In the title compound, C(16)H(12)O(2), the non-H atoms are coplanar with a mean r.m.s. deviation of 0.0260 (2) Å. The deviations of the bond angles from normal values at the indenyl junction C atom and the indenyl bridgehead C atom nearest the junction are imposed by the five-membered ring geometry. Due to conjugation, the single bond linking the two ring systems [1.455 (3) Å] is significantly ...

In nonequilibrium states, currents are produced by irreversible processes that take a system toward the equilibrium state, where the current vanishes. We demonstrate, in a general setting, that superstatistics arises when the system relaxes to a (stationary) quasiequilibrium state instead, where only the mean current vanishes because of fluctuations. In particular, we show that a current with g...

where Bp(t) is the ball of radius t centered at p and Bp (t) is the portion of the ball lying inside the sphere SR . Our goal is to show that, up to a negligible term, a similar formula holds for any hypersurface S in Rn, the factor 1/R being replaced with the mean curvature of the hypersurface. We briefly recall what mean curvature is. Let S be a hypersurface of class C2 in Euclidean n-space R...

SENSE MODE AND COUPLING IN A VIGILANCE TASK

We discuss the classical motion of a spring of arbitrary mass coupled to two arbitrary massive blocks attached at its ends. A general approach to the problem is presented and some general results are obtained. Examples for which a simple elastic function can be inferred are discussed and the normal modes and normal frequencies obtained. An approximation procedure to the evaluation of the normel...