible traumatised during sport activities, the general use of mouthguards would contribute positively to the prevention of dental injuries. Custom-made mouthguards are more comfortable to wear and offer better retention and protection than stock and mouth-formed mouthguards. Different kinds of materials are available on the market for the construction of mouthguards. A polyethylene-polyvinylacetate copolymer (EVA) is the most suitable material. EVA allows the inclusion of hard or soft layers within the mouthguard. The thickness of a mouthguard is important for the reduction of applied forces to teeth: energy absorption capacity increases with material thickness. Increased thickness however, is associated with a reduction of comfort. Therefore, it is important that dentists take the patients' wishes and demands on both comfort and protection into consideration. A description of the clinical and technical method for the construction of a custom made mouthguard is given. PMID:12894661

  6. Modified Composite Materials Workshop

    NASA Technical Reports Server (NTRS)

    Dicus, D. L. (Compiler)

    1978-01-01

    The reduction or elimination of the hazard which results from accidental release of graphite fibers from composite materials was studied at a workshop. At the workshop, groups were organized to consider six topics: epoxy modifications, epoxy replacement, fiber modifications, fiber coatings and new fibers, hybrids, and fiber release testing. Because of the time required to develop a new material and acquire a design data base, most of the workers concluded that a modified composite material would require about four to five years of development and testing before it could be applied to aircraft structures. The hybrid working group considered that some hybrid composites which reduce the risk of accidental fiber release might be put into service over the near term. The fiber release testing working group recommended a coordinated effort to define a suitable laboratory test.

  7. Polymers from renewable materials.

    PubMed

    Rus, Anika Zafiah M

    2010-01-01

    With the world facing depletion of its oil reserves, attention is being focused on how the plastics industry will address shortages and price increases in its crucial raw materials. One renewable resource is that of vegetable oils and fats and about a dozen crop plants make up the main vegetable oil-seed market. The main constituents of these oils are saturated and unsaturated fatty acids that are unique to the plant in which they have been developed. Moreover, technological processes can produce more well-defined and pure oils, and the fatty acid contents in the vegetable oils can be altered with modern crop development techniques. This article describes recent advances in utilising such vegetable oils in sourcing new polymeric materials. It also gives the context for the development of polymers based on renewable materials in general.

  8. Radiation effects in materials

    NASA Astrophysics Data System (ADS)

    Dauphin, J.

    1994-01-01

    In contrast to electronic components, materials are, in general, quite resistant to the conditions encountered in space from the point of view of radiation effects. There exist however some groups of materials which can cause concern, particularly when they are used on the outside of spacecraft. These include fluorinated polymers, oxide glasses and paints. Normally only very sensitive properties like the thermo-optical ones may be significantly degraded in near earth space. The extremely used geostationary orbit is the most dangerous in this respect. Another characteristic of materials is that degration is a complex phenomenon, of which particulate radiation is not the only cause. Synergistic effects are the rule and the influence of the complete space environment including temperature, UV radiation, particles, contamination, etc. must be assessed. This strongly complicates the ground simulation experiments.

  9. Oxygen ion conducting materials

    DOEpatents

    Vaughey, John; Krumpelt, Michael; Wang, Xiaoping; Carter, J. David

    2005-07-12

    An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

  10. Oxygen ion conducting materials

    DOEpatents

    Carter, J. David; Wang, Xiaoping; Vaughey, John; Krumpelt, Michael

    2004-11-23

    An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

  11. Composite material radomes

    NASA Astrophysics Data System (ADS)

    Carbone, R.; Simon, J.-Y.

    1987-06-01

    The fabrication of radomes from composite materials, for naval and aeronautical applications including the Mirage II, F1, and Mirage 2000, is discussed. The diverse radioelectric and mechanical requirements of radomes are best met in the average-temperature regime by reinforced plastics, and in the elevated supersonic regime by ceramic materials. The structural criteria of radomes concerning aerodynamic, inertial, and vibrational loading, and the environmental criteria concerning temperature, sand and rain erosion, and lightning effects, are reviewed. Materials considered for radome fabrication include modified polyesters, epoxies, and thermostable resins, using glass, silica, and aramide tissues or threads as the reinforcements. The advantages and disadvantages of the various fabrication methods, and the fabrication of monolithic radomes by winding and by using preformed weaves, are also discussed.

  12. Porous material neutron detector

    DOEpatents

    Diawara, Yacouba; Kocsis, Menyhert

    2012-04-10

    A neutron detector employs a porous material layer including pores between nanoparticles. The composition of the nanoparticles is selected to cause emission of electrons upon detection of a neutron. The nanoparticles have a maximum dimension that is in the range from 0.1 micron to 1 millimeter, and can be sintered with pores thereamongst. A passing radiation generates electrons at one or more nanoparticles, some of which are scattered into a pore and directed toward a direction opposite to the applied electrical field. These electrons travel through the pore and collide with additional nanoparticles, which generate more electrons. The electrons are amplified in a cascade reaction that occurs along the pores behind the initial detection point. An electron amplification device may be placed behind the porous material layer to further amplify the electrons exiting the porous material layer.

  13. Materials property measurements

    SciTech Connect

    Boyd, D.M.; Green, E.R.; Doctor, S.R.; Good, M.S.

    1990-04-19

    An in-depth review of the measurement techniques that could be used in materials characterization is presented. The measurement techniques to non-destructively determine the in-service or time-related aging of materials considered include ultrasonic velocity and attenuation, eddy current conductivity, neutron scattering and absorption, conventional and tomographic imaging for ultrasonic and radiation imaging, x-ray scattering, thermal impedance, and magnetic hysteresis. The three sections of the report include a review of failure mechanisms in steel and a discussion of nondestructive evaluation techniques and fracture mechanics, a description of a chart on Measurement Techniques versus Material Properties, and recommendations on the techniques and tests to be performed for the experimental investigations and analysis task of the project. 49 refs., 7 figs.

  14. Oxygen ion conducting materials

    DOEpatents

    Vaughey, John; Krumpelt, Michael; Wang, Xiaoping; Carter, J. David

    2003-01-01

    An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

  15. Stirling material technology

    NASA Technical Reports Server (NTRS)

    Titran, R. H.; Stephens, J. R.; Scheuermann, C. M.

    1984-01-01

    The Stirling engine is an external combustion engine that offers the advantage of high fuel economy, low emissions, low noise, and low vibrations compared to current internal combustion automotive engines. The most critical component from a materials viewpoint is the heater head consisting of the cylinders, heating tubes, and regenerator housing. Materials requirements for the heater head include compatibility with hydrogen, resistance to hydrogen permeation, high temperature oxidation/corrosion resistance, and high temperature creep-rupture and fatigue properties. A materials research and technology program identified the wrought alloys CG-27 and 12RN72 and the cast alloys XF-818, NASAUT 4G-A1, and NASACC-1 as candidate replacements for the cobalt containing alloys used in current prototype engines. It is concluded that manufacture of the engine is feasible from low cost iron-base alloys rather than the cobalt alloys used in prototype engines. Results of research that lead to this conclusion are presented.

  16. Materials research. [research concerning materials for aerospace applications

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The research is reported concerned with materials for aerospace applications. Areas reported include: electrical properties of glasses, oxides and metals; structural and high temperature properties of crystalline and amorphous materials; and physical properties, and microstructure of materials.

  17. Correlation monitor materials

    SciTech Connect

    Corwin, W.R.

    1995-10-01

    This task has been established with the explicit purpose of ensuring the continued availability of the pedigreed and extremely well-characterized material now required for inclusion in all additional and future surveillance capsules in commercial light-water reactors. During this reporting period, concrete was poured and pallets storage racks were installed to provide adequate room for the storage of the correlation monitor material being transferred from its location at the Y-12 Plant to its archival storage location at ORNL. The racks came from surplus material storage at ORNL and hence were obtained at no cost to the HSSI Program. Inquiries into cost-effective means of sheltering the blocks of correlation monitor materials from further weather-related deteriorization were initiated. The most likely approach would be to procure a turn-key sheet metal building installed over the storage racks by an outside contractor to minimize costs. Most of the material has now been transferred from Y-12 to the ORNL storage area. It has been repositioned on new storage pallets and placed into the storage racks, An update of the detailed material inventory was initiated to ascertain the revised location of all blocks. Pieces of HSST plate O3 were distributed to participants in the ASTM cross-comparison exercise on subsize specimen testing technology. The use of the HSST O3 will provide for data from the many varieties of tests to be performed to be compared with the standardized data previously developed. The testing techniques will focus on ways to measure transition temperature and fracture toughness.

  18. MATERIAL CONTROL ACCOUNTING INMM

    SciTech Connect

    Hasty, T.

    2009-06-14

    Since 1996, the Mining and Chemical Combine (MCC - formerly known as K-26), and the United States Department of Energy (DOE) have been cooperating under the cooperative Nuclear Material Protection, Control and Accounting (MPC&A) Program between the Russian Federation and the U.S. Governments. Since MCC continues to operate a reactor for steam and electricity production for the site and city of Zheleznogorsk which results in production of the weapons grade plutonium, one of the goals of the MPC&A program is to support implementation of an expanded comprehensive nuclear material control and accounting (MC&A) program. To date MCC has completed upgrades identified in the initial gap analysis and documented in the site MC&A Plan and is implementing additional upgrades identified during an update to the gap analysis. The scope of these upgrades includes implementation of MCC organization structure relating to MC&A, establishing material balance area structure for special nuclear materials (SNM) storage and bulk processing areas, and material control functions including SNM portal monitors at target locations. Material accounting function upgrades include enhancements in the conduct of physical inventories, limit of error inventory difference procedure enhancements, implementation of basic computerized accounting system for four SNM storage areas, implementation of measurement equipment for improved accountability reporting, and both new and revised site-level MC&A procedures. This paper will discuss the implementation of MC&A upgrades at MCC based on the requirements established in the comprehensive MC&A plan developed by the Mining and Chemical Combine as part of the MPC&A Program.

  19. Aerogel/polymer composite materials

    NASA Technical Reports Server (NTRS)

    Williams, Martha K. (Inventor); Smith, Trent M. (Inventor); Fesmire, James E. (Inventor); Roberson, Luke B. (Inventor); Clayton, LaNetra M. (Inventor)

    2010-01-01

    The invention provides new composite materials containing aerogels blended with thermoplastic polymer materials at a weight ratio of aerogel to thermoplastic polymer of less than 20:100. The composite materials have improved thermal insulation ability. The composite materials also have better flexibility and less brittleness at low temperatures than the parent thermoplastic polymer materials.

  20. Sandia Material Model Driver

    2005-09-28

    The Sandia Material Model Driver (MMD) software package allows users to run material models from a variety of different Finite Element Model (FEM) codes in a standalone fashion, independent of the host codes. The MMD software is designed to be run on a variety of different operating system platforms as a console application. Initial development efforts have resulted in a package that has been shown to be fast, convenient, and easy to use, with substantialmore » growth potential.« less

  1. Refractory composites structural materials

    NASA Astrophysics Data System (ADS)

    Sanzero, G. V.

    1990-10-01

    This paper presents the latest available data for the NASP Refractory Composites Materials and Structures Augmentation Program. The program's main goal is to provide the necessary information for a positive phase II to phase III plan for the X-30 to be built. After a brief overview of the program, the state-of-the-art fabrication of carbon/carbon subelements is presented. Material data packages for screening data, characterization data, damage and durability tolerance and actively-cooled airframe and engine program development are also presented.

  2. Fabrication of cellular materials

    NASA Astrophysics Data System (ADS)

    Prud'homme, Robert K.; Aksay, Ilhan A.; Garg, Rajeev

    1996-02-01

    Nature uses cellular materials in applications requiring strength while, simultaneously, minimizing raw materials requirements. Minimizing raw materials is efficient both in terms of the energy expended by the organism to synthesize the structure and in terms of the strength- to-weight ratio of the structure. Wood is the most obvious example of cellular bio-materials, and it is the focus of other presentations in this symposium. The lightweight bone structure of birds is another excellent example where weight is a key criterion. The anchoring foot of the common muscle [Mytilus edulis] whereby it attaches itself to objects is a further example of a biological system that uses a foam to fill space and yet conserve on raw materials. In the case of the muscle the foam is water filled and the foot structure distributes stress over a larger area so that the strength of the byssal thread from which it is suspended is matched to the strength of interfacial attachment of the foot to a substrate. In these examples the synthesis and fabrication of the cellular material is directed by intercellular, genetically coded, biochemical reactions. The resulting cell sizes are microns in scale. Cellular materials at the next larger scale are created by organisms at the next higher level of integration. For example an African tree frog lays her eggs in a gas/fluid foam sack she builds on a branch overhanging a pond. The outside of the foam sack hardens in the sun and prevents water evaporation. The foam structure minimizes the amount of fluid that needs to be incorporated into the sack and minimizes its weight. However, as far as the developing eggs are concerned, they are in an aqueous medium, i.e. the continuous fluid phase of the foam. After precisely six days the eggs hatch, and the solidified outer wall re-liquefies and dumps the emerging tadpoles into the pond below. The bee honeycomb is an example of a cellular material with exquisite periodicity at millimeter length scales. The

  3. LDEF Materials/Contamination

    NASA Technical Reports Server (NTRS)

    Pippin, Gary

    1997-01-01

    This pictorial presentation reviews the post-flight analysis results from two type of hardware (tray clamp bolt heads and uhcre flight experiment tray walls) from the Long Duration Exposure Facility (LDEF). It will also discuss flight hardware for one upcoming (Effects of the Space Environment on Materials (ESEM) flight experiment), and two current flight experiments evaluating the performance of materials in space (Passive Optical Sample Assembly (POSA) 1&2 flight experiments. These flight experiments also are concerned with contamination effects which will also be discussed.

  4. Materials separation by dielectrophoresis

    NASA Technical Reports Server (NTRS)

    Sagar, A. D.; Rose, R. M.

    1988-01-01

    The feasibility of vacuum dielectrophoresis as a method for particulate materials separation in a microgravity environment was investigated. Particle separations were performed in a specially constructed miniature drop-tower with a residence time of about 0.3 sec. Particle motion in such a system is independent of size and based only on density and dielectric constant, for a given electric field. The observed separations and deflections exceeded the theoretical predictions, probably due to multiparticle effects. In any case, this approach should work well in microgravity for many classes of materials, with relatively simple apparatus and low weight and power requirements.

  5. Organic nonlinear optical materials

    NASA Technical Reports Server (NTRS)

    Umegaki, S.

    1987-01-01

    Recently, it became clear that organic compounds with delocalized pi electrons show a great nonlinear optical response. Especially, secondary nonlinear optical constants of more than 2 digits were often seen in the molecular level compared to the existing inorganic crystals such as LiNbO3. The crystallization was continuously tried. Organic nonlinear optical crystals have a new future as materials for use in the applied physics such as photomodulation, optical frequency transformation, opto-bistabilization, and phase conjugation optics. Organic nonlinear optical materials, e.g., urea, O2NC6H4NH2, I, II, are reviewed with 50 references.

  6. Corrosion of Ceramic Materials

    NASA Technical Reports Server (NTRS)

    Opila, Elizabeth J.; Jacobson, Nathan S.

    1999-01-01

    Non-oxide ceramics are promising materials for a range of high temperature applications. Selected current and future applications are listed. In all such applications, the ceramics are exposed to high temperature gases. Therefore it is critical to understand the response of these materials to their environment. The variables to be considered here include both the type of ceramic and the environment to which it is exposed. Non-oxide ceramics include borides, nitrides, and carbides. Most high temperature corrosion environments contain oxygen and hence the emphasis of this chapter will be on oxidation processes.

  7. Lasers in materials processing

    SciTech Connect

    Davis, J.I.; Rockower, E.B.

    1981-01-01

    A status report on the uranium Laser Isotope Separation (LIS) Program at the Lawrence Livermore National Laboratory is presented. Prior to this status report, process economic analysis is presented so as to understand how the unique properties of laser photons can be best utilized in the production of materials and components despite the high cost of laser energy. The characteristics of potential applications that are necessary for success are identified, and those factors that have up to now frustrated attempts to find commercially viable laser induced chemical and physical process for the production of new or existing materials are pointed out.

  8. Optical limiting materials

    DOEpatents

    McBranch, Duncan W.; Mattes, Benjamin R.; Koskelo, Aaron C.; Heeger, Alan J.; Robinson, Jeanne M.; Smilowitz, Laura B.; Klimov, Victor I.; Cha, Myoungsik; Sariciftci, N. Serdar; Hummelen, Jan C.

    1998-01-01

    Optical limiting materials. Methanofullerenes, fulleroids and/or other fullerenes chemically altered for enhanced solubility, in liquid solution, and in solid blends with transparent glass (SiO.sub.2) gels or polymers, or semiconducting (conjugated) polymers, are shown to be useful as optical limiters (optical surge protectors). The nonlinear absorption is tunable such that the energy transmitted through such blends saturates at high input energy per pulse over a wide range of wavelengths from 400-1100 nm by selecting the host material for its absorption wavelength and ability to transfer the absorbed energy into the optical limiting composition dissolved therein. This phenomenon should be generalizable to other compositions than substituted fullerenes.

  9. Ultrasonic Processing of Materials

    SciTech Connect

    Meek, Thomas T.; Han, Qingyou; Jian, Xiaogang; Xu, Hanbing

    2005-06-30

    The purpose of this project was to determine the impact of a new breakthrough technology, ultrasonic processing, on various industries, including steel, aluminum, metal casting, and forging. The specific goals of the project were to evaluate core principles and establish quantitative bases for the ultrasonc processing of materials, and to demonstrate key applications in the areas of grain refinement of alloys during solidification and degassing of alloy melts. This study focussed on two classes of materials - aluminum alloys and steels - and demonstrated the application of ultrasonic processing during ingot casting.

  10. Hazardous-Materials Robot

    NASA Technical Reports Server (NTRS)

    Stone, Henry W.; Edmonds, Gary O.

    1995-01-01

    Remotely controlled mobile robot used to locate, characterize, identify, and eventually mitigate incidents involving hazardous-materials spills/releases. Possesses number of innovative features, allowing it to perform mission-critical functions such as opening and unlocking doors and sensing for hazardous materials. Provides safe means for locating and identifying spills and eliminates risks of injury associated with use of manned entry teams. Current version of vehicle, called HAZBOT III, also features unique mechanical and electrical design enabling vehicle to operate safely within combustible atmosphere.

  11. Losses in Ferroelectric Materials

    PubMed Central

    Liu, Gang; Zhang, Shujun; Jiang, Wenhua; Cao, Wenwu

    2015-01-01

    Ferroelectric materials are the best dielectric and piezoelectric materials known today. Since the discovery of barium titanate in the 1940s, lead zirconate titanate ceramics in the 1950s and relaxor-PT single crystals (such as lead magnesium niobate-lead titanate and lead zinc niobate-lead titanate) in the 1980s and 1990s, perovskite ferroelectric materials have been the dominating piezoelectric materials for electromechanical devices, and are widely used in sensors, actuators and ultrasonic transducers. Energy losses (or energy dissipation) in ferroelectrics are one of the most critical issues for high power devices, such as therapeutic ultrasonic transducers, large displacement actuators, SONAR projectors, and high frequency medical imaging transducers. The losses of ferroelectric materials have three distinct types, i.e., elastic, piezoelectric and dielectric losses. People have been investigating the mechanisms of these losses and are trying hard to control and minimize them so as to reduce performance degradation in electromechanical devices. There are impressive progresses made in the past several decades on this topic, but some confusions still exist. Therefore, a systematic review to define related concepts and clear up confusions is urgently in need. With this objective in mind, we provide here a comprehensive review on the energy losses in ferroelectrics, including related mechanisms, characterization techniques and collections of published data on many ferroelectric materials to provide a useful resource for interested scientists and engineers to design electromechanical devices and to gain a global perspective on the complex physical phenomena involved. More importantly, based on the analysis of available information, we proposed a general theoretical model to describe the inherent relationships among elastic, dielectric, piezoelectric and mechanical losses. For multi-domain ferroelectric single crystals and ceramics, intrinsic and extrinsic energy

  12. Editorial: biodegradable materials.

    PubMed

    Schaschke, Carl; Audic, Jean-Luc

    2014-11-21

    This Special Issue "Biodegradable Materials" features research and review papers concerning recent advances on the development, synthesis, testing and characterisation of biomaterials. These biomaterials, derived from natural and renewable sources, offer a potential alternative to existing non-biodegradable materials with application to the food and biomedical industries amongst many others. In this Special Issue, the work is expanded to include the combined use of fillers that can enhance the properties of biomaterials prepared as films. The future application of these biomaterials could have an impact not only at the economic level, but also for the improvement of the environment.

  13. Thermal energy storage material

    DOEpatents

    Leifer, Leslie

    1976-01-01

    A thermal energy storage material which is stable at atmospheric temperature and pressure and has a melting point higher than 32.degree.F. is prepared by dissolving a specific class of clathrate forming compounds, such as tetra n-propyl or tetra n-butyl ammonium fluoride, in water to form a substantially solid clathrate. The resultant thermal energy storage material is capable of absorbing heat from or releasing heat to a given region as it transforms between solid and liquid states in response to temperature changes in the region above and below its melting point.

  14. Electron Beam Materials Irradiators

    NASA Astrophysics Data System (ADS)

    Cleland, Marshall R.

    2012-06-01

    Radiation processing is a well established method for enhancing the properties of materials and commercial products by treating them with ionizing energy in the form of high-energy electrons, X-rays, and gamma rays. Beneficial effects include polymerizing, cross-linking, grafting and degrading plastics, sterilizing single-use medical devices, disinfecting and disinfesting fresh foods, purifying drinking water, treating wastewater and other toxic waste materials that harm the environment, and many other applications that are still being evaluated. Industrial electron accelerators of several types have been developed and are being used for these applications. More than 1800 electron accelerators are presently installed in facilities worldwide for these purposes.

  15. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1979-01-01

    A multifaceted program is described in which aeronautical, mechanical, and materials engineers interact to develop composite aircraft structures. Topics covered include: (1) the design of an advanced composite elevator and a proposed spar and rib assembly; (2) optimizing fiber orientation in the vicinity of heavily loaded joints; (3) failure mechanisms and delamination; (4) the construction of an ultralight sailplane; (5) computer-aided design; finite element analysis programs, preprocessor development, and array preprocessor for SPAR; (6) advanced analysis methods for composite structures; (7) ultrasonic nondestructive testing; (8) physical properties of epoxy resins and composites; (9) fatigue in composite materials, and (10) transverse thermal expansion of carbon/epoxy composites.

  16. Container for radioactive materials

    DOEpatents

    Fields, S.R.

    1984-05-30

    A container is claimed for housing a plurality of canister assemblies containing radioactive material. The several canister assemblies are stacked in a longitudinally spaced relation within a carrier to form a payload concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path. 7 figures.

  17. Materials for geothermal production

    SciTech Connect

    Kukacka, L.E.

    1992-01-01

    Advances in the development of new materials continue to be made in the geothermal materials project. Many successes have already been accrued and the results used commercially. In FY 1991, work was focused on reducing well drilling, fluid transport and energy conversion costs. Specific activities performed included lightweight CO{sub 2}-resistant well cements, thermally conductive and scale resistant protective liner systems, chemical systems for lost circulation control, corrosion mitigation in process components at The Geysers, and elastomer-metal bonding systems. Efforts to transfer the technologies developed in these efforts to other energy-related sectors of the economy continued and considerable success was achieved.

  18. Gravitation in material media

    NASA Astrophysics Data System (ADS)

    Ridgely, Charles T.

    2011-03-01

    When two gravitating bodies reside in a material medium, Newton's law of universal gravitation must be modified to account for the presence of the medium. A modified expression of Newton's law is known in the literature, but lacks a clear connection with existing gravitational theory. Newton's law in the presence of a homogeneous material medium is herein derived on the basis of classical, Newtonian gravitational theory and by a general relativistic use of Archimedes' principle. It is envisioned that the techniques presented herein will be most useful to graduate students and those undergraduate students having prior experience with vector analysis and potential theory.

  19. Materials informatics: a journey towards material design and synthesis.

    PubMed

    Takahashi, Keisuke; Tanaka, Yuzuru

    2016-06-28

    Materials informatics has been gaining popularity with the rapid development of computational materials science. However, collaborations between information science and materials science have not yet reached the success. There are several issues which need to be overcome in order to establish the field of materials informatics. Construction of material big data, implementation of machine learning, and platform design for materials discovery are discussed with potential solutions. PMID:27292550

  20. Materials informatics: a journey towards material design and synthesis.

    PubMed

    Takahashi, Keisuke; Tanaka, Yuzuru

    2016-06-28

    Materials informatics has been gaining popularity with the rapid development of computational materials science. However, collaborations between information science and materials science have not yet reached the success. There are several issues which need to be overcome in order to establish the field of materials informatics. Construction of material big data, implementation of machine learning, and platform design for materials discovery are discussed with potential solutions.