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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 difluorophosphate (LiDFP) as a reducible additive is employed to overcome the unsatisfactory rate capability and cycling instability of highly pressed graphite electrodes with high mass loading (8.1 mg/cm2) with a vinylene carbonate (VC)-derived surface film that hampers the charge transport at the graphite–electrolyte interface at high rates. Our investigation reveals that LiDFP modifies the surface chemistry induced by VC and makes a more ionically conductive surface film on graphite, ensuring good rate capability. Keywords: Lithium–ion battery, Graphite, Anode, Electrolyte, Additive

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.

The cross-linkable copolymers (SHQx-TFVys) with varying degrees of sulfonation (DS) from 70 to 95% were prepared from potassium-2,5-dihydroxybenzenesulfonate (SHQ), decafluorobiphenyl (DFBP), and 4-(trifluorovinyloxy)-biphenyl-2,5-diol (TFVOH) as a cross-linkable moiety. To develop a highly stable polymer electrolyte membrane (PEM) for application in polymer electrolyte fuel cells (PEFC)s, cross-linked membranes were prepared by chemical cross-linking. The cross-linked membranes were synthesized by varying the amount of TFVOH (5–30 mol %) in order to achieve desirable PEM properties. The structures of the cross-linkable monomer and polymers were investigated by 1H and 19F NMR and FT-IR spectra. The cross-linked membranes exhibited good glass transition temperature and thermal stability up to 239–271 °C and 290–312 °C, respectively. The crosslinked membranes (DS range 80–95%) exhibited higher proton conductivity(0.098–0.151 S/cm) than Nafion 212 (0.092 S/cm). Moreover, all membranes possessed lower methano...

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).

New series of ethynyl-terminated sulfonated-fluorinated poly(arylene ether)s (ESF-6Fs) were synthesized via nucleophilic aromatic substitution reaction (SNAr) from potassium 2,5-dihydroxybenzenesulfonate (SHQ), 4,4′-(hexafluoroisopropylidene)diphenol (6FBPA), and decafluorobiphenyl (DFBP), followed by the reaction with 3-ethynylphenol. The cross-linked ESF-6F membranes exhibited high glass-transition temperatures in the range of 258−276 °C and good thermal degradation temperatures in the range of 308−328 °C. To optimize the proton conductivity and water uptake of the cross-linked ESF-6F membranes, various volume-related parameters (length-scaled parameters) were introduced. Using those parameters, the proton conductivity and water uptake of the cross-linked ESF-6F membranes were compared with sulfonated poly(arylene ether sulfone) random copolymer (BPSH), Nafion membrane, and another cross-linked membrane. In addition, the proton conductivity of optimized ESF-6F membrane was observed as a function of rela...

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 ® .

Side chain crosslinked (C-SFPEx-CMy) sulfonated poly(arylene ether) (SPAE) membranes containing fluorine moiety with varying degree of sulfonation (DS) were prepared and evaluated for use as a thin-film composite membrane for seawater desalination. C-SFPEx-CMy membranes were obtained by covalent crosslinking among ethynyl groups at the polymer side chain through thermal curing. The crosslinked network structure suppressed the water uptake and swelling ratio. A novel type of composite membranes (TC-SFPEx-CMy) were prepared side chain crosslinked SPAE layer containing fluorine moiety on top of PET non-woven with epoxy resin as bonding agent. TC-SFPEx-CMy show the increase in NaCl rejection as DS decreases from 30% to 70%. NaCl rejection of the membranes increased with increasing corsslinking moiety (CM) while water permeability decreases due to the crosslinked net work structure. Particularly, crosslinked membrane of 30 mol % of CM could enhance the salt (NaCl) rejection property up to 85.3 % as compared to...

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.

End-group cross-linkable sulfonated poly(arylene ether) polymer (E-SFQK) was synthesized via direct polymerization of potassium 2,5-dihydroxybenzenesulfonate (SHQ) and decafluorobiphenyl (DFBP), followed by a reaction with ethynylphenol (EP). The cross-linking reaction of the ethynyl end group of E-SFQK was performed at 250 °C. After cross-linking, proton conductivity, water uptake, and swelling ratio of cross-linked membrane decreased from 0.16 (noncross-linked membrane) to 0.13 S/cm, from 86% to 42%, and from 31% to 13%, respectively. The effect of cross-linking time on proton conductivity, water uptake, and swelling ratio were also investigated. Methanol permeability of cross-linked membrane was compared with Nafion 117 due to solubility of noncross-linked membranes in methanol. The cross-linked membrane performed better, with a methanol permeability of 88 × 10−8 cm2/s, as compared with 154 × 10−8 cm2/s for Nafion 117. The cross-linked membrane also exhibited improved chemical resistance and oxidative ...

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.