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991.
992.
Dmitriy Dmitrishin Goran Lesaja Ivan Skrinnik Alex Stokolos 《Physics letters. A》2019,383(16):1871-1878
In the paper two new results that prove typically real and local univalent properties of certain class of rational functions in the unit disc are presented. They provide a theoretical justification of a new method for finding periodic solutions of the discrete vector dynamical systems. The main goal of the paper is to propose and investigate the two-delays generalization of the scheme introduced by Ö. Morgül. The analysis shows that the coefficients in the proposed method can be chosen in a way that improves the admissible range of parameters. The method is elementary and easy to implement. Furthermore, numerical experiments with several well known maps show effectiveness of the control scheme. 相似文献
993.
Alex Man-Hei Yip Justin Shum Dr. Hua-Wei Liu Huipeng Zhou Meiqi Jia Niu Niu Yongxin Li Prof. Cong Yu Prof. Kenneth Kam-Wing Lo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(38):8970-8974
This communication reports novel luminescent rhenium(I)–polypyridine complexes appended with a perylene diimide (PDI) or benzoperylene monoimide (BPMI) moiety through a non-conjugated linker. The photophysical and photochemical properties originating from the interactions of the metal polypyridine and perylene units were exploited to afford new cellular reagents with thiol-sensing capability and excellent photocytotoxic activity. 相似文献
994.
Max Deimling Manuel Kirchhof Barbara Schwager Yaseen Qawasmi Alex Savin Dr. Tina Mühlhäuser Dr. Wolfgang Frey Dr. Birgit Claasen Dr. Angelika Baro Prof. Thomas Sottmann Prof. Sabine Laschat 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(40):9464-9476
The role of liquid confinement on the asymmetric Rh catalysis was studied using the 1,2-addition of phenylboroxine ( 2 ) to N-tosylimine 1 in the presence of [RhCl(C2H4)2]2 and chiral diene ligands as benchmark reaction. To get access to Rh complexes of different polarity, enantiomerically pure C2-symmetric p-substituted 3,6-diphenylbicyclo[3.3.0]octadienes 4 and diastereomerically enriched unsymmetric norbornadienes 5 and 6 carrying either the Evans or the SuperQuat auxiliary were synthesized. A microemulsion containing the equal amounts of H2O/KOH and toluene/reactants was formulated using the hydrophilic sugar surfactant n-octyl β-d -glucopyranoside (C8G1) to mediate the miscibility between the nonpolar reactants and KOH, needed to activate the Rh–diene complex. Prominent features of this organized reaction medium are its temperature insensitivity as well as the presence of water and toluene-rich compartments with a domain size of 55 Å confirmed by small-angle X-ray scattering (SAXS). Although bicyclooctadiene ligands 4 a , b , e performed equally well under homogeneous and microemulsion conditions, ligands 4 c , d gave a different chemoselectivity. For norbornadienes 5 , 6 , however, microemulsions markedly improved conversion and enantioselectivity as well as reaction rate, as was confirmed by kinetic studies using ligand 5 b . 相似文献
995.
Gustav J. Wrmer Bente K. Hansen Johan Palmfeldt Thomas B. Poulsen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(34):12044-12048
Cyclopropenes are an important new addition to the portfolio of functional groups that can be used for bioorthogonal couplings. The inert nature of these highly strained compounds in complex biological systems is almost counterintuitive given their established electrophilic properties in organic synthesis. Here we provide the first demonstration of a cyclopropene that is capable of direct conjugation to protein targets in cells and show that this compound preferentially alkylates the active site cysteine of glutathione S‐transferase omega‐1 (GSTO1). 相似文献
996.
Mahmoud Karimi Paul Croaker Alex Skvortsov Danielle Moreau Nicole Kessissoglou 《国际流体数值方法杂志》2019,90(10):522-543
An efficient hybrid uncorrelated wall plane waves–boundary element method (UWPW-BEM) technique is proposed to predict the flow-induced noise from a structure in low Mach number turbulent flow. Reynolds-averaged Navier-Stokes equations are used to estimate the turbulent boundary layer parameters such as convective velocity, boundary layer thickness, and wall shear stress over the surface of the structure. The spectrum of the wall pressure fluctuations is evaluated from the turbulent boundary layer parameters and by using semi-empirical models from literature. The wall pressure field underneath the turbulent boundary layer is synthesized by realizations of uncorrelated wall plane waves (UWPW). An acoustic BEM solver is then employed to compute the acoustic pressure scattered by the structure from the synthesized wall pressure field. Finally, the acoustic response of the structure in turbulent flow is obtained as an ensemble average of the acoustic pressures due to all realizations of uncorrelated plane waves. To demonstrate the hybrid UWPW-BEM approach, the self-noise generated by a flat plate in turbulent flow with Reynolds number based on chord Rec = 4.9 × 105 is predicted. The results are compared with those obtained from a large eddy simulation (LES)-BEM technique as well as with experimental data from literature. 相似文献
997.
998.
Dr. Jørn Eivind Tungen Dr. Lisa Gerstmann Prof. Dr. Anders Vik Roberta De Matteis Dr. Romain Alexandre Colas Prof. Dr. Jesmond Dalli Prof. Dr. Nan Chiang Prof. Dr. Charles Nicholas Serhan Prof. Dr. Markus Kalesse Prof. Dr. Trond Vidar Hansen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(6):1476-1480
New drugs that can resolve inflammation without immunosuppressive effects are at the medicinal chemistry frontier. Pro-resolving endogenously formed small molecules, that is, the resolvins, are excellent candidates displaying such bioactions. The first total synthesis of the specialized pro-resolving mediator RvD1n−3 DPA has been achieved using the underutilized sp3–sp3 Negishi cross coupling reaction and an alkyne hydrosilylation–protodesilylation protocol. Biological evaluations revealed that this novel mediator displays low nanomolar pro-resolving properties and potently activates the human DRV1/GPR32 receptor. As such, this endogenous natural product is a lead compound for the development of novel immunoresolvents. 相似文献
999.
Jaroslav Borovička Lars Peter Hansen José A. Scheinkman 《Mathematics and Financial Economics》2014,8(4):333-354
We construct shock elasticities that are pricing counterparts to impulse response functions. Recall that impulse response functions measure the importance of next-period shocks for future values of a time series. Shock elasticities measure the contributions to the price and to the expected future cash flow from changes in the exposure to a shock in the next period. They are elasticities because their measurements compute proportionate changes. We show a particularly close link between these objects in environments with Brownian information structures. 相似文献
1000.
Nicole A. Rice Alex Adronov 《Journal of polymer science. Part A, Polymer chemistry》2014,52(19):2738-2747
The ability of a poly(2,7‐carbazole) to disperse three samples of commercially available single‐walled carbon nanotubes (raw HiPCO, purified HiPCO, and CoMoCAT nanotubes) has been investigated. UV–vis‐NIR absorption spectroscopy, photoluminescence mapping, Raman spectroscopy, and atomic force microscopy were used to characterize the dispersions obtained. It was found that the polycarbazole preferentially interacted with semiconducting nanotubes and was efficient at dispersing smaller diameter (under 1.1 nm) carbon nanotubes. Larger diameter nanotubes could be dispersed to form stable suspensions in THF; however, it appeared that there were some small bundles present. It was found that annealing the purified HiPCO nanotubes at high temperature under an inert atmosphere greatly enhanced the ability of the polycarbazole to disperse the nanotubes and remove metallic species. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2738–2747 相似文献