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Eriobotrya japonica leaf is included in the Chinese Pharmacopoeia, and is widely used as a medicinal material in traditional medicine. The present study investigated the potential genotoxic effects of E. japonica leaf extract (EJE) using three standard battery systems. Genotoxicity tests were conducted following the test guidelines of the Organisation for Economic Cooperation and Development (OECD) and Ministry of Food and Drug Safety (MFDS), with application of Good Laboratory Practice. The bacterial reverse mutation test was conducted using the pre-incubation method in the presence or absence of the metabolic activation system (S9 mixture). The in vitro chromosome aberration test was performed using cultured Chinese hamster lung cell line in the presence or absence of the S9 mixture. The in vivo micronucleus test was performed using ICR mice. The bacterial reverse mutation test with Salmonella typhimurium strains TA98, TA100, TA1535, and TA1537 and Escherichia coli strain WP2uvrA showed that EJE did not induce gene mutations at any dose level in all the strains tested. EJE also did not show any chromosomal aberrations in the in vitro chromosomal aberration test and in the in vivo micronucleus test. These results showed that EJE did not induce mutagenicity or clastogenicity in either in vitro or in vivo systems.

Due to success of desired doping, ion implantation has been widely used for semiconductor processing. In this work, we used nitrogen ion implantation to enhance magnetism in CeFe12 epitaxial thin films. To optimize nitrogen contents in CeFe12 and minimize the damage caused by the high-energy ion beam, we varied the thickness of the capping Mo layer. The saturation magnetization increased nearly 25% by nitrogen ion implantation into CeFe12 thin film. This phenomenon is explained by density functional theory calculations and confirmed by the magnetic resonance technique. The ion implantation and design strategy can be used for light-ion implantation into lattices to modulate magnetic, optical, and electrical properties.

The cycling and storage performances of LiCoO 2 (LCO)-LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM)/pitch-coated silicon alloy-graphite (Si-C) full cells with ethylene carbonate (EC)–based and fluoroethylene carbonate (FEC)–based electrolytes are investigated at elevated temperatures. Excess FEC (used as a co-solvent in LiPF 6 -based electrolytes), which is not completely consumed during the formation of the solid electrolyte interphase (SEI) layer on the electrodes, is prone to defluorination in the presence of Lewis acids such as PF 5 ; this reaction can generate unwanted HF and various acids (H 3 OPF 6 , HPO 2 F 2 , H 2 PO 3 F, H 3 PO 4 ) at elevated temperatures. Our investigation reveals that the HF and acid compounds that are formed by FEC decomposition causes significant dissolution of transition metal ions (from the LCO-NCM cathode) into the electrolyte at elevated temperatures; as a result, the reversible capacity of the full cells reduces because of the deposition of the dissolved metal ions onto the anode. Moreover, we demonstrate possible mechanisms that account for the thermal instability of FEC in LiPF 6 -based electrolytes at elevated temperatures using model experiments.

Lithium difluoro(oxalato)borate (LiFOB) is investigated as an additive for enhancing the electrochemical performance of high-voltage lithium cobalt oxide (LiCoO2, LCO)/lithium nickel manganese cobalt oxide (LiNi0.6Co0.2Mn0.2O2, NMC) cathodes and high-capacity silicon/graphite (Si-C) anodes. LCO-NMC/Si-C full cells with a LiFOB additive have been found to exhibit improved high temperature electrochemical performance. To confirm the effects of LiFOB on the cathode and the anode, the surface chemistry of the anodes and cathodes cycled in electrolytes with and without the LiFOB additive are examined using ex-situ X-ray photoelectron spectroscopy (XPS). The LiFOB additive produces a LiF-based solid electrolyte interphase (SEI) on the Si-C anode and a carboxylate-based SEI on the LCO-NMC cathode.

Crosslinked (C-ESFx-BP) and non-crosslinked (N-ESFx-BP) sulfonated poly(arylene ether) (SPAE) membranes containing high fluorine contents were prepared as a function of the degree of sulfonation (DS) and evaluated for use as a highly potential chlorine-resistant reverse osmosis (RO) membrane. C-ESFx-BP membranes were obtained by covalent crosslinking among ethynyl end groups of the polymer chains via thermal curing. Both C-ESFx-BP and N-ESFx-BP membranes show the increase in NaCl rejection with decreasing DS, while water permeability declines due to the decrease of hydrophilicity. In particular, C-ESF70-BP membrane showed excellent salt (NaCl) rejection up to 98.4% compared with that of N-ESF70-BP membrane of 90.3% but showed slightly lower water permeability of 0.6 L μm/m2 h bar than that of 0.8 L μm/m2 h bar for N-ESF70-BP. Moreover, these C-ESFx-BP and N-ESFx-BP membranes displayed the long-term stability longer than 30 days during the operation condition under high acidic chlorine concentration of NaOCl 4000 ppm unlike commercial PA membranes which are unstable under the chlorine treatment. The stability comparison between them were observed by ATR-IR, retention ratio of molecular weight (RRMW), contact angle and X-ray photoelectron spectroscopy (XPS).

This paper demonstrates the optimization of proton conductivity and water uptake for cross-linkable polymer electrolytes through synthesis and characterization of end-group cross-linkable sulfonated poly(arylene ether) copolymers. The extent of reaction of cross-linking was controlled by reaction time resulting in a series of polymers with two, independent tunable parameters, degree of sulfonation (DS) and degree of cross-linking (DC). For the polymers presented, cross-linking improved proton conductivity while reducing water uptake, an uncommon trend in polymer electrolytes where water is critical for proton conduction. Other trends relating to changes are reported and the results yield insight into the role of DS and DC and how to optimize electrochemical properties and performance of polymer electrolytes through these tunable parameters. Select polymer electrolytes were tested in fuel cells where performance and durability with accelerated relative humidity cycling were compared with Nafion ® .

Crosslinkable sulfonated poly(arylene ether ketone) copolymers with various degrees of sulfonation (DS) were prepared and evaluated for use as proton exchange membranes (PEM). The copolymers were synthesized via step growth polymerization using 2,8-dihydroxynaphthalene-6-sulfonated salt (2,8-DHNS-6), 4,4′-(hexafluoroisopropylidene) diphenol (6F-BPA), 4,4′-biphenol (BP), and 4,4′-difluorobenzophenone (DFBP). 1 H NMR and FTIR-ATR spectra confirmed the structure of the copolymers and were also used to determine the obtained DS values of the copolymers. Crosslinked membranes were obtained by thermal curing of the crosslinkable copolymers. The membranes formed a crosslinking network structure via covalent bonding. The glass transition temperatures ( T g ) of the crosslinked membranes were determined by differential scanning calorimetry (DSC) and ranged from 208 to 258 °C. The decomposition temperatures ( T d ) of the membranes ranged from 309 to 325 °C for acid forms. The resulting membranes were characterized via an evaluation of their essential membrane properties, such as ion exchange capacity (IEC), water uptake, and proton conductivity. The performance of the membranes was found to be dependent on the DS and IEC.

As a novel class of proton exchange membrane (PEM) materials for application in fuel cells, sulfonated poly(arylene ether ketone)s (SPAEK-BPs) were prepared by polycondensation via a nucleophilic substitution reaction followed by post-sulfonation. In this way, SPAEK-BPs with different degrees of sulfonation (DS) were quantitatively synthesized via the use of chlorosulfonic acid as the sulfonating agent. It was discovered that only one sulfonic acid group can be selectively introduced without degradation per each repeating unit of polymer due to requirements for controlling reaction conditions such as reaction time and temperature. In this study, the experimentally observed DS were close to the theoretical values expected from the monomer ratios. The glass transition temperatures ( T g 's) and decomposition temperatures ( T d 's) of the polymers varied from 167 to 213 and 298 to 343 °C, respectively. In addition, the proton conductivities of the SPAEK-BP membranes exhibited up to a maximum of about 0.083 S/cm at 25 °C and 0.098 S/cm at 80 °C.