Search results for " generation"

<title>Nonlinear optical properties of some indandione-1,3 pyridinium betaine derivatives</title>

1997

In this paper nonlinear optical properties of indandione-1,3 pyridinium betaine (IPB) molecule and its novel amphiphilic derivatives have been studied. Hyper-Rayleigh scattering (HRS) has been used as a direct and accurate tool to determine effective hyperpolarizability (beta) of IPB derivatives dissolved in chloroform. Evaluation of hyperpolarizability gives an averaged values of (beta) from 140 multiplied by 10-30 to 450 multiplied by 10-30 esu. Disordering of molecular orientation for multilayer Langmuir-Blodgett films of compound C17-IPB has been studied by SHG techniques and discussed for different film thickness. It has been observed that orientation degree of the Z-type molecular str…

An improved molecular design of obtaining NLO active molecular glasses using triphenyl moieties as amorphous phase formation enhancers

2012

New molecular design of obtaining molecular glasses has been developed by linking triphenylmethyl moieties to chromophore core by flexible C-C bridge. Compounds capable of forming stable amorphous phase with good optical quality have been acquired with increased chemical and thermal sustainability compared to the previously reported design. NLO activity of compounds has been measured after corona discharge polling. Compared to previously synthesized trityloxy fragment containing compounds increase of d 33 coefficient by up to 17 times was achieved for the same chromophore core containing compounds.

Random quasi-phase-matched second harmonic generation in periodically poled lithium tantalate

2009

We experimentally observed and explained bulk second harmonic generation via random quasi-phase-matching, derived from a periodically poled lithium tantalate sample with a randomly patterned mark-to-space-ratio.

ChemInform Abstract: Amphiphilic Dyes for Nonlinear Optics: Dependence of Second Harmonic Generation on Functional Group Substitution.

2010

Covalently linked multi-calixarenes

1998

Abstract ipso-Nitration of t-butyl calix[4]arene tetraethers and subsequent hydrogenation provides an easy access to monoamino calix[4]arenes. Reaction with di- and triacid chlorides leads to various double- and triple-calix[4]arenes. With tetraacid chlorides derived from calix[4]arenes in the cone- or 1,3-alternate-conformations penta-calix[4]arenes are available as molecularly uniform species, which may be regarded as the first generation of calix[4]arene based dendrimers. The structure of the mononitro tetraester derivative, which may serve as a general building block has been confirmed by single crystal X-ray analysis.

Synthetic Inertia Impact on Inter-Area Oscillations of the Continental Europe Power System

2020

The overall kinetic energy reduction due to increasing share of converter-interfaced generation (CIG) has been investigated so far by several works for systems of different types and sizes. The so called synthetic inertia is one of the most common and reviewed solutions to the issue of system inertia reduction. The paper investigates the effects of synthetic inertia as frequency service provided by the CIG sources for the Continental Europe (CE) synchronous area using a detailed large scale dynamic model. The model - provided in the basic form by the System Protection & Dynamics (SP&D) group of the ENTSOE - is properly developed substituting a determined amount of synchronous machin…

Encryption and Generation of Images for Privacy-Preserving Machine Learning in Smart Manufacturing

2023

Current advances in machine (deep) learning and the exponential growth of data collected by and shared between smart manufacturing processes give a unique opportunity to get extra value from that data. The use of public machine learning services actualizes the issue of data privacy. Ordinary encryption protects the data but could make it useless for the machine learning objectives. Therefore, “privacy of data vs. value from data” is the major dilemma within the privacy preserving machine learning activity. Special encryption techniques or synthetic data generation are being in focus to address the issue. In this paper, we discuss a complex hybrid protection algorithm, which assumes sequenti…

Non-linear optical, electrochemical and spectroelectrochemical properties of amphiphilic inner salt porphyrinic systems

2016

Three zwitterionic meso-substituted A3B- and AB2C-porphyrins containing one sulfonato alkylpyridinium substituent and three or two alkoxy-substituted phenyl groups were synthesized in good yield and fully characterized as to their physicochemical properties by a variety of techniques. This new series of inner salt donor-acceptor meso-substituted porphyrin derivatives were prepared for possible application as amphiphilic probes for membrane insertion in the area of combined second-harmonic and two-photon fluorescence cellular microscopy. To this end, the linear and nonlinear optical properties of the compounds were characterized, together with their electrochemical and spectroelectrochemica…

Reconfigurable nonlinear response of dielectric and semiconductor metasurfaces

2021

Abstract Optically resonant dielectric and semiconductor metasurfaces are an emerging and promising area of nanophotonics and light–matter interaction at the nanoscale. Recently, active tuning of the linear response and nonlinear effects of these components has received an increasing amount of interest. However, so far these research directions have remained separated with only few sporadic works that study their combination beginning to appear in the literature. The evolution of nonlinear metasurfaces based on dielectric and semiconductor materials toward reconfigurable and dynamic components could potentially answer the demand of integrated on-chip components that realize essential functi…

An overview of a novel LC resonant device able to improve Power Quality in active and passive distribution networks

2004

Nowadays power distribution systems are under a rapid evolution. The widespread penetration of distributed generation is bringing about new operating conflicts, which are adding to traditional power quality issues. The paper aims to analyse the performance of a new LC device able to improve power quality in electrical distribution systems, even in presence of distributed generation units. The different possible applications of the device are shown and the performances are proved by means of computer simulation. The first experimental results are also presented.