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21.
Vassilios Fessatidis Frank A. CorvinoJay D. Mancini William J. MassanoSamuel P. Bowen 《Physics letters. A》2012,376(4):573-578
The coupling of a two-level system to quantized boson modes has been the focus of many researchers for a number of years. Applications to exciton motion, molecular polaron formation, chaos in quantum systems as well as a number of other effects in condensed matter physics have also been studied. Here we investigate the interaction of bosonic modes with a two-level fermionic system. This quantum system is used as a testing ground for a recently developed Generalized Moments Expansion, GMX(m,n), of which the well-known Connected Moments Expansion (CMX) and Alternate Moments Expansion (AMX) are special cases. The convergence and viability of this scheme are discussed and comparisons are made with a related Canonical Sequence Method (CSM) as well as a Lanczos tridiagonal truncation scheme. 相似文献
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The importance of the anthracycline antibiotics as anticancer agents, particularly Adriamycin, is well established. It is generally accepted that Adriamycin has the broadest spectrum of activity among all the anticancer agents in clinical use1. 相似文献
25.
Daiana T. Mancini Eugenio F. Souza Melissa S. Caetano Teodorico C. Ramalho 《Magnetic resonance in chemistry : MRC》2014,52(4):129-137
The phenylbenzothiazole compounds show antitumor properties and are highly selective. In this paper, the 99Tc chemical shifts based on the (99mTc)(CO)3(NNO) complex conjugated to the antitumor agent 2‐(4′‐aminophenyl)benzothiazole are reported. Thermal and solvent effects were studied computationally by quantum‐chemical methods, using the density functional theory (DFT) (DFT level BPW91/aug‐cc‐pVTZ for the Tc and BPW91/IGLO‐II for the other atoms) to compute the NMR parameters for the complex. We have calculated the 99Tc NMR chemical shifts of the complex in gas phase and solution using different solvation models (polarizable continuum model and explicit solvation). To evaluate the thermal effect, molecular dynamics simulations were carried, using the atom‐centered density matrix propagation method at the DFT level (BP86/LanL2dz). The results highlight that the 99Tc NMR spectroscopy can be a promising technique for structural investigation of biomolecules, at the molecular level, in different environments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
26.
The Adimurthi–Druet [1] inequality is an improvement of the standard Moser–Trudinger inequality by adding a -type perturbation, quantified by , where is the first Dirichlet eigenvalue of Δ on a smooth bounded domain. It is known [3], [10], [14], [19] that this inequality admits extremal functions, when the perturbation parameter α is small. By contrast, we prove here that the Adimurthi–Druet inequality does not admit any extremal, when the perturbation parameter α approaches . Our result is based on sharp expansions of the Dirichlet energy for blowing sequences of solutions of the corresponding Euler–Lagrange equation, which take into account the fact that the problem becomes singular as . 相似文献
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Dr. Annalisa Mancini Dr. M. Carla Aragoni Dr. Neil Bricklebank Dr. Carlo Castellano Prof. Francesco Demartin Prof. Francesco Isaia Prof. Vito Lippolis Dr. Anna Pintus Dr. Massimiliano Arca 《化学:亚洲杂志》2013,8(3):639-647
The reactions of 4,5,6,7‐tetrathiocino‐[1,2‐b:3,4‐b′]‐1,3,8,10‐tetrasubstituted‐diimidazolyl‐2,9‐dithiones (R2,R′2‐todit; 1 : R=R′=Et; 2 : R=R′=Ph; 3 : R=Et, R′=Ph) with Br2 exclusively afforded 1:1 and 1:2 “T‐shaped” adducts, as established by FT‐Raman spectroscopy and single‐crystal X‐ray diffraction in the case of complex 1? 2 Br2. On the other hand, the reactions of compounds 1 – 3 with molecular I2 provided charge‐transfer (CT) “spoke” adducts, among which the solvated species 3? 2 I2 ? (1?x)I2 ? x CH2Cl2 (x=0.94) and ( 3 )2 ? 7 I2 ? x CH2Cl2, (x=0.66) were structurally characterized. The nature of all of the reaction products was elucidated based on elemental analysis and FT‐Raman spectroscopy and supported by theoretical calculations at the DFT level. 相似文献
28.
Marta Martino Andrea Salvadori Federico Lazzari Lorenzo Paoloni Surajit Nandi Giordano Mancini Vincenzo Barone Sergio Rampino 《Journal of computational chemistry》2020,41(13):1310-1323
The virtual-reality framework AVATAR (Advanced Virtual Approach to Topological Analysis of Reactivity) for the immersive exploration of potential-energy landscapes is presented. AVATAR is based on modern consumer-grade virtual-reality technology and builds on two key concepts: (a) the reduction of the dimensionality of the potential-energy surface to two process-tailored, physically meaningful generalized coordinates, and (b) the analogy between the evolution of a chemical process and a pathway through valleys (potential wells) and mountain passes (saddle points) of the associated potential energy landscape. Examples including the discovery of competitive reaction paths in simple A + BC collisional systems and the interconversion between conformers in ring-puckering motions of flexible rings highlight the innovation potential that augmented and virtual reality convey for teaching, training, and supporting research in chemistry. 相似文献
29.
Emília Valena Ferreira de Arago Luca Mancini Noelia Faginas-Lago Marzio Rosi Dimitrios Skouteris Fernando Pirani 《Molecules (Basel, Switzerland)》2022,27(7)
The reaction between the cyano radical CN and cyanoacetylene molecule HCN is of great interest in different astronomical fields, from star-forming regions to planetary atmospheres. In this work, we present a new synergistic theoretical approach for the derivation of the rate coefficient for gas phase neutral-neutral reactions. Statistic RRKM calculations on the Potential Energy Surface are coupled with a semiempirical analysis of the initial bimolecular interaction. The value of the rate coefficient for the HCN + CN → H + NCCCCN reaction obtained with this method is compared with previous theoretical and experimental investigations, showing strengths and weaknesses of the new presented approach. 相似文献
30.
It is shown that radiation pressure can be profitably used to entangle macroscopic oscillators like movable mirrors, using present technology. We prove a new sufficient criterion for entanglement and show that the achievable entanglement is robust against thermal noise. Its signature can be revealed using common optomechanical readout apparatus. 相似文献