Third order NLO properties of modified azo-azulenes

In this work there are reported third order nonlinear optical properties of some new azo- functionalized azulene derivatives. They were studied using standard methods - degenerate four waves mixing and third harmonic generation and nonlinear optical absorption. The obtained results allow us to conclude that NLO properties of an azulene molecule can be significantly enhanced by substitution with an electron accepting an acetamidophenyl group

Mild hydration of didecyldimethylammonium chloride modified DNA by 1H-nuclear magnetic resonance and by sorption isotherm

The gaseous phase hydration of deoxyribonucleic acid and didecyldimethylammonium chloride (C19H42ClN) complexes (DNA-DDCA) was observed using hydration kinetics, sorption isotherm, and high power nuclear magnetic resonance. Three bound water fractions were distinguished: (i) a very tightly bound water not removed by incubation over silica gel, (ii) a tightly bound water saturating with the hydration time t(1)(h) (0.596 +/- 0.04) h, and a loosely bound water fraction, (iii) with the hydration time t(2)(h) (20.9 +/- 1.3) h. Proton free induction decay was decomposed into the signal associated with the solid matrix of DNA-DDCA complex (T-2S approximate to 30 mu s) and two liquid signal components coming from tightly bound (T-2L1 approximate to 100 mu s) and from loosely bound water fraction (T-2L2 approximate to 1000 mu s)

Azo-azulene based compounds-nonlinear optical and photorefractive properties

This work reports on nonlinear optical properties of some azo-functionalized azulene derivatives. Linear and nonlinear optical absorption, second- and third harmonic generation were used as diagnostic tools. It was demonstrated that light induced a surface pattern on thin films containing the studied compounds. The results indicate an important role of thiazole substitution for enhancing NLO properties of the azulene derivatives

Influence of surfactant on dynamics of photoinduced motions and light emission of a dye-doped deoxyribonucleic

Pure deoxyribonucleic acid (DNA) is known to be soluble in water only and exhibits poor temperature stability. In contrary, it is well known that the complex of DNA - with cetyltrimethyl ammonium (CTMA) is insoluble in water but soluble in alcohols and can be processed into very good optical quality thin films by solution casting or spin deposition. Despite the success of DNA-CTMA, there is still need for new cationic surfactants which would extend the range of available solvents for DNA complex. We test and present experimental results of influence of new surfactants replacing CTMA in the DNA complex and based on benzalkonium chloride (BA) and didecyldimethylammonium chloride (DDCA) on their optical properties. Particularly, we were interested in all optical switching and light generation in amplified spontaneous emission process in these materials

Thermal stability of blends containing azo-carbazole derivatives and epoxy resin, designed for nonlinear optical applications

Many studies have been intended to synthesize new thermally stable organic materials and polymers for nonlinear optical applications. These materials are most often guest–host systems and present some inconveniences like solvents compatibility for both the matrix and the chromophore. In the present work, we propose to use an epoxy resin as matrix for chromophores. Three blends containing an epoxy resin and azo-carbazole derivatives (either physically dispersed or chemically bound) were studied. They were prepared in form of thin films. We report their nonlinear optical properties investigated by third harmonic generation (THG) by Maker fringes technique, as well as thermal stability of these characteristics. The results show different behaviour for dispersed chromophore in a matrix and covalently bounded chromophore

Photoinduced Gratings in Functionalized Azo-Carbazole Compounds in Picosecond Regime

We report results of diffraction grating inscription on thin films prepared from epoxy resin doped with azo-carbazole based dyes. Diffraction gratings were recorded at the wavelength 532 nm and monitored through intensity of first order of diffraction (632 nm). Atomic force microscope scans of the gratings show that a surface relief grating also appeared

Opportunities of deoxyribonucleic acid complexes composites for nonlinear optical applications

In this paper, we illustrate new functionalities for nonlinear optical applications of bio-molecular systems. This study presents DNA complex with new ionic surfactants. These surfactants enabled DNA solubility in solvents other than alcohols, like aromatic and chlorinated ones. Composites with two nonlinear optical (NLO) active dyes are subjects of the second and third harmonic generation experiments. The found effective nonlinear susceptibilities values are much higher than that for standard fused silica. We also demonstrate any influence of the surfactant on NLO properties. (C) 2011 American Institute of Physics. [doi:10.1063/1.3655985

Theoretical and Experimental Studies of NLO Properties of New Carbazole Derivatives

In this article we report theoretical calculations and experimental findings concerning linear optical and nonlinear optical properties of three model azo-carbazole derivative dyes. The goal of the work was to answer to what extent theoretical modeling can predict actual properties of a series of these dyes. Theoretical calculations were based on MM +, AM1 and PM3 models. Experimental data were obtained through UV-vis spectroscopy and electro-optic method

An operational analysis of Lake Surface Water Temperature

Operational analyses of Lake Surface Water Temperature (LSWT) have many potential uses including improvement of numerical weather prediction (NWP) models on regional scales. In November 2011, LSWT was included in the Met Office Operational Sea Surface Temperature and Ice Analysis (OSTIA) product, for 248 lakes globally. The OSTIA analysis procedure, which has been optimised for oceans, has also been used for the lakes in this first version of the product. Infra-red satellite observations of lakes and in situ measurements are assimilated. The satellite observations are based on retrievals optimised for Sea Surface Temperature (SST) which, although they may introduce inaccuracies into the LSWT data, are currently the only near-real-time information available. The LSWT analysis has a global root mean square difference of 1.31 K and a mean difference of 0.65 K (including a cool skin effect of 0.2 K) compared to independent data from the ESA ARC-Lake project for a 3-month period (June to August 2009). It is demonstrated that the OSTIA LSWT is an improvement over the use of climatology to capture the day-to-day variation in global lake surface temperatures