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171.
Marta Mameli M. Carla Aragoni Dr. Massimiliano Arca Dr. Claudia Caltagirone Dr. Francesco Demartin Prof. Giovanna Farruggia Dr. Greta De Filippo Francesco A. Devillanova Prof. Alessandra Garau Dr. Francesco Isaia Prof. Vito Lippolis Prof. Dr. Sergio Murgia Dr. Luca Prodi Prof. Dr. Anna Pintus Nelsi Zaccheroni Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(3):919-930
In spite of the fact that cadmium(II) has been recognized as a highly toxic element and that excessive exposure to this metal ion has been reported to have many adverse effects on human health, very few selective and specific fluorescent probes are available for imaging Cd2+ in living cells. Herein, we report the spectroscopic and photochemical characterization of 5‐(5‐chloro‐8‐hydroxyquinolinylmethyl)‐2,8‐dithia‐5‐aza‐2,6‐pyridinophane ( L ) as a fluorescent sensor for the selective imaging of Cd2+ in living cells. In particular, the response of L to Cd2+ was first assessed in aqueous solutions, sodium dodecyl sulfate micelles, and liposomes, and subsequently in living cells by fluorescence microscopy techniques. Cytofluorimetric analyses of leukemic HL‐60 cells loaded with L also allowed evaluation of the toxicity of the probe and the selective analysis of its intracellular fluorescence in the presence of Cd2+. Furthermore, the 1:1 complex species [Cd( L )H2O]2+ responsible for the OFF–ON chelation enhancement of fluorescence (CHEF) effect on L was structurally characterized; time‐dependent DFT calculations allowed the prediction of theoretical excitations, which were comparable with the experimental ones. 相似文献
172.
Andrews PC Brown DH Fraser BH Gorham NT Junk PC Massi M St Pierre TG Skelton BW Woodward RC 《Dalton transactions (Cambridge, England : 2003)》2010,39(46):11227-11234
Three pentanuclear lanthanoid hydroxo clusters of composition [Ln(OH)(5)(abzm)(10)], where Ln = Eu, Tb, Ho and abzm = di(4-allyloxy)benzoylmethanide, have been prepared. The structures have been characterised by means of IR, Raman, elemental analyses and X-ray diffraction, showing a pyramidal square-based cluster core. The clusters (Tb and Ho) exhibit Curie-Weiss Law behaviour, displaying antiferromagnetic ordering at low temperatures. The emission properties of the Eu cluster demonstrate the abzm(-) ligand is an efficient antenna (λ(ex) = 420 nm) only for the sensitisation of Eu luminescence in the visible range, via energy transfer to the (5)D(0) state of the trivalent metal. The clusters have been reacted in the presence of methyl methacrylate and azobisisobutyronitrile to prepare reinforced polymers via radical polymerisation. The obtained materials exhibit swelling upon immersion into organic solvents up to ≈ 110% of their original size, in agreement with the presence of cluster-crosslinked polymeric chains. Also, no loss of transparency was observed in the preparation of the materials. The characteristic red emission of the Eu cluster in also retained in the polymeric material. 相似文献
173.
In this note, we study the non-linear evolution problem $dY_t = -A Y_t dt + B(Y_t) dX_t,$ where $XIn this note, we study the non-linear evolution problem
where is a -H?lder continuous function of the time parameter, with values in a distribution space, and the generator of an analytical semigroup. Then, we will give some sharp conditions on in order to solve the above equation in a function space, first in the linear case (for any value of in ), and then when satisfies some Lipschitz type conditions (for ). The solution of the evolution problem will be understood in the mild sense, and the integrals involved in that definition will be of Young type. 相似文献
174.
Francesco Caravenna Giambattista Giacomin Massimiliano Gubinelli 《Journal of statistical physics》2006,122(4):799-832
We consider a model of a random copolymer at a selective interface which undergoes a localization/delocalization transition. In spite of the several rigorous results available for this model,
the theoretical characterization of the phase transition has remained elusive and there is still no agreement about several
important issues, for example the behavior of the polymer near the phase transition line. From a rigorous viewpoint non coinciding
upper and lower bounds on the critical line are known.
In this paper we combine numerical computations with rigorous arguments to get to a better understanding of the phase diagram.
Our main results include:
2000 MSC: 60K37, 82B44, 82B80 相似文献
– | Various numerical observations that suggest that the critical line lies strictly in between the two bounds. |
– | A rigorous statistical test based on concentration inequalities and super–additivity, for determining whether a given point of the phase diagram is in the localized phase. This is applied in particular to show that, with a very low level of error, the lower bound does not coincide with the critical line. |
– | An analysis of the precise asymptotic behavior of the partition function in the delocalized phase, with particular attention to the effect of rare atypical stretches in the disorder sequence and on whether or not in the delocalized regime the polymer path has a Brownian scaling. |
– | A new proof of the lower bound on the critical line. This proof relies on a characterization of the localized regime which is more appealing for interpreting the numerical data. |
175.
This paper proposes some Bayesian inferential procedures for the transformed Wiener (TW) process, a new degradation process that has been recently suggested in the literature to describe degradation phenomena where degradation increments are not necessarily positive and depend stochastically on the current degradation level. These procedures have been expressly conceived to allow one incorporating into the inferential process the type of prior information, on meaningful physical characteristics of the observed degradation process, that is generally available in practical settings. Several different prior distributions are proposed, each of them reflecting a specific degree of knowledge on the observed phenomenon. Simple strategies for eliciting the prior hyper‐parameters from the available prior information are provided. Estimates of the TW process parameters and some functions thereof are retrieved by adopting a Monte Carlo Markov Chain technique. Procedures that allow predicting the degradation increment, the useful life of a new unit, and the remaining useful life of a used unit are also provided. Finally, an application is developed on the basis of a set of real degradation measurements of some infrared light‐emitting diodes, widely used in communication systems. The obtained results demonstrate the feasibility of the proposed Bayesian approach and the flexibility of the TW process. 相似文献
176.
Elena Angelini Francesco Galuppi Massimiliano Mella Giorgio Ottaviani 《Journal of Pure and Applied Algebra》2018,222(4):950-965
We prove that a general polynomial vector in three homogeneous variables of degrees has a unique Waring decomposition of rank 7. This is the first new case we are aware of, and likely the last one, after five examples known since the 19th century and the binary case. We prove that there are no identifiable cases among pairs in three homogeneous variables of degree , unless , and we give a lower bound on the number of decompositions. The new example was discovered with Numerical Algebraic Geometry, while its proof needs Nonabelian Apolarity. 相似文献
177.
Lucia Ambrosio M. Carla Aragoni Dr. Massimiliano Arca Dr. Francesco A. Devillanova Prof. Michael B. Hursthouse Prof. Dr. Susanne L. Huth Dr. Francesco Isaia Prof. Vito Lippolis Prof. Dr. Annalisa Mancini Dr. Anna Pintus Dr. 《化学:亚洲杂志》2010,5(6):1395-1406
The tetrabutylammonium (TBA+) salts of square‐planar monoanionic gold complexes of the unsymmetrically substituted Ar,H‐edt2? 1,2‐dithiolene ligands (Ar,H‐edt2?=arylethylene‐1,2‐dithiolato; Ar=phenyl ( 1 ?), 2‐naphthyl ( 2 ?), and 1‐pyrenyl ( 3 ?)) were synthesized and characterized by spectroscopic and electrochemical methods and the corresponding neutral species ( 1 , 2 , and 3 , respectively) were obtained in CH2Cl2 solution at room temperature by diiodine oxidation. The single‐crystal X‐ray diffraction structural data collected for (TBA+)( 2 ?), supported by DFT theoretical calculations, are consistent with the ene‐1,2‐dithiolate form of the ligand and the AuIII oxidation state. All complexes feature intense near‐IR absorptions (at about 1.5 μm) in their neutral states and Vis‐emitting properties in the 400–550 nm range, the energy of which is controlled by the charge of the complex in the case of the 3 ?/ 3 couple. The spectroscopic and electrochemical features of 1 x? and 2 x? (x=0, 1), both in their cis and trans conformations, were investigated by means of DFT and time‐dependent (TD) DFT calculations. 相似文献
178.
179.
In situ and frontal polymerization for the consolidation of porous stones: a unilateral NMR and magnetic resonance imaging study 总被引:1,自引:0,他引:1
Proietti N Capitani D Cozzolino S Valentini M Pedemonte E Princi E Vicini S Segre AL 《The journal of physical chemistry. B》2006,110(47):23719-23728
Consolidation treatment of porous materials was performed by in situ and frontal polymerization of acrylic monomers inside a porous stone. To study the penetration of the polymer inside the stone and its consolidating effects we used water as a contrast agent, detecting its penetration using unilateral NMR and magnetic resonance imaging. All data obtained on differently treated stones were compared with corresponding ones obtained analyzing both untreated stones and stones simply painted with a well-known polymeric protective agent. In situ polymerization of acrylic monomers inside porous stones has been demonstrated to be an extremely powerful consolidating method, whereas thermally initiated frontal polymerization seems less efficient. In both cases the optimal choice of monomers is still open and requires further study. Our data indicate that unilateral NMR represents an inexpensive and simple technique for the non-invasive observation of the water uptake and of the effect of consolidation procedures in porous materials. 相似文献
180.
Complexity-entropy causality plane: A useful approach to quantify the stock market inefficiency 总被引:1,自引:0,他引:1
The complexity-entropy causality plane has been recently introduced as a powerful tool for discriminating Gaussian from non-Gaussian process and different degrees of correlations [O.A. Rosso, H.A. Larrondo, M.T. Martín, A. Plastino, M.A. Fuentes, Distinguishing noise from chaos, Phys. Rev. Lett. 99 (2007) 154102]. We propose to use this representation space to distinguish the stage of stock market development. Our empirical results demonstrate that this statistical physics approach is useful, allowing a more refined classification of stock market dynamics. 相似文献