Preparations of methoxynitrophenazines and their photoconductivities

Eight methoxynitrophenazines with a methoxy group at the 1 or 2 position and a nitro group at the 6-, 7-, 8- or 9-position of the phenazine ring 1,6, 1,7. 1,8, 1,9, 2,6, 2,7, 2,8 and 2,9 were prepared and their photocurrents were measured by illuminating the surface-type cell with white light from a W lamp under a N atmosphere at room temp. The photocurrents of 1-nitrophenazine 6 and 2-nitrophenazine 7 are compared with those of the methoxynitrophenazines. The photocurrent (i sub p) increases with increasing light intensity (I), thus satisfying log i varies as n log I. The n values are 0.5-1.0. When the nitro group is located at the beta-position of the phenazine ring, the photocurrent becomes larger owing to the electron withdrawing property of the nitro group. On the other hand, the photocurrents of phenazines with the nitro group at the Alpha-position are extremely small. The photoconductivities of methoxynitrophenazines are lower in air

Star Formation Rate from Dust Infrared Emission

We examine what types of galaxies the conversion formula from dust infrared (IR) luminosity into the star formation rate (SFR) derived by Kennicutt (1998) is applicable to. The ratio of the observed IR luminosity, $L_{\rm IR}$, to the intrinsic bolometric luminosity of the newly (\la 10 Myr) formed stars, $L_{\rm SF}$, of a galaxy can be determined by a mean dust opacity in the interstellar medium and the activity of the current star formation. We find that these parameters area being $0.5 \le L_{\rm IR}/L_{\rm SF} \le 2.0$ is very large, and many nearby normal and active star-forming galaxies really fall in this area. It results from offsetting two effects of a small dust opacity and a large cirrus contribution of normal galaxies relative to starburst galaxies on the conversion of the stellar emission into the dust IR emission. In conclusion, the SFR determined from the IR luminosity under the assumption of $L_{\rm IR}=L_{\rm SF}$ like Kennicutt (1998) is reliable within a factor of 2 for all galaxies except for dust rich but quiescent galaxies and extremely dust poor galaxies.Comment: Accepted by ApJL: 6 pages (emulateapj5), 2 figures (one is an extra figure not appeared in ApJL

Effects of various additives on sintering of aluminum nitride

Effects of thirty additives on sintering A/N were investigated. The addition of alkali earth oxides and rare earth oxides gave fully densified aluminum nitride. This is due to the formation of nitrogen-containing aluminate liquid in the system aluminum nitride-alkali earth oxides or rare earth oxides. Microstructural studies of the sintered specimens with the above two types of additives suggested that the densification was due to the liquid phase sintering. Additions of silicon compounds resulted in poor densification by the formation of highly refractory compounds such as A/N polytypes

Altitude variations of cosmic-ray soft and hard components observed by airborne detectors

The altitude variations of cosmic-ray total and hard components were measured up to 12,000 m on board a jet liner over Japan island on December, 1981. Observed results together with soft component are presented comparing with the model calculations through the atmosphere by applying the hadronic cascade

Pattern-recalling processes in quantum Hopfield networks far from saturation

As a mathematical model of associative memories, the Hopfield model was now well-established and a lot of studies to reveal the pattern-recalling process have been done from various different approaches. As well-known, a single neuron is itself an uncertain, noisy unit with a finite unnegligible error in the input-output relation. To model the situation artificially, a kind of 'heat bath' that surrounds neurons is introduced. The heat bath, which is a source of noise, is specified by the 'temperature'. Several studies concerning the pattern-recalling processes of the Hopfield model governed by the Glauber-dynamics at finite temperature were already reported. However, we might extend the 'thermal noise' to the quantum-mechanical variant. In this paper, in terms of the stochastic process of quantum-mechanical Markov chain Monte Carlo method (the quantum MCMC), we analytically derive macroscopically deterministic equations of order parameters such as 'overlap' in a quantum-mechanical variant of the Hopfield neural networks (let us call "quantum Hopfield model" or "quantum Hopfield networks"). For the case in which non-extensive number $p$ of patterns are embedded via asymmetric Hebbian connections, namely, $p/N \to 0$ for the number of neuron $N \to \infty$ ('far from saturation'), we evaluate the recalling processes for one of the built-in patterns under the influence of quantum-mechanical noise.Comment: 10 pages, 3 figures, using jpconf.cls, Proc. of Statphys-Kolkata VI

Variation of the broad X-ray iron line in MCG-6-30-15 during a flare

We report results on the broad iron emission line of the Seyfert galaxy MCG-6-30-15, obtained from the second long ASCA observation in 1997. The time-averaged profile of the broad line is very similar to that seen with ASCA in 1994, so confirming the detailed model fit then obtained. A bright flare is seen in the light curve, during which the continuum was soft. At that time the emission line peaks around 5 keV and most of its emission is shifted below 6 keV with no component detected at 6.4 keV (EW<60 eV). This can be interpreted as the result of an extraordinarily large gravitational redshift due to a dominant flare occurring very close to the black hole at a radius of <5m.Comment: 5 pages, accepted or publication in MNRAS Letter