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Sample records for conference hall kyoto

  1. 66. INTERIOR, FIRST FLOOR, WING 1100 EAST, AUDITORIUM (CONFERENCE HALL), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    66. INTERIOR, FIRST FLOOR, WING 1100 EAST, AUDITORIUM (CONFERENCE HALL), DETAIL OF BRONZE GRILL IN BLIND GALLERY - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  2. H2S2014 in Kyoto: the 3rd International Conference on H2S in Biology and Medicine.

    PubMed

    Kimura, Hideo

    2015-04-30

    About 20 years ago, a pungent gas was found to be the physiological mediator of cognitive function and vascular tone. Since then, studies on hydrogen sulfide (H2S) have uncovered its numerous physiological roles such as protecting various tissues/organs from ischemia and regulating inflammation, cell growth, oxygen sensing, and senescence. These effects of H2S were extensively studied, and some of the corresponding mechanisms were also studied in detail. Previous studies on the synergistic interaction between H2S and nitric oxide (NO) have led to the discovery of several potential signaling molecules. Polysulfides are considerably potent and are one of the most active forms of H2S. H2S has a significant therapeutic potential, which is evident from the large number of novel H2S-donating compounds and substances developed for manipulating endogenous levels of H2S. The Third International Conference on H2S was held in Kyoto in June 2014. One hundred and sixty participants from 21 countries convened in Kyoto to report new advances, discuss conflicting findings, and make plans for future research. This article summarizes each oral presentation presented at the conference.

  3. Education for Peace: A Conference Report from Kyoto. Peace Education Reports No. 6.

    ERIC Educational Resources Information Center

    Bjerstedt, Ake, Ed.

    Conference sessions of the Peace Education Commission (PEC), a transnational network of people interested in peace education and research related to peace education, are reported in this document. Following an introductory overview of the conference as a whole, the report is divided into four parts. The first part contains three area studies; that…

  4. Identifying gaps in the locoregional management of early breast cancer: highlights from the Kyoto Consensus Conference.

    PubMed

    Toi, Masakazu; Winer, Eric P; Inamoto, Takashi; Benson, John R; Forbes, John F; Mitsumori, Michihide; Robertson, John F R; Sasano, Hironobu; von Minckwitz, Gunter; Yamauchi, Akira; Klimberg, V Suzanne

    2011-10-01

    A consensus conference was held to investigate issues related to the local management of early breast cancer. Here, we highlight the major topics discussed at the conference and propose ideas for future studies. Regarding axillary management, we examined three major issues. First, we discussed whether the use of axillary reverse mapping could clarify the lymphatic system of breast and whether the ipsilateral arm might help avoid lymphedema. Second, the use of an indocyanine green fluorescent navigation system was discussed for intraoperative lymphatic mapping. These new issues should be examined further in practice. Finally, some agreement was reached on the importance of "four-node diagnosis" to aid in the diagnostic accuracy of sentinel nodes. Regarding breast treatment, there was general agreement that the clinical value of surgical margins in predicting local failure was dependent on the tumor's intrinsic biology and subtypes. For patients treated with preoperative chemotherapy, less extensive excision may be feasible in those who respond to systemic therapy in an acceptable manner. Most trials of preoperative chemotherapy lack outcome data on local recurrence. Therefore, there is a need for such data for overview analysis. We also agreed that radiation after mastectomy may be beneficial in node-positive cases where more than four nodes are involved. Throughout the discussions for both invasive and noninvasive disease, the investigation of nomograms was justified for major issues in the decision-making process, such as the presence or absence of microinvasion and the involvement of nonsentinel nodes in sentinel node-positive patients.

  5. Tunnelling anomalous and planar Hall effects (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Matos-Abiague, Alex; Scharf, Benedikt; Han, Jong E.; Hankiewicz, Ewelina M.; Zutic, Igor

    2016-10-01

    We theoretically show how the interplay between spin-orbit coupling (SOC) and magnetism can result in a finite tunneling Hall conductance, transverse to the applied bias. For two-dimensional tunnel junctions with a ferromagnetic lead and magnetization perpendicular to the current flow, the detected anomalous Hall voltage can be used to extract information not only about the spin polarization but also about the strength of the interfacial SOC. In contrast, a tunneling current across a ferromagnetic barrier on the surface of a three-dimensional topological insulator (TI) can induce a planar Hall response even when the magnetization is oriented along the current flow[1]. The tunneling nature of the states contributing to the planar Hall conductance can be switched from the ordinary to the Klein regimes by the electrostatic control of the barrier strength. This allows for an enhancement of the transverse response and a giant Hall angle, with the tunneling planar Hall conductance exceeding the longitudinal component. Despite the simplicity of a single ferromagnetic region, the TI/ferromagnet system exhibits a variety of functionalities. In addition to a spin-valve operation for magnetic sensing and storing information, positive, negative, and negative differential conductances can be tuned by properly adjusting the barrier potential and/or varying the magnetization direction. Such different resistive behaviors in the same system are attractive for potential applications in reconfigurable spintronic devices. [1] B. Scharf, A. Matos-Abiague, J. E. Han, E. M. Hankiewicz, and I. Zutic, arXiv:1601.01009 (2016).

  6. Spin Hall effects in metallic multilayers (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Woltersdorf, Georg; Wei, Dahai H.; Obstbaum, Martin; Back, Christian H.; Decker, Martin

    2016-10-01

    We study the direct as well as the inverse SHE. In the case of the direct SHE a dc charge current is applied in the plane of a ferromagnet/normal metal layer stack and the SHE creates a spin polarization at the surface of the normal metal leading to the injection of a spin current into the ferromagnet. This spin current is absorbed in the ferromagnet and causes a spin transfer torque. Using time and spatially resolved Kerr microscopy we measure the transferred spin momentum and compute the spin Hall angle. In a second set of experiments using identical samples pure spin currents are injected by the spin pumping effect from the ferromagnet into the normal metal. The spin current injected by spin pumping has a large ac component transverse to the static magnetization direction and a very small dc component parallel to the magnetization direction. The inverse SHE converts these spin current into charge current. The corresponding inverse SHE voltages induced by spin pumping at ferromagnetic resonance are measured in permalloy/platinum and permalloy/gold multilayers in various excitation geometries and as a function of frequency in order to separate the contributions of anisotropic magnetoresistance and SHE. In addition, we present experimental evidence for the ac component of inverse SHE voltages generated by spin pumping.

  7. Spin polarized tunneling study on spin hall metals and topological insulators (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Liu, Luqiao

    2016-10-01

    Spin orbit interactions give rise to interesting physics phenomena in solid state materials such as the spin Hall effect (SHE) and topological insulator surface states. Those effects have been extensively studied using various electrical detection methods. However, to date most experiments focus only on characterizing electrons near the Fermi surface, while spin-orbit interaction is expected to be energy dependent. Here we developed a tunneling spectroscopy technique to measure spin Hall materials and topological insulators under finite bias voltages. By electrically injecting spin polarized electrons into spin Hall metals or topological insulators using tunnel junctions and measuring the induced transverse voltage, we are able to study SHE in typical 5d transition metals and the spin momentum locking in topological insulators. For spin Hall effect metals, the magnitude of the spin Hall angle has been a highly controversial topic in previous studies. Results obtained from various techniques can differ by more than an order of magnitude. Our results from this transport measurement turned out to be consistent with the values obtained from spin Hall torque measurements, which can help to address the long debating issue. Besides the magnitude, the voltage dependent spectra from our experiment also provide useful information in distinguishing between different potential mechanisms. Finally, because of the impedance matching capability of tunnel junctions, the spin polarized tunneling technique can also be used as a powerful tool to measure resistive materials such as the topological insulators. Orders of magnitude improvement in the effective spin Hall angle was demonstrated through our measurement

  8. Report from the 29th World Congress of Endourology and SWL (November 30-December 3, 2011 - Kyoto, Japan).

    PubMed

    Rabasseda, X

    2012-02-01

    Kyoto is a city of surprises: from the most beautiful castles and temples known far and wide across the world, to the humblest temples, as beautiful as those appearing in all tourist guides, just hidden away in small lanes among busy traffic of bicycles and pedestrians shopping in markets or attending to their daily business. Add the innumerable tourists busily exploring the city's attractions, although this was not the reason for visiting Kyoto, which was the site of this year's World Congress of Endourology and SWL. Nevertheless, maybe as a compensation, the meeting was held in Kokusaikaikan, literally the International Conference Centre, which is a modern facility in the city outskirts, actually adjoining the Takaragaike park, with a beautiful lake and the mountains, brightly led by the trees' red leaves, just visible through the main hall windows.

  9. Climate change: The impact of the third conference of the parties at Kyoto on the U.S. Portland cement industry

    SciTech Connect

    Cahn, D.; Nisbet, M.; O`Hare, A.

    1998-12-31

    The paper provides, as background, a brief review of the structure of the US cement industry. It outlines the growth trends of the industry over the last 20 years. It describes the sources and significance of cement imports in the US market, and the importance of exports to Canadian cement producers. The sources of CO{sub 2}, the primary greenhouse gas emitted in the cement manufacturing process, are explained and the impact of improved energy efficiency and fuel switching on CO{sub 2} emissions per ton of product are discussed. The aspects of the Kyoto Protocol relevant to the US cement industry are analyzed as are the types of impacts they can be expected to have on: cement trade, domestic cement production, long term growth of the US cement industry, and US cement industry CO{sub 2} emissions. The paper projects the US cement industry CO{sub 2} emissions to 2010, taking into account anticipated improvements in energy efficiency. It discusses manufacturing process and changes that could be made to reduce CO{sub 2} emissions. The paper also covers the types of product modifications that might be made to reduce the embodied CO{sub 2} content. Where possible the potential reductions in CO{sub 2} emissions from process and product changes are quantified.

  10. Extrinsic spin- and orbital-Hall effect in cyclic group symmetric metamaterial (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Lee, Yeon Ui; Ozerov, Igor; Bedu, Frederic; Fages, Frederic; Wu, Jeong Weon

    2016-09-01

    We designed and fabricated cyclic group symmetric metamaterials (CGSMs), anisotropic media showing an extrinsic optical orbital Hall effect. An exchange of angular momentum between spin and orbital angular momenta takes place in an optical beam propagating through anisotropic media such as plasmonic nanoantennas of concentric ring and tapered arc (TA) shape. In case of TA antenna an cross-polarized circular polarization scattered beam exhibits an extrinsic orbital Hall effect. The CGSMs possess n-fold rotation symmetry and they are composed of plasmonic TA antennas. In case of circular polarization, the TA antennas effectively scatter incident light depending on the beam helicity. Both amplitude and phase gradients take place along the azimuthal direction for cross-polarized beams. We used electron beam lithography to fabricate 30nm thick gold metamaterials patterned on borosilicate glass substrates. Six types of CGSMs with the symmetry order n from 1 to 6 were fabricated and measured. Each CSGM is composed of multiple TA antennas with the width varying from 45nm to 150nm organized in 8*n azimuthal segments of concentric rings repeated with 600nm radial spacing. Measurements of orbital Hall transverse shifts of circularly polarized beams of right/left helicity were carried out at a wavelength of 1300nm. Because TA antennas are arranged in a metamaterial with a cyclic group n-fold rotation symmetry, the extrinsic orbital Hall transverse shifts from CGSM exhibit a geometrical pattern with the same symmetry. However, CGSMs with odd and even symmetry orders show a strongly contrasting difference in the character of transverse shifts. The observed geometrical patterns agree well with those obtained from FDTD theoretical simulation.

  11. Spin Hall effect in 5d Au: W transition metal alloys (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Laczkowski, Piotr; Rojas-Sánchez, Juan Carlos; Savero-Torres, Williams; Reyren, Nicolas; Deranlot, Cyrile; George, Jean-Marie; Jaffrès, Henri; Fu, Yu; Marty, Alain; Warin, Patrick; Attané, Jean-Philippe; Vila, Laurent; Fert, Albert

    2016-10-01

    The spin Hall effect (SHE) [1] allows for a reciprocal conversion between charge and spin currents using the spin orbit coupling which can be at the core of several promising spintronics devices. The spin orbit interaction is used to produce a transverse flow of spin or charge in response to a longitudinal excitation, these are the direct or inverse SHE. The spin Hall angle (SHA), the ratio of longitudinal and transverse electronic conductivities, is the characterising parameter of this conversion. So far, large SHA have been reported in transition metals like Pt, Pd, W, Beta-Ta and in a few alloys with large spin orbit coupling impurities: CuIr, CuBi or CuPb [2]. In this presentation we will report on our study of the SHA in Au based alloys [3] which exhibits a non-monotonic relation with the impurity concentration. In the regime of diluted alloys this behaviour suggests the dominent side-jump contribution to the spin Hall resistivity, thus allowing precise tuning of the SHA as a function of impurities concentration. We will present our analyses results by using the Lateral Spin Valves, with newly introduced spin-absorption model adapted to the case of the strong spin-orbit interactions and by using complementary Ferromagnetic-Resonance/Spin-Pumping technique thus demonstrating very large SHA of the order of 15 % or even larger. [1] J.E. Hirsch, PRL 83, 1834 (1999). [2] Y. Niimi et al., PRL 106, 126601 (2011), PRL 109, 156602 (2012), PRB 89, 054401 (2014). [3] P. Laczkowski et al., APL 104, 142403 (2014) [4] E. Saitoh, et al., APL 88, 182509 (2006).

  12. PREFACE: Beyond Kyoto - the necessary road

    NASA Astrophysics Data System (ADS)

    Margrethe Basse, Ellen

    2009-03-01

    The Beyond Kyoto conference in Aarhus March 2009 was organised in collaboration with other knowledge institutions, businesses and authorities. It brought together leading scientists, policy-makers, authorities, intergovernmental organisations, NGO's, business stakeholders and business organisations. The conference was a joint interdisciplinary project involving many academic areas and disciplines. These conference proceedings are organised in central and recurring themes that cut across many debates on climate change, the climatic challenges as well as the solutions. In the front there is a short presentation of the conference concept. Part I of the proceedings focuses on issues related to the society - covering climate policy, law, market based instruments, financial structure, behaviour and consumption, public participation, media communication and response from indigenous peoples etc. Part II of the proceedings concerns the scientific knowledge base on climate related issues - covering climate change processes per se, the potential impacts of projected climate change on biodiversity and adaptation possibilities, the interplay between climate, agriculture and biodiversity, emissions, agricultural systems, increasing pressure on the functioning of agriculture and natural areas, vulnerability to extreme weather events and risks in respect to sea-level rise etc. The conference proceedings committee consists of four professors from Aarhus University: Jens-Christian Svenning, Jørgen E Olesen, Mads Forchhammer and Ellen Margrethe Basse. Aarhus University's Climate Secretariat has had the overall responsibility for coordinating the many presentations, as well as the practical side of arranging the conference and supporting the publication of papers. As Head of the Climate Secretariat and Chair of Aarhus University's Climate Panel, I would like to thank everyone for their contribution. This applies both to the scientific and the practical efforts. Special thanks to

  13. The Global Systems Analysis and Simulation (GLOSAS) Project, and the Global Lecture Hall (GLH) Operating at the Orlando ICEM Conference.

    ERIC Educational Resources Information Center

    Bell, John

    1993-01-01

    Introduces two articles which describe an interactive video conference between North and South America, the Caribbean, Europe, and Scandinavia as part of the International Council for Educational Media (ICEM) 1992 conference. (EAM)

  14. Gate control of spin polarization in a quantum Hall regime toward reconfigurable network of helical channels (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Rokhinson, Leonid; Kazakov, Aleksandr; Simion, George; Lyanda-Geller, Yuli; Kolkovsky, Valery; Karczewski, Grzegorz; Adamus, Zbigniew; Wojtowicz, Tomasz

    2016-10-01

    Several experiments in nanowires detected signatures of Majorana fermions, building block for topologicaly protected quantum computer. Now the focus of research is shifting toward systems where non-Abelian statistics of excitations can be demonstrated. To achieve this goal we are developing a new dilute magnetic semiconductor-based platform where non-Abelian excitations can be created and manipulated in a two-dimensional plane, with support for Majorana and higher order non-Abelian excitations. Here we report development of heterostructures where spin polarization of a two-dimensional electron gas in a quantum Hall regime can be controlled locally by electrostatic gating. This is demonstrated via voltage induced shift of quantum Hall ferromagnetic transition in the CdTe quantum wells with engineered placement of paramagnetic Mn impurities. The structures can be used to form helical domain walls in integer quantum Hall regime which, coupled to an s-wave superconductor, are expected to support Majorana zero modes. These heterostructures can be used as a testbed to study gate-reconfigurable domain walls networks.

  15. Spin-pumping and spin-Hall magnetoresistance (SMR) at transition metal interfaces: case of (Co/Pt) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Jaffres, Henri; George, Jean-Marie; Laczowski, Piotr; Reyren, Nicolas; Vila, Laurent

    2016-10-01

    Spintronic phenomena are made possible via the diffusion of spin-currents or the generation of spin-accumulation. Spinorbitronics uses the electronic spin-orbit coupling (SOC) and emerges as a new route to create spin-currents in the transverse direction of the charge flow. This is made possible via the intrinsic spin Hall conduction (SHE) of heavy metals or extrinsic spin-Hall effect of metallic alloys. SHE borrows its concept from the anomalous Hall effect (AHE) where the relativistic spin-orbit coupling (SOC) promotes an asymmetric deflection of the spin-current. SHE is now at the base of magnetization commutation and domain wall moving via spin-orbit torque (SOT) and spin-transfer torque operations in the FMR regime. However, the exact anatomy of SOT at spin-orbit active interfaces like Co/Pt is still missing. In the case of Pt, recent studies have put forward the major role played by i) the spin-memory loss (SML) and the electronic transparency at 3d/5d interfaces and ii) the inhomogeneity of the conductivity in the current-in-plane (CIP) geometry to explain the discrepancy in the SHE. Ingredients to consider then are the profiles of both the conductivity and spin-current across the multilayers and spin-transmission. In this talk, we will present robust SMR measurements observed on NiCo/Pt multilayer stacks characterized by a perpendicular magnetic anisotropy (PMA). The SMR occurs for both in-plane magnetization rotation or from nominal out-of-plane to the in-plane direction transverse to the current flow. This clearly departs from standard AMR or pure interfacial anisotropic-AMR symmetries. We analyze in large details our SMR signals for the whole series of samples owing to two main guidelines: i) we consider the exact conductivity profile across the multilayers, in particular near the Co/Pt interface, via the Camley-Barnas approach and ii) we derive the spin current profile generated by SHE along the perpendicular direction responsible for SMR. We consider

  16. [Climate change and Kyoto protocol].

    PubMed

    Ergasti, G; Pippia, V; Murzilli, G; De Luca D'Alessandro, E

    2009-01-01

    Due to industrial revolution and the heavy use of fossil fuels, the concentration of greenhouse gases in the atmosphere has increased dramatically during the last hundred years, and this has lead to an increase in mean global temperature. The environmental consequences of this are: the melting of the ice caps, an increase in mean sea-levels, catastrophic events such as floodings, hurricanes and earthquakes, changes to the animal and vegetable kingdoms, a growth in vectors and bacteria in water thus increasing the risk of infectious diseases and damage to agriculture. The toxic effects of the pollution on human health are both acute and chronic. The Kyoto Protocol is an important step in the campaign against climatic changes but it is not sufficient. A possible solution might be for the States which produce the most of pollution to adopt a better political stance for the environment and to use renewable resources for the production of energy.

  17. Carbon emissions. The economic benefits of the Kyoto Protocol.

    PubMed

    De Leo, G A; Rizzi, L; Caizzi, A; Gatto, M

    2001-10-04

    The third Conference of the Parties in Kyoto set the target of reducing greenhouse-gas emissions by an average of 5.3% with respect to 1990 values by 2008-2012. One of the main objections to the protocol's ratification is that compliance would pose an unbearable economic burden on the countries involved. But we show here that this is not the case if costs apart from the direct costs of energy production are also considered. Costs are also incurred in rectifying damage to human health, material goods, agriculture and the environment related to greenhouse-gas emissions.

  18. The Kyoto Protocol: A business perspective

    SciTech Connect

    Malin, C.B.

    1998-01-19

    Governments have made a tentative start in responding to climate change. In marathon negotiating sessions that extended into an extra day Dec. 1--11 in Kyoto, Japan, representatives from more than 160 governments hammered out the Kyoto Protocol to the United Nations Framework Convention on Climate Change (FCCC). The protocol calls for developed countries to reduce emissions of greenhouse gases (GHGs) on averaged by 5.2% below 1990 levels by the years 2008--2012. Developing countries have no new obligations. The paper discusses the agreement, ratification, future questions, business role, and the challenge.

  19. Laurance David Hall.

    PubMed

    Coxon, Bruce

    2011-01-01

    An account is given of the life, scientific contributions, and passing of Laurance David Hall (1938-2009), including his early history and education at the University of Bristol, UK, and the synthesis and NMR spectroscopy of carbohydrates and other natural products during ∼20 years of research and teaching at the University of British Columbia in Vancouver, Canada. Lists of graduate students, post-doctoral fellows, and sabbatical visitors are provided for this period. Following a generous endowment by Dr. Herchel Smith, Professor Hall built a new Department of Medicinal Chemistry at Cambridge University, UK, and greatly expanded his researches into the technology and applications of magnetic resonance imaging (MRI) and zero quantum NMR. MRI technology was applied both to medical problems such as the characterization of cartilage degeneration in knee joints, the measurement of ventricular function, lipid localization in animal models of atherosclerosis, paramagnetic metal complexes of polysaccharides as contrast agents, and studies of many other anatomical features, but also to several aspects of materials analysis, including food analyses, process control, and the elucidation of such physical phenomena as the flow of liquids through porous media, defects in concrete, and the visualization of fungal damage to wood. Professor Hall's many publications, patents, lectures, and honors and awards are described, and also his successful effort to keep the Asilomar facility in Pacific Grove, California as the alternating venue for the annual Experimental NMR Conference. Two memorial services for Professor Hall are remembered.

  20. Insider conference tips

    NASA Astrophysics Data System (ADS)

    Tennant, Jill

    2012-01-01

    Attending an educator conference and its associated exhibit hall can be a rewarding experience for your brain. But if you keep in mind these insider's tips, your feet, arms, stomach, and wallet will also thank you.

  1. Increasing use of yellow colors in Kyoto

    NASA Astrophysics Data System (ADS)

    Akita, Munehira; Nara, Iwao

    2002-06-01

    Colors used for commercial signboards, displayed outdoors as well as indoors through windows, such as a store sign, an advertising sign, a sky sign, a poster, a placard, and a billboard were extensively surveyed in Kyoto City, Japan, in 1998. The survey showed that various kinds of yellow painted signs have increased rapidly and invaded a center area and suburbs of the city. Vivid yellow, what we called it the Y98 virus, is specially considered a color unpleasantly matched to the city image of Kyoto which was the capital of Japan for nearly 1000 years (794 to 1868) and is endowed with cultural and historic heritage. Discussions trying to find out what we could do to prevent the rapid spread of a big commercial display painted with vivid yellows what we called 'the Y98 virus' over the city will be summarized in a main text.

  2. Parks and People. A European Conference for Naturparke Parcs Naturels/National Parks (U.K.) and Equivalent Reserves (Losehill Hall, Castleton, England, September 25-29, 1978).

    ERIC Educational Resources Information Center

    Youel, Alex J.

    Presented are the proceedings of the European Conference for National Parks and Equivalent Reserves held at the Peak National Park Study Centre, Castleton, England in 1978. Thirty-nine representatives from 10 countries focused on the relationship between the parks and the people connected with them (the local people, the visitors, and the park…

  3. [Approach to Teaching Kampo Medicine at Kyoto Pharmaceutical University].

    PubMed

    Matsuda, Hisashi

    2016-01-01

    An approach to educating our pharmaceutical students about Kampo medicine in the six-year system of undergraduate pharmacy education at Kyoto Pharmaceutical University is introduced, including the author's opinions. Curriculum revisions have been made in our university for students entering after 2012. In teaching Kampo medicine at present, a medical doctor and an on-site pharmacist share information difficult to give in a lecture with the teaching staff in my laboratory. For example, before the curriculum revision, we conferred with a pharmacist and a doctor in the course "Kampo Medicine A, B" for 4th year students, in which students were presented a basic knowledge of Kampo medicine, the application of important Kampo medicines, combinations of crude drugs, etc. Further, in our "Introduction to Kampo Medicine" for 6th year students, presented after they have practiced in hospitals and community pharmacies, we again lecture on the pharmacological characteristics of Kampo medicines, on "pattern (Sho)", and on evidence-based medicine (EBM) and research studies of important Kampo medicines. After our curriculum revision, "Kampo Medicine A, B" was rearranged into the courses "Kampo and Pharmacognosy" and "Clinical Kampo Medicine". "Kampo and Pharmacognosy" is now provided in the second semester of the 3rd year, and in this course we lecture on the basic knowledge of Kampo medicine. An advanced lecture will be given on "Clinical Kampo Medicine" in the 6th year. We are searching for the best way to interest students in Kampo medicine, and to counteract any misunderstandings about Kampo medicine.

  4. Continuity and Change: Kyoto Chefs Engage with Science.

    PubMed

    de St Maurice, Greg

    2015-01-01

    Kyoto's chefs have reacted proactively to changes brought about by the most recent phase of globalization, hoping to ensure the continued existence and resonance of Kyoto cuisine by using science to adapt it to contemporary circumstances. These chefs are breaking new ground in their pursuit of a scientific understanding of how Kyoto cuisine works. They meet once a month in a kitchen laboratory at Kyoto University to present and analyze culinary experiments in keeping with a predetermined theme. They use their acquired knowledge to more precisely hone their culinary skills and to explain Kyoto cuisine to a global audience. Chefs visit local elementary schools, appear on national television, and welcome chefs from abroad into their kitchens so that people across the world will better understand what authentic Kyoto cuisine consists of. Although these chefs' efforts are groundbreaking, there is also remarkable continuity to their approach. Not only has Kyoto cuisine always been in a steady state of transformation, but the chefs in the Laboratory are engaging with science and a global audience specifically so that they can ascertain Kyoto cuisine's continued existence and importance. Though their means of understanding and articulating what Kyoto cuisine is differs from that of their predecessors, concepts like shun (seasonality) and hin (refinement) still guide chefs today. Ultimately, then, based on interviews and participant observation conducted in and outside of the Japanese Cuisine Laboratory in 2012 and 2013, I argue that by engaging with contemporary food science, Kyoto's chefs achieve a strategic balance of protecting their culinary heritage while adapting it to contemporary circumstances.

  5. KEGG: Kyoto Encyclopedia of Genes and Genomes.

    PubMed

    Ogata, H; Goto, S; Sato, K; Fujibuchi, W; Bono, H; Kanehisa, M

    1999-01-01

    Kyoto Encyclopedia of Genes and Genomes (KEGG) is a knowledge base for systematic analysis of gene functions in terms of the networks of genes and molecules. The major component of KEGG is the PATHWAY database that consists of graphical diagrams of biochemical pathways including most of the known metabolic pathways and some of the known regulatory pathways. The pathway information is also represented by the ortholog group tables summarizing orthologous and paralogous gene groups among different organisms. KEGG maintains the GENES database for the gene catalogs of all organisms with complete genomes and selected organisms with partial genomes, which are continuously re-annotated, as well as the LIGAND database for chemical compounds and enzymes. Each gene catalog is associated with the graphical genome map for chromosomal locations that is represented by Java applet. In addition to the data collection efforts, KEGG develops and provides various computational tools, such as for reconstructing biochemical pathways from the complete genome sequence and for predicting gene regulatory networks from the gene expression profiles. The KEGG databases are daily updated and made freely available (http://www.genome.ad.jp/kegg/).

  6. KEGG: kyoto encyclopedia of genes and genomes.

    PubMed

    Kanehisa, M; Goto, S

    2000-01-01

    KEGG (Kyoto Encyclopedia of Genes and Genomes) is a knowledge base for systematic analysis of gene functions, linking genomic information with higher order functional information. The genomic information is stored in the GENES database, which is a collection of gene catalogs for all the completely sequenced genomes and some partial genomes with up-to-date annotation of gene functions. The higher order functional information is stored in the PATHWAY database, which contains graphical representations of cellular processes, such as metabolism, membrane transport, signal transduction and cell cycle. The PATHWAY database is supplemented by a set of ortholog group tables for the information about conserved subpathways (pathway motifs), which are often encoded by positionally coupled genes on the chromosome and which are especially useful in predicting gene functions. A third database in KEGG is LIGAND for the information about chemical compounds, enzyme molecules and enzymatic reactions. KEGG provides Java graphics tools for browsing genome maps, comparing two genome maps and manipulating expression maps, as well as computational tools for sequence comparison, graph comparison and path computation. The KEGG databases are daily updated and made freely available (http://www. genome.ad.jp/kegg/).

  7. Impacts of the Kyoto protocol on U.S. energy markets and economic activity

    SciTech Connect

    1998-10-01

    The Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organization and the United Nations Environment Program in 1988 to assess the available scientific, technical, and socioeconomic information in the field of climate change. The most recent report of the IPCC concluded that ``Our ability to quantify the human influence on global climate is currently limited because the expected signal is still emerging from the noise of natural variability, and because there are uncertainties in key factors. These include the magnitudes and patterns of long-term variability and the time-evolving pattern of forcing by, and response to, changes in concentrations of greenhouse gases and aerosols, and land surface changes. Nevertheless the balance of evidence suggests that there is a discernible human influence on global climate. The first and second Conference of the Parties in 1995 and 1996 agreed to address the issue of greenhouse gas emissions for the period beyond 2000, and to negotiate quantified emission limitations and reductions for the third Conference of the Parties. On December 1 through 11, 1997, representatives from more than 160 countries met in Kyoto, Japan, to negotiate binding limits on greenhouse gas emissions for developed nations. The resulting Kyoto Protocol established emissions targets for each of the participating developed countries--the Annex 1 countries--relative to their 1990 emissions levels. 114 refs., 138 figs., 33 tabs.

  8. GPCR structure, function, drug discovery and crystallography: report from Academia-Industry International Conference (UK Royal Society) Chicheley Hall, 1-2 September 2014.

    PubMed

    Heifetz, Alexander; Schertler, Gebhard F X; Seifert, Roland; Tate, Christopher G; Sexton, Patrick M; Gurevich, Vsevolod V; Fourmy, Daniel; Cherezov, Vadim; Marshall, Fiona H; Storer, R Ian; Moraes, Isabel; Tikhonova, Irina G; Tautermann, Christofer S; Hunt, Peter; Ceska, Tom; Hodgson, Simon; Bodkin, Mike J; Singh, Shweta; Law, Richard J; Biggin, Philip C

    2015-08-01

    G-protein coupled receptors (GPCRs) are the targets of over half of all prescribed drugs today. The UniProt database has records for about 800 proteins classified as GPCRs, but drugs have only been developed against 50 of these. Thus, there is huge potential in terms of the number of targets for new therapies to be designed. Several breakthroughs in GPCRs biased pharmacology, structural biology, modelling and scoring have resulted in a resurgence of interest in GPCRs as drug targets. Therefore, an international conference, sponsored by the Royal Society, with world-renowned researchers from industry and academia was recently held to discuss recent progress and highlight key areas of future research needed to accelerate GPCR drug discovery. Several key points emerged. Firstly, structures for all three major classes of GPCRs have now been solved and there is increasing coverage across the GPCR phylogenetic tree. This is likely to be substantially enhanced with data from x-ray free electron sources as they move beyond proof of concept. Secondly, the concept of biased signalling or functional selectivity is likely to be prevalent in many GPCRs, and this presents exciting new opportunities for selectivity and the control of side effects, especially when combined with increasing data regarding allosteric modulation. Thirdly, there will almost certainly be some GPCRs that will remain difficult targets because they exhibit complex ligand dependencies and have many metastable states rendering them difficult to resolve by crystallographic methods. Subtle effects within the packing of the transmembrane helices are likely to mask and contribute to this aspect, which may play a role in species dependent behaviour. This is particularly important because it has ramifications for how we interpret pre-clinical data. In summary, collaborative efforts between industry and academia have delivered significant progress in terms of structure and understanding of GPCRs and will be

  9. SLA at 100: Conference Preview

    ERIC Educational Resources Information Center

    Blumenstein, Lynn

    2009-01-01

    When School Library Association (SLA) convenes its annual conference in Washington, DC, June 14-17, 2009, the association will be celebrating its 100th birthday. This occasion allows for grand gestures--the SLA Salutes! Awards and Leadership Reception will be held in the Library of Congress's Great Hall. The conference also draws upon Washington…

  10. Concert hall acoustics

    NASA Astrophysics Data System (ADS)

    Schroeder, Manfred

    2004-05-01

    I will review some work at Bell Laboratories on artificial reverberation and concert hall acoustics including Philharmonic Hall (Lincoln Center for the Performing Arts, New York). I will also touch on sound diffusion by number-theoretic surfaces and the measurement of reverberation time using the music as played in the hall as a ``test'' signal.

  11. Carbon Sequestered, Carbon Displaced and the Kyoto Context

    SciTech Connect

    Marland, G.; Schlamadinger, B.

    1999-04-18

    The integrated system that embraces forest management, forest products, and land-use change impacts the global carbon cycle - and hence the net emission of the greenhouse gas carbon dioxide - in four fundamental ways. Carbon is stored in living and dead biomass, carbon is stored in wood products and landfills, forest products substitute in the market place for products made from other materials, and forest harvests can be used wholly or partially to displace fossil fuels in the energy sector. Implementation of the Kyoto Protocol to the United Nations Framework Convention on Climate Change would result in the creation of international markets for carbon dioxide emissions credits, but the current Kyoto text does not treat all carbon identically. We have developed a carbon accounting model, GORCAM, to examine a variety of scenarios for land management and the production of forest products. In this paper we explore, for two simple scenarios of forest management, the carbon flows that occur and how these might be accounted for under the Kyoto text. The Kyoto protocol raises questions about what activities can result in emissions credits, which carbon reservoirs will be counted, who will receive the credits, and how much credit will be available? The Kyoto Protocol would sometimes give credits for carbon sequestered, but it would always give credits when fossil-fuel carbon dioxide emissions are displaced.

  12. Links between Cairo and Kyoto: addressing global warming through voluntary family planning.

    PubMed

    Skeer, Jeffrey

    2002-02-01

    Over the past three decades, with a combination of new technology, rising female literacy rates, and strengthened family planning programs, the world has seen dramatic increases in the use of contraception, with corresponding declines in fertility and population growth rates. At the International Conference on Population and Development, Cairo in 1994, parties pledged a tripling of funding for reproductive health programs in developing countries. Many demographers believe that making such programs more widely available to women would extend the decline in birth rates and shift the world towards the low scenario of United Nations population projections over the next century and a half. By examining the costs and impacts of such programs, in view of the links between population and carbon emissions, this paper shows that extension of voluntary family planning could make a large and cost-effective contribution to the greenhouse gas limitation goals of the Kyoto Protocol that was negotiated in 1997.

  13. Background Pressure Effects on Krypton Hall Effect Thruster Internal Acceleration

    DTIC Science & Technology

    2013-08-01

    Technical Paper 3. DATES COVERED (From - To) August 2013- September 2013 4. TITLE AND SUBTITLE Background Pressure Effects on Krypton Hall Effect...Conference 2013, Washington, D.C., 6-10 October 2013. 14. ABSTRACT This study uses krypton propellant in a medium power Hall effect to amplify the...effect of background pressure due to the greater mobility of neutral krypton compared to neutral xenon. The use of krypton amplifies the effect of

  14. National Brownfields Conference 2015 Summary Documents

    EPA Pesticide Factsheets

    The agenda for the local government roundtable, the town hall summary, and the Urban Waters presentation delivered by Mike Shapiro are here attached. All relate to this event, the National Brownfields Conference held in Chicago, IL on September 2, 2015.

  15. Hall Effect Spintronics

    DTIC Science & Technology

    2008-09-23

    resistance measurement, in which current sources can share a common ground, the Hall measurement requires electrically isolated current sources. It...8 Figure captions Fig. 1. Measurement setup for the non-switching van der Pauw Hall technique. IAC and IDB are electrically isolated...Longitudinal resistivity (measured along the electrical current) is expected to be an even function of magnetic induction B, whereas the transverse or Hall

  16. Ocean fertilization, carbon credits and the Kyoto Protocol

    NASA Astrophysics Data System (ADS)

    Westley, M. B.; Gnanadesikan, A.

    2008-12-01

    Commercial interest in ocean fertilization as a carbon sequestration tool was excited by the December 1997 agreement of the Kyoto Protocol to the United Nations Convention on Climate Change. The Protocol commits industrialized countries to caps on net greenhouse gas emissions and allows for various flexible mechanisms to achieve these caps in the most economically efficient manner possible, including trade in carbon credits from projects that reduce emissions or enhance sinks. The carbon market was valued at 64 billion in 2007, with the bulk of the trading (50 billion) taking place in the highly regulated European Union Emission Trading Scheme, which deals primarily in emission allowances in the energy sector. A much smaller amount, worth $265 million, was traded in the largely unregulated "voluntary" market (Capoor and Ambrosi 2008). As the voluntary market grows, so do calls for its regulation, with several efforts underway to set rules and standards for the sale of voluntary carbon credits using the Kyoto Protocol as a starting point. Four US-based companies and an Australian company currently seek to develop ocean fertilization technologies for the generation of carbon credits. We review these plans through the lens of the Kyoto Protocol and its flexible mechanisms, and examine whether and how ocean fertilization could generate tradable carbon credits. We note that at present, ocean sinks are not included in the Kyoto Protocol, and that furthermore, the Kyoto Protocol only addresses sources and sinks of greenhouse gases within national boundaries, making open-ocean fertilization projects a jurisdictional challenge. We discuss the negotiating history behind the limited inclusion of land use, land use change and forestry in the Kyoto Protocol and the controversy and eventual compromise concerning methodologies for terrestrial carbon accounting. We conclude that current technologies for measuring and monitoring carbon sequestration following ocean fertilization

  17. HALL EFFECT INVESTIGATIONS

    DTIC Science & Technology

    INTERMETALLIC COMPOUNDS, *SEMICONDUCTING FILMS, *THIN FILM STORAGE DEVICES, ANTIMONY ALLOYS, CRYSTALLIZATION, ELECTRODES, ELECTROMAGNETIC PROPERTIES, EVAPORATION, HALL EFFECT , HEAT TREATMENT, INDIUM ALLOYS, ELECTRICAL RESISTANCE.

  18. 52. GREAT HALL, LOOKING NORTH THROUGH STAIR HALL TO NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    52. GREAT HALL, LOOKING NORTH THROUGH STAIR HALL TO NORTH VESTIBULE DOORS - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  19. Hall effect in hopping regime

    NASA Astrophysics Data System (ADS)

    Avdonin, A.; Skupiński, P.; Grasza, K.

    2016-02-01

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO.

  20. Hall of Fame.

    ERIC Educational Resources Information Center

    El Rancho Unified School District, Pico Rivera, CA.

    A Hall of Fame was established by the El Rancho Unified School District (California) to identify and honor graduates of the school district who have graduated more than 15 years ago, who have achieved recognition in their chosen field, and who would bring honor to the school district in its honoring of them. Nominees for the Hall of Fame were…

  1. The Hall Effect

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The experimental procedure consists of the measurement of the Hall coefficient, resistivity, and Hall mobility as a function of temperature of a sample of gallium arsenides before and after irradiation with low and high energy protons. Work has begun on the development of the theory and subsequently experiments will be designed and performed.

  2. Skyrmions and Hall Transport.

    PubMed

    Kim, Bom Soo; Shapere, Alfred D

    2016-09-09

    We derive a generalized set of Ward identities that captures the effects of topological charge on Hall transport. The Ward identities follow from the (2+1)-dimensional momentum algebra, which includes a central extension proportional to the topological charge density. In the presence of topological objects like Skyrmions, we observe that the central term leads to a direct relation between the thermal Hall conductivity and the topological charge density. We extend this relation to incorporate the effects of a magnetic field and an electric current. The topological charge density produces a distinct signature in the electric Hall conductivity, which is identified in existing experimental data and yields further novel predictions. For insulating materials with translation invariance, the Hall viscosity can be directly determined from the Skyrmion density and the thermal Hall conductivity to be measured as a function of momentum.

  3. Pulsed hall thruster system

    NASA Technical Reports Server (NTRS)

    Hruby, Vladimir J. (Inventor); Pote, Bruce M. (Inventor); Gamero-Castano, Manuel (Inventor)

    2004-01-01

    A pulsed Hall thruster system includes a Hall thruster having an electron source, a magnetic circuit, and a discharge chamber; a power processing unit for firing the Hall thruster to generate a discharge; a propellant storage and delivery system for providing propellant to the discharge chamber and a control unit for defining a pulse duration .tau.<0.1d.sup.3.rho./m, where d is the characteristic size of the thruster, .rho. is the propellant density at standard conditions, and m is the propellant mass flow rate for operating either the power processing unit to provide to the Hall thruster a power pulse of a pre-selected duration, .tau., or operating the propellant storage and delivery system to provide a propellant flow pulse of duration, .tau., or providing both as pulses, synchronized to arrive coincidentally at the discharge chamber to enable the Hall thruster to produce a discreet output impulse.

  4. Skyrmions and Hall Transport

    NASA Astrophysics Data System (ADS)

    Kim, Bom Soo; Shapere, Alfred D.

    2016-09-01

    We derive a generalized set of Ward identities that captures the effects of topological charge on Hall transport. The Ward identities follow from the (2 +1 )-dimensional momentum algebra, which includes a central extension proportional to the topological charge density. In the presence of topological objects like Skyrmions, we observe that the central term leads to a direct relation between the thermal Hall conductivity and the topological charge density. We extend this relation to incorporate the effects of a magnetic field and an electric current. The topological charge density produces a distinct signature in the electric Hall conductivity, which is identified in existing experimental data and yields further novel predictions. For insulating materials with translation invariance, the Hall viscosity can be directly determined from the Skyrmion density and the thermal Hall conductivity to be measured as a function of momentum.

  5. Remote Sensing and the Kyoto Protocol: A Workshop Summary

    NASA Technical Reports Server (NTRS)

    Rosenqvist, Ake; Imhoff, Marc; Milne, Anthony; Dobson, Craig

    2000-01-01

    The Kyoto Protocol to the United Nations Framework Convention on Climate Change contains quantified, legally binding commitments to limit or reduce greenhouse gas emissions to 1990 levels and allows carbon emissions to be balanced by carbon sinks represented by vegetation. The issue of using vegetation cover as an emission offset raises a debate about the adequacy of current remote sensing systems and data archives to both assess carbon stocks/sinks at 1990 levels, and monitor the current and future global status of those stocks. These concerns and the potential ratification of the Protocol among participating countries is stimulating policy debates and underscoring a need for the exchange of information between the international legal community and the remote sensing community. On October 20-22 1999, two working groups of the International Society for Photogrammetry and Remote Sensing (ISPRS) joined with the University of Michigan (Michigan, USA) to convene discussions on how remote sensing technology could contribute to the information requirements raised by implementation of, and compliance with, the Kyoto Protocol. The meeting originated as a joint effort between the Global Monitoring Working Group and the Radar Applications Working Group in Commission VII of the ISPRS, co-sponsored by the University of Michigan. Tile meeting was attended by representatives from national government agencies and international organizations and academic institutions. Some of the key themes addressed were: (1) legal aspects of transnational remote sensing in the context of the Kyoto Protocol; (2) a review of the current and future and remote sensing technologies that could be applied to the Kyoto Protocol; (3) identification of areas where additional research is needed in order to advance and align remote sensing technology with the requirements and expectations of the Protocol; and 94) the bureaucratic and research management approaches needed to align the remote sensing

  6. PREFACE: 15th International Conference on Thin Films (ICTF-15)

    NASA Astrophysics Data System (ADS)

    Takai, Osamu; Saito, Nagahiro; Zettsu, Nobuyuki; Cho, Sung-Pyo; Terashima, Chiaki; Ueno, Tomonaga; Sakai, Osamu; Miyazaki, Seiichi; Yoshimura, Kazuki; Akamatsu, Kensuke; Ito, Takahiro; Yogo, Toshinobu; Inoue, Yasushi; Ohtake, Naoto; Yoshida, Tsukasa; Tosa, Masahiro; Takai, Madoka; Fujiwara, Yasufumi; Matsuda, Naoki; Teshima, Katsuya; Seki, Takahiro; Matsunaga, Katsuyuki; Fujita, Daisuke

    2013-03-01

    The International Conference on Thin Films is the most established conference for all researchers and persons interested in thin films and coatings. It is one of the tri-annual conference series endorsed and co-organized by the Thin Film Division of the International Union for Vacuum Science, Technique and Applications (IUVSTA), a union of national member societies whose role is to stimulate international collaboration in the fields of vacuum science, techniques and applications and related multi-disciplinary topics including solid-vacuum and other interfaces. The 15th International Conference on Thin Films (ICTF-15) is organized by The Vacuum Society of Japan (VSJ) and held at Kyoto TERRSA in Kyoto, Japan on 8-11 November 2011, following the 14th International Conference on Thin Films (ICTF-14), which was held in Ghent, Belgium in 2008. Thin films and coatings are daily becoming increasingly important in the fields of various industries. This International Conference provides a multi-disciplinary forum for recent advances in basic research, development and applications of thin films and coatings. This conference will present a unique opportunity for researchers, engineers and managers to acquire new knowledge of thin films and coatings. We hope that our understanding on thin films and coatings will be deepened through this conference. The conference site, 'Kyoto TERRSA' is located in the historical heart of the old capital Kyoto. Kyoto is an ancient city with a 1200-year history. It was established as Japan's capital under the name 'Heian-kyo' in the year 794. Although many transformations have taken place over the years, Kyoto has always embraced the most advanced standards of the times. It has greatly contributed to the nation's industrial, economic and cultural development. The dauntless spirit of leadership of Kyoto's past as a capital city is still felt here today. Kyoto also preserves the beloved examples of its culture as testimonials of time. This is shown

  7. Non-Kyoto Radiative Forcing in Long-Run Greenhouse Gas Emissions and Climate Change Scenarios

    SciTech Connect

    Rose, Steven K.; Richels, Richard G.; Smith, Steven J.; Riahi, Keywan; Stefler, Jessica; Van Vuuren, Detlef

    2014-04-27

    Climate policies designed to achieve climate change objectives must consider radiative forcing from the Kyoto greenhouse gas, as well as other forcing constituents, such as aerosols and tropospheric ozone. Net positive forcing leads to global average temperature increases. Modeling of non-Kyoto forcing is a relatively new component of climate management scenarios. Five of the nineteen models in the EMF-27 Study model both Kyoto and non-Kyoto forcing. This paper describes and assesses current non-Kyoto radiative forcing modeling within these integrated assessment models. The study finds negative forcing from aerosols masking significant positive forcing in reference non-climate policy projections. There are however large differences across models in projected non-Kyoto emissions and forcing, with differences stemming from differences in relationships between Kyoto and non-Kyoto emissions and fundamental differences in modeling structure and assumptions. Air pollution and non-Kyoto forcing decline in the climate policy scenarios. However, non-Kyoto forcing appears to be influencing mitigation results, including allowable carbon dioxide emissions, and further evaluation is merited. Overall, there is substantial uncertainty related to non-Kyoto forcing that must be considered.

  8. Facilty Focus: Residence Halls.

    ERIC Educational Resources Information Center

    Hunnewell, James F., Jr.

    2002-01-01

    Describes the Western Ridge Residence at Colorado College and Beard Hall at Wheaton College. The buildings feature multiple levels that take advantage of views and also help create a "homey" feeling. (EV)

  9. Hall Effect Spintronics

    DTIC Science & Technology

    2011-04-01

    spin-transfer torque gives rise to magnetization reversal and excitation of spin-waves in ferromagnet /normal- metal / ferromagnet trilayers (F/N/F...applications based on the extraordinary Hall effect (EHE). The work was focused on three major tasks: 1. Preparation and study of CoPd multilayers ...D. Rosenblatt, M. Karpovski and A. Gerber, Reversal of the Extraordinary Hall Effect polarity in thin Co-Pd multilayers ., Appl. Phys. Lett., 96

  10. Let`s focus on sustainability, not Kyoto

    SciTech Connect

    Linden, H.R.

    1999-03-01

    This article addresses how to reduce the emissions of carbon dioxide produced in the combustion of fossil fuels -- oil, natural gas, and coal -- in a less painful way than that called for in the Kyoto Protocol. Adopting a 1,000-gigatonne global carbon budget for years 1991 to 2100 and a peak annual carbon emission level of 11 gigatonnes between years 2030 and 2040 will buy the time to develop and deploy low- and zero-carbon emission technologies while deferring the controversial issue of the compliance of developing countries.

  11. Nonlocal Anomalous Hall Effect.

    PubMed

    Zhang, Steven S-L; Vignale, Giovanni

    2016-04-01

    The anomalous Hall (AH) effect is deemed to be a unique transport property of ferromagnetic metals, caused by the concerted action of spin polarization and spin-orbit coupling. Nevertheless, recent experiments have shown that the effect also occurs in a nonmagnetic metal (Pt) in contact with a magnetic insulator [yttrium iron garnet (YIG)], even when precautions are taken to ensure that there is no induced magnetization in the metal. We propose a theory of this effect based on the combined action of spin-dependent scattering from the magnetic interface and the spin-Hall effect in the bulk of the metal. At variance with previous theories, we predict the effect to be of first order in the spin-orbit coupling, just as the conventional anomalous Hall effect-the only difference being the spatial separation of the spin-orbit interaction and the magnetization. For this reason we name this effect the nonlocal anomalous Hall effect and predict that its sign will be determined by the sign of the spin-Hall angle in the metal. The AH conductivity that we calculate from our theory is in order of magnitude agreement with the measured values in Pt/YIG structures.

  12. Nonlocal Anomalous Hall Effect

    NASA Astrophysics Data System (ADS)

    Zhang, Steven S.-L.; Vignale, Giovanni

    2016-04-01

    The anomalous Hall (AH) effect is deemed to be a unique transport property of ferromagnetic metals, caused by the concerted action of spin polarization and spin-orbit coupling. Nevertheless, recent experiments have shown that the effect also occurs in a nonmagnetic metal (Pt) in contact with a magnetic insulator [yttrium iron garnet (YIG)], even when precautions are taken to ensure that there is no induced magnetization in the metal. We propose a theory of this effect based on the combined action of spin-dependent scattering from the magnetic interface and the spin-Hall effect in the bulk of the metal. At variance with previous theories, we predict the effect to be of first order in the spin-orbit coupling, just as the conventional anomalous Hall effect—the only difference being the spatial separation of the spin-orbit interaction and the magnetization. For this reason we name this effect the nonlocal anomalous Hall effect and predict that its sign will be determined by the sign of the spin-Hall angle in the metal. The AH conductivity that we calculate from our theory is in order of magnitude agreement with the measured values in Pt /YIG structures.

  13. NASA's Hall Thruster Program

    NASA Technical Reports Server (NTRS)

    Jankovsky, Robert S.; Jacobson, David T.; Rawlin, Vincent K.; Mason, Lee S.; Mantenieks, Maris A.; Manzella, David H.; Hofer, Richard R.; Peterson, Peter Y.

    2001-01-01

    NASA's Hall thruster program has base research and focused development efforts in support of the Advanced Space Transportation Program, Space-Based Program, and various other programs. The objective of the base research is to gain an improved understanding of the physical processes and engineering constraints of Hall thrusters to enable development of advanced Hall thruster designs. Specific technical questions that are current priorities of the base effort are: (1) How does thruster life vary with operating point? (2) How can thruster lifetime and wear rate be most efficiently evaluated? (3) What are the practical limitations for discharge voltage as it pertains to high specific impulse operation (high discharge voltage) and high thrust operation (low discharge voltage)? (4) What are the practical limits for extending Hall thrusters to very high input powers? and (5) What can be done during thruster design to reduce cost and integration concerns? The objective of the focused development effort is to develop a 50 kW-class Hall propulsion system, with a milestone of a 50 kW engineering model thruster/system by the end of program year 2006. Specific program wear 2001 efforts, along with the corporate and academic participation, are described.

  14. Conducting Wall Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Goebel, Dan M.; Hofer, Richard R.; Mikellides, Ioannis G.; Katz, Ira; Polk, James E.; Dotson, Brandon

    2013-01-01

    A unique configuration of the magnetic field near the wall of Hall thrusters, called Magnetic Shielding, has recently demonstrated the ability to significantly reduce the erosion of the boron nitride (BN) walls and extend the life of Hall thrusters by orders of magnitude. The ability of magnetic shielding to minimize interactions between the plasma and the discharge chamber walls has for the first time enabled the replacement of insulating walls with conducting materials without loss in thruster performance. The boron nitride rings in the 6 kW H6 Hall thruster were replaced with graphite that self-biased to near the anode potential. The thruster efficiency remained over 60% (within two percent of the baseline BN configuration) with a small decrease in thrust and increase in Isp typical of magnetically shielded Hall thrusters. The graphite wall temperatures decreased significantly compared to both shielded and unshielded BN configurations, leading to the potential for higher power operation. Eliminating ceramic walls makes it simpler and less expensive to fabricate a thruster to survive launch loads, and the graphite discharge chamber radiates more efficiently which increases the power capability of the thruster compared to conventional Hall thruster designs.

  15. GHG emission reductions and costs to achieve Kyoto target.

    PubMed

    Chen, Wen-ying

    2003-07-01

    Emission projection and marginal abatement cost curves (MACs) are the central components of any assessment of future carbon market, such as CDM (clean development mechanism) potentials, carbon quota price etc. However, they are products of very complex, dynamic systems driven by forces like population growth, economic development, resource endowments, technology progress and so on. The modeling approaches for emission projection and MACs evaluation were summarized, and some major models and their results were compared. Accordingly, reduction and cost requirements to achieve the Kyoto target were estimated. It is concluded that Annex I Parties' total reduction requirements range from 503-1304 MtC with USA participation and decrease significantly to 140-612 MtC after USA's withdrawal. Total costs vary from 21-77 BUSD with USA and from 5-36 BUSD without USA if only domestic reduction actions are taken. The costs would sharply reduce while considering the three flexible mechanisms defined in the Kyoto Protocol with domestic actions' share in the all mitigation strategies drops to only 0-16% .

  16. After Kyoto, science still probes global warming causes

    SciTech Connect

    Westbrook, G.

    1998-01-19

    The Kyoto meeting has come and gone. In the US, the treaty still has to be signed by President Bill Clinton and ratified by the Senate, an action that is most unlikely in view of last year`s 95-0 vote on the issue. In the short term 36 senators are up for reelection in November and therefore likely to come under intense pressure to change their positions, to support the Kyoto treaty, and to push for Senate action. Senators will need support, additional inputs, and overall reinforcement of their positions. One area that this writer believes still has much to offer in this context is the quality--more specifically, the lack of quality--of much of the scientific evidence behind this treaty. Part of that subject is the natural variability in the climate. Natural climate variability is based on cyclical forces, random events, and the Earth`s response to these two factors. These forces create the variability in the climate, the background noise above which any signal of anthropogenic warming must rise in order to be detected. A review of key climatic cycles is the subject of this article.

  17. High Power Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Jankovsky, Robert; Tverdokhlebov, Sergery; Manzella, David

    1999-01-01

    The development of Hall thrusters with powers ranging from tens of kilowatts to in excess of one hundred kilowatts is considered based on renewed interest in high power. high thrust electric propulsion applications. An approach to develop such thrusters based on previous experience is discussed. It is shown that the previous experimental data taken with thrusters of 10 kW input power and less can be used. Potential mass savings due to the design of high power Hall thrusters are discussed. Both xenon and alternate thruster propellant are considered, as are technological issues that will challenge the design of high power Hall thrusters. Finally, the implications of such a development effort with regard to ground testing and spacecraft intecrati'on issues are discussed.

  18. Model of Hall Reconnection

    SciTech Connect

    Malyshkin, Leonid M.

    2008-11-28

    The rate of quasistationary, two-dimensional magnetic reconnection is calculated in the framework of incompressible Hall magnetohydrodynamics, which includes the Hall and electron pressure terms in Ohm's law. The Hall-magnetohydrodynamics equations are solved in a local region across the reconnection electron layer, including only the upstream region and the layer center. In the case when the ion inertial length d{sub i} is larger than the Sweet-Parker reconnection layer thickness, the dimensionless reconnection rate is found to be independent of the electrical resistivity and equal to d{sub i}/L, where L is the scale length of the external magnetic field in the upstream region outside the electron layer and the ion layer thickness is found to be d{sub i}.

  19. Model of Hall reconnection.

    PubMed

    Malyshkin, Leonid M

    2008-11-28

    The rate of quasistationary, two-dimensional magnetic reconnection is calculated in the framework of incompressible Hall magnetohydrodynamics, which includes the Hall and electron pressure terms in Ohm's law. The Hall-magnetohydrodynamics equations are solved in a local region across the reconnection electron layer, including only the upstream region and the layer center. In the case when the ion inertial length di is larger than the Sweet-Parker reconnection layer thickness, the dimensionless reconnection rate is found to be independent of the electrical resistivity and equal to di/L, where L is the scale length of the external magnetic field in the upstream region outside the electron layer and the ion layer thickness is found to be di.

  20. European Heritage Landscapes. An Account of the Conference on Planning and Management in European Naturparke/Parcs Naturels/National Parks (U.K.) and Equivalent Category "C" Reserves (Losehill Hall, Castleton, England, September 26-30, 1977).

    ERIC Educational Resources Information Center

    Smith, Roland

    Presented are the proceedings of the Conference on Planning and Management in European National Parks and equivalent Category "C" reserves held at the Peak National Park Study Center, Castleton, England, in 1977. Fifty-two representatives from 16 countries focused practical solutions to management and planning problems in national parks. (BT)

  1. Hall Effect in a Plasma.

    ERIC Educational Resources Information Center

    Kunkel, W. B.

    1981-01-01

    Describes an apparatus and procedure for conducting an undergraduate laboratory experiment to quantitatively study the Hall effect in a plasma. Includes background information on the Hall effect and rationale for conducting the experiment. (JN)

  2. UNFINISHED BUSINESS: The Economics of The Kyoto Protocol

    SciTech Connect

    JA Edmonds; CN MacCracken; RD Sands; SH Kim

    2000-07-06

    The Kyoto Protocol to the Framework Convention on Climate Change (FCCC) was completed on the morning of December 11, 1997, following over two years of negotiations. The product of these deliberations is a complex and incomplete document knitting together the diversity of interests and perspectives represented by the more than 150 delegations. Because the document is complex, its implications are not immediately obvious. If it enters into force, the Kyoto Protocol will have far-reaching implications for all nations--both nations with obligations under the Protocol and those without obligations. National energy systems, and the world's energy system, could be forever changed. In this paper the authors develop an assessment of the energy and economic implications of achieving the goals of the Kyoto Protocol. They find that many of the details of the Protocol that remain to be worked out introduce critical uncertainties affecting the cost of compliance. There are also a variety of uncertainties that further complicate the analysis. These include future non-CO{sub 2} greenhouse gas emissions and the cost of their mitigation. Other uncertainties include the resolution of negotiations to establish rules for determining and allocating land-use emissions rights, mechanisms for Annex 1 trading, and participation by non-Annex 1 members in the Clean Development Mechanism. In addition, there are economic uncertainties, such as the behavior of Eastern Europe and the former Soviet Union in supplying emissions credits under Annex 1 trading. These uncertainties in turn could affect private sector investments in anticipation of the Protocol's entrance into force. The longer the nature of future obligations remains unclear, the less able decision makers will be to incorporate these rules into their investment decisions. They find that the cost of implementing the Protocol in the US can vary by more than an order of magnitude. The marginal cost could be as low as $26 per tonne of

  3. Strained graphene Hall bar

    NASA Astrophysics Data System (ADS)

    Milovanović, S. P.; Peeters, F. M.

    2017-02-01

    The effects of strain, induced by a Gaussian bump, on the magnetic field dependent transport properties of a graphene Hall bar are investigated. The numerical simulations are performed using both classical and quantum mechanical transport theory and we found that both approaches exhibit similar characteristic features. The effects of the Gaussian bump are manifested by a decrease of the bend resistance, R B, around zero-magnetic field and the occurrence of side-peaks in R B. These features are explained as a consequence of bump-assisted scattering of electrons towards different terminals of the Hall bar. Using these features we are able to give an estimate of the size of the bump. Additional oscillations in R B are found in the quantum description that are due to the population/depopulation of Landau levels. The bump has a minor influence on the Hall resistance even for very high values of the pseudo-magnetic field. When the bump is placed outside the center of the Hall bar valley polarized electrons can be collected in the leads.

  4. Residence Hall Fires.

    ERIC Educational Resources Information Center

    Wright, Dorothy

    1999-01-01

    Discusses how one college's experience with a tragic fire in one of its residence halls prompted a reevaluation of its fire-prevention-and-response strategies. Staff training, sprinkler installation, new alarm systems, and exit hardware to help make building exiting more efficient are discussed. (GR)

  5. The Monty Hall Dilemma.

    ERIC Educational Resources Information Center

    Granberg, Donald; Brown, Thad A.

    1995-01-01

    Examines people's behavior in the Monty Hall Dilemma (MHD), in which a person must make two decisions to win a prize. In a series of five studies, found that people misapprehend probabilities in the MHD. Discusses the MHD's relation to illusion of control, belief perseverance, and the status quo bias. (RJM)

  6. Hall Sweet Home

    ERIC Educational Resources Information Center

    Oguntoyinbo, Lekan

    2011-01-01

    Many urban and commuter universities have their sights set on students who are unlikely to connect with the college and likely to fail unless the right strategies are put in place to help them graduate. In efforts to improve retention rates, commuter colleges are looking to an unusual suspect: residence halls. The author discusses how these…

  7. Nonlocal anomalous Hall effect

    NASA Astrophysics Data System (ADS)

    Zhang, Shulei; Vignale, Giovanni

    Anomalous Hall effect (AHE) is a distinctive transport property of ferromagnetic metals arising from spin orbit coupling (SOC) in concert with spontaneous spin polarization. Nonetheless, recent experiments have shown that the effect also appears in a nonmagnetic metal in contact with a magnetic insulator. The main puzzle lies in the apparent absence of spin polarized electrons in the non-magnetic metal. Here, we theoretically demonstrate that the scattering of electrons from a rough metal-insulator interface is generally spin-dependent, which results in mutual conversion between spin and charge currents flowing in the plane of the layer. It is the current-carrying spin polarized electrons and the spin Hall effect in the bulk of the metal layer that conspire to generate the AH current. This novel AHE differs from the conventional one only in the spatial separation of the SOC and the magnetization, so we name it as nonlocal AHE. In contrast to other previously proposed mechanisms (e.g., spin Hall AHE and magnetic proximity effect (MPE)), the nonlocal AHE appears on the first order of spin Hall angle and does not rely on the induced moments in the metal layer, which make it experimentally detectable by contrasting the AH current directions of two layered structures such as Pt/Cu/YIG and β -Ta/Cu/YIG (with a thin inserted Cu layer to eliminate the MPE). We predict that the directions of the AH currents in these two trilayers would be opposite since the spin Hall angles of Pt and β -Ta are of opposite signs. Work supported by NSF Grants DMR-1406568.

  8. Positron beam facility at Kyoto University Research Reactor

    NASA Astrophysics Data System (ADS)

    Xu, Q.; Sato, K.; Yoshiie, T.; Sano, T.; Kawabe, H.; Nagai, Y.; Nagumo, K.; Inoue, K.; Toyama, T.; Oshima, N.; Kinomura, A.; Shirai, Y.

    2014-04-01

    A positron beam facility is presently under construction at the Kyoto University Research Reactor (KUR), which is a light-water moderated tank-type reactor operated at a rated thermal power of 5 MW. A cadmium (Cd) - tungsten (W) source similar to that used in NEPOMUC was chosen in the KUR because Cd is very efficient at producing γ-rays when exposed to thermal neutron flux, and W is a widely used in converter and moderator materials. High-energy positrons are moderated by a W moderator with a mesh structure. Electrical lenses and a solenoid magnetic field are used to extract the moderated positrons and guide them to a platform outside of the reactor, respectively. Since Japan is an earthquake-prone country, a special attention is paid for the design of the in-pile positron source so as not to damage the reactor in the severe earthquake.

  9. NASA's 2004 Hall Thruster Program

    NASA Technical Reports Server (NTRS)

    Jacobson, David T.; Manzella, David H.; Hofer, Richard R.; Peterson, Peter Y.

    2004-01-01

    An overview of NASA's Hall thruster research and development tasks conducted during fiscal year 2004 is presented. These tasks focus on: raising the technology readiness level of high power Hall thrusters, developing a moderate-power/ moderate specific impulse Hall thruster, demonstrating high-power/high specific impulse Hall thruster operation, and addressing the fundamental technical challenges of emerging Hall thruster concepts. Programmatic background information, technical accomplishments and out year plans for each program element performed under the sponsorship of the In-Space Transportation Program, Project Prometheus, and the Energetics Project are provided.

  10. Kyoto global consensus report on Helicobacter pylori gastritis

    PubMed Central

    Sugano, Kentaro; Tack, Jan; Kuipers, Ernst J; Graham, David Y; El-Omar, Emad M; Miura, Soichiro; Haruma, Ken; Asaka, Masahiro; Uemura, Naomi; Malfertheiner, Peter

    2015-01-01

    Objective To present results of the Kyoto Global Consensus Meeting, which was convened to develop global consensus on (1) classification of chronic gastritis and duodenitis, (2) clinical distinction of dyspepsia caused by Helicobacter pylori from functional dyspepsia, (3) appropriate diagnostic assessment of gastritis and (4) when, whom and how to treat H. pylori gastritis. Design Twenty-three clinical questions addressing the above-mentioned four domains were drafted for which expert panels were asked to formulate relevant statements. A Delphi method using an anonymous electronic system was adopted to develop the consensus, the level of which was predefined as ≥80%. Final modifications of clinical questions and consensus were achieved at the face-to-face meeting in Kyoto. Results All 24 statements for 22 clinical questions after extensive modifications and omission of one clinical question were achieved with a consensus level of >80%. To better organise classification of gastritis and duodenitis based on aetiology, a new classification of gastritis and duodenitis is recommended for the 11th international classification. A new category of H. pylori-associated dyspepsia together with a diagnostic algorithm was proposed. The adoption of grading systems for gastric cancer risk stratification, and modern image-enhancing endoscopy for the diagnosis of gastritis, were recommended. Treatment to eradicate H. pylori infection before preneoplastic changes develop, if feasible, was recommended to minimise the risk of more serious complications of the infection. Conclusions A global consensus for gastritis was developed for the first time, which will be the basis for an international classification system and for further research on the subject. PMID:26187502

  11. PREFACE: International Conference on Magnetism (ICM 2009)

    NASA Astrophysics Data System (ADS)

    Goll, Gernot; Löhneysen, Hilbert v.; Loidl, Alois; Pruschke, Thomas; Richter, Manuel; Schultz, Ludwig; Sürgers, Christoph; Wosnitza, Jochen

    2010-11-01

    The International Conference on Magnetism 2009 (ICM 2009) was held in Karlsruhe, Germany, from 26-31 July 2009. Previous conferences in this series were organized in Edingburgh, United Kingdom (1991), Warsaw, Poland (1994), Cairns, Australia (1997), Recife, Brazil (2000), Rome, Italy (2003) and Kyoto, Japan (2006). As with previous ICM conferences, the annual Conference on Strongly Correlated Electron Systems (SCES) was integrated into ICM 2009. Conference photograph Participants of ICM 2009 in front of the Stadthalle Karlsruhe. Topics of ICM 2009 were: Strongly Correlated Electron Systems; Quantum and Classical Spin Systems; Magnetic Structures and Interactions; Magnetization Dynamics and Micromagnetics; Spin-Dependent Transport; Spin Electronics; Magnetic Thin Films, Particles, and Nanostructures; Soft and Hard Magnetic Materials and their Applications; Novel Materials and Device Applications; Magnetic Recording and Memories; Measuring Techniques and Instrumentation, as well as Interdisciplinary Topics. We are grateful to the International Advisory Committee for their help in putting up an attractive program encompassing practically all aspects of magnetism, both experimentally and theoretically. The program committee comprised A Loidl, Germany (Chair), M A Continentino, Brazil, D E Dahlberg, USA, D Givord, France, G Güntherodt, Germany, H Mikeska, Germany, D Kaczorowski, Poland, Ching-Ray Chang, South Korea, I Mertig, Germany, D Vollhardt, Germany and E F Wassermann, Germany was also head of the National Organizing Committee. His help is gratefully acknowledged. Photographs Left: Poster session in the Stadthalle Karlsruhe. Upper right: H v Löhneysen (Conference Chairman), Nobel Laureates A Fert and P. Grünberg, E Umbach (Chairman of the Executive Board of Forschungszentrum Karlsruhe) (left to right). Lower right: Nobel Laureate P W Anderson. The scientific program started on Monday 27 July 2009 with opening addresses by the Conference Chairman, the deputy

  12. Spin Hall effects

    NASA Astrophysics Data System (ADS)

    Sinova, Jairo; Valenzuela, Sergio O.; Wunderlich, J.; Back, C. H.; Jungwirth, T.

    2015-10-01

    Spin Hall effects are a collection of relativistic spin-orbit coupling phenomena in which electrical currents can generate transverse spin currents and vice versa. Despite being observed only a decade ago, these effects are already ubiquitous within spintronics, as standard spin-current generators and detectors. Here the theoretical and experimental results that have established this subfield of spintronics are reviewed. The focus is on the results that have converged to give us the current understanding of the phenomena, which has evolved from a qualitative to a more quantitative measurement of spin currents and their associated spin accumulation. Within the experimental framework, optical-, transport-, and magnetization-dynamics-based measurements are reviewed and linked to both phenomenological and microscopic theories of the effect. Within the theoretical framework, the basic mechanisms in both the extrinsic and intrinsic regimes are reviewed, which are linked to the mechanisms present in their closely related phenomenon in ferromagnets, the anomalous Hall effect. Also reviewed is the connection to the phenomenological treatment based on spin-diffusion equations applicable to certain regimes, as well as the spin-pumping theory of spin generation used in many measurements of the spin Hall angle. A further connection to the spin-current-generating spin Hall effect to the inverse spin galvanic effect is given, in which an electrical current induces a nonequilibrium spin polarization. This effect often accompanies the spin Hall effect since they share common microscopic origins. Both can exhibit the same symmetries when present in structures comprising ferromagnetic and nonmagnetic layers through their induced current-driven spin torques or induced voltages. Although a short chronological overview of the evolution of the spin Hall effect field and the resolution of some early controversies is given, the main body of this review is structured from a pedagogical

  13. Cylindrical geometry hall thruster

    DOEpatents

    Raitses, Yevgeny; Fisch, Nathaniel J.

    2002-01-01

    An apparatus and method for thrusting plasma, utilizing a Hall thruster with a cylindrical geometry, wherein ions are accelerated in substantially the axial direction. The apparatus is suitable for operation at low power. It employs small size thruster components, including a ceramic channel, with the center pole piece of the conventional annular design thruster eliminated or greatly reduced. Efficient operation is accomplished through magnetic fields with a substantial radial component. The propellant gas is ionized at an optimal location in the thruster. A further improvement is accomplished by segmented electrodes, which produce localized voltage drops within the thruster at optimally prescribed locations. The apparatus differs from a conventional Hall thruster, which has an annular geometry, not well suited to scaling to small size, because the small size for an annular design has a great deal of surface area relative to the volume.

  14. Quantum hall ferromagnets

    NASA Astrophysics Data System (ADS)

    Kumar, Akshay

    We study several quantum phases that are related to the quantum Hall effect. Our initial focus is on a pair of quantum Hall ferromagnets where the quantum Hall ordering occurs simultaneously with a spontaneous breaking of an internal symmetry associated with a semiconductor valley index. In our first example ---AlAs heterostructures--- we study domain wall structure, role of random-field disorder and dipole moment physics. Then in the second example ---Si(111)--- we show that symmetry breaking near several integer filling fractions involves a combination of selection by thermal fluctuations known as "order by disorder" and a selection by the energetics of Skyrme lattices induced by moving away from the commensurate fillings, a mechanism we term "order by doping". We also study ground state of such systems near filling factor one in the absence of valley Zeeman energy. We show that even though the lowest energy charged excitations are charge one skyrmions, the lowest energy skyrmion lattice has charge > 1 per unit cell. We then broaden our discussion to include lattice systems having multiple Chern number bands. We find analogs of quantum Hall ferromagnets in the menagerie of fractional Chern insulator phases. Unlike in the AlAs system, here the domain walls come naturally with gapped electronic excitations. We close with a result involving only topology: we show that ABC stacked multilayer graphene placed on boron nitride substrate has flat bands with non-zero local Berry curvature but zero Chern number. This allows access to an interaction dominated system with a non-trivial quantum distance metric but without the extra complication of a non-zero Chern number.

  15. Metallic Wall Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Goebel, Dan Michael (Inventor); Hofer, Richard Robert (Inventor); Mikellides, Ioannis G. (Inventor)

    2016-01-01

    A Hall thruster apparatus having walls constructed from a conductive material, such as graphite, and having magnetic shielding of the walls from the ionized plasma has been demonstrated to operate with nearly the same efficiency as a conventional non-magnetically shielded design using insulators as wall components. The new design is believed to provide the potential of higher power and uniform operation over the operating life of a thruster device.

  16. Hall effect magnetometer

    NASA Technical Reports Server (NTRS)

    Woollam, J. A.; Beale, H. A.; Spain, I. L. (Inventor)

    1974-01-01

    A magnetometer which uses a single crystal of bismuth selenide is described. The rhombohedral crystal structure of the sensing element is analyzed. The method of construction of the magnetometer is discussed. It is stated that the sensing crystal has a positive or negative Hall coefficient and a carrier concentration of about 10 to the 18th power to 10 to the 20th power per cubic centimeter.

  17. 27. THIRD FLOOR MAIN HALL FROM SIDE HALL LEADING TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. THIRD FLOOR MAIN HALL FROM SIDE HALL LEADING TO SERVICE STAIRS This hall is lit by three natural sources, the lightwell window of the main stairs visible in the distance, the skylight in the linen closet at the extreme left, and from the glazed openings in the interior and exterior doors of the nurse's room, out of sight to the right. - Woodrow Wilson House, 2340 South S Street, Northwest, Washington, District of Columbia, DC

  18. The characteristic of the building damage from historical large earthquakes in Kyoto

    NASA Astrophysics Data System (ADS)

    Nishiyama, Akihito

    2016-04-01

    The Kyoto city, which is located in the northern part of Kyoto basin in Japan, has a long history of >1,200 years since the city was initially constructed. The city has been a populated area with many buildings and the center of the politics, economy and culture in Japan for nearly 1,000 years. Some of these buildings are now subscribed as the world's cultural heritage. The Kyoto city has experienced six damaging large earthquakes during the historical period: i.e., in 976, 1185, 1449, 1596, 1662, and 1830. Among these, the last three earthquakes which caused severe damage in Kyoto occurred during the period in which the urban area had expanded. These earthquakes are considered to be inland earthquakes which occurred around the Kyoto basin. The damage distribution in Kyoto from historical large earthquakes is strongly controlled by ground condition and earthquakes resistance of buildings rather than distance from estimated source fault. Therefore, it is necessary to consider not only the strength of ground shaking but also the condition of building such as elapsed years since the construction or last repair in order to more accurately and reliably estimate seismic intensity distribution from historical earthquakes in Kyoto. The obtained seismic intensity map would be helpful for reducing and mitigating disaster from future large earthquakes.

  19. [Kyoto global consensus report for treatment of Helicobacter pylori and its implications for China].

    PubMed

    Xie, Chuan; Lyu, Nonghua

    2016-01-01

    Kyoto global consensus report on Helicobacter pylori gastritis (Gut, July 2015) is another important international consensus since the European Maastricht Ⅳ consensus was published. Kyoto consensus will improve the etiology-based classification, the diagnostic assessment of gastritis, and the treatment of H. pylori-associated dyspepsia and H. pylori gastritis. However, because of high rate of H. pylori infection and antibiotic resistance as well as limited health resources in China, we need to develop our own strategies of H. pylori infection control with the reference of the Kyoto global consensus.

  20. Thermal Hall Effect of Magnons

    NASA Astrophysics Data System (ADS)

    Murakami, Shuichi; Okamoto, Akihiro

    2017-01-01

    We review recent developments in theories and experiments on the magnon Hall effect. We derive the thermal Hall conductivity of magnons in terms of the Berry curvature of magnonic bands. In addition to the Dzyaloshinskii-Moriya interaction, we show that the dipolar interaction can make the Berry curvature nonzero. We mainly discuss theoretical aspects of the magnon Hall effect and related theoretical works. Experimental progress in this field is also mentioned.

  1. Multiscale Modeling of Hall Thrusters. Chapter 7: Plume Modeling

    DTIC Science & Technology

    2012-03-06

    NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON Justin W. Koo, Ph.D. a. REPORT Unclassified b. ABSTRACT Unclassified c. THIS PAGE...public release; distribution unlimited. 20 [28] J. Fife and M. Martinez -Sanchez, “Two-dimensional hybrid particle-in-cell (pic) modeling of hall thrusters...in 24th International Electric Propulsion Conference, Moscow, Russia, pp. 1213–1224, 1995. [29] F. Parra, E. Ahedo, J. Fife, and M. Martinez -Sanchez

  2. State-Tribal Relationships. A Report on the Indian Town Hall (8th, White Mountain Apache Reservation, Arizona, November 13-14, 1980).

    ERIC Educational Resources Information Center

    Arizona Commission of Indian Affairs, Phoenix.

    Proceedings from the 8th Indian Town Hall include conference activities of 22 representatives of American Indian tribes and the State of Arizona as they participated in the 2-day conference on state-tribal relationships. Eleven keynote speeches in full text are presented along with comments from seven tribal representatives on the conference and…

  3. Ion Velocity Distribution in a Low-Power Cylindrical Hall Thruster

    DTIC Science & Technology

    2010-07-01

    S. A. and Fisch , N. J., “Cylindrical Hall Thrusters,” Proceedings of the 37th AIAA Plasmadynamics and Lasers Conference, No. AIAA-2006-3245, American...Channel of Low-Power Hall Thruster,” IEEE Transactions on Plasma Science, Vol. 36, No. 5, October 2008, pp. 1989–1997. 4Raitses, Y., S. A. and Fisch , N. J... Fisch , N. J., “Enhanced Ionization in the Cylindrical Hall Thruster,” Journal of Applied Physics, Vol. 94, No. 2, 2003. 16Gildea, S. R., B. O. and

  4. Laser-Induced Fluorescence Velocity Measurements of a Low Power Cylindrical Hall Thruster

    DTIC Science & Technology

    2009-08-25

    Y., S. A. and Fisch , N. J., “Enhanced perfor- mance of cylindrical Hall thrusters,” Applied Physics Letters, Vol. 90, No. 221502, 2007. 3Hargus Jr., W...12Raitses, Y., S. A. and Fisch , N. J., “Cylindrical Hall Thrusters,” Proceedings of the 37th AIAA Plasmadynamics and Lasers Conference, No. AIAA-2006-3245...American Insti- tute of Aeronautics and Astronautics, June 2006. 13Smirnov, A., R. Y. and Fisch , N. J., “Enhanced Ion- ization in the Cylindrical Hall

  5. Magnesium Hall Thruster

    NASA Technical Reports Server (NTRS)

    Szabo, James J.

    2015-01-01

    This Phase II project is developing a magnesium (Mg) Hall effect thruster system that would open the door for in situ resource utilization (ISRU)-based solar system exploration. Magnesium is light and easy to ionize. For a Mars- Earth transfer, the propellant mass savings with respect to a xenon Hall effect thruster (HET) system are enormous. Magnesium also can be combusted in a rocket with carbon dioxide (CO2) or water (H2O), enabling a multimode propulsion system with propellant sharing and ISRU. In the near term, CO2 and H2O would be collected in situ on Mars or the moon. In the far term, Mg itself would be collected from Martian and lunar regolith. In Phase I, an integrated, medium-power (1- to 3-kW) Mg HET system was developed and tested. Controlled, steady operation at constant voltage and power was demonstrated. Preliminary measurements indicate a specific impulse (Isp) greater than 4,000 s was achieved at a discharge potential of 400 V. The feasibility of delivering fluidized Mg powder to a medium- or high-power thruster also was demonstrated. Phase II of the project evaluated the performance of an integrated, highpower Mg Hall thruster system in a relevant space environment. Researchers improved the medium power thruster system and characterized it in detail. Researchers also designed and built a high-power (8- to 20-kW) Mg HET. A fluidized powder feed system supporting the high-power thruster was built and delivered to Busek Company, Inc.

  6. Conference scene: DGVS spring conference 2009.

    PubMed

    Kolligs, Frank Thomas

    2009-10-01

    The 3rd annual DGVS Spring Conference of the German Society for Gastroenterology (Deutsche Gesellschaft für Verdauungs- und Stoffwechselkrankheiten) was held at the Seminaris Campus Hotel in Berlin, Germany, on 8-9 May, 2009. The conference was organized by Roland Schmid and Matthias Ebert from the Technical University of Munich, Germany. The central theme of the meeting was 'translational gastrointestinal oncology: towards personalized medicine and individualized therapy'. The conference covered talks on markers for diagnosis, screening and surveillance of colorectal cancer, targets for molecular therapy, response prediction in clinical oncology, development and integration of molecular imaging in gastrointestinal oncology and translational research in clinical trial design. Owing to the broad array of topics and limitations of space, this article will focus on biomarkers, response prediction and the integration of biomarkers into clinical trials. Presentations mentioned in this summary were given by Matthias Ebert (Technical University of Munich, Germany), Esmeralda Heiden (Epigenomics, Berlin, Germany), Frank Kolligs (University of Munich, Germany), Florian Lordick (University of Heidelberg, Germany), Hans Jorgen Nielsen (University of Copenhagen, Denmark), Anke Reinacher-Schick (University of Bochum, Germany), Christoph Röcken (University of Berlin, Germany), Wolff Schmiegel (University of Bochum, Germany) and Thomas Seufferlein (University of Halle, Germany).

  7. Influence of outdoor advertisement colors on psychological evaluation of townscape in Kyoto

    NASA Astrophysics Data System (ADS)

    Onishi, Ayumi; Ishida, Taiichiro; Katsuya, Yoshiko

    2002-06-01

    Outdoor advertisements must be one of the major factors that affect our psychological impression for townscapes. They often conflict with propr color environments in cities particularly in historic cities like Kyoto. In this study we investigated how outdoor advertisements influenced our visual evaluation of townscapes in Kyoto. In recent years, a new regulation for outdoor advertisements came into operation in Kyoto and some of the advertisements have been replaced or removed gradually. We examined psychological evaluation for the townscapes before and after their changes. In the experiment, subjects evaluated 'visual harmony,' 'visual busyness,' 'visual comfort' and 'suitability to Kyoto' of townscapes projected on a screen. The results indicated that the evaluation of 'visual busyness' significantly decreased with the amount of the advertisements. The relations between the advertisements and the psychological evaluation of the townscape are discussed.

  8. Global warming and environmental production efficiency ranking of the Kyoto Protocol nations.

    PubMed

    Feroz, Ehsan H; Raab, Raymond L; Ulleberg, Gerald T; Alsharif, Kamal

    2009-02-01

    This paper analyzes the United Nations Organization's Kyoto Protocol nations to address two questions. First, what are the environmental production efficiency rankings of these nations? Second, is there a relationship between a nation's ratification status and its environmental production efficiency ranking? Our findings suggest that the nations that have ratified the Kyoto Protocol are more likely to be environmentally production efficient as compared to the nations that have not ratified the Protocol.

  9. Chapin Hall Center for Children.

    ERIC Educational Resources Information Center

    Chicago Univ., IL. Chapin Hall Center for Children.

    This document consists of two separate publications: (1) "The Power of Knowing", a brief 12-page description of the Chapin Hall Center for Children, and (2) "Projects and Publications", a 67-page list of the center's projects and publications as of Autumn 1997. "The Power of Knowing" describes the Chapin Hall Center…

  10. Residence Hall Seating That Works.

    ERIC Educational Resources Information Center

    Wiens, Janet

    2003-01-01

    Describes the seating chosen for residence halls at the Massachusetts Institute of Technology and the University of New England. The seating required depends on ergonomics, aesthetics, durability, cost, and code requirements. In addition, residence halls must have a range of seating types to accommodate various uses. (SLD)

  11. Predictors of Residence Hall Involvement

    ERIC Educational Resources Information Center

    Arboleda, Ana; Wang, Yongyi; Shelley, Mack C., II; Whalen, Donald F.

    2003-01-01

    Residence hall students' (N = 1,186, 52% male, 90% White, 66% freshmen) involvement in their living community is influenced significantly by precollege student characteristics (gender, ethnicity), classification, attitudes (toward hall director, house cabinet, academic comfort, social environment, group study), and environmental variables (noise,…

  12. Rapid avoidance acquisition in Wistar-Kyoto rats.

    PubMed

    Servatius, R J; Jiao, X; Beck, K D; Pang, K C H; Minor, T R

    2008-10-10

    The relationship between trait stress-sensitivity, avoidance acquisition and perseveration of avoidance was examined using male Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats. Behavior in an open field was measured prior to escape/avoidance (E/A) acquisition and extinction. E/A was assessed in a discrete trial lever-press protocol. The signal-shock interval was 60s with subsequent shocks delivered every 3s until a lever-press occurred. A 3-min flashing light safety signal was delivered contingent upon a lever-press (or failure to respond in 5 min). WKY rats displayed phenotypic low open field activity, but were clearly superior to SD rats in E/A performance. As avoidance responses were acquired and reached asymptotic performance, SD rats exhibited "warm up", that is, SD rats rarely made avoidance responses on the initial trial of a session, even though later trials were consistently accompanied with avoidance responses. In contrast, WKY rats did not show the "warm up" pattern and avoided on nearly all trials of a session including the initial trial. In addition to the superior acquisition of E/A, WKY rats demonstrated several other avoidance features that were different from SD rats. Although the rates of nonreinforced intertrial responses (ITRs) were relatively low and selective to the early safety period, WKY displayed more ITRs than SD rats. With removal of the shocks extinction was delayed in WKY rats, likely reflecting their nearly perfect avoidance performance. Even after extensive extinction, first trial avoidance and ITRs were evident in WKY rats. Thus, WKY rats have a unique combination of trait behavioral inhibition (low open field activity and stress sensitivity) and superior avoidance acquisition and response perseveration making this strain a good model to understand anxiety disorders.

  13. NASA's Hall Thruster Program 2002

    NASA Technical Reports Server (NTRS)

    Jankovsky, Robert S.; Jacobson, David T.; Pinero, Luis R.; Manzella, David H.; Hofer, Richard R.; Peterson, Peter Y.

    2002-01-01

    The NASA Hall thruster program currently supports a number of tasks related to high power thruster development for a number of customers including the Energetics Program (formerly called the Space-based Program), the Space Solar Power Program, and the In-space Propulsion Program. In program year 2002, two tasks were central to the NASA Hall thruster program: 1) the development of a laboratory Hall thruster capable of providing high thrust at high power-, and 2) investigations into operation of Hall thrusters at high specific impulse. In addition to these two primary thruster development activities, there are a number of other on-going activities supported by the NASA Hall thruster program. These additional activities are related to issues such as high-power power processor architecture, thruster lifetime, and spacecraft integration.

  14. What Have Peace Education Commission Papers Dealt with in the 1990s? Comments on a Guide to Five Conference Reports. Reprints and Miniprints, No. 857.

    ERIC Educational Resources Information Center

    Bjerstedt, Ake

    Five international conferences were held during the 1990s by the Peace Education Commission, a semi-independent subgroup of the International Peace Research Association. The conferences were held in Groningen (The Netherlands), Firenze (Italy), Kyoto (Japan), Budapest (Hungary), and Valletta (Malta). This document is a brief commentary on the…

  15. Farm Hall: The Play

    NASA Astrophysics Data System (ADS)

    Cassidy, David C.

    2013-03-01

    It's July 1945. Germany is in defeat and the atomic bombs are on their way to Japan. Under the direction of Samuel Goudsmit, the Allies are holding some of the top German nuclear scientists-among them Heisenberg, Hahn, and Gerlach-captive in Farm Hall, an English country manor near Cambridge, England. As secret microphones record their conversations, the scientists are unaware of why they are being held or for how long. Thinking themselves far ahead of the Allies, how will they react to the news of the atomic bombs? How will these famous scientists explain to themselves and to the world their failure to achieve even a chain reaction? How will they come to terms with the horror of the Third Reich, their work for such a regime, and their behavior during that period? This one-act play is based upon the transcripts of their conversations as well as the author's historical work on the subject.

  16. Tuning giant anomalous Hall resistance ratio in perpendicular Hall balance

    SciTech Connect

    Zhang, J. Y.; Yang, G.; Wang, S. G. E-mail: ghyu@mater.ustb.edu.cn; Liu, J. L.; Wang, R. M.; Amsellem, E.; Kohn, A.; Yu, G. H. E-mail: ghyu@mater.ustb.edu.cn

    2015-04-13

    Anomalous Hall effect at room temperature in perpendicular Hall balance with a core structure of [Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4} has been tuned by functional CoO layers, where [Pt/Co]{sub 4} multilayers exhibit perpendicular magnetic anisotropy. A giant Hall resistance ratio up to 69 900% and saturation Hall resistance (R{sub S}{sup P}) up to 2590 mΩ were obtained in CoO/[Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4}/CoO system, which is 302% and 146% larger than that in the structure without CoO layers, respectively. Transmission electron microscopy shows highly textured [Co/Pt]{sub 4} multilayers and oxide layers with local epitaxial relations, indicating that the crystallographic structure has significant influence on spin dependent transport properties.

  17. Ward identities for Hall transport

    NASA Astrophysics Data System (ADS)

    Hoyos, Carlos; Kim, Bom Soo; Oz, Yaron

    2014-10-01

    We derive quantum field theory Ward identities based on linear area preserving and conformal transformations in 2+1 dimensions. The identities relate Hall viscosities, Hall conductivities and the angular momentum. They apply both for relativistic and non relativistic systems, at zero and at finite temperature. We consider systems with or without translation invariance, and introduce an external magnetic field and viscous drag terms. A special case of the identities yields the well known relation between the Hall conductivity and half the angular momentum density.

  18. Math/science education action conference report

    SciTech Connect

    Not Available

    1990-05-01

    On October 8--10, 1989, the US Department of Energy, the Lawrence Hall of Science, and the Lawrence Berkeley Laboratory sponsored a Math/Science Education Action Conference in Berkeley, California. The conference was co-chaired by Admiral James D. Watkins, Secretary of Energy, and Dr. Glenn T. Seaborg Chairman of the Lawrence Hall of Science. Nearly 250 scientists, educators, business executives, and government leaders came together to develop a concrete plan of action for restructuring and revitalizing mathematics and science education. Their target was to improve education for an entire cohort of children--the Class of 2007, the children born this school year--and their governing principle was one of collaboration, both between Federal agencies, and between public and private sectors. The report of the conference co-chairmen and participants is provided in this document. 41 figs.

  19. Multilayer thin film Hall effect device

    NASA Technical Reports Server (NTRS)

    Peters, Palmer N. (Inventor); Sisk, R. Charles (Inventor)

    1994-01-01

    A Hall effect device and a method of obtaining a magnetic field map of a magnetic body with the Hall effect device are presented. The device comprises: (1) a substrate, (2) a first layer having a first Hall coefficient deposited over the substrate, and (3) a second layer having a second Hall coefficient deposited over the first layer, the first and second layers cooperating to create, in the Hall effect device, a third Hall coefficient different from the first and second Hall coefficients. Creation of the third Hall coefficient by cooperation of the first and second layers allows use of materials for the first and second layers that were previously unavailable for Hall effect devices due to their relatively weak Hall coefficient.

  20. Antidepressants and REM sleep in Wistar-Kyoto and Sprague-Dawley rats.

    PubMed

    Ivarsson, Magnus; Paterson, Louise M; Hutson, Peter H

    2005-10-17

    Compared to other rat strains, the Wistar-Kyoto rats show increased amount of REM sleep, one of the characteristic sleep changes observed in depressed patients. The aims of this study were firstly to validate a simple sleep stage discriminator and then compare the effect of antidepressants on suppression of rapid eye movement (REM) sleep in Wistar-Kyoto rats and an outbred rat strain (Sprague-Dawley). Rats were implanted with telemetry transmitters with electroencephalogram/electromyogram electrodes. Following recovery, the animals were orally dosed at light onset with either desipramine (20 mg/kg), fluoxetine (10 mg/kg), citalopram (10 or 40 mg/kg) or vehicle in a cross-over design. Every 12-s epoch was automatically scored as WAKE, NREM or REM sleep. Results confirm that Wistar-Kyoto rats show increased amount of REM sleep and decreased REM latency compared with Sprague-Dawley rats. All antidepressants significantly suppressed REM sleep in Sprague-Dawley rats, but only the high dose of citalopram suppressed REM sleep in Wistar-Kyoto rats. These findings suggest that the enhanced REM activity in Wistar-Kyoto rats is less sensitive to the effect of antidepressants and therefore does not provide any additional predictive validity for assessing antidepressant efficacy.

  1. Optimization of Cylindrical Hall Thrusters

    SciTech Connect

    Yevgeny Raitses, Artem Smirnov, Erik Granstedt, and Nathaniel J. Fi

    2007-07-24

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation. __________________________________________________

  2. Optimization of Cylindrical Hall Thrusters

    SciTech Connect

    Yevgeny Raitses, Artem Smirnov, Erik Granstedt, and Nathaniel J. Fisch

    2007-11-27

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation.

  3. Not your grandfather's concert hall

    NASA Astrophysics Data System (ADS)

    Cooper, Russell; Malenka, Richard; Griffith, Charles; Friedlander, Steven

    2001-05-01

    The opening of Judy and Arthur Zankel Hall on 12 September 2003, restores Andrew Carnegie's original 1891 concept of having three outstanding auditoriums of different sizes under one roof, and creates a 21st-century venue for music performance and education. With concerts ranging from early music to avant-garde multimedia productions, from jazz to world music, and from solo recitals to chamber music, Zankel Hall expands the breadth and depth of Carnegie Hall's offerings. It allows for the integration of programming across three halls with minifestivals tailored both to the size and strengths of each hall and to the artists and music to be performed. The new flexible space also provides Carnegie Hall with an education center equipped with advanced communications technology. This paper discusses the unique program planned for this facility and how the architects, theatre consultants, and acousticians developed a design that fulfilled the client's expectations and coordinated the construction of the facility under the floor of the main Isaac Stern Auditorium without having to cancel a single performance.

  4. Not your grandfather's concert hall

    NASA Astrophysics Data System (ADS)

    Cooper, Russell; Malenka, Richard; Griffith, Charles; Friedlander, Steven

    2004-05-01

    The opening of Judy and Arthur Zankel Hall on 12 September 2003, restores Andrew Carnegie's original 1891 concept of having three outstanding auditoriums of different sizes under one roof, and creates a 21st-century venue for music performance and education. With concerts ranging from early music to avant-garde multimedia productions, from jazz to world music, and from solo recitals to chamber music, Zankel Hall expands the breadth and depth of Carnegie Hall's offerings. It allows for the integration of programming across three halls with minifestivals tailored both to the size and strengths of each hall and to the artists and music to be performed. The new flexible space also provides Carnegie Hall with an education center equipped with advanced communications technology. This paper discusses the unique program planned for this facility and how the architects, theatre consultants, and acousticians developed a design that fulfilled the client's expectations and coordinated the construction of the facility under the floor of the main Isaac Stern Auditorium without having to cancel a single performance.

  5. Carbon sinks and emissions trading under the Kyoto Protocol: a legal analysis.

    PubMed

    Bettelheim, Eric C; D'Origny, Gilonne

    2002-08-15

    The controversy over the issues of carbon sinks and emissions trading nearly aborted the Kyoto Protocol. The lengthy and intense debate over the roles that each are to play under the Protocol and the consequent political compromises has resulted in a complex set of provisions and an arcane nomenclature. The distinction drawn between the use of carbon sinks in developed countries under Joint Implementation and their use in developing countries under the Clean Development Mechanism (CDM) is a particular source of intricacy. It is at least arguable that key elements of the compromises reached at COP-6 and COP-7 in this regard are inconsistent with the terms of the Protocol and are ultra vires the Convention on Climate Change. This is a source of both uncertainty and potential legal challenge. Not only do the recent decisions create needless complexity, they also clearly discriminate against developing nations. Among the recent political compromises is the creation of a third type of non-bankable but tradeable unit with respect to forest management, which is only available to Annex I countries. The result is an anomalous one in which a variety of otherwise equivalent carbon credits can be generated under three different regimes including one, the CDM, that is subject to an elaborate regulatory overlay that discriminates against carbon sequestration by developing countries. For example, complying developed countries can essentially self-certify sequestration projects. In contrast, projects in developing countries must obtain prior approval from a subsidiary body, the CDM Executive Board, mandated to require detailed information and impose substantive and procedural hurdles not required or imposed by its companion body, the Article 6 Supervisory Committee on Joint Implementation Projects. The parallel and related debate over the third 'flexibility' mechanism, emissions trading, compounded the complexity of an already asymmetric and bifurcated system. The new requirements

  6. FOREWORD: The 7th Gravitational Wave Data Analysis Workshop, 17-19 December 2002, Kyoto, Japan

    NASA Astrophysics Data System (ADS)

    Kanda, Nobuyuki; Sasaki, Misao; Tagoshi, Hideyuki

    2003-09-01

    The 7th Gravitational Wave Data Analysis Workshop (GWDAW2002) was held at the International Institute for Advanced Studies (IIAS) in Kyoto, Japan, on 17-19 December 2002. The GWDAW series is one of the important international conferences supported by the Gravitational Wave International Committee (GWIC). The workshops have been held annually, and the topics covered range from data analyses for all kinds of gravitational wave detectors to theoretical issues on gravitational wave sources. This year's workshop consisted of seven categories of sessions: the status of detectors, space-based detectors, event search, detector characterization, coincidence of detectors and detector network analysis, new methods of analysis, and sources for advanced ground-based detectors. The year 2002 was an epoch-making year for gravitational wave detection experiments. Some of the large-scale ground-based laser interferometric detectors (LIGO, GEO and TAMA) entered their initial or developed stage of observation, performing scientific runs with durations of several weeks. As a result, many of the talks presented at the workshop were based on actual data taken from these experiments, and we were able to have more realistic discussions on gravitational wave detection. Furthermore, the successful operations of these laser interferometric detectors gave the gravitational wave community a strong motive to form a worldwide detector network, as practised by existing resonant-type detectors. In fact, there were reports on the simultaneous operation of five laser interferometric detectors, and a report on a plan for coincidence operations over a month. There were also reports on future space-based detectors and their source studies from aspects of the data analysis. Thanks to well-prepared talks and vivid discussions by the participants, the workshop was extremely fruitful. These proceedings contain refined and updated papers based on the talks given at the workshop and will provide readers of

  7. Four Members of the International Adult and Continuing Education Hall of Fame Reflect on Their Careers

    ERIC Educational Resources Information Center

    Sandmann, Lorilee R.; Miller, Gary E.

    2011-01-01

    Drawing on collective experience of over 200 years, four members of the International Adult and Continuing Education Hall of Fame were panelists in a session at the 2010 National Outreach Scholarship Conference. As the panelists reflected on careers in the field of adult and continuing education, four sustaining themes emerged: commitment,…

  8. PHOTOCOPY OF EARLY STEREO VIEW OF CARPENTERS' HALL. Date and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PHOTOCOPY OF EARLY STEREO VIEW OF CARPENTERS' HALL. Date and photographer unknown. Original in Carpenters' Hall - Carpenters' Company Hall, 320 Chestnut Street & Carpenters' Court, Philadelphia, Philadelphia County, PA

  9. Iodine Hall Thruster

    NASA Technical Reports Server (NTRS)

    Szabo, James

    2015-01-01

    Iodine enables dramatic mass and cost savings for lunar and Mars cargo missions, including Earth escape and near-Earth space maneuvers. The demonstrated throttling ability of iodine is important for a singular thruster that might be called upon to propel a spacecraft from Earth to Mars or Venus. The ability to throttle efficiently is even more important for missions beyond Mars. In the Phase I project, Busek Company, Inc., tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high-flow iodine feed system and supported by an existing Busek hollow cathode flowing xenon gas. The Phase I propellant feed system was evolved from a previously demonstrated laboratory feed system. Throttling of the thruster between 2 and 11 kW at 200 to 600 V was demonstrated. Testing showed that the efficiency of iodine fueled BHT-8000 is the same as with xenon, with iodine delivering a slightly higher thrust-to-power (T/P) ratio. In Phase II, a complete iodine-fueled system was developed, including the thruster, hollow cathode, and iodine propellant feed system. The nominal power of the Phase II system is 8 kW; however, it can be deeply throttled as well as clustered to much higher power levels. The technology also can be scaled to greater than 100 kW per thruster to support megawatt-class missions. The target thruster efficiency for the full-scale system is 65 percent at high specific impulse (Isp) (approximately 3,000 s) and 60 percent at high thrust (Isp approximately 2,000 s).

  10. PREFACE: Quark Matter 2006 Conference

    NASA Astrophysics Data System (ADS)

    Ma, Yu-Gang; Wang, En-Ke; Cai, Xu; Huang, Huan-Zhong; Wang, Xin-Nian; Zhu, Zhi-Yuan

    2007-07-01

    The Quark Matter 2006 conference was held on 14 20 November 2006 at the Shanghai Science Hall of the Shanghai Association of Sciences and Technology in Shanghai, China. It was the 19th International Conference on Ultra-Relativistic Nucleus Nucleus Collisions. The conference was organized jointly by SINAP (Shanghai Institute of Applied Physics, Chinese Academy of Sciences (CAS)) and CCNU (Central China Normal University, Wuhan). Over 600 scientists from 32 countries in five continents attended the conference. This is the first time that China has hosted such a premier conference in the field of relativistic heavy-ion collisions, an important event for the Chinese high energy nuclear physics community. About one half of the conference participants are junior scientists—a clear indication of the vigor and momentum for this field, in search of the fundamental nature of the nuclear matter at extreme conditions. Professor T D Lee, honorary chair of the conference and one of the founders of the quark matter research, delivered an opening address with his profound and philosophical remarks on the recent discovery of the nature of strongly-interacting quark-gluon-plasma (sQGP). Professor Hongjie Xu, director of SINAP, gave a welcome address to all participants on behalf of the two hosting institutions. Dr Peiwen Ji, deputy director of the Mathematics and Physics Division of the Natural Science Foundation of China (NSFC), also addressed the conference participants and congratulated them on the opening of the conference. Professor Mianheng Jiang, vice president of the Chinese Academy of Sciences (CAS), gave a concise introduction about the CAS as the premier research institution in China. He highlighted continued efforts at CAS to foster international collaborations between China and other nations. The Quark Matter 2006 conference is an example of such a successful collaboration between high energy nuclear physicists in China and other nations all over the world. The

  11. Acknowledgments - OOTR Annual Conference 2012 Proceedings.

    PubMed

    Toi, Masakazu

    2013-01-19

    It gives me great pleasure to announce the successful conclusion of the OOTR 8th Annual Conference, which was held on 20 and 21 April 2012 at the Westin Miyako Hotel, Kyoto, Japan. Since its last conference in Hong Kong in 2011, the Organisation for Oncology and Translational Research has continued to conduct a wide range of detailed clinical trials alongside hi-tech translational research, pushing on further than ever before in finding an optimal treatment strategy and a range of individualized treatment modalities for cancer patients. A great deal of valuable feedback from seasoned oncology professionals as well as newcomers to the field has been gratefully received and acted on by OOTR, helping us to continue our progress into cancer therapeutic research. Ever since the founding meeting in Hong Kong in 2004, OOTR has continued to learn and grow with the passing of each annual conference. Every conference has had a fundamental bearing on how we define treatment and guidelines regarding the latest scientific findings and methodologies toward improving cancer treatment and prevention. Based upon valuable lessons learned from the previous conferences, the OOTR 8th Annual Conference this time focused on cancer stem cells and cancer stroma. There were lectures on angiogenesis, predictive biomarkers for cancer therapy, prevention of oncological diseases, and hormone dependency and therapy. We held in-depth sessions in which we discussed the promotion of more appropriate therapeutic research and the advancement of more individualized treatments. The OOTR 8th Annual Conference proved to be an excellent opportunity for oncology professionals to participate in discussions, share experiences, meet like-minded professionals, and evaluate state-of-the-art hi-tech technologies. I extend my most heartfelt thanks to the contributing lecturers who traveled from all parts of the world to present their wonderful lectures at the seven key sessions: Session 1 - Hormone dependency and

  12. Hall thruster with grooved walls

    NASA Astrophysics Data System (ADS)

    Li, Hong; Ning, Zhongxi; Yu, Daren

    2013-02-01

    Axial-oriented and azimuthal-distributed grooves are formed on channel walls of a Hall thruster after the engine undergoes a long-term operation. Existing studies have demonstrated the relation between the grooves and the near-wall physics, such as sheath and electron near-wall transport. The idea to optimize the thruster performance with such grooves was also proposed. Therefore, this paper is devoted to explore the effects of wall grooves on the discharge characteristics of a Hall thruster. With experimental measurements, the variations on electron conductivity, ionization distribution, and integrated performance are obtained. The involved physical mechanisms are then analyzed and discussed. The findings help to not only better understand the working principle of Hall thruster discharge but also establish a physical fundamental for the subsequent optimization with artificial grooves.

  13. BRAIN ACONITASE ACTIVITY IN SPONTANEOUSLY HYPERTENSIVE (SHR) AND WISTAR-KYOTO (WKY) RATS.

    EPA Science Inventory

    Animal models of susceptibility are critical for human health risk assessment. Previous studies indicate that spontaneously hypertensive (SHR) rats are more sensitive than Wistar-Kyoto (WKY) rats to the cholinesterase (ChE) inhibitors such as carbaryl and chlorpyrifos. This diffe...

  14. Analysis of the Impacts of an Early Start for Compliance with the Kyoto Protocol

    EIA Publications

    1999-01-01

    This report describes the Energy Information Administration's analysis of the impacts of an early start, using the same methodology as in Impacts of the Kyoto Protocol on U.S. Energy Markets and Economic Activity, with only those changes in assumptions caused by the early start date.

  15. Museum as an integrated imaging device: visualization of ancient Kyoto cityscape from folding screen artifact

    NASA Astrophysics Data System (ADS)

    Miyata, Kimiyoshi; Oyabu, Umi; Kojima, Michihiro

    2012-03-01

    Museums hold cultural resources such as artworks, historical artifacts, and folklore materials. The National Museum of Japanese History holds over 200,000 of the cultural resources. A role of museum is to exhibit the cultural resources, therefore a museum could be referred to as a visualization device for the information society. In this research, visualization of a history image from cultural resources with interactive user interface will be mentioned. The material focused on is the oldest extant version of a genre of folding screen paintings that depict the thriving city of Kyoto in the four seasons, named Rekihaku's "Scenes In and Around Kyoto" designated as a nationally important cultural property in Japan. Over 1,400 people and a lot of residences, temples, and houses are drawn, and those are also information resource telling us about city scenes and people's life in Kyoto at that time. Historical researches were done by using a high resolution digital image obtained by a large scaled scanner, and scanned images are used for computer programs to visualize a history image of ancient Kyoto. Combinations between real materials and information provided by using the computer programs are also described in this research.

  16. Restructuring Residence Hall Programming: Residence Hall Educators with a Curriculum

    ERIC Educational Resources Information Center

    Buckner, Donald R.

    1977-01-01

    Development of residence hall learning environments through comprehensive educational programming has been inhibited by both the generalist nature of live-in professional staff positions and the retention of a student committee-centered programming philosophy. A rationale is developed in this article for a revised staffing pattern and a different…

  17. A Gift for Reading Hall No. 1

    ERIC Educational Resources Information Center

    MacWilliams, Bryon

    2009-01-01

    In this article, the author describes Reading Hall No. 1 of the Russian State Library. He was placed in the first reading hall in the mid-1990s, when the Russian government still honored Soviet traditions of granting certain privileges to certain foreigners. In the first hall, the rules are different. He can request as many books as he wants. He…

  18. Berry curvature and various thermal Hall effects

    NASA Astrophysics Data System (ADS)

    Zhang, Lifa

    2016-10-01

    Applying the approach of semiclassical wave packet dynamics, we study various thermal Hall effects where carriers can be electron, phonon, magnon, etc. A general formula of thermal Hall conductivity is obtained to provide an essential physics for various thermal Hall effects, where the Berry phase effect manifests naturally. All the formulas of electron thermal Hall effect, phonon Hall effect, and magnon Hall effect can be directly reproduced from the general formula. It is also found that the Strěda formula can not be directly applied to the thermal Hall effects, where only the edge magnetization contributes to the Hall effects. Furthermore, we obtain a combined formula for anomalous Hall conductivity, thermal Hall electronic conductivity and thermal Hall conductivity for electron systems, where the Berry curvature is weighted by a different function. Finally, we discuss particle magnetization and its relation to angular momentum of the carrier, change of which could induce a mechanical rotation; and possible experiments for thermal Hall effect associated with a mechanical rotation are also proposed.

  19. The Other Hall Effect: College Board Physics

    ERIC Educational Resources Information Center

    Sheppard, Keith; Gunning, Amanda M.

    2013-01-01

    Edwin Herbert Hall (1855-1938), discoverer of the Hall effect, was one of the first winners of the AAPT Oersted Medal for his contributions to the teaching of physics. While Hall's role in establishing laboratory work in high schools is widely acknowledged, his position as chair of the physics section of the Committee on College Entrance…

  20. Overview of Hall D Complex

    SciTech Connect

    Chudakov, Eugene A.

    2016-04-01

    Hall D is a new experimental hall at Jefferson Lab, designed for experiments with a photon beam. The primary motivation for Hall D is the GlueX experiment [1,2], dedicated to meson spectroscopy. The Hall D complex consists of: An electron beam line used to extract the 5.5-pass electrons from the accelerator into the Tagger Hall. The designed beam energy is E e = 12 GeV;The Tagger Hall, where the electron beam passes through a thin radiator (~0.01% R.L.) and is deflected into the beam dump. The electrons that lost >30% of their energy in the radiator are detected with scintillator hodoscopes providing a ~0.1% energy resolution for the tagged photons. Aligned diamond radiators allow to produce linearly polarized photons via the Coherent Bremsstrahlung. The beam dump is limited to 60 kW (5 µA at 12 GeV); The Collimator Cave contains a collimator for the photon beam and dipole magnets downstream in order to remove charged particles. The 3.4 mm diameter collimator, located about 75 m downstream of the radiator, selects the central cone of the photon beam increasing its average linear polarization, up to ~40%in the coherent peak at 9 GeV; Hall D contains several elements of the photon beam line, and themain spectrometer. A Pair Spectrometer consists of a thin converter, a dipole magnet, and a two-arm detector used to measure the energy spectrum of the photon beam. The main spectrometer is based on a 2-T superconducting solenoid, 4 m long and 1.85 m bore diameter. The liquid hydrogen target is located in the front part the solenoid. The charged tracks are detected with a set of drift chambers; photons are detected with two electromagnetic calorimeters. There are also scintillator hodoscopes for triggering and time-of-flight measurements. The spectrometer is nearly hermetic in an angular range of 1° < θ < 120 •. The momentum resolution is σ p /p ~ 1 ₋ ₋3% depending on the polar angle θ. The energy resolution of the electromagnetic calorimeters is

  1. Planar Hall effect bridge magnetic field sensors

    SciTech Connect

    Henriksen, A. D.; Dalslet, B. T.; Skieller, D. H.; Lee, K. H.; Okkels, F.; Hansen, M. F.

    2010-07-05

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar Hall effect bridge sensors.

  2. Conference Resolution

    NASA Astrophysics Data System (ADS)

    2009-04-01

    Since the first IUPAP International Conference on Women in Physics (Paris, March 2002) and the Second Conference (Rio de Janeiro, May 2005), progress has continued in most countries and world regions to attract girls to physics and advance women into leadership roles, and many working groups have formed. The Third Conference (Seoul, October 2008), with 283 attendees from 57 countries, was dedicated to celebrating the physics achievements of women throughout the world, networking toward new international collaborations, building each participant's capacity for career success, and aiding the formation of active regional working groups to advance women in physics. Despite the progress, women remain a small minority of the physics community in most countries.

  3. Optical Hall effect-model description: tutorial.

    PubMed

    Schubert, Mathias; Kühne, Philipp; Darakchieva, Vanya; Hofmann, Tino

    2016-08-01

    The optical Hall effect is a physical phenomenon that describes the occurrence of magnetic-field-induced dielectric displacement at optical wavelengths, transverse and longitudinal to the incident electric field, and analogous to the static electrical Hall effect. The electrical Hall effect and certain cases of the optical Hall effect observations can be explained by extensions of the classic Drude model for the transport of electrons in metals. The optical Hall effect is most useful for characterization of electrical properties in semiconductors. Among many advantages, while the optical Hall effect dispenses with the need of electrical contacts, electrical material properties such as effective mass and mobility parameters, including their anisotropy as well as carrier type and density, can be determined from the optical Hall effect. Measurement of the optical Hall effect can be performed within the concept of generalized ellipsometry at an oblique angle of incidence. In this paper, we review and discuss physical model equations, which can be used to calculate the optical Hall effect in single- and multiple-layered structures of semiconductor materials. We define the optical Hall effect dielectric function tensor, demonstrate diagonalization approaches, and show requirements for the optical Hall effect tensor from energy conservation. We discuss both continuum and quantum approaches, and we provide a brief description of the generalized ellipsometry concept, the Mueller matrix calculus, and a 4×4 matrix algebra to calculate data accessible by experiment. In a follow-up paper, we will discuss strategies and approaches for experimental data acquisition and analysis.

  4. Electron dynamics in Hall thruster

    NASA Astrophysics Data System (ADS)

    Marini, Samuel; Pakter, Renato

    2015-11-01

    Hall thrusters are plasma engines those use an electromagnetic fields combination to confine electrons, generate and accelerate ions. Widely used by aerospace industries those thrusters stand out for its simple geometry, high specific impulse and low demand for electric power. Propulsion generated by those systems is due to acceleration of ions produced in an acceleration channel. The ions are generated by collision of electrons with propellant gas atoms. In this context, we can realize how important is characterizing the electronic dynamics. Using Hamiltonian formalism, we derive the electron motion equation in a simplified electromagnetic fields configuration observed in hall thrusters. We found conditions those must be satisfied by electromagnetic fields to have electronic confinement in acceleration channel. We present configurations of electromagnetic fields those maximize propellant gas ionization and thus make propulsion more efficient. This work was supported by CNPq.

  5. Hall sensors for extreme temperatures.

    PubMed

    Jankowski, Jakub; El-Ahmar, Semir; Oszwaldowski, Maciej

    2011-01-01

    We report on the preparation of the first complete extreme temperature Hall sensor. This means that the extreme-temperature magnetic sensitive semiconductor structure is built-in an extreme-temperature package especially designed for that purpose. The working temperature range of the sensor extends from -270 °C to +300 °C. The extreme-temperature Hall-sensor active element is a heavily n-doped InSb layer epitaxially grown on GaAs. The magnetic sensitivity of the sensor is ca. 100 mV/T and its temperature coefficient is less than 0.04 %/K. This sensor may find applications in the car, aircraft, spacecraft, military and oil and gas industries.

  6. Considering WTO law in the design of climate change regimes beyond Kyoto

    NASA Astrophysics Data System (ADS)

    Gaines, Sanford E.

    2009-11-01

    This article describes the most important provisions of World Trade Organization (WTO) agreements that should be considered in designing laws and regulations under likely post-Kyoto climate change mitigation regimes. The Kyoto Protocol and the expected post-Kyoto international climate agreement depend on national measures to implement market-based mitigation measures. This market strategy promotes international exchanges of goods, investments, and services such as cross-border trading of credits for emissions reductions and transnational financing for projects that avoid emissions through the Clean Development Mechanism. Moreover, the United States and other countries, concerned over "leakage" of greenhouse gas (GHG) emissions through relocation of industry to other countries coupled with political worry over manufacturing competitiveness, have proposed national climate legislation containing border adjustments on imported goods or implicit subsidies for national producers, raising additional WTO considerations. The article assesses the likely effectiveness of such trade-related measures in achieving climate change mitigation goals and the potential trade policy infringements and trade distortions that they might bring about. Alternative strategies for achieving GHG mitigation goals in closer conformity with WTO law and policy will be suggested.

  7. The fluctuation induced Hall effect

    SciTech Connect

    Shen, W.; Prager, S.C.

    1993-02-01

    The fluctuation induced Hall term, {le}{approximately}{ovr J} {times} {approximately}{ovr B}{ge}, has been measured in the MST reversed field pinch. The term is of interest as a possible source of current self-generation (dynamo). It is found to be non-negligible, but small in that it can account for less than 25% of the dynamo driven current.

  8. The fluctuation induced Hall effect

    SciTech Connect

    Shen, W.; Prager, S.C.

    1993-02-01

    The fluctuation induced Hall term, [le][approximately][ovr J] [times] [approximately][ovr B][ge], has been measured in the MST reversed field pinch. The term is of interest as a possible source of current self-generation (dynamo). It is found to be non-negligible, but small in that it can account for less than 25% of the dynamo driven current.

  9. Ionization oscillations in Hall accelerators

    NASA Astrophysics Data System (ADS)

    Barral, S.; Peradzyński, Z.

    2010-01-01

    The underlying mechanism of low-frequency oscillations in Hall accelerators is investigated theoretically. It is shown that relaxation oscillations arise from a competition between avalanche ionization and the advective transport of the working gas. The model derived recovers the slow progression and fast recession of the ionization front. Analytical approximations of the shape of current pulses and of the oscillation frequency are provided for the case of large amplitude oscillations.

  10. Fractional quantum Hall effect revisited

    NASA Astrophysics Data System (ADS)

    Jacak, J.; Łydżba, P.; Jacak, L.

    2015-10-01

    The topology-based explanation of the fractional quantum Hall effect (FQHE) is summarized. The cyclotron braid subgroups crucial for this approach are introduced in order to identify the origin of the Laughlin correlations in 2D (two-dimensional) Hall systems. Flux-tubes and vortices for composite fermions in their standard constructions are explained in terms of cyclotron braids. The derivation of the hierarchy of the FQHE is proposed by mapping onto the integer effect within the topology-based approach. The experimental observations of the FQHE supporting the cyclotron braid picture are reviewed with a special attention paid to recent experiments with a suspended graphene. The triggering role of a carrier mobility for organization of the fractional state in Hall configuration is emphasized. The prerequisites for the FQHE are indicated including topological conditions substantially increasing the previously accepted set of physical necessities. The explanation of numerical studies by exact diagonalizations of the fractional Chern insulator states is formulated in terms of the topology condition applied to the Berry field flux quantization. Some new ideas withz regard to the synthetic fractional states in the optical lattices are also formulated.

  11. Remote Sensing and the Kyoto Protocol: A Review of Available and Future Technology for Monitoring Treaty Compliance

    NASA Technical Reports Server (NTRS)

    Imhoff, Marc L.; Rosenquist, A.; Milne, A. K.; Dobson, M. C.; Qi, J.

    2000-01-01

    An International workshop was held to address how remote sensing technology could be used to support the environmental monitoring requirements of the Kyoto Protocol. An overview of the issues addressed and the findings of the workshop are discussed.

  12. Prototype Space Technology Hall of Fame exhibit at Technology 2003: Analysis of data from computer-based questionaire

    NASA Technical Reports Server (NTRS)

    Ewell, Robert N.

    1994-01-01

    The U.S. Space Foundation displayed its prototype Space Technology Hall of Fame exhibit design at the Technology 2003 conference in Anaheim, CA, December 7-9, 1993. In order to sample public opinion on space technology in general and the exhibit in particular, a computer-based survey was set up as a part of the display. The data collected was analyzed.

  13. Solving the Acoustic Problem in Polyvalent Hall at Mauritius: Global Design Challenge Facing Larsen and Toubro, Limited

    ERIC Educational Resources Information Center

    Sankar, Chetan S.; Raju, P. K.; Alur, Ramachandriah; Venkateswaran, Rajan; Elangovan, Rajasekar

    2011-01-01

    The architect for the Mauritius Auditorium project sat in his office at Larsen & Toubro's headquarters in Chennai, India, pondering the phone call he had just received from the vice president, Mr. K.P. Raghavan. The polyvalent hall of the conference center was about to be used to host its first rock concert in February 2005, but during a…

  14. Fort Hall air emissions study, Fort Hall Indian Reservation, Fort Hall, Idaho

    SciTech Connect

    Metcalf, S.W.; Sonnenfeld, N.L.; Rolka, D.L.; Kaye, W.E.

    1995-11-01

    The Agency for Toxic Substances and Disease Registry (ATSDR) conducted a cross-sectional health study at the Fort Hall Indian Reservation in Idaho to investigate concerns about the health effects on reservation residents that might be attributed to two phosphate-processing plants located near the reservation`s southern border. In addition to increased particulates, air emissions from these plants included phosphorus pentoxide, cadmium, chromium, fluoride, uranium, and its daughter radionuclides. A total of 515 participants -- 229 from Fort Hall and 286 from a comparison group at the Duck Valley Indian Reservation -- were interviewed in person by trained American Indian interviewers. Approximately 100 residents of each reservation performed pulmonary function tests and provided urine specimens that were analyzed for cadmium, chromium, fluoride, and several renal biomarkers.

  15. Observation of the Zero Hall Plateau in a Quantum Anomalous Hall Insulator.

    PubMed

    Feng, Yang; Feng, Xiao; Ou, Yunbo; Wang, Jing; Liu, Chang; Zhang, Liguo; Zhao, Dongyang; Jiang, Gaoyuan; Zhang, Shou-Cheng; He, Ke; Ma, Xucun; Xue, Qi-Kun; Wang, Yayu

    2015-09-18

    We report experimental investigations on the quantum phase transition between the two opposite Hall plateaus of a quantum anomalous Hall insulator. We observe a well-defined plateau with zero Hall conductivity over a range of magnetic field around coercivity when the magnetization reverses. The features of the zero Hall plateau are shown to be closely related to that of the quantum anomalous Hall effect, but its temperature evolution exhibits a significant difference from the network model for a conventional quantum Hall plateau transition. We propose that the chiral edge states residing at the magnetic domain boundaries, which are unique to a quantum anomalous Hall insulator, are responsible for the novel features of the zero Hall plateau.

  16. Demonstration of Laser-Induced Fluorescence on Krypton Hall Effect Thruster

    DTIC Science & Technology

    2011-08-10

    Conference Paper 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Demonstration of Laser-Induced Fluorescence on Krypton Hall Effect...Sep 2011. 14. ABSTRACT There is growing interest within the electrostatic propulsion community for the use of krypton as a propellant. It is a...probe thruster krypton propellant acceleration with the minimum disturbance to the overall propellant stream similar to those already developed for

  17. A Performance Comparison of Xenon and Krypton Propellant on an SPT-100 Hall Thruster (Preprint)

    DTIC Science & Technology

    2011-08-10

    Conference Paper 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER A Performance Comparison of Xenon and Krypton Propellant on an SPT...Wiesbaden, Germany, 11-15 Sep 2011. 14. ABSTRACT The use of krypton as an alternative to xenon for Hall thruster propellant is an interesting...plume data from electrostatic probes. This paper presents the results of performance measurements made using an inverted pendulum thrust stand. Krypton

  18. DEVELOPMENT OF IMPROVED HALL EFFECT SENSORS.

    DTIC Science & Technology

    HALL EFFECT , MAGNETOMETERS, GAIN, SENSITIVITY, MAGNETIC FIELDS, DETECTION, ELECTROMAGNETIC PROBES, WEIGHT, VOLUME, BATTERY COMPONENTS, INDIUM ALLOYS, ANTIMONY ALLOYS, FERRITES, MANPORTABLE EQUIPMENT.

  19. AN A. C. HALL EFFECT GAUSSMETER,

    DTIC Science & Technology

    MEASURING INSTRUMENTS, MEASURING INSTRUMENTS, HALL EFFECT , MAGNETOMETERS, MEASUREMENT, GENERATORS, CIRCUITS, ALTERNATING CURRENT, GERMANIUM, SEMICONDUCTOR DIODES, GALVANOMETERS, VOLTAGE, DIRECT CURRENT, MAGNETIC FIELDS.

  20. Listening to the acoustics in concert halls

    NASA Astrophysics Data System (ADS)

    Beranek, Leo L.; Griesinger, David

    2001-05-01

    How does acoustics affect the symphonic music performed in a concert hall? The lecture begins with an illustrated discussion of the architectural features that influence the acoustics. Boston Symphony Hall, which was built in 1900 when only one facet of architectural design was known, now rates as one of the world's great halls. How this occurred will be presented. Music is composed with some acoustical environment in mind and this varies with time from the Baroque to the Romantic to the Modern musical period. Conductors vary their interpretation according to the hall they are in. Well-traveled listeners and music critics have favorite halls. The lecture then presents a list of 58 halls rank ordered according to their acoustical quality based on interviews of music critics and conductors. Modern acoustical measurements made in these halls are compared with their rankings. Music recordings will be presented that demonstrate how halls sound that have different measured acoustical parameters. Photographs of a number of recently built halls are shown as examples of how these known acoustical factors have been incorporated into architectural design.

  1. Hall Thruster Technology for NASA Science Missions

    NASA Technical Reports Server (NTRS)

    Manzella, David; Oh, David; Aadland, Randall

    2005-01-01

    The performance of a prototype Hall thruster designed for Discovery-class NASA science mission applications was evaluated at input powers ranging from 0.2 to 2.9 kilowatts. These data were used to construct a throttle profile for a projected Hall thruster system based on this prototype thruster. The suitability of such a Hall thruster system to perform robotic exploration missions was evaluated through the analysis of a near Earth asteroid sample return mission. This analysis demonstrated that a propulsion system based on the prototype Hall thruster offers mission benefits compared to a propulsion system based on an existing ion thruster.

  2. Listening to the acoustics in concert halls

    NASA Astrophysics Data System (ADS)

    Beranek, Leo L.; Griesinger, David

    2004-05-01

    How does acoustics affect the symphonic music performed in a concert hall? The lecture begins with an illustrated discussion of the architectural features that influence the acoustics. Boston Symphony Hall, which was built in 1900 when only one facet of architectural design was known, now rates as one of the world's great halls. How this occurred will be presented. Music is composed with some acoustical environment in mind and this varies with time from the Baroque to the Romantic to the Modern musical period. Conductors vary their interpretation according to the hall they are in. Well-traveled listeners and music critics have favorite halls. The lecture then presents a list of 58 halls rank ordered according to their acoustical quality based on interviews of music critics and conductors. Modern acoustical measurements made in these halls are compared with their rankings. Music recordings will be presented that demonstrate how halls sound that have different measured acoustical parameters. Photographs of a number of recently built halls are shown as examples of how these known acoustical factors have been incorporated into architectural design.

  3. Hall-effect arc protector

    DOEpatents

    Rankin, Richard A.; Kotter, Dale K.

    1997-01-01

    The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.

  4. Hall-effect arc protector

    DOEpatents

    Rankin, R.A.; Kotter, D.K.

    1997-05-13

    The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored. 2 figs.

  5. Town Hall with Secretary Moniz

    SciTech Connect

    Energy Secretary Ernest Moniz; Deputy Secretary of Energy Daniel Poneman

    2013-07-18

    In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about his plans for a reorganization of the Energy Department’s management structure. The plans will help better achieve the Department’s key priorities and those of the President, including implementing the President’s Climate Action Plan, “all of the above” energy strategy and nuclear security agenda. After his remarks, Moniz, joined by Deputy Secretary Dan Poneman, took questions from the audience in the Forrestal Auditorium as well as email questions from other Department locations.

  6. Temperature Gradient in Hall Thrusters

    SciTech Connect

    D. Staack; Y. Raitses; N.J. Fisch

    2003-11-24

    Plasma potentials and electron temperatures were deduced from emissive and cold floating probe measurements in a 2 kW Hall thruster, operated in the discharge voltage range of 200-400 V. An almost linear dependence of the electron temperature on the plasma potential was observed in the acceleration region of the thruster both inside and outside the thruster. This result calls into question whether secondary electron emission from the ceramic channel walls plays a significant role in electron energy balance. The proportionality factor between the axial electron temperature gradient and the electric field is significantly smaller than might be expected by models employing Ohmic heating of electrons.

  7. Temperature Stable Hall Effect Sensors

    NASA Astrophysics Data System (ADS)

    Partin, D. L.; Heremans, J. P.; Schroeder, T.; Thrush, C. M.; Flores, L. A.

    2004-03-01

    Magnetic field sensors are needed for high accuracy position, angle, force, strain, torque, and current flow measurements. Molecular beam epitaxy was used to grow tellurium-doped indium gallium antimonide thin films. Hall effect sensors made from these films have been studied for their magnetic sensitivity and thermal stability. For a range of alloy composition and n-type doping levels, high magnetic sensitivity from -40°C to +200°C was found with a resolution of better than +/- 0.5 percent over the entire temperature range.

  8. Electron Transport in Hall Thrusters

    NASA Astrophysics Data System (ADS)

    McDonald, Michael Sean

    Despite high technological maturity and a long flight heritage, computer models of Hall thrusters remain dependent on empirical inputs and a large part of thruster development to date has been heavily experimental in nature. This empirical approach will become increasingly unsustainable as new high-power thrusters tax existing ground test facilities and more exotic thruster designs stretch and strain the boundaries of existing design experience. The fundamental obstacle preventing predictive modeling of Hall thruster plasma properties and channel erosion is the lack of a first-principles description of electron transport across the strong magnetic fields between the cathode and anode. In spite of an abundance of proposed transport mechanisms, accurate assessments of the magnitude of electron current due to any one mechanism are scarce, and comparative studies of their relative influence on a single thruster platform simply do not exist. Lacking a clear idea of what mechanism(s) are primarily responsible for transport, it is understandably difficult for the electric propulsion scientist to focus his or her theoretical and computational tools on the right targets. This work presents a primarily experimental investigation of collisional and turbulent Hall thruster electron transport mechanisms. High-speed imaging of the thruster discharge channel at tens of thousands of frames per second reveals omnipresent rotating regions of elevated light emission, identified with a rotating spoke instability. This turbulent instability has been shown through construction of an azimuthally segmented anode to drive significant cross-field electron current in the discharge channel, and suggestive evidence points to its spatial extent into the thruster near-field plume as well. Electron trajectory simulations in experimentally measured thruster electromagnetic fields indicate that binary collisional transport mechanisms are not significant in the thruster plume, and experiments

  9. Town Hall with Secretary Moniz

    ScienceCinema

    Energy Secretary Ernest Moniz; Deputy Secretary of Energy Daniel Poneman

    2016-07-12

    In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about his plans for a reorganization of the Energy Department’s management structure. The plans will help better achieve the Department’s key priorities and those of the President, including implementing the President’s Climate Action Plan, “all of the above” energy strategy and nuclear security agenda. After his remarks, Moniz, joined by Deputy Secretary Dan Poneman, took questions from the audience in the Forrestal Auditorium as well as email questions from other Department locations.

  10. Conference Space

    ERIC Educational Resources Information Center

    Tillett, Wade

    2016-01-01

    The following is an exploration of the spatial configurations (and their implications) within a typical panel session at an academic conference. The presenter initially takes up different roles and hyperbolically describes some possible messages that the spatial arrangement sends. Eventually, the presenter engages the audience members in atypical…

  11. PHOTOCOPY OF EARLY STEREO VIEW OF INTERIOR OF CARPENTERS' HALL. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PHOTOCOPY OF EARLY STEREO VIEW OF INTERIOR OF CARPENTERS' HALL. Date and photographer unknown. Original in Carpenters' Hall - Carpenters' Company Hall, 320 Chestnut Street & Carpenters' Court, Philadelphia, Philadelphia County, PA

  12. Use of virtual slide system for quick frozen intra-operative telepathology diagnosis in Kyoto, Japan.

    PubMed

    Tsuchihashi, Yasunari; Takamatsu, Terumasa; Hashimoto, Yukimasa; Takashima, Tooru; Nakano, Kooji; Fujita, Setsuya

    2008-07-15

    We started to use virtual slide (VS) and virtual microscopy (VM) systems for quick frozen intra-operative telepathology diagnosis in Kyoto, Japan. In the system we used a digital slide scanner, VASSALO by CLARO Inc., and a broadband optic fibre provided by NTT West Japan Inc. with the best effort capacity of 100 Mbps. The client is the pathology laboratory of Yamashiro Public Hospital, one of the local centre hospitals located in the south of Kyoto Prefecture, where a full-time pathologist is not present. The client is connected by VPN to the telepathology centre of our institute located in central Kyoto. As a result of the recent 15 test cases of VS telepathology diagnosis, including cases judging negative or positive surgical margins, we could estimate the usefulness of VS in intra-operative remote diagnosis. The time required for the frozen section VS file making was found to be around 10 min when we use x10 objective and if the maximal dimension of the frozen sample is less than 20 mm. Good correct focus of VS images was attained in all cases and all the fields of each tissue specimen. Up to now the capacity of best effort B-band appears to be sufficient to attain diagnosis on time in intra-operation. Telepathology diagnosis was achieved within 5 minutes in most cases using VS viewer provided by CLARO Inc. The VS telepathology system was found to be superior to the conventional still image telepathology system using a robotic microscope since in the former we can observe much greater image information than in the latter in a certain limited time of intra-operation and in the much more efficient ways. In the near future VS telepathology will replace conventional still image telepathology with a robotic microscope even in quick frozen intra-operative diagnosis.

  13. Shortened Conditioned Eyeblink Response Latency in Male but not Female Wistar-Kyoto Hyperactive Rats

    PubMed Central

    Thanellou, Alexandra; Schachinger, Kira M.; Green, John T.

    2014-01-01

    Reductions in the volume of the cerebellum and impairments in cerebellar-dependent eyeblink conditioning have been observed in attention-deficit/hyperactivity disorder (ADHD). Recently, it was reported that subjects with ADHD as well as male spontaneously hypertensive rats (SHR), a strain that is frequently employed as an animal model in the study of ADHD, exhibit a parallel pattern of timing deficits in eyeblink conditioning. One criticism that has been posed regarding the validity of the SHR strain as an animal model for the study of ADHD is that SHRs are not only hyperactive but also hypertensive. It is conceivable that many of the behavioral characteristics seen in SHRs that seem to parallel the behavioral symptoms of ADHD are not solely due to hyperactivity but instead are the net outcome of the interaction between hyperactivity and hypertension. We used Wistar-Kyoto Hyperactive (WKHA) and Wistar-Kyoto Hypertensive (WKHT) rats (males and females), strains generated from recombinant inbreeding of SHRs and their progenitor strain, Wistar-Kyoto (WKY) rats, to compare eyeblink conditioning in strains that are exclusively hyperactive or hypertensive. We used a long-delay eyeblink conditioning task in which a tone conditioned stimulus was paired with a periorbital stimulation unconditioned stimulus (750-ms delay paradigm). Our results showed that WKHA and WKHT rats exhibited similar rates of conditioned response (CR) acquisition. However, WKHA males displayed shortened CR latencies (early onset and peak latency) in comparison to WKHT males. In contrast, female WKHAs and WKHTs did not differ. In subsequent extinction training, WKHA rats extinguished at similar rates in comparison to WKHT rats. The current results support the hypothesis of a relationship between cerebellar abnormalities and ADHD in an animal model of ADHD-like symptoms that does not also exhibit hypertension, and suggest that cerebellar-related timing deficits are specific to males. PMID:19485572

  14. [Climatic change and public health: scenarios after the coming into force of the Kyoto Protocol].

    PubMed

    Ballester, Ferran; Díaz, Julio; Moreno, José Manuel

    2006-03-01

    According to the reports of the intergovernmental panel for climatic change (IPCC) human beings of the present and near future are going to experiment, in fact we are already experimenting, important changes in the world climate. Conscious of the magnitude of the problem, international organizations have taken a series of initiatives headed to stop the climatic change and to reduce its impact. This willingness has been shaped into the agreements established in the Kyoto protocol, where countries commit to reduce greenhouse-effect gas emissions. Kyoto protocol has come into force on February 16th 2005 with the support of 141 signing countries. Among the major worries are the effects which climatic change may have upon health, such as: 1) changes in the morbidity- mortality related to temperature; 2) Effects on health related with extreme meteorological events (tornados, storms, hurricanes and extreme raining); 3) Air pollution and increase of associated health effects; d) Diseases transmitted by food and water and 4) Infectious diseases transmitted by vectors and by rodents. Even if all the countries in the world committed to the Kyoto Protocol, some consequences of the climatic change will be inevitable; among them some will have a negative impact on health. It would be necessary to adapt a key response strategy to minimize the impacts of climatic change and to reduce, at minimum cost, its adverse effects on health. From the Public Health position, a relevant role can and must be played concerning the understanding of the risks for health of such climatic changes, the design of surveillance systems to evaluate possible impacts, and the establishment of systems to prevent or reduce damages as well as the identification and development of investigation needs.

  15. Anaerobic digestion of organic waste in Japan: the first demonstration plant at Kyoto City.

    PubMed

    Komatsu, T; Kimura, T; Kuriyama, Y; Isshiki, Y; Kawano, T; Hirao, T; Masuda, M; Yokoyama, K; Matsumoto, T; Takeda, M

    2002-01-01

    Recycling of Municipal Solid Waste is vigorously promoted in Japan and the necessity of energy recovery from organic waste is increasing. An anaerobic digestion demonstration plant for organic waste in Kyoto City, Japan has been operated for about two years. Three kinds of wastes (garbage and leftovers from hotels, yard waste and used paper) mixed at various ratios are used. The plant has maintained stable operations with each mixture, generating biogas by the decomposition of VS at the rate of about 820 m3N/ton-VS.

  16. High contrast neutron radiography with optical devices in Kyoto University reactor

    NASA Astrophysics Data System (ADS)

    Kawabata, Y.; Nakano, T.; Hino, M.; Sunohara, H.; Matsushima, U.; Takenaka, N.

    2004-08-01

    The high-contrast neutron radiography has been performed at a VCN guide (VCN) and a supermirror cold neutron guide (CN-3) in Kyoto University Reactor. The large absorption cross-section of very low-energy neutrons can show a slight change of sample which thermal neutrons can not show. The effectiveness is shown in the fields of botany, agriculture and industrial researches. A new spectrum change option using high Qc supermirror ( m=4) is attached. It can change the upper limit of the energy of exposure neutrons by reflections, and gives a high flexibility of the experimental condition.

  17. Technical Digest of Papers Presented at the UK National Quantum Electronics Conference (11th) Held in Belfast, Northern Ireland on 30 August - 2 September 1993

    DTIC Science & Technology

    1993-09-02

    Entertainment - Registration City Hall Hall Common Room 0 0 0 0 0 0 0 0 0 ( CONFERENCE PROGRAMME MONDAY 30 AUGUST 1993 0 0845 WELCOME INVITED 1...semiconductor laser diode (LD) or edge-emitting ligh , emitting diode (LED) is directly related to the active region carrier density (n). The LD gain

  18. Training Top 10 Hall of Fame

    ERIC Educational Resources Information Center

    Training, 2012

    2012-01-01

    Microsoft Corporation and SCC Soft Computer are the newest inductees into the Training Top 10 Hall of Fame, joining the ranks of the 11 companies named to the hall since its inception in 2008 (Wyeth Pharmaceuticals subsequently was acquired by Pfizer Inc. in 2009). These 11 companies held Top 10 spots in the Training Top 50, Top 100, and now Top…

  19. Hall devices improve electric motor efficiency

    NASA Technical Reports Server (NTRS)

    Haeussermann, W.

    1979-01-01

    Efficiency of electric motors and generators is reduced by radial magnetic forces created by symmetric fields within device. Forces are sensed and counteracted by Hall devices on excitation or control windings. Hall generators directly measure and provide compensating control of anu asymmetry, eliminating additional measurements needed for calibration feedback control loop.

  20. Quantum Hall effect in quantum electrodynamics

    SciTech Connect

    Penin, Alexander A.

    2009-03-15

    We consider the quantum Hall effect in quantum electrodynamics and find a deviation from the quantum-mechanical prediction for the Hall conductivity due to radiative antiscreening of electric charge in an external magnetic field. A weak dependence of the universal von Klitzing constant on the magnetic field strength, which can possibly be observed in a dedicated experiment, is predicted.

  1. Azimuthal Spoke Propagation in Hall Effect Thrusters

    DTIC Science & Technology

    2013-08-01

    Approved for public release; distribution unlimited. IEPC-2013- Background Pressure Effects on Krypton Hall Effect Thruster Internal Acceleration...Why are we doing this work? – Continued examination of alternative Hall effect thruster propellants: Krypton – Interest in effects of test...Distribution unlimited 2 Photograph of BHT-600 operating on krypton Long exposure photograph of BHT-600 operating on krypton showing extended plume

  2. 20th Annual Residence Hall Construction Report

    ERIC Educational Resources Information Center

    Agron, Joe

    2009-01-01

    Even in difficult economic times, colleges and universities continue to invest in residence hall construction projects as a way to attract new students and keep existing ones on campus. According to data from "American School & University"'s 20th annual Residence Hall Construction Report, the median new project completed in 2008 was…

  3. 19th Annual Residence Hall Construction Report

    ERIC Educational Resources Information Center

    Agron, Joe

    2008-01-01

    The construction of residence hall facilities at colleges and universities continues to be strong, as institutions scramble to meet the housing needs and varied demands of a growing student population. This article presents data collected from 39 new residence hall projects completed in 2007. According to American School & University's 19th…

  4. View of north front and west sides of hall, facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of north front and west sides of hall, facing south - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

  5. Interior detail of dispatch boards in main hall, facing west ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior detail of dispatch boards in main hall, facing west - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

  6. Hall magneto-hydrodynamics in protoplanetary discs

    NASA Astrophysics Data System (ADS)

    Béthune, W.; Lesur, G.; Ferreira, J.

    2016-12-01

    Protoplanetary discs exhibit large-scale, organised structures. Because they are dense and cold, they should be weakly ionized, and hence concerned by non-ideal plasma effects, such as the Hall effect. We perform numerical simulations of non-stratified Keplerian discs, in the non-ideal magnetohydrodynamic framework. We show that the Hall effect causes self-organisation through three distinct stages. A weak Hall effect enhances turbulent transport. At intermediate strength, it produces magnetized vortices. A strong Hall effect generates axisymmetric zonal flows. These structures may trap dust particles, and thus influence planetary formation. The transport of angular momentum is quenched in the organised state, impugning the relevance of magneto-rotational turbulence as a driving mechanism of accretion in Hall dominated regions.

  7. Flexible Hall sensors based on graphene.

    PubMed

    Wang, Zhenxing; Shaygan, Mehrdad; Otto, Martin; Schall, Daniel; Neumaier, Daniel

    2016-04-14

    The excellent electronic and mechanical properties of graphene provide a perfect basis for high performance flexible electronic and sensor devices. Here, we present the fabrication and characterization of flexible graphene based Hall sensors. The Hall sensors are fabricated on 50 μm thick flexible Kapton foil using large scale graphene grown by chemical vapor deposition technique on copper foil. Voltage and current normalized sensitivities of up to 0.096 V VT(-1) and 79 V AT(-1) were measured, respectively. These values are comparable to the sensitivity of rigid silicon based Hall sensors and are the highest values reported so far for any flexible Hall sensor devices. The sensitivity of the Hall sensor shows no degradation after being bent to a minimum radius of 4 mm, which corresponds to a tensile strain of 0.6%, and after 1000 bending cycles to a radius of 5 mm.

  8. Flexible Hall sensors based on graphene

    NASA Astrophysics Data System (ADS)

    Wang, Zhenxing; Shaygan, Mehrdad; Otto, Martin; Schall, Daniel; Neumaier, Daniel

    2016-03-01

    The excellent electronic and mechanical properties of graphene provide a perfect basis for high performance flexible electronic and sensor devices. Here, we present the fabrication and characterization of flexible graphene based Hall sensors. The Hall sensors are fabricated on 50 μm thick flexible Kapton foil using large scale graphene grown by chemical vapor deposition technique on copper foil. Voltage and current normalized sensitivities of up to 0.096 V VT-1 and 79 V AT-1 were measured, respectively. These values are comparable to the sensitivity of rigid silicon based Hall sensors and are the highest values reported so far for any flexible Hall sensor devices. The sensitivity of the Hall sensor shows no degradation after being bent to a minimum radius of 4 mm, which corresponds to a tensile strain of 0.6%, and after 1000 bending cycles to a radius of 5 mm.

  9. (Fourth international conference on fusion reactor materials)

    SciTech Connect

    Bloom, E.E.

    1990-01-24

    This report summarizes the International Conference on Fusion Reactor Materials (ICFRM-4) which was held December 4--9, 1989, in Kyoto, Japan, as well as the results of several workshops, planning meetings, and laboratory visits made by the travelers. The ICFRM-4 is the major forum to present and exchange information on materials research and development in support of the world's fusion development efforts. About 360 papers were presented by the 347 conference attendees. Highlights of the conference are presented. A proposal by the United States to host ICFRM-5 was accepted by the International Advisory Committee. ORNL will be the host laboratory. A meeting of the DOE/JAERI Annex I Steering Committee to review the US/Japan Collaborative Testing of First Wall and Blanket Structural Materials with Mixed Spectrum Fission Reactors was held at JAERI Headquarters on December 1. The Japanese emphasized the critical importance of a resumption of HFIR operation. Even though the HFIR outage has lasted three plus years this program has continued to provide new and important data on materials behavior which has particular relevance to ITER.

  10. Cerebellar Structure and Function in Male Wistar-Kyoto Hyperactive Rats

    PubMed Central

    Thanellou, Alexandra; Green, John T.

    2014-01-01

    Previous research has suggested that the Wistar-Kyoto Hyperactive (WKHA) rat strain may model some of the behavioral features associated with attention-deficit/hyperactivity disorder (ADHD). We have shown that, in cerebellar-dependent eyeblink conditioning, WKHA emit eyeblink CRs with shortened onset latencies. To further characterize the shortened CR onset latencies seen in WKHA rats, we examined 750-ms delay conditioning with either a tone CS or a light CS, we extended acquisition training, and we included Wistar rats as an additional, outbred control strain. Our results indicated that WKHAs learned more quickly and showed a shortened CR onset latency to a tone CS compared to both Wistar-Kyoto Hypertensive (WKHT) and Wistars. WKHAs and Wistars show a lengthening of CR onset latency over conditioning with a tone CS and an increasing confinement of CRs to the later part of the tone CS (inhibition of delay). WKHAs learned more quickly to a light CS only in comparison to WKHTs and showed a shortened CR onset latency only in comparison to Wistars. Wistars showed an increasing confinement of CRs to the late part of the light CS over conditioning. We used unbiased stereology to estimate the number of Purkinje and granule cells in the cerebellar cortex of the three strains. Our results indicated that WKHAs have more granule cells than Wistars and WKHTs and more Purkinje cells than Wistars. Results are discussed in terms of CS processing and cerebellar cortical contributions to EBC. PMID:23398437

  11. Detection of rickettsial DNA in ticks and wild boars in Kyoto City, Japan.

    PubMed

    Someya, Azusa; Ito, Ryuki; Maeda, Akihiko; Ikenaga, Mitsuhiro

    2015-01-01

    The tick is a well-known vector for arthropod-borne pathogens, such as tick-borne encephalitis, Lyme disease, Japanese spotted fever and severe fever with thrombocytopenia syndrome. It is therefore important to know the tick population and distribution in our environment and wild animals in order to prevent tick-borne diseases. Here, we report the results of tick surveillance from May to September 2011 at 14 geographical points and in 5 wild boars in Kyoto City, Kyoto prefecture, Japan. We collected 3,198 ticks comprising 5 tick species, Haemaphysalis (H.) longicornis, H. flava, H. kitaokai, Amblyomma testudinarium and Dermacentor taiwanensis. Interestingly, the proportion of tick species varied according to geographical region within the city. The ticks collected in the city were reported as potential vectors of pathogens, such as rickettsiosis. We detected rickettsial DNA by PCR in 71.1% of 201 ticks investigated. The ticks that carried rickettsiae were distributed across the whole the city. The sequences of PCR-amplified DNA fragments were determined and showed similarities to spotted fever group rickettsiae. Although their pathogenicity for animals including humans is still unclear, it is important to stay alert and pay attention to tick-borne diseases in order to ensure the safety of the citizens of the city as well as that of visitors.

  12. Cerebellar structure and function in male Wistar-Kyoto hyperactive rats.

    PubMed

    Thanellou, Alexandra; Green, John T

    2013-04-01

    Previous research has suggested that the Wistar-Kyoto Hyperactive (WKHA) rat strain may model some of the behavioral features associated with attention-deficit/hyperactivity disorder (ADHD). We have shown that, in cerebellar-dependent eyeblink conditioning, male WKHAs emit eyeblink CRs with shortened onset latencies. To further characterize the shortened CR onset latencies seen in male WKHA rats, we examined 750-ms delay conditioning with either a tone conditional stimulus (CS) or a light CS, we extended acquisition training, and we included Wistar rats as an additional, outbred control strain. Our results indicated that WKHAs learned more quickly and showed a shortened CR onset latency to a tone CS compared to both Wistar-Kyoto Hypertensive (WKHT) and Wistars. WKHAs and Wistars show a lengthening of CR onset latency over conditioning with a tone CS and an increasing confinement of CRs to the later part of the tone CS (inhibition of delay). WKHAs learned more quickly to a light CS only in comparison to WKHTs, and showed a shortened CR onset latency only in comparison to Wistars. Wistars showed an increasing confinement of CRs to the late part of the light CS over conditioning. We used unbiased stereology to estimate the number of Purkinje and granule cells in the cerebellar cortex of the three strains. Our results indicated that WKHAs have more granule cells than Wistars and WKHTs and more Purkinje cells than Wistars. Results are discussed in terms of CS processing and cerebellar cortical contributions to EBC.

  13. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ON RHIC SPIN PHYSICS III AND IV, POLARIZED PARTONS AT HIGH Q2 REGION, AUGUST 3, 2000 AT BNL, OCTOBER 14, 2000 AT KYOTO UNIVERSITY.

    SciTech Connect

    BUNCE, G.; VIGDOR, S.

    2001-03-15

    International workshop on II Polarized Partons at High Q2 region 11 was held at the Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, Japan on October 13-14, 2000, as a satellite of the international conference ''SPIN 2000'' (Osaka, Japan, October 16-21,2000). This workshop was supported by RIKEN (The Institute of Physical and Chemical Research) and by Yukawa Institute. The scientific program was focused on the upcoming polarized collider RHIC. The workshop was also an annual meeting of RHIC Spin Collaboration (RSC). The number of participants was 55, including 28 foreign visitors and 8 foreign-resident Japanese participants, reflecting the international nature of the RHIC spin program. At the workshop there were 25 oral presentations in four sessions, (1) RHIC Spin Commissioning, (2) Polarized Partons, Present and Future, (3) New Ideas on Polarization Phenomena, (4) Strategy for the Coming Spin Running. In (1) the successful polarized proton commissioning and the readiness of the accelerator for the physics program impressed us. In (2) and (3) active discussions were made on the new structure function to be firstly measured at RHIC, and several new theoretical ideas were presented. In session (4) we have established a plan for the beam time requirement toward the first collision of polarized protons. These proceedings include the transparencies presented at the workshop. The discussion on ''Strategy for the Coming Spin Running'' was summarized by the chairman of the session, S. Vigdor and G. Bunce.

  14. The quantum Hall effect helicity

    SciTech Connect

    Shrivastava, Keshav N.

    2015-04-16

    The quantum Hall effect in semiconductor heterostructures is explained by two signs in the angular momentum j=l±s and g=(2j+1)/(2l+1) along with the Landau factor (n+1/2). These modifications in the existing theories explain all of the fractional charges. The helicity which is the sign of the product of the linear momentum with the spin p.s plays an important role for the understanding of the data at high magnetic fields. In particular it is found that particles with positive sign in the spin move in one direction and those with negative sign move in another direction which explains the up and down stream motion of the particles.

  15. Hall conductance in graphene with point defects.

    PubMed

    İslamoğlu, S; Oktel, M Ö; Gülseren, O

    2013-02-06

    We investigate the Hall conductance of graphene with point defects within the Kubo formalism, which allows us to calculate the Hall conductance without constraining the Fermi energy to lie in a gap. For pure graphene, which we model using a tight-binding Hamiltonian, we recover both the usual and the anomalous integer quantum Hall effects depending on the proximity to the Dirac points. We investigate the effect of point defects on Hall conduction by considering a dilute but regular array of point defects incorporated into the graphene lattice. We extend our calculations to include next nearest neighbor hopping, which breaks the bipartite symmetry of the lattice. We find that impurity atoms which are weakly coupled to the rest of the lattice result in gradual disappearance of the high conductance value plateaus. For such impurities, especially for vacancies which are decoupled from the lattice, strong modification of the Hall conductance occurs near the E = 0 eV line, as impurity states are highly localized. In contrast, if the impurities are strongly coupled, they create additional Hall conductance plateaus at the extremum values of the spectrum, signifying separate impurity bands. Hall conductance values within the original spectrum are not strongly modified.

  16. Direct Drive for Low Power Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.

    2005-01-01

    Due to recent studies, NASA has initiated the development of a low power Hall thruster for discovery class missions. The potential advantages of a low power Hall thruster is primarily due to its high efficiency operation at low power and its lower complexity compared to ion engines. Direct drive is another method of reducing the complexity of a Hall thruster system while improving its efficiency. The technical challenges associated with this technology are reported. Additionally, the benefits of this technology are discussed based on parametric studies and mission analysis.

  17. Joule heating in spin Hall geometry

    NASA Astrophysics Data System (ADS)

    Taniguchi, Tomohiro

    2016-07-01

    The theoretical formula for the entropy production rate in the presence of spin current is derived using the spin-dependent transport equation and thermodynamics. This theory is applicable regardless of the source of the spin current, for example, an electric field, a temperature gradient, or the Hall effect. It reproduces the result in a previous work on the dissipation formula when the relaxation time approximation is applied to the spin relaxation rate. By using the developed theory, it is found that the dissipation in the spin Hall geometry has a contribution proportional to the square of the spin Hall angle.

  18. The quantum Hall effects: Philosophical approach

    NASA Astrophysics Data System (ADS)

    Lederer, P.

    2015-05-01

    The Quantum Hall Effects offer a rich variety of theoretical and experimental advances. They provide interesting insights on such topics as gauge invariance, strong interactions in Condensed Matter physics, emergence of new paradigms. This paper focuses on some related philosophical questions. Various brands of positivism or agnosticism are confronted with the physics of the Quantum Hall Effects. Hacking's views on Scientific Realism, Chalmers' on Non-Figurative Realism are discussed. It is argued that the difficulties with those versions of realism may be resolved within a dialectical materialist approach. The latter is argued to provide a rational approach to the phenomena, theory and ontology of the Quantum Hall Effects.

  19. Chiral Thermoelectrics with Quantum Hall Edge States

    NASA Astrophysics Data System (ADS)

    Sánchez, Rafael; Sothmann, Björn; Jordan, Andrew N.

    2015-04-01

    The thermoelectric properties of a three-terminal quantum Hall conductor are investigated. We identify a contribution to the thermoelectric response that relies on the chirality of the carrier motion rather than on spatial asymmetries. The Onsager matrix becomes maximally asymmetric with configurations where either the Seebeck or the Peltier coefficients are zero while the other one remains finite. Reversing the magnetic field direction exchanges these effects, which originate from the chiral nature of the quantum Hall edge states. The possibility to generate spin-polarized currents in quantum spin Hall samples is discussed.

  20. Piezo Voltage Controlled Planar Hall Effect Devices.

    PubMed

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-22

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  1. Piezo Voltage Controlled Planar Hall Effect Devices

    NASA Astrophysics Data System (ADS)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K. W.; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  2. Submicrometer hall sensors for superparamagnetic nanoparticle detection.

    SciTech Connect

    Mihajlovic, G.; Xiong, P.; von Molnar, S.; Field, M.; Sullivan, G. J.; Ohtani, K.; Ohno, H.; Materials Science Division; Florida State Univ.; Teledyne Scientific Co. LLC

    2007-06-01

    Submicrometer Hall sensors, with Hall cross width of {approx}250 nm, were fabricated from InAs/AlSb quantum well semiconductor heterostructures. The room-temperature device characteristics were examined by experimental Hall effect and electronic noise measurements combined with analytical calculations. The noise-equivalent magnetic moment resolution of the order of 104muB/radicHz was obtained at frequencies above {approx}1 kHz. We show that the devices can achieve single superparamagnetic nanoparticle detection and thus be employed in experiments involving single magnetically labeled biomolecule detection.

  3. Chiral thermoelectrics with quantum Hall edge states.

    PubMed

    Sánchez, Rafael; Sothmann, Björn; Jordan, Andrew N

    2015-04-10

    The thermoelectric properties of a three-terminal quantum Hall conductor are investigated. We identify a contribution to the thermoelectric response that relies on the chirality of the carrier motion rather than on spatial asymmetries. The Onsager matrix becomes maximally asymmetric with configurations where either the Seebeck or the Peltier coefficients are zero while the other one remains finite. Reversing the magnetic field direction exchanges these effects, which originate from the chiral nature of the quantum Hall edge states. The possibility to generate spin-polarized currents in quantum spin Hall samples is discussed.

  4. Integer Quantum Hall Effect in Trilayer Graphene

    NASA Astrophysics Data System (ADS)

    Kumar, A.; Escoffier, W.; Poumirol, J. M.; Faugeras, C.; Arovas, D. P.; Fogler, M. M.; Guinea, F.; Roche, S.; Goiran, M.; Raquet, B.

    2011-09-01

    By using high-magnetic fields (up to 60 T), we observe compelling evidence of the integer quantum Hall effect in trilayer graphene. The magnetotransport fingerprints are similar to those of the graphene monolayer, except for the absence of a plateau at a filling factor of ν=2. At a very low filling factor, the Hall resistance vanishes due to the presence of mixed electron and hole carriers induced by disorder. The measured Hall resistivity plateaus are well reproduced theoretically, using a self-consistent Hartree calculations of the Landau levels and assuming an ABC stacking order of the three layers.

  5. Conferences revisited

    NASA Astrophysics Data System (ADS)

    Radcliffe, Jonathan

    2008-08-01

    Way back in the mid-1990s, as a young PhD student, I wrote a Lateral Thoughts article about my first experience of an academic conference (Physics World 1994 October p80). It was a peach of a trip - most of the lab decamped to Grenoble for a week of great weather, beautiful scenery and, of course, the physics. A whole new community was there for me to see in action, and the internationality of it all helped us to forget about England's non-appearance in the 1994 World Cup finals.

  6. Observation of the magnon Hall effect.

    PubMed

    Onose, Y; Ideue, T; Katsura, H; Shiomi, Y; Nagaosa, N; Tokura, Y

    2010-07-16

    The Hall effect usually occurs in conductors when the Lorentz force acts on a charge current in the presence of a perpendicular magnetic field. Neutral quasi-particles such as phonons and spins can, however, carry heat current and potentially exhibit the thermal Hall effect without resorting to the Lorentz force. We report experimental evidence for the anomalous thermal Hall effect caused by spin excitations (magnons) in an insulating ferromagnet with a pyrochlore lattice structure. Our theoretical analysis indicates that the propagation of the spin waves is influenced by the Dzyaloshinskii-Moriya spin-orbit interaction, which plays the role of the vector potential, much as in the intrinsic anomalous Hall effect in metallic ferromagnets.

  7. Hall Opens Doors to Astronaut Heroes

    NASA Video Gallery

    Space shuttle astronauts Bonnie Dunbar, Curt Brown and Eileen Collins joined an elite group of American space heroes as they were inducted into the U.S. Astronaut Hall of Fame on April 20, during a...

  8. Quantum Hall effect in momentum space

    NASA Astrophysics Data System (ADS)

    Ozawa, Tomoki; Price, Hannah M.; Carusotto, Iacopo

    2016-05-01

    We theoretically discuss a momentum-space analog of the quantum Hall effect, which could be observed in topologically nontrivial lattice models subject to an external harmonic trapping potential. In our proposal, the Niu-Thouless-Wu formulation of the quantum Hall effect on a torus is realized in the toroidally shaped Brillouin zone. In this analogy, the position of the trap center in real space controls the magnetic fluxes that are inserted through the holes of the torus in momentum space. We illustrate the momentum-space quantum Hall effect with the noninteracting trapped Harper-Hofstadter model, for which we numerically demonstrate how this effect manifests itself in experimental observables. Extension to the interacting trapped Harper-Hofstadter model is also briefly considered. We finally discuss possible experimental platforms where our proposal for the momentum-space quantum Hall effect could be realized.

  9. Hall effect degradation of rail gun performance

    NASA Astrophysics Data System (ADS)

    Witalis, E. A.; Gunnarsson, Patrik

    1993-01-01

    The paper discusses the Hall effect and shows it to be significant in the low-density and high-field trailing part of a plasma armature. Without the Hall effect a simple armature model is derived. It exhibits properties expected from classical MHD theory and shows that the purely relativistic electric charge buildup on the rails is a fundamental gun property, leading to V(breech) = 1.5 V(muzzle). The mathematics involved in accounting for Hall effect phenomena is described. These are of two types: the Hall-skewing of the armature current and the superimposed plasma flow rotation. For decreasing gun current the two effects efficiently combine to eject armature plasma rearwards, thus creating conditions for arc separation and parasitic arcs.

  10. Success of Hall technique crowns questioned.

    PubMed

    Nainar, S M Hashim

    2012-01-01

    Hall technique is a method of providing stainless steel crowns for primary molars without tooth preparation and requires no local anesthesia. Literature review showed inconclusive evidence and therefore this technique should not be used in clinical practice.

  11. 75 FR 433 - Notice of Intent to Repatriate a Cultural Item: Seton Hall University Museum, Seton Hall...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ... Cultural Item: Seton Hall University Museum, Seton Hall University, South Orange, NJ AGENCY: National Park... possession of the Seton Hall University Museum, Seton Hall University, South Orange, NJ, that meets the... University Museum purchased it from Mr. Tarrant in 1962 or 1963. Written evidence of Haudenosaunee...

  12. Economic Impacts of the Kyoto Protocol. Hearing before the Committee on Energy and Natural Resources, United States Senate, One Hundred Sixth Congress, First Session, March 25, 1999

    SciTech Connect

    1999-11-01

    This hearing focuses on the economic impact of the Kyoto Protocol to the Framework Convention on Climate Change. In the Kyoto Protocol, which was completed in December 1997, the administration agreed to legally binding obligations to reduce US greenhouse gas emissions to seven percent below 1990 levels during the years 2008--2011. This climate treaty does not subject developing countries to emission targets.

  13. Design study of multi-imaging plate system for BNCT irradiation field at Kyoto university reactor.

    PubMed

    Tanaka, Kenichi; Sakurai, Yoshinori; Kajimoto, Tsuyoshi; Tanaka, Hiroki; Takata, Takushi; Endo, Satoru

    2016-09-01

    The converter configuration for a multi-imaging plate system was investigated for the application of quality assurance in the irradiation field profile for boron neutron capture therapy. This was performed by the simulation calculation using the PHITS code in the fields at the Heavy Water Neutron Irradiation Facility of Kyoto University Reactor. The converter constituents investigated were carbon for gamma rays, and polyethylene with and without LiF at varied (6)Li concentration for thermal, epithermal, and fast neutrons. Consequently, potential combinations of the converters were found for two components, gamma rays and thermal neutrons, for the standard thermal neutron mode and three components of gamma rays, epithermal neutrons, and thermal or fast neutrons, for the standard mixed or epithermal neutron modes, respectively.

  14. [Climate change and Kyoto Protocol. Science and strategies. Obligations for Spain].

    PubMed

    de Castro González, Federico Velázquez

    2005-01-01

    This article presents climate change as the major environmental problem of our time. A result of the so-called "greenhouse effect", climate change is caused by certain gases, the concentrations in the atmosphere of which are growing exponentially. The consequences of these gases are going to be felt throughout the entire biosphere, from weather phenomenon to humans, creating a uncertain panorama which is going to be requiring some fast-paced adaptation on the part of all species. This is not, however, an irreversible process, taking action thus being possible and necessary, by combining education and lawmaking measures brought into being within the timeframes and to the extents set forth under the 1997 Kyoto Protocol. Spain will be one of the most highly-affected countries, and its strategy may therefore mean a highly-valuable tool for correcting the deviations caused and contributing to the urgent control of global emissions.

  15. Development of a mono-energetic positron beam line at the Kyoto University Research Reactor

    NASA Astrophysics Data System (ADS)

    Sato, K.; Xu, Q.; Yoshiie, T.; Sano, T.; Kawabe, H.; Nagai, Y.; Nagumo, K.; Inoue, K.; Toyama, T.; Oshima, N.; Kinomura, A.; Shirai, Y.

    2015-01-01

    Positron beam facilities are widely used for solid state physics and material science studies. A positron beam facility has been constructed at the Kyoto University Research Reactor (KUR) in order to expand its application range. The KUR is a light-water-moderated tank-type reactor operated at a rated thermal power of 5 MW. A positron beam has been transported successfully from the reactor to the irradiation chamber. The total moderated positron rate was greater than 1.4 × 106/s while the reactor operated at a reduced power of 1 MW. Special attention was paid for the design of the in-pile position source to prevent possible damage of the reactor in case of severe earthquakes.

  16. The Hall effect in star formation

    NASA Astrophysics Data System (ADS)

    Braiding, C. R.; Wardle, M.

    2012-05-01

    Magnetic fields play an important role in star formation by regulating the removal of angular momentum from collapsing molecular cloud cores. Hall diffusion is known to be important to the magnetic field behaviour at many of the intermediate densities and field strengths encountered during the gravitational collapse of molecular cloud cores into protostars, and yet its role in the star formation process is not well studied. We present a semianalytic self-similar model of the collapse of rotating isothermal molecular cloud cores with both Hall and ambipolar diffusion, and similarity solutions that demonstrate the profound influence of the Hall effect on the dynamics of collapse. The solutions show that the size and sign of the Hall parameter can change the size of the protostellar disc by up to an order of magnitude and the protostellar accretion rate by 50 per cent when the ratio of the Hall to ambipolar diffusivities is varied between -0.5 ≤ηH/ηA≤ 0.2. These changes depend upon the orientation of the magnetic field with respect to the axis of rotation and create a preferred handedness to the solutions that could be observed in protostellar cores using next-generation instruments such as ALMA. Hall diffusion also determines the strength and position of the shocks that bound the pseudo and rotationally supported discs, and can introduce subshocks that further slow accretion on to the protostar. In cores that are not initially rotating (not examined here), Hall diffusion can even induce rotation, which could give rise to disc formation and resolve the magnetic braking catastrophe. The Hall effect clearly influences the dynamics of gravitational collapse and its role in controlling the magnetic braking and radial diffusion of the field merits further exploration in numerical simulations of star formation.

  17. A post-Kyoto partner: Considering the Montreal Protocol as a tool to manage nitrous oxide

    NASA Astrophysics Data System (ADS)

    Mauzerall, D. L.; Kanter, D.; Ravishankara, A. R.; Daniel, J. S.; Portmann, R. W.; Grabiel, P.; Moomaw, W.; Galloway, J. N.

    2012-12-01

    While nitrous oxide (N2O) was recently identified as the largest remaining anthropogenic threat to the stratospheric ozone layer, it is currently regulated under the 1997 Kyoto Protocol due to its simultaneous ability to warm the climate. The threat N2O poses to the stratospheric ozone layer, coupled with the uncertain future of the international climate regime, motivates our exploration of issues that could be relevant to the Parties to the 1987 Montreal Protocol if they decide to take measures to manage N2O in the future. There are clear legal avenues for the Montreal Protocol and its parent treaty, the 1985 Vienna Convention, to regulate N2O, as well as several ways to share authority with the existing and future international climate treaties. N2O mitigation strategies exist to address its most significant anthropogenic sources, including agriculture, where behavioral practices and new technologies could contribute significantly to mitigation efforts. Existing policies managing N2O and other forms of reactive nitrogen could be harnessed and built upon by the Montreal Protocol's existing bodies to implement N2O controls. Given the tight coupling of the nitrogen cycle, such controls would likely simultaneously reduce emissions of reactive nitrogen and hence have co-benefits for ecosystems and public health. Nevertheless, there are at least three major regulatory challenges that are unique and central to N2O control: food security, equity, and the nitrogen cascade. The possible inclusion of N2O in the Montreal Protocol need not be viewed as a sign of the Kyoto Protocol's failure to adequately deal with climate change, given the complexity of the issue. Rather, it could represent an additional tool in the field of sustainable development diplomacy.lt;img border=0 src="images/B43K-06_B.jpg">

  18. Star Formation and the Hall Effect

    NASA Astrophysics Data System (ADS)

    Braiding, Catherine

    2011-10-01

    Magnetic fields play an important role in star formation by regulating the removal of angular momentum from collapsing molecular cloud cores. Hall diffusion is known to be important to the magnetic field behaviour at many of the intermediate densities and field strengths encountered during the gravitational collapse of molecular cloud cores into protostars, and yet its role in the star formation process is not well-studied. This thesis describes a semianalytic self-similar model of the collapse of rotating isothermal molecular cloud cores with both Hall and ambipolar diffusion, presenting similarity solutions that demonstrate that the Hall effect has a profound influence on the dynamics of collapse. ... Hall diffusion also determines the strength of the magnetic diffusion and centrifugal shocks that bound the pseudo and rotationally-supported discs, and can introduce subshocks that further slow accretion onto the protostar. In cores that are not initially rotating Hall diffusion can even induce rotation, which could give rise to disc formation and resolve the magnetic braking catastrophe. The Hall effect clearly influences the dynamics of gravitational collapse and its role in controlling the magnetic braking and radial diffusion of the field would be worth exploring in future numerical simulations of star formation.

  19. Observation of a superfluid Hall effect

    PubMed Central

    Jiménez-García, Karina; Williams, Ross A.; Beeler, Matthew C.; Perry, Abigail R.; Phillips, William D.; Spielman, Ian B.

    2012-01-01

    Measurement techniques based upon the Hall effect are invaluable tools in condensed-matter physics. When an electric current flows perpendicular to a magnetic field, a Hall voltage develops in the direction transverse to both the current and the field. In semiconductors, this behavior is routinely used to measure the density and charge of the current carriers (electrons in conduction bands or holes in valence bands)—internal properties of the system that are not accessible from measurements of the conventional resistance. For strongly interacting electron systems, whose behavior can be very different from the free electron gas, the Hall effect’s sensitivity to internal properties makes it a powerful tool; indeed, the quantum Hall effects are named after the tool by which they are most distinctly measured instead of the physics from which the phenomena originate. Here we report the first observation of a Hall effect in an ultracold gas of neutral atoms, revealed by measuring a Bose–Einstein condensate’s transport properties perpendicular to a synthetic magnetic field. Our observations in this vortex-free superfluid are in good agreement with hydrodynamic predictions, demonstrating that the system’s global irrotationality influences this superfluid Hall signal. PMID:22699494

  20. Experiencing the Difference: The Role of Experiential Learning in Youth Development. Conference Report: The Brathay Youth Conference (Ambleside, England, July 5-6, 1999).

    ERIC Educational Resources Information Center

    White, Marian, Ed.

    This proceedings contains transcripts, presentations, and workshop summaries from a 2-day conference on experiential learning in youth development, held by the Brathay Hall Trust in the English Lake District. Brathay is a British educational charity that offers a variety of youth development courses, ranging from outdoor adventure activities to…

  1. CONSISTENT INFLAMMATORY RESPONSE FOLLOWING EXPOSURE TO CONCENTRATED AMBIENT PARTICLES (CAPS) DURING FALL SEASON IN WISTAR-KYOTO RATS

    EPA Science Inventory

    CONSISTENT INFLAMMATORY RESPONSE FOLLOWING EXPOSURE TO CONCENTRATED AMBIENT PARTICLES (CAPs) DURING FALL SEASON IN WISTAR-KYOTO RATS.
    UP Kodavanti, MC Schladweiler, AD Ledbetter, LC Walsh, PS Gilmour, MI Gilmour, WP Watkinson, JP Nolan, JH Richards, D Andrews, DL Costa. US EPA...

  2. CCD system upgrading of the Kyoto3DII and integral field spectroscopic observation with the new system

    NASA Astrophysics Data System (ADS)

    Mitsuda, Kazuma; Hashiba, Yasuhito; Minowa, Yosuke; Hayano, Yutaka; Sugai, Hajime; Shimono, Atsushi; Matsubayashi, Kazuya; Hattori, Takashi; Kamata, Yukiko; Ozaki, Shinobu; Doi, Mamoru; Sako, Shigeyuki

    2016-08-01

    The Kyoto Tridimensional Spectrograph II (Kyoto 3DII) is an optical integral field spectrograph mounted on the Subaru telescope as a PI-type instrument. Used with AO188, Kyoto 3DII provides us unique opportunities of optical Integral Field Spectroscopy (IFS) with adaptive optics (AO). While AO works better in redder wavelength regions, quantum efficiency of the previous CCD was low there with optimization for a wider wavelength coverage. To optimize Kyoto 3DII to AO observations, we have newly installed the red-sensitive Hamamatsu fully depleted CCD, which enhances the system efficiency by a factor of 2 in the red wavelength range. Fringes are dramatically reduced, and the readout noise drops to 3:2-3:4e- about two times smaller than previous, due to refrigerator and readout system. With these improvements, we carried out engineering and scientific observations in September 2015, February and March 2016. We measured the system efficiency using a standard star, and confirmed the successful improvement of the system efficiency. We observed galactic nuclei of nearby galaxies in the Natural Guide Star (NGS) and the Laser Guide Star (LGS) modes. We found the spatial resolution of 0.1'' FWHM using a 9.5-magnitude NGS, and 0.2 - 0:4'' in LGS mode. Together with the AO resolution, improved efficiency opens a new window for Kyoto 3DII to carry out high resolution optical IFS targeting faint objects such as high-redshift galaxies as well as faint lines such as [OI] λ6300° A and absorption lines of nearby objects.

  3. 75 FR 22770 - Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment April 22, 2010. In accordance with the National Environmental Policy Act of 1969, as amended,...

  4. Charge carrier coherence and Hall effect in organic semiconductors.

    PubMed

    Yi, H T; Gartstein, Y N; Podzorov, V

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

  5. Charge carrier coherence and Hall effect in organic semiconductors

    SciTech Connect

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Lastly, our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

  6. Charge carrier coherence and Hall effect in organic semiconductors

    PubMed Central

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-01-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor. PMID:27025354

  7. Edge reconstructions in fractional quantum Hall systems.

    NASA Astrophysics Data System (ADS)

    Joglekar, Yogesh; Nguyen, Hoang; Murthy, Ganpathy

    2003-03-01

    Two dimensional electron systems exhibiting fractional quantum Hall effects are characterized by a quantized Hall conductance and a dissipationless bulk. The transport in these systems occurs only at the edges where gapless excitations are possible [1]. We present a microscopic calculation of these egde-states at filling factors ν=1/3 and ν=2/5 using the Hamiltonian theory of the fractional quantum Hall effect [2]. We find that the quantum Hall egde undergoes a reconstruction as the confining potential, produced by the background charge density, softens [3,4]. Our results have implications to the tunneling experiments into the edge of a fractional quantum Hall system [5]. 1: X. G.Wen, Phys. Rev. Lett. 64, 2206 (1990). 2: R. Shankar and G. Murthy, Phys. Rev. Lett. 79, 4437 (1997). 3: C. de C. Chamon and X. G. Wen, Phys. Rev. B 49, 8227 (1994). 4: X. Wan, K. Yang, and E. H. Razayi, Phys. Rev. Lett. 88, 056802 (2002). 5: A.M.Chang et al., Phys. Rev. Lett. 86, 143 (2000).

  8. APFBC repowering could help meet Kyoto Protocol CO{sub 2} reduction goals[Advanced Pressurized Fluidized Bed Combustion

    SciTech Connect

    Weinstein, R.E.; Tonnemacher, G.C.

    1999-07-01

    The Clinton Administration signed the 1997 Kyoto Protocol agreement that would limit US greenhouse gas emissions, of which carbon dioxide (CO{sub 2}) is the most significant. While the Kyoto Protocol has not yet been submitted to the Senate for ratification, in the past, there have been few proposed environmental actions that had continued and wide-spread attention of the press and environmental activists that did not eventually lead to regulation. Since the Kyoto Protocol might lead to future regulation, its implications need investigation by the power industry. Limiting CO{sub 2} emissions affects the ability of the US to generate reliable, low cost electricity, and has tremendous potential impact on electric generating companies with a significant investment in coal-fired generation, and on their customers. This paper explores the implications of reducing coal plant CO{sub 2} by various amounts. The amount of reduction for the US that is proposed in the Kyoto Protocol is huge. The Kyoto Protocol would commit the US to reduce its CO{sub 2} emissions to 7% below 1990 levels. Since 1990, there has been significant growth in US population and the US economy driving carbon emissions 34% higher by year 2010. That means CO{sub 2} would have to be reduced by 30.9%, which is extremely difficult to accomplish. The paper tells why. There are, however, coal-based technologies that should be available in time to make significant reductions in coal-plant CO{sub 2} emissions. Th paper focuses on one plant repowering method that can reduce CO{sub 2} per kWh by 25%, advanced circulating pressurized fluidized bed combustion combined cycle (APFBC) technology, based on results from a recent APFBC repowering concept evaluation of the Carolina Power and Light Company's (CP and L) L.V. Sutton steam station. The replacement of the existing 50-year base of power generating units needed to meet proposed Kyoto Protocol CO{sub 2} reduction commitments would be a massive undertaking. It is

  9. Piezo Voltage Controlled Planar Hall Effect Devices

    PubMed Central

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K. W.; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-01-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials. PMID:27329068

  10. Quantized photonic spin Hall effect in graphene

    NASA Astrophysics Data System (ADS)

    Cai, Liang; Liu, Mengxia; Chen, Shizhen; Liu, Yachao; Shu, Weixing; Luo, Hailu; Wen, Shuangchun

    2017-01-01

    We examine the photonic spin Hall effect (SHE) in a graphene-substrate system with the presence of an external magnetic field. In the quantum Hall regime, we demonstrate that the in-plane and transverse spin-dependent splittings in the photonic SHE exhibit different quantized behaviors. The quantized SHE can be described as a consequence of a quantized geometric phase (Berry phase), which corresponds to the quantized spin-orbit interaction. Furthermore, an experimental scheme based on quantum weak value amplification is proposed to detect the quantized SHE in the terahertz frequency regime. By incorporating the quantum weak measurement techniques, the quantized photonic SHE holds great promise for detecting quantized Hall conductivity and the Berry phase. These results may bridge the gap between the electronic SHE and photonic SHE in graphene.

  11. Hall Effect in Neutron Star Crusts

    NASA Astrophysics Data System (ADS)

    Gourgouliatos, K. N.; Cumming, A.

    2014-08-01

    The crust of Neutron Stars can be approximated by a highly conducting solid crystal lattice. The evolution of the magnetic field in the crust is mediated through Hall effect, namely the electric current is carried by the free electrons of the lattice and the magnetic field lines are advected by the electron fluid. Here, we present the results of a time-dependent evolution code which shows the effect Hall drift has in the large-scale evolution of the magnetic field. In particular we link analytical predictions with simulation results. We find that there are two basic evolutionary paths, depending on the initial conditions compared to Hall equilibrium. We also show the effect axial symmetry combined with density gradient have on suppressing turbulent cascade.

  12. Hall-magnetohydrodynamic turbulence with electron inertia

    NASA Astrophysics Data System (ADS)

    Martin, L. N.; Andres, N.; Dmitruk, P.; Gomez, D. O.

    2013-12-01

    The magnetohydrodynamic (one-fluid) model is often regarded as a reasonable description of the dynamics of a plasma. One-fluid models are useful in the context of large scale dynamics, but when a more detailed description is needed (for instance, when the physical context favors the development of small scales) it is most appropriate to consider two-fluid models. Within the framework of two-fluid MHD for a fully ionized hydrogen plasma, we study the effect of the Hall term and electron inertia in MHD turbulence, observing whether these effects change the energy cascade, the characteristic scales of the flow and the dynamics of global magnitudes, with particular interest in the dissipation processes. Numerical simulations of freely evolving three-dimensional reduced magnetohydrodynamics (RHMHD) and 2.5-D Hall-MHD including electron inertia are performed for different values of the ion and electron skin depth (controlling the impact of the Hall term and the electron inertia).

  13. Logarithmic correlations in quantum Hall plateau transitions

    NASA Astrophysics Data System (ADS)

    Vasseur, Romain

    2015-07-01

    The critical behavior of quantum Hall transitions in two-dimensional disordered electronic systems can be described by a class of complicated, nonunitary conformal field theories with logarithmic correlations. The nature and the physical origin of these logarithmic correlation functions remain, however, mysterious. Using the replica trick and the underlying symmetries of these quantum critical points, we show here how to construct nonperturbatively disorder-averaged observables in terms of Green's functions that scale logarithmically at criticality. In the case of the spin quantum Hall transition, which may occur in disordered superconductors with spin-rotation symmetry and broken time reversal invariance, we argue that our results are compatible with an alternative approach based on supersymmetry. The generalization to the integer quantum Hall plateau transition is also discussed.

  14. Hall coefficient measurement for nondestructive materials characterization

    NASA Astrophysics Data System (ADS)

    Nagy, Peter B.

    2013-01-01

    Although Hall detectors are widely used for magnetic flux density measurements in numerous electromagnetic NDE applications, measurement of the Hall coefficient of metals and their alloys for NDE purposes has not been successfully attempted before. While other intrinsic electric properties, such as electric conductivity and, to a lesser degree, thermoelectric power, are widely used for NDE, Hall coefficient measurements have never been really considered mainly because the measurements are rather difficult to carry out, especially in high-conductivity materials. In contrast to electric conductivity, the Hall coefficient is influenced mainly by the concentration density of the free charge carriers, i.e., electrons in metals, and not so much by their mobility, therefore it could be a valuable addition to our NDE arsenal. We modified the alternating current potential drop (ACPD) method with square-electrode configuration by adding an external bias magnetic field modulation to measure the Hall coefficient. The presence of such a bias field violates the Reciprocity Theorem unless the sign of the magnetic field is switched between the two measurements, which can be exploited to measure the Hall coefficient in the presence of other variations that would otherwise hide it. This new experimental method was tested on paramagnetic alloys and yielded a ±4% reproducibility that probably could be further improved by additional development efforts. As a first step towards illustrating some of the potential applications of this new technique, we have done reversible applied stress measurements in Al 1100 plates and found the sensitivity of the technique to elastic strain surprisingly high.

  15. Forced reconnection in the Hall limit

    NASA Astrophysics Data System (ADS)

    Huba, J. D.

    2006-12-01

    We present new numerical results of the dynamics of forced magnetic reconnection in the Hall limit using the NRL Hall MHD code VooDoo. The system is forced by imposing inflow boundary conditions on the plasma density and velocity, and the magnetic field. A magnetic field of opposite polarity is injected from opposite boundaries. The inflow velocity is spatially uniform but the density profile is spatially nonuniform which allows an X-line to develop and magnetic reconnection to proceed. We present simulation results for various inflow conditions in both 2D and 3D geometries. We apply our results to laboratory and space plasma processes. Research supported by ONR and NASA.

  16. Forced Reconnection in the Hall Limit

    NASA Astrophysics Data System (ADS)

    Huba, J.

    2006-10-01

    We present new numerical results of the dynamics of forced magnetic reconnection in the Hall limit using the NRL Hall MHD code VooDoo. The system is forced by imposing inflow boundary conditions on the plasma density and velocity, and the magnetic field. A magnetic field of opposite polarity is injected from opposite boundaries. The inflow velocity is spatially uniform but the density profile is spatially nonuniform which allows an X-line to develop and magnetic reconnection to proceed. We present simulation results for various inflow conditions in both 2D and 3D geometries. We apply our results to laboratory and space plasma processes.

  17. Integer quantum Hall effect in graphene

    NASA Astrophysics Data System (ADS)

    Jellal, Ahmed

    2016-04-01

    We study the quantum Hall effect in a monolayer graphene by using an approach based on thermodynamical properties. This can be done by considering a system of Dirac particles in an electromagnetic field and taking into account of the edges effect as a pseudo-potential varying continuously along the x direction. At low temperature and in the weak electric field limit, we explicitly determine the thermodynamical potential. With this, we derive the particle numbers in terms of the quantized flux and therefore the Hall conductivity immediately follows.

  18. Prototype dining hall energy efficiency study

    SciTech Connect

    Mazzucchi, R.P.; Bailey, S.A.; Zimmerman, P.W.

    1988-06-01

    The energy consumption of food service facilities is among the highest of any commercial building type, owing to the special requirements for food preparation, sanitation, and ventilation. Consequently, the US Air Force Engineering and Services Center (AFESC) contracted with Pacific Northwest Laboratory (PNL) to collect and analyze end-use energy consumption data for a prototypical dining hall and make specific recommendations on cost-effective energy conservation options. This information will be used to establish or update criteria for dining hall designs and retrofits as appropriate. 6 refs., 21 figs., 23 tabs.

  19. Inverse spin Hall effect by spin injection

    NASA Astrophysics Data System (ADS)

    Liu, S. Y.; Horing, Norman J. M.; Lei, X. L.

    2007-09-01

    Motivated by a recent experiment [S. O. Valenzuela and M. Tinkham, Nature (London) 442, 176 (2006)], the authors present a quantitative microscopic theory to investigate the inverse spin-Hall effect with spin injection into aluminum considering both intrinsic and extrinsic spin-orbit couplings using the orthogonalized-plane-wave method. Their theoretical results are in good agreement with the experimental data. It is also clear that the magnitude of the anomalous Hall resistivity is mainly due to contributions from extrinsic skew scattering.

  20. Proton Knock-Out in Hall A

    SciTech Connect

    Kees de Jager

    2002-06-01

    Proton knock-out is studied in a broad program in Hall A at Jefferson Lab. The first experiment performed in Hall A studied the {sup 16}O(e,e'p) reaction. Since then proton knock-out experiments have studied a variety of aspects of that reaction, from single-nucleon properties to its mechanism, such as final-state interactions and two-body currents, in nuclei from {sup 2}H to {sup 16}O. In this review the results of this program will be summarized and an outlook given of future accomplishments.

  1. Enhanced Performance of Cylindrical Hall Thrusters

    SciTech Connect

    Y. Raitses, A. Smirnov, and N.J. Fisch

    2007-05-14

    The cylindrical thruster differs significantly in its underlying physical mechanisms from the conventional annular Hall thruster. It features high ionization efficiency, quiet operation, ion acceleration in a large volume-to-surface ratio channel, and performance comparable with the state-of-the-art conventional Hall thrusters. Very significant plume narrowing, accompanied by the increase of the energetic ion fraction and improvement of ion focusing, led to 50%–60% increase of the thruster anode efficiency. These improvements were achieved by overrunning the discharge current in the magnetized thruster plasma.

  2. Classical and instrumental conditioning of eyeblink responses in Wistar-Kyoto and Sprague-Dawley rats.

    PubMed

    Ricart, Thomas M; Jiao, Xilu; Pang, Kevin C H; Beck, Kevin D; Servatius, Richard J

    2011-01-01

    Wistar-Kyoto (WKY) rats, an animal model of anxiety vulnerability, acquire lever-press avoidance faster than outbred Sprague-Dawley (SD) rats. Faster avoidance acquisition may reflect an inherent ability to acquire cue-outcome associations, response-outcome associations or both. To evaluate cue-outcome learning, acquisition of classically conditioned eyeblink response was compared in SD and WKY rats using a delay-type paradigm (500-ms conditioned stimulus (CS) coterminating with a 10-ms unconditional stimulus (US)). WKY rats demonstrated enhanced classical conditioning, with both faster acquisition and greater asymptotic performance in delay-type training than SD rats. To evaluate response-outcome learning, separate SD and WKY rats were given control over US delivery through imposition of an omission contingency into delay-type training (emitting a conditioned response (CR) prevented delivery of the US). The schedule of US delivery derived by these rats became the training regimen for a separate group of SD and WKY rats, yoked within strain. In SD rats, no differences in acquisition were detected between those given control over US delivery and those trained with the same partial reinforcement schedule. Acquisition rates of those WKY rats with control exceeded those trained with a yoked-schedule of US presentation. Collectively, WKY rats exhibit enhanced classical conditioning and sensitivity to schedules of reinforcement compared to outbred SD rats. Anxiety vulnerability, in particular inhibited temperament, may be traced to active processes in the prediction and control of aversive events.

  3. Dysfunctional Inhibitory Mechanisms in Locus Coeruleus Neurons of the Wistar Kyoto Rat

    PubMed Central

    Bruzos-Cidón, C; Llamosas, N; Ugedo, L

    2015-01-01

    Background: The noradrenergic nucleus locus coeruleus (LC) has functional relevance in several psychopathologies such as stress, anxiety, and depression. In addition to glutamatergic and GABAergic synaptic inputs, the activation of somatodendritic α2-adrenoceptors is the main responsible for LC activity regulation. The Wistar Kyoto (WKY) rat exhibits depressive- and anxiety-like behaviors and hyperresponse to stressors. Thus, the goal of the present study was to investigate in vitro the sensitivity of α2-adrenoceptors, as well as the glutamatergic and GABAergic synaptic activity on LC neurons of the WKY strain. Methods: For that purpose patch-clamp whole-cell recordings were done in LC slices. Results: The α2-adrenoceptors of LC neurons from WKY rats were less sensitive to the effect induced by the agonist UK 14 304 as compared to that recorded in the Wistar (Wis) control strain. In addition, the GABAergic input to LC neurons of WKY rats was significantly modified compared to that in Wis rats, since the amplitude of spontaneous GABAergic postsynaptic currents was reduced and the half-width increased. On the contrary, no significant alterations were detected regarding glutamatergic input to LC neurons between rat strains. Conclusions: These results point out that in WKY rats the inhibitory control exerted by α2-adrenoceptors and GABAergic input onto LC neurons is dysregulated. Overall, this study supports in this animal model the hypothesis that claims an imbalance between the glutamatergic-GABAergic systems as a key factor in the pathophysiology of depression. PMID:25586927

  4. Cocaine self-administration in Wistar-Kyoto rats: a behavioral and biochemical analysis.

    PubMed

    Jastrzębska, Joanna; Frankowska, Małgorzata; Szumiec, Łukasz; Sadakierska-Chudy, Anna; Haduch, Anna; Smaga, Irena; Bystrowska, Beata; Daniel, Wladyslawa A; Filip, Małgorzata

    2015-10-15

    Depression and cocaine abuse disorders are common concurrent diagnoses. In the present study, we employed Wistar-Kyoto (WKY) rats that showed a depressive-like phenotype to study intravenous cocaine self-administration and extinction/reinstatement procedures. We also investigated the basal tissue level of neurotransmitters, their metabolites and plasma corticosterone (CORT) concentrations in WKY rats, bulbectomized (OBX) rats, and control rats. The WKY rats exhibited an attenuation of the cocaine-associated lever presses and cocaine intake during the acquisition/maintenance of cocaine self-administration only under specific conditions. Active lever presses exhibited by the WKY rats and control animals did not differ during the extinction training and cocaine-seeking behaviors. The WKY rats demonstrated alterations in the basal levels of dopamine, norepinephrine, and serotonin in selected brain structures involved in depression and drug addiction. The changes in the level of neurotransmitters in these animals refer not only to the control (Wistar) rats but also to bulbectomized animals, which represent another depression model. Furthermore, we identified unchanged levels of CORT in the WKY and OBX rats during the light phase and free-stress conditions. This finding suggests that WKY rats should not be used to investigate the co-occurrence of depression and cocaine addiction, as this rat strain does not show an enhanced risk of relapse.

  5. New Wistar Kyoto and spontaneously hypertensive rat transgenic models with ubiquitous expression of green fluorescent protein

    PubMed Central

    Garcia Diaz, Ana Isabel; Moyon, Ben; Coan, Philip M.; Alfazema, Neza; Venda, Lara; Woollard, Kevin; Aitman, Tim

    2016-01-01

    ABSTRACT The Wistar Kyoto (WKY) rat and the spontaneously hypertensive (SHR) rat inbred strains are well-established models for human crescentic glomerulonephritis (CRGN) and metabolic syndrome, respectively. Novel transgenic (Tg) strains add research opportunities and increase scientific value to well-established rat models. We have created two novel Tg strains using Sleeping Beauty transposon germline transgenesis, ubiquitously expressing green fluorescent protein (GFP) under the rat elongation factor 1 alpha (EF1a) promoter on the WKY and SHR genetic backgrounds. The Sleeping Beauty system functioned with high transgenesis efficiency; 75% of new rats born after embryo microinjections were transgene positive. By ligation-mediated PCR, we located the genome integration sites, confirming no exonic disruption and defining a single or low copy number of the transgenes in the new WKY-GFP and SHR-GFP Tg lines. We report GFP-bright expression in embryos, tissues and organs in both lines and show preliminary in vitro and in vivo imaging data that demonstrate the utility of the new GFP-expressing lines for adoptive transfer, transplantation and fate mapping studies of CRGN, metabolic syndrome and other traits for which these strains have been extensively studied over the past four decades. PMID:26769799

  6. WTC deafness Kyoto (dfk): a rat model for extensive investigations of Kcnq1 functions.

    PubMed

    Gohma, Hiroshi; Kuramoto, Takashi; Kuwamura, Mitsuru; Okajima, Ryoko; Tanimoto, Noriaki; Yamasaki, Ken-ichi; Nakanishi, Satoshi; Kitada, Kazuhiro; Makiyama, Takeru; Akao, Masaharu; Kita, Toru; Sasa, Masashi; Serikawa, Tadao

    2006-02-14

    KCNQ1 forms K+ channels by assembly with regulatory subunit KCNE proteins and plays a key role in the K+ homeostasis in a variety of tissues. In the heart, KCNQ1 is coassembled with KCNE1 to produce a cardiac delayed rectifier K+ current. In the inner ear, the KCNQ1/KCNE1 complex maintains the high concentration of K+ in the endolymph. In the stomach, KCNQ1 is coassembled with KCNE2 to form the K+ exflux channel that is essential for gastric acid secretion. In the colon and small intestine, KCNQ1 is coassembled with KCNE3 to play an important role in transepithelial cAMP-stimulated Cl- secretion. For further understanding of Kcnq1 function in vivo, an animal model has been required. Here we reported the identification of a coisogenic Kcnq1 mutant rat, named deafness Kyoto (dfk), and the characterization of its phenotypes. WTC-dfk rats carried intragenic deletion at the Kcnq1 gene and showed impaired gain of weight, deafness, and imbalance resulting from the marked reduction of endolymph, prolonged QT interval in the electrocardiogram (ECG), and gastric achlorhydria associated with hypertrophic gastric mucosa. Surprisingly, WTC-dfk rats showed hypertension, which suggested that Kcnq1 might be involved in the regulation of blood pressure. These findings suggest that WTC-dfk rats could represent a powerful tool for studying the physiological functions of KCNQ1 and for the establishment of new therapeutic procedures for Kcnq1-related diseases.

  7. Cofiring fossil fuels with renewable energy in addressing global climate change and the Kyoto Protocol

    SciTech Connect

    Miller, C.L.; Hoppe, J.A.

    1998-12-31

    In addressing the issue of Global Climate Change, the use of renewable energy resources and energy efficiency has been traditionally touted as the most effective way to mitigate the production of greenhouse gases and to sequester carbon-based emissions resulting from the use of fossil fuels for the worldwide production of power. The goal set by the Kyoto Protocol of ``stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the atmosphere`` will not be met unless the predictions for world energy production based on the use of oil, gas and coal are considered in using renewable energy resources. The use of renewable energy in the US amounted to 7.4 quads in 1997 which was only 7.8% of total domestic gross energy demand. In the US alone the biomass renewable energy economically accessible resource base is estimated at 14 quads per year which can be considered for use in addressing predicted increases in electric power demand. In 1990 the biomass generated power was 3.1 quads in the US alone, and renewable energy accounted for 14.7% of the total world power production allowing for significant increases in the future. The most significant use of renewable energy other than the power sector is the use of biofuels (principally from wood) in the industrial sector which accounts for 21% of the total renewable demand of 7.432 quads in 1997.

  8. Daytime mother-calf relationships in reticulated giraffes (Giraffa cameloparadalis reticulate) at the Kyoto City Zoo.

    PubMed

    Nakamichi, Masayuki; Murata, Chisa; Eto, Ryo; Takagi, Naoko; Yamada, Kazunori

    2015-01-01

    The present study quantitatively assesses the relationships between a reticulated giraffe mother and her first- and second-born calves during the first 22 months of the older calf's and the first 12 months of the younger calf's life at the Kyoto City Zoo, Japan. The mother permitted her calves to suckle at over 70% of their suckling attempts in the first month after their births, and the calves ceased suckling spontaneously in 65 to 70% of the suckling bouts. From the second month on, she showed a clear tendency to reject the calves' suckling attempts and terminated almost all of their suckling bouts, which resulted in approximately 60 sec or less of suckling duration per bout. The frequency of proximity between the mother and her calves remained at 20 to 30% throughout the first year, with no apparent developmental changes being evident. The mother was mainly responsible for terminating proximity by walking away from her calves throughout their first year after birth, while both calves were mainly responsible for attempting proximity by approaching their mother after reaching 2 months of age. Our study also showed that the giraffe mother became pregnant again while nursing her calves and ceased lactation (i.e., weaned the calves) before the fetus's growth started accelerating.

  9. Genetic architecture of Wistar-Kyoto rat and spontaneously hypertensive rat substrains from different sources.

    PubMed

    Zhang-James, Yanli; Middleton, Frank A; Faraone, Stephen V

    2013-07-02

    The spontaneously hypertensive rat (SHR) has been widely used as a model for studies of hypertension and attention deficit/hyperactivity disorder. The inbred Wistar-Kyoto (WKY) rat, derived from the same ancestral outbred Wistar rat as the SHR, are normotensive and have been used as the closest genetic control for the SHR, although the WKY has also been used as a model for depression. Notably, however, substantial behavioral and genetic differences among the WKY substrains, usually from the different vendors and breeders, have been observed. These differences have often been overlooked in prior studies, leading to inconsistent and even contradictory findings. The complicated breeding history of the SHR and WKY rats and the lack of a comprehensive understanding of the genetic background of different commercial substrains make the selection of control rats a daunting task, even for researchers who are mindful of their genetic heterogeneity. In this study, we examined the genetic relationship of 16 commonly used WKY and SHR rat substrains using genome-wide SNP genotyping data. Our results confirmed a large genetic divergence and complex relationships among the SHR and WKY substrains. This understanding, although incomplete without the genome sequence, provides useful guidance in selecting substrains and helps to interpret previous reports when the source of the animals was known. Moreover, we found two closely related, yet distinct WKY substrains that may provide novel opportunities in modeling psychiatric disorders.

  10. Contextual view of ILWU Hall, facing southsouthwest, with ocean bank ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Contextual view of ILWU Hall, facing south-southwest, with ocean bank visible in the background - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

  11. Contextual view of ILWU Hall, facing northwest with commercial port ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Contextual view of ILWU Hall, facing northwest with commercial port buildings visible in the background - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

  12. Interior detail of platform in main hall, with desk, flag, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior detail of platform in main hall, with desk, flag, and banners, facing south - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

  13. Contextual view of ILWU Hall, facing east, with the city ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Contextual view of ILWU Hall, facing east, with the city of Port Hueneme visible in the background - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

  14. Interior view of central hall from bedroom 2 showing linen ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of central hall from bedroom 2 showing linen dresser, facing southwest. - Albrook Air Force Station, Non-Commissioned Officers' Duplex, East side of Hall Street, Balboa, Former Panama Canal Zone, CZ

  15. 24. BEDROOM #1 INTERIOR SHOWING OPEN DOOR TO HALL WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. BEDROOM #1 INTERIOR SHOWING OPEN DOOR TO HALL WITH HALL LINEN CLOSETS VISIBLE IN BACKGROUND, AND PARTIALLY OPEN DOOR TO CLOSET. VIEW TO EAST. - Big Creek Hydroelectric System, Powerhouse 8, Operator Cottage, Big Creek, Big Creek, Fresno County, CA

  16. 13. Historic American Buildings Survey, BINGHAMTON CITY HALL, PHOTOCOPY OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Historic American Buildings Survey, BINGHAMTON CITY HALL, PHOTOCOPY OF ORIGINAL COMPETITION DRAWING OF FIRST FLOOR PLAN - 1896 FROM THE OFFICE OF THE CITY ENGINEER, BINGHAMTON, NEW YORK. - Binghamton City Hall, Collier Street, Binghamton, Broome County, NY

  17. 9. Historic American Buildings Survey, BINGHAMTON CITY HALL, PHOTOCOPY OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Historic American Buildings Survey, BINGHAMTON CITY HALL, PHOTOCOPY OF ORIGINAL COMPETITION DRAWING (GENERAL PERSPECTIVE) - 1896 FROM THE OFFICE OF THE CITY ENGINEER, BINGHAMTON, NEW YORK. - Binghamton City Hall, Collier Street, Binghamton, Broome County, NY

  18. 10. Historic American Buildings Survey, BINGHAMTON CITY HALL, PHOTOCOPY OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Historic American Buildings Survey, BINGHAMTON CITY HALL, PHOTOCOPY OF ORIGINAL COMPETITION DRAWING OF A LONGITUDINAL SECTION - 1896 FROM THE OFFICE OF THE CITY ENGINEER, BINGHAMTON, NEW YORK. - Binghamton City Hall, Collier Street, Binghamton, Broome County, NY

  19. Improved Readout For Micromagnet/Hall-Effect Memories

    NASA Technical Reports Server (NTRS)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.

    1993-01-01

    Two improved readout circuits for micromagnet/Hall-effect random-access memories designed to eliminate current shunts introducing errors into outputs of older readout circuits. Incorporate additional switching transistors to isolate Hall sensors as needed.

  20. [Experience of Collaborative Research through Department of Medical Instrumental Research and Technology in Kyoto Prefectural University of Medicine].

    PubMed

    Saitoh, Kensuke

    2016-01-01

    Both of Kyoto Prefectural University of Medicine which offers high, technical and safe medical treatment and Horiba, Ltd. which has small CBC analyzers in a core product established a joint research institute for development of advanced laboratory test analyzer from January 1, 2012 in Kyoto Prefectural University of Medicine as the "advanced treatment hospital" where the Ministry of Health, Labour and Welfare has got approved. Clinical needs about analyzer and reagent for a laboratory test are being investigated to the emergency medical care unit and the intensive care unit as well as the laboratory test part in the affiliated hospital and many medical departments of the pediatrics, the internal medicine and the surgery. Developing the new analyzer based on high technology, evaluating the performance of them and spreading them to a medical examination and treatment site is our main target.

  1. Promoting Health During the American Occupation of Japan The Public Health Section, Kyoto Military Government Team, 1945-1949

    PubMed Central

    Nishimura, Sey

    2008-01-01

    During the American occupation of Japan (1945–1952), young public health officers from the US Army Medical Corps were posted in local US Army military government teams. These young doctors (aged 25 to 27 years), who had not absorbed the strong anti-Japanese tradition of the US military during World War II, seem to have alleviated the initial resentment felt by the Japanese toward the new governors of their homeland. The case of the Kyoto Military Government Team illustrates the Kyoto citizenry’s positive view of some American-directed public health measures. The team’s services helped to counter widely held negative views on colonialism, occupation, and public health; lessened resentment toward the unilateral command structure of the occupation forces; and contributed to improved relations between the United States and Japan at the local level. PMID:18235076

  2. Anomalous Josephson Hall effect in magnet/triplet superconductor junctions

    NASA Astrophysics Data System (ADS)

    Yokoyama, Takehito

    2015-11-01

    We investigate anomalous Hall effect in a magnet coupled to a triplet superconductor under phase gradient. It is found that the anomalous Hall supercurrent arises from the nontrivial structure of the magnetization. The magnetic structure manifested in the Hall supercurrent is characterized by even order terms of the exchange coupling, essentially different from that discussed in the context of anomalous Hall effect, reflecting the dissipationless nature of the supercurrent. We also discuss a possible candidate for magnetic structure to verify our prediction.

  3. Intrinsic spin and orbital angular momentum Hall effect.

    PubMed

    Zhang, S; Yang, Z

    2005-02-18

    A generalized definition of intrinsic and extrinsic transport coefficients is introduced. We show that transport coefficients from the intrinsic origin are solely determined by local electronic structure, and thus the intrinsic spin Hall effect is not a transport phenomenon. The intrinsic spin Hall current is always accompanied by an equal but opposite intrinsic orbital angular momentum Hall current. We prove that the intrinsic spin Hall effect does not induce a spin accumulation at the edge of the sample or near the interface.

  4. PREFACE: Proceedings of the International Conference on Highly Frustrated Magnetism, Osaka, Japan, 15 19 August 2006

    NASA Astrophysics Data System (ADS)

    Hiroi, Zenji; Tsunetsugu, Hirokazu; Kawamura, H.

    2007-04-01

    The Highly Frustrated Magnetism 2006 (HFM 2006) conference took place on 15-19 August 2006 at the Icho Kaikan of Osaka University, Osaka, Japan. This conference was the third one of the series, following the first one in Waterloo, Canada (HFM 2000) [1] and the second one in Grenoble, France (HFM 2003) [2]. The HFM 2006 conference was held as a satellite of the International Conference on Magnetism (ICM 2006) held on 20-25 August 2006 in Kyoto, Japan. The conference attracted 191 participants from all over the world. The number of participants of the HFM conference series has been increasing steadily, from about 80 participants for HFM 2000 and about 120 participants for HFM 2003, demonstrating that highly frustrated magnetism is a rapidly growing area for research in condensed matter physics. The HFM 2006 conference consisted of four plenary talks by H Takagi, F Mila, P Mendels and B D Gaulin, 18 invited presentations and about 120 poster presentations from all areas of frustrated magnetism. In the evening on the 18th of August, a special session about 'the kagome story' was given by M. Mekata, where participants learned about the history of early-day research on frustrated magnetism and the origin of the word 'kagome' (see the picture below). Kagome lattice in a traditional Japanese woven basket Kagome lattice from a Japanese traditional woven bamboo basket. During the conference period, many stimulating discussions were held both inside and outside the conference room. The subjects covered in the conference included: Quantum frustrated magnetism and spin liquids Novel ordering of geometrically frustrated magnets Itinerant frustrated systems and novel superconductivity Spin glasses and random magnets Frustration effect on the coupling to lattice, orbital and charge degrees of freedom Exotic phenomena induced by macroscopic degeneracy Field effect on frustrated magnetism etc. This special issue of Journal of Physics: Condensed Matter is devoted to the proceedings

  5. Towards a Better Understanding of the Anomalous Hall Effect

    NASA Astrophysics Data System (ADS)

    Yue, Di; Jin, Xiaofeng

    2017-01-01

    Recent experimental efforts to identify the intrinsic and extrinsic contributions in the anomalous Hall effect are reviewed. Benefited from the experimental control of artificial impurity density in single crystalline magnetic thin films, a comprehensive physical picture of the anomalous Hall effect involving multiple competing scattering processes has been established. Some new insights into the microscopic mechanisms of the anomalous Hall effect are discussed.

  6. Improved Hall-Effect Sensors For Magnetic Memories

    NASA Technical Reports Server (NTRS)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.; Chen, Y. C.; Bhattacharya, Pallab K.

    1993-01-01

    High-electron-mobility sensor films deposited on superlattice buffer (strain) layers. Improved Hall-effect sensors offer combination of adequate response and high speed needed for use in micromagnet/Hall-effect random-access memories. Hall-effect material chosen for use in sensors is InAs.

  7. Hall probe response to a distribution of vortices in superconductor

    NASA Astrophysics Data System (ADS)

    Reiderman, A.; Wolfus, Y.; Abulafia, Y.; Yeshurun, Y.

    1993-04-01

    Based on an analytical approach, an approximation of the Hall probe local sensitivity function by the square uniformly sensitive region w×w, where w is the distance between the Hall electrodes, is given. A simple formula for the Hall probe response to a distribution of vortices in superconductors is proposed.

  8. Destruction of the Fractional Quantum Hall Effect by Disorder

    DOE R&D Accomplishments Database

    Laughlin, R. B.

    1985-07-01

    It is suggested that Hall steps in the fractional quantum Hall effect are physically similar to those in the ordinary quantum Hall effect. This proposition leads to a simple scaling diagram containing a new type of fixed point, which is identified with the destruction of the fractional states by disorder. 15 refs., 3 figs.

  9. Parametric Investigations of Non-Conventional Hall Thruster

    SciTech Connect

    Raitses, Y.; Fisch, N.J.

    2001-01-12

    Hall thrusters might better scale to low power with non-conventional geometry. A 9 cm cylindrical, ceramic-channel, Hall thruster with a cusp-type magnetic field distribution has been investigated. It exhibits discharge characteristics similar to conventional coaxial Hall thrusters, but does not expose as much channel surface. Significantly, its operation is not accompanied by large amplitude discharge low frequency oscillations.

  10. PREFACE: MCWASP XIV: International Conference on Modelling of Casting, Welding and Advanced Solidification Processes

    NASA Astrophysics Data System (ADS)

    Yasuda, H.

    2015-06-01

    The current volume represents contributed papers of the proceedings of the 14th international conference on ''Modeling of Casting, Welding and Advanced Solidification Processes (MCWASP XIV)'', Yumebutai International Conference Center, Awaji island, Hyogo, Japan on 21 - 26 June, 2016. The first conference of the series 'Modeling of Casting, Welding and Advanced Solidification Processes (MCWASP)' was started up in 1980, and this is the 14th conference. The participants are more than 100 scientists from industry and academia, coming from 19 countries. In the conference, we have 5 invited, 70 oral and 31 poster presentations on different aspects of the modeling. The conference deals with various casting processes (Ingot / shape casting, continuous casting, direct chill casting and welding), fundamental phenomena (nucleation and growth, dendritic growth, eutectic growth, micro-, meso- and macrostructure formation and defect formation), coupling problems (electromagnetic interactions, application of ultrasonic wave), development of experimental / computational methods and so on. This volume presents the cutting-edge research in the modeling of casting, welding and solidification processes. I would like to thank MAGMA Giessereitechnologie GmbH, Germany and SCSK Corporation, Japan for supporting the publication of contributed papers. Hideyuki Yasuda Conference Chairman Department of Materials Science and Engineering, Kyoto University Japan

  11. Proceedings of the 19th International Conference on Ion Beam Modification of Materials (IBMM 2014)

    NASA Astrophysics Data System (ADS)

    Vantomme, André; Temst, Kristiaan

    2015-12-01

    It is our pleasure to present the proceedings of the 19th International Conference on Ion Beam Modification of Materials, which took place from September 14th until September 19th, 2014. The conference was held in the historic center of Leuven, a medieval city in the heart of Europe, a city where centuries-old culture meets frontier science and technology. Among other places, the conference brought us to the University Hall, which has been in use by the university since its foundation in 1425, to the Infirmerie of the Grand Beguinage and to the medieval city of Bruges, the latter two being Unesco World Heritage sites.

  12. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators

    PubMed Central

    Guterding, Daniel; Jeschke, Harald O.; Valentí, Roser

    2016-01-01

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions. PMID:27185665

  13. Spin Physics Results from Jefferson Lab Hall B and Hall C

    SciTech Connect

    M. Khandaker

    2004-04-01

    The spin physics program in Jefferson Lab's Hall B and Hall C concentrates on precision studies of the nucleon spin structure functions that can be extracted with inclusive and exclusive polarized scattering experiments in and above the resonance region at low to moderate Q{sup 2}. Results on proton and deuteron spin asymmetries, Lambda{sub 1} (W,Q{sup 2}) and Lambda{sub 2} (W,Q{sup 2}) from the Resonances' Spin Structure--RSS experiment in Hall C and the spin structure function g{sub 1} (x,Q{sup 2}) and its first moment Gamma{sub 1}(Q{sup 2}) from the CLAS EG1 Program in Hall B are presented.

  14. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators

    NASA Astrophysics Data System (ADS)

    Guterding, Daniel; Jeschke, Harald O.; Valentí, Roser

    2016-05-01

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions.

  15. The magneto-Hall difference and the planar extraordinary Hall balance

    NASA Astrophysics Data System (ADS)

    Zhang, S. L.; Hesjedal, T.

    2016-04-01

    The extraordinary Hall balance (EHB) is a general device concept that harnesses the net extraordinary Hall effect (EHE) arising from two independent magnetic layers, which are electrically in parallel. Different EHB behavior can be achieved by tuning the strength and type of interlayer coupling, i.e., ferromagnetic or antiferromagnetic of varying strength, allowing for logic and memory applications. The physics of the EHE in such a multilayered systems, especially the interface-induced effect, will be discussed. A discrepancy between the magnetization and the Hall effect, called the magneto-Hall difference (MHD) is found, which is not expected in conventional EHE systems. By taking advantage of the MHD effect, and by optimizing the materials structure, magnetoresistance ratios in excess of 40,000% can be achieved at room-temperature. We present a new design, the planar EHB, which has the potential to achieve significantly larger magnetoresistance ratios.

  16. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators.

    PubMed

    Guterding, Daniel; Jeschke, Harald O; Valentí, Roser

    2016-05-17

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions.

  17. From the Bricks to the Hall

    ERIC Educational Resources Information Center

    Torres, Mellie

    2009-01-01

    Situating herself on the cusp between life in her hometown of Newark, New Jersey, and her new world at Seton Hall University, Mellie Torres describes the painful awareness of a growing distance between herself, as the first to go to college, and her family. In so doing, she reveals the inherent losses of leaving home and the painful contrast…

  18. Residence Hall Furnishings Top 20 List.

    ERIC Educational Resources Information Center

    Tampke, Dale

    1999-01-01

    Provides advice on how to best meet the furniture needs of student residents now and in the future to ensure their privacy and value from the residence hall experience. Twenty tips are highlighted that include considering fire safety, upholstering, lifecycle costs, input from stakeholders, the Americans with Disabilities Act, comfort, lighting,…

  19. Soaring Food Prices Squeeze Dining Halls

    ERIC Educational Resources Information Center

    Hermes, JJ

    2008-01-01

    This article reports that students are likely to see a sharp increase in the cost of on-campus meal plans this fall, as rising food prices have sent some college food-service operations into deficits and have forced many to get creative with their fixed budgets. As the cost of food has soared, many dining halls have focused more on reducing…

  20. Moderate positive spin Hall angle in uranium

    SciTech Connect

    Singh, Simranjeet; Anguera, Marta; Barco, Enrique del E-mail: cwmsch@rit.edu; Springell, Ross; Miller, Casey W. E-mail: cwmsch@rit.edu

    2015-12-07

    We report measurements of spin pumping and the inverse spin Hall effect in Ni{sub 80}Fe{sub 20}/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni{sub 80}Fe{sub 20} (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 10{sup 19} m{sup −2} and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.

  1. A Small Modular Laboratory Hall Effect Thruster

    NASA Astrophysics Data System (ADS)

    Lee, Ty Davis

    Electric propulsion technologies promise to revolutionize access to space, opening the door for mission concepts unfeasible by traditional propulsion methods alone. The Hall effect thruster is a relatively high thrust, moderate specific impulse electric propulsion device that belongs to the class of electrostatic thrusters. Hall effect thrusters benefit from an extensive flight history, and offer significant performance and cost advantages when compared to other forms of electric propulsion. Ongoing research on these devices includes the investigation of mechanisms that tend to decrease overall thruster efficiency, as well as the development of new techniques to extend operational lifetimes. This thesis is primarily concerned with the design and construction of a Small Modular Laboratory Hall Effect Thruster (SMLHET), and its operation on argon propellant gas. Particular attention was addressed at low-cost, modular design principles, that would facilitate simple replacement and modification of key thruster parts such as the magnetic circuit and discharge channel. This capability is intended to facilitate future studies of device physics such as anomalous electron transport and magnetic shielding of the channel walls, that have an impact on thruster performance and life. Preliminary results demonstrate SMLHET running on argon in a manner characteristic of Hall effect thrusters, additionally a power balance method was utilized to estimate thruster performance. It is expected that future thruster studies utilizing heavier though more expensive gases like xenon or krypton, will observe increased efficiency and stability.

  2. FORT HALL SOURCE APPORTIONMENT STUDY (FINAL REPORT)

    EPA Science Inventory

    Air quality monitoring on the Fort Hall Indian Reservation has revealed numerous exceedances of the National Ambient Air Quality Standard (NAAQS) for 24-h averaged PM10 mass. Wind-directional analysis coupled with PM10 measurements have identified the FMC elemental phosphorus p...

  3. An Environmental Redesign Program for Residence Halls

    ERIC Educational Resources Information Center

    Daher, Douglas M.; And Others

    1977-01-01

    The Resident Environment Adaptation Program (REAP) is a five-stage service designed to enable students to heighten the match between their needs and their residence hall environment. In addition to a description of the program, the article includes pilot project conclusions and further recommendations for development. (Author)

  4. Large Spin Hall Angle in Vanadium Film

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Fan, Xin; Wang, Wenrui; Xie, Yunsong; Warsi, Muhammad A.; Wu, Jun; Chen, Yunpeng; Lorenz, Virginia O.; Xiao, John Q.

    We report the large spin Hall angle observed in Vanadium film with small grain size and distorted lattice parameter. The spin Hall angle is quantified by measuring current-induced spin-orbit torque in V/CoFeB bilayer using optical spin torque magnetometer based on polar magneto-optical Kerr effect (MOKE). The spin Hall angle as large as θSH = -0.071 has been observed in V/CoFeB bilayer Structural analysis, using X-ray diffraction (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), confirms films grown at room temperature have very small grain size and enlarged lattice parameter. The Vanadium films with distorted crystal structure also have high resistivity (>200 μΩ cm) and long spin diffusion length (~16.3 nm) measured via spin pumping experiment. This finding of spin Hall effect enhancement in more disordered structure will provide insights for understanding and exploiting materials with strong spin orbit interaction, especially in light 3d transition metals which promise long spin diffusion length.

  5. Town Hall on AGU Publishing Practices

    NASA Astrophysics Data System (ADS)

    Forlini, Victoria

    2013-01-01

    Representatives from AGU's leadership and Wiley fielded questions at a town hall during Fall Meeting that ranged from the pricing of AGU's digital library to the fate of AGU books to the role of the governance structure in approving the AGU-Wiley publications partnership.

  6. Fractional Quantization of the Hall Effect

    DOE R&D Accomplishments Database

    Laughlin, R. B.

    1984-02-27

    The Fractional Quantum Hall Effect is caused by the condensation of a two-dimensional electron gas in a strong magnetic field into a new type of macroscopic ground state, the elementary excitations of which are fermions of charge 1/m, where m is an odd integer. A mathematical description is presented.

  7. June 1992 Hall B collaboration meeting

    SciTech Connect

    Dennis, Lawrence

    1992-06-01

    The Hall B collaboration meeting at the CEBAF 1992 Summer Workshop consisted of technical and physics working group meetings, a special beam line devices working group meeting the first meeting of the membership committee, a technical representatives meeting and a full collaboration meeting. Highlights of these meetings are presented in this report.

  8. Hall Effect Thruster Ground Testing Challenges

    DTIC Science & Technology

    2009-08-18

    high purity propellent to eliminate the risk of oxidation poisoning the thermionically emitting electron/neutralizer source drive the entire Hall effect...Mason, L., Jankovsky, R., Snyder, J. S., Malone , S., Haas, J., and Gallimore, A. D., “Spacecraft Interaction Test Results for the High Performance

  9. College of Architecture Addition, Burchard Hall.

    ERIC Educational Resources Information Center

    Design Cost Data, 2001

    2001-01-01

    Describes the architectural design, costs, general description, and square footage data for the College of Architecture Addition, Burchard Hall in Blacksburg, Virginia. A floor plan and photos are included along with a list of manufacturers and suppliers used for the project. (GR)

  10. Engaging City Hall: Children as Citizens

    ERIC Educational Resources Information Center

    Krechevsky, Mara; Mardell, Ben; Romans, Angela N.

    2014-01-01

    In this article, the authors suggest that current notions of advocacy in early childhood education should be expanded to include a view of young children as citizens. The authors ground their discussion in a how-to book project in Providence, Rhode Island, consider different concepts of children and citizenship, share commentary from City Hall and…

  11. Air Temperature in the Undulator Hall

    SciTech Connect

    Not Available

    2010-12-07

    Various analyses have been performed recently to estimate the performance of the air conditioning (HVAC) system planned for the Undulator Hall. This reports summarizes the results and provides an upgrade plan to be used if new requirements are needed in the future. The estimates predict that with the planned loads the tunnel air temperature will be well within the allowed tolerance during normal operation.

  12. High Tech Images. San Bernardino City Hall

    ERIC Educational Resources Information Center

    McCoy, Esther

    1974-01-01

    A part of San Bernardino's larger redevelopment plan, the new City Hall has helped revitalize the downtown core. The solar bronze glass-surfaced structure, called a 6-story street, is the shape of the street which was closed to form the site. (Author/MF)

  13. PREFACE: Eucas '09: The 9th European Conference on Applied Superconductivity (Dresden, Germany, 13-17 September 2009)

    NASA Astrophysics Data System (ADS)

    Schultz, Ludwig; Holzapfel, Bernhard

    2010-04-01

    During the 9th European Conference on Applied Superconductivity 6 plenary, 22 invited, 206 oral and 429 poster contributions were presented on recent developments in the field of applied superconductivity. This issue of Journal of Physics: Conference Series contains all contributed papers that were accepted for the Conference Proceedings. The Dresden EUCAS conference with 712 participants from 43 countries continued the tradition of preceding EUCAS conferences of combining basic superconductivity research contributions with the discussion of recent material advances and new developments in large scale and electronic applications. In Dresden, contributions on the recently discovered Fe based superconductors were presented for the first time during a EUCAS conference and their potential for applications was intensively discussed. Finally we want to acknowledge the help of the International Advisory and National Committees in setting up the scientific program and especially we would like to express our gratitude to all members of the Local Organization Committee. Their enthusiastic and well organized work made this Dresden EUCAS conference a memorable event for all participants. Last but not least we are very grateful to W. Goldacker , S. Haindl, J. Hänisch, R. Hühne, M. Noe, P. Seidel and M. Siegel for their extraordinary help during the proceedings review process. Bernhard Holzapfel Ludwig Schultz Conference Chairmen The IW-SMI 2010 Organizing Committee: Masato Okada (University of Tokyo) Yoshiyuki Kabashima, General Chair (Tokyo Institute of Technology) Shin Ishii (Kyoto University) Jun-ichi Inoue, Publications Chair (Hokkaido University) Kazuyuki Tanaka (Tohoku University) Toshiyuki Tanaka, Vice-General Chair (Kyoto University)

  14. Topological honeycomb magnon Hall effect: A calculation of thermal Hall conductivity of magnetic spin excitations

    NASA Astrophysics Data System (ADS)

    Owerre, S. A.

    2016-07-01

    Quite recently, the magnon Hall effect of spin excitations has been observed experimentally on the kagome and pyrochlore lattices. The thermal Hall conductivity κxy changes sign as a function of magnetic field or temperature on the kagome lattice, and κxy changes sign upon reversing the sign of the magnetic field on the pyrochlore lattice. Motivated by these recent exciting experimental observations, we theoretically propose a simple realization of the magnon Hall effect in a two-band model on the honeycomb lattice. The magnon Hall effect of spin excitations arises in the usual way via the breaking of inversion symmetry of the lattice, however, by a next-nearest-neighbour Dzyaloshinsky-Moriya interaction. We find that κxy has a fixed sign for all parameter regimes considered. These results are in contrast to the Lieb, kagome, and pyrochlore lattices. We further show that the low-temperature dependence on the magnon Hall conductivity follows a T2 law, as opposed to the kagome and pyrochlore lattices. These results suggest an experimental procedure to measure thermal Hall conductivity within a class of 2D honeycomb quantum magnets and ultracold atoms trapped in a honeycomb optical lattice.

  15. Environmental manipulation affects depressive-like behaviours in female Wistar-Kyoto rats.

    PubMed

    Mileva, Guergana R; Bielajew, Catherine

    2015-10-15

    While the efficacy of pharmacological interventions to treat depression has been well-studied in animal models, much less work has been done to shed light on how changes in the immediate environment can impact behaviour. Furthermore, most studies have focused on male rodents despite the prevalence of mood disorders in women. In this study, 36 Wistar Kyoto (validated animal model of depression) and 36 Wistar (control) female rats were used to examine the effects of environmental manipulation on depressive- and anxiety-like behaviours. Animals were assigned to one of three groups: standard (3 rats/cage), enriched (6 rats/cage plus physical enrichment), and isolation (1 rat/cage) housing. The elevated plus maze (EPM) and forced swim test (FST) were conducted prior to, and four weeks after environmental assignment to measure anxiety-like and depressive-like behaviours, respectively. Sucrose preference assessed anhedonia both before and after environmental assignment. Weight was measured every week to monitor weight-gain over time. Post-environment sucrose preference was significantly increased in animals in enriched housing as compared to those in isolated housing in both strains. While there were significant differences between strains in measures of open arm duration in the EPM and immobility in the FST, there appeared to be no differences between environmental groups. The results of this study highlight the importance of environmental factors in the expression of anhedonia. Enrichment appears to reduce anhedonia while isolation increases anhedonia. These effects should be studied further to assess whether longer periods of social and physical enrichment alleviate other symptoms of depression.

  16. The first back-side illuminated types of Kyoto's X-ray astronomy SOIPIX

    NASA Astrophysics Data System (ADS)

    Itou, Makoto; Tsuru, Takeshi Go; Tanaka, Takaaki; Takeda, Ayaki; Matsumura, Hideaki; Ohmura, Shunichi; Uchida, Hiroyuki; Nakashima, Shinya; Arai, Yasuo; Kurachi, Ikuo; Mori, Koji; Takenaka, Ryota; Nishioka, Yusuke; Kohmura, Takayoshi; Tamasawa, Koki; Tindall, Craig

    2016-09-01

    We have been developing Kyoto's X-ray astronomy SOI pixel sensors, called "XRPIX", aiming to extend the frontiers of X-ray astronomy with the wide-band imaging spectroscopy in the 0.5-40 keV band. A dead layer on the X-ray incident surface should ideally be as thin as possible to achieve a high sensitivity below 1 keV, and the depletion layer is required to be thick enough to detect 40 keV X-rays. Thus, we have started developing fully-depleted back-side illuminated (BI) types of XRPIXs. This paper reports on our first two BI devices and their X-ray evaluation (2.6-12 keV). The device named "XRPIX2b-FZ-LA" successfully reaches a full depletion with a thickness of 500 μm. On the other hand, it has a dead layer with a thickness of 1.1-1.5 μm and struggles to achieve the requirement of 1.0 μm. The other device named "XRPIX2b-CZ-PZ", which is applied with a thin Si sensor-layer and an improved back-side process, is found to satisfy the requirement with its thickness of 0.9-1.0 μm, including Al optical blocking filter of 0.2 μm, although the Si sensor-layer is rather thin with 62 μm. We also describe in this paper the X-ray calibration system that we have built for the X-ray evaluation of XRPIXs.

  17. Conference Abstracts: AEDS '82.

    ERIC Educational Resources Information Center

    Journal of Computers in Mathematics and Science Teaching, 1982

    1982-01-01

    Abstracts from nine selected papers presented at the 1982 Association for Educational Data Systems (AEDS) conference are provided. Copies of conference proceedings may be obtained for fifteen dollars from the Association. (MP)

  18. Plasma relaxation and topological aspects in Hall magnetohydrodynamics

    SciTech Connect

    Shivamoggi, B. K.

    2012-07-15

    Parker's formulation of isotopological plasma relaxation process in magnetohydrodynamics (MHD) is extended to Hall MHD. The torsion coefficient {alpha} in the Hall MHD Beltrami condition turns out now to be proportional to the potential vorticity. The Hall MHD Beltrami condition becomes equivalent to the potential vorticity conservation equation in two-dimensional (2D) hydrodynamics if the Hall MHD Lagrange multiplier {beta} is taken to be proportional to the potential vorticity as well. The winding pattern of the magnetic field lines in Hall MHD then appears to evolve in the same way as potential vorticity lines in 2D hydrodynamics.

  19. The General Conference Mennonites.

    ERIC Educational Resources Information Center

    Ediger, Marlow

    General Conference Mennonites and Old Order Amish are compared and contrasted in the areas of physical appearance, religious beliefs, formal education, methods of farming, and home settings. General Conference Mennonites and Amish differ in physical appearance and especially in dress. The General Conference Mennonite men and women dress the same…

  20. EDITORIAL: Conference program

    NASA Astrophysics Data System (ADS)

    2006-04-01

    Some of the papers and talks given at the conference have not been published in this volume of Journal of Physics: Conference Series. The attached PDF file lists the full conference program and indicates (with an asterisk) those papers or talks which are not present in this volume.

  1. Youth Conference Handbook.

    ERIC Educational Resources Information Center

    Brown, Brenda H.

    This handbook is designed to provide practical aid to those who have charge of the planning and organization of a youth conference, Defined as a conference to provide practical information as well as information about possible responsibilities, risks, and consequences of actions, related to the chosen conference topic. Suggestions are given for…

  2. Parent Conferences. Beginnings Workshop.

    ERIC Educational Resources Information Center

    Duffy, Roslyn; And Others

    1997-01-01

    Presents six workshop sessions on parent conferences: (1) "Parents' Perspectives on Conferencing" (R. Duffy); (2) "Three Way Conferences" (G. Zeller); (3) "Conferencing with Parents of Infants" (K. Albrecht); (4) "Conferencing with Parents of School-Agers" (L. G. Miller); (5) "Cross Cultural Conferences" (J. Gonzalez-Mena); and (6) "Working with…

  3. A Hall effect angle detector for solid-state NMR.

    PubMed

    Mamone, Salvatore; Dorsch, André; Johannessen, Ole G; Naik, Manoj V; Madhu, P K; Levitt, Malcolm H

    2008-01-01

    We describe a new method for independent monitoring of the angle between the spinning axis and the magnetic field in solid-state NMR. A Hall effect magnetic flux sensor is fixed to the spinning housing, so that a change in the stator orientation leads to a change in the angle between the Hall plane and the static magnetic field. This leads to a change in the Hall voltage generated by the sensor when an electric current is passed through it. The Hall voltage may be measured externally by a precision voltmeter, allowing the spinning angle to be measured non-mechanically and independent of the NMR experiment. If the Hall sensor is mounted so that the magnetic field is approximately parallel to the Hall plane, the Hall voltage becomes highly sensitive to the stator orientation. The current angular accuracy is around 10 millidegrees. The precautions needed to achieve higher angular accuracy are described.

  4. Diagnostics Systems for Permanent Hall Thrusters Development

    NASA Astrophysics Data System (ADS)

    Ferreira, Jose Leonardo; Soares Ferreira, Ivan; Santos, Jean; Miranda, Rodrigo; Possa, M. Gabriela

    This work describes the development of Permanent Magnet Hall Effect Plasma Thruster (PHALL) and its diagnostic systems at The Plasma Physics Laboratory of University of Brasilia. The project consists on the construction and characterization of plasma propulsion engines based on the Hall Effect. Electric thrusters have been employed in over 220 successful space missions. Two types stand out: the Hall-Effect Thruster (HET) and the Gridded Ion Engine (GIE). The first, which we deal with in this project, has the advantage of greater simplicity of operation, a smaller weight for the propulsion subsystem and a longer shelf life. It can operate in two configurations: magnetic layer and anode layer, the difference between the two lying in the positioning of the anode inside the plasma channel. A Hall-Effect Thruster-HET is a type of plasma thruster in which the propellant gas is ionized and accelerated by a magneto hydrodynamic effect combined with electrostatic ion acceleration. So the essential operating principle of the HET is that it uses a J x B force and an electrostatic potential to accelerate ions up to high speeds. In a HET, the attractive negative charge is provided by electrons at the open end of the Thruster instead of a grid, as in the case of the electrostatic ion thrusters. A strong radial magnetic field is used to hold the electrons in place, with the combination of the magnetic field and the electrostatic potential force generating a fast circulating electron current, the Hall current, around the axis of the Thruster, mainly composed by drifting electrons in an ion plasma background. Only a slow axial drift towards the anode occurs. The main attractive features of the Hall-Effect Thruster are its simple design and operating principles. Most of the Hall-Effect Thrusters use electromagnet coils to produce the main magnetic field responsible for plasma generation and acceleration. In this paper we present a different new concept, a Permanent Magnet Hall

  5. Judy Estes Hall (1940-2015).

    PubMed

    Sammons, Morgan T; Boucher, Andrew

    2016-01-01

    Presents an obituary for Judy Estes Hall, who passed away on November 24, 2015. Hall served as the Executive Officer of the National Register of Health Service Psychologists until her retirement in 2013. She is a recognized expert in the development of education and training standards for the profession of psychology, she also made significant contributions in the field of international psychology, where she was a renowned expert in cross-national credentialing and an advocate for commonality in licensing standards. She was the coauthor of one edited volume and author of more than 60 journal articles, book chapters, and professional publications. A passionate advocate for the advancement of women in psychology, a devoted mother and grandmother, a connoisseur of wine and international traveler extraordinaire, she touched the personal and professional lives of many. (PsycINFO Database Record

  6. Precise Quantization of Anomalous Hall Effect

    NASA Astrophysics Data System (ADS)

    Bestwick, Andrew

    In the quantum anomalous Hall effect, electron transport in a magnetically-doped topological insulator takes place through chiral, dissipationless edge channels. In this talk, we discuss the behavior of a nearly ideal implementations of the effect in which the Hall resistance is within a part per 10,000 of its quantized value and the longitudinal resistivity can reach below 1 Ω per square. Nearly all Cr-doped topological insulator samples demonstrate extreme temperature dependence that is well-modeled by a small effective gap, allowing control over quantization with an unexpected magnetocaloric effect. We also discuss measurements of new device geometries and non-local resistances that identify the sources of dissipation that limit the effect. (Now at Rigetti Computing).

  7. Induced radioisotopes in a linac treatment hall.

    PubMed

    Vega-Carrillo, Héctor René; de Leon-Martinez, Héctor Asael; Rivera-Perez, Esteban; Luis Benites-Rengifo, Jorge; Gallego, Eduardo; Lorente, Alfredo

    2015-08-01

    When linacs operate above 8MV an undesirable neutron field is produced whose spectrum has three main components: the direct spectrum due to those neutrons leaking out from the linac head, the scattered spectrum due to neutrons produced in the head that collides with the nuclei in the head losing energy and the third spectrum due to room-return effect. The third category of spectrum has mainly epithermal and thermal neutrons being constant at any location in the treatment hall. These neutrons induce activation in the linac components, the concrete walls and in the patient body. Here the induced radioisotopes have been identified in concrete samples located in the hall and in one of the wedges. The identification has been carried out using a gamma-ray spectrometer.

  8. Current Distributions in Quantum Hall Effect Devices

    PubMed Central

    Cage, M. E.

    1997-01-01

    This paper addresses the question of how current is distributed within quantum Hall effect devices. Three types of flow patterns most often mentioned in the literature are considered. They are: (1) skipping orbits along the device periphery (which arise from elastic collisions off hard-walled potentials); (2) narrow conducting channels along the device sides (which are presumed to be generated from confining potentials); and (3) currents distributed throughout the device (which are assumed to arise from a combination of confining and charge-redistribution potentials). The major conclusions are that skipping orbits do not occur in quantum Hall effect devices, and that nearly all of the externally applied current is located within the device interior rather than along the device edges. PMID:27805115

  9. Fast Camera Imaging of Hall Thruster Ignition

    SciTech Connect

    C.L. Ellison, Y. Raitses and N.J. Fisch

    2011-02-24

    Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 μs. The cathode introduces azimuthal asymmetry, which persists for about 30 μs into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correction and drag compensation. The advantage of plasma thrusters over conventional chemical thrusters is that the exhaust energies are not limited by chemical energy to about an electron volt. For xenon Hall thrusters, the ion exhaust velocity can be 15-20 km/s, compared to 5 km/s for a typical chemical thruster

  10. Three halls for music performance in Chile

    NASA Astrophysics Data System (ADS)

    Delannoy, Jaime; Heuffemann, Carolina; Ramirez, Daniel; Galvez, Fernando

    2002-11-01

    The primary purpose of this work was to investigate about the present acoustic conditions of used architectonic spaces in Santiago of Chile for orchestras of classic music performance. The studied halls were three: Aula Magna Universidad de Santiago, Teatro Municipal de Nunoa, and Teatro Baquedano. The used methodology was based on studies made by L. Beranek, M. Barron, among others, in concert halls worldwide. As it guides, for the measurement procedure, physical parameters RT, EDT, C50, C80, LF, BR, G, U50 were evaluated according to norm ISO 3382. On the other hand, it has been defined, to proposal way, a questionnaire of subjective valuation directed to musicians, specialized conductors, and listeners.

  11. Supercurrent in the quantum Hall regime

    NASA Astrophysics Data System (ADS)

    Wei, Ming-Tso; Amet, François; Ke, Chung-Ting; Borzenets, Ivan; Wang, Jiyingmei; Watanabe, Keji; Taniguchi, Takashi; Deacon, Russell; Yamamoto, Michihisa; Bomze, Yuriy; Tarucha, Seigo; Finkelstein, Gleb

    Combining superconductivity and the quantum Hall (QH) effect is a promising route for creating new types of topological excitations. Despite this potential, signatures of superconductivity in the quantum Hall regime remain scarce, and a superconducting current through a QH weak link has so far eluded experimental observation. Here we demonstrate the existence of a novel type of Josephson coupling through a QH region at magnetic fields as high as 2 Tesla. The supercurrent is mediated by states encompassing QH edge channels, which are flowing on opposite sides of the sample. The edges are coupled together by the hybrid electron-hole modes at the interfaces between the QH region and the superconducting contacts. These chiral modes, which share some features with Majorana modes, are formed when electron and hole edge states are mixed by the superconductor.

  12. Developments in the quantum Hall effect.

    PubMed

    von Klitzing, Klaus

    2005-09-15

    The most important applications of the quantum Hall effect (QHE) are in the field of metrology. The observed quantization of the resistance is primarily used for the reproduction of the SI unit ohm, but is also important for high precision measurements of both the fine structure constant and the Planck constant. Some current QHE research areas include the analysis of new electron-electron correlation phenomena and the development of a more complete microscopic picture of this quantum effect. Recently, scanning force microscopy (SFM) of the potential distribution in QHE devices has been used to enhance the microscopic understanding of current flow in quantum Hall systems. This confirms the importance of the theoretically predicted stripes of compressible and incompressible electronic states close to the boundary of the QHE devices.

  13. Anisotropic Spin Hall Effect from First Principles

    NASA Astrophysics Data System (ADS)

    Freimuth, Frank; Blügel, Stefan; Mokrousov, Yuriy

    2011-03-01

    We present first principles calculations of the intrinsic non-dissipative spin Hall conductivity (SHC) for 3 d , 4 d and 5 d transition metals focusing in particular on the anisotropy of the SHC in nonmagnetic hcp metals and in antiferromagnetic Cr. For the metals of this study we generally find large anisotropies. We derive the general relation between the SHC vector and the direction of spin-polarization and discuss its consequences for hcp metals. Especially, it is predicted that for systems where the SHC changes sign due to the anisotropy the spin Hall effect may be tuned such that the spin polarization is parallel either to the electric field or to the spin current. Additionally, we describe our computational method [2,3] emphasizing the Wannier interpolation technique and the definition of the conserved spin current. This work is supported by the DFG Project MO 1731/3-1 and HGF-YIG grant VH-NG-513.

  14. Inhaled environmental combustion particles cause myocardial injury in the Wistar Kyoto rat.

    PubMed

    Kodavanti, Urmila P; Moyer, Carolyn F; Ledbetter, Allen D; Schladweiler, Mette C; Costa, Daniel L; Hauser, Russ; Christiani, David C; Nyska, Abraham

    2003-02-01

    Epidemiologists have associated particulate matter (PM) air pollution with cardiovascular morbidity and premature mortality worldwide. However, experimental evidence demonstrating causality and pathogenesis of particulate matter (PM)-induced cardiovascular damage has been insufficient. We hypothesized that protracted, repeated inhalation by rats of oil combustion-derived, fugitive emission PM (EPM), similar in metal composition to selected sources of urban air PM, causes exposure duration- and dose-dependent myocardial injury in susceptible rat strains. Zinc was the only primary water-leachable/bioavailable element of this EPM. Male Sprague-Dawley (SD), Wistar Kyoto (WKY), and spontaneously hypertensive (SH) rats were exposed nose-only to EPM (2, 5, or 10 mg/m(3), 6 h/day for 4 consecutive days or 10 mg/m(3), 6 h/day, 1 day/week for 4 or 16 consecutive weeks). Two days following the last EPM exposure, cardiac and pulmonary tissues were examined histologically. The results showed that particle-laden alveolar macrophages were the only pulmonary lesions observed in all three rat strains. However, WKY rats exposed to EPM (10 mg/m(3) 6 h/day, 1 day/week for 16 weeks) demonstrated cardiac lesions with inflammation and degeneration. To further characterize the nature of EPM-associated lesions, more rigorous histopathological and histochemical techniques were employed for WKY and SD rats. We examined the hearts for myocardial degeneration, inflammation, fibrosis, calcium deposits, apoptosis, and the presence of mast cells. Decreased numbers of granulated mast cells, and multifocal myocardial degeneration, chronic-active inflammation, and fibrosis were present in 5 of 6 WKY rats exposed to EPM for 16 weeks. None of these lesions were present in WKY exposed to clean air. EPM-related cardiac lesions were indistinguishable from air-exposed controls in SD and SH rats. This study demonstrates that long-term inhalation exposures to environmentally relevant PM containing

  15. SERVIR Town Hall - Connecting Space to Village

    NASA Technical Reports Server (NTRS)

    Limaye, Ashutosh S.; Searby, Nancy D.; Irwin, Daniel; Albers, Cerese

    2013-01-01

    SERVIR, a joint NASA-USAID project, strives to improve environmental decision making through the use of Earth observations, models, and geospatial technology innovations. SERVIR connects these assets with the needs of end users in Mesoamerica, East Africa, and Hindu Kush-Himalaya regions. This Town Hall meeting will engage the AGU community by exploring examples of connecting Space to Village with SERVIR science applications.

  16. Mode Transitions in Hall Effect Thrusters

    DTIC Science & Technology

    2013-07-01

    Astronautics Mode Transitions in Hall Effect Thrusters Michael J. Sekerak 1 , Benjamin W. Longmier 2 and Alec D. Gallimore 3 University of Michigan...nude Faraday probe, retarding potential analyzer and cylindrical Langmuir prove, Brown showed the transition from “low-current” to “high-current...thank two former PEPL students: Dr. Robert Lobbia for development of the HDLP; and Dr. Michael McDonald for development of the FastCam Analysis

  17. Thermal Characterization of a Hall Effect Thruster

    DTIC Science & Technology

    2008-03-01

    Material Curie Temperature Iron 770 °C Nickel 358 °C Cobalt 1130 °C Gadolinium 20 °C Terfenol 380-430 °C Alnico 850 °C Hard Ferrites 400-700...C Barium Ferrite 450 °C Hall Effect thrusters generally use iron magnets with a Curie temperature of 770 °C. Decreasing the magnetic strength

  18. The Hall D Physics Program at JLab

    SciTech Connect

    Leckey, John P.

    2012-09-01

    GlueX is one of the flagship experiments of the 12 GeV era at the Thomas Jefferson National Accelerator Facility (JLab). The energy of the electron accelerator at JLab is presently undergoing an upgrade from 6 GeV to 12 GeV and a 4th experimental hall (Hall D) is being added. The GlueX experimental apparatus consists of a tagged coherent bremsstrahlung photon beam incident on a liquid hydrogen target. The photoproduced mesons, which are created inside of a 2.2 T solenoid, will then pass through a pair of drift chambers and eventually deposit their energy into either of two calorimeters, depending on their respective angles. GlueX will attempt to map out the light meson spectrum and search for meson-gluon hybrids to better understand the confinement of quarks and gluons in quantum chromodynamics (QCD). There is little data on the photoproduction of light mesons and the GlueX experiment will exceed the current photoproduction data by several orders of magnitude in the first year alone. Photoproduction is specifically well suited to search for meson-gluon hybrids because in the flux tube model the production cross-sections are higher for meson-gluon hybrids from photons, with the spins of the virtual quark-antiquark pair aligned, than from other sources such as pions, with the spins of the quark-antiquark pair anti-aligned. There are also other Hall D experiments proposed to look for physics beyond the Standard Model by studying Eta rare or forbidden decay channels such as eta to two neutral pions. The 12 GeV upgrade of the JLab accelerator and the complete physics program of Hall D will be presented.

  19. High temperature Hall-effect apparatus

    NASA Technical Reports Server (NTRS)

    Wood, C.; Lockwood, A.; Chmielewski, A.; Parker, J.; Zoltan, A.

    1984-01-01

    A high-temperature Hall-effect apparatus is described which allows measurements up to temperatures greater than 1200 K using the van der Pauw method. The apparatus was designed for measurements on refractory materials having high charge carrier concentrations and generally low mobilities. Pressure contacts are applied to the samples. Consequently, special contacting methods, peculiar to a specific sample material, are not required. The apparatus has been semiautomated to facilitate measurements. Results are presented on n- and p-type silicon.

  20. Electron-wall Interaction in Hall Thrusters

    SciTech Connect

    Y. Raitses; D. Staack; M. Keidar; N.J. Fisch

    2005-02-11

    Electron-wall interaction effects in Hall thrusters are studied through measurements of the plasma response to variations of the thruster channel width and the discharge voltage. The discharge voltage threshold is shown to separate two thruster regimes. Below this threshold, the electron energy gain is constant in the acceleration region and therefore, secondary electron emission (SEE) from the channel walls is insufficient to enhance electron energy losses at the channel walls. Above this voltage threshold, the maximum electron temperature saturates.

  1. Low-Voltage Hall Thruster Mode Transitions

    DTIC Science & Technology

    2014-06-01

    Sci. Instrum. 81, 083504 (2010). 19 Brown, D. L., “ Electric Propulsion Test and Evaluation Methodologies for Plasma in the Environment of Space and... Propulsion Laboratory (JPL) and University of Michigan (UM) to serve as a standardized test -bed for Hall thruster physics research, and is based on...150-A AMREL HPS1000-150 DC power supply in-line with a low-pass filter. The filter was located outside the facility near the electrical feed-through

  2. Numerical Modeling of the Hall Thruster Discharge

    DTIC Science & Technology

    2005-04-01

    Studies of the near anode region (Docs. 6 and 7) Attached documents 1. F. Parra, E. Ahedo, M. Martínez-Sánchez, and J.M. Fife...Ahedo, ‘On the near anode region of the Hall thruster discharge’, paper AIAA 2004-3774, American Institute of Aeronautics and Astronautics, Washington...inside the thruster chamber. The resulting document 5 completes works initiated in previous projects. Finally, the analysis of the near-anode region

  3. Generic superweak chaos induced by Hall effect.

    PubMed

    Ben-Harush, Moti; Dana, Itzhack

    2016-05-01

    We introduce and study the "kicked Hall system" (KHS), i.e., charged particles periodically kicked in the presence of uniform magnetic (B) and electric (E) fields that are perpendicular to each other and to the kicking direction. We show that for resonant values of B and E and in the weak-chaos regime of sufficiently small nonintegrability parameter κ (the kicking strength), there exists a generic family of periodic kicking potentials for which the Hall effect from B and E significantly suppresses the weak chaos, replacing it by "superweak" chaos (SWC). This means that the system behaves as if the kicking strength were κ^{2} rather than κ. For E=0, SWC is known to be a classical fingerprint of quantum antiresonance, but it occurs under much less generic conditions, in particular only for very special kicking potentials. Manifestations of SWC are a decrease in the instability of periodic orbits and a narrowing of the chaotic layers, relative to the ordinary weak-chaos case. Also, for global SWC, taking place on an infinite "stochastic web" in phase space, the chaotic diffusion on the web is much slower than the weak-chaos one. Thus, the Hall effect can be relatively stabilizing for small κ. In some special cases, the effect is shown to cause ballistic motion for almost all parameter values. The generic global SWC on stochastic webs in the KHS appears to be the two-dimensional closest analog to the Arnol'd web in higher dimensional systems.

  4. Quantum anomalous Hall effect in real materials

    NASA Astrophysics Data System (ADS)

    Zhang, Jiayong; Zhao, Bao; Zhou, Tong; Yang, Zhongqin

    2016-11-01

    Under a strong magnetic field, the quantum Hall (QH) effect can be observed in two-dimensional electronic gas systems. If the quantized Hall conductivity is acquired in a system without the need of an external magnetic field, then it will give rise to a new quantum state, the quantum anomalous Hall (QAH) state. The QAH state is a novel quantum state that is insulating in the bulk but exhibits unique conducting edge states topologically protected from backscattering and holds great potential for applications in low-power-consumption electronics. The realization of the QAH effect in real materials is of great significance. In this paper, we systematically review the theoretical proposals that have been brought forward to realize the QAH effect in various real material systems or structures, including magnetically doped topological insulators, graphene-based systems, silicene-based systems, two-dimensional organometallic frameworks, quantum wells, and functionalized Sb(111) monolayers, etc. Our paper can help our readers to quickly grasp the recent developments in this field. Project supported by the National Basic Research Program of China (Grant No. 2011CB921803), the National Natural Science Foundation of China (Grant No. 11574051), the Natural Science Foundation of Shanghai, China (Grant No. 14ZR1403400), and Fudan High-end Computing Center, China.

  5. Vibrational modes in the quantum Hall system

    NASA Astrophysics Data System (ADS)

    Wooten, Rachel; Yan, Bin; Daily, Kevin; Greene, Chris H.

    The hyperspherical adiabatic technique is more familiar to atomic and nuclear few-body systems, but can also be applied with high accuracy to the many-body quantum Hall problem. This technique reformulates the Schrödinger equation for N electrons into hyperspherical coordinates, which, after extracting the trivial center of mass, describes the system in terms of a single global size coordinate known as the hyperradius R, and 2 N - 3 remaining internal angular coordinates. The solutions are approximately separable in the hyperradial coordinate, and solutions in the system are found by treating the hyperradius as an adiabatic coordinate. The approximate separability of the wave functions in this coordinate suggests the presence of hyperradial vibrational modes which are not described in conventional theories. The vibrationally excited states share the internal geometry of their quantum Hall ground states, and their excitation frequencies may vary with the number of participating particles or the strength of the confinement. We plan to discuss the features of these vibrational modes and their possible detection in quantum Hall systems. NSF.

  6. 3D Hall MHD Reconnection Dynamics

    NASA Astrophysics Data System (ADS)

    Huba, J. D.; Rudakov, L.

    2002-05-01

    A 3D Hall MHD simulation code (VooDoo) has recently been developed at the Naval Research Laboratory. We present preliminary results of a fully 3D magnetic reconnection study using this code. The initial configuration of the plasma system is as follows. The ambient, reversed magnetic field is in the x-direction and is proportional to B0 tanh(y/Ly) where Ly is the scale length of the current sheet. Perturbation fields δ Bx and δ By are introduced to initiate the reconnection process. This initial configuration is similar to that used in the 2D GEM reconnection study. However, the perturbation fields are localized in the z-direction. We consider two cases: no guide field (Bz = 0) and a weak guide field (Bz = 0.1B0). We find that the reconnection process is not stationary in the z-direction but propagates in the B x ∇ n direction consistent with Hall drift physics. Hence, an asymmetric disruption of the current sheet ensues. The flow structure of the plasma in the vicinity of the X-point is complex. We find that the `neutral line' (i.e, along the z-direction) is not an ignorable coordinate and is not periodic in Hall MHD reconnection dynamics; two assumptions that are often made in reconnection studies. \\ Research supported by NASA and ONR

  7. Hall Effect Measured Using a Waveguide Tee

    NASA Astrophysics Data System (ADS)

    Coppock, Joyce; Anderson, James; Johnson, William

    2013-03-01

    We describe a simple microwave apparatus to measure the Hall effect in semiconductor wafers. The advantage of this technique is that it does not require contacts on the sample, unlike the Van der Pauw method.[1] Our method consists of placing the semiconductor wafer into a slot cut in an X-band waveguide tee and placing the tee in the center of an electromagnet. The next step is to inject power into two arms of the tee and to balance the output so that no power comes out of the third arm of the tee at zero magnetic field. Application of a nonzero magnetic field gives a Hall signal that is linear in the magnetic field and which reverses phase when the magnetic field is reversed. We use a network analyzer to measure the ratio of the Hall signal to the input power. This method yields the semiconductor mobility in the wafer, which we can compare for calibration purposes with mobility data from our Van der Pauw measurements. This talk presents data for silicon and germanium samples doped with boron or phosphorus. Preliminary measurements on doped III-V semiconductor samples will also be presented.

  8. Anode Fall Formation in a Hall Thruster

    SciTech Connect

    Leonid A. Dorf; Yevgeny F. Raitses; Artem N. Smirnov; Nathaniel J. Fisch

    2004-06-29

    As was reported in our previous work, accurate, nondisturbing near-anode measurements of the plasma density, electron temperature, and plasma potential performed with biased and emissive probes allowed the first experimental identification of both electron-repelling (negative anode fall) and electron-attracting (positive anode fall) anode sheaths in Hall thrusters. An interesting new phenomenon revealed by the probe measurements is that the anode fall changes from positive to negative upon removal of the dielectric coating, which appears on the anode surface during the course of Hall thruster operation. As reported in the present work, energy dispersion spectroscopy analysis of the chemical composition of the anode dielectric coating indicates that the coating layer consists essentially of an oxide of the anode material (stainless steel). However, it is still unclear how oxygen gets into the thruster channel. Most importantly, possible mechanisms of anode fall formation in a Hall thruster with a clean and a coated anodes are analyzed in this work; practical implication of understanding the general structure of the electron-attracting anode sheath in the case of a coated anode is also discussed.

  9. A non-invasive Hall current distribution measurement system for Hall Effect thrusters

    NASA Astrophysics Data System (ADS)

    Mullins, Carl Raymond

    A direct, accurate method to measure thrust produced by a Hall Effect thruster on orbit does not currently exist. The ability to calculate produced thrust will enable timely and precise maneuvering of spacecraft---a capability particularly important to satellite formation flying. The means to determine thrust directly is achievable by remotely measuring the magnetic field of the thruster and solving the inverse magnetostatic problem for the Hall current density distribution. For this thesis, the magnetic field was measured by employing an array of eight tunneling magnetoresistive (TMR) sensors capable of milligauss sensitivity when placed in a high background field. The array was positioned outside the channel of a 1.5 kW Colorado State University Hall thruster equipped with a center-mounted electride cathode. In this location, the static magnetic field is approximately 30 Gauss, which is within the linear operating range of the TMR sensors. Furthermore, the induced field at this distance is greater than tens of milligauss, which is within the sensitivity range of the TMR sensors. Due to the nature of the inverse problem, the induced-field measurements do not provide the Hall current density by a simple inversion; however, a Tikhonov regularization of the induced field along with a non-negativity constraint and a zero boundary condition provides current density distributions. Our system measures the sensor outputs at 2 MHz allowing the determination of the Hall current density distribution as a function of time. These data are shown in contour plots in sequential frames. The measured ratios between the average Hall current and the discharge current ranged from 0.1 to 10 over a range of operating conditions from 1.3 kW to 2.2 kW. The temporal inverse solution at 2.0 kW exhibited a breathing mode of 37 kHz, which was in agreement with temporal measurements of the discharge current.

  10. 10 CFR 501.32 - Conferences (other than prepetition conferences).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Conferences (other than prepetition conferences). 501.32... SANCTIONS Written Comments, Public Hearings and Conferences During Administrative Proceedings § 501.32 Conferences (other than prepetition conferences). (a) At any time following commencement of a...

  11. 47 CFR 1.248 - Prehearing conferences; hearing conferences.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Prehearing conferences; hearing conferences. 1... Hearing Proceedings Prehearing Procedures § 1.248 Prehearing conferences; hearing conferences. (a) The... to appear at a specified time and place for a conference prior to a hearing, or to submit...

  12. PREFACE: International Conference on High Pressure Science and Technology, Joint AIRAPT-22 & HPCJ-50

    NASA Astrophysics Data System (ADS)

    Viña, Luis; Tejedor, Carlos; Calleja, José M.

    2010-01-01

    The International Joint AIRAPT-22 & HPCJ-50 Conference was held in Odaiba, Tokyo, on 26-31 July 2009. About 480 scientists from 24 countries attended the conference and 464 papers, including 3 plenary lectures, 39 invited talks, and 156 oral presentations, were presented. It is my great pleasure to present this proceedings volume, which is based on the high quality scientific works presented at the conference. The International AIRAPT conference has been held every two years in various countries around the world since 1965, while High Pressure Conference of Japan (HPCJ) has been held annually since 1959 in various Japanese cities. Pressure is a fundamental parameter to control the property of matter. As a result, both AIRAPT and HPCJ have become highly multidisciplinary, and cover Physics, Chemistry, Materials Science, Earth and Planetary Sciences, Biosciences, Food Science, and Technology. Although each discipline has a unique target, they all have high-pressure research in common. This proceedings volume includes about 200 papers of state-of-the-art studies from numerous fields. I hope this proceedings volume provides excellent pieces of information in various fields to further advance high-pressure research. Conference logo Takehiko Yagi Conference Chairman Institute for Solid State Physics The University of Tokyo 7 December 2009 Conference photograph Participants at the conference venue, Tokyo International Exchange Center, Odaiba, Tokyo, Japan. Editor in Chief TAKEMURA Kenichi National Institute for Materials Science, Japan Editorial board Tadashi KONDO Osaka University, Japan Hitoshi MATSUKI The University of Tokushima, Japan Nobuyuki MATUBAYASI Kyoto University, Japan Yoshihisa MORI Okayama University of Science, Japan Osamu OHTAKA Osaka University, Japan Chihiro SEKINE Muroran Institute of Technology, Japan

  13. Basic Instrumentation for Hall A at Jefferson Jab

    SciTech Connect

    The Jefferson Lab Hall A Collaboration

    2003-07-01

    The instrumentation in Hall A at the JLab was designed to study electro- and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. A collaboration of approximately 50 institutions from all over the world has actively contributed and participated in the design, construction and commissioning of the Hall A instrumentation. The basic Hall A equipment is described herein.

  14. High-Field Fractional Quantum Hall Effect in Optical Lattices

    SciTech Connect

    Palmer, R.N.; Jaksch, D.

    2006-05-12

    We consider interacting bosonic atoms in an optical lattice subject to a large simulated magnetic field. We develop a model similar to a bilayer fractional quantum Hall system valid near simple rational numbers of magnetic flux quanta per lattice cell. Then we calculate its ground state, magnetic lengths, fractional fillings, and find unexpected sign changes in the Hall current. Finally we study methods for detecting these novel features via shot noise and Hall current measurements.

  15. Factors Affecting the Efficiency of Krypton Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Hofer, Richard R.; Peterson, Peter Y.; Jacobson, David T.; Manzella, David M.

    2004-01-01

    The krypton-fueled Hall thruster offers the possibility of high-specific impulse and long lifetime. NASA's series of Hall thrusters have demonstrated krypton efficiencies only 5 - 15% less than xenon. Larger thrusters have smaller differences in efficiency. Plasma measurements have demonstrated that efficiency is reduced due to a decrease in mass utilization. Current efforts are considering the implications of these results, and how design changes can be made to increase the efficiency of krypton Hall thrusters.

  16. Faster Hall-Effect Current-Measuring Circuit

    NASA Technical Reports Server (NTRS)

    Sullender, Craig C.; Johnson, Daniel D.; Walker, Daniel D.

    1993-01-01

    Current-measuring circuit operates on Hall-effect-sensing and magnetic-field-nulling principles similar to those described in article, "Nulling Hall-Effect Current-Measuring Circuit" (LEW-15023), but simpler and responds faster. Designed without feedback loop, and analog pulse-width-modulated output indicates measured current. Circuit measures current at frequency higher than bandwidth of its Hall-effect sensor.

  17. Size dependence of microscopic Hall sensor detection limits.

    PubMed

    Vervaeke, K; Simoen, E; Borghs, G; Moshchalkov, V V

    2009-07-01

    In this paper the magnetic field detection limits of microscopic Hall sensors are investigated as a function of their lateral size. Hall sensors fabricated from GaAs/AlGaAs heterostructures and silicon are experimentally investigated at different temperatures using Hall effect and noise spectrum measurements. At room temperature a clear size dependence of the detection limit is observed, whereas at low temperatures this dependence is found to disappear. The results are explained using the theory of noise in semiconductors.

  18. The impact of economic activity in Asturias on greenhouse gas emissions: consequences for environmental policy within the Kyoto Protocol framework.

    PubMed

    Argüelles, Margarita; Benavides, Carmen; Junquera, Beatriz

    2006-11-01

    Climate change is one of the major worldwide environmental concerns. It is especially the case in many developed countries, where the greenhouse gas emissions responsible for this change are mainly concentrated. For the first time, the Kyoto Protocol includes an international agreement for the reduction of the net emissions of these gases. To fulfil this agreement measures designed to reduce or limit current emissions have to be brought into force. Consequently, fears have arisen about possible consequences on competitiveness and future development of manufacturing activities and the need for support mechanisms for the affected sectors is obvious. In this paper, we carry out a study of the emissions of gases responsible for climate change in Asturias (Spain), a region with an important economic presence of sectors with intensive emissions of CO(2), the chief greenhouse gas. To be precise, in the first place, the volumes of direct emissions of the said gases in 1995 were calculated, showing that the sectors most affected by the Kyoto Protocol in Asturias are iron and steel and electricity production. Secondly, input-output analysis was applied to determine the direct and indirect emissions and the direct, indirect and induced emissions of the different production sectors, respectively. The results derived from the direct and indirect emissions analysis and their comparison with the results of the former allow us to reach some conclusions and environmental policy implications.

  19. Capping the cost of compliance with the Kyoto Protocol and recycling revenues into land-use projects.

    PubMed

    Schlamadinger, B; Obersteiner, M; Michaelowa, A; Grubb, M; Azar, C; Yamagata, Y; Goldberg, D; Read, P; Kirschbaum, M U; Fearnside, P M; Sugiyama, T; Rametsteiner, E; Böswald, K

    2001-07-14

    There is the concern among some countries that compliance costs with commitments under the Kyoto Protocol may be unacceptably high. There is also the concern that technical difficulties with the inclusion of land use, land-use change, and forestry activities in non-Annex I countries might lead to an effective exclusion of such activities from consideration under the Protocol. This paper is proposing a mechanism that addresses both these concerns. In essence, it is suggested that parties should be able to purchase fixed-price offset certificates if they feel they cannot achieve compliance through other means alone, such as by improved energy efficiency, increased use of renewable energy, or use of the flexible mechanisms in the Kyoto Protocol. These offset certificates would act as a price cap for the cost of compliance for any party to the Protocol. Revenues from purchase of the offset certificates would be directed to forest-based activities in non-Annex I countries such as forest protection that may carry multiple benefits including enhancing net carbon sequestration.

  20. MAGNETORESISTANCE AND HALL EFFECT IN SINGLE CRYSTALS OF ALUMINUM

    DTIC Science & Technology

    ALUMINUM, *SINGLE CRYSTALS, CRYSTALS, HALL EFFECT , IMPURITIES, LOW PRESSURE, MAGNETIC FIELDS, MAGNETIC PROPERTIES, PARTICLE TRAJECTORIES, ELECTRICAL RESISTANCE, SOLID STATE PHYSICS, SURFACE PROPERTIES.

  1. 25 Years quantum Hall effect: how it all came about

    NASA Astrophysics Data System (ADS)

    Landwehr, G.

    2003-12-01

    The quantum Hall effect (QHE) was discovered by Klaus von Klitzing in the spring of 1980. However, the plateaus in the Hall resistance of silicon metal oxide semiconductor devices which can be observed in high magnetic fields at low temperatures showed up several years earlier. The world wide research, which eventually culminated in the discovery, is briefly reviewed. The QHE was not predicted by theory, there were only approximate indications of quantization of the Hall resistance in whole fractions of h/ e2. The exceptional precision of the resistance values of the Hall plateau led very soon to a new resistance standard.

  2. double hung window details, hall window details, entrance door profiles ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    double hung window details, hall window details, entrance door profiles - Chopawamsic Recreational Demonstration Area - Cabin Camp 1, Help's Quarters, Prince William Forest Park, Triangle, Prince William County, VA

  3. Volumetric Hall effect tomography--a feasibility study.

    PubMed

    Wen, H

    1999-07-01

    Hall effect imaging is an ultrasound-based method of mapping spatial variations in the dielectric constants of an acoustically-uniform sample. This paper presents three-dimensional Hall effect images of phantoms obtained by scanning a single transducer across a two-dimensional grid, effectively simulating two-dimensional phased-array signal reception. The experiments demonstrate the feasibility of volumetric Hall effect tomography and show the advantage of volumetric scans over planar scans. The images reflect several limitations of the current scanning method and point to directions for further hardware development. The inherent limitations of Hall effect imaging are also discussed in light of these results.

  4. Hall and Nernst effects in monolayer MoS2

    NASA Astrophysics Data System (ADS)

    Zhang, Yun-Hai; Zhang, Ming-Hua

    2016-03-01

    We study Hall and Nernst transports in monolayer MoS2 based on Green’s function formalism. We have derived analytical results for spin and valley Hall conductivities in the zero temperature and spin and valley Nernst conductivities in the low temperature. We found that tuning of the band gap and spin-orbit splitting can drive system transition from spin Hall insulator (SHI) to valley Hall insulator (VHI). When the system is subjected to a temperature gradient, the spin and valley Nernst conductivities are dependent on Berry curvature.

  5. Dynamic Feedback in Ferromagnet-Spin Hall Metal Heterostructures

    NASA Astrophysics Data System (ADS)

    Cheng, Ran; Zhu, Jian-Gang; Xiao, Di

    2016-08-01

    In ferromagnet-normal-metal heterostructures, spin pumping and spin-transfer torques are two reciprocal processes that occur concomitantly. Their interplay introduces a dynamic feedback effect interconnecting energy dissipation channels of both magnetization and current. By solving the spin diffusion process in the presence of the spin Hall effect in the normal metal, we show that the dynamic feedback gives rise to (i) a nonlinear magnetic damping that is crucial to sustain uniform steady-state oscillations of a spin Hall oscillator at large angles and (ii) a frequency-dependent spin Hall magnetoimpedance that reduces to the spin Hall magnetoresistance in the dc limit.

  6. Volumetric Hall Effect Tomography – A Feasibility Study

    PubMed Central

    Wen, Han

    2010-01-01

    Hall effect imaging is an ultrasound-based method of mapping spatial variations in the dielectric constants of an acoustically-uniform sample. This paper presents three-dimensional Hall effect images of phantoms obtained by scanning a single transducer across a two-dimensional grid, effectively simulating two-dimensional phased-array signal reception. The experiments demonstrate the feasibility of volumetric Hall effect tomography and show the advantage of volumetric scans over planar scans. The images reflect several limitations of the current scanning method and point to directions for further hardware development. The inherent limitations of Hall effect imaging are also discussed in light of these results. PMID:10604800

  7. Charge carrier coherence and Hall effect in organic semiconductors

    DOE PAGES

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force actingmore » on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Lastly, our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.« less

  8. Probing magnetic microstructures with quasi-ballistic Hall crosses

    NASA Astrophysics Data System (ADS)

    Fasbender, S.; Schluck, J.; Cerchez, M.; Heinzel, T.; Sievers, S.; Pierz, K.; Schumacher, H. W.

    2016-03-01

    Hall sensing is performed on a localized magnetic field pattern using a quasi-ballistic Hall cross device. The Hall resistance shows a pronounced peak as a function of the magnetic field amplitude which is absent in the magnetization hysteresis loop. This non-monotonic response exemplifies qualitatively the failure of conventional Hall sensing. It is demonstrated how, by using a numerical simulation based on the Landauer-Büttiker model, the amplitude of the magnetic field profile can be determined from such measurements.

  9. Topological Hall Effect in Skyrmions: A Nonequilibrium Coherent Transport Approach

    NASA Astrophysics Data System (ADS)

    Yin, Gen; Zang, Jiadong; Lake, Roger

    2014-03-01

    Skyrmion is a topological spin texture recently observed in many materials with broken inversion symmetry. In experiments, one effective method to detect the skyrmion crystal phase is the topological Hall measurement. At adiabatic approximation, previous theoretical studies show that the Hall signal is provided by an emergent magnetic field, which explains the topological Hall effect in the classical level. Motivated by the potential device application of skyrmions as digital bits, it is important to understand the topological Hall effect in the mesoscopic level, where the electron coherence should be considered. In this talk, we will discuss the quantum aspects of the topological Hall effect on a tight binding setup solved by nonequilibrium Green's function (NEGF). The charge distribution, Hall potential distribution, thermal broadening effect and the Hall resistivity are investigated in detail. The relation between the Hall resistance and the DM interaction is investigated. Driven by the spin transferred torque (SST), Skyrmion dynamics is previously studied within the adiabatic approximation. At the quantum transport level, this talk will also discuss the non-adiabatic effect in the skyrmion motion with the presence of the topological Hall effect. This material is based upon work supported by the National Science Foundation under Grant Nos. NSF 1128304 and NSF 1124733. It was also supported in part by FAME, one of six centers of STARnet, an SRC program sponsored by MARCO and DARPA.

  10. 76 FR 64083 - Reliability Technical Conference; Notice of Technical Conference

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Reliability Technical Conference; Notice of Technical Conference Take notice that the Federal Energy Regulatory Commission will hold a Technical Conference on Tuesday, November...

  11. 2011 Asia Pacific Few-Body Conference Summary Remarks

    NASA Astrophysics Data System (ADS)

    Gibson, B. F.

    2013-03-01

    These remarks represent the author's personal perspective regarding ideas presented at this fifth Asia Pacific Conference on Few-Body Problems in Physics. They are not intended as a comprehensive summary of what we witnessed during this week of stimulating presentations and intense discussions. However, these remarks do characterize some of the physics we heard and some of the key questions raised. The ideas presented will hopefully outlive the rapporteurs who brought their work and that of others to our attention here in the International Hall of the Sungkyunkwan University in Seoul, Republic of Korea. Finally, we bid adieu to our friend, colleague, and mentor, John A. Tjon.

  12. Non-invasive Hall current distribution measurement in a Hall effect thruster

    NASA Astrophysics Data System (ADS)

    Mullins, Carl R.; Farnell, Casey C.; Farnell, Cody C.; Martinez, Rafael A.; Liu, David; Branam, Richard D.; Williams, John D.

    2017-01-01

    A means is presented to determine the Hall current density distribution in a closed drift thruster by remotely measuring the magnetic field and solving the inverse problem for the current density. The magnetic field was measured by employing an array of eight tunneling magnetoresistive (TMR) sensors capable of milligauss sensitivity when placed in a high background field. The array was positioned just outside the thruster channel on a 1.5 kW Hall thruster equipped with a center-mounted hollow cathode. In the sensor array location, the static magnetic field is approximately 30 G, which is within the linear operating range of the TMR sensors. Furthermore, the induced field at this distance is approximately tens of milligauss, which is within the sensitivity range of the TMR sensors. Because of the nature of the inverse problem, the induced-field measurements do not provide the Hall current density by a simple inversion; however, a Tikhonov regularization of the induced field does provide the current density distributions. These distributions are shown as a function of time in contour plots. The measured ratios between the average Hall current and the average discharge current ranged from 6.1 to 7.3 over a range of operating conditions from 1.3 kW to 2.2 kW. The temporal inverse solution at 1.5 kW exhibited a breathing mode frequency of 24 kHz, which was in agreement with temporal measurements of the discharge current.

  13. Non-invasive Hall current distribution measurement in a Hall effect thruster.

    PubMed

    Mullins, Carl R; Farnell, Casey C; Farnell, Cody C; Martinez, Rafael A; Liu, David; Branam, Richard D; Williams, John D

    2017-01-01

    A means is presented to determine the Hall current density distribution in a closed drift thruster by remotely measuring the magnetic field and solving the inverse problem for the current density. The magnetic field was measured by employing an array of eight tunneling magnetoresistive (TMR) sensors capable of milligauss sensitivity when placed in a high background field. The array was positioned just outside the thruster channel on a 1.5 kW Hall thruster equipped with a center-mounted hollow cathode. In the sensor array location, the static magnetic field is approximately 30 G, which is within the linear operating range of the TMR sensors. Furthermore, the induced field at this distance is approximately tens of milligauss, which is within the sensitivity range of the TMR sensors. Because of the nature of the inverse problem, the induced-field measurements do not provide the Hall current density by a simple inversion; however, a Tikhonov regularization of the induced field does provide the current density distributions. These distributions are shown as a function of time in contour plots. The measured ratios between the average Hall current and the average discharge current ranged from 6.1 to 7.3 over a range of operating conditions from 1.3 kW to 2.2 kW. The temporal inverse solution at 1.5 kW exhibited a breathing mode frequency of 24 kHz, which was in agreement with temporal measurements of the discharge current.

  14. Hall effect in two-dimensional composites

    NASA Astrophysics Data System (ADS)

    Christiansson, H.

    1997-07-01

    Conduction in a two-component composite film, subject to a magnetic field, is treated numerically with an interface integral equation method. The composite is chosen to be a square array of starfish-shaped inclusions in an anisotropic matrix. Highly accurate calculations are performed and used to investigate microstructure-independent relations between the effective conductivity tensor elements. Asymptotic studies of closely spaced superconducting and insulating disks in an anisotropic matrix verify theoretical results. All the results in this paper are valid for the analog to the Hall effect in heat conduction, the Righi-Leduc effect.

  15. Dissipation and tunneling in quantum Hall bilayers.

    PubMed

    Jack, Robert L; Lee, Derek K K; Cooper, Nigel R

    2004-09-17

    We discuss the interplay between transport and intrinsic dissipation in quantum Hall bilayers, within the framework of a simple thought experiment. We compute, for the first time, quantum corrections to the semiclassical dynamics of this system. This allows us to reinterpret tunneling measurements on these systems. We find a strong peak in the zero-temperature tunneling current that arises from the decay of Josephson-like oscillations into incoherent charge fluctuations. In the presence of an in-plane field, resonances in the tunneling current develop an asymmetric line shape.

  16. Supercurrent in the quantum Hall regime.

    PubMed

    Amet, F; Ke, C T; Borzenets, I V; Wang, J; Watanabe, K; Taniguchi, T; Deacon, R S; Yamamoto, M; Bomze, Y; Tarucha, S; Finkelstein, G

    2016-05-20

    A promising route for creating topological states and excitations is to combine superconductivity and the quantum Hall (QH) effect. Despite this potential, signatures of superconductivity in the QH regime remain scarce, and a superconducting current through a QH weak link has been challenging to observe. We demonstrate the existence of a distinct supercurrent mechanism in encapsulated graphene samples contacted by superconducting electrodes, in magnetic fields as high as 2 tesla. The observation of a supercurrent in the QH regime marks an important step in the quest for exotic topological excitations, such as Majorana fermions and parafermions, which may find applications in fault-tolerant quantum computing.

  17. Chiral partition functions of quantum Hall droplets

    SciTech Connect

    Cappelli, Andrea Viola, Giovanni; Zemba, Guillermo R.

    2010-02-15

    Chiral partition functions of conformal field theory describe the edge excitations of isolated Hall droplets. They are characterized by an index specifying the quasiparticle sector and transform among themselves by a finite-dimensional representation of the modular group. The partition functions are derived and used to describe electron transitions leading to Coulomb blockade conductance peaks. We find the peak patterns for Abelian hierarchical states and non-Abelian Read-Rezayi states, and compare them. Experimental observation of these features can check the qualitative properties of the conformal field theory description, such as the decomposition of the Hilbert space into sectors, involving charged and neutral parts, and the fusion rules.

  18. Segmented electrode hall thruster with reduced plume

    DOEpatents

    Fisch, Nathaniel J.; Raitses, Yevgeny

    2004-08-17

    An apparatus and method for thrusting plasma, utilizing a Hall thruster with segmented electrodes along the channel, which make the acceleration region as localized as possible. Also disclosed are methods of arranging the electrodes so as to minimize erosion and arcing. Also disclosed are methods of arranging the electrodes so as to produce a substantial reduction in plume divergence. The use of electrodes made of emissive material will reduce the radial potential drop within the channel, further decreasing the plume divergence. Also disclosed is a method of arranging and powering these electrodes so as to provide variable mode operation.

  19. Quantum-Hall Activation Gaps in Graphene

    NASA Astrophysics Data System (ADS)

    Giesbers, A. J. M.; Zeitler, U.; Katsnelson, M. I.; Ponomarenko, L. A.; Mohiuddin, T. M.; Maan, J. C.

    2007-11-01

    We have measured the quantum-Hall activation gaps in graphene at filling factors ν=2 and ν=6 for magnetic fields up to 32 T and temperatures from 4 to 300 K. The ν=6 gap can be described by thermal excitation to broadened Landau levels with a width of 400 K. In contrast, the gap measured at ν=2 is strongly temperature and field dependent and approaches the expected value for sharp Landau levels for fields B>20T and temperatures T>100K. We explain this surprising behavior by a narrowing of the lowest Landau level.

  20. Anomalous hydrodynamics of fractional quantum Hall states

    SciTech Connect

    Wiegmann, P.

    2013-09-15

    We propose a comprehensive framework for quantum hydrodynamics of the fractional quantum Hall (FQH) states. We suggest that the electronic fluid in the FQH regime can be phenomenologically described by the quantized hydrodynamics of vortices in an incompressible rotating liquid. We demonstrate that such hydrodynamics captures all major features of FQH states, including the subtle effect of the Lorentz shear stress. We present a consistent quantization of the hydrodynamics of an incompressible fluid, providing a powerful framework to study the FQH effect and superfluids. We obtain the quantum hydrodynamics of the vortex flow by quantizing the Kirchhoff equations for vortex dynamics.

  1. Excitons in the Fractional Quantum Hall Effect

    DOE R&D Accomplishments Database

    Laughlin, R. B.

    1984-09-01

    Quasiparticles of charge 1/m in the Fractional Quantum Hall Effect form excitons, which are collective excitations physically similar to the transverse magnetoplasma oscillations of a Wigner crystal. A variational exciton wavefunction which shows explicitly that the magnetic length is effectively longer for quasiparticles than for electrons is proposed. This wavefunction is used to estimate the dispersion relation of these excitons and the matrix elements to generate them optically out of the ground state. These quantities are then used to describe a type of nonlinear conductivity which may occur in these systems when they are relatively clean.

  2. Town Hall MEETING—SCCM 2009

    NASA Astrophysics Data System (ADS)

    Eggert, J.; Ryan, S. J.; Ramesh, K. T.; Funk, D.; Proud, W. G.

    2009-12-01

    The following article contains the summary of the discussion held at the Shock Compression of Condensed Matter Town Hall Meeting. This was held on Tuesday afternoon of the meeting and attracted 100+ attendees. This meeting, chaired by John Eggert, was planned to introduce challenges in selected topics relevant to shock wave science. The three subjects and speakers were: space research introduced by Shannon Ryan, nanotechnology presented by Kaliat T. Ramesh, and compression tools delivered by Dave Funk. After each presentation there were a number of questions.

  3. Duality in the quantum Hall system

    NASA Astrophysics Data System (ADS)

    Lütken, C. A.; Ross, G. G.

    1992-05-01

    We suggest that a unified description of the integer and fractional phases of the quantum Hall system may be possible if the scaling diagram of transport coefficients is invariant under linear fractional (modular) transformations. In this model the hierarchy of states, as well as the observed universality of critical exponents, are consequences of a discrete SL(2,openZ) symmetry acting on the parameter space of an effective quantum-field theory. Available scaling data on the position of delocalization fixed points in the integer case and the position of mobility fixed points in the fractional case agree with the model within experimental accuracy.

  4. Hypernuclear spectroscopy program at JLab Hall C

    SciTech Connect

    Hashimoto, Osamu; Hashimoto, Osamu; Nakamura, Satoshi; Acha Quimper, Armando; Ahmidouch, Abdellah; Androic, Darko; Asaturyan, Arshak; Asaturyan, Razmik; Baker, O.; Baturin, Pavlo; Benmokhtar, Fatiha; Bosted, Peter; Carlini, Roger; Chen, X.; Christy, Michael; Cole, Leon; Danagoulian, Samuel; Daniel, AJI; Dharmawardane, Kahanawita; Egiyan, Kim; Elaasar, Mostafa; Ent, Rolf; Fenker, Howard; Fujii, Yu; Furic, Miroslav; Gan, Liping; Gaskell, David; Gasparian, Ashot; Gibson, Edward; Gueye, Paul; Halkyard, Rebekah; Honda, D.; Horn, Tanja; Hu, Bitao; Hu, S.; Hungerford, Ed; Ispiryan, Mikayel; Johnston, Kathleen; Jones, Mark; Kalantarians, Narbe; Kaneta, M.; Kato, F.; Kato, Seigo; Kawama, Daisuke; Keppel, Cynthia; Li, Ya; Luo, Wei; Mack, David; Margaryan, Amur; Marikyan, Gagik; Maruyama, Nayuta; Matsumura, Akihiko; Miyoshi, Toshinobu; Mkrtchyan, Arthur; Mkrtchyan, Hamlet; Navasardyan, Tigran; Niculescu, Gabriel; Niculescu, Maria-Ioana; Nomura, Hiroshi; Nonaka, Kenichi; Ohtani, Atsushi; Okayasu, Yuichi; Pamela, Priscilla; Perez, Naipy; Petkovic, Tomislav; Randeniya, Kapugodage; Reinhold, Joerg; Rivera Castillo, Roberto; Roche, Julie; Rodriguez, Victor; Sato, Yoshinori; Seva, Tomislav; Tang, Liguang; Simicevic, Neven; Smith, Gregory; Sumihama, Mizuki; Song, Y.; Tadevosyan, Vardan; Takahashi, Toshiyuki; Tamura, Hirokazu; Tvaskis, Vladas; Vulcan, William; Wang, B.; Wells, Steven; Yan, Chen; Yuan, Lulin; Zamkochian, S.

    2008-05-01

    DOI: http://dx.doi.org/10.1016/j.nuclphysa.2008.01.029
    Hypernuclear production by the (e,e?K+) reaction has unique advantages in hypernuclear spectroscopy of the S=?1 regime. The second-generation spectroscopy experiment on 12C, 7Li and 28Si targets has been recently carried out at JLab Hall C with a new experimental configuration (Tilt method) and also using a new high-resolution kaon spectrometer (HKS). The experiment is described and preliminary results are presented together with the empasis of significance of the (e,e?K+) reaction for ? hypernuclear spectroscopy and its future prospects.

  5. Anesthetic considerations in Sheldon-Hall syndrome.

    PubMed

    Anderson, Thomas Anthony; Kasser, James R; Holzman, Robert S

    2014-05-01

    Arthrogryposis is characterized by multiple, nonprogressive joint contractures which may be caused by maternal disorders such as oligohydramnios as well as fetal akinesia resulting from primary disorders of muscle, connective tissue, or neurologic tissue. Its prevalence is about 1 : 3000. Distal arthrogryposis (DA) is a heterogenous group of genetic disorders with a characteristic flexion of the joints of the hands and feet divided into different types with additional features. Sheldon-Hall Syndrome (SHS), also known as distal arthrogryposis type 2A (DA2A), has some nonorthopedic features of specific importance to anesthetic care.

  6. Supercurrent in the quantum Hall regime

    NASA Astrophysics Data System (ADS)

    Amet, F.; Ke, C. T.; Borzenets, I. V.; Wang, J.; Watanabe, K.; Taniguchi, T.; Deacon, R. S.; Yamamoto, M.; Bomze, Y.; Tarucha, S.; Finkelstein, G.

    2016-05-01

    A promising route for creating topological states and excitations is to combine superconductivity and the quantum Hall (QH) effect. Despite this potential, signatures of superconductivity in the QH regime remain scarce, and a superconducting current through a QH weak link has been challenging to observe. We demonstrate the existence of a distinct supercurrent mechanism in encapsulated graphene samples contacted by superconducting electrodes, in magnetic fields as high as 2 tesla. The observation of a supercurrent in the QH regime marks an important step in the quest for exotic topological excitations, such as Majorana fermions and parafermions, which may find applications in fault-tolerant quantum computing.

  7. Effect of Joule heating on current-induced asymmetries and breakdown of the quantum Hall effect in narrow Hall bars

    NASA Astrophysics Data System (ADS)

    Gerhardts, Rolf R.

    2017-01-01

    Recent low-temperature scanning-force-microscopy experiments on narrow Hall bars, under the conditions of the integer quantum Hall effect (IQHE) and its breakdown, have revealed an interesting position dependence of the Hall potential, which changes drastically with the applied magnetic field and the strength of the imposed current through the sample. The present paper shows, that inclusion of Joule heating into an existing self-consistent theory of screening and magneto-transport, which assumes translation invariant Hall bars with a homogeneous background charge due to doping, can explain the experimental results on the breakdown of the IQHE in the so called edge-dominated regime.

  8. Synchronization of spin-transfer torque oscillators by spin pumping, inverse spin Hall, and spin Hall effects

    SciTech Connect

    Elyasi, Mehrdad; Bhatia, Charanjit S.; Yang, Hyunsoo

    2015-02-14

    We have proposed a method to synchronize multiple spin-transfer torque oscillators based on spin pumping, inverse spin Hall, and spin Hall effects. The proposed oscillator system consists of a series of nano-magnets in junction with a normal metal with high spin-orbit coupling, and an accumulative feedback loop. We conduct simulations to demonstrate the effect of modulated charge currents in the normal metal due to spin pumping from each nano-magnet. We show that the interplay between the spin Hall effect and inverse spin Hall effect results in synchronization of the nano-magnets.

  9. The Learning Conference

    ERIC Educational Resources Information Center

    Ravn, Ib

    2007-01-01

    Purpose: The purpose of this paper is to call attention to the fact that conferences for professionals rely on massive one-way communication and hence produce little learning for delegates--and to introduce an alternative, the "learning conference", that involves delegates in fun and productive learning processes.…

  10. ASE Annual Conference 2010

    ERIC Educational Resources Information Center

    McCune, Roger

    2010-01-01

    In this article, the author describes the ASE Annual Conference 2010 which was held at Nottingham after a gap of 22 years. As always, the main conference was preceded by International Day, an important event for science educators from across the world. There were two strands to the programme: (1) "What works for me?"--sharing new ideas…

  11. Lyndon Johnson's Press Conferences.

    ERIC Educational Resources Information Center

    Cooper, Stephen

    Because President Lyndon Johnson understood well the publicity value of the American news media, he sought to exploit them. He saw reporters as "torch bearers" for his programs and policies and used the presidential press conference chiefly for promotional purposes. Although he met with reporters often, his press conferences were usually…

  12. From Conference to Journal

    ERIC Educational Resources Information Center

    McCartney, Robert; Tenenberg, Josh

    2008-01-01

    Revising and extending conference articles for journal publication benefits both authors and readers. The new articles are more complete, and benefit from peer review, feedback from conference presentation, and greater editorial consistency. For those articles that are appropriate, we encourage authors to do this, and present two examples of such…

  13. ICCK Conference Final Report

    SciTech Connect

    Green, William H.

    2013-05-28

    The 7th International Conference on Chemical Kinetics (ICCK) was held July 10-14, 2011, at Massachusetts Institute of Technology (MIT), in Cambridge, MA, hosted by Prof. William H. Green of MIT's Chemical Engineering department. This cross-disciplinary meeting highlighted the importance of fundamental understanding of elementary reactions to the full range of chemical investigations. The specific conference focus was on elementary-step kinetics in both the gas phase and in condensed phase. The meeting provided a unique opportunity to discuss how the same reactive species and reaction motifs manifest under very different reaction conditions (e.g. atmospheric, aqueous, combustion, plasma, in nonaqueous solvents, on surfaces.). The conference featured special sessions on new/improved experimental techniques, improved models and data analysis for interpreting complicated kinetics, computational kinetics (especially rate estimates for large kinetic models), and a panel discussion on how the community should document/archive kinetic data. In the past, this conference had been limited to homogeneous gas-phase and liquid-phase systems. This conference included studies of heterogeneous kinetics which provide rate constants for, or insight into, elementary reaction steps. This Grant from DOE BES covered about half of the subsidies we provided to students and postdocs who attended the conference, by charging them reduced-rate registration fees. The complete list of subsidies provided are listed in Table 1 below. This DOE funding was essential to making the conference affordable to graduate students, and indeed the attendance at this conference was higher than at previous conferences in this series. Donations made by companies provided additional subsidies, leveraging the DOE funding. The conference was very effective in educating graduate students and important in fostering scientific interactions, particularly between scientists studying gas phase and liquid phase kinetics

  14. PREFACE: 7th International Conference on Cooling & Heating Technologies (ICCHT 2014)

    NASA Astrophysics Data System (ADS)

    2015-09-01

    The Kyoto protocol has initiated a pledge from almost all developing and developed countries to be committed to reducing CO2 emissions. Development of new renewable energy technologies are also of interest in this conference. Greenhouse gases have contributed to global warming and other man-made disasters. Cooling and Heating communities also have responsibilities towards the commitment of reducing the greenhouse gas emissions. In addition, depleting natural resources also act as a threat to the Cooling and Heating industries, causing them to develop highly efficient equipment and innovative technologies. The 1st International Conference on Cooling & Heating Technologies was held in Hanoi Vietnam (Jan. 2005). Whereas the 2nd, 3rd, 4th and 5th ICCHT conferences were held in Dalian, China (Jul. 2006), Tokyo, Japan (Jul. 2007), Jinhae, Korea (Oct. 2008) and Bandung, Indonesia (Dec. 2010) respectively. The 6th International Conference on Cooling & Heating Technologies (ICCTH2012) was held in Xi'an in China on November 9-12, 2012. It is our pleasure to welcome you to the 7th International Conference on Cooling & Heating Technologies (ICCTH2014) on 4th - 6th November 2014 at the Grand Dorsett Subang Hotel, Subang Jaya, Selangor Darul Ehsan, Malaysia The Theme of the Conference is ''Sustainability and Innovation in Heating & Cooling Technologies''. The sub-themes are:- • CO2 Reduction and Low Carbon Technologies • HVAC System and Natural Ventilation • Energy & Alternative Energy • Computational Fluid Dynamics • Low Temperature & Refrigeration Engineering In conjunction with the Conference, an Exhibition will be organized as an integral part of the Conference. Project experiences, product solutions, new applications and state-of-the art information will be highlighted.

  15. Repurposing the Caltech Robinson Hall Coelostat

    NASA Astrophysics Data System (ADS)

    Treffers, Richard R.; Loisos, G.; Ubbelohde, M.; Douglas, S.; Martinez, M.

    2013-01-01

    We describe the repurposing of the historic coelostat atop Caltech’s Robinson Hall for building lighting, public education and scientific research. The coelostat was originally part of George Ellery Hale’s vision of the Astrophysical Laboratory on the Caltech campus in 1932. The coelostat, designed by Russell Porter, has a 36 inch diameter primary mirror a 30 inch diameter secondary mirror and provides a 24 inch un-vignetted beam of sunlight into the building. Although constructed in the 1930s, due to wartime pressures and other projects, it was used only briefly in the 1970s and never fully realized. Recently Robinson Hall has been fully renovated to house the Ronald and Maxine Linde Center for Global Environmental Science. The coelostat operation was modernized replacing the old motors and automating all the motions. Each morning, if the weather cooperates, the dome slit opens, the mirrors configured and sunlight pours into the building. The beam of sunlight is divided into three parts. One part goes into a refracting telescope which projects a ten inch diameter of the sun onto a ground glass screen visible to the public. A second fraction is distributed to fiber optic fixtures that illuminate some of the basement rooms. The final fraction goes into two laboratories where it is used in experiments monitoring trace constituents of our atmosphere and for solar catalysis experiments. The instrument as originally conceived required at least two human operators. Now it is fully automatic and doing real science

  16. Universality in the Fractional Quantum Hall effect

    NASA Astrophysics Data System (ADS)

    Fradkin, Eduardo; Lopez, Ana

    1993-11-01

    In this lectures we review the fermion field theoretic approach to the Fractional Quantum Hall Effect and use it to discuss the origin of its remarkable universality. We discuss the semiclassical expansion around the average field approximation (AFA). We reexamine the AFA and the role of fluctuations. We argue that, order-by-order in the semiclassical expansion, the response functions obey the correct symmetry properties required by Galilean and Gauge Invariance and by the incompressibility of the fluid. In particular, we find that the low-momentum limit of the semiclassical approximation to the response functions is exact and that it saturates the f-sum rule. We discuss the nature of the spectrum of collective excitations of FQHE systems in the low-momentum limit. We applied these results to the problem of the screening of external charges and fluxes by the electron fluid, and obtained asymptotic expressions of the charge and current density profiles, for different types of interactions. The universality of the FQHE is demonstrated by deriving the form of the wave function of the ground state at long distances. We show that the wave functions of the fluid ground states of Fractional Quantum Hall systems, in the thermodynamic limit, are universal at long distances and that they have a generalized Laughlin form. This universality is a consequence of the analytic properties of the equal-time density correlation functions at long distances.

  17. Universality in the Fractional Quantum Hall

    NASA Astrophysics Data System (ADS)

    Fradkin, Eduardo; Lopez, Ana

    In this set of lectures we review the fermion field theoretic approach to the Fractional Quantum Hall Effect and use it to discuss the origin of its remarkable universality. We discuss the semiclassical expansion around the average field approximation (AFA). We reexamine the AFA and the role of fluctuations. We argue that, order-by-order in the semiclassical expansion, the response functions obey the correct symmetry properties required by Galilean and Gauge Invariance and by the incompressibility of the fluid. In particular, we find that the low-momentum limit of the semiclassical approximation to the response functions is exact and that it saturates the f-sum rule. We discuss the nature of the spectrum of collective excitations of FQHE systems in the low-momentum limit. We applied these results to the problem of the screening of external charges and fluxes by the electron fluid, and obtained asymptotic expressions of the charge and current density profiles, for different types of interactions. The universality of the FQHE is demonstrated by deriving the form of the wave function of the ground state at long distances. We show that the wave functions of the fluid ground states of Fractional Quantum Hall systems, in the thermodynamic limit, are universal at long distances and that they have a generalized Laughlin form. This universality is a consequence of the analytic properties of the equaltime density correlation functions at long distances.

  18. Resonant tunneling in fractional Hall effect

    NASA Astrophysics Data System (ADS)

    Shi, Chuntai; Jain, Jainendra

    2006-03-01

    We study theoretically the possible transitions of a fractional quantum Hall island surrounded by another fractional quantum Hall state, induced by either the variation of the magnetic field or a backgate voltage, and find a rich set of possibilities in addition to the one considered previously[1],The elementary transitions correspond to the addition or removal of a composite fermion from the edge or the interior of the island; combinations of elementary transitions may occur simultaneously due to electrostatic constraints. Relevance to a recent experiment[2] is considered, which measures the resonant tunneling of composite fermions through their quasi-bound states around such a 2/5 island surrounded by the 1/3 sea. It is shown that the results are consistent with the notion of fractional braiding statistics, but can be explained on the basis of fractional charge alone. We also perform calculations based on microscopic composite fermion wavefunctions of finite systems to test the theoretical considerations. [1]J.K.Jain, S.A.Kivelson, and D.J.Thouless, Phys.Rev.Lett.71, 3003(1993). [2]F.E.Camino, W.Zhou, and V.J.Goldman, Phys.Rev.B 72, 075342(2005).

  19. Hall Effect Measured Using a Waveguide Tee

    NASA Astrophysics Data System (ADS)

    Coppock, Joyce; Anderson, James; Johnson, William

    2014-03-01

    We describe a simple microwave apparatus to measure the Hall effect in semiconductor wafers. The advantage of this technique is that it does not require contacts on the sample or the use of a resonant cavity. Our method consists of placing the semiconductor wafer into a slot cut in an X-band waveguide tee, which lies in the center of an electromagnet, injecting power into the two opposing arms of the tee, and measuring the output at the third arm. Application of a magnetic field gives a Hall signal that is linear in the magnetic field and which reverses phase when the magnetic field is reversed. This method yields the semiconductor mobility, which we can compare for calibration purposes with mobility data from direct-current (Van der Pauw1) measurements. We are in the process of modeling the system using a finite-difference time-domain (FDTD) simulation to better understand the behavior of the electric fields inside the sample. Resistivity data is obtained by measuring the microwave reflection coefficient of the sample. This talk presents data for silicon and germanium samples doped with boron or phosphorus. Measured mobilities ranged from 270-3000 cm2/V.s . 1L. J. van der Pauw, PhilipsResearchReports 13, 1 (1958)

  20. Cylindrical Hall Thrusters with Permanent Magnets

    SciTech Connect

    Raitses, Yevgeny; Merino, Enrique; Fisch, Nathaniel J.

    2010-10-18

    The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction of both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50W-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT. __________________________________________________

  1. Cylindrical Hall thrusters with permanent magnets

    NASA Astrophysics Data System (ADS)

    Raitses, Yevgeny; Merino, Enrique; Fisch, Nathaniel J.

    2010-11-01

    The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction in both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT.

  2. Intrinsic valley Hall effect in graphene

    NASA Astrophysics Data System (ADS)

    Yang, Mou; Zhang, Wen-Lian; Liu, Hai; Bai, Yan-Kui

    2017-04-01

    If electrons are incident from an armchair graphene ribbon into the bulk graphene region, the electronic diffraction occurs. Because of the different triangular wrapping of the energy dispersion between valleys K and K ‧ , the electrons of valley K tend to be diffracted to one side and those of valley K ‧ to the other side. When the current is injected from the armchair ribbon of a four-terminal graphene device, the major portion of the incident current of valley K flows through one side arm and the minor portion through the other side arm. The ratio between them is derived to be 1 + 4 E / 3 in the low energy limit, where E is the energy in units of hopping parameter. The major arm for valley K is the minor arm for valley K ‧ . This results in the rise of the valley Hall effect, which is an intrinsic property of graphene stemming from the different electronic structure of the two valleys. The valley Hall conductance is calculated to be (2 E / 3)G0 with G0 being the conductance supported by the injection ribbon.

  3. New melting transition in Quantum Hall systems

    NASA Astrophysics Data System (ADS)

    Simion, George; Lin, Tsuging; Watson, John D.; Manfra, Michael J.; Csathy, Gabor; Rokhinson, Leonid; Lyanda-Geller, Yuli

    2014-03-01

    We discover a new melting transition caused by topological excitations of two dimensional electrons in the quantum Hall regime. Experimentally, strain dependence of resistivity changes sign upon crossing filling-factor-specified boundaries of reentrant integer quantum Hall effect (RIQHE) states. This observation violates the symmetry of electron bubble crystal, whose melting was thought to be responsible for insulator to metal transition in the range of RIQHE filling factors. We demonstrate theoretically that electron bubbles become elongated in the vicinity of charge defects and form textures of finite size. Textures lower the energy of excitations. In the two-electron bubble crystal these textures form hedgehogs (vortices) around defects having (lacking) one extra electron. At low density these textures form an insulating Abrikosov lattice. At densities sufficient to cause the textures to overlap, their interactions are described by the XY-model and the defect lattice melts. This explains the sharp metal-insulator transition observed in finite temperature conductivity measurements. In this regime, melting is a function of several variables and forms a continuous phase boundary in the field-temperature (B - T) plane. Research was partially supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Awards DE-SC0010544 (Y.L-G), DE-SC0008630 (L.P.R.), DE-SC0006671 (G.S. and M.M.).

  4. New topological excitations in quantum Hall systems

    NASA Astrophysics Data System (ADS)

    Lyanda-Geller, Yuli; Lin, Tsuging; Simion, George; Watson, John D.; Manfra, Michael J.; Csathy, Gabor; Rokhinson, Leonid

    2014-03-01

    We discover new topological excitations of two dimensional electrons in the quantum Hall regime. The strain dependence of resistivity observed experimentally is shown to change sign upon crossing filling-factor-specified boundaries of reentrant integer quantum Hall effect (RIQHE) states. This observation violates the known symmetry of electron bubbles thought to be responsible for the RIQHE. We demonstrate theoretically that electron bubbles become elongated in the vicinity of charge defects and form textures of finite size. Calculations confirm that textures lower the energy of excitations. In the two-electron bubble crystal these textures form two-dimensional hedgehogs around defects having one extra electron, and vortices around defects lacking one electron. Strain affects vortices and hedgehogs differently, explaining striking strain-dependent resistivity. The sharp transition from insulating RIQHE state to conducting state is caused by melting of Abrikosov crystal comprised of the defects. The proposed physical mechanism of conductivity due to topological defects is shown to lead to an unusually large magnitude of the strain effect on resistivity in the range of RIQHE filling factors, in agreement with experiment. Research was partially supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Awards DE-SC0010544 (Y.L-G), DE-SC0008630 (L.P.R.), DE-SC0006671 (G.S. and M.M.).

  5. A Preliminary Investigation of Hall Thruster Technology

    NASA Technical Reports Server (NTRS)

    Gallimore, Alec D.

    1997-01-01

    A three-year NASA/BMDO-sponsored experimental program to conduct performance and plume plasma property measurements on two Russian Stationary Plasma Thrusters (SPTs) has been completed. The program utilized experimental facilitates at the University of Michigan's Plasmadynamics and Electric Propulsion Laboratory (PEPL). The main features of the proposed effort were as follows: (1) Characterized Hall thruster (and arcjet) performance by measuring ion exhaust velocity with probes at various thruster conditions; (2) Used a variety of probe diagnostics in the thruster plume to measure plasma properties and flow properties including T(sub e) and n(sub e) ion current density and ion energy distribution, and electric fields by mapping plasma potential; (3) Used emission spectroscopy to identify species within the plume and to measure electron temperatures. A key and unique feature of our research was our collaboration with Russian Hall thruster researcher Dr. Sergey A Khartov, Deputy Dean of International Relations at the Moscow Aviation Institute (MAI). His activities in this program included consulting on and participation in research at PEPL through use of a MAI-built SPT and ion energy probe.

  6. Undulator Hall Air Temperature Fault Scenarios

    SciTech Connect

    Sevilla, J.; Welch, J.; /SLAC

    2010-11-17

    Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about {+-}2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

  7. Quantum Hall Effect and Quillen Metric

    NASA Astrophysics Data System (ADS)

    Klevtsov, Semyon; Ma, Xiaonan; Marinescu, George; Wiegmann, Paul

    2017-02-01

    We study the generating functional, the adiabatic curvature and the adiabatic phase for the integer quantum Hall effect (QHE) on a compact Riemann surface. For the generating functional we derive its asymptotic expansion for the large flux of the magnetic field, i.e., for the large degree k of the positive Hermitian line bundle L k . The expansion consists of the anomalous and exact terms. The anomalous terms are the leading terms of the expansion. This part is responsible for the quantization of the adiabatic transport coefficients in QHE. We then identify the non-local (anomalous) part of the expansion with the Quillen metric on the determinant line bundle, and the subleading exact part with the asymptotics of the regularized spectral determinant of the Laplacian for the line bundle L k , at large k. Finally, we show how the generating functional of the integer QHE is related to the gauge and gravitational (2+1)d Chern-Simons functionals. We observe the relation between the Bismut-Gillet-Soulé curvature formula for the Quillen metric and the adiabatic curvature for the electromagnetic and geometric adiabatic transport of the integer Quantum Hall state. We then obtain the geometric part of the adiabatic phase in QHE, given by the Chern-Simons functional.

  8. Hypernuclear Spectroscopy at JLab Hall C

    SciTech Connect

    Hashimoto, Osamu; Doi, Daisuke; Fujii, Yu; Toshiyuki, Gogami; Kanda, Hiroki; Kaneta, M; Kawama, Daisuke; Maeda, Kazushige; Maruta, Tomofumi; Matsumura, Akihiko; Nagao, Sho; Nakamura, Satoshi; Shichijo, Ayako; Tamura, Hirokazu; Taniya, Naotaka; Yamamoto, Taku; Yokota, Kosuke; Kato, S; Sato, Yoshinori; Takahashi, Toshiyuki; Noumi, Hiroyuki; Motoba, T; Hiyama, E; Albayrak, Ibrahim; Ates, Ozgur; Chen, Chunhua; Christy, Michael; Keppel, Cynthia; Kohl, Karl; Li, Ya; Liyanage, Anusha Habarakada; Tang, Liguang; Walton, T; Ye, Zhihong; Yuan, Lulin; Zhu, Lingyan; Baturin, Pavlo; Boeglin, Werner; Dhamija, Seema; Markowitz, Pete; Raue, Brian; Reinhold, Joerg; Hungerford, Ed; Ent, Rolf; Fenker, Howard; Gaskell, David; Horn, Tanja; Jones, Mark; Smith, Gregory; Vulcan, William; Wood, Stephen; Johnston, C; Simicevic, Neven; Wells, Stephen; Samantha, Chhanda; Hu, Bitao; Shen, Ji; Wang, W; Zhang, Xiaozhuo; Zhang, Yi; Feng, Jing; Fu, Y; Zhou, Jian; Zhou, S; Jiang, Yi; Lu, H; Yan, Xinhu; Ye, Yunxiu; Gan, Liping; Ahmidouch, Abdellah; Danagoulian, Samuel; Gasparian, Ashot; Elaasar, Mostafa; Wesselmann, Frank; Asaturyan, Arshak; Margaryan, Amur; Mkrtchyan, Arthur; Mkrtchyan, Hamlet; Tadevosyan, Vardan; Androic, Darko; Furic, Miroslav; Petkovic, Tomislav; Seva, Tomislav; Niculescu, Gabriel; Niculescu, Maria-Ioana; Rodriguez, Victor; Cisbani, Evaristo; Cusanno, Francesco; Garibaldi, Franco; Urciuoli, Guido; De Leo, Raffaele; Maronne, S; Achenbach, Carsten; Pochodzalla, J

    2010-03-01

    Since the 1st generation experiment, E89-009, which was successfully carried out as a pilot experiment of (e,e'K+) hypernuclear spectroscopy at JLab Hall C in 2000, precision hypernuclear spectroscopy by the (e,e'K+) reactions made considerable progress. It has evolved to the 2nd generation experiment, E01-011, in which a newly constructed high resolution kaon spectrometer (HKS) was installed and the “Tilt method” was adopted in order to suppress large electromagnetic background and to run with high luminosity. Preliminary high-resolution spectra of 7ΛHe and 28ΛAl together with that of 12ΛB that achieved resolution better than 500 keV(FWHM) were obtained. The third generation experiment, E05-115, has completed data taking with an experimental setup combining a new splitter magnet, high resolution electron spectrometer (HES) and the HKS used in the 2nd generation experiment. The data were accumulated with targets of 7Li, 9Be, 10B, 12C and 52Cr as well as with those of CH2 and H2O for calibration. The analysis is under way with particular emphasis of determining precision absolute hypernuclear masses. In this article, hypernuclear spectroscopy program in the wide mass range at JLab Hall C that has undergone three generation is described.

  9. Quantum anomalous Hall state in bilayer graphene

    NASA Astrophysics Data System (ADS)

    Nandkishore, Rahul; Levitov, Leonid

    2010-09-01

    We present a symmetry-based analysis of competition between different gapped states that have been proposed in bilayer graphene (BLG), which are all degenerate on a mean-field level. We classify the states in terms of a hidden SU(4) symmetry, and distinguish symmetry-protected degeneracies from accidental degeneracies. One of the states, which spontaneously breaks discrete time-reversal symmetry but no continuous symmetry, is identified as a quantum anomalous Hall (QAH) state, which exhibits quantum Hall effect at zero magnetic field. We investigate the lifting of the accidental degeneracies by thermal and zero-point fluctuations, taking account of the modes softened under renormalization group (RG). Working in a “saddle point plus quadratic fluctuations” approximation, we identify two types of RG-soft modes which have competing effects. Zero-point fluctuations, dominated by “transverse” modes which are unique to BLG, favor the QAH state. Thermal fluctuations, dominated by “longitudinal” modes, favor a SU(4) symmetry-breaking multiplet of states. We discuss the phenomenology and experimental signatures of the QAH state in BLG, and also propose a way to induce the QAH state using weak external magnetic fields.

  10. Tunneling current through fractional quantum Hall interferometers

    NASA Astrophysics Data System (ADS)

    Smits, O.; Slingerland, J. K.; Simon, S. H.

    2014-01-01

    We calculate the tunneling current through a Fabry-Pérot interferometer in the fractional quantum Hall regime. Within linear response theory (weak tunneling but arbitrary source-drain voltage), we find a general expression for the current due to tunneling of quasiparticles in terms of Carlson's R function. Our result is valid for fractional quantum Hall states with an edge theory consisting of a charged channel and any number of neutral channels, with possibly different edge velocities and different chiralities. We analyze the case with a single neutral channel in detail, which applies for instance to the edge of the Moore-Read state. In addition, we consider an asymmetric interferometer with different edge lengths between the point contacts on opposite edges, and we study the behavior of the current as a function of varying edge length. Recent experiments attempted to measure the Aharanov-Bohm effect by changing the area inside the interferometer using a plunger gate. Theoretical analyses of these experiments have so far not taken into account the accompanying change in the edge lengths. We show that the tunneling current exhibits multiple oscillations as a function of this edge length, with frequencies proportional to the injected edge current and inversely proportional to the edge velocities. In particular, the edge velocities can be measured by looking at the Fourier spectrum of the edge current. We provide a numerical scheme to calculate and plot the R function, and include sample plots for a variety of edge states with parameter values, which are experimentally relevant.

  11. Hall-Effect Thruster Utilizing Bismuth as Propellant

    NASA Technical Reports Server (NTRS)

    Szabo, James; Gasdaska, Charles; Hruby, Vlad; Robin, Mike

    2008-01-01

    A laboratory-model Hall-effect spacecraft thruster was developed that utilizes bismuth as the propellant. Xenon was used in most prior Hall-effect thrusters. Bismuth is an attractive alternative because it has a larger atomic mass, a larger electron-impact-ionization cross-section, and is cheaper and more plentiful.

  12. 34. Photographic copy of first floor plan of Bowditch Hall, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. Photographic copy of first floor plan of Bowditch Hall, Alfred Hopkins & Associates, 1943. Drawing on file at Caretaker Site Office, Naval Undersea Warfare Center, New London. Copyright-free. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT

  13. 35. Photographic copy of second floor plan of Bowditch Hall, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. Photographic copy of second floor plan of Bowditch Hall, Alfred Hopkins & Associates, 1943. Drawing on file at Caretaker Site Office, Naval Undersea Warfare Center, New London. Copyright-free. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT

  14. 36. Photographic copy of third floor plan of Bowditch Hall, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. Photographic copy of third floor plan of Bowditch Hall, Alfred Hopkins & Associates, 1943. Drawing on file at Caretaker Site Office, Naval Undersea Warfare Center, New London. Copyright-free. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT

  15. 30. VIEW OF DRILL HALL FROM SECOND FLOOR EAST BALCONY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. VIEW OF DRILL HALL FROM SECOND FLOOR EAST BALCONY FACING WEST. SHOWS ALTERNATE BAY X BRACING OF ROOF TRUSSES. ALSO SHOWS TRUSSES, WINDOWS IN THE MONITOR, STAIRWAY AT THE SOUTHWEST CORNER OF THE DRILL HALL AND THE THREE LEVELS OF BENCHES ON THE BALCONY. - Yakima National Guard Armory, 202 South Third Street, Yakima, Yakima County, WA

  16. High Life: 17th Annual Residence Hall Construction Report

    ERIC Educational Resources Information Center

    Agron, Joe

    2006-01-01

    Residence hall construction continues to be a priority for colleges and universities. With enrollments on the upswing, higher-education institutions are spending more and building larger facilities to entice students to live on campus. This article presents the findings of "American School & University's" 17th annual Residence Hall Construction…

  17. Pair spectrometer hodoscope for Hall D at Jefferson Lab

    DOE PAGES

    Barbosa, Fernando J.; Hutton, Charles L.; Sitnikov, Alexandre; ...

    2015-09-21

    We present the design of the pair spectrometer hodoscope fabricated at Jefferson Lab and installed in the experimental Hall D. The hodoscope consists of thin scintillator tiles; the light from each tile is collected using wave-length shifting fibers and detected using a Hamamatsu silicon photomultiplier. Light collection was measured using relativistic electrons produced in the tagger area of the experimental Hall B.

  18. Stuart Hall on Racism and the Importance of Diasporic Thinking

    ERIC Educational Resources Information Center

    Rizvi, Fazal

    2015-01-01

    In this article, I want to show how my initial encounter with the work of Stuart Hall was grounded in my reading of the later philosophy of Ludwig Wittgenstein, and was shaped by my interest in understanding the nature of racism across the three countries in which I had lived. Over the years, Hall's various writings have helped me to make sense of…

  19. Useful Pedagogical Applications of the Classical Hall Effect

    ERIC Educational Resources Information Center

    Houari, Ahmed

    2007-01-01

    One of the most known phenomena in physics is the Hall effect. This is mainly due to its simplicity and to the wide range of its theoretical and practical applications. To complete the pedagogical utility of the Hall effect in physics teaching, I will apply it here to determine the Faraday constant as a fundamental physical number and the number…

  20. Whose Big Prize? A Response to Hall and Gunter

    ERIC Educational Resources Information Center

    Furlong, John

    2009-01-01

    This article presents the author's response to Hall and Gunter who accuse the author of trying to mount "a stout defence" of New Labour's reforms of the teaching profession. Hall and Gunter go further and accuse the author of "triumphalism" in his use of the title "Tony Blair's big prize". Their second and more…

  1. Varsity Hall: The Infirmary at the University of Virginia

    ERIC Educational Resources Information Center

    Christmas, William A.; Turner, James C.

    2008-01-01

    In the past 5 years, an important treasure for the field of college health was rediscovered and has been completely renovated. It is the original student infirmary, now called Varsity Hall, at the University of Virginia in Charlottesville. Varsity Hall is a significant rediscovery for those who are interested in the history of college health. This…

  2. The first vineyard concert hall in North America

    NASA Astrophysics Data System (ADS)

    Jaffe, Christopher; Rivera, Carlos

    2002-11-01

    The first vineyard or surround concert hall designed and built in the Western Hemisphere is the Sala Nezahualcoyotl in Mexico City. The Hall was completed in 1976 and is part of the Cultural Center at the Universidad Nacional Autonoma de Mexico. The hall was named after a Toltec poet, architect, and musician who lived in the 15th century and was the Renaissance man of his day. In order to provide the familiar traditional sound of the rectangular (shoebox) European Hall, the acoustic designers set the criteria for reverberation times through the frequency spectrum and the Initial Time Delay Gap at every seat in the house to match the measurements taken at the Grosser Musik vereinssaal in Vienna and Boston Symphony Hall. In this paper we discuss the techniques used to create the traditional sound in a vineyard hall and the reaction of musicians and audiences to the completed facility. The Sala was the model for Suntory Hall in Japan which in turn spawned a number of vineyard halls in Japan. Most recently, the vineyard style seems to be appealing to more and more symphonic organizations in Europe and North America.

  3. A Larger Scale. Tenth Annual Residence Hall Construction Report.

    ERIC Educational Resources Information Center

    Argon, Joe

    1999-01-01

    Presents data from the American School & University's 10th Annual Residence Hall Construction Report that show dormitories are costing more per square foot to build while also becoming larger accommodations. Data tables are provided as are highlighted discussions that include residence hall design flexibility, environmental concerns and building…

  4. Mary E. Hall: Dawn of the Professional School Librarian

    ERIC Educational Resources Information Center

    Alto, Teresa

    2012-01-01

    A century ago, a woman named Mary E. Hall convinced school leaders of the need for the professional school librarian--a librarian who cultivated a love of reading, academic achievement, and independent learning skills. After graduating from New York City's Pratt Institute Library School in 1895, Hall developed her vision for the high school…

  5. 2010 Tetrapyrroles, Chemistry & Biology of Gordon Research Conference

    SciTech Connect

    Angela Wilks

    2010-07-30

    The objective of the Chemistry & Biology of Tetrapyrroles Gordon Conference is to bring together researchers from diverse disciplines that otherwise would not interact. By bringing biologists, chemists, engineers and clinicians with a common interest in tetrapyrroles the conference provides a forum for cross-disciplinary ideas and collaboration. The perspective provided by biologists, chemists, and clinicians working in fields such as newly discovered defects in human porphyrin metabolism, the myriad of strategies for light harvesting in photosynthetic organisms, novel tetrapyrroles that serve as auxiliary chromophores or enzyme cofactors, synthetic strategies in the design of novel tetrapyrrole scaffolds, and tetrapyrrole based cell signaling and regulatory systems, makes this conference unique in the field. Over the years the growing evidence for the role of tetrapyrroles and their reactive intermediates in cell signaling and regulation has been of increasing importance at this conference. The 2010 conference on Chemistry & Biology of Tetrapyrroles will focus on many of these new frontiers as outlined in the preliminary program listed. Speakers will emphasize unpublished results and new findings in the field. The oral sessions will be followed by the highly interactive afternoon poster sessions. The poster sessions provide all conferees with the opportunity to present their latest research and to exchange ideas in a more informal setting. As in the past, this opportunity will continue during the nightly social gathering that takes place in the poster hall following the evening lectures. All conferees are encouraged to submit and present posters. At the conference the best poster in the areas of biology, chemistry and medicine will be selected by a panel of previous conference chairs.

  6. Ultrafast Phenomena 6. Proceedings of the International Conference (6th) Held in Kyoto, Japan on July 12-15, 1988. Springer Series in Chemical Physics, Volume 48

    DTIC Science & Technology

    1988-01-01

    Short pulses with ultrahigh peak powers have been generat,:d in Nd:glavs and Alexandrite using the Chirped Pulse Amplification (CPA) technique. This...Thus it allows the utilization of superior storage energy amplifiers such as Nd:glass, Alexandrite , and Ti:sapphire. Solid-state media doped with...from 7( to 1110 nrn with large bandwidths. One of them, Alexandrite , with a bandwidth covering the 700-800 nm range, has reached a high average power

  7. In-plane magnetization-induced quantum anomalous Hall effect.

    PubMed

    Liu, Xin; Hsu, Hsiu-Chuan; Liu, Chao-Xing

    2013-08-23

    The quantum Hall effect can only be induced by an out-of-plane magnetic field for two-dimensional electron gases, and similarly, the quantum anomalous Hall effect has also usually been considered for systems with only out-of-plane magnetization. In the present work, we predict that the quantum anomalous Hall effect can be induced by in-plane magnetization that is not accompanied by any out-of-plane magnetic field. Two realistic two-dimensional systems, Bi2Te3 thin film with magnetic doping and HgMnTe quantum wells with shear strains, are presented and the general condition for the in-plane magnetization-induced quantum anomalous Hall effect is discussed based on the symmetry analysis. Nonetheless, an experimental setup is proposed to confirm this effect, the observation of which will pave the way to search for the quantum anomalous Hall effect in a wider range of materials.

  8. Geometric spin Hall effect of light with inhomogeneous polarization

    NASA Astrophysics Data System (ADS)

    Ling, Xiaohui; Zhou, Xinxing; Yi, Xunong

    2017-01-01

    The spin Hall effect of light originates from spin-orbit interaction of light, which manifests two types of geometric phases. In this paper, we report the observation of a geometric spin Hall effect by generating a light beam with inhomogeneous polarization distribution. Unlike the previously reported geometric spin Hall effect observed in a tilted beam-detector system, which is believed to result from an effective spin-redirection Berry geometric phase, the geometric spin Hall effect demonstrated here is attributed to an effective, spatially varying Pancharatnam-Berry geometric phase generated by the inhomogeneous polarization geometry. Our further experiments show that the geometric spin Hall effect can be tuned by tailoring the polarization geometry of light, demonstrating the spin states of photons can be steered with a great flexibility.

  9. Construction and Operation of a Differential Hall Element Magnetometer

    NASA Astrophysics Data System (ADS)

    Calkins, Matthew W.; Javernick, Philip D.; Quintero, Pedro A.; Calm, Yitzi M.; Meisel, Mark W.

    2012-02-01

    A Differential Hall Element Magnetometer (DHEM) was constructed to measure the magnetic saturation and coercive fields of small samples consisting of magnetic nanoparticles that may have biomedical applications. The device consists of two matched Hall elements that can be moved through the room temperature bore of a 9 Tesla superconducting magnet. The Hall elements are wired in opposition such that a null response, to within a small offset, is measured in the absence of a sample that may be located on top of one unit. A LabVIEW program controls the current through the Hall elements and measures the net Hall voltage while simultaneously moving the probe through the magnetic field by regulating a linear stepper motor. Ultimately, the system will be tested to obtain a figure of merit using successively smaller samples. Details of the apparatus will be provided along with preliminary data.

  10. Topological insulator in junction with ferromagnets: Quantum Hall effects

    NASA Astrophysics Data System (ADS)

    Chudnovskiy, A. L.; Kagalovsky, V.

    2015-06-01

    The ferromagnet-topological insulator-ferromagnet (FM-TI-FM) junction exhibits thermal and electrical quantum Hall effects. The generated Hall voltage and transverse temperature gradient can be controlled by the directions of magnetizations in the FM leads, which inspires the use of FM-TI-FM junctions as electrical and as heat switches in spintronic devices. Thermal and electrical Hall coefficients are calculated as functions of the magnetization directions in ferromagnets and the spin-relaxation time in TI. Both the Hall voltage and the transverse temperature gradient decrease but are not completely suppressed even at very short spin-relaxation times. The Hall coefficients turn out to be independent of the spin-relaxation time for symmetric configuration of FM leads.

  11. Unconventional quantum Hall effect in Floquet topological insulators.

    PubMed

    Tahir, M; Vasilopoulos, P; Schwingenschlögl, U

    2016-09-28

    We study an unconventional quantum Hall effect for the surface states of ultrathin Floquet topological insulators in a perpendicular magnetic field. The resulting band structure is modified by photon dressing and the topological property is governed by the low-energy dynamics of a single surface. An exchange of symmetric and antisymmetric surface states occurs by reversing the light's polarization. We find a novel quantum Hall state in which the zeroth Landau level undergoes a phase transition from a trivial insulator state, with Hall conductivity [Formula: see text] at zero Fermi energy, to a Hall insulator state with [Formula: see text]. These findings open new possibilities for experimentally realizing nontrivial quantum states and unusual quantum Hall plateaus at [Formula: see text].

  12. Anomalous Hall effect in YIG|Pt bilayers

    SciTech Connect

    Meyer, Sibylle Schlitz, Richard; Geprägs, Stephan; Opel, Matthias; Huebl, Hans; Goennenwein, Sebastian T. B.; Gross, Rudolf

    2015-03-30

    We measure the ordinary and the anomalous Hall effect in a set of yttrium iron garnet|platinum (YIG|Pt) bilayers via magnetization orientation dependent magnetoresistance experiments. Our data show that the presence of the ferrimagnetic insulator YIG leads to an anomalous Hall effect like voltage in Pt, which is sensitive to both Pt thickness and temperature. Interpretation of the experimental findings in terms of the spin Hall anomalous Hall effect indicates that the imaginary part of the spin mixing conductance G{sub i} plays a crucial role in YIG|Pt bilayers. In particular, our data suggest a sign change in G{sub i} between 10 K and 300 K. Additionally, we report a higher order Hall effect contribution, which appears in thin Pt films on YIG at low temperatures.

  13. Experimental evidence for a two-dimensional quantized Hall insulator

    NASA Astrophysics Data System (ADS)

    Hilke, M.; Shahar, D.; Song, S. H.; Tsui, D. C.; Xie, Y. H.; Monroe, Don

    1998-10-01

    The general theoretical definition of an insulator is a material in which the conductivity vanishes at the absolute zero of temperature. In classical insulators, such as materials with a band gap, vanishing conductivities lead to diverging resistivities. But other insulators can show more complex behaviour, particularly in the presence of a high magnetic field, where different components of the resistivity tensor can display different behaviours: the magnetoresistance diverges as the temperature approaches absolute zero, but the transverse (Hall) resistance remains finite. Such a system is known as a Hall insulator. Here we report experimental evidence for a quantized Hall insulator in a two-dimensional electron system-confined in a semiconductor quantum well. The Hall resistance is quantized in the quantum unit of resistance h/e2, where h is Planck's constant and e the electronic charge. At low fields, the sample reverts to being a normal Hall insulator.

  14. A simple method for monitoring mutagenicity of river water. Mutagens in Yodo River system, Kyoto-Osaka

    SciTech Connect

    Sakamoto, Hiroshi; Hayatsu, Hikoya )

    1990-04-01

    Blue cotton is a cotton preparation, bearing copper phthalocyanine trisulfonate as a covalently linked ligand, and is an adsorbent specific for compounds with three or greater number of fused rings. Due to this special property, blue cotton has been used for extracting mutagenic polycyclic compounds from crude materials. In early work, the authors gave a brief account of the results of monitoring river-water mutagenicity with blue cotton. Recently they have improved the quality of the adsorbent; rayon in place of cotton was employed as the support for the ligand, and a more powerful adsorbent, blue rayon, which contains 2-3 times greater amount of the ligand than blue cotton, was prepared. In this paper the authors report the use of the blue-rayon method to detect mutagenic compounds in the Yodo river, which flows through the cities of Kyoto and Osaka and is a major source of drinking water for the 10 million people in the area.

  15. Advances in boron neutron capture therapy (BNCT) at kyoto university - From reactor-based BNCT to accelerator-based BNCT

    NASA Astrophysics Data System (ADS)

    Sakurai, Yoshinori; Tanaka, Hiroki; Takata, Takushi; Fujimoto, Nozomi; Suzuki, Minoru; Masunaga, Shinichiro; Kinashi, Yuko; Kondo, Natsuko; Narabayashi, Masaru; Nakagawa, Yosuke; Watanabe, Tsubasa; Ono, Koji; Maruhashi, Akira

    2015-07-01

    At the Kyoto University Research Reactor Institute (KURRI), a clinical study of boron neutron capture therapy (BNCT) using a neutron irradiation facility installed at the research nuclear reactor has been regularly performed since February 1990. As of November 2014, 510 clinical irradiations were carried out using the reactor-based system. The world's first accelerator-based neutron irradiation system for BNCT clinical irradiation was completed at this institute in early 2009, and the clinical trial using this system was started in 2012. A shift of BCNT from special particle therapy to a general one is now in progress. To promote and support this shift, improvements to the irradiation system, as well as its preparation, and improvements in the physical engineering and the medical physics processes, such as dosimetry systems and quality assurance programs, must be considered. The recent advances in BNCT at KURRI are reported here with a focus on physical engineering and medical physics topics.

  16. Kyoto islet isolation method: the optimized one for non-heart-beating donors with highly efficient islet retrieval.

    PubMed

    Okitsu, T; Matsumoto, S; Iwanaga, Y; Noguchi, H; Nagata, H; Yonekawa, Y; Maekawa, T; Tanaka, K

    2005-10-01

    The availability of pancreata for clinical cadaveric islet transplantation is restricted to non-heart-beating donors (NHBDs) in Japan. This forced us to modify the current standard islet isolation protocol that was made up for brain-dead donors and make it suitable for NHBDs. The Kyoto islet isolation method is the one with induction of several steps based on the ideas both already reported literally and invented originally by ourselves. Using this islet isolation method, we isolated islets from 13 human pancreata of NHBDs and transplanted 11 preparations to six type-1 diabetic patients. The rate to meet release criteria of Edmonton protocol was 84.6%. Establishment of this method allowed us to begin a clinical islet transplantation program in Japan and to continue to perform the preparation of islets from NHBDs with high rate to meet the release criteria of the Edmonton protocol.

  17. Hall viscosity and momentum transport in lattice and continuum models of the integer quantum Hall effect in strong magnetic fields

    NASA Astrophysics Data System (ADS)

    Tuegel, Thomas I.; Hughes, Taylor L.

    2015-10-01

    The Hall viscosity describes a nondissipative response to strain in systems with broken time-reversal symmetry. We develop a method for computing the Hall viscosity of lattice systems in strong magnetic fields based on momentum transport, which we compare to the method of momentum polarization used by Tu et al. [Phys. Rev. B 88, 195412 (2013), 10.1103/PhysRevB.88.195412] and Zaletel et al. [Phys. Rev. Lett. 110, 236801 (2013), 10.1103/PhysRevLett.110.236801] for noninteracting systems. We compare the Hall viscosity of square-lattice tight-binding models in magnetic field to the continuum integer quantum Hall effect (IQHE) showing agreement when the magnetic length is much larger than the lattice constant, but deviation as the magnetic field strength increases. We also relate the Hall viscosity of relativistic electrons in magnetic field (the Dirac IQHE) to the conventional IQHE. The Hall viscosity of the lattice Dirac model in magnetic field agrees with the continuum Dirac Hall viscosity when the magnetic length is much larger than the lattice constant. We also show that the Hall viscosity of the lattice model deviates further from the continuum model if the C4 symmetry of the square lattice is broken to C2, but the deviation is again minimized as the magnetic length increases.

  18. 48 CFR 6101.11 - Conferences; conference memorandum [Rule 11].

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Conferences; conference memorandum . 6101.11 Section 6101.11 Federal Acquisition Regulations System CIVILIAN BOARD OF CONTRACT APPEALS, GENERAL SERVICES ADMINISTRATION CONTRACT DISPUTE CASES 6101.11 Conferences; conference...

  19. Spectral Properties of Fractional Quantum Hall Hamiltonians

    NASA Astrophysics Data System (ADS)

    Weerasinghe, Amila

    The fractional quantum Hall (FQH) effect plays a prominent role in the study of topological phases of matter and of strongly correlated electron systems in general. FQH systems have been demonstrated to show many interesting novel properties such as fractional charges, and are believed to harbor even more intriguing phenomena such as fractional statistics. However, there remain many interesting questions to be addressed in this regime. The work reported in this thesis aims to push the envelope of our understanding of the low-energy properties of FQH states using microscopic principles. In the first part of the thesis, we present a systematic perturbative approach to study excitations in the thin cylinder/torus limit of the quantum Hall states. The approach is applied to the Haldane-Rezayi and Gaffnian quantum Hall states, which are both expected to have gapless excitations in the usual two-dimensional thermodynamic limit. For the Haldane-Rezayi state, we confirm that gapless excitations are present also in the "one-dimensional" thermodynamic limit of an infinite thin cylinder, in agreement with earlier considerations based on the wave functions alone. In contrast, we identify the lowest excitations of the Gaffnian state in the thin cylinder limit, and conclude that they are gapped, using a combination of perturbative and numerical means. We discuss possible scenarios for the cross-over between the two-dimensional and the one-dimensional thermodynamic limit in this case. In the second part of the thesis, we study the low energy spectral properties of positive center-of-mass conserving two-body Hamiltonians as they arise in models of FQH states. Starting from the observation that positive many-body Hamiltonians must have ground state energies that increase monotonously in particle number, we explore what general additional constraints can be obtained for two-body interactions with "center-of-mass conservation" symmetry, both in the presence and absence of particle

  20. Quantum anomalous Hall and quantum spin-Hall phases in flattened Bi and Sb bilayers

    PubMed Central

    Jin, Kyung-Hwan; Jhi, Seung-Hoon

    2015-01-01

    Discovery of two-dimensional topological insulator such as Bi bilayer initiates challenges in exploring exotic quantum states in low dimensions. We demonstrate a promising way to realize the Kane-Mele-type quantum spin Hall (QSH) phase and the quantum anomalous Hall (QAH) phase in chemically-modified Bi and Sb bilayers using first-principles calculations. We show that single Bi and Sb bilayers exhibit topological phase transitions from the band-inverted QSH phase or the normal insulator phase to Kane-Mele-type QSH phase upon chemical functionalization. We also predict that the QAH effect can be induced in Bi or Sb bilayers upon nitrogen deposition as checked from calculated Berry curvature and the Chern number. We explicitly demonstrate the spin-chiral edge states to appear in nitrogenated Bi-bilayer nanoribbons. PMID:25672932

  1. Ozone Induced Impairment of Systemic Metabolic Processes: Influence of Prior Ozone Exposure and Metformin Pre-treatment on Aged Wistar Kyoto (WKY) Rats.

    EPA Science Inventory

    SOT2014 Abstract for presentation: March 23-27, 2014; Phoenix, AZ Ozone Induced Impairment of Systemic Metabolic Processes: Influence of Prior Ozone Exposure and Metformin Pre-treatment on Aged Wistar Kyoto (WKY) Rats. V. Bass, D. Andrews, J. Richards, M. Schladweiler, A. Ledb...

  2. The Promotion of Peace Education through Guides in Peace Museums. A Case Study of the Kyoto Museum for World Peace, Ritsumeikan University

    ERIC Educational Resources Information Center

    Tanigawa, Yoshiko

    2015-01-01

    This paper focuses on how peace education at a peace museum is promoted by a volunteer guide service for visitors. Peace museums are places where many materials related to war and peace history are on display. To support the learning experience of museum visitors, many peace museums in Japan provide a volunteer guide service. The Kyoto Museum for…

  3. Gauge Physics of Spin Hall Effect

    PubMed Central

    Tan, Seng Ghee; Jalil, Mansoor B. A.; Ho, Cong Son; Siu, Zhuobin; Murakami, Shuichi

    2015-01-01

    Spin Hall effect (SHE) has been discussed in the context of Kubo formulation, geometric physics, spin orbit force, and numerous semi-classical treatments. It can be confusing if the different pictures have partial or overlapping claims of contribution to the SHE. In this article, we present a gauge-theoretic, time-momentum elucidation, which provides a general SHE equation of motion, that unifies under one theoretical framework, all contributions of SHE conductivity due to the kinetic, the spin orbit force (Yang-Mills), and the geometric (Murakami-Fujita) effects. Our work puts right an ambiguity surrounding previously partial treatments involving the Kubo, semiclassical, Berry curvatures, or the spin orbit force. Our full treatment shows the Rashba 2DEG SHE conductivity to be instead of −, and Rashba heavy hole instead of −. This renewed treatment suggests a need to re-derive and re-calculate previously studied SHE conductivity. PMID:26689260

  4. On-Chip Microwave Quantum Hall Circulator

    NASA Astrophysics Data System (ADS)

    Mahoney, A. C.; Colless, J. I.; Pauka, S. J.; Hornibrook, J. M.; Watson, J. D.; Gardner, G. C.; Manfra, M. J.; Doherty, A. C.; Reilly, D. J.

    2017-01-01

    Circulators are nonreciprocal circuit elements that are integral to technologies including radar systems, microwave communication transceivers, and the readout of quantum information devices. Their nonreciprocity arises from the interference of microwaves over the centimeter scale of the signal wavelength, in the presence of bulky magnetic media that breaks time-reversal symmetry. Here, we realize a completely passive on-chip microwave circulator with size 1 /1000 th the wavelength by exploiting the chiral, "slow-light" response of a two-dimensional electron gas in the quantum Hall regime. For an integrated GaAs device with 330 μ m diameter and about 1-GHz center frequency, a nonreciprocity of 25 dB is observed over a 50-MHz bandwidth. Furthermore, the nonreciprocity can be dynamically tuned by varying the voltage at the port, an aspect that may enable reconfigurable passive routing of microwave signals on chip.

  5. Photonic versus electronic quantum anomalous Hall effect

    NASA Astrophysics Data System (ADS)

    Bleu, O.; Solnyshkov, D. D.; Malpuech, G.

    2017-03-01

    We derive the diagram of the topological phases accessible within a generic Hamiltonian describing quantum anomalous Hall effect for photons and electrons in honeycomb lattices in the presence of a Zeeman field and spin-orbit coupling (SOC). The two cases differ crucially by the winding number of their SOC, which is 1 for the Rashba SOC of electrons, and 2 for the photon SOC induced by the energy splitting between the TE and TM modes. As a consequence, the two models exhibit opposite Chern numbers ±2 at low field. Moreover, the photonic system shows a topological transition absent in the electronic case. If the photonic states are mixed with excitonic resonances to form interacting exciton-polaritons, the effective Zeeman field can be induced and controlled by a circularly polarized pump. This new feature allows an all-optical control of the topological phase transitions.

  6. Mesoscopic spin Hall effect in semiconductor nanostructures

    NASA Astrophysics Data System (ADS)

    Zarbo, Liviu

    The spin Hall effect (SHE) is a name given to a collection of diverse phenomena which share two principal features: (i) longitudinal electric current flowing through a paramagnetic semiconductor or metallic sample leads to transverse spin current and spin accumulation of opposite sign at opposing lateral edges; (ii) SHE does not require externally applied magnetic field or magnetic ordering in the equilibrium state of the sample, instead it relies on the presence of spin-orbit (SO) couplings within the sample. This thesis elaborates on a new type of phenomenon within the SHE family, predicted in our recent studies [Phys. Rev. B 72, 075361 (2005); Phys. Rev. Lett. 95, 046601 (2005); Phys. Rev. B 72, 075335 (2005); Phys. Rev. B 73 , 075303 (2006); and Europhys. Lett. 77, 47004 (2007)], where pure spin current flows through the transverse electrodes attached to a clean finitesize two-dimensional electron gas (2DEG) due to unpolarized charge current injected through its longitudinal leads. If transverse leads are removed, the effect manifests as nonequilibrium spin Hall accumulation at the lateral edges of 2DEG wires. The SO coupling driving this SHE effect is of the Rashba type, which arises due to structural inversion asymmetry of semiconductor heterostructure hosting the 2DEG. We term the effect "mesoscopic" because the spin Hall currents and accumulations reach optimal value in samples of the size of the spin precession length---the distance over which the spin of an electron precesses by an angle pi. In strongly SO-coupled structures this scale is of the order of ˜100 nm, and, therefore, mesoscopic in the sense of being much larger than the characteristic microscopic scales (such as the Fermi wavelength, screening length, or the mean free path in disordered systems), but still much smaller than the macroscopic ones. Although the first theoretical proposal for SHE, driven by asymmetry in SO-dependent scattering of spin-up and spin-down electrons off impurities

  7. Noncommutative Skyrmions in Quantum Hall Systems

    NASA Astrophysics Data System (ADS)

    Ezawa, Z. F.; Tsitsishvili, G.

    Charged excitations in quantum Hall (QH) systems are noncommutative skyrmions. QH systems represent an ideal system equipped with noncommutative geometry. When an electron is confined within the lowest Landau level, its position is described solely by the guiding center, whose X and Y coordinates do not commute with one another. Topological excitations in such a noncommutative plane are noncommutative skyrmions flipping several spins coherently. We construct a microscopic skyrmion state by applying a certain unitary transformation to an electron or hole state. A remarkable property is that a noncommutative skyrmion carries necessarily the electron number proportional to the topological charge. More remarkable is the bilayer QH system with the layer degree of freedom acting as the pseudospin, where the quasiparticle is a topological soliton to be identified with the pseudospin skyrmion. Such a skyrmion is deformed into a bimeron (a pair of merons) by the parallel magnetic field penetrated between the two layers. Each meron carries the electric charge ±e/2.

  8. Gauge Physics of Spin Hall Effect.

    PubMed

    Tan, Seng Ghee; Jalil, Mansoor B A; Ho, Cong Son; Siu, Zhuobin; Murakami, Shuichi

    2015-12-22

    Spin Hall effect (SHE) has been discussed in the context of Kubo formulation, geometric physics, spin orbit force, and numerous semi-classical treatments. It can be confusing if the different pictures have partial or overlapping claims of contribution to the SHE. In this article, we present a gauge-theoretic, time-momentum elucidation, which provides a general SHE equation of motion, that unifies under one theoretical framework, all contributions of SHE conductivity due to the kinetic, the spin orbit force (Yang-Mills), and the geometric (Murakami-Fujita) effects. Our work puts right an ambiguity surrounding previously partial treatments involving the Kubo, semiclassical, Berry curvatures, or the spin orbit force. Our full treatment shows the Rashba 2DEG SHE conductivity to be [formula in text] instead of [formula in text], and Rashba heavy hole [formula in text] instead of [formula in text]. This renewed treatment suggests a need to re-derive and re-calculate previously studied SHE conductivity.

  9. Gauge Physics of Spin Hall Effect

    NASA Astrophysics Data System (ADS)

    Tan, Seng Ghee; Jalil, Mansoor B. A.; Ho, Cong Son; Siu, Zhuobin; Murakami, Shuichi

    2015-12-01

    Spin Hall effect (SHE) has been discussed in the context of Kubo formulation, geometric physics, spin orbit force, and numerous semi-classical treatments. It can be confusing if the different pictures have partial or overlapping claims of contribution to the SHE. In this article, we present a gauge-theoretic, time-momentum elucidation, which provides a general SHE equation of motion, that unifies under one theoretical framework, all contributions of SHE conductivity due to the kinetic, the spin orbit force (Yang-Mills), and the geometric (Murakami-Fujita) effects. Our work puts right an ambiguity surrounding previously partial treatments involving the Kubo, semiclassical, Berry curvatures, or the spin orbit force. Our full treatment shows the Rashba 2DEG SHE conductivity to be instead of -, and Rashba heavy hole instead of -. This renewed treatment suggests a need to re-derive and re-calculate previously studied SHE conductivity.

  10. Quantum Hall effect on Riemann surfaces

    NASA Astrophysics Data System (ADS)

    Tejero Prieto, Carlos

    2009-06-01

    We study the family of Landau Hamiltonians compatible with a magnetic field on a Riemann surface S by means of Fourier-Mukai and Nahm transforms. Starting from the geometric formulation of adiabatic charge transport on Riemann surfaces, we prove that Hall conductivity is proportional to the intersection product on the first homology group of S and therefore it is quantized. Finally, by using the theory of determinant bundles developed by Bismut, Gillet and Soul, we compute the adiabatic curvature of the spectral bundles defined by the holomorphic Landau levels. We prove that it is given by the polarization of the jacobian variety of the Riemann surface, plus a term depending on the relative analytic torsion.

  11. Spin Hall magnetoresistance at high temperatures

    SciTech Connect

    Uchida, Ken-ichi; Qiu, Zhiyong; Kikkawa, Takashi; Iguchi, Ryo; Saitoh, Eiji

    2015-02-02

    The temperature dependence of spin Hall magnetoresistance (SMR) in Pt/Y{sub 3}Fe{sub 5}O{sub 12} (YIG) bilayer films has been investigated in a high temperature range from room temperature to near the Curie temperature of YIG. The experimental results show that the magnitude of the magnetoresistance ratio induced by the SMR monotonically decreases with increasing the temperature and almost disappears near the Curie temperature. We found that, near the Curie temperature, the temperature dependence of the SMR in the Pt/YIG film is steeper than that of a magnetization curve of the YIG; the critical exponent of the magnetoresistance ratio is estimated to be 0.9. This critical behavior of the SMR is attributed mainly to the temperature dependence of the spin-mixing conductance at the Pt/YIG interface.

  12. Magnetic circuit for hall effect plasma accelerator

    NASA Technical Reports Server (NTRS)

    Manzella, David H. (Inventor); Jacobson, David T. (Inventor); Jankovsky, Robert S. (Inventor); Hofer, Richard (Inventor); Peterson, Peter (Inventor)

    2009-01-01

    A Hall effect plasma accelerator includes inner and outer electromagnets, circumferentially surrounding the inner electromagnet along a thruster centerline axis and separated therefrom, inner and outer magnetic conductors, in physical connection with their respective inner and outer electromagnets, with the inner magnetic conductor having a mostly circular shape and the outer magnetic conductor having a mostly annular shape, a discharge chamber, located between the inner and outer magnetic conductors, a magnetically conducting back plate, in magnetic contact with the inner and outer magnetic conductors, and a combined anode electrode/gaseous propellant distributor, located at a bottom portion of the discharge chamber. The inner and outer electromagnets, the inner and outer magnetic conductors and the magnetically conducting back plate form a magnetic circuit that produces a magnetic field that is largely axial and radially symmetric with respect to the thruster centerline.

  13. Layered quantum Hall insulators with ultracold atoms

    SciTech Connect

    Zamora, A.; Szirmai, G.; Lewenstein, M.

    2011-11-15

    We consider a generalization of the two-dimensional (2D) quantum Hall insulator to a noncompact, non-Abelian gauge group, the Heisenberg-Weyl group. We show that this kind of insulator is actually a layered three-dimensional (3D) insulator with nontrivial topology. We further show that nontrivial combinations of quantized transverse conductivities can be engineered with the help of a staggered potential. We investigate the robustness and topological nature of this conductivity and connect it to the surface modes of the system. We also propose a simple experimental realization with ultracold atoms in 3D confined to a 2D square lattice with the third dimension being mapped to a gauge coordinate.

  14. Universal scaling of the anomalous Hall effect

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoqian; Wang, Wei; Wang, Kejie; Niu, Wei; Lai, Bolin; Maltby, Nick; Yang, Mao; Gao, Ming; Liu, Wenqing; He, Liang; Zhang, Rong; Xu, Yongbing

    2017-04-01

    We have undertaken a detailed study of the magneto-transport properties of ultra-thin Fe films epitaxially grown on GaAs (1 0 0). A metal–semiconductor transition has been observed with a critical thickness of 1.25 nm, which was thought to be related to the thermally activated tunneling between metallic clusters. By fitting {ρ\\text{AH}} versus ρ xx2 with the TYJ equation (Tian et al 2009 Phys. Rev. Lett. 103 087206), we found that the magnetization is negligible for the scaling of the anomalous Hall effect in ultra-thin Fe films. Furthermore, the intrinsic term, which is acquired by the linear fitting of {ρ\\text{AH}} versus ρ xx2 , shows an obvious decrease when the film thickness drops below 1.25 nm, which was thought to be related to the fading of the Berry curvature in the ultra-thin film limit.

  15. Tuning energy relaxation along quantum Hall channels.

    PubMed

    Altimiras, C; le Sueur, H; Gennser, U; Cavanna, A; Mailly, D; Pierre, F

    2010-11-26

    The chiral edge channels in the quantum Hall regime are considered ideal ballistic quantum channels, and have quantum information processing potentialities. Here, we demonstrate experimentally, at a filling factor of ν(L)=2, the efficient tuning of the energy relaxation that limits quantum coherence and permits the return toward equilibrium. Energy relaxation along an edge channel is controllably enhanced by increasing its transmission toward a floating Ohmic contact, in quantitative agreement with predictions. Moreover, by forming a closed inner edge channel loop, we freeze energy exchanges in the outer channel. This result also elucidates the inelastic mechanisms at work at ν(L)=2, informing us, in particular, that those within the outer edge channel are negligible.

  16. Cathode Effects in Cylindrical Hall Thrusters

    SciTech Connect

    Granstedt, E.M.; Raitses, Y.; Fisch, N. J.

    2008-09-12

    Stable operation of a cylindrical Hall thruster (CHT) has been achieved using a hot wire cathode, which functions as a controllable electron emission source. It is shown that as the electron emission from the cathode increases with wire heating, the discharge current increases, the plasma plume angle reduces, and the ion energy distribution function shifts toward higher energies. The observed effect of cathode electron emission on thruster parameters extends and clarifies performance improvements previously obtained for the overrun discharge current regime of the same type of thruster, but using a hollow cathode-neutralizer. Once thruster discharge current saturates with wire heating, further filament heating does not affect other discharge parameters. The saturated values of thruster discharge parameters can be further enhanced by optimal placement of the cathode wire with respect to the magnetic field.

  17. Hall MHD Equilibrium of Accelerated Compact Toroids

    NASA Astrophysics Data System (ADS)

    Howard, S. J.; Hwang, D. Q.; Horton, R. D.; Evans, R. W.; Brockington, S. J.

    2007-11-01

    We examine the structure and dynamics of the compact toroid's magnetic field. The compact toroid is dramatically accelerated by a large rail-gun Lorentz force density equal to j xB. We use magnetic data from the Compact Toroid Injection Experiment to answer the question of exactly where in the system j xB has nonzero values, and to what extent we can apply the standard model of force-free equilibrium. In particular we present a method of analysis of the magnetic field probe signals that allows direct comparison to the predictions of the Woltjer-Taylor force-free model and Turner's generalization of magnetic relaxation in the presence of a non-zero Hall term and fluid vorticity.

  18. Algebraic geometry realization of quantum Hall soliton

    NASA Astrophysics Data System (ADS)

    Abounasr, R.; Ait Ben Haddou, M.; El Rhalami, A.; Saidi, E. H.

    2005-02-01

    Using the Iqbal-Netzike-Vafa dictionary giving the correspondence between the H2 homology of del Pezzo surfaces and p-branes, we develop a way to approach the system of brane bounds in M-theory on S1. We first review the structure of 10-dimensional quantum Hall soliton (QHS) from the view of M-theory on S1. Then, we show how the D0 dissolution in D2-brane is realized in M-theory language and derive the p-brane constraint equations used to define appropriately the QHS. Finally, we build an algebraic geometry realization of the QHS in type IIA superstring and show how to get its type IIB dual. Other aspects are also discussed.

  19. A Preliminary Investigation of Hall Thruster Technology

    NASA Technical Reports Server (NTRS)

    Gallimore, Alec D.

    1997-01-01

    A three-year, NASA/BMDO-sponsored experimental program to conduct performance and plume plasma property measurements on two Russian Stationary Plasma Thrusters (SPTs) has been completed. The program utilized experimental facilitates at the University of Michigan's Plasmadynamics and Electric Propulsion Laboratory (PEPL). The main features of the proposed effort were as follows: We Characterized Hall thruster [and arcjet] performance by measuring ion exhaust velocity with probes at various thruster conditions. Used a variety of probe diagnostics in the thruster plume to measure plasma properties and flow properties including T(sub e) and n(sub e), ion current density and ion energy distribution, and electric fields by mapping plasma potential. Used emission spectroscopy to identify species within the plume and to measure electron temperatures.

  20. 50 KW Class Krypton Hall Thruster Performance

    NASA Technical Reports Server (NTRS)

    Jacobson, David T.; Manzella, David H.

    2003-01-01

    The performance of a 50-kilowatt-class Hall thruster designed for operation on xenon propellant was measured using kryton propellant. The thruster was operated at discharge power levels ranging from 6.4 to 72.5 kilowatts. The device produced thrust ranging from 0.3 to 2.5 newtons. The thruster was operated at discharge voltages between 250 and 1000 volts. At the highest anode mass flow rate and discharge voltage and assuming a 100 percent singly charged condition, the discharge specific impulse approached the theoretical value. Discharge specific impulse of 4500 seconds was demonstrated at a discharge voltage of 1000 volts. The peak discharge efficiency was 64 percent at 650 volts.

  1. Propulsion Instruments for Small Hall Thruster Integration

    NASA Technical Reports Server (NTRS)

    Johnson, Lee K.; Conroy, David G.; Spanjers, Greg G.; Bromaghim, Daron R.

    2001-01-01

    Planning and development are underway for the propulsion instrumentation necessary for the next AFRL electric propulsion flight project, which includes both a small Hall thruster and a micro-PPT. These instruments characterize the environment induced by the thruster and the associated data constitute part of a 'user's manual' for these thrusters. Several instruments probe the back-flow region of the thruster plume, and the data are intended for comparison with detailed numerical models in this region. Specifically, an ion probe is under development to determine the energy and species distributions, and a Langmuir probe will be employed to characterize the electron density and temperature. Other instruments directly measure the effects of thruster operation on spacecraft thermal control surfaces, optical surfaces, and solar arrays. Specifically, radiometric, photometric, and solar-cell-based sensors are under development. Prototype test data for most sensors should be available, together with details of the instrumentation subsystem and spacecraft interface.

  2. Stacking order dependence of inverse spin Hall effect and anomalous Hall effect in spin pumping experiments

    SciTech Connect

    Kim, Sang-Il; Seo, Min-Su; Park, Seung-Young; Kim, Dong-Jun; Park, Byong-Guk

    2015-05-07

    The dependence of the measured DC voltage on the non-magnetic material (NM) in NM/CoFeB and CoFeB/NM bilayers is studied under ferromagnetic resonance conditions in a TE{sub 011} resonant cavity. The directional change of the inverse spin Hall effect (ISHE) voltage V{sub ISHE} for the stacking order of the bilayer can separate the pure V{sub ISHE} and the anomalous Hall effect (AHE) voltage V{sub AHE} utilizing the method of addition and subtraction. The Ta and Ti NMs show a broad deviation of the spin Hall angle θ{sub ISH}, which originates from the AHE in accordance with the high resistivity of NMs. However, the Pt and Pd NMs show that the kinds of NMs with low resistivity are consistent with the previously reported θ{sub ISH} values. Therefore, the characteristics that NM should simultaneously satisfy to obtain a reasonable V{sub ISHE} value in bilayer systems are large θ{sub ISH} and low resistivity.

  3. Lunar & Planetary Science Conference.

    ERIC Educational Resources Information Center

    Warner, Jeffrey L.; And Others

    1982-01-01

    Summaries of different topics discussed at the Lunar and Planetary Science Conference are presented to provide updated information to nonplanetologists. Some topics include Venus, isotopes, chondrites, creation science, cosmic dust, cratering, moons and rings, igneous rocks, and lunar soil. (DC)

  4. Aircraft Engine Emissions. [conference

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.

  5. Tackling conference carbon footprints

    NASA Astrophysics Data System (ADS)

    Grozier, Jim

    2016-12-01

    In reply to Margaret Harris's Lateral Thoughts article "Putting my foot down", which discussed the challenges of attending a conference with a physical disability (October p76) and a subsequent letter by Anna Wood (November p18).

  6. DNA sequencing conference, 2

    SciTech Connect

    Cook-Deegan, R.M.; Venter, J.C.; Gilbert, W.; Mulligan, J.; Mansfield, B.K.

    1991-06-19

    This conference focused on DNA sequencing, genetic linkage mapping, physical mapping, informatics and bioethics. Several were used to study this sequencing and mapping. This article also discusses computer hardware and software aiding in the mapping of genes.

  7. Transport measurements of GaAs/AlGaAs devices in the ``anti-Hall-bar within a Hall bar" geometry

    NASA Astrophysics Data System (ADS)

    Kriisa, Annika; Mani, Ramesh

    2009-11-01

    Hall effect measurements are often carried out in the Hall geometry, which is a thin rectangular plate with current and Hall voltage contacts at the external boundary. The motivation of this study is to further understand the impact on Hall effect when a hole is inserted inside the Hall geometry. One way on conducting this investigation is to superimpose an ``anti-Hall bar'' inside the standard Hall bar, where the anti Hall bar is actually the hole inside the Hall device with contacts on the inside boundary of this hole. This configuration is thought to generate an ordinary Hall effect within the interior boundary. One believes that it might also be possible to simultaneously realize multiple independent Hall effects by injecting multiple currents into the multiply connected device [1]. We have experimentally studied the Hall effect in the doubly connected ``anti-Hall bar within a Hall bar'' geometry fabricated out of the GaAs/AlGaAs semiconductor system, and convey the results in this presentation. [4pt] [1] R. G. Mani and K. von Klitzing, Z. Phys. B 92, 335 (1993).

  8. PREFACE: SQM2007 International Conference on Strangeness in Quark Matter

    NASA Astrophysics Data System (ADS)

    Šafařík, Karel; Šándor, Ladislav; Tomášik, Boris

    2008-04-01

    The International Conference on `Strangeness in Quark Matter' (SQM) was held from 24-29 June 2007 at the Congress Hall of the city cultural centre in the charming mediaeval town of Levoča in north-eastern Slovakia. The Institute of Experimental Physics of the Slovak Academy of Science and the Faculty of Science of the P J Šafárik University in Košice shared the duties of main organizers of the conference. SQM2007 was attended by more than 100 participants from about 20 countries. The natural beauty and the rich cultural and historical monuments of the surrounding Spiš (Scepusium) region created an inspiring setting for the scientific, social and cultural framework of the conference. Continuing the trend started at the SQM2006 conference, heavy flavour physics in heavy-ion collisions was a topic given equal importance in the SQM2007 programme alongside strange quark physics. The Symposium for Students, from Students, organized by Christian Klein-Boesing and Boris Tomášik on the basis of the contributed abstracts, was again an integral and successful part of the conference. The jury, drawn from the organizers, awarded William A Horowitz (Columbia University) the title of best student contribution. The good news is that many students and younger researchers attended the conference. This could not have happened without generous support from our sponsors whom we would like to thank for valuable financial support: CERN, Journal of Physics G, the Prešov self-governing region authorities and the Slovak Physical Society. The kind assistance of the mayor of the town of Levoča is also warmly acknowledged. We would like to extend our gratitude to our colleagues and students from the organizing institutions for their diligent work prior to and during the conference, which ensured that everything worked smoothly. Our special thanks go to our secretaries, Adri Chomičová and Mery Šemš'aková, as well as to the management of the SATEL Hotel in Levoča for their highly

  9. Optical detection of spin Hall effect in metals

    NASA Astrophysics Data System (ADS)

    van T Erve, Olaf; Hanbicki, Aubrey; McCreary, Kathy; Li, Connie; Jonker, Berry

    2015-03-01

    Here we present room temperature measurements of the spin Hall effect in non-magnetic metals such as Pt and β-W using a standard bench top magneto-optic Kerr effect (MOKE) system. With this system, one can readily determine the angular dependence of the induced polarization on the bias current direction, the orientation of the spin Hall induced polarization, and the sign of the spin Hall angle. When a bias current is applied, the spin Hall effect causes electrons of opposite spin to be scattered in orthogonal directions, resulting in a spin accumulation at the surface of the film. The MOKE signal tracks the applied square wave bias current with an amplitude and phase directly related to the spin Hall angle. Using this technique, we show that the spin-Hall angle of β-W is opposite in sign and significantly larger than that of Pt, and follow the structural phase transition from β-W to α-W as the film is annealed through the dependence of the spin Hall angle on crystal structure. We also use this technique to detect spin diffusion from β-W into Al thin films. This work was supported by internal programs at NRL and the NRL Nanoscience Institute

  10. Hall transport of divalent metal ion modified DNA lattices

    SciTech Connect

    Dugasani, Sreekantha Reddy; Lee, Keun Woo; Yoo, Sanghyun; Gnapareddy, Bramaramba; Bashar, Saima; Park, Sung Ha; Kim, Si Joon; Jung, Joohye; Jung, Tae Soo; Kim, Hyun Jae

    2015-06-29

    We investigate the Hall transport characteristics of double-crossover divalent metal ion (Cu{sup 2+}, Ni{sup 2+}, Zn{sup 2+}, and Co{sup 2+})-modified DNA (M-DNA) lattices grown on silica via substrate-assisted growth. The electronic characteristics of the M-DNA lattices are investigated by varying the concentration of the metal ions and then conducting Hall measurements, including resistivity, Hall mobility, carrier concentration, and magneto resistance. The tendency of the resistivity and Hall mobility was to initially decrease as the ion concentration increased, until reaching the saturation concentration (C{sub s}) of each metal ion, and then to increase as the ion concentration increased further. On the other hand, the carrier concentration revealed the opposite tendency as the resistivity and Hall mobility. The specific binding (≤C{sub s}) and the nonspecific aggregates (>C{sub s}) of the ions into the DNA lattices were significantly affected by the Hall characteristics. The numerical ranges of the Hall parameters revealed that the M-DNA lattices with metal ions had semiconductor-like characteristics. Consequently, the distinct characteristics of the electrical transport through M-DNA lattices will provide useful information on the practical use of such structures in physical devices and chemical sensors.

  11. Multiphoton processes: conference proceedings

    SciTech Connect

    Lambropoulos, P.; Smith, S.J.

    1984-01-01

    The chapters of this volume represent the invited papers delivered at the conference. They are arranged according to thermatic proximity beginning with atoms and continuing with molecules and surfaces. Section headings include multiphoton processes in atoms, field fluctuations and collisions in multiphoton process, and multiphoton processes in molecules and surfaces. Abstracts of individual items from the conference were prepared separately for the data base. (GHT)

  12. International Conference on Recent Research and Development in Vocational Education (Adelaide, South Australia, Australia, March 12-19, 1989). Additional Papers.

    ERIC Educational Resources Information Center

    TAFE National Centre for Research and Development, Payneham (Australia).

    The conference recorded in this document covered a wide variety of themes and consisted of keynote addresses, research presentations, and workshops. The following keynote addresses are include: "Some Recent TAFE National Centre Research and Development in Australian Vocational Education" (Hall); "Vocational Teacher Education:…

  13. Proceedings of the Annual Midwest Research-to-Practice Conference in Adult, Continuing, and Community Education (21st, DeKalb, Illinois, October 9-11, 2002).

    ERIC Educational Resources Information Center

    Orem, Richard A., Ed.

    This document contains 41 papers and 11 poster session presentations from a conference on research-to-practice in adult, continuing, and community education. The following are among the papers included: "Learning in a Multicultural Environment" (Mansur Abdullah, Cory Eisenberg, Willard C. Hall Jr., Pauline Valvo); "How to Engage in…

  14. Quantum Hall ferrimagnetism in lateral quantum dot molecules.

    PubMed

    Abolfath, Ramin M; Hawrylak, Pawel

    2006-11-03

    We demonstrate the existence of ferrimagnetic and ferromagnetic phases in a spin phase diagram of coupled lateral quantum dot molecules in the quantum Hall regime. The spin phase diagram is determined from the Hartree-Fock configuration interaction method as a function of electron number N and magnetic field B. The quantum Hall ferrimagnetic phase corresponds to spatially imbalanced spin droplets resulting from strong interdot coupling of identical dots. The quantum Hall ferromagnetic phases correspond to ferromagnetic coupling of spin polarization at filling factors between nu=2 and nu=1.

  15. Quarter-Filled Honeycomb Lattice with a Quantized Hall Conductance

    NASA Astrophysics Data System (ADS)

    Shimshoni, Efrat; Murthy, Ganpathy; Shankar, Ramamurti; Fertig, Herbert

    2012-02-01

    We study a generic two-dimensional hopping model on a honeycomb lattice with strong spin-orbit coupling, without the requirement that the half-filled lattice be a Topological Insulator. For quarter-(or three-quarter) filling, we show that a state with a quantized Hall conductance generically arises in the presence of a Zeeman field of sufficient strength. We discuss the influence of Hubbard interactions and argue that spontaneous ferromagnetism (which breaks time-reversal) will occur, leading to a quantized anomalous Hall effect. G. Murthy, E. Shimshoni, R. Shankar, and H. A. Fertig, arxiv:1108.2010[cond-mat.mes-hall

  16. Kelvin-Helmholtz versus Hall magnetoshear instability in astrophysical flows.

    PubMed

    Gómez, Daniel O; Bejarano, Cecilia; Mininni, Pablo D

    2014-05-01

    We study the stability of shear flows in a fully ionized plasma. Kelvin-Helmholtz is a well-known macroscopic and ideal shear-driven instability. In sufficiently low-density plasmas, also the microscopic Hall magnetoshear instability can take place. We performed three-dimensional simulations of the Hall-magnetohydrodynamic equations where these two instabilities are present, and carried out a comparative study. We find that when the shear flow is so intense that its vorticity surpasses the ion-cyclotron frequency of the plasma, the Hall magnetoshear instability is not only non-negligible, but it actually displays growth rates larger than those of the Kelvin-Helmholtz instability.

  17. Hall Conductivity in the Cosmic Defect and Dislocation Spacetime

    NASA Astrophysics Data System (ADS)

    Ma, Kai; Wang, Jian-Hua; Yang, Huan-Xiong; Fan, Hua-Wei

    2016-10-01

    Influences of topological defect and dislocation on conductivity behavior of charge carries in external electromagnetic fields are studied. Particularly the quantum Hall effect is investigated in detail. It is found that the nontrivial deformations of spacetime due to topological defect and dislocation produce an electric current at the leading order of perturbation theory. This current then induces a deformation on the Hall conductivity. The corrections on the Hall conductivity depend on the external electric fields, the size of the sample and the momentum of the particle.

  18. Effective Field Theory of Fractional Quantized Hall Nematics

    SciTech Connect

    Mulligan, Michael; Nayak, Chetan; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC

    2012-06-06

    We present a Landau-Ginzburg theory for a fractional quantized Hall nematic state and the transition to it from an isotropic fractional quantum Hall state. This justifies Lifshitz-Chern-Simons theory - which is shown to be its dual - on a more microscopic basis and enables us to compute a ground state wave function in the symmetry-broken phase. In such a state of matter, the Hall resistance remains quantized while the longitudinal DC resistivity due to thermally-excited quasiparticles is anisotropic. We interpret recent experiments at Landau level filling factor {nu} = 7/3 in terms of our theory.

  19. Magnet/Hall-Effect Random-Access Memory

    NASA Technical Reports Server (NTRS)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.

    1991-01-01

    In proposed magnet/Hall-effect random-access memory (MHRAM), bits of data stored magnetically in Perm-alloy (or equivalent)-film memory elements and read out by using Hall-effect sensors to detect magnetization. Value of each bit represented by polarity of magnetization. Retains data for indefinite time or until data rewritten. Speed of Hall-effect sensors in MHRAM results in readout times of about 100 nanoseconds. Other characteristics include high immunity to ionizing radiation and storage densities of order 10(Sup6)bits/cm(Sup 2) or more.

  20. Micro-Hall position sensing of magnetic nanowires.

    SciTech Connect

    Mihajlovic, G.; Hoffmann, A.; von Molnar, S.; Materials Science Division; Florida State Univ.

    2009-01-01

    The Hall voltage output of a micro-Hall magnetic sensor depends on the relative position of a magnetic nanowire with respect to its sensing area. Following this idea, we performed analytical calculations which show that, under certain conditions, these devices can track the position of a magnetic nanowire with subnanometer resolution. Our results suggest that micro-Hall sensors can be utilized to provide a direct electronic readout of the position of magnetic nanowires in their applications as biomolecular manipulators or dynamic components in micro- and nanoscale devices.

  1. From University Heights to Cooperstown: Halls of Fame and American Memory

    ERIC Educational Resources Information Center

    Friss, Evan J.

    2005-01-01

    This article examines the development and function of American halls of fame as cultural memory institutions. By comparing the Hall of Fame for Great Americans with the National Baseball Hall of Fame, the author posits that halls of fame illuminate the ways in which cultural memory institutions can, through an archival process, preserve, instill,…

  2. Nuclear Rocket Technology Conference

    NASA Technical Reports Server (NTRS)

    1966-01-01

    The Lewis Research Center has a strong interest in nuclear rocket propulsion and provides active support of the graphite reactor program in such nonnuclear areas as cryogenics, two-phase flow, propellant heating, fluid systems, heat transfer, nozzle cooling, nozzle design, pumps, turbines, and startup and control problems. A parallel effort has also been expended to evaluate the engineering feasibility of a nuclear rocket reactor using tungsten-matrix fuel elements and water as the moderator. Both of these efforts have resulted in significant contributions to nuclear rocket technology. Many successful static firings of nuclear rockets have been made with graphite-core reactors. Sufficient information has also been accumulated to permit a reasonable Judgment as to the feasibility of the tungsten water-moderated reactor concept. We therefore consider that this technoIogy conference on the nuclear rocket work that has been sponsored by the Lewis Research Center is timely. The conference has been prepared by NASA personnel, but the information presented includes substantial contributions from both NASA and AEC contractors. The conference excludes from consideration the many possible mission requirements for nuclear rockets. Also excluded is the direct comparison of nuclear rocket types with each other or with other modes of propulsion. The graphite reactor support work presented on the first day of the conference was partly inspired through a close cooperative effort between the Cleveland extension of the Space Nuclear Propulsion Office (headed by Robert W. Schroeder) and the Lewis Research Center. Much of this effort was supervised by Mr. John C. Sanders, chairman for the first day of the conference, and by Mr. Hugh M. Henneberry. The tungsten water-moderated reactor concept was initiated at Lewis by Mr. Frank E. Rom and his coworkers. The supervision of the recent engineering studies has been shared by Mr. Samuel J. Kaufman, chairman for the second day of the

  3. SOI Hall cells design selection using three-dimensional physical simulations

    NASA Astrophysics Data System (ADS)

    Paun, Maria-Alexandra; Udrea, Florin

    2014-12-01

    The main characteristics of Hall Effect Sensors, based on “silicon-on-insulator” (SOI) structure in the ideal design features, are evaluated by performing three-dimensional physical simulations. A particular Hall shape reproducing an XFAB SOI XI10 integration process is analyzed in details. In order to assess the performance of the considered Hall cell, the Hall voltage, absolute sensitivity and input resistance were extracted through simulations. Electrostatic potential distribution and Hall mobility were also produced through simulations for the considered SOI Hall Basic cell. A comparison between the performance of the same Hall cell manufactured in regular bulk and SOI CMOS technology respectively is given.

  4. PREFACE: The EPS High Energy Particle Physics Conference

    NASA Astrophysics Data System (ADS)

    Barlow, Roger

    2008-03-01

    HEPP2007, the EPS High Energy Particle Physics Conference, was held in Manchester from July 19-26 2007. It brought together 580 delegates across the whole subject: from string theorists to detector technologists, from young postgraduate students to senior professors. Geographically they came from the UK, from the rest of Europe, from North America, and from the rest of the world. It covered the whole spectrum of the subject, not only accelerator-based experiments but also its astrophysical and cosmological aspects. The parallel and plenary talks can be found in these proceedings. A key feature of the conference, as always, was the award of the prizes: this year the EPS prize was awarded to Makoto Kobayashi and Toshihide Maskawa for their explanation of CP violation with a 6 quark model—Kobayashi came to accept it in person. The Gribov medal went to Niklas Beisert, the outreach prize to Richard Jacobsson and Charles Timmermans and the Young Physicist prizer to I Furic, G Gomez-Ceballos and S Menzemer. Parallel sessions were held in Manchester University, and plenary talks were held in the Bridgewater Hall in Manchester Town centre, a magnificent modern venue whose positive and co-operative staff enabled the conference to make the most of the impressive surroundings. We were able to put the hall to its proper purpose one evening with a concert by the Fairey Band—one of the distinctive brass bands who form part of the rich musical tradition of the North of England, and came as something new and different to many of the delegates. The conference ran smoothly and successfully, thanks largely to hard work by the local organising committee who devoted a lot of time to planning, producing ideas, and anticipating potential problems. Many of them were not from Manchester itself but from other universities and laboratories in the North of England, so their dedication was especially appreciated. The EPS committee also played a major part, by the selection of plenary

  5. 9. Interior of Building 1009, view of central hall, looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Interior of Building 1009, view of central hall, looking southeast - Naval Air Station Chase Field, Building 1009, Essex Street, .68 mile South-southeast of intersection of Texas State Highway 202 & Independence Street, Beeville, Bee County, TX

  6. Valleytronics. The valley Hall effect in MoS₂ transistors.

    PubMed

    Mak, K F; McGill, K L; Park, J; McEuen, P L

    2014-06-27

    Electrons in two-dimensional crystals with a honeycomb lattice structure possess a valley degree of freedom (DOF) in addition to charge and spin. These systems are predicted to exhibit an anomalous Hall effect whose sign depends on the valley index. Here, we report the observation of this so-called valley Hall effect (VHE). Monolayer MoS2 transistors are illuminated with circularly polarized light, which preferentially excites electrons into a specific valley, causing a finite anomalous Hall voltage whose sign is controlled by the helicity of the light. No anomalous Hall effect is observed in bilayer devices, which have crystal inversion symmetry. Our observation of the VHE opens up new possibilities for using the valley DOF as an information carrier in next-generation electronics and optoelectronics.

  7. Fractional quantum Hall effect in the absence of Landau levels.

    PubMed

    Sheng, D N; Gu, Zheng-Cheng; Sun, Kai; Sheng, L

    2011-07-12

    It is well known that the topological phenomena with fractional excitations, the fractional quantum Hall effect, will emerge when electrons move in Landau levels. Here we show the theoretical discovery of the fractional quantum Hall effect in the absence of Landau levels in an interacting fermion model. The non-interacting part of our Hamiltonian is the recently proposed topologically non-trivial flat-band model on a checkerboard lattice. In the presence of nearest-neighbouring repulsion, we find that at 1/3 filling, the Fermi-liquid state is unstable towards the fractional quantum Hall effect. At 1/5 filling, however, a next-nearest-neighbouring repulsion is needed for the occurrence of the 1/5 fractional quantum Hall effect when nearest-neighbouring repulsion is not too strong. We demonstrate the characteristic features of these novel states and determine the corresponding phase diagram.

  8. Linear Magnetization Dependence of the Intrinsic Anomalous Hall Effect

    SciTech Connect

    Zeng, C.; Yao, Y.; Niu, Q.; Weitering, Harm H

    2006-01-01

    The anomalous Hall effect is investigated experimentally and theoretically for ferromagnetic thin films of Mn{sub 5}Ge{sub 3}. We have separated the intrinsic and extrinsic contributions to the experimental anomalous Hall effect and calculated the intrinsic anomalous Hall conductivity from the Berry curvature of the Bloch states using first-principles methods. The intrinsic anomalous Hall conductivity depends linearly on the magnetization, which can be understood from the long-wavelength fluctuations of the spin orientation at finite temperatures. The quantitative agreement between theory and experiment is remarkably good, not only near 0 K but also at finite temperatures, up to about -240 K (0.8T{sub c}).

  9. Interior view of hall to bath 1 showing typical doors ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of hall to bath 1 showing typical doors and attic scuttle, facing east. - Albrook Air Force Station, Field Officer's Quarters, West side of Dargue Avenue Circle, Balboa, Former Panama Canal Zone, CZ

  10. 18. VIEW OF STAIRCASE LEADING TO SOCIAL HALL ON CABIN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. VIEW OF STAIRCASE LEADING TO SOCIAL HALL ON CABIN (POOP) DECK, LOCATED IN CENTER OF FORWARD END OF DINING SALOON - Steam Schooner WAPAMA, Kaiser Shipyard No. 3 (Shoal Point), Richmond, Contra Costa County, CA

  11. 9. INTERIOR, VIEW SHOWING MAIN STAIRWAY AND ENTRY HALL THROUGH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. INTERIOR, VIEW SHOWING MAIN STAIRWAY AND ENTRY HALL THROUGH ENTRY INTO PARLOR. TAKEN FROM SOUTHWEST CORNER OF PARLOR, LOOKING NORTHWEST - Farquhar House, 1601 Sandy Spring Road (Route 108), Sandy Spring, Montgomery County, MD

  12. Interior view, stairwell and entrance to the great hall (note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, stairwell and entrance to the great hall (note Boardman Roberts's painting, Great Codifers of Law) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  13. INTERIOR; VIEW OF ENTRY HALL, LOOKING SOUTH. Naval Computer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR; VIEW OF ENTRY HALL, LOOKING SOUTH. - Naval Computer & Telecommunications Area Master Station, Eastern Pacific, Radio Transmitter Facility Lualualei, Marine Barracks, Intersection of Tower Drive & Morse Street, Makaha, Honolulu County, HI

  14. INTERIOR LIBRARY HALL, LOOKING WEST. Oregon Inlet Coast Guard ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR LIBRARY HALL, LOOKING WEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  15. INTERIOR HALL BY TOWER STAIRS, LOOKING SOUTH. Oregon Inlet ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR HALL BY TOWER STAIRS, LOOKING SOUTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  16. INTERIOR TOWER STAIRS HALL, LOOKING NORTH INTO MESS. Oregon ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR TOWER STAIRS HALL, LOOKING NORTH INTO MESS. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  17. INTERIOR TOWER ENTRANCE HALL, LOOKING NORTHWEST. Oregon Inlet Coast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR TOWER ENTRANCE HALL, LOOKING NORTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  18. 20. INTERIOR OF SOUTHERN ROOM. VIEW LOOKING NORTHWEST TOWARD HALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. INTERIOR OF SOUTHERN ROOM. VIEW LOOKING NORTHWEST TOWARD HALL CONNECTING WITH CENTRAL ROOM. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  19. Nonlinear excitation of long-wavelength modes in Hall plasmas

    NASA Astrophysics Data System (ADS)

    Lakhin, V. P.; Ilgisonis, V. I.; Smolyakov, A. I.; Sorokina, E. A.

    2016-10-01

    Hall plasmas with magnetized electrons and unmagnetized ions exhibit a wide range of small scale fluctuations in the lower-hybrid frequency range as well as low-frequency large scale modes. Modulational instability of lower-hybrid frequency modes is investigated in this work for typical conditions in Hall plasma devices such as magnetrons and Hall thrusters. In these conditions, the dispersion of the waves in the lower-hybrid frequency range propagating perpendicular to the external magnetic field is due to the gradients of the magnetic field and the plasma density. It is shown that such lower-hybrid modes are unstable with respect to the secondary instability of the large scale quasimode perturbations. It is suggested that the large scale slow coherent modes observed in a number of Hall plasma devices may be explained as a result of such secondary instabilities.

  20. 15. VIEW SHOWING FRONT OF MESS HALL, LOOKING NORTH. STORE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. VIEW SHOWING FRONT OF MESS HALL, LOOKING NORTH. STORE WORK WAS SUBSEQUENTLY ADDED Marilyn Ziemer, photographer, April 1988 - Los Pinetos Nike Missile Site, Santa Clara Road, Los Angeles National Forest, Sylmar, Los Angeles County, CA

  1. Interior view of entry hall in Communication Center (now Break ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of entry hall in Communication Center (now Break Room and Storage Area), facing north - MacDill Air Force Base, Fire & Guard House, 2709 Florida Keys Avenue, Tampa, Hillsborough County, FL

  2. Transom Profile; Door Elevation; Entrance Hall Ceiling Profile National ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Transom Profile; Door Elevation; Entrance Hall Ceiling Profile - National Home for Disabled Volunteer Soldiers - Battle Mountain Sanitarium, Administration Building, 500 North Fifth Street, Hot Springs, Fall River County, SD

  3. 16. INDEPENDENCE HALL LOOKING SOUTH ON CHESTNUT ST. (horizontal line) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. INDEPENDENCE HALL LOOKING SOUTH ON CHESTNUT ST. (horizontal line) BETWEEN SIXTH (right) AND FIFTH (left) STS. - Independence National Historical Park, Walnut, Sixth, Chestnut & Second Streets, Philadelphia, Philadelphia County, PA

  4. 18. West room, second floor. View looking southeast. Center hall ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. West room, second floor. View looking southeast. Center hall visible through doorway. - Fort Hill Farm, Mansion, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  5. Batch-fabricated high-performance graphene Hall elements

    PubMed Central

    Xu, Huilong; Zhang, Zhiyong; Shi, Runbo; Liu, Honggang; Wang, Zhenxing; Wang, Sheng; Peng, Lian-Mao

    2013-01-01

    Hall elements are by far the most widely used magnetic sensor. In general, the higher the mobility and the thinner the active region of the semiconductor used, the better the Hall device. While most common magnetic field sensors are Si-based Hall sensors, devices made from III-V compounds tend to favor over that based on Si. However these devices are more expensive and difficult to manufacture than Si, and hard to be integrated with signal-processing circuits for extending function and enforcing performance. In this article we show that graphene is intrinsically an ideal material for Hall elements which may harness the remarkable properties of graphene, i.e. extremely high carrier mobility and atomically thin active body, to create ideal magnetic sensors with high sensitivity, excellent linearity and remarkable thermal stability. PMID:23383375

  6. 48. INTERIOR, FIRST FLOOR, ENTRANCE HALL, DETAIL OF BUST OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. INTERIOR, FIRST FLOOR, ENTRANCE HALL, DETAIL OF BUST OF SAMUEL CLEMENTS AND WALL STENCILING - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  7. BLDG 2 INTERIOR SHOWING ARCHES IN HALL BY MAIN ENTRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BLDG 2 INTERIOR SHOWING ARCHES IN HALL BY MAIN ENTRY - Naval Magazine Lualualei, Headquarters Branch, Police Station, Kolekole Road & Constitution Street intersection, north side of main quad, Pearl City, Honolulu County, HI

  8. 50. THIRD FLOOR, HALL, LOOKING SOUTH. Note ceiling extends down ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. THIRD FLOOR, HALL, LOOKING SOUTH. Note ceiling extends down over window case and exterior frieze extends halfway down top light of sash - Robinson-Aiken House, 48 Elizabeth Street, Charleston, Charleston County, SC

  9. Life sciences building, north rear, also showing north hall to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Life sciences building, north rear, also showing north hall to the right, and the library in the center distance. - San Bernardino Valley College, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  10. Basement hall under the northeast part of the building. Live ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Basement hall under the northeast part of the building. Live animal cages and dissection rooms are to the right. Note concrete footings. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  11. 10. Photocopy of photograph (original in Memorial Hall, Deerfield, Massachusetts) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photocopy of photograph (original in Memorial Hall, Deerfield, Massachusetts) VIEW OF MAIN ELEVATION, SHOOTING FROM ROAD THROUGH TREES - Kennedy Farm, Chestnut Grove Road, Samples Manor, Washington County, MD

  12. 1. View looking west, showing side hall facade, wing, porch, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View looking west, showing side hall facade, wing, porch, setting and garage - First Free Will Baptist Church, Parsonage, South side of Dover Road, corner of Blackhall Road, Epsom, Merrimack County, NH

  13. Interior view, anteroom of the postmaster general's reception hall; shown ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, anteroom of the postmaster general's reception hall; shown here are two of the six aluminum statues of postal delivery men - New Post Office Building, Twelfth Street and Pennsylvania Avenue, Washington, District of Columbia, DC

  14. 11. GENERAL VIEW OF MEN'S BATH HALL. Hot Springs ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. GENERAL VIEW OF MEN'S BATH HALL. - Hot Springs National Park, Bathhouse Row, Fordyce Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  15. Survey of the Fermilab D0 detector collision hall

    SciTech Connect

    Babatunde O'Sheg Oshinowo

    2001-07-20

    The Fermilab D0 detector was used for the discovery of the top quark during Run I in 1996. It had been upgraded to exploit the physics potential to be presented by the Main Injector and the Tevatron Collider during Run II. The upgrade of the D0 detector was fully commissioned on March 1, 2001, and thus marked the official start of the Run II experiment. The detector which weighs about 5500 tons, was assembled in the Assembly Hall. Prior to moving the detector into the Collision Hall, the existing survey monuments were densified in the Collision Hall with new monuments. This paper discusses the survey of the Collision Hall using a combination of the Laser Tracker, BETS, V-Stars, and other Optical systems to within the specified accuracy of {+-}0.5mm.

  16. INTERIOR VIEW OF THE HALL. NOTE THE TELEPHONE NICHE, TONGUEANDGROOVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF THE HALL. NOTE THE TELEPHONE NICHE, TONGUE-AND-GROOVE WOOD FLOORING, AND DOUBLE DOOR OF THE LINEN CLOSET. VIEW FACING SOUTHWEST. - Hickam Field, Officers' Housing Type F, 602 Beard Avenue, Honolulu, Honolulu County, HI

  17. INTERIOR VIEW OF SECOND FLOOR HALL. SHOWING THE IRON RAILING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF SECOND FLOOR HALL. SHOWING THE IRON RAILING AND DOUBLE FLUSH WOOD DOORS TO THE LINEN CLOSET. VIEW FACING NORTH. - Hickam Field, Officers' Housing Type C, 208 Second Street, Honolulu, Honolulu County, HI

  18. 27. View east, foreground north facade of Forest Hall, background ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. View east, foreground north facade of Forest Hall, background north facade of Forest East Suites. - Lake Placid Club, Forest Wing, East side of Mirror Lake Drive, North of State Route 86 & Main, North Elba, Essex County, NY

  19. 11. Interior view of former mess hall; showing closed doorway ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Interior view of former mess hall; showing closed doorway to former food storage; near northwest corner of building on main floor; view to east. - Ellsworth Air Force Base, Mess & Administration Building, 1561 Ellsworth Street, Blackhawk, Meade County, SD

  20. 40. VIEW OF TURBINE HALL LOOKING SOUTHWEST AT WESTINGHOUSEPARSONS TURBINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. VIEW OF TURBINE HALL LOOKING SOUTHWEST AT WESTINGHOUSE-PARSONS TURBINE NUMBER 2. THIS UNIT WAS INSTALLED IN 1925. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

  1. 41. VIEW OF TURBINE HALL FROM MEZZANINE LOOKING NORTHWEST AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. VIEW OF TURBINE HALL FROM MEZZANINE LOOKING NORTHWEST AT WESTINGHOUSE-PARSONS TURBOGENERATOR NUMBER 2. THIS UNIT WAS INSTALLED IN 1925. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

  2. 9. FIRST FLOOR, ENTRY HALL, LOOKING SOUTHWEST TOWARDS FRONT ENTRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. FIRST FLOOR, ENTRY HALL, LOOKING SOUTHWEST TOWARDS FRONT ENTRY WITH OPEN DOORWAY TO WINDER STAIRWAY ON RIGHT - Open Gate Farm, House, Ridge Road, 1 mile East of Elephant Road, Perkasie, Bucks County, PA

  3. Model Fractional Quantum Hall States and Jack Polynomials

    SciTech Connect

    Bernevig, B. Andrei; Haldane, F. D. M.

    2008-06-20

    We describe an occupation-number-like picture of fractional quantum Hall states in terms of polynomial wave functions characterized by a dominant occupation-number configuration. The bosonic variants of single-component Abelian and non-Abelian fractional quantum Hall states are modeled by Jack symmetric polynomials (Jacks), characterized by dominant occupation-number configurations satisfying a generalized Pauli principle. In a series of well-known quantum Hall states, including the Laughlin, Read-Moore, and Read-Rezayi, the Jack polynomials naturally implement a ''squeezing rule'' that constrains allowed configurations to be restricted to those obtained by squeezing the dominant configuration. The Jacks presented in this Letter describe new trial uniform states, but it is yet to be determined to which actual experimental fractional quantum Hall effect states they apply.

  4. View of attic space over Renaissance Hall from the east. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of attic space over Renaissance Hall from the east. Central circular walkway provides maintenance access to ceiling lights for the room below. - Masonic Temple, 1 North Broad Street, Philadelphia, Philadelphia County, PA

  5. 13. OBSERVATION HALL ALONG WEST SIDE. DOUBLE DOORS LEAD TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. OBSERVATION HALL ALONG WEST SIDE. DOUBLE DOORS LEAD TO MAIN ROOM. Looking north. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  6. Batch-fabricated high-performance graphene Hall elements.

    PubMed

    Xu, Huilong; Zhang, Zhiyong; Shi, Runbo; Liu, Honggang; Wang, Zhenxing; Wang, Sheng; Peng, Lian-Mao

    2013-01-01

    Hall elements are by far the most widely used magnetic sensor. In general, the higher the mobility and the thinner the active region of the semiconductor used, the better the Hall device. While most common magnetic field sensors are Si-based Hall sensors, devices made from III-V compounds tend to favor over that based on Si. However these devices are more expensive and difficult to manufacture than Si, and hard to be integrated with signal-processing circuits for extending function and enforcing performance. In this article we show that graphene is intrinsically an ideal material for Hall elements which may harness the remarkable properties of graphene, i.e. extremely high carrier mobility and atomically thin active body, to create ideal magnetic sensors with high sensitivity, excellent linearity and remarkable thermal stability.

  7. Hall Determination of Atomic Radii of Alkali Metals

    ERIC Educational Resources Information Center

    Houari, Ahmed

    2008-01-01

    I will propose here an alternative method for determining atomic radii of alkali metals based on the Hall measurements of their free electron densities and the knowledge of their crystal structure. (Contains 2 figures.)

  8. Interior of the second floor dance hall showing tall and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior of the second floor dance hall showing tall and narrow window openings with 10-foot scale near center, looking south. - Bower Building, 409-413 East Weber Avenue, Stockton, San Joaquin County, CA

  9. Insulating to relativistic quantum Hall transition in disordered graphene

    PubMed Central

    Pallecchi, E.; Ridene, M.; Kazazis, D.; Lafont, F.; Schopfer, F.; Poirier, W.; Goerbig, M. O.; Mailly, D.; Ouerghi, A.

    2013-01-01

    Quasi-particle excitations in graphene exhibit a unique behavior concerning two key phenomena of mesoscopic physics: electron localization and the quantum Hall effect. A direct transition between these two states has been found in disordered two-dimensional electron gases at low magnetic field. It has been suggested that it is a quantum phase transition, but the nature of the transition is still debated. Despite the large number of works studying either the localization or the quantum Hall regime in graphene, such a transition has not been investigated for Dirac fermions. Here we discuss measurements on low-mobility graphene where the localized state at low magnetic fields and a quantum Hall state at higher fields are observed. We find that the system undergoes a direct transition from the insulating to the Hall conductor regime. Remarkably, the transverse magneto-conductance shows a temperature independent crossing point, pointing to the existence of a genuine quantum phase transition.

  10. INTERIOR VIEW OF ENTRY HALL. SHOWING THE ORIGINAL ACIDSTAINED CONCRETE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF ENTRY HALL. SHOWING THE ORIGINAL ACID-STAINED CONCRETE FLOOR WITH INCISED STAR PATTERN. VIEW FACING SOUTHEAST. - Hickam Field, Officers' Housing Type C, 208 Second Street, Honolulu, Honolulu County, HI

  11. [Prof. Michiharu Matsuoka, founder of the Department of Orthopaedic Surgery, Kyoto University, and his achievements in orthopaedic surgery in the Meiji Era of Japan (part 1: establishment of the department)].

    PubMed

    Hirotani, Hayato

    2005-09-01

    The Department of Orthopaedic and Musculoskeletal Surgery, Graduate School of Medicine, Kyoto University (formerly the Department of Orthopaedic Surgery, Kyoto Medical School, Kyoto Imperial University) was founded by Imperial Ordinance, Article No. 89 issued on April 23, 1906. On May 4, 1906, Dr. Shinichiro Asahara, Assistant Professor of the Department of Surgery, was appointed as the first director of the Department of Orthopaedic Surgery, Kyoto Medical School, Kyoto Imperial University. Dr. Michiharu Matsuoka, Assistant Doctor of the Department of Surgery, Tokyo Medical School, Imperial University of Tokyo, was appointed Assistant Professor of Surgery, Kyoto Medical School, Kyoto Imperial University in March 1901. From August 1903 to May 1906, he studied orthopaedic surgery in Germany and returned on May 5, 1906. Dr. Matsuoka was appointed as the director and chief of the Department on May 13, 1906 and took over Dr. Asahara's position. On June 18, 1906, Dr. Matsuoka started his clinic and began giving lectures on orthopaedic surgery. This was the first department of orthopaedic surgery among the Japanese medical schools. Dr. Matsuoka was appointed as Professor in 1907. He had to overcome several obstacles to establish the medical department of a new discipline that had never existed in Japanese medical schools. This article discusses Dr. Matsuoka's contributions to establishing and developing orthopaedic surgery in Japan in the Meiji-era.

  12. The Quantum Hall Liquid to Insulator Transitions.

    NASA Astrophysics Data System (ADS)

    Shahar, Dan

    Among the stable phases known to exist in a two dimensional electronic system (2DES), the metallic phase is conspicuously missing. Nonetheless, metallic behavior characterized by finite conductivity as the temperature Tto 0, can be observed at local, isolated points. These are the critical points of quantum phase transitions separating the various stable phases. Although these phase transitions occur at T = 0 and are completely governed by quantum mechanical rules, the theoretical understanding of them is mainly in a critical phenomena framework, that is largely analogous to that used to describe traditional, thermodynamic, phase transitions. The purpose of this dissertation is to report on the identification and characterization of a new family of quantum transitions, between the quantum Hall effect and an insulating phase. In these transitions, the system is driven between a quantum Hall liquid and an insulating phase by changing the externally applied magnetic field (B), or the electronic density, n. We conducted a comprehensive, systematic experiment that virtually encompasses the full range of sample quality available to date. In all, 70 samples were prepared and studied, many at very low T ( >20 mK) and high B (<15.5 T). We studied systematically the transport near the transitions both, in the Ohmic, and non-Ohmic, high current, regimes. For each transition studied a clear, temperature independent, transition B field that separates the QHE liquid state and the insulating phase can be unambiguously determined. We find that despite the large disparity in the properties of our samples, the transport behavior near the transition points is virtually indistinguishable from sample to sample. In particular, the resistivity value at the transition point is found to be universal, and close to the quantum unit of resistance, h/e^2. Also, the behavior of the systems upon approaching the transitions obeys scaling rules with the same critical exponents for all the

  13. Direct Drive Hall Thruster System Development

    NASA Technical Reports Server (NTRS)

    Hoskins, W. Andrew; Homiak, Daniel; Cassady, R. Joseph; Kerslake, Tom; Peterson, Todd; Ferguson, Dale; Snyder, Dave; Mikellides, Ioannis; Jongeward, Gary; Schneider, Todd

    2003-01-01

    The sta:us of development of a Direct Drive Ha!! Thruster System is presented. 13 the first part. a s:udy of the impacts to spacecraft systems and mass benefits of a direct-drive architecture is reviewed. The study initially examines four cases of SPT-100 and BPT-4000 Hall thrusters used for north-south station keeping on an EXPRESS-like geosynchronous spacecraft and for primary propulsion for a Deep Space- 1 based science spacecraft. The study is also extended the impact of direct drive on orbit raising for higher power geosynchronous spacecraft and on other deep space missions as a function of power and delta velocity. The major system considerations for accommodating a direct drive Hall thruster are discussed, including array regulation, system grounding, distribution of power to the spacecraft bus, and interactions between current-voltage characteristics for the arrays and thrusters. The mass benefit analysis shows that, for the initial cases, up to 42 kg of dry mass savings is attributable directly to changes in the propulsion hardware. When projected mass impacts of operating the arrays and the electric power system at 300V are included, up to 63 kg is saved for the four initial cases. Adoption of high voltage lithium ion battery technology is projected to further improve these savings. Orbit raising of higher powered geosynchronous spacecraft, is the mission for which direct drive provides the most benefit, allowing higher efficiency electric orbit raising to be accomplished in a limited period of time, as well as nearly eliminating significant power processing heat rejection mass. The total increase in useful payload to orbit ranges up to 278 kg for a 25 kW spacecraft, launched from an Atlas IIA. For deep space missions, direct drive is found to be most applicable to higher power missions with delta velocities up to several km/s , typical of several Discovery-class missions. In the second part, the status of development of direct drive propulsion power

  14. Dr John Hall (1575-1635) and Shakespeare's medicine.

    PubMed

    Pearce, J M S

    2006-11-01

    The name of Dr John Hall is familiar to students of Shakespeare but less well known to medical biographers. He was born in 1575 and studied at Queen's College, Cambridge, but had no English medical degree. He was not a member of the Royal College of Physicians (founded in 1518). Around 1600, he established himself in Stratford. In June 1607 Hall married Susanna, Shakespeare's elder daughter. He died in 1635, an eminent Stratford physician and herbalist.

  15. The acoustics of a concert hall as a linear problem

    NASA Astrophysics Data System (ADS)

    Lokki, Tapio; Pätynen, Jukka

    2015-01-01

    The main purpose of a concert hall is to convey sound from musicians to listeners and to reverberate the music for more pleasant experience in the audience area. This process is linear and can be represented with impulse responses. However, by studying measured and simulated impulse responses for decades, researchers have not been able to exhaustively explain the success and reputation of certain concert halls.

  16. 2. EXTERIOR OF RUSIN HALL, THE ONLY STRUCTURE TO PREDATED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. EXTERIOR OF RUSIN HALL, THE ONLY STRUCTURE TO PRE-DATED THE WORLD WAR II EXPANSION THAT LED TO THE DEMOLITION OF THE FIRST WARD OF HOMESTEAD, AN AREA KNOWN AS BELOW THE TRACKS. THE BUILDING WAS ORIGINALLY BUILT AS A FRATERNAL HALL FOR RUTHENIAN IMMIGRANTS BY THE RUSSKY-NARODNY-DOM, INC. - U.S. Steel Homestead Works, Auxiliary Buildings & Shops, Along Monongahela River, Homestead, Allegheny County, PA

  17. Exact solutions of the incompressible dissipative Hall magnetohydrodynamics

    SciTech Connect

    Xia, Zhenwei; Yang, Weihong

    2015-03-15

    By using analytical method, the exact solutions of the incompressible dissipative Hall magnetohydrodynamics (MHD) equations are derived. It is found that a phase difference may occur between the velocity and magnetic field fluctuations when the kinetic and magnetic Reynolds numbers are both very large. Since velocity and magnetic field fluctuations are both circular polarized, the phase difference makes them no longer parallel or anti-parallel like that in the incompressible ideal Hall MHD.

  18. Hall effect measurements on InAs nanowires

    SciTech Connect

    Bloemers, Ch.; Grap, T.; Lepsa, M. I.; Moers, J.; Gruetzmacher, D.; Lueth, H.; Trellenkamp, St.; Schaepers, Th.

    2012-10-08

    We have processed Hall contacts on InAs nanowires grown by molecular beam epitaxy using an electron beam lithography process with an extremely high alignment accuracy. The carrier concentrations determined from the Hall effect measurements on these nanowires are lower by a factor of about 4 in comparison with those measured by the common field-effect technique. The results are used to evaluate quantitatively the charging effect of the interface and surface states.

  19. Low-Cost, High-Performance Hall Thruster Support System

    NASA Technical Reports Server (NTRS)

    Hesterman, Bryce

    2015-01-01

    Colorado Power Electronics (CPE) has built an innovative modular PPU for Hall thrusters, including discharge, magnet, heater and keeper supplies, and an interface module. This high-performance PPU offers resonant circuit topologies, magnetics design, modularity, and a stable and sustained operation during severe Hall effect thruster current oscillations. Laboratory testing has demonstrated discharge module efficiency of 96 percent, which is considerably higher than current state of the art.

  20. New pathways towards efficient metallic spin Hall spintronics

    DOE PAGES

    Jungfleisch, Matthias Benjamin; Zhang, Wei; Jiang, Wanjun; ...

    2015-11-16

    Spin Hall effects (SHEs) interconvert spin- and charge currents due to spin- orbit interaction, which enables convenient electrical generation and detection of diffusive spin currents and even collective spin excitations in magnetic solids. Here, we review recent experimental efforts exploring efficient spin Hall detector materials as well as new approaches to drive collective magnetization dynamics and to manipulate spin textures by SHEs. As a result, these studies are also expected to impact practical spintronics applications beyond their significance in fundamental research.