Charge–Discharge Performance of Copper Metal Positive Electrodes in Fluorohydrogenate Ionic Liquids for Fluoride-Shuttle Batteries

In search of room-temperature electrolytes for fluoride-shuttle batteries, fluorohydrogenate ionic liquids (FHILs) have emerged, showing high ionic conductivities and better operational practicality. To enhance the performance of these electrolytes, the charge–discharge behavior of copper metal as positive electrodes in FHILs was investigated in this study. In the [C₂C₁im][(FH)₂.₃F] (C₂C₁im = 1-ethyl-3-methylimidazolium) FHIL electrolyte, although the 1st discharge capacity of 599 mAh (g-Cu)⁻¹ included the reductive reaction of surface oxide films, the 2nd discharge capacity of 444 mAh (g-Cu)⁻¹ that corresponds to 53% of the theoretical capacity was achieved. However, the capacity declines to 167 mAh (g-Cu)⁻¹ at the 20th cycle, indicating low capacity retention. In contrast, the adoption of [C₂C₁pyrr][(FH)₂.₃F] (C₂C₁pyrr = N-ethyl-N-methylpyrrolidinium) electrolyte confers improved cycleability across the cycles with a higher discharge capacity of 210 mAh (g-Cu)⁻¹ at the 20th cycle. Scanning electron microscopy and energy-dispersive X-ray spectroscopy performed on the electrode surfaces confirm reduced electrode degradation characterized by suppressed aggregation of copper particles in [C₂C₁pyrr][(FH)₂.₃F] due to its low CuF₂ solubility compared with [C₂C₁im][(FH)₂.₃F]. Herein, we demonstrate the use of FHILs with low CuF₂ solubilities as a strategy for improving the charge–discharge performance of copper metal positive electrodes in fluoride-shuttle batteries

Deoxofluorination of Activated Carbon Electrode with Sulfur Tetrafluoride for Electric Double Layer Capacitor

Electric double layer capacitors are energy storage devices with advantages of fast charge-discharge and long life span. Surface modification of activated carbon electrodes is an effective way to improve their performance. For this purpose, deoxofluorination of activated carbon with sulfur tetrafluoride was attempted in this study. Successful introduction of fluorine atom on the surface of activated carbon resulted in the increased capacitance and improved coulombic efficiencies in electrochemical tests for electric double layer capacitors

Deoxofluorination of graphite oxide with sulfur tetrafluoride

In this study, deoxofluorination of graphite oxide (GO) using sulfur tetrafluoride (SF₄) at a temperature below the decomposition temperature of GO (∼200 °C) was investigated for the first time with and without HF catalysis. At 25 °C, the reaction proceeds only at high SF₄ pressures (≥8 atm) when not catalyzed by HF and at 1 atm SF₄ under the catalysis of HF. The degree of fluorination increases at higher temperatures and SF₄ pressures. Hydroxy and carbonyl groups are replaced by fluorine following this reaction, and SF₄ and SOF₂ are introduced into the product, while the epoxy groups do not react. SF₄ and SOF₂ in the products are removed by washing with water. The obtained product is less hygroscopic than pristine GO owing to the hydrophobicity of the fluorine atom. The interlayer separation of the product is increased after deoxofluorination despite the smaller size of fluorine than the sizes of the oxygen-containing functional groups. When compared with direct fluorination using elemental fluorine, deoxofluorination using SF₄ has the advantages of high reactivity with hydroxy groups and the preservation of the carbon skeleton, and the reaction results in the formation of graphite oxyfluoride

Discharge Characteristic of Fluorinated Graphene-like Graphite as a Cathode of Lithium Primary Battery

The 64th special issue "Frontiers of Carbon Materials"Graphene-like graphite prepared by heating graphite oxide under vacuum at 800 degrees C was fluorinated by elemental fluorine in the presence of HF at room temperature. The interlayer spacing of the resulting material was 0.639 nm and it showed CxF type characteristics. The fluorine content of it (x = 1.7) was higher than that obtained from natural graphite (x = 2.3). The discharge capacity of it as a cathode of lithium primary battery reached 940 mAhg(-1) at a low current density, which was 50% larger than the theoretical capacity based on the 100% discharge of fluorine

Potassium single cation ionic liquid electrolyte for potassium-ion batteries

Potassium-ion batteries (PIBs) are a promising post-lithium-ion battery (LIB), as their resources are abundant and low-cost and may have a higher voltage than LIBs. However, the high operating voltage and extremely high reactivity of potassium metal require a chemically safe electrolyte with oxidative and reductive stabilities. In this study, a potassium single cation ionic liquid (K-SCIL), which contains only K⁺ as the cationic species and has a high electrochemical stability, low flammability, and low vapor pressure, is developed as an electrolyte for PIBs. The mixture of potassium bis(fluorosulfonyl)amide and potassium (fluorosulfonyl)(trifluoromethylsulfonyl)amide at a molar ratio of 55:45 had the lowest melting point of 67 °C. The K⁺ concentration in this K-SCIL is high (8.5 mol dm⁻³ at 90 °C) due to the absence of solvents and bulky organic cations. In addition, the electrochemical window is as wide as 5.6 V, which enables the construction of PIBs with a high energy density. A high current density can be achieved with this K-SCIL, owing to the absence of a K⁺ concentration gradient. The electrolyte was successfully used with a graphite negative electrode, enabling the reversible intercalation/deintercalation of K⁺, as confirmed by X-ray diffraction

握力は、糖尿病患者の心血管イベントの独立した予測因子である

Diabetes mellitus (DM) is associated with an increased incidence of cardiovascular events and an elevated prevalence of sarcopenia. However, the relationship between cardiovascular events and sarcopenia in patients with DM remains unclear. This study examined this relationship and investigated the predictors of cardiovascular events in this population.This study enrolled 161 patients with DM and no history of cardiovascular diseases who were admitted to our hospital for the treatment of DM between September 2012 and December 2015. Patients were divided into sarcopenia and non-sarcopenia groups, and were followed until March 2019. The primary endpoint was major adverse cardiovascular events (MACE).The mean age was 65.9 ± 1.8 years old and the mean follow-up period was 4.1 ± 0.8 years. The log-rank test indicated that MACE differed significantly between the two groups (P < 0.0001). Multivariate Cox hazard analysis identified the cardio-ankle vascular index (CAVI) and handgrip strength as independent predictors of MACE (hazard ratio [HR] = 1.18, P = 0.039; and HR = 0.70, P = 0.016, respectively).Handgrip strength is an indicator of sarcopenia in diabetic patients, and together with CAVI it was independently associated with the incidence of MACE. This suggests that the handgrip strength test might be useful in the management of patients with DM at high risk of cardiovascular outcomes.博士（医学）・乙第1493号・令和3年3月15日© 2021 by the International Heart Journal Association発行元であるインターナショナル・ハート・ジャーナル刊行会の許諾を得て登録（2021年6月23日付）ジャーナル公式サイト（J-STAGE内）：https://doi.org/10.1536/ihj.20-67

ジヘイセイ ショウガイ ガ アル コドモ ノ キョウドウ チュウイ コウドウ ニ エイキョウ スル エンジョシャ ノ コウドウ : ゲンゴテキ エンジョ ト ヒゲンゴテキ エンジョ ノ ヒカク

It is said that the infantile autism have a disability of joint attention in social behavior. This study is aimed at comparing the effectiveness of verbal communication support and non-verbal communication support，which raises joint attention behavior of infantile autism. In the investigation we use alternating treatment design. Subjects were two infants. Both were diagnosed autism. Based on Scaffolding， support behavior was divided into verbal communication support and non-verbal communication support. When they played at housekeeping，we analyzed which support produced a greater number of joint attention behavior. The result showed that in one of them the verbal communication support was more effective than non-verbalcommunication support in joint attention producing. It suggests that he developed the ability of verbal sensitivity. Another result was not statistically significant as both subjects，when they had verbal communication support， showed a trend of more joint attention behavior as the supporter's behavior was lesser. There was a discussion about this result

Improvement of Electrochemical Stability Using the Eutectic Composition of a Ternary Molten Salt System for Highly Concentrated Electrolytes for Na-Ion Batteries

The increase in the concentration of electrolytes for secondary batteries has significant advantages in terms of physicochemical and electrochemical performance. This study aims to explore a highly concentrated electrolyte for Na-ion batteries using a ternary salt system. The eutectic composition of the Na[N(SO₂F₂]–Na[N(SO₂F)(SO₂CF₃)]–Na[SO₃CF₃] ternary molten salt system increases solubility into an organic solvent, enabling the use of highly concentrated electrolytes for Na-ion batteries. The ternary salt system achieved concentrations of 5.0 m (m = mol kg⁻¹) with propylene carbonate (PC), 2.9 m with dimethoxyethane, 2.0 m with ethylene carbonate/dimethyl carbonate, and 3.9 m with ethylene carbonate/diethyl carbonate. The highly concentrated electrolyte of 5.0 m in PC suppressed Al corrosion and exhibited better oxidative stability. Stable electrochemical performance using hard carbon/NaCrO₂ in the full-cell configuration introduces a new strategy to explore highly concentrated electrolytes for secondary batteries

Structural Basis of the Highly Efficient Trapping of the HIV Tat Protein by an RNA Aptamer

AbstractAn RNA aptamer containing two binding sites exhibits extremely high affinity to the HIV Tat protein. We have determined the structure of the aptamer complexed with two argininamide molecules. Two adjacent U:A:U base triples were formed, which widens the major groove to make space for the two argininamide molecules. The argininamide molecules bind to the G bases through hydrogen bonds. The binding is stabilized through stacking interactions. The structure of the aptamer complexed with a Tat-derived arginine-rich peptide was also characterized. It was suggested that the aptamer structure is similar for both complexes and that the aptamer interacts with two different arginine residues of the peptide simultaneously at the two binding sites, which could explain the high affinity to Tat

Relationship between lymph node metastasis and E-cadherin expression in submucosal invasive gastric carcinomas with gastric-phenotype

Background : Recent advances in immunohistochemical staining have led to the proposition of a classification of gastric carcinomas based on cellular phenotypes, and the degree of biological malignancy of gastric-phenotype carcinomas has attracted particular attention. Subjects and Methods : One hundred and seven submucosal (SM) invasive carcinomas encountered in our center were examined for their histological type, cellular phenotype, and E-cadherin expression status to clarify their relationships with lymph node metastasis. Results : Eleven (10.3%) of 107 SM gastric carcinomas were lymph node metastasis-positive. Gastric-phenotype carcinomas accounted for 20.6%, with a lymph node metastasis rate of 27.3% (6/22), which was significantly higher (p<0.05) than those of intestinal-phenotype carcinomas (5.9%) and mixed-phenotype carcinomas (2.9%). In terms of E-cadherin expression, only carcinomas with reduced E-cadherin expression showed lymph node metastasis at a rate significantly higher than that of carcinomas with normal E-cadherin expression (p<0.05). The lymph node metastasis rate (46.2%) of gastric-phenotype carcinomas with reduced E-cadherin expression was significantly higher than those of carcinomas of other phenotypes (p<0.05). Conclusion : Since gastric-phenotype differentiated carcinomas with reduced E-cadherin expression have the potential for becoming undifferentiated, the risk of lymph node metastasis should be considered