Process of changing the refractive index of a composite containing a polymer and a compound having large dipole moment and polarizability and applications thereof

Fused ring bridge, ring locked dyes that form thermally stable photorfractive compositions. The fused ring bridge structures are .pi.-conjugated bonds in benzene-, naphthalene- or anthracene-derived fused ring systems that connect donor and acceptor groups. The donor and acceptor groups contribute to a high molecular dipole moment and linear polarizability anisotropy. The polarization characteristics of the dye molecules are stabilized since the bonds in the fused ring bridge are not susceptible to rotation, reducing the opportunity for photoisomerization. The dyes are compatible with polymeric compositions, including thermoplastics. The dyes are electrically neutral but have charge transport, electronic and orientational properties such that upon illumination of a composition containing the dye, the dye facilitates refractive index modulation and a photorefractive effect that can be utilized advantageously in numerous applications such as in optical quality devices and biological imaging

Thermally stable molecules with large dipole moments and polarizabilities and applications thereof

Disclosed are fused ring bridge, ring-locked dyes that form thermally stable photorefractive compositions. The fused ring bridge structures are .pi.-conjugated bonds in benzene-, naphthalene- or anthracene-derived fused ring systems that connect donor and acceptor groups. The donor and acceptor groups contribute to a high molecular dipole moment and linear polarizability anisotropy. The polarization characteristics of the dye molecules are stabilized since the bonds in the fused ring bridge are not susceptible to rotation, reducing the opportunity for photoisomerization. The dyes are compatible with polymeric compositions, including thermoplastics. The dyes are electrically neutral but have charge transport, electronic and orientational properties such that upon illumination of a composition containing the dye, the dye facilitates refractive index modulation and a photorefractive effect that can be utilized advantageously in numerous applications such as in optical quality devices and biological imaging

Metal hydride hydrogen storage and compression systems for energy storage technologies

Along with a brief overview of literature data on energy storage technologies utilising hydrogen and metal hydrides, this article presents results of the related R&D activities carried out by the authors. The focus is put on proper selection of metal hydride materials on the basis of AB5- and AB2-type intermetallic compounds for hydrogen storage and compression applications, based on the analysis of PCT properties of the materials in systems with H2 gas. The article also presents features of integrated energy storage systems utilising metal hydride hydrogen storage and compression, as well as their metal hydride based components developed at IPCP and HySA Systems

Design, physics, and applications of photorefractive polymers

The subject of this dissertation is design, physics, and applications of organic photorefractive polymers which are a recently discovered new class of multifunctional polymeric composites suitable for real-time holographic recording. Design principles of amorphous guest-host photorefractive polymers are described, and their performance is investigated. Also, the use of these materials as recording media in dynamic holographic applications is evaluated. Diffraction efficiency of η ∼ 86%, limited only by absorption and reflection losses, two-beam coupling net gain coefficient of Γ = 200 cm⁻¹, and light-induced refractive index modulations as high as Δn =7x10⁻³ are demonstrated. Hologram growth rates of the order of 500 ms are observed with recording light intensities > 10 mW/cm² using either low-power laser diodes (675 nm) or a HeNe laser (633 nm). The materials have been synthesized that show good sensitivity in red and near-infrared part of the light spectrum. Physical mechanisms leading to high performance of photorefractive polymeric composites and the influence of the polymer composite structure on optical performance are investigated. The experimental results are compared with a phenomenological model based on Kukhtarev's equations. Experiments showing possible applications of PR polymers, such as dynamic time-average interferometry and document security verification are demonstrated

Study of hydrogen storage and electrochemical properties of AB2-typeTi0.15Zr0.85La0.03Ni1.2Mn0.7V0.12Fe0.12alloy

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