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991.
992.
993.
Christos Tsiamantas Sunbum Kwon Joseph M. Rogers Cline Douat Ivan Huc Hiroaki Suga 《Angewandte Chemie (International ed. in English)》2020,59(12):4860-4864
Derivatives of 4‐aminomethyl‐l ‐phenylalanine with aromatic oligoamide foldamers as sidechain appendages were successfully charged on tRNA by means of flexizymes. Their subsequent incorporation both at the C‐terminus of, and within, peptide sequences by the ribosome, was demonstrated. These results expand the registry of chemical structures tolerated by the ribosome to sidechains significantly larger and more structurally defined than previously demonstrated. 相似文献
994.
Sergi Garcia-Segura Alec Brockway Nienhauser Ana S. Fajardo Rishabh Bansal Christian L. Conrad John D. Fortner Mariana Marcos-Hernández Tanya Rogers Dino Villagran Michael S. Wong Paul Westerhoff 《Current Opinion in Electrochemistry》2020
Electrochemical water treatment is one of the key topics of environmental electrochemistry. Identifying electrocatalytic materials capable of electrogenerating high oxidant species in situ seems to have catalyzed researchers’ interest in these processes. While most studies have focused on ideal lab-made solutions, translation to higher technology readiness levels and commercialization requires reframing research questions in context of real water matrices. In this current opinion, we discuss disconnects that may occur when focusing on synthetic solution treatment rather than on real waters. Future research can fill the gaps identified herein, thus facilitating application of electrochemical water treatment technologies. 相似文献
995.
Antonios M. Xenakis Steven J. Lind Peter K. Stansby Benedict D. Rogers 《国际流体数值方法杂志》2020,92(7):703-726
An incompressible smoothed particle hydrodynamics (ISPH) method is developed for the modeling of multiphase Newtonian and inelastic non-Newtonian flows at low density ratios. This new method is the multiphase extension of Xenakis et al, J. Non-Newtonian Fluid Mech., 218, 1-15, which has been shown to be stable and accurate, with a virtually noise-free pressure field for single-phase non-Newtonian flows. For the validation of the method a semi-analytical solution of a two-phase Newtonian/non-Newtonian (inelastic) Poiseuille flow is derived. The developed method is also compared with the benchmark multiphase case of the Rayleigh Taylor instability and a submarine landslide, thereby demonstrating capability in both Newtonian/Newtonian and Newtonian/non-Newtonian two-phase applications. Comparisons with analytical solutions, experimental and previously published results are conducted and show that the proposed methodology can accurately predict the free-surface and interface profiles of complex incompressible multi-phase flows at low-density ratios relevant, for example, to geophysical environmental applications. 相似文献
996.
Philip A. Ernst L.C.G. Rogers Quan Zhou 《Stochastic Processes and their Applications》2017,127(12):3913-3927
Suppose you have one unit of stock, currently worth 1, which you must sell before time . The Optional Sampling Theorem tells us that whatever stopping time we choose to sell, the expected discounted value we get when we sell will be 1. Suppose however that we are able to see units of time into the future, and base our stopping rule on that; we should be able to do better than expected value 1. But how much better can we do? And how would we exploit the additional information? The optimal solution to this problem will never be found, but in this paper we establish remarkably close bounds on the value of the problem, and we derive a fairly simple exercise rule that manages to extract most of the value of foresight. 相似文献
997.
It is shown that the complete exceptionality condition for discontinuity waves associated with a second-order non-linear hyperbolic equation of the form
相似文献
998.
Benzene Solubility in Ionic Liquids: Working Toward an Understanding of Liquid Clathrate Formation 下载免费PDF全文
Prof. Dr. Jorge F. B. Pereira Luis A. Flores Dr. Hui Wang Prof. Dr. Robin D. Rogers 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(47):15482-15492
The solubility of benzene in 15 imidazolium, pyrrolidinium, pyridinium, and piperidinium ionic liquids has been determined; the resulting, benzene‐saturated ionic liquid solutions, also known as liquid clathrates, were examined with 1H and 19F nuclear magnetic resonance spectroscopy to try and understand the molecular interactions that control liquid clathrate formation. The results suggest that benzene interacts primarily with the cation of the ionic liquid, and that liquid clathrate formation (and benzene solubility) is controlled by the strength of the cation–anion interactions, that is, the stronger the cation–anion interaction, the lower the benzene solubility. Other factors that were determined to be important in the final amount of benzene in any given liquid clathrate phase included attractive interactions between the anion and benzene (when significant), and larger steric or free volume demands of the ions, both of which lead to greater benzene solubility. 相似文献
999.
Daugirdas Tomas Racys Julian Eastoe Per-Ola Norrby Isabelle Grillo Sarah E. Rogers Guy C. Lloyd-Jones 《Chemical science》2015,6(10):5793-5801
Under optimised conditions, the Trost modular ligand (TML) series induces high levels of asymmetric induction in an extraordinarily wide range of reactions involving palladium π-allyl intermediates. Prior mechanistic investigations into reactions involving Pd-η
3-C6H9 intermediates have focussed on the monomeric 13-membered ring formed via P,P-chelation of the ligand to Pd. However, it is also recognised that ring-opening oligomerisation provides a pool of high nuclearity Pd-η
3-C6H9 species that, by affording a low level, or even the opposite sense, of asymmetric induction relative to the mononuclear species, are responsible for a reduction in selectivity under non-optimised conditions. Herein we describe an investigation by NMR spectroscopy, molecular mechanics, molecular dynamics, and small-angle neutron scattering (SANS), of a Pd-η
3-C6H9 cation bearing the 1,2-diaminocyclohexane TML ligand (2). Using both nondeuterated and perdeuterated (D47) isotopologues of the resulting complexes ([1]+), we show that a two-stage oligomerisation-aggregation process forms self assembled cylindrical aggregates of very high nuclearity (up to 56 Pd centres). We also investigate how concentration, solvent and counter-anion all modulate the extent of oligomerisation. 相似文献
1000.
Experimental studies of steady streaming flows are presented for spheroids of various aspect ratios oscillating in a viscous
fluid along their axis of symmetry at Reynolds numbers up to 150 and normalized oscillation amplitudes up to 1.2. The steady
streaming component of the flow is visualized using phase-locked particle pathline images along the central plane of the spheroid.
The extent of the inner region of the flow, characterized by the distance to the stagnation points, appears to depend on a
length scale based on the spheroid aspect ratio and equivalent radius. Spheroids were also oscillated at a nonzero angle with
respect to their axis of symmetry. The angular displacement of the stagnation points on the surface of these obliquely oscillated
spheroids is related to the aspect ratio and the angle of oscillation. 相似文献
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