Hydrothermal synthesis and electrochemical performance of Fe-doped Co hydroxide electrode materials

Journal of Solid State Electrochemistry - In order to meet the growing energy demand, it is of great significance to develop high-performance electrochemical energy storage materials. In this...     

Antimicrobial Activity of Pyrazinamide Coordination Frameworks Synthesized by Mechanochemistry

The urge for the development of a more efficient antibiotic crystalline forms led us to the disclosure of new antibiotic coordination frameworks of pyrazinamide, a well-known drug used for the treatment of tuberculosis, with some of the novel compounds unravelling improved antimycobacterial activity. Mechanochemistry was the preferred synthetic technique to yield novel compounds, allowing the reproduction of a 1D zinc framework, the synthesis of a novel hydrogen bonding manganese framework, and three new compounds with silver. The structural characterization of the novel forms is presented along with stability studies. The increased antimicrobial activity of the new silver-based frameworks against Escherichia coli, Staphylococcus aureus, and Mycobacterium smegmatis is particularly relevant.     

Schematic design of a complex thin-film luminescent screen usable for vacuum fluorescent and field emission display

Based on the facts related to solid-state cathodoluminescence, mixed excitation, and serial excitation recently discovered in our laboratory, a fundamental schematic design and a series of different schematic elaborated designs are proposed for protection from electron accumulation, reasonable use of a luminescent screen, and enhancement of light intensity.     

The electrochemical Peltier heats of Fe(CN) 6 3− /Fe(CN) 6 4− system at 295.15 K

A specially designed thermo-electrochemical calorimeter was applied to measure the electrochemical Peltier heats (EPH) of Fe(CN) ₆ ^3?/4? system at 295.15 K. The curves of the electrode potential changes and temperature changes against time for Fe(CN) ₆ ^3?/4? couple with five groups of different concentrations were obtained under the condition of various constant-current polarizations. The EPH values for the considered electrode reaction are determined to be ?41.31, ?42.73, ?44.28, ?45.87, and ?46.65 kJ mol^?1 at the respective concentrations of 0.125, 0.175, 0.225, 0.275, and 0.300 mol dm^?3; and the EPH and the apparent enthalpy change corresponding to the infinite dilution to be ?37.42 and ?84.10 kJ mol^?1 at 295.15 K, respectively.     

A Doping Technique that Suppresses Undesirable H2 Evolution Derived from Overall Water Splitting in the Highly Selective Photocatalytic Conversion of CO2 in and by Water

Photocatalytic conversion of CO₂ to reduction products, such as CO, HCOOH, HCHO, CH₃OH, and CH₄, is one of the most attractive propositions for producing green energy by artificial photosynthesis. Herein, we found that Ga₂O₃ photocatalysts exhibit high conversion of CO₂. Doping of Zn species into Ga₂O₃ suppresses the H₂ evolution derived from overall water splitting and, consequently, Zn‐doped, Ag‐modified Ga₂O₃ exhibits higher selectivity toward CO evolution than bare, Ag‐modified Ga₂O₃. We observed stoichiometric amounts of evolved O₂ together with CO. Mass spectrometry clarified that the carbon source of the evolved CO is not the residual carbon species on the photocatalyst surface, but the CO₂ introduced in the gas phase. Doping of the photocatalyst with Zn is expected to ease the adsorption of CO₂ on the catalyst surface.     

Exceedingly Fast Copper(II)‐Promoted ortho CH Trifluoromethylation of Arenes using TMSCF3

The direct ortho‐trifluoromethylation of arenes, including heteroarenes, with TMSCF₃ has been accomplished by a copper(II)‐promoted C? H activation reaction which completes within 30 minutes. Mechanistic investigations are consistent with the involvement of C? H activation, rather than a simple electrophilic aromatic substitution (S_EAr), as the key step.     

A new embedded 5(3) pair of modified Runge–Kutta–Nyström methods for the numerical solution of the Schrödinger equation

A new embedded 5(3) pair of modified Runge–Kutta–Nyström methods for the numerical solution of the Schrödinger equation is developed in this paper. The asymptotic expressions of the principal local truncation errors for large energies are obtained. We apply the new fifth-order method to the resonance problem, and apply the new embedded 5(3) pair to elastic scattering phase-shift problem. The numerical results show good numerical performance of the new embedded pair and the fifth-order method.     

Synthesis and self-assembly behavior of thermoresponsive poly(oligo(ethylene glycol) methyl ether methacrylate)-POSS with tunable lower critical solution temperature

This article reports on the synthesis of a novel amphiphilic polyhedral oligomeric silsesquioxane (POSS) end-capped poly(2-(2-methoxyethoxy)ethyl methacrylate)-co-oligo(ethylene glycol) methacrylate) (POSS-P(MEO₂MA-co-OEGMA)). These thermoresponsive organic–inorganic hybrid polymers exhibit critical phase transition temperature in water, which can be finely tuned by changing the feed ratio of OEGMA and MEO₂MA. The lower critical solution temperature (LCST) of POSS-P(MEO₂MA-co-OEGMA) increases from 31 to 59 °C with the increasing of OEGMA content. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) studies show that these polymers can self-assemble into spherical micelles with the thermosensitive block into the corona and the POSS forming the core, and larger aggregates are formed when the temperature values are above their LCSTs. These thermoresponsive polymers POSS-P(MEO₂MA-co-OEGMA) with self-assembly behavior and tunable tempetature-responsive property have the potential applications in material science and biotechnology.     

Facile Preparation of WO3−x Dots with Remarkably Low Toxicity and Uncompromised Activity as Co-reactants for Clinical Diagnosis by Electrochemiluminescence

The exceptional nature of WO_3−x dots has inspired widespread interest, but it is still a significant challenge to synthesize high-quality WO_3−x dots without using unstable reactants, expensive equipment, and complex synthetic processes. Herein, the synthesis of ligand-free WO_3−x dots is reported that are highly dispersible and rich in oxygen vacancies by a simple but straightforward exfoliation of bulk WS₂ and a mild follow-up chemical conversion. Surprisingly, the WO_3−x dots emerged as co-reactants for the electrochemiluminescence (ECL) of Ru(bpy)₃²⁺ with a comparable ECL efficiency to the well-known Ru(bpy)₃²⁺/tripropylamine (TPrA) system. Moreover, compared to TPrA, whose toxicity remains a critical issue of concern, the WO_3−x dots were ca. 300-fold less toxic. The potency of WO_3−x dots was further explored in the detection of circulating tumor cells (CTCs) with the most competitive limit of detection so far.