We use the microlensing variability observed for nine gravitationally lensed quasars to show that the accretion disk size at 2500Å is related to the black hole mass by log(R2500/cm) = (15.6± 0.2) + (0.54± 0.28) log(MBH/10M⊙). This scaling is consistent with the expectation from thin disk theory (R ∝ M BH), but it implies that black holes radiate with relatively low efficiency, log(η) = −1.29 ± ...

Using a rotating vitreous carbon disk electrode, the kinetic parameters for chlorine reduction in an AlCl3 KCl-NaC1 (57.5-12.5-30 mol g%) melt were determined. It was found that the reduction of chlorine occurs according to the paths: C1 2 + e C1 + Clad s ads with the first step being most probably rate determining. The apparent exchange currents were (1 ± 0.15)10 -4A/cm 2 at 130 °C and (2.1 ± ...

BACKGROUND AND PURPOSE Data on the association between vertebral endplate changes and low back pain are contradictory. This study was designed to assess whether this association exists among Southern European subjects. MATERIALS AND METHODS Patients in this study serving as cases were 35-50 years of age with low back pain lasting >90 days, for whom a lumbar MR imaging had been prescribed. Con...

Minimizing power consumption is important for mobile computers, and disks consume a signi cant portion of system-wide power. There is a large di erence in power consumption between a disk that is spinning and one that is not, so systems try to keep the disk spinning only when it must. The system must trade o between the power that can be saved by spinning the disk down quickly after each access...

We present observations of CO overtone bandhead emission toward four massive Young Stellar Objects (spectral type O6–B5). The high signal-to-noise ratio K-band spectra were obtained with VLT-ISAAC at a resolution ∆v = 30 km s, sufficient to resolve the bandheads, but not the individual J-lines. We are able to explain the shape of the lines by assuming a simple isothermal keplerian disk model se...

We report on ASCA observations of the low mass X-ray binaries GX 354-0 and KS 1731-260. The spectrum of GX 354-0 is best described as a power-law or a Comptonized spectrum with τ ∼ 5 and kT∼ 8 keV and a residual at ∼ 6.5 keV. The residual may be a disk reflection or a Compton broadened Gaussian line from the hot inner ADAF-like coronal region. The absorption column density to the source is 2.9 ...

Absorption lines of interstellar molecular hydrogen in the far ultraviolet (FUV) have been observed in the spectrum of the O9.5 halo star HD 93521, located some 1500 pc from the Galactic plane. During the second ORFEUS-SPAS mission a spectrum with the Echelle spectrometer has been recorded with a total integration time of 1740 s. The resolution achieved was about λ/∆λ ≥ 10.000 with a signal-to-...

The Red Sea Alcyonarian Heteroxeniafuscescens (Ehrb.) consists of a pinkish brown fleshy syndete up to 5 cm. in length, firmly attached to a stone or dead coral, from which grows a mass of autozooids with columns 2-4 cm. long and 2-3 mm. in diameter (Fig. 1). The first physiological observations on a xenid were made by Keller (1883) on a brown species from Suez that he considered to be H. fusce...

Three recent surveys of 21-cm line emission in the Galactic plane, combining single dish and interferometer observations to achieve resolution of 1 to 2, ∼ 1 km s, and good brightness sensitivity, have provided some 650 absorption spectra with corresponding emission spectra for study of the distribution of warm and cool phase HI in the interstellar medium. These emission-absorption spectrum pai...

Probing the gas and dust in proto-planetary disks is central for understanding the process of planet formation. In disks surrounding solar type protostars, the bulk of the disk mass resides in the outer midplane, which is cold (≤20 K), dense (≥ 107 cm−3) and depleted of CO. Observing the disk midplane has proved, therefore, to be a formidable challenge. Ceccarelli et al. (2004) detected H2D emi...