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161.
Molecular Size and Electronic Structure Combined Effects on the Electrogenerated Chemiluminescence of Sulfurated Pyrene‐Cored Dendrimers
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Dr. Giovanni Valenti Dr. Andrea Fiorani Dr. Simone Di Motta Dr. Giacomo Bergamini Prof. Marc Gingras Prof. Paola Ceroni Prof. Fabrizia Negri Prof. Francesco Paolucci Prof. Massimo Marcaccio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2936-2947
The electrochemistry, photophysics, and electrochemically generated chemiluminescence (ECL) of a family of polysulfurated dendrimers with a pyrene core have been thoroughly investigated and complemented by theoretical calculations. The redox and luminescence properties of dendrimers are dependent on the generation number. From low to higher generation it is both easier to reduce and oxidize them and the emission efficiency increases along the family, with respect to the polysulfurated pyrene core. The analysis of such data evidences that the formation of the singlet excited state by cation–anion annihilation is an energy‐deficient process and, thus, the ECL has been justified through the triplet–triplet annihilation pathway. The study of the dynamics of the ECL emission was achieved both experimentally and theoretically by molecular mechanics and quantum chemical calculations. It has allowed rationalization of a possible mechanism and the experimental dependence of the transient ECL on the dendrimer generation. The theoretically calculated Marcus electron‐transfer rate constant compares very well with that obtained by the finite element simulation of the whole ECL mechanism. This highlights the role played by the thioether dendrons in modulating the redox and photophysical properties, responsible for the occurrence and dynamics of the electron transfer involved in the ECL. Thus, the combination of experimental and computational results allows understanding of the dendrimer size dependence of the ECL transient signal as a result of factors affecting the annihilation electron transfer. 相似文献
162.
A systematic study of glycopeptide esterification for the semi‐quantitative determination of sialylation in antibodies
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Álvaro Santana-Mayor Ruth Rodríguez-Ramos Bárbara Socas-Rodríguez Miguel Ángel Rodríguez-Delgado Giovanni D'Orazio 《Electrophoresis》2020,41(20):1768-1775
The separation of 11 phthalic acid ester (PAEs) was carried out by nano-liquid chromatography coupled to ultraviolet and MS detection. Preliminary experiments were achieved in order to select suitable stationary phases and chromatographic conditions. The baseline separation was obtained, for all compounds, with an XBridgeTM C18 column in less than 15 min, working in step gradient mode. The sensitivity of the method was improved by on-column focusing. PAEs were extracted from alcoholic and nonalcoholic beverages using vortex-assisted emulsification dispersive liquid–liquid microextration and natural deep eutectic solvents. The whole method was validated in terms of linearity, sensitivity, precision, recovery, and repeatability. Combination of both off-line sample preparation preconcentration and large injection volume led to obtain LOQs in the range 5–47 ng/mL. The developed nano-LC-UV method was extended to MS detection to confirm the presence of PAEs in some beverages commercialized in different types of packaging. 相似文献
166.
Giovanni Gallavotti 《Journal of statistical physics》2014,157(4-5):743-754
Application of asymptotic freedom to the ultraviolet stability in Euclidean quantum field theories is revisited and illustrated through the hierarchical model making also use of a few technical developments that followed the original works of Wilson on the renormalization group. 相似文献
167.
Elena Molteni Giovanni Onida Giancarlo Cappellini 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(4):98
We study the electronic properties of the Si(001):Uracil, Si(001):Thymine, andSi(001):5-Fluorouracil systems, focusing on the Si dimer-bridging configuration withadsorption governed by carbonyl groups. While the overall structural and electronicproperties are similar, with small differences due to chemical substitutions, much largereffects on the surface band dispersion and bandgap show up as a function of the molecularorientation with respect to the surface. An off-normal orientation of the molecular planesis favored, showing larger bandgap and lower total energy than the upright position. Wealso analyze the localization of gap-edge occupied and unoccupied surface states. 相似文献
168.
Giovanni Stracquadanio Elisa Pappalardo Panos M. Pardalos 《Journal of Optimization Theory and Applications》2012,155(3):1008-1024
The design of circular antenna arrays is a challenging optimization problem, which requires ad-hoc methods to fulfill the engineering requirements. In this work, we introduce the Mesh Adaptive Basin Hopping algorithm to tackle such problem effectively; the experimental results show that the new approach proposed outperforms the state-of-the-art methods, both in terms of quality of the solutions and computational efficiency. 相似文献
169.
Giovanni Papandrea 《合成通讯》2013,43(6):858-865
This article describes a new route to peptidosulfonamide. Our study shows how sulfinamides were first obtained via nucleophilic cleavage of 3,6‐dihydrothiazine‐1‐oxide system and how the products can be subjected to oxidation with m‐chloroperbenzoic acid to give sulfonamides in good yield. 相似文献
170.
Giovanni Alessandrini 《Journal of Mathematical Analysis and Applications》2012,386(2):669-676
We prove that solutions to elliptic equations in two variables in divergence form, possibly non-self-adjoint and with lower order terms, satisfy the strong unique continuation property. 相似文献