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showing 10 items of 2851 documents
Structure and dielectric breakdown strength of nano calcium carbonate/polypropylene composites
2013
Nanodielectrics, a 21st-century phenomena, is envisioned to be the answer for material challenges in progressive high-voltage technology. It is well known that the proper dispersion of nanoparticles plays a key role in improving the dielectric properties of a material, but to understand where changes in the properties of a material originate, it is also essential to reveal the multiscale structure of the material. In this study, the dielectric permittivity, breakdown strength, and structure of nano calcium carbonate (nano-CaCO3)/polypropylene composites with 1.8-8.1 wt % doping were characterized systematically. The combined results from transmission electron microscopy, Raman microscopy, a…
BODIPY atropisomer interconversion, face discrimination, and superstructure appending
2016
International audience; A strategy was developed to append sterically hindered apical pickets on both faces of the BODIPY platform to prevent stacking and aggregation. Ortho-substitution of both the meso-phenyl ring and the boron-bound catechol affords the right directionality to append pickets, achieve face discrimination, featuring two inter-convertible atropisomers, and is reminiscent of the picket-fence strategy in porphyrins.
Spectroscopic characterization of alkaline earth uranyl carbonates
2005
A series of alkaline uranyl carbonates, M[UO{sub 2}(CO{sub 3}){sub 3}].nH{sub 2}O (M=Mg{sub 2}, Ca{sub 2}, Sr{sub 2}, Ba{sub 2}, Na{sub 2}Ca, and CaMg) was synthesized and characterized by inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS) after nitric acid digestion, X-ray powder diffraction (XRD), and thermal analysis (TGA/DTA). The molecular structure of these compounds was characterized by extended X-ray absorption fine-structure (EXAFS) spectroscopy and X-ray photoelectron spectroscopy (XPS). Crystalline Ba{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}].6H{sub 2}O was obtained for the first time. The EXAFS analysis showed that this compound consists of …
Photocatalytic activity in gas–solid regime of ZnO-ZnAl2O4 composites
2011
Multi-functional Stabilizers-functionalized Carbon Nanotubes for advanced Ultra-High Molecular Weight Polyethylene-based Nanocomposites
2015
Stabilizing molecules, such as hindered phenols (both synthetic and naturally occurring), polyphenols and hindered amine light stabilizers, were covalently linked or physically absorbed onto outer surface of multi-walled carbon nanotubes (CNTs) and the obtained multi-functional fillers (Stab-f-CNTs) were dispersed in Ultra High Molecular Weight Polyethylene (UHMWPE) aiming at obtaining advanced nanocomposites with enhanced thermo- and/or photo-oxidative stability, electrical and mechanical properties. The chemical grafting or physical absorption of stabilizing molecules is confirmed by spectroscopic, spectrometric and thermo-gravimetric analyses, and the influence of the multi-functional na…
Compared Binding Properties between Resveratrol and Other Polyphenols to Plasmatic Albumin: Consequences for the Health Protecting Effect of Dietary …
2014
International audience; Phytophenols are considered to have beneficial effects towards human physiology. They are food microcomponents with potent chemopreventive properties towards the most three frequent contemporary human diseases, e.g., cardiovascular alterations, cancer and neurodegenerative pathologies. Related to this, the plasmatic form and plasmatic level of plant polyphenols in the body circulation are crucial for their efficiency. Thus, determinations of the binding process of resveratrol and of common flavonoids produced by major edible plants, berries and fruits to plasma proteins are essential. The interactions between resveratrol and albumin, a major plasma protein, were comp…
Design, synthesis and structure-activity relationship of 2-(3',4',5'-trimethoxybenzoyl)-benzo[b]furan derivatives as a novel class of inhibitors of t…
2009
The biological importance of microtubules in mitosis and cell division makes them an interesting target for the development of anticancer agents. Small molecules such as benzo[b]furans are attractive as inhibitors of tubulin polymerization. Thus, a new class of inhibitors of tubulin polymerization based on the 2-(3′,4′,5′-trimethoxybenzoyl)-benzo[b]furan molecular skeleton, with electron-donating (Me, OMe or OH) or electron-withdrawing (F, Cl and Br) substituents on the benzene ring, was synthesized and evaluated for antiproliferative activity, inhibition of tubulin polymerization and cell cycle effects. Adding a methyl group at the C-3 position resulted in increased activity. The most prom…
il volto della morte: le maschere funerarie della sepoltura dei preti morti di Gangi
2014
riassunto — Le mummie moderne e il signifcato recondito della doppia sepoltura nelle culture mediterranee moderne sono da tempo ampiamente dibattuti. In questo lavoro si discute di una particolare “collezione” di corpi di ecclesiastici, mummifcati ed esposti in un comune montano madonita della Sicilia, Gangi. I corpi, principalmente risalenti al XIX secolo, mummifcati per colatura come nella tradizione del tempo e vestiti degli abiti talari, sono esposti nel piano sottostante della Chiesa Madre, in quella che nella tradizione è detta la “fossa dei parrini” (fossa dei preti). Le mummie, a differenza di altri siti siciliani e mediterranei, sono altresì corredate di sonetto commemorativo e di …
Considering lithium-ion battery 3D-printing via thermoplastic material extrusion and polymer powder bed fusion
2021
In this paper, the ability to 3D print lithium-ion batteries through thermoplastic material extrusion and polymer powder bed fusion is considered. Focused on the formulation of positive electrodes composed of polypropylene, LiFePO4 as active material, and conductive additives, advantages and drawbacks of both additive manufacturing technologies, are thoroughly discussed from the electrochemical, electrical, morphological and mechanical perspectives. Based on these preliminary results, strategies to further optimize the electrochemical performances are proposed. Through a comprehensive modeling study, the enhanced electrochemical suitability at high current densities of various complex three…