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Kristian Piscicchia Johann Marton Sergio Bartalucci Massimiliano Bazzi Sergio Bertolucci Mario Bragadireanu Michael Cargnelli Alberto Clozza Raffaele Del Grande Luca De Paolis Carlo Fiorini Carlo Guaraldo Mihail Iliescu Matthias Laubenstein Marco Miliucci Edoardo Milotti Fabrizio Napolitano Andreas Pichler Alessandro Scordo Hexi Shi Diana Laura Sirghi Florin Sirghi Laura Sperandio Oton Vazquez Doce Johann Zmeskal Catalina Curceanu 《Entropy (Basel, Switzerland)》2020,22(11)
The VIP collaboration is performing high sensitivity tests of the Pauli Exclusion Principle for electrons in the extremely low cosmic background environment of the underground Gran Sasso National Laboratory INFN (Italy). In particular, the VIP-2 Open Systems experiment was conceived to put strong constraints on those Pauli Exclusion Principle violation models which respect the so-called Messiah–Greenberg superselection rule. The experimental technique consists of introducing a direct current in a copper conductor, and searching for the X-rays emission coming from a forbidden atomic transition from the L shell to the K shell of copper when the K shell is already occupied by two electrons. The analysis of the first three months of collected data (in 2018) is presented. The obtained result represents the best bound on the Pauli Exclusion Principle violation probability which fulfills the Messiah–Greenberg rule. 相似文献
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Alessandro Bagno 《Comptes Rendus Chimie》2012,15(2-3):118-123
The 183W NMR spectra of the lacunary Keggin polyoxotungstate [PW11O39]7– feature noticeable differences according to the counterion (Li or Na). Such differences are modeled by ion pairs where the lacuna is occupied by a Li(H2O)+ or Na(H2O)+ group through relativistic DFT calculation of the tungsten chemical shifts. 相似文献
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One‐pot,solvent‐free,metal‐free synthesis and UCST‐based purification of poly(ethylene oxide)/poly‐ε‐caprolactone block copolymers 下载免费PDF全文
Alessandro Ianiro Isabel Jiménez‐Pardo A. Catarina C. Esteves Remco Tuinier 《Journal of polymer science. Part A, Polymer chemistry》2016,54(18):2992-2999
A fast, one pot, solvent‐free and metal‐free synthesis of poly‐ε‐caprolactone and poly(ethylene oxide) block copolymers is reported. Copolymers with different molar mass, different hydrophilic to lipophilic balance, high degree of conversion and narrow molar mass dispersity have been obtained by organocatalyzed ring opening polymerization of ε‐caprolactone in presence of mono‐ or diol‐poly(ethylene oxide) as initiator and fumaric acid as catalyst. A new biocompatible and environmental friendly purification method is presented, exploiting the upper critical solution temperature of these class of copolymers in ethanol. The phase diagrams of the synthesized copolymers in ethanol are also reported. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2992–2999 相似文献
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Mónica Gomes Alessandro Gandini Armando J. D. Silvestre Bruno Reis 《Journal of polymer science. Part A, Polymer chemistry》2011,49(17):3759-3768
Novel polyesters from renewable resources based on 2,5‐dicarboxylic acid and several diols were synthesized and characterized using different polycondensation techniques. The aliphatic diols were sufficiently volatile to allow the use of polytransesterifications, which gave high‐molecular weight semicrystalline materials with good thermal stability. In particular, the polyester based on ethylene glycol displayed properties comparable with those of its aromatic counterpart, poly(ethylene terephthalate), namely, the most important industrial polyester. The use of isosorbide gave rise to amorphous polymers with very stiff chains and hence a high glass transition temperature and an enhanced thermal stability. The interfacial polycondensation between the acid dichloride and hydroquinone produced a semicrystalline material with features similar to those of entirely aromatic polyesters, characterized essentially by the absence of melting and poor solubility, both associated with their remarkable chain rigidity. The replacement of hydroquinone with the corresponding benzylic diol was sufficient to provide a more tractable polyester. This study provided ample evidence in favor of the exploitation of furan monomers as renewable alternatives to fossil‐based aromatic homologs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献