Search results for "OPTICS"
showing 10 items of 10033 documents
Functional Hybrid Materials Containing Polypyrrole and Polyoxometalate Clusters: Searching for High Conductivities and Specific Charges
2002
Spectrally selective holographic optical elements based on a thick polymer medium with diffusional amplification
2000
A thick rigid polymer recording medium with self-amplification of holograms owing to diffusion of phenanthrenequinone molecules was used to find efficient holographic optical elements with high-spectral-selectivity interference filters and multiple demultiplexers. Several examples of practical applications are briefly described in this paper, showing the benefits of such optical elements for the fields of astronomy, spectroscopy and communication technologies.
A new method for the study of antiparallel ferroelectric domains
1992
Abstract Beam-coupling topography is a non-destructive holographic technique for spatially resolved recording of hysteresis loops and for imaging of domains. Its basic principle is interference of rays diffracted from a holographic grating with collinear, transmitted ones. Full domain contrast and noise suppression is achieved by appropriate control of intensity and phase of the interfering beams. The method is applied to antiparallel a-domains in (Sr0.61Ba0.39)Nb2O6:Ce.
Direct surface relief pattering of azo-polymers films via holographic recording
2014
In this work surface relief direct formation during holographic recording in poly (Disperse Red 1 – methacrylate) films was studied. In this material azo-dye Disperse Red 1 is covalently attached to the main polymeric chain making lateral mass transport in the film caused by a presence of light electric field direction modulation very fast and effective. Surface relief grating formation process was induced by 532 nm laser. Read-out was performed by 660 nm diode laser. Diffraction efficiencies kinetics dependence on polarization state of reading and recording beams was studied. Surface relief depth on the films was measured by AFM. Deep surface relief gratings were obtained in Poly (Dispers…
Model Eye Incorporating a Manually Tunable Polymer Lens and Microfluidics Chamber for Simulation of Vitreous Floaters
2016
a model eye incorporating a manually tunable lens and microfluidics chamber for simulation of vitreous floaters has been described. Aberrations correspond to average values in population and diffraction effects could be observed.
Pressure dependence in the methyl vinyl ketone + OH and methacrolein + OH oxidation reactions: an electronic structure study.
2005
High-level electronic structure calculations were carried out for the study of the reaction pathways in the OH-initiated oxidations of methyl vinyl ketone (MVK) and methacrolein (MACR). For the two conformers of MVK (called synperiplanar and antiperiplanar), the addition channels of OH to the terminal and central carbon atom of the double bond dominate the overall rate constant, whereas the abstraction of the methyl hydrogen atoms has no significant kinetic role. In the case of MACR, only the antiperiplanar conformer is important in its reactivity. In addition, the lower Gibbs free energy barrier for MACR corresponds to the aldehydic hydrogen abstraction reaction, which will be somewhat mor…
Aromatic Ketones as Photocatalysts: Combined Action as Triplet Photosensitiser and Ground State Electron Acceptor
2006
Positive and negative electrospray ionization-collision-induced dissociation of sulfur- containing zwitterionic liquids.
2011
The mass spectrometric properties of several (1,2-dimethyl-1 H-imidazol-3-ium-3-yl)-alkane-1-sulfonates (alkane=ethyl, propyl and butyl) are investigated in this study. These substances, named zwitterionic liquids (ZILs), were synthesized using classical transformations and analyzed in positive and negative electrospray ionization mode using collision-induced dissociation (0–50 eV). We have also performed regioselective deuterium labeling of the alkyl chain of 3-(1,2-dimethyl-1 H-imidazol-3-ium-3-yl)-propane-1-sulfonates. Thus, the mass spectra of isotopically-labeled compounds were used for the confirmation of fragmentation pathways of ZILs. Briefly, the data obtained in this study show t…
Multilayers of CdSe/CdS/ZnCdS Core/Wings/Shell Nanoplatelets Integrated in a Polymer Waveguide
2017
In this work, fabrication of multilayers of colloidal CdSe/CdS/ZnCdS core/wings/shell nanoplatelets (NPls) on solid substrates by layer-by-layer deposition technology is successfully demonstrated for the first time. Integration of multilayers of nanoplatelets into polymeric waveguide resulted in strong dichroism in absorption and polarization effects in photoluminescence with preferable absorption and emission of TE (horizontal) mode that evidences about in-plane orientation of NPls relative to the planar waveguide. The propagation of the excitation and emission light along the waveguide was thoroughly investigated both theoretically and experimentally for different number of NPl layers.
Properties and interactions – melting point of tribromobenzene isomers
2021
The melting points of tribromobenzene isomers are correlated with the number, nature and distribution of intermolecular interactions in their structures.