ROSAT Observations of the Flare Star CC Eri

The flare/spotted spectroscopic binary star CC Eri was observed with the Position Sensitive Proportional Counter (PSPC) on the X-ray satellite ROSAT on 1990 July 9-11 and 1992 January 26-27. During the observations, the source was variable on time scales from a few minutes to several hours, with the X-ray (0.2-2 keV) luminosity in the range $\sim 2.5-6.8\times 10^{29} erg s^{-1}$. An X-ray flare-like event, which has a one hour characteristic rise time and a two hour decay time, was observed from CC Eri on 1990 July 10 16:14-21:34 (UT). The X-ray spectrum of the source can be described by current thermal plasma codes with two temperature components or with a continuous temperature distribution. The spectral results show that plasma at $Te\sim 10^{7}$ K exists in the corona of CC Eri. The variations in the observed source flux and spectra can be reproduced by a flare, adopting a magnetic reconnection model. Comparisons with an unheated model, late in the flare, suggest that the area and volume of the flare are substantially larger than in a solar two ribbon flare, while the electron pressure is similar. The emission measure and temperature of the non-flaring emission, interpreted as the average corona, lead to an electron pressure similar to that in a well-developed solar active region. Rotational modulation of a spot related active region requires an unphysically large X-ray flux in a concentrated area.Comment: 14 pages, compressed and uuencoded postscript file, to be published in MNRA

Squeeze-film gas bearing technology

Squeeze-film bearing is studied to develop a low-friction suspension for the output-axis gimbal of a single-degree-of-freedom gyroscope. Included are a review of pertinent literature, the theory of squeeze-film lubrication, and design elements

On asymptotic analysis of gaseous squeeze-film bearings

Asymptotic analysis for obtaining steady state solution of time dependent gas lubrication equation, of diffusion type, for gaseous squeeze film bearing

On Error Torques of Squeeze-film Cylindrical Journal Bearings

Error torques of squeeze film cylindrical journal bearing

Tuning electronic structure of graphene via tailoring structure: theoretical study

Electronic structures of graphene sheet with different defective patterns are investigated, based on the first principles calculations. We find that defective patterns can tune the electronic structures of the graphene significantly. Triangle patterns give rise to strongly localized states near the Fermi level, and hexagonal patterns open up band gaps in the systems. In addition, rectangular patterns, which feature networks of graphene nanoribbons with either zigzag or armchair edges, exhibit semiconducting behaviors, where the band gap has an evident dependence on the width of the nanoribbons. For the networks of the graphene nanoribbons, some special channels for electronic transport are predicted.Comment: 5 figures, 6 page

Investigation of an axial-excursion transducer for squeeze-film bearings

Resonant frequencies and characteristic bearing cone motion of axial-excursion transducer for squeeze-film gas bearing - drive voltage, preload, bearing mass, and mounting ring effect

The solution of special squeeze film gas bearing problems by an improved numerical technique

Computer program for solving squeeze film gas bearing problem

On the slowly time dependent problem of squeeze film bearings

Time dependency of spherical squeeze-film bearing for use in suspension of precision gyroscope outpu