Search results for "Complex"

Visual Methodologies and Geography's education in the pandemic time: notes on geopolitics of migration in the "Mediterranean Complex"

2022

<abstract> <p>The relationship between Geography and the Visual has always been strong intertwined. As it is true that Geography has always operates through images (in the form of pictures, creative representations and above all cartographies), in the last two years, with the distance learning due to the spread of the Covid-19 pandemic, this phenomenon has not only increased, but it also became necessary. "The classroom as the most radical space", in the words of bell hooks, had to turn into a virtual space, where images have a fundamental role in the teaching/learning process. This paper wants to analyse the relationship between Geography and the Visual by analysing three image…

Oscillatory periodic pattern dynamics in hyperbolic reaction-advection-diffusion models

2022

In this work we consider a quite general class of two-species hyperbolic reaction-advection-diffusion system with the main aim of elucidating the role played by inertial effects in the dynamics of oscillatory periodic patterns. To this aim, first, we use linear stability analysis techniques to deduce the conditions under which wave (or oscillatory Turing) instability takes place. Then, we apply multiple-scale weakly nonlinear analysis to determine the equation which rules the spatiotemporal evolution of pattern amplitude close to criticality. This investigation leads to a cubic complex Ginzburg-Landau (CCGL) equation which, owing to the functional dependence of the coefficients here involve…

Sparsity-aware multiple relay selection in large multi-hop decode-and-forward relay networks

2016

In this paper, we propose and investigate two novel techniques to perform multiple relay selection in large multi-hop decode-and-forward relay networks. The two proposed techniques exploit sparse signal recovery theory to select multiple relays using the orthogonal matching pursuit algorithm and outperform state-of-the-art techniques in terms of outage probability and computation complexity. To reduce the amount of collected channel state information (CSI), we propose a limited-feedback scheme where only a limited number of relays feedback their CSI. Furthermore, a detailed performance-complexity tradeoff investigation is conducted for the different studied techniques and verified by Monte …

Cadmium Metal–Organic Frameworks Based on Ditopic Triazamacrocyclic Linkers: Unusual Structural Features and Selective CO 2 Capture

2017

International audience; Two three-dimensional cadmium metal organic frameworks with general formula [Cd-2(L-1)(H2O)(3)](NO3)(0.7)(HCOO)(0.2)Br-0.1 (Cd2L1, L-1 = 1,4,7-tris(4-carboxybenzy1)-1,4,7-triazacyclononane) and Cd(HL2)(H2O)(2) (CdL2, L-2 = 1,4,7-tris(3-(4-benzoate)prop-2-yn-1-yl)-1,4,7-triazacydononane) based on 1,4,7-triazacyclononane N-functionalized by different arylcarboxylic acids were prepared under solvothermal conditions and characterized by single crystal X-ray analysis and porosity measurements. The crystal structure of Cd2L1 reveals a cationic net with a bcs topology,. and nodes are constituted by dinuclear cadmium complexes, in which each cadmium atom adopts a hexacoordin…

The complex formation equilibria between Zn(II) and iminodiacetic acid (IDA) in NaClO4 1 M at 25°C

2009

Etude théorique de surfaces d'énergie potentielle, de moment dipolaire et de polarizabilité des complexes de van der Waals CH4-N2 et C2H4-C2H4

2010

In the present thesis both ab initio and analytical calculations were carried out for thepotential energy, dipole moment and polarizability surfaces of the weakly bound van der Waals complexes CH4-N2 and C2H4-C2H4 for a broad range of intermolecular separations and configurations in the approximation of the rigid interacting molecules. For ab initio calculations the CCSD(T), CCSD(T)-F12 and less computationally expensive methods such as MP2, MP2-F12, SAPT, DFT-SAPT were employed (for all methods the aug-cc-pVTZ basis set was used). The BSSE correction was taken into account during the calculations. The analytical calculations were performed in the framework of the classical long-range appro…

α-Conotoxins EpI and AuIB switch subtype selectivity and activity in native versus recombinant nicotinic acetylcholine receptors

2003

The Xenopus laevis oocyte expression system was used to determine the activities of alpha-conotoxins EpI and the ribbon isomer of AuIB, on defined nicotinic acetylcholine receptors (nAChRs). In contrast to previous findings on intracardiac ganglion neurones, alpha-EpI showed no significant activity on oocyte-expressed alpha3beta4 and alpha3beta2 nAChRs but blocked the alpha7 nAChR with an IC50 value of 30 nM. A similar IC50 value (103 nM) was obtained on the alpha7/5HT3 chimeric receptor stably expressed in mammalian cells. Ribbon AuIB maintained its selectivity on oocyte-expressed alpha3beta4 receptors but unlike in native cells, where it was 10-fold more potent than native alpha-AuIB, had…

Ground and first excited electronic state interaction of FAD with some β-carboline derivatives

1987

Abstract The spectrophotometric and thermodynamic properties of molecular complexes of flavine adenine dinucleotide (FAD) with some dihydro β-carboline derivatives have been investigated in aqueous solution. The molecular associations have been examined by means of electronic absorption spectra, since in each a new charge-transfer band has been located, and also the variation of the fluorescence emission of FAD on the solutions has been observed. The formation constants for the molecular complexes were determined from absorption data, using the Foster-Hammick-Wardley method. The quenching fluorescence phenomena observed in FAD is related to the concentration of the dihydro β-carboline deriv…

The Commented Walk Method as a Way of Highlighting Precise Daily Mobility Difficulties – A Case Study Focusing on Cognitive or Mental Diseases

2016

Abstract The French Act of 11 February 2005 on equal rights and opportunities, participation and citizenship of people with disabilities highlights the need “for people with disabilities or reduced mobility” to have access to the complete mobility chain of the transport system. This law was initially planned to apply from 2015. Many efforts have been made to improve life for those with physical, visual and, to a lesser extent, hearing impairments. But there is a lot of room for improvement in situations regarding psychological, cognitive and mental impairment. This is largely due to a lack of knowledge on the difficulties experienced by the above when they travel. The national quantitative …