Search results for " Active"

MS-CASPT2 analysis of the UV thermochromism of octamethyltrisilane

2006

We interpret the reversal of the direction of the thermochromic shift of the first absorption band of peralkylated oligosilanes as the silicon chain is extended, based on multistate complete active space second-order perturbation theory (MS-CASPT2) calculations for octamethyltrisilane, Si3Me8. The observed shift is attributed to the effect of b1 distortions from ground state equilibrium geometry on vertical excited state energies and intensities. A generally contracted basis set of atomic natural orbitals (ANOs) at a ground state geometry optimized in the second-order Moller–Plesset perturbation theory (MP2) approximation with Dunning's correlation consistent triple-zeta basis set (cc-pVTZ)…

Meaningful learning in business through serious games

2017

Purpose: The requirements of a business executive include the talent and creativity to solve problems and adapt to continuous changes presented by the economic and social environment. However, the university does not often prepare students in these skills. Businesses simulations are didactic tools in which participants assume a role and make decisions which affect the results of the company. This paper aims to provide empirical evidence on the effectiveness of business simulations in university teaching. Design/methodology: We have implemented business simulations in a course in the College of Economics at the University of Valencia, during the 2015-2016 academic year. Questionnaires were u…

A prospective new diagnostic technique for distinguishing eruptive and noneruptive active regions

2019

This research has received funding from the Science and Technology Facilities Council (UK) through the consolidated grant ST/N000609/1 and the European Research Council (ERC) under the European Union Horizon 2020 research and innovation program (grant agreement No. 647214). This work used the DiRAC@Durham facility managed by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (www.dirac.ac.uk). The equipment was funded by BEIS capital funding via STFC capital grants ST/P002293/1, ST/R002371/1, and ST/S002502/1, Durham University and STFC operations grant ST/R000832/1. DiRAC is part of the National e-Infrastructure. S.L.Y. would like to acknowledge STFC for sup…

Study of the diurnal cycle of stressed vegetation for the improvement of fluorescence remote sensing

2006

Chlorophyll fluorescence (Chf) emission allows estimating the photosynthetic activity of vegetation - a key parameter for the carbon cycle models - in a quite direct way. However, measuring Chf is difficult because it represents a small fraction of the radiance to be measured by the sensor. This paper analyzes the relationship between the solar induced Chf emission and the photosynthetically active radiation (PAR) in plants under water stress condition. The solar induced fluorescence emission is measured at leaf level by means of three different methodologies. Firstly, an active modulated light fluorometer gives the relative fluorescence yield. Secondly, a quantitative measurement of the Ch…

Insertion des jeunes : 1986, l'année stage

1986

Statistical distributions for hamiltonian systems coupled to energy reservoirs and applications to molecular energy conversion

2008

We study systems with Hamiltonian dynamics type coupled to reservoirs providing free energy which may be converted into acceleration. In the first part we introduce general concepts, like canonical dissipative systems and find exact solutions of associated Fokker–Planck equations that describe time evolutions of systems at hand. Next we analyze dynamics in ratchets with energy support which might be treated by perturbation theory around canonical dissipative systems. Finally we discuss possible applications of these ratchet systems to model the mechanism of biological energy conversion and molecular motors.

Biological activity studies on organotin(IV)n+ complexes and parent compounds

2006

This review summarized the literature and own data on the parent organotin(IV) compounds and complexes formed with biologically active ligands.

Zur Stereochemie der Oxidation chiraler, tertiärer Phosphine mit Dimethylsulfoxid

1976

Es wird uber den sterischen Verlauf der Oxidation der optisch aktiven, tertiaren Phosphine 3 and 4 mit Dimethylsulfoxid berichtet. Diese Umsetzung verlauft nur in Gegenwart elektrophiler Katalysatoren (Tabelle 1). Je nach Art and Menge des Katalysators zeigt die Stereochemie der Reaktion entweder uberwiegende Inversion oder Retention der Konfiguration am Phosphor an (Tabellen 2, 3); in einigen Fallen wird jedoch fast vollstandige Racemisierung beobachtet (Tabelle3). Auf der Grundlage dieser stereochemischen Resultate werden mogliche Mechanismen fur diese Umsetzung diskutiert. The Sterochemistry of the Oxidation of Chiral Tertiary Phosphines by Means of Dimethyl Sulfoxide The steric course o…

The reaction of optically active α-aminocarboxylic acid hydrazides with triethyl orthoesters

2011

New derivatives of 2-(1-amino-1-phenylmethyl)-1,3,4-oxadiazole and 1,2,4-triazin-6-one were synthesised in the reactions of optically active α-aminocarboxylic acid hydrazides and triethyl orthoesters in xylene. The electronic and steric effects of substituents at the α position influencing the formation of five- or six-membered products are discussed.

Shallow submarine gas manifestations in the Aegean Sea: preliminary catalogue and geochemical characterization

2017

The Aegean area, like other regions of intense geodynamic activity, is characterised by extensive geogenic degassing. Gas manifestations widespread on land are also very frequent underwater. The present study aims at producing a first catalogue of these manifestations together with the geochemical characterization of the emitted gases. Sixty-one samples at 21 different sites have been collected by diving up to 15 m depth, mainly along the south Aegean active volcanic arc (SAAVA). The sites displayed very different gas fluxes. Most of them showed a very sluggish gas bubbling while a few had spatially large and strong bubbling. The most intense manifestation has been found at Kos Island along…