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991.
992.
It is shown that when q is a primitive root of unity of order not equal to 2 mod 4, A(SLq(2)) is a free module of finite rank over the coordinate ring of the classical group SL(2). An explicit set of generators is provided. 相似文献
993.
Zahra Farmani Alessandro Vetere Corentin Poidevin Alexander A. Auer Wolfgang Schrader 《Angewandte Chemie (International ed. in English)》2020,59(35):15008-15013
Buckyballs (fullerenes) were first reported over 30 years ago, but still little is known regarding their natural occurrence, since they have so far only been found at sites of high‐energy incidents, such as lightning strikes or meteor impacts, but have not been reported in low‐energy materials like fossil fuels. Using ultrahigh‐resolution mass spectrometry, a wide range of fullerenes from C30 to C114 was detected in the asphaltene fraction of a heavy crude oil, together with their building blocks of C10nH10 stoichiometry. High‐level DLPNO‐CCSD(T) calculations corroborate their stability as spherical and hemispherical species. Interestingly, the maximum intensity of the fullerenes was found at C40 instead of the major fullerene C60. Hence, experimental evidence supported by calculations show the existence of not only buckyballs but also buckybowls as 3‐dimensional polyaromatic compounds in fossil materials. 相似文献
994.
Jimena Ospina Alessandro Sorrenti Ona Illa Ramon Pons Rosa M. Ortuño 《Tetrahedron: Asymmetry》2013,24(12):713-718
New enantiopure cyclobutane derivatives have been synthesized from a chiral precursor derived from (?)-verbenone. The cyclobutane moiety acts as a chiral platform to afford a γ-amino acid function in a branched side-chain containing an additional stereogenic centre as well as additional C6 or C16-alkyl chains linked to the ring by means of an amine or an amide function. One of these compounds, obtained as a 1:2 mixture with its TFA salt has been investigated, suggesting behaviour as a good surfactant and its critical micellar concentration has been determined. 相似文献
995.
996.
Theoretical and experimental characterization of amino‐PEG‐phosphonate‐terminated Polyphosphorhydrazone dendrimers: Influence of size and PEG capping on cytotoxicity profiles
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Aurélien Hameau Séverine Fruchon Christian Bijani Alessandro Barducci Muriel Blanzat Rémy Poupot Giovanni M. Pavan Anne‐Marie Caminade Cédric‐Olivier Turrin 《Journal of polymer science. Part A, Polymer chemistry》2015,53(6):761-774
The synthesis of new series of PPH (poly(phosphorhydrazone)) dendrimers with amino‐PEG phosphonates or the corresponding amino‐PEG phosphonic acids as terminal groups is presented, from generations 1–3. The size of PEG‐terminated dendrimers is experimentally measured by diffusional NMR, and by means of dynamic light scattering. Classical molecular dynamics and well‐tempered metadynamics simulations are used to assess or confirm the formation of aggregates in some cases. The influence of PEG capping on the cytotoxicity profiles of the dendrimers is evaluated on human peripheral blood mononuclear cells by means of LIVE/DEAD assays, and confirms the importance of PEG capping to ensure low cytotoxicity. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 761–774 相似文献
997.
998.
Alessandro Brozzi Andrea Capotorti Barbara Vantaggi 《International Journal of Approximate Reasoning》2012,53(8):1124-1136
Several economic applications require to consider different data sources and to integrate the information coming from them. This paper focuses on statistical matching, in particular we deal with incoherences. In fact, when logical constraints among the variables are present incoherencies on the probability evaluations can arise. The aim of this paper is to remove such incoherences by using different methods based on distances minimization or least commitment imprecise probabilities extensions. An illustrative example shows peculiarities of the different correction methods. Finally, limited to pseudo distance minimization, we performed a systematic comparison through a simulation study. 相似文献
999.
Dr. Alessandro Soncini Prof. Patrick W. Fowler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(5):1740-1746
We propose a molecular‐orbital model to explain how majority and minority spins in odd‐π‐electron carbocycles sustain counter‐rotating magnetic‐field‐induced ring currents. The model is based on the ipsocentric approach to magnetic response, in which ring currents are dominated by frontier‐orbital contributions obeying angular‐momentum selection rules. Coupled unrestricted Hartree–Fock ab initio calculations of the ring‐current responses for singly charged benzene and planarised cyclo‐octatetraene ions confirm the predictions of the qualitative model, and are consistent with correlated MP2 spin‐polarised current calculations. 相似文献
1000.