64,809 research outputs found
The impact of E × B shear on microtearing based transport in spherical tokamaks
No full textElectromagnetic microtearing modes (MTMs) have been observed in many different spherical tokamak (ST) regimes. Understanding how these and other electromagnetic modes nonlinearly saturate is likely critical in understanding the confinement of a high beta ST. Equilibrium E x B sheared flows have sometimes been found to significantly suppress low beta ion scale transport in both gyrokinetic simulations and in experiment. This work aims to understand the conditions under which E x B sheared flow impacts on the saturation of MTM simulations, as there have been examples where it does (Guttenfelder et al 2012 Phys. Plasmas 19 056119) and does not (Doerk et al 2012 Phys. Plasmas 19 055907) have a considerable effect. Two experimental regimes are examined from MAST and NSTX, on surfaces that have unstable MTMs. The MTM driven transport on a local flux surface in MAST is shown to be more resilient to suppression via E x B shear, compared to the case from NSTX where the MTM transport is found to be significantly suppressed. This difference in the response to flow shear is explained through the impact of magnetic shear, s, on the MTM linear growth rate dependence on ballooning angle, theta 0. At low s, the growth rate depends weakly on theta 0, but at higher s, the MTM growth rate peaks at theta 0 = 0, with regions of stability at higher theta 0. Equilibrium E x B sheared flows act to advect the theta 0 of a mode in time, providing a mechanism to reduce the linear drive and suppress the transport from modes where the growth rate is strongly peaked in theta 0 (Roach et al 2009 Plasma Phys. Control. Fusion 51 124020). Bicoherence analysis demonstrates that with the inclusion of E x B shear there is a more effective coupling between the linearly driven drift-waves responsible for transport and zonal modes, which enhances damping. The dependence of gamma MTM on theta 0 is in qualitative agreement with a recent theory (Hardman et al Plasma Phys. Control. Fusion 65 045011) at low beta when q similar to 1, but the agreement worsens at higher q where the theory breaks down. At higher s, MTMs drive more stochastic transport due a stronger overlap of magnetic islands centred on neighbouring rational surfaces, but equilibrium E x B shear acts to mitigate this. This is especially critical towards the plasma edge where s can be larger and where the total stored energy in the plasma is more sensitive to the local gradients. This work highlights the important role of the safety factor profile in determining the impact of equilibrium E x B shear on the saturation level of MTM turbulence
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Crusading, chivalry and the Saracen world in insular romance
No full textA to M (Part 1 of 2), circa 2003-2019, undated
No full textArtists prominently represented in this box include Yvonne Catchings, Stan Dolega, Ernest Hardman, Carole Harris, Al Loving, and James Malone. In addition, the "Hardman, Ernest" file contains digital material transferred off a CD-R labeled "Hardman". The digital material consists of biographical notes about the artist, a black and white image of his work "Last Supper", and a presentation by Shirley Woodson titled "Painting Traditions in Detroit: Influences and Interpretation".
Finally, the "Murrary, Robert" file is partially in French
Thermal expansion anomalies of R(Fe, M)(12) (R=Y, Nd; M=Mo and Si)
No full textStructural and thermal-expansion anomaly studies on R(Fe,M)(12) (R=Nd and and Y, M=Mo and Si) compounds were performed by x-ray diffraction. Mo atoms occupy the 8i site. While Si atoms occupy the 8f and 8j sites but not the 8i site. Thermal-expansion anomaly shows only in ab plane in the Mo compounds, while becomes very weak and along with only the c axis in the Si compounds. The anomaly was attributed to the contribution of the interactions of short Fe-Fe distances similar to the previous explanation on other R-Fe intermetallics and that of other strongly positive interactions such as 8j-8j. (c) 2005 American Institute of Physics.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000230168300025&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, AppliedSCI(E)EICPCI-S(ISTP)
Letter from Thomas R. Bodine, American Friends Service Committee Seattle office, to Mary M. Kimber, May 25, 1942
No full textLetter from Thomas R. Bodine to Mary M. Kimber, asking Kimber to visit individuals from the Puget Sound area incarcerated at Pinedale Assembly Center: Rev. Daisuke Kitigawa, Waichi Oyanagi, Chisako Higuchi, Mutsuo Hasiguchi and Mrs. Matsuoka, Makato Kobukata, the Hirabayashi family, and Violet Yokoyama. A note in pencil at the top of the page: "Burcham." A response letter from Grace and Calvin Coke to Thomas R. Bodine is found in item: chs_ms840_0306.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
Prediction of fraction of inspired oxygen to achieve a desired arterial partial pressure of oxygen
No full text[No abstract available]ABIZANDA R, 1981, INTENS CARE MED, V7, P247, DOI 10.1007-BF01702629; Hardman JG, 2010, AM J RESP CRIT CARE, V182, P435; OGAWA S, 1989, CRIT CARE MED, V17, P1191, DOI 10.1097-00003246-198911000-000180
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Liftings for noncomplete probability spaces
No full textThe current state of knowledge concerning liftings for noncomplete probability spaces is discussed. This is a somewhat expanded version of the author's talk given at the 1991 Summer Conference on General Topology and Applications in Honor of Mary Ellen Rudin and Her Work.PT: S; CR: BURKE MR, IN PRESS P AM MATH S BURKE MR, 1991, ISRAEL J MATH, V73, P33 BURKE MR, 1992, ISRAEL J MATH, V79, P289 CARLSON T, THEOREM LIFTING CHRISTENSEN JPR, 1974, TOPOLOGY BOREL STRUC FREMLIN DH, 1989, HDB BOOLEAN ALGEBRAS, P877 INOESCUTULCEA A, 1966, 5TH P BERK S MATH ST, V2 IONESCUTULCEA A, 1967, CONTRIBUTIONS PROB 1, P63 IONESCUTULCEA A, 1969, TOPICS THEORY LIFTIN JECH TJ, 1978, SET THEORY JOHNSON RA, 1980, P AM MATH SOC, V80, P234 JUST W, IN PRESS T AM MATH S KUPKA J, 1983, INDIANA U MATH J, V32, P717 LOSERT V, 1983, LNM, V1080, P95 MAHARAM D, 1958, P AM MATH SOC, V9, P987 SHELAH S, 1983, ISRAEL J MATH, V45, P90 TALAGRAND M, 1982, P AM MATH SOC, V84, P379 VONNEUMANN J, 1931, CRELLES J MATH, V165, P109; NR: 18; TC: 0; J9: ANN N Y ACAD SCI; PG: 4; GA: BZ86BSource type: Electronic(1
Preparation of (R)-2-chloro-1-(m-chlorophenyl)ethanol by Lipozyme TL IM-catalyzed second resolution
No full text(R)-2-Chloro-1-(m-chlorophenyl)ethanol, a precursor of (R)-3-chlorostyrene oxide which is the key chiral intermediate for the preparation of several beta 3-adrenergic receptor agonists was prepared in 40% yield and 99% ee by the Lipozyme TL IM-catalyzed second resolution of the corresponding racemate in the presence of vinyl acetate. (C) 2012 Shi Wen Xia. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved
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