2,653 research outputs found

    Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 4: Open recuperated and bottomed gas turbine cycles

    Get PDF
    Open-cycle recuperated gas turbine plant with inlet temperatures of 1255 to 1644 K (1800 to 2500 F) and recuperators with effectiveness values of 0, 70, 80 and 90% are considered. A 1644 K (2500 F) gas turbine would have a 33.5% plant efficiency in a simple cycle, 37.6% in a recuperated cycle and 47.6% when combined with a sulfur dioxide bottomer. The distillate burning recuperated plant was calculated to produce electricity at a cost of 8.19 mills/MJ (29.5 mills/kWh). Due to their low capital cost 170to200170 to 200 /kW, the open cycle gas turbine plant should see duty for peaking and intermediate load duty

    Cellular distribution and amount of chromogranin A in bovine endocrine pancreas

    Get PDF
    We determined the cellular distribution and the amount of chromogranin A in endocrine cells of bovine pancreas using a polyclonal antibody against bovine adrenomedullary chromogranin A. The relative amounts of chromogranin A in the different cells of the endocrine pancreas were determined by computer-assisted analyses of the optical densities of the immunoreactivities in the stained sections. More than 80% of the immunoreactive chromogranin A was located in the pancreatic B-cells. In immunoblots of acid tissue extracts, only one chromogranin A band (MW 74 KD) was observed. Quantification of the immunoblots revealed that 3 micrograms of chromogranin A and 918 micrograms of insulin were present per gram pancreas (wet weight), equivalent to a molar ratio of 460 mumol chromogranin A per mol insulin

    Hadron Spectroscopy with COMPASS at CERN

    Full text link
    The aim of the COMPASS hadron programme is to study the light-quark hadron spectrum, and in particular, to search for evidence of hybrids and glueballs. COMPASS is a fixed-target experiment at the CERN SPS and features a two-stage spectrometer with high momentum resolution, large acceptance, particle identification and calorimetry. A short pilot run in 2004 resulted in the observation of a spin-exotic state with JPC=1+J^{PC} = 1^{-+} consistent with the debated π1(1600)\pi1(1600). In addition, Coulomb production at low momentum transfer data provide a test of Chiral Perturbation Theory. During 2008 and 2009, a world leading data set was collected with hadron beam which is currently being analysed. The large statistics allows for a thorough decomposition of the data into partial waves. The COMPASS hadron data span over a broad range of channels and shed light on several different aspects of QCD.Comment: 4 pages, 5 figure

    Fermi Surface of KFe2_2As2_2 from Quantum Oscillations in Magnetostriction

    Full text link
    We present a study of the Fermi surface of KFe2_2As2_2 single crystals. Quantum oscillations were observed in magnetostriction measured down to 50 mK and in magnetic fields HH up to 14 T. For HcH \parallel c, the calculated effective masses are in agreement with recent de Haas-van Alphen and ARPES experiments, showing enhanced values with respect to the ones obtained from previous band calculations. For HaH \parallel a, we observed a small orbit at a cyclotron frequency of 64 T, characterized by an effective mass of 0.8me\sim 0.8 m_e, supporting the presence of a three-dimensional pocket at the Z-point.Comment: SCES Conference, Tokyo 201

    Resolving ambiguities in model-independent partial-wave analysis of three-body decay

    Full text link
    Partial wave analysis is an important tool for analyzing large data sets in hadronic decays of light and heavy mesons. It commonly relies on the isobar model, which assumes multihadron final states originate from successive two-body decays of well-known undisturbed intermediate states. Recently, analyses of heavy-meson decays and diffractively produced states have attempted to overcome the strong model dependences of the isobar model. These analyses have overlooked that model-independent, or freed-isobar, partial-wave analysis can break the orthogonality of partial waves and introduce mathematical ambiguities into results. We show how these ambiguities arise and present general techniques for identifying their presence and for correcting for them. We demonstrate these techniques with specific examples in both heavy-meson decay and pion--proton scattering.Comment: 13 pages, 6 figure

    Chromogranin A in the pancreatic islet

    Get PDF
    Chromogranin A (CGA) is the major soluble protein within secretory vesicles of chromaffin cells. A polyclonal antiserum was raised against bovine CGA and characterized in two-dimensional immunoblots. Cellular and subcellular distribution of CGA in bovine pancreatic islet was investigated by immunocytochemistry. At the light microscopic level, CGA-like immunoreactivity was found in the same cells that react with antibodies against insulin, glucagon, and somatostatin. A minority of cells containing pancreatic polypeptide also showed faint immunostaining. At the ultrastructural level (protein A-gold technique), CGA-like immunoreactivity was confined exclusively to the secretory vesicles. Whereas the hormones were localized mainly in the central part of the secretory vesicles, CGA was present predominantly in the periphery. These findings indicate that a CGA-like protein is a regular constituent of the matrix of secretory vesicles in pancreatic endocrine cells

    Towards the identification of a quantum critical line in the (p, B) phase diagram of CeCoIn5

    Full text link
    The low-temperature thermal expansion of CeCoIn5 single crystals measured parallel and perpendicular to magnetic fields B oriented along the c axis yields the volume thermal-expansion coefficient β\beta. Considerable deviations of β(T)\beta(T) from Fermi-liquid behavior occur already within the superconducting region of the (B, T) phase diagram and become maximal at the upper critical field Bc20B^0_{c2}. However, β(T)\beta(T) and the Gr\"uneisen parameter Γ\Gamma are incompatible with a quantum critical point (QCP) at Bc20B^0_{c2}, but allow for a QCP shielded by superconductivity and extending to negative pressures for B<Bc20B < B^0_{c2}. Together with literature data we construct a tentative (p, B, T) phase diagram of CeCoIn5 suggesting a quantum critical line in the (p, B) plane.Comment: 4 pages, 3 figure

    Magnetic properties of single-crystalline CeCuGa3

    Full text link
    The magnetic behavior of single-crystalline CeCuGa3 has been investigated. The compound forms in a tetragonal BaAl4-type structure consisting of rare-earth planes separated by Cu-Ga layers. If the Cu-Ga site disorder is reduced, CeCuGa3 adopts the related, likewise tetragonal BaNiSn3-type structure, in which the Ce ion are surrounded by different Cu and Ga layers and the inversion symmetry is lost. In the literature conflicting reports about the magnetic order of CeCuGa3 have been published. Single crystals with the centrosymmetric structure variant exhibit ferromagnetic order below approx. 4 K with a strong planar anisotropy. The magnetic behavior above the transition temperature can be well understood by the crystal-field splitting of the 4f Hund's rule ground-state multiplet of the Ce ions
    corecore