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901.
Potential Analysis - The upper escape rate for a Markov process is a natural partial generalization of the celebrated Khintchine’s law of the iterated logarithm. In this article, we present a... 相似文献
902.
Massimo Brochetta Tania Borsari Andrea Gandini Sandip Porey Arghya Deb Emanuele Casali Arka Chakraborty Prof. Dr. Giuseppe Zanoni Prof. Dr. Debabrata Maiti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(3):750-753
A silver(I) catalyzed regioselective trifluoromethylation of allenes using Langlois's salt (NaOSOCF3) is demonstrated. This transformation enables direct expedient access to α-trifluoromethylated acroleins, which are valuable synthons for a number of pharmaceuticals and agrochemicals containing vinyl-CF3 moieties. Versatility of this trifluoromethylation method has been established with good yield and excellent regioselectivity. Preliminary experiments and computational studies were carried out to elucidate the mechanistic insight of this protocol. 相似文献
903.
Michaela König Dr. Massimo Rigo Nicolas Chaoui Trung Tran Ngoc Dr. Jan Dirk Epping Dr. Johannes Schmidt Dr. Pradip Pachfule Meng-Yang Ye Dr. Matthias Trunk Prof. Johannes F. Teichert Prof. Matthias Drieß Prof. Arne Thomas 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20002-20006
An iridium dihydride pincer complex [IrH2(POCOP)] is immobilized in a hydroxy-functionalized microporous polymer network using the concepts of surface organometallic chemistry. The introduction of this novel, truly innocent support with remote OH-groups enables the formation of isolated active metal sites embedded in a chemically robust and highly inert environment. The catalyst maintained high porosity and without prior activation exhibited efficacy in the gas phase hydrogenation of ethene and propene at room temperature and low pressure. The catalyst can be recycled for at least four times. 相似文献
904.
905.
Mine Sarac Massimiliano Solazzi Edoardo Sotgiu Massimo Bergamasco Antonio Frisoli 《Meccanica》2017,52(3):749-761
This study presents the design and the kinematic optimization of a novel, underactuated, linkage-based robotic hand exoskeleton to assist users performing grasping tasks. The device has been designed to apply only normal forces to the finger phalanges during flexion/extension of the fingers, while providing automatic adaptability for different finger sizes. Thus, the easiness of the attachment to the user’s fingers and better comfort have been ensured. The analyses of the device kinematic pose, statics and stability of grasp have been performed. These analyses have been used to optimize the link lengths of the mechanism, ensuring that a reasonable range of motion is satisfied while maximizing the force transmission on the finger joints. Finally, the usability of a prototype with multiple fingers has been tested during grasping tasks with different objects. 相似文献
906.
Alessandra Pinna Luca Malfatti Massimo Piccinini Paolo Falcaro Plinio Innocenzi 《Journal of synchrotron radiation》2012,19(4):586-590
The protection of organic and hybrid organic–inorganic materials from X‐ray damage is a fundamental technological issue for broadening the range of applications of these materials. In the present article it is shown that doping hybrid films with fullerenes C60 gives a significant reduction of damage upon exposure to hard X‐rays generated by a synchrotron source. At low X‐ray dose the fullerene molecules act as `radical scavengers', considerably reducing the degradation of organic species triggered by radical formation. At higher doses the gradual hydroxylation of the fullerenes converts C60 into fullerol and a bleaching of the radical sinking properties is observed. 相似文献
907.
Zaid M. Abbas Mohammed M. Khani Massimo Tawfilas Zachary M. Marsh Morgan Stefik Brian C. Benicewicz 《Journal of polymer science. Part A, Polymer chemistry》2020,58(3):417-427
Reversible addition-fragmentation chain transfer (RAFT) polymerization of 2,3-dimethyl-1,3-butadiene (DMB) in solution and on the surface of silica nanoparticles was investigated and PDMB-grafted silica nanoparticles (PDMB-g-SiO2 NPs) with different chain densities and molecular weights were prepared. The kinetic studies of DMB polymerization mediated by silica anchored RAFT agents at different graft densities were investigated and compared to the polymerization mediated by the corresponding free RAFT agent. The PDMB-g-SiO2 NPs were cured to prepare rubbery films and obtain matrix-free nanocomposites, which exhibited a good dispersion of silica nanoparticles and improved mechanical properties compared to the unfilled crosslinked rubber. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 417–427 相似文献
908.
Massimo Boiocchi Dr. Luigi Fabbrizzi Prof. Mauro Garolfi Dr. Maurizio Licchelli Prof. Lorenzo Mosca Dr. Cristina Zanini Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(42):11288-11297
Copper(II) azacyclam complexes 3 2+ and 4 2+ were obtained through a metal‐templated procedure involving the pertinent open‐chain tetramine, formaldehyde and a phenylurea derivative as a locking fragment. Both metal complexes can establish interactions with anions through the metal centre and the amide NH group. Equilibrium studies in DMSO by a spectrophotometric titration technique were carried out to assess the affinity of 3 2+ and 4 2+ towards anions. While the NH group of an amide model compound and the metal centre of the plain CuII(azacyclam)2+ complex do not interact at all with anions, 3 2+ and 4 2+ establish strong interactions with oxo anions, profiting from a pronounced cooperative effect. In particular, 1) they form stable 1:1 and 1:2 complexes with H2PO4? ions in a stepwise mode with both hydrogen‐bonding and metal–ligand interactions, and 2) in the presence of CH3COO?, they undergo deprotonation of the amido NH group and thus profit from axial coordination of the partially negatively charged carbonyl oxygen atom in a scorpionate binding mode. 相似文献
909.
Francesca?Gladiali Massimo?GrossiEmail author Christophe?Troestler 《Calculus of Variations and Partial Differential Equations》2018,57(2):53
In this paper we establish existence of radial and nonradial solutions to the system where \(F_1,F_2\) are nonlinearities with critical behavior.
相似文献
$$\begin{aligned} {\left\{ \begin{array}{ll} \displaystyle -\Delta u_1 = F_1(u_1,u_2) &{}\quad \text {in }{\mathbb R}^N,\\ -\Delta u_2 = F_2(u_1,u_2) &{}\quad \text {in }{\mathbb R}^N,\\ u_1\geqslant 0,\ u_2\geqslant 0 &{}\quad \text {in }{\mathbb R}^N,\\ u_1,u_2\in D^{1,2}({\mathbb R}^N), \end{array}\right. } \end{aligned}$$
910.
Clara Antonucci Massimo Gobbino Matteo Migliorini Nicola Picenni 《Comptes Rendus Mathematique》2018,356(8):859-864
We consider the family of non-local and non-convex functionals introduced by H. Brézis and H.-M. Nguyen in a recent paper. These functionals Gamma-converge to a multiple of the Sobolev norm or the total variation, depending on a summability exponent, but the exact values of the constants are unknown in many cases.We describe a new approach to the Gamma-convergence result that leads in some special cases to the exact value of the constants, and to the existence of smooth recovery families. 相似文献