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81.
N-benzyl-tert-butyl nitroxide derivatives substituted at the aromatic ring form host-guest inclusion complexes with β-and γ-cyclodextrin. They were employed as probes to assess substituent effects on the geometry of the complex and on the kinetics of this complexation by combining EPR and (1)H NMR data. 相似文献
82.
Franchi P Lucarini M Pedulli GF Bandini E 《Chemical communications (Cambridge, England)》2002,(6):560-561
The detection and characterisation in liquid solution by EPR spectroscopy of the rotational conformers of a nitroxide radical containing a chiral centre is reported for the first time. 相似文献
83.
We consider groups Γ of automorphisms of a groupG acting by means of power automorphisms on the factors of a normal series inG with lengthm. We show that [G, Γ] is nilpotent with class at mostm and that this bound is best possible. Moreover, such a Γ is parasoluble with paraheight at most 1/2m(m+3)+1, provided Γ′ is periodic. We give best possible bound in the case where the series is a central one. 相似文献
84.
G. Muoz-Matutano B. Aln J. Martínez-Pastor L. Seravalli P. Frigeri S. Franchi 《Superlattices and Microstructures》2008,43(5-6):494
Photoluminescence and excitation of photoluminescence spectroscopy have been performed for two kinds of single InAs self-assembled quantum dots grown on GaAs. The presence of unintentional impurities (donors and acceptors) offers the possibility to switch from negative to positively charged excitons by selectively exciting impurity related optical transitions. 相似文献
85.
86.
Ottani V Raspanti M Martini D Tretola G Ruggeri A Franchi M Giuliani Piccari G Ruggeri A 《Micron (Oxford, England : 1993)》2002,33(2):121-125
The events at the hydroxyapatite implant material/tissue interface following electromagnetic stimulation were studied in the rabbit. Two kinds of hydroxyapatite were used: natural (NA) and synthetic (HA) both with a grain size of <50 microm. Bone defects, artificially created in rabbit tibiae, were filled with the material examined. One group of animals was exposed immediately after surgery and every 12h thereafter to 30-min treatments with electromagnetic fields (PEMFs). A second group was used as a control (untreated). Two and 4 weeks after implantation, animals were sacrificed and bone samples processed for LM, TEM and SEM using a backscatter electron detector for the evaluation of bone growth. This study indicates that HA has more osteoconductivity than NA, and shows that PEMF-treatment results in a benefit in accelerating bone formation at early time periods. 相似文献
87.
Dr. Paola Franchi Valentina Bleve Prof. Dr. Elisabetta Mezzina Christian Schäfer Giulio Ragazzon Dr. Marco Albertini Prof. Donatella Carbonera Prof. Dr. Alberto Credi Prof. Marilena Di Valentin Prof. Marco Lucarini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(26):8745-8750
Gaining detailed information on the structural rearrangements associated with stimuli‐induced molecular movements is of utmost importance for understanding the operation of molecular machines. Pulsed electron–electron double resonance (PELDOR) was employed to monitor the geometrical changes arising upon chemical switching of a [2]rotaxane that behaves as an acid–base‐controlled molecular shuttle. To this aim, the rotaxane was endowed with stable nitroxide radical units in both the ring and axle components. The combination of PELDOR data and molecular dynamic calculations indicates that in the investigated rotaxane, the ring displacement along the axle, caused by the addition of a base, does not alter significantly the distance between the nitroxide labels, but it is accompanied by a profound change in the geometry adopted by the macrocycle. 相似文献
88.
The purpose of this article is to introduce and study a relativistic motion whose acceleration, in proper time, is given by a white noise. We deal with general relativity and consider more closely the problem of the asymptotic behavior of paths in the Schwarzschild geometry example. © 2006 Wiley Periodicals, Inc. 相似文献
89.
A Carnot group is a connected, simply connected, nilpotent Lie group with stratified Lie algebra. We study the notions of intrinsic graphs and of intrinsic Lipschitz graphs within Carnot groups. Intrinsic Lipschitz graphs are the natural local analogue inside Carnot groups of Lipschitz submanifolds in Euclidean spaces, where “natural” emphasizes that the notion depends only on the structure of the algebra. Intrinsic Lipschitz graphs unify different alternative approaches through Lipschitz parameterizations or level sets. We provide both geometric and analytic characterizations and a clarifying relation between these graphs and Rumin’s complex of differential forms. 相似文献
90.
Vittoria Petrillo Giorgia Alberti Luca Celardo Francesco Cerutti Silvano Franchi Vittorio Mariani 《Central European Journal of Physics》2006,4(2):196-209
The effect of a position measurement on one component of a two-particle wave packet in a regularized space-momentum entangled
state is analyzed. The wave packet interacts in the physical space with a potential barrier. When a position or momentum measurement
is performed on one particle, a consequent strong modification of the dynamics of the other particle occurs. 相似文献