Carstensenpaul6277

A one-pot synthesized CoRu-CoOX nanocomposite was reported as a magnetically recoverable catalyst for selective hydrogenation of furfural to furfuryl alcohol in water at ambient H2 pressure.A new general de novo synthesis of pharmaceutically important α-aryl β-perfluoroalkyl ketones has been disclosed. Compared with trifluoromethylation-initiated radical 1,2-aryl migration of α,α-diaryl allylic alcohols, this protocol employs a new strategy of biomimetic carbene catalysis to assemble alkene, aldehyde and perfluoroalkyl reagents, providing access to products with excellent flexibility of the aryl unit and perfluoroalkyl group. This method also demonstrates excellent functional group compatibility, including some Grignard reagent sensitive groups.Complex systems such as ecosystems, the climate and stock markets produce emergent behaviour which is capable of undergoing dramatic change when pushed beyond a tipping point. read more Such complex systems display Early Warning Signals in their behaviour when they are close to a tipping point. Here we show that a complex chemical reaction network can also display early warning signals when it is in close proximity to the boundary between oscillatory and steady state concentration behaviours. We identify early warning signals using both an active sensing method, based on the recovery time of an oscillatory response after a perturbation in temperature, and a passive sensing method, based upon a change in the shape of the oscillations. The presence of the early warning signals indicates that complex, dissipative chemical networks can intrinsically sense their proximity to a boundary between behaviours.Herein, we report a novel CuPPc (copper polymeric phthalocyanine)/CF (copper foam) nanoflake material, as precatalyst for the generation of an excellent water oxidation catalyst (WOC). Under optimized conditions, the CuPPc-derived Cu oxide affords a current density of 10 mA cm-2 under an overpotential (η) of 287 mV and sustains for at least 50 h in 1.0 M KOH. The strategy presented here is favorable to develop the electrocatalysts for water splitting.A [4+2] cycloaddition of photogenerated aza-ortho-quinone methides with formaldimines is described for the synthesis of perfluoroalkylated tetrahydroquinazolines. Key to this process is the photocatalytic radical-mediated generation of aza-o-QMs from 2-vinylanilines and perfluoroalkyl radical precursors as well as the in situ release of formaldimines from 1,3,5-triazinanes.The influence of cell number on spectral variability among two different cell types and two states was quantitatively analyzed and evaluated by calculating the similarity distance of the single-cell spectral data obtained from synchrotron infrared microspectroscopy. We found that at least 15 cells are required to achieve robust results with 95% confidence.Colloidal model systems have been extensively used in the studies of various phase transitions, but melting and solid-solid transitions have rarely been explored in monolayer colloidal crystals with anisotropic attractions. Patchy colloidal particles have served as important model systems of atoms and molecules with anisotropic interactions. In this work, we study the melting and solid-solid transitions of two-dimensional crystals composed of Janus colloidal spheres using Langevin dynamics simulation. We discovered a first-order solid-solid transition from a single crystal with uniform stripes to a novel crystal with polycrystalline domains of stripes. The centers of masses of the particles maintain the morphology of a single crystal with long-range translational and bond-orientational orders, but particle orientations form polycrystalline domains of stripes. The stripe domains form by a strain-induced nucleation process via the collective rotation of particles. In addition to this solid-solid transition, the melting transition at a higher temperature follows a two-step Kosterlitz-Thouless-Halperin-Nelson-Young (KTHNY) scenario, similar to most isotropic particle systems.Since being discovered in 2011, a large class of two-dimensional materials, labeled MXenes, has received increased research enthusiasm both theoretically and experimentally due to the unique physical, optical and electrical properties. Here, we prepared few-layered Ti3C2 nanosheets by a facile two-step liquid exfoliation method and, for the first time, demonstrated their intrinsic peroxidase-like activity in a Ti3C2-TMB-H2O2 system. The as-produced Ti3C2 nanosheets, especially after histidine modification, were characterized with excellent water dispersibility, large specific surface area, and high stability, which contribute to their much higher affinity to both substrates when compared to HRP. We have also established the catalytic mechanism whereby Ti3C2 nanosheets, where Ti switched spontaneously from an oxidized to reduced state, promoted the electron transfer from TMB to H2O2. Given the color reaction of Ti3C2 nanosheets, we have fabricated a colorimetric paper-based sensor integrated with a smartphone to detect glucose and an immunoassay to detect IR-β, enabling Ti3C2 nanosheets to be a powerful tool in the biodetection field.Coarse-grained Monte-Carlo simulations of nanogel-polyelectrolyte complexes have been carried out. The results presented here capture two phenomena reported in experiments with real complexes (i) the reduction in size after absorbing just a few chains and (ii) the charge inversion detected through electrophoretic mobility data. Our simulations reveal that charge inversion occurs if the polyelectrolyte charge is large enough. In addition, the distribution of chains inside the nanogel strongly depends on whether charge inversion takes place. It should also be stressed that the chain topology has little influence on most of the properties studied here.To improve the bio-performances of polyetheretherketone (PEEK) for orthopedic applications, submicro-particles of niobium pentoxide (Nb2O5) were synthesized using a sol-gel method, and PEEK/Nb2O5 composites (PNC) with a Nb2O5 content of 25v% (PNC25) and 50v% (PNC50) were fabricated by utilizing a process of pressing-sintering. The results showed that the Nb2O5 particles were not only dispersed in the composites but also exposed on the surface of the composites, which formed submicro-structural surfaces. In addition, the hydrophilicity, surface energy, surface roughness and absorption of proteins of the composites were improved with increasing Nb2O5 content. Moreover, the release of Nb ions with the highest concentration of 5.01 × 10-6 mol L-1 from the composite into the medium displayed no adverse effects on cell proliferation and morphology, indicating no cytotoxicity. Furthermore, compared with PEEK, the composites, especially PNC50, obviously stimulated adhesion and proliferation as well as osteogenic differentiation of bone mesenchymal stem cells of rats.