49 research outputs found
Voix d'outre-temps : Chikhates Brika et Zineb. Une effraction archivistique
No full textThis text explores the powerful rediscovery of the forgotten voices of Moroccan popular singers Chikha Brika and Chikha Zineb, pivotal yet marginalized figures in the tradition of ʿAyta music. Through a passage by Eugène Aubin and the archival recordings available on Gallica (BnF), the author examines the emotional charge and affective knowledge triggered by sonic archives. Far from any romanticization or exotic gaze, the text highlights how these rural female voices—once silenced—resurface with force through the grooves of old vinyl records. This "archival breach" becomes an intimate and political experience, in which listening restores dignity and presence to what history tried to erase. The text reflects on the spectral nature of recorded voices and rethinks the researcher’s role as a host of haunted memory and affective knowledge.Ce texte explore la redécouverte bouleversante des voix oubliées des chanteuses marocaines populaires Chikha Brika et Chikha Zineb, figures majeures mais marginalisées du chant de l’ʿAyta. À partir d’un passage d’Eugène Aubin et d’écoutes archivistiques via Gallica (BnF), l’auteur interroge la matérialité sonore de l’archive et ses effets émotionnels. Loin de tout exotisme ou fétichisation, il décrit l’irruption de ces voix féminines rurales, à la fois effacées des récits dominants et intensément présentes dans le sillon du vinyle. Cette « effraction archivistique » devient une expérience sensible, politique et éthique, où l’écoute fait émerger une connaissance affective et une reconnaissance réparatrice. Le texte s'inscrit dans une réflexion sur les formes de présence de l’archive sonore, la spectralité des voix et le rôle du chercheur comme hôte d’une mémoire occultée
Conundrum in Measured Electron Affinities of Complex Heavy Atoms
No full textLow-energy electron scattering from the lanthanide atoms Eu, Tb, Tm, Gd, and Nd including Nb is investigated through calculated electron elastic total cross sections using our robust Regge-pole methodology. The extracted binding energies of the resultant ground and metastable anions formed during the collisions are contrasted with the measured electron affinities (EAs). It is concluded that the measured EAs for these atoms require reinterpretation and new recommended values are presented
Electron Elastic Collisions with Pu, Am and Lr Actinide Atoms
No full textSynopsis The robust Regge-pole methodology which embeds the crucial electron correlations and the vital core-polarization interaction is used to explore negative-ion formation in the actinide atoms Pu, Am and Lr through the electron elastic total cross sections (TCSs) calculation. The TCSs are found to be characterized by ground, metastable and excited anionic formation, whence we extract the anionic binding energies and compare them with existing electron affinities. The TCSs exhibit both atomic and molecular behavior in addition to polar- ization-induced metastable TCSs
Fullerene Negative Ions: Formation and Catalysis
No full textWe first explore negative-ion formation in fullerenes C44 to C136 through low-energy electron elastic scattering total cross sections calculations using our Regge-pole methodology. Then, the formed negative ions C44?t o C136? are used to investigate the catalysis of water oxidation to peroxide and water synthesis from H2 and O2. The exploited fundamental mechanism underlying negative-ion catalysis involves hydrogen bond strength-weakening/breaking in the transition state. Density Functional Theory transition state calculations found C60? optimal for both water and peroxide synthesis, C100? increases the energy barrier the most, and C136? the most effective catalyst in both water synthesis and oxidation to H2O2
Novel Mechanism for Creating Long-Lived Metastable Atomic Negative Ions
No full textA novel mechanism is proposed for creating long-lived metastable atomic negative ions in complex atoms. It exploits the orbital collapse of the 5d orbital in Gd (Z=64) into the 4f orbital of Tb (Z=65). In the region of collapse the properties of the 5d and 4f orbitals are quite sensitive to the changes in the effective potential. Consequently the collapse phenomenon impacts significantly the core-polarization interaction in the relevant atoms. The mechanism is demonstrated in Tb and Dy through the appearance of long-lived Tb? and Dy? anions in the Regge-pole calculated electron elastic cross sections
Resonances in Low-Energy Electron Elastic Scattering From Fullerenes
No full textThe benchmarked Regge-pole method on the calculated low-energy electron elastic scattering total cross section (TCS) for C60 through the measured electron affinity (EA) [1, 2] is used to calculate TCSs for selected fullerenes, from C54 through C240 in the electron impact energy range 0.02 ? E ? 10.0 eV. From the characteristic dramatically sharp resonances representing long-lived ground state fullerene negative ion formation we extracted the binding energies (BEs) and compared them with the measured EAs, obtaining outstanding agreement
The germinating power of seeds of mango trees
No full textThe author studied the storage of seeds of mango trees with the aim of Keeping high its ability of germination. Seven means of storage were tried, with two temperatures: environment temperature (22 to 27 degrees Centigrade) and cold store room (5 degrees centigrade). The methods of storage tried were: 1 - The frewit kept complete. 2 - Seeds taken within the stone. 3 - Seeds taken out of the stone. 4 - Stones heated with a Fungicida (Zineb). 5 - Stones cut laterally and heated with a fungicide (Zineb). 6 - Seeds (out of sones) heated with Zineb. 7 - Stones steatified with sand. The best results were obtained for seeds kept within whole fruits, probably owing to protection provided by outer layers. The use of fungicide imposed the sanitary aspect of seeds and stones. Storage in cold store room (5 degrees Centigrade) injured the seeds and stones in all cases. Germinating power was kept high up to 70 days for complete fruits. It seems that biggers fruits were more favorable to keep high the ability of theirs seeds to germinate
New Insights in Low-Energy Electron-Fullerene Interactions
No full textRegge pole calculated low-energy electron scattering total cross sections (TCSs) for ground and first excited states of fullerenes are generally robust; for C20 they resemble those of atomic Au. Here we explore the variation of R, the ratio of second to first Ramsauer-Townsend minima of excited states TCSs, from C20 through C70. We find that for C20 R is close to that for Au (> 1.) while for C24 R is about unity. For C70 R is less than 0.5 demonstrating strong departure from atomic behavior due to significant polarization interaction in C70; which also induces long-lived metastable anions in C70
Binding Energies of Fullerene and Complex Atomic Negative Ions
No full textA robust potential which embeds fully the vital core polarization interaction has been used in the Regge-pole method to explore low-energy electron scattering from C60, Eu and Nb through the total cross sections (TCSs) calculation. From the characteristic dramatically sharp resonances in the TCSs manifesting negative ion formation in these systems, we extracted the binding energies (BEs) for the C60 ?, Eu? and Nb? anions. Our BE for C60 ? ground state is in outstanding agreement with the measured electron affinity (EA) of C60 [1]. For anionic Eu? and Nb? our BEs are compared with the measured EAs [2-4]
Research in medical education - chances and challenges : international conference, 20th - 22nd May 2009, Heidelberg ; congress abstracts
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