New N-doped graphene-coated molybdenum carbide nanoparticles are prepared, which exhibit superior electrocatalytic activity and long-term durability for the hydrogen evolution reaction.

Auranofin, an FDA-approved arthritis drug, has recently been repurposed as a potential antimicrobial agent; it performed well against many Gram-positive bacteria, including multidrug resistant strains. It is, however, inactive toward Gram-negative bacteria, for which we are in dire need of new therapies. In this work, 40 auranofin analogues were synthesized by varying the structures of the thiol and phosphine ligands, and their activities were tested against ESKAPE pathogens. The study identified compounds that exhibited bacterial inhibition (MIC) and killing (MBC) activities up to 65 folds higher than that of auranofin, making them effective against Gram-negative pathogens. Both thiol and the phosphine structures influence the activities of the analogues. The trimethylphosphine and triethylphosphine ligands gave the highest activities against Gram-negative and Gram-positive bacteria, respectively. Our SAR study revealed that the thiol ligand is also very important, the structure of which can modulate the activities of the AuI complexes for both Gram-negative and Gram-positive bacteria. Moreover, these analogues had mammalian cell toxicities either similar to or lower than that of auranofin.

Silver nanoparticles (Ag NPs) with a mean size of about 90 nm were synthesized by polyol reduction of silver nitrate with ethylene glycol (EG) in the presence of poly(vinyl pyrrolidone) (PVP). The Ag NPs undergo a spontaneous coalescence in the presence of chloride ions even without a traditional sintering process which occurs at a relatively high temperature. Such behavior can cause a rapid decrease in the resistivity of the patterns fabricated by Ag NPs. Conductive silver lines were successfully fabricated on FR-4 substrate using this method. The resulting conductivity of the silver lines reached about 16% of the bulk silver value, which enables fabrication of conductive patterns on some electronic devices.

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Cationic polymerizations of isobutylene (IB) with H 2 O/FeCl 3 /isopropanol (iPrOH) initiating system were conducted in nonpolar hydrocarbon media, such as n-hexane or mixed C 4 fractions at 240 to 20C. This cationic polymerization is a chain-transfer dominated process via highly selective bproton elimination from ACH 3 in the growing chain ends, leading to formation of highly reactive polyisobutylenes (HRPIBs) with large contents (> 90 mol %) of exo-olefin end groups (structure A). The content of structure A remained nearly constant at about 97 mol % during polymerization and isomerization via carbenium ion rearrangement could be suppressed in nonpolar media. First-order kinetics with respect to monomer concentration was measured for selective cationic polymerization of IB in the mixed C 4 fraction feed at 230 C and the apparent rate constant for propagation was 0.028 min 21 .High polymerization temperature (T p ) or [FeCl 3 ] accelerate b-proton elimination or isomerizations and simultaneously decrease selectivity of b-proton abstraction from ACH 3 . Molecular weight decreased and molecular weight distribution (MWD) became narrow with increasing T p or [FeCl 3 ]. To the best of our knowledge, this is the first example to achieve high quality HRPIBs with near 100% of exo-olefin terminals and relatively narrow MWD (M w /M n 5 1.8) by a single-step process in nonpolar hydrocarbon media. PIBs with >70 mol % of exo-olefin end groups (ACH 2 AC(CH 3 )@CH 2 , structure A), preferably more than 80 mol %, are normally referred to as highly reactive polyisobutylenes (HRPIBs). HRPIBs, differing from those conventional PIBs with <10% of exo-olefin end groups, have found applications as intermediates in the preparation of additives for fuels and lubricants or other further functional modification since only terminal exo-olefin in PIB chain has a sufficiently high reactivity.3,4 HRPIBs can efficiently react with maleic anhydride by direct addition reaction to synthesize PIB/maleic anhydride adducts. The high content of exo-olefin end groups and relatively narrow molecular weight distributions (MWDs) are the most important quality criteria for HRPIBs.

The Li0.1B0.967PO4 Li+-conductive coating improves the cyclability and rate performance of Cr3+-doped LiNi0.5Mn1.5O4 high potential cathode.

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