Interdependence of magnetism and superconductivity in the borocarbide TmNi2B2C

We have discovered a new antiferromagnetic phase in TmNi2B2C by neutron diffraction. The ordering vector is Q_A = (0.48,0,0) and the phase appears above a critical in-plane magnetic field of 0.9 T. The field was applied in order to test the assumption that the zero-field magnetic structure at Q_F = (0.094,0.094,0) would change into a c-axis ferromagnet if superconductivity were destroyed. We present theoretical calculations which show that two effects are important: A suppression of the ferromagnetic component of the RKKY exchange interaction in the superconducting phase, and a reduction of the superconducting condensation energy due to the periodic modulation of the moments at the wave vector Q_A

Magnetic and quadrupolar ordering in TmNi2B2C

We present neutron and high energy synchrotron X ray diffraction studies to show that the anomalous antiferromagnet AF phase diagram of TmNi2B2C in an applied field along [100] is governed by a quadrupolar ordering of the Tm ion

This chart of the China Sea including the Philippina, Mollucca and Banda Islands [cartographic material] : showing at the same time all the tracks into the Pacific Ocean ... /

At head of title: To the Society of managing owners of the ships in the English East India Company's service.; Map of China Sea with relief shown by bathymetric soundings, north west "part of New Holland" shown.; Rex Nan Kivell Collection Map NK 10742.; Library copy has southern sheet only including Indonesia and part of Australia

Flow Characteristics and Sizing of Annular Seat Valves for Digital Displacement Machines

This paper investigates the steady-state flow characteristics and power losses of annular seat valves for digital displacement machines. Annular seat valves are promising candidates for active check-valves used in digital displacement fluid power machinery which excels in efficiency in a broad operating range. To achieve high machine efficiency, the valve flow losses and the required electrical power needed for valve switching should be low. The annular valve plunger geometry, of a valve prototype developed for digital displacement machines, is parametrized by three parameters: stroke length, seat radius and seat width. The steady-state flow characteristics are analyzed using static axi-symmetric computational fluid dynamics. The pressure drops and flow forces are mapped in the valve design space for several different flow rates. The simulated results are compared against measurements using a valve prototype. Using the simulated maps to estimate the flow power losses and a simple generic model to estimate the electric power losses, both during digital displacement operation, optimal designs of annular seat valves, with respect to valve power losses, are derived under several different operating conditions