Reversible recording medium based on optical storage of information, method of reversible recording on such a medium.

A reversible recording medium based on optical storage of at least one item ofinformation within a support material, includes at least one layer of support material having: base molecules able to take, in a local zone, a first collective state of molecules able to generate a first signal of second harmonic characteristic of this first collective state of molecules when excited by electromagnetic reading radiation; the base molecules having the first collective state of molecules able to transform, at least in part, into transformed molecules so as to pass to a second collective state of molecules when excited by electromagnetic writing radiation, the molecules having the second collective state of molecules able to generate a second signal of second harmonic characteristic of this second collective state of molecules when excited by the electromagnetic reading radiation. The molecules exhibit a molecular structure based on a coumarin skeleton of Formula (I)

Reversible Two-Photon Optical Data Storage in Coumarin-Based Copolymers

A functionalized polymer film allowing for a complete and straightforward second-harmonic generation (SHG)-assisted high-contrast writing?reading?erasing?writing sequence is proposed. The whole process is supported by the reversible photoinduced dimerization of a coumarin chromophore and enables efficient optical data storage that can be detected only by SHG imaging

Precise microwave characterization of MgO substrates for HTS circuits with superconducting post dielectric resonator

Accurate data of complex permittivity of dielectric substrates are needed for efficient design of HTS microwave planar circuits. We have tested MgO substrates from three different manufacturing batches using a dielectric resonator with superconducting parts recently developed for precise microwave characterization of laminar dielectrics at cryogenic temperatures. The measurement fixture has been fabricated using a SrLaAlO3 post dielectric resonator with DyBa2Cu3O7 end plates and silver-plated copper sidewalls to achieve the resolution of loss tangent measurements of 2 {\times} 10-6. The tested MgO substrates exhibited the average relative permittivity of 9.63 and tan {\delta} from 3.7 {\times} 10-7 to 2 {\times} 10-5 at frequency of 10.5 GHz in the temperature range from 14 to 80 K.Comment: 6 pages, 8 figures, 3 table

Influence of roughness on ZDDP tribofilm formation in boundary lubricated fretting

Influence of initial surface topography on tribofilm formation in ZDDP lubricated contact was analysed. A small displacement fretting tests with sinusoidal motion were carried out in classical sphere/plane configuration. A range of surfaces with different initial roughness were prepared by milling and grinding processes. Tests were carried out using variable displacement method where amplitude of imposed displacement was gradually increased after every 1000 cycles from 2 to 30 µm. The surfaces after tribological tests were measured by interferometric profiler. Main findings confirm that initial roughness has a significant influence on antiwear tribofilm formation in boundary lubricated contact. Tribofilm form faster and require less energy to activate in case of rough surface obtained by milling process than in case of smooth grinded surface. However, in contact lubricated by ZDDP additive a significant transfer of material occurred from plane to sphere specimen

The Effect of Lifting Straps on Deadlift Performance in Females

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Effect of poling in Polymers Containing Azobenzene Push–Pull Chromophores on nonlinear optic of second and third order

International audienc

Classical field theory on Lie algebroids: Variational aspects

The variational formalism for classical field theories is extended to the setting of Lie algebroids. Given a Lagrangian function we study the problem of finding critical points of the action functional when we restrict the fields to be morphisms of Lie algebroids. In addition to the standard case, our formalism includes as particular examples the case of systems with symmetry (covariant Euler-Poincare and Lagrange Poincare cases), Sigma models or Chern-Simons theories.Comment: Talk deliverd at the 9th International Conference on Differential Geometry and its Applications, Prague, September 2004. References adde