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Dr. Georgios Rotas Prof. Dr. Nikos Tagmatarchis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1206-1214
Energy conversion schemes have attracted considerable attention in recent years. A large amount of research effort has focused on fullerenes, particularly C60 and its derivatives, as suitable electron acceptors, owing to their outstanding properties. In this context, C59N‐based donor–acceptor systems have lately attracted attention, owing to their exceptional energy‐and electron‐transfer properties. As a result, chemical derivatization of C59N plays an important role in the realization of the aforementioned systems. The current Minireview aims to familiarize researchers with the main aspects of azafullerene synthesis, chemistry, and photophysical properties, while it mainly focuses on the synthetic methodologies employed for as well as on energy conversion schemes of azafullerene‐based donor–acceptor systems. 相似文献
164.
Dr. Dimitris Kalaitzakis Myron Triantafyllakis Ioanna Alexopoulou Manolis Sofiadis Prof. Dr. Georgios Vassilikogiannakis 《Angewandte Chemie (International ed. in English)》2014,53(48):13201-13205
A highly efficient one‐pot transformation of readily accessible furans into 4‐hydroxy‐2‐cyclopentenones in H2O, using singlet oxygen as oxidant, has been developed. 相似文献
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We give, using an explicit expression obtained in (Jones V, Ann Math 126:335, 1987), a basic hypergeometric representation of the HOMFLY polynomial of (n, m) torus knots, and present a number of equivalent expressions, all related by Heine’s transformations. Using this result, the \({ (m, n) \leftrightarrow (n, m)}\) symmetry and the leading polynomial at large N are explicit. We show the latter to be the Wilson loop of 2d Yang–Mills theory on the plane. In addition, after taking one winding to infinity, it becomes the Wilson loop in the zero instanton sector of the 2d Yang–Mills theory, which is known to give averages of Wilson loops in \({\mathcal{N}}\) = 4 SYM theory. We also give, using matrix models, an interpretation of the HOMFLY polynomial and the corresponding Jones–Rosso representation in terms of q-harmonic oscillators. 相似文献
167.
This paper introduces a general continuous-time mathematical framework for solution of dynamic mean–variance control problems. We obtain theoretical results for two classes of functionals: the first one depends on the whole trajectory of the controlled process and the second one is based on its terminal-time value. These results enable the development of numerical methods for mean–variance problems for a pre-determined risk-aversion coefficient. We apply them to study optimal trading strategies pursued by fund managers in response to various types of compensation schemes. In particular, we examine the effects of continuous monitoring and scheme’s symmetry on trading behavior and fund performance. 相似文献
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Eleftheria Roumeli Angelina Tsiapranta Eleni Pavlidou Georgios Vourlias Kyriakos Kachrimanis Dimitrios Bikiaris Konstantinos Chrissafis 《Journal of Thermal Analysis and Calorimetry》2013,111(3):2109-2115
Thermal analysis is an essential, analytic tool used in preliminary studies and preparation of new pharmaceutical formulations. This study was performed to investigate the possible interactions between trandolapril and three commonly used natural excipients, namely α-lactose monohydrate, microcrystalline cellulose, and pregelatinized starch. The compatibility studies were carried out using thermoanalytic along with other complementary techniques. Differential scanning calorimetry and thermogravimetric analysis have proved that trandolapril is fully compatible with all the studied excipients until 100 °C. The complementary techniques used in this study were X-ray powder diffraction, Fourier transform-infrared spectroscopy, and scanning electron microscopy which confirmed the findings of thermal analysis. 相似文献
170.
Nele-Johanna Hempel Padryk Merkl Matthias Manne Knopp Ragna Berthelsen Alexandra Teleki Anders Kragh Hansen Georgios A. Sotiriou Korbinian Lbmann 《Molecules (Basel, Switzerland)》2021,26(13)
Laser radiation has been shown to be a promising approach for in situ amorphization, i.e., drug amorphization inside the final dosage form. Upon exposure to laser radiation, elevated temperatures in the compacts are obtained. At temperatures above the glass transition temperature (Tg) of the polymer, the drug dissolves into the mobile polymer. Hence, the dissolution kinetics are dependent on the viscosity of the polymer, indirectly determined by the molecular weight (Mw) of the polymer, the solubility of the drug in the polymer, the particle size of the drug and the molecular size of the drug. Using compacts containing 30 wt% of the drug celecoxib (CCX), 69.25 wt% of three different Mw of polyvinylpyrrolidone (PVP: PVP12, PVP17 or PVP25), 0.25 wt% plasmonic nanoaggregates (PNs) and 0.5 wt% lubricant, the effect of the polymer Mw on the dissolution kinetics upon exposure to laser radiation was investigated. Furthermore, the effect of the model drug on the dissolution kinetics was investigated using compacts containing 30 wt% of three different drugs (CCX, indomethacin (IND) and naproxen (NAP)), 69.25 wt% PVP12, 0.25 wt% PN and 0.5 wt% lubricant. In perfect correlation to the Noyes–Whitney equation, this study showed that the use of PVP with the lowest viscosity, i.e., the lowest Mw (here PVP12), led to the fastest rate of amorphization compared to PVP17 and PVP25. Furthermore, NAP showed the fastest rate of amorphization, followed by IND and CCX in PVP12 due to its high solubility and small molecular size. 相似文献