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Dougherty Sherwood posted an update 2 days, 1 hour ago
Electronic metal-support interactions (EMSIs) comprise an area of intense study, the manipulation of which is of paramount importance in the improvement of heterogeneous metal nanoparticle (NP) supported catalysts. EMSI is the transfer of charge from the support to NP, enabling more effective adsorption and interaction of reactants during catalysis. Ru NPs on CuO supports show different levels of EMSI (via charge transfer) depending on their crystal structure, with multiple twinned NPs showing greater potential for EMSI. We use magnetron-assisted gas phase aggregation for the synthesis of batches of Ru NPs with different populations of single crystal and multiple twinned nanoparticles, which were deposited on CuO nanowires (NWs). Batimastat price The surface charging of the Ru-CuO catalysts was investigated by Kelvin probe force microscopy (KPFM) and X-ray photoelectron spectroscopy (XPS). By doubling the population of multiple twinned NPs, the surface potential of the Ru-CuO catalysts increases roughly 4 times, coinciding with a similar increase in the amount of Ru4+. Therefore, tuning the amount of EMSI in a catalyst is possible through changing the population of multiple twinned Ru NPs in the catalyst. Increasing the amount of multiple twin NPs resulted in improved activity in the oxygen evolution reaction (a roughly 2.5 times decrease in the overpotentials when the population of multiple twinned NPs is increased) and better catalyst stability. This improvement is attributed to the fact that the multiple twin NPs maintained a metallic character under oxidation conditions (unlike single crystal NPs) due to the EMSI between the NP and support.Covering July 2012 to December 2019Over the last seven years, expanding research efforts focused on sesterterpenoids has led to the isolation, identification, and characterization of numerous structurally novel and biologically active sesterterpenoids. These newly reported sesterterpenoids provide diverse structures that often incorporate unprecedented ring systems and new carbon skeletons, as well as unusual functional group arrays. Biological activities of potential biomedical importance including suppression of cancer cell growth, inhibition of enzymatic activity, and modulation of receptor signaling, as well as ecologically important functions such as antimicrobial effects and deterrence of herbivorous insects have been associated with a variety of sesterterpenoids. There has also been a rapid growth in our knowledge of the genomics, enzymology, and specific pathways associated with sesterterpene biosynthesis. This has opened up new opportunities for future sesterterpene discovery and diversification through the expression of new cryptic metabolites and the engineered manipulation of associated biosynthetic machinery and processes. In this paper we reviewed 498 new sesterterpenoids, including their structures, source organisms, country of origin, relevant bioactivities, and biosynthesis.Gene vectors are nucleic acids that carry genetic materials or gene editing devices into cells to exert the sustained production of therapeutic proteins or to correct erroneous genes of the cells. However, the cell membrane sets a barrier for the entry of nucleic acid molecules, and nucleic acids are easily degraded or neutralized when they are externally administered into the body. Carriers to encapsulate, protect and deliver nucleic acid molecules therefore are essential for clinical applications of gene therapy. The secreted organelles, exosomes, which naturally mediate the communications between cells, have been engineered to encapsulate and deliver nucleic acids to the desired tissues and cells. The fusion of exosomes with liposomes can increase the loading capacity and also retain the targeting capability of exosomes. Altogether, this review summarizes the most recent designs of exosome-based applications for gene delivery and their future perspectives in gene therapy.Two NNN pincer complexes of Cu(ii) and Ni(ii) with BPIMe- [BPIMe- = 1,3-bis((6-methylpyridin-2-yl)imino)isoindolin-2-ide] have been prepared and characterized structurally, spectroscopically, and electrochemically. The single crystal structures of the two complexes confirmed their distorted trigonal bipyramidal geometry attained by three equatorial N-atoms from the ligand and two axially positioned water molecules to give [Cu(BPIMe)(H2O)2]ClO4 and [Ni(BPIMe)(H2O)2]ClO4. Electrochemical studies of Cu(ii) and Ni(ii) complexes have been performed in acetonitrile to identify metal-based and ligand-based redox activity. When subjected to a saturated CO2 atmosphere, both complexes displayed catalytic activity for the reduction of CO2 with the Cu(ii) complex displaying higher activity than the Ni(ii) analogue. However, both complexes were shown to decompose into catalytically active heterogeneous materials on the electrode surface over extended reductive electrolysis periods. Surface analysis of these materials using energy dispersive spectroscopy as well as their physical appearance suggests the reductive deposition of copper and nickel metal on the electrode surface. Electrocatalysis and decomposition are proposed to be triggered by ligand reduction, where complex stability is believed to be tied to fluxional ligand coordination in the reduced state.In the present work, we report the design and fabrication of a copper-containing ionic liquid supported magnetic nanocatalyst via a convenient and straightforward synthetic approach for the formation of 2-phenylquinazolin-4(3H)-ones using o-aminobenzamide and benzaldehydes as the reaction partners. The successful formation and properties of the as-prepared catalyst have been thoroughly investigated using diverse physico-chemical techniques including FT-IR, XRD, FE-SEM, TEM, ICP, VSM, BET and TGA. Using this nanocatalytic system, a variety of 2-phenylquinazolin-4(3H)-ones are synthesized in excellent yields with operational ease and short reaction times in an environmentally preferable solvent under open air and without using any external oxidizing agent. Besides, the catalyst possessed facile magnetic recoverability and remarkable reusability for six consecutive runs without any appreciable decrease in the catalytic efficiency.