46 Result(s)
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Article
Comparison of Vanillin and Isovanillin Photolysis in Aqueous Solutions
General kinetic regularities of reactions of stationary and laser photolysis of 3-methoxy-4-hydroxybenzaldehyde (vanillin) and 3-hydroxy-4-methoxybenzaldehyde (isovanillin) are investigated by the method of na...
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Article
Optimal Do** of GaSe Crystals for Nonlinear Optics Applications
Centimeter-sized crystals of GaSe have been grown by a modified vertical Bridgman method from a melt with content 0.01, 0.05, 0.1, 0.2, 0.5, 1, and 2 at.% Al and 0.025, 0.1, 0.5, 1, and 2 at.% Er using heat fi...
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Article
Two-Photon Absorption of the DCM Molecule under Femtosecond Excitation between 720 and 920 nm
Nonlinear absorption of the DCM dye has been investigated by the two-quantum etalon method and the z-scan method with excitation by a tunable femtosecond Ti-sapphire laser (3 W, 140 fs, and 80 MHz). The two-ph...
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Article
Structure and properties of nanoparticles fabricated by laser ablation of Zn metal targets in water and ethanol
Size characteristics, structure, and spectral and luminescent properties of nanoparticles fabricated by laser ablation of zinc metal targets in water and ethanol are experimentally investigated upon excitation...
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Article
Silver-nanoparticle based bactericidal coating for poly(glycolide-co-lactide) suture threads obtained by the method of laser ablation of bulk targets in alcohol solutions
A laser ablation method is suggested to synthesize a dispersion of silver nanoparticles to create a bactericidal coating of biodegradable suture material from poly(glycolide-co-lactide) using a bulk target imm...
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Article
Stability and spectral-luminescence properties of CdS and ZnS nanoparticle dispersions, synthesized in various solvents
Stable colloidal solutions of CdS and ZnS nanoparticles of diameter 3–6 nm in ethyl acetate (EA), 2-hydroxy ethyl methacrylate (HEMA), and H2O have been obtained. The size of the synthesized nanoparticles did not...
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Article
Luminescent solar concentrators. I. Concentrators based on mixtures of dyes in PMMA. Spectral and luminescent properties, reabsorption and energy transfer
Spectral and luminescent properties of efficient and stable commercial organic dyes in solutions and polymethylmetacrilate (PMMA), absorbing and emitting in wavelength ranges 300–680 nm and 390–750 nm, respect...
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Article
Investigation of the toxicity of aqueous media after high-energy exposure by the spectralluminescent methods
The spectral and luminescent characteristics of aqueous solutions in the presence of phenol and natural organic acids are investigated after high-energy exposure (to a diffuse barrier discharge or an electron ...
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Article
Optical properties of CdS/MMA dispersions and CdS/PMMA nanocomposites prepared by one-step, size-controlled synthesis
Results of investigations into the optical properties of semiconductor quantum dots (including absorption, fluorescence, and nonlinear scattering) in CdS/MMA dispersions and CdS/PMMA composites prepared by one...
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Article
Limiting the intensity of femtosecond pulses with anti-stokes excitation of organic dye solutions
Results of experimental investigations into the nonlinear absorption of the symmetric polymethine 1-butyl -3,3-dimethyl-2-[5-(1-butyl-3,3-dimethyl-3H-benz[e]indoline-2-uledene)-1,3-pentadienyl]-3H-benz[e]indol...
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Article
A double-frequency solid-state laser on organic compounds
A double-frequency narrow-band tunable laser with a solid-state organic active medium pumped by the 2nd harmonic of a YAG–Nd3+ laser has been developed. The laser emits in the range from uv (with frequency doubli...
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Article
Effect of excited state absorption on the transmissivity of organic-dye-based media under two-photon excitation
duration ranging from femtoseconds to nanoseconds has been simulated. The effect of the absorption from excited singlet and triplet states on the transmissivity of the medium under two-photon excitation has be...
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Article
Parametrical conversion of the frequency of organic lasers into the middle-IR range of the spectrum
The possibility of parametrical conversion of visible radiation of solid-state organic lasers into the middle-IR range of the spectrum in nonlinear GaSe1–x S x ...
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Article
Spectral and luminescent properties of sensitizers based on psoralen substitutes
Psoralens (furocoumarines) are photosensitizers of vegetative origin increasing the sensitivity of biological objects to near-ultraviolet radiation (UV-A, 320–400 nm). In the present work, the influence of sub...
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Article
Anti-stokes fluorescence of polymethine dyes excited by a titanium-sapphire laser
Fluorescence of symmetric polymethine dye solutions (λ abs max ≈ 700 nm) upon anti-Stokes excitation by cw radiation of a titanium-sapphire laser (781 nm) is first i...
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Article
Technique of synthesis and optical properties of CdS/polymethylmethacrylate nanocomposites
The technique of synthesis of polymethylmethacrylate — cadmium sulfide nanocomposites involving precipitation of CdS nanoparticles from polymethylmethacrylate solution in methylmethacrylate monomer with its subse...
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Article
Two-photon—induced fluorescence and electronic structure of substituted dicyanomethylene pyrans in solutions under femtosecond excitation
The method of two-quantum etalon is used to determine the two-photon absorption cross sections of eight dicyanomethylene (DCM) pyran dyes (DCM derivatives). Measurements of two-photon absorption of femtosecond Ti...
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Article
Spectral, luminescent, and lasing properties of pyran derivatives in thin acrylic films under optical excitation
Absorption and fluorescence spectra and lasing ability of pyran derivatives in thin polymeric layers (0.5–0.8 μm) based on polymethylmethacrylate and copolymerized methylmethacrylate and methacrylic acid are i...
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Article
Transient Absorption of Organic Molecules under High-Power Laser Excitation
In the present work, results of investigations into the transient absorption of some organic compounds by the method of pulsed flash photolysis are given. Experimental investigations were carried out using an ...
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Article
Investigation of Spectral-Luminescent and Lasing Properties of Bifluorophoric Molecules. I. Bifluorophores of Linear Structure
Eight bifluorophoric (BF) molecules on the basis of paratherphenyl, stilbene, phenyl, biphenyl (donors) and coumarin 120 and phenylphtalimide (acceptors) connected by the bridging -CH2- were experimentally studie...
