Search results for "Crista"
showing 10 items of 180 documents
"Je m’appelle Herschel Grynszpan", Neuilly-lès-Dijon, Editions du Murmure, 2017, 100 p.
2017
National audience; Aujourd'hui, rares ceux qui connaissent le nom d'Herschel Grynszpan. Pourtant, ce jeune juif polonais réfugié en France, fut l'auteur, le 7 novembre 1938 , d'un attentat contre l'ambassade du Troisième Reich à Paris qui servit de prétexte à la nuit de Cristal. Après un procès avorté et le déclenchement de la Seconde Guerre mondiale, Herschel Grynszpan vécut la débâcle sur les routes de province, comme des millions de Français, avant de faire l'objet d'une traque menée par les nazis dans la France défaite de l'été 1940 : ils voyaient en lui la personnification du "complot juif international".
Drawing the Line at Neglected Marine Ecosystems: Ecology of Vermetid Reefs in a Changing Ocean
2016
Vermetid mollusks form reefs that protect coasts from erosion, regulate sediment transport, serve as carbon sinks, and provide habitat for many fish and invertebrates. This biogenic habitat is found in tropical, sub-tropical, and warmtemperate coastal areas, such as Bermuda, oceanic islands in Brazil, and Hawaii, several locations within the Caribbean and the Mediterranean. These reefs are functionally similar to tropical coral fringing reefs but are built by gregarious vermetid gastropods cemented by a crustose coralline algal species, which probably triggers their settlement. Some descriptive studies in different regions worldwide and comparisons among tropical and Mediterranean reefs con…
Unmanned aerial vehicle technology to assess the state of threatened biogenic formations: The vermetid reefs of mediterranean intertidal rocky coasts
2021
Abstract Vermetid bioconstructions are biogenic formations, built by sessile gastropod molluscs belonging to the family Vermetidae worldwide distributed, occurring in the intertidal and upper subtidal in the rocky shores. In the Mediterranean basin, they occur in complex and tridimensional structures that enhance the local biodiversity, allowing to qualify the structuring species as ecosystem engineers. Due to their ecological relevance and considerable extension along the coasts, we assessed their structural complexity using unmanned aerial vehicle (UAV) technology, as tool of littoral cartography analysis of these bioconstructions, and plaster hemispheres dissolution as a descriptor index…
Il concetto di "no-flow temperature" e il problema della solidificazione in flusso durante lo stadio di riempimento nel processo di stampaggio ad ini…
2012
Durante la fase di riempimento del processo di stampaggio ad iniezione, il flusso del materiale polimerico può fermarsi a causa della sua elevata viscosità, nonostante non sia avvenuta la solidificazione tramite transizione vetrosa o cristallizzazione. La no-flow temperature (NFT) è un parametro che rappresenta la "temperatura di solidificazione reologica" di un polimero, ed è utilizzata in molti software di simulazione del processo di stampaggio ad iniezione. L'estrapolazione della viscosità a basse temperature tramite modelli reologici può introdurre errori considerevoli nelle simulazioni, poichè le misure di viscosità sono usualmente effettuate ad alte temperature: in tal modo, i modelli…
Un orafo lombardo a Palermo: Marzio Cazzola
2012
Si ricostruisce la figura di Marzio Cazzola con nuove acquisizioni documentarie e di opere
Reinvestigation of the Pd-catalysed bis(silylation) of alkynes with 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane: Unexpected formation of th…
2013
International audience; The bis(silylated) alkenes Z-(PhSCH2)Me2SiC(H)=C(Fc)SiMe2(CH2SPh) (2) and Z-(PhSCH2)Me2SiC(H)=C(bipheny)SiMe2(CH2SPh) (3) have been prepared by Pd-catalysed double silylation of ethynylferrocene and 4-ethynyl-1,1'-biphenyl in the presence of 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane (1). A reinvestigation on the interaction of 1 with [PdCl2(PhCN)2] in technical-grade CH2Cl2 as solvent revealed competition between reduction to elemental palladium (due to oxidative addition of the Si-Si bond across Pd(II) and subsequent reductive elimination) and formation of an unusual eight-membered chelate complex cis-[PdCl2{(PhSCH2SiMe2)2O}] (4), which is fluxional in s…
The Role of Eucalyptus Species on the Structural and Thermal Performance of Cellulose Nanocrystals (CNCs) Isolated by Acid Hydrolysis
2022
Cellulose nanocrystals (CNCs) are attractive materials due to their renewable nature, high surface-to-volume ratio, crystallinity, biodegradability, anisotropic performance, or available hydroxyl groups. However, their source and obtaining pathway determine their subsequent performance. This work evaluates cellulose nanocrystals (CNCs) obtained from four different eucalyptus species by acid hydrolysis, i.e., E. benthamii, E. globulus, E. smithii, and the hybrid En × Eg. During preparation, CNCs incorporated sulphate groups to their structures, which highlighted dissimilar reactivities, as given by the calculated sulphate index (0.21, 0.97, 0.73 and 0.85, respectively). Although the impact o…
Numerical analysis of thermally induced optical nonlinearity in GaSe layered crystal
1996
A numerical approach to studying thermally induced optical nonlinearity in semiconductors is presented. A transient finite difference algorithm is applied to solve the thermal diffusion equation coupled with the nonlinear absorbance-transmittance of Au/GaSe/Au samples with an applied electric field. The presented analysis can deal with any arbitrary axisymmetric dependence of the input power over the sample and external electric field, and provides information about the steady state and transitory effects in the transmittance.
Preferential azido bridging regulating the structural aspects in cobalt(III) and copper(II)–Schiff base complexes: Syntheses, magnetostructural corre…
2011
International audience; A tridentate NNO donor Schiff base ligand [(1Z,3E)-3-((pyridin-2-yl)methylimino)-1-phenylbut-1-en-1-ol = LH] in presence of azide ions coordinates with cobalt(II) and copper(II) ions giving rise to three new coordination complexes [Co2(L)2(μ1,1-N3)2(N3)2] (1), [Cu2(L)2(μ1,3-N3)]·ClO4 (2) and [(μ1,1-N3)2Cu5(μ-OL)2(μ1,1-N3)4(μ1,1,1-N3)2]n (3). The complexes have been characterized by elemental analysis, FT-IR, UV–Vis spectral studies, and single crystal X-ray diffraction studies. These complexes demonstrate that under different synthetic conditions the azide ions and the Schiff base ligand (LH) show different coordination modes with cobalt(II) and copper(II) ions, givi…
Synthesis of new half sandwich tetrachloro derivatives of molybdenum(V) and tungsten(V). X-ray structures of (C5HPri4)W(CO)3(CH3) and (C5Et5)WCl4
2002
International audience; The new synthetic intermediates (Ring)MCl4 [Ring=C5HPri4 or 4Cp, M=Mo, 2; Ring=C5Et5 or VCp, M=W, 4, Ring=4Cp, M=W, 6] containing sterically protecting cyclopentadienyl ligands have been synthesized. Along the synthetic pathway to 2, it was found that the treatment of [4CpMo(CO)3]− with an aqueous ferric solution according to the well established Manning procedure affords the hydride compound 4CpMo(CO)3H (1) by hydrolysis rather than the expected neutral dimer by oxidation. Compound 1 could be converted, however, to 2 upon oxidation with PhICl2 in good yields. Compound 4 is shown by a single crystal X-ray analysis to adopt a monomeric four-legged piano stool structur…