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The performance of the graphite anode of lithium-ion batteries is greatly affected by the solid electrolyte interphase (SEI) generated at the first charge. However, there are few studies on the kinetics of the lithium-ion intercalation/de-intercalation reaction in graphite to investigate the effect of SEI. In this study, the correlation between the interfacial lithium-ion transfer resistance (Rct) and the double layer capacitance (Cdl) of graphite composite electrodes coated with various SEIs was investigated. It was found that the value of 1/RctCdl was different for each SEI, that is, the frequency (or rate) of intercalation and de-intercalation of lithium ions into graphite was different for each SEI. The activation energy of Rct was almost the same for all the electrolyte solutions. These results indicate that the pre-exponential factor of the Arrhenius equation governing the rate of interfacial ion transfer in a practical graphite anode is dependent on the nature of SEI.

BACKGROUND Early multiple-drug therapy for severe childhood immunoglobulin A (IgA) nephropathy prevents the progression of nephritis and improves the long-term prognosis. Recent studies have focused on the relationship between the pathophysiology of IgA nephropathy and tonsillar focal infection, and the efficacy of tonsillectomy with methylprednisolone pulse therapy in children has been demonstrated. However, no study has reported on the relationship between the period from diagnosis to tonsillectomy and the long-term prognosis of IgA nephropathy. METHODS To clarify the long-term effects of an early tonsillectomy, 40 patients who were diagnosed with severe IgA nephropathy in childhood and underwent a tonsillectomy were divided into two groups based on the period from diagnosis to undergoing tonsillectomy: Group A, less than 3 years; and Group B, more than 3 years. The primary endpoint of this study was the change in the amount of proteinuria. Renal prognosis was evaluated 10 years after the diagnosis. RESULTS This study enrolled 40 patients diagnosed with severe IgA nephropathy in childhood who underwent tonsillectomy after multiple-drug therapy with/without methylprednisolone pulse therapy at Kindai University Hospital; eight patients were excluded based on the exclusion criteria. Group A consisted of 18 patients and Group B, 14 patients. Proteinuria and hematuria levels were significantly reduced in the early surgery group (P < 0.01). No significant differences were found in serum creatinine, uric acid, and IgA/C3 ratio. CONCLUSIONS High proteinuria levels worsen the renal prognosis in IgA nephropathy. Tonsillectomy in less than 3 years combined with multiple-drug therapy after the initial diagnosis could improve long-term prognosis.

Electrocatalysts with high activity for the oxygen evolution reaction (OER) play a pivotal role in various electrochemical devices such as water electrolyzers and metal–air batteries. Electronic in...

In electrochemical reactions involving protons or hydroxide ions, local pH in the vicinity of a working electrode dynamically changes. In this study, we introduce the measurements of the local pH i...

This study attempted to stabilize the nanosurface of LiNiO

Here, highly concentrated sodium bis(fluorosulfonyl)amide (NaFSA) aqueous electrolytes were examined for the aqueous electrolytes of electric double-layer capacitors with wide potential window. Firstly, fundamental properties of electrolytes were investigated using conductivity measurements and Raman spectroscopy. During cyclic voltammetry of activated carbon electrodes, aluminum corrosion was observed for positive electrode side. After current collectors of positive electrodes were changed to titanium, capacitor reactions were confirmed for both of positive electrode and negative electrode sides in NaFSA aqueous electrolytes. In addition, resistances of activated carbon electrodes in NaFSA aqueous electrolytes were smaller than those in LiTFSA aqueous electrolytes.

While micronuclei (MN) store extranuclear DNA and cause genome instability, the effects of nuclear envelope (NE) assembly defects associated with MN on genome instability remain largely unknown. Here, we investigated the NE protein distribution in MN using HeLa human cervical cancer cells. Under the standard condition and two pharmacological culture conditions, we found that three types of NE protein assemblies were associated with MN: 1) intact NE assembly, in which both core and non-core NE proteins were evenly present; 2) type I assembly, in which only core NE proteins were detectable; and 3) type II assembly in which a region deficient for both core and non-core NE proteins existed and a pattern recognition receptor, cyclic guanosine monophos-phate-adenosine monophosphate synthase, was frequently detected. Our findings provide experimental settings and a method of grouping MN-associated NE defects, which may be helpful for researchers who are interested in regulation of genome and nuclear organization relevant to cancer development.

Solid electrolyte interphase (SEI) on a graphite-negative electrode plays an important role in lithium-ion batteries. The roles of the SEI involve a passivation of a solvent co-intercalation reaction, but why the SEI can suppress the solvent co-intercalation reaction is not fully understood. In this study, the solvent co-intercalation behavior against various SEI-covered graphite electrodes was investigated using cyclic voltammetry and in situ Raman spectroscopy. Ethylene carbonate (EC)-treated, vinylene carbonate (VC)-treated, and untreated graphite electrodes were compared in a dimethoxyethane (DME)-based electrolyte solution. Whereas the DME co-intercalation constantly proceeded from 1.2 to 0.6 V versus Li/Li+ for the untreated graphite electrode, the co-intercalation was relatively suppressed above 0.8 V versus Li/Li+ for the EC-treated and VC-treated graphite electrodes. Below 0.7 V versus Li/Li+, the VC-treated electrode exhibited higher passivation ability than the EC-treated one. In addition, the co-intercalation behavior in electrolyte solutions containing an SEI-reagent in advance was also investigated. In this case, the passivation ability was further improved.

Graphite intercalation compounds of bis(fluorosulfonyl)amide (FSA-GICs) are electrochemically synthesized in a highly concentrated aqueous solution. While only water decomposition occurs at the graphite electrode in a dilute aqueous solution (1 mol kg−1 NaFSA), redox peaks clearly appear in a highly concentrated aqueous solution (19 mol kg−1 NaFSA). Under the application of a constant current, the electrode potential reaches 1.7 V (vs. Ag/AgCl), which is far beyond the upper limit of the potential window, in 19 mol kg−1 NaFSA aq., and the formation of FSA-GIC is confirmed by X-ray diffraction patterns. Acceptor-type GICs using organic anions are observed for the first time in highly concentrated aqueous solutions of NaFSA. Keywords: Concentrated aqueous solutions, Graphite intercalation compounds, Water decomposition, Potential window

Electrochemistry deals with the interrelationship between electrical and chemical energy. Various potentials appear in electrochemistry and pertain to one another in practical cells. Understanding the electrode potential is an important step in acquiring basic knowledge of electrochemistry and extending it to specific applications. This comprehensive paper outlines the fundamentals and related subjects of electrode potentials, including electrochemical cells and liquid junction potentials. Aqueous solution systems are ideal for connecting the theoretical background of electrode potentials to practical electrochemical measurements. Accordingly, the basic electrode chemistry in aqueous systems is described in this paper, as well as several advanced concepts introduced in recent studies.

Hydrodynamics has received considerable attention for application in improving microbial fuel cell (MFC) performance. In this study, a method is proposed to calculate the effect of fluid flow on MFC current production from sewage wastewater. First, the effect of flow velocity in an up-flow channel was evaluated, where an air-core MFC was polarized with external resistance (Rext). When tested at a flow velocity ranging from 0 to 20 cm s−1, the MFC with the higher flow velocity produced more current. In sewage wastewater with a chemical oxygen demand (COD) of 76 mg L−1, the MFC polarized with 3 Ω of Rext, and a flow velocity of 20 cm s−1 had 5.4 times more current than the MFC operating in a no-flow environment. This magnitude decreased with higher Rext and COD values. The Michaelis–Menten equation, modified herein by integrating COD and flow velocity, demonstrated the production of current by MFC operating under different conditions of flow. Calculation of current by MFC in a virtual fluid suggested that the flow surrounding the MFC varied with the configuration and affected the current production.

Conversion/alloy active materials, such as ZnO, are one of the most promising candidates to replace graphite anodes in lithium-ion batteries. Besides a high specific capacity (qZnO = 987 mAh g-1), ZnO offers a high lithium-ion diffusion and fast reaction kinetics, leading to a high-rate capability, which is required for the intended fast charging of battery electric vehicles. However, lithium-ion storage in ZnO is accompanied by the formation of lithium-rich solid electrolyte interphase (SEI) layers, immense volume expansion, and a large voltage hysteresis. Nonetheless, ZnO is appealing as an anode material for lithium-ion batteries and is investigated intensively. Surprisingly, the conclusions reported on the reaction mechanism are contradictory and the formation and composition of the SEI are addressed in only a few works. In this work, we investigate lithiation, delithiation, and SEI formation with ZnO in ether-based electrolytes for the first time reported in the literature. The combination of operando and ex situ experiments (cyclic voltammetry, X-ray photoelectron spectroscopy, X-ray diffraction, coupled gas chromatography and mass spectrometry, differential electrochemical mass spectrometry, and scanning electron microscopy) clarifies the misunderstanding of the reaction mechanism. We evidence that the conversion and alloy reaction take place simultaneously inside the bulk of the electrode. Furthermore, we show that a two-layered SEI is formed on the surface. The SEI is decomposed reversibly upon cycling. In the end, we address the issue of the volume expansion and associated capacity fading by incorporating ZnO into a mesoporous carbon network. This approach reduces the capacity fading and yields cells with a specific capacity of above 500 mAh g-1 after 150 cycles.

This study investigated the fundamental mechanisms of the loss of capacity of LiNiO

Electrically rechargeable zinc oxygen batteries are promising energy storage devices. They appeal due to the abundance of zinc metal and their high energy density. Research on zinc oxygen batteries is currently focusing on the development of electrode materials. Since the progress is rapid and no state-of-the-art is agreed upon yet, it is difficult to benchmark their performance. This circumstance also complicates the use of the generated electrochemical data for model-based research – simulating the processes in the battery requires reliable performance data and material properties from experimental investigations. Herein we describe reproducible data on the cycling performance and durability of zinc oxygen batteries. We utilize anodes and gas diffusion electrodes (with the bifunctional catalysts Sr2CoO3Cl, Ru-Sn oxide, and Fe0.1Ni0.9Co2O4 with activated carbon) with low degradation during cycling, and present voltage data of current-dependent discharge and charge. All in all, we stimulate to reuse the data for parameter fitting in model-based work, and also to evaluate novel battery materials by preventing or minimizing side reactions with the testing protocol and setup utilized., Measurement(s) battery cycling performance • Voltage • Electrical Current • cycling stability Technology Type(s) galvanostat • electrochemical analysis Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.13066070

Background The association of hypertension with congenital renal hypoplasia has been established. We report a case of an infant who underwent nephrectomy for hypertension. Case presentation Magnetic resonance imaging for the mother revealed fetal renal masses, and fetal multicystic dysplastic kidney was suspected. Following birth, the baby developed hypertension. Numerous investigations revealed that the left kidney was non-functional, and she was initiated on benazepril hydrochloride. However, because the drug response was poor, the left kidney was removed at the age of 7 months. Examination of the renal specimen revealed abrupt transition from normal to atrophic cortex with lobar atrophy and cysts. Tubular atrophy, marked abnormal blood vessels with wall thickening, gathered immature glomeruli, and parenchymal destruction were observed. Renin was partially localized in the proximal tubules and the parietal epithelium of the Bowman’s capsule in the immature glomeruli. We speculated that an abnormal vascular structure and irregular renin localizations may be the cause of hypertension. Serum renin and aldosterone levels gradually reduced post-surgery, reaching normal levels on the 90th postoperative day. A long follow-up is needed due to the possibility of the child developing hypertension in the future. Conclusion This is a case of an infant with MCDK, which discusses the clinicopathological features based on the pathophysiological analysis, including renin evaluation.

Background: Hyperlipidemia is an important characteristic feature of idiopathic nephrotic syndrome (NS) in children. This study was conducted to examine the lipid profiles, including small dense low-density lipoprotein (sdLDL-C), in childhood-onset NS.Methods: This retrospective study enrolled patients diagnosed with initial-onset NS in childhood and adolescence. Study parameters included lipid profiles. The “alternative LDL window” comprises the number and sizes of LDL particles estimated according to non-HDL-C and TG levels.Results: A total of 39 patients were enrolled who exhibited markedly increased lipid abnormalities, including TC, TG, LDL-C, and non-HDL-C levels (TC, 409.7 TC, TG, and sizes of LDL particles estimated as non-HDL-C, 332.3). Of the 39 patients, 32 (82%) were categorized in the area of hyper-TG/-non-HDL levels, which is considered as sdLDL. A positive correlation was found between non-HDL-C and TC (r = 0.96, P < 0.001), TG (r = 0.38, P = 0.018), LDL-C (r = 0.84, P < 0.001), TC/HDL (r = 0.53, P < 0.001), and atherogenic index of plasma (r = 0.42, P = 0.008).Conclusions: Our study demonstrated markedly increased lipid profiles during the acute phase of NS. Evaluation of lipid profiles using the “alternative LDL window” may help understand the state of hyperlipidemia in NS.

Sodium-ion batteries cannot employ graphite which is a typical negative electrode material for lithium-ion batteries. This is principally because sodium-ion cannot intercalate deeply into graphite, which has been a mystery for many years. Here, the mechanism of electrochemical sodium-ion intercalation into graphitic materials was investigated by using Raman spectroscopy and X-ray diffraction measurement to solve the question. Low stage sodium graphite intercalation compound (Na-GIC) was formed electrochemically only near the surface of graphite by potential holding above the sodium metal deposition potential. On the other hand, the high stage Na-GIC was formed electrochemically in the bulk at the sodium metal deposition potential. In addition, the apparent diffusion distance and the apparent diffusion coefficient of sodium-ion inside graphite were calculated using chronopotentiograms and potentiostatic intermittent titration technique. As a result, the sodium-ion diffusion inside spherical graphite was not slow enough to explain the limited reactivity. Hence, the limitation of sodium-ion intercalation into graphite might be originated from not the kinetic limitation inside graphite but the thermodynamic limitation.

Invited for this month's cover are the groups of Shih-kang Lin at the National Cheng Kung University and Takeshi Abe at Kyoto University. The image shows how interfacial chemistry design can play a role in unlocking higher-energy-density and fast-charging Li

Electrically rechargeable zinc-oxygen batteries are promising for sustainable and resource-uncritical energy storage with high energy density. Their commercialization is hindered by the limited cycling stability – especially due to the zinc anode. In this study, we present a zinc anode that stands out with two advantages: The use of an energy-saving and low temperature preparation method, and the mechanical stabilization of the pore system with a lightweight anion-exchange ionomer. Our approach increases cycling stability for both the zinc-nickel oxide hydroxide cell and the zinc-oxygen cell: Electrochemical analysis in combination with operando X-ray diffraction measurements prove that the novel zinc anode is electrically rechargeable and can be cycled up to five times more often than zinc sponge anodes without anion-exchange ionomer to a depth of discharge of 35%. Scanning electron microscopy is used to evidence that the anion-exchange ionomer stabilises the entire pore system during cycling. We furthermore analyse zinc-oxygen batteries with anion-exchange ionomer at all parts – inside the zinc sponge anode, as separator and at the cathode. These cells can be electrically recharged with unprecedented high utilization of active material, and thus highlight the benefit of introducing an ion-selective coating into alkaline batteries with zinc anode.

Dimethyl sulfoxide (DMSO) is electrochemically co-intercalated with lithium ions into graphite to form a stable ternary graphite-intercalation-compound (GIC), Li-DMSO-GIC. To elucidate the details of the co-intercalation behavior, in situ Raman spectroscopy was performed to observe the structural variations in graphite during the potential scan. During the scan from 2.44 to 1.00 V, DMSO was co-intercalated with lithium ions into graphite, exhibiting a staged structure. The stage number decreased from 4 to 1. During the scan from 1.00 to 2.44 V, the deintercalation of DMSO-solvated lithium ions was observed. After experienced a potential cycle between 2.4 and 0 V, the graphite exhibited significant changes that are ascribed to the exfoliation of graphite, implying that the destruction of the graphite composite electrode is likely to be caused by the decomposition of DMSO within the graphite layer.

Thin electrolyte films are frequently used in electrochemical systems. We have developed a powerful tool to reveal the current distribution in such films using segmented Pt array electrodes. In this study, this electrode system was applied to a polymeric film of an anion-exchange ionomer. We found that current distributions for oxygen reduction varied widely with the thickness of the ionomer films. A combination of experimental and simulation studies revealed that the transport of ions and oxygen molecules governed the currents in ionomer films.

Sodium-ion intercalation into the bulk of graphite hardly occurs. In this study, a nano-sized graphitizable carbon nanospheres (CNS) covered with basal planes were used to shorten the diffusion len...

Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) is a promising electrocatalyst for the oxygen evolution reaction (OER) in alkaline solution. The OER activities of BSCF are gradually enhanced by prolonging the duration of electrochemical operation at OER potentials, but the underlying cause is not fully understood. In this study, we investigated the role of chemical operation, equivalent to immersion in alkaline solution, in the time-course of OER enhancement of BSCF. Interestingly, the time-course OER enhancement of BSCF was promoted not only by electrochemical operation, which corresponds to potential cycling in the OER region, but also by chemical operation. In situ Raman measurements clarified that chemical operation had a lower rate of surface amorphization than electrochemical operation. On the other hand, the leaching behavior of A-site cations was comparable between chemical and electrochemical operations. Since the OER activity of BSCF was stabilized by saturating the electrolyte with Ba2+, “chemical” A-site leaching was key to inducing the time-course OER enhancement on perovskite electrocatalysts. Based on these results, we provide a fundamental understanding of the role of chemical operation in the OER properties of perovskites.

As negative electrode materials for lithium-ion batteries, graphitized carbon nanospheres (GCNSs) exhibit excellent capacity retention and high-rate capability. GCNSs with diameters less than 1 μm possess core–shell structures with a low graphitized core and an outer graphitized shell arranged in a concentric orientation. In the present work, the structural changes in GCNSs with various sizes and heat-treatment temperatures during lithium-ion intercalation and deintercalation were examined. Charge–discharge measurements and in situ Raman spectroscopy were used to investigate the origin of the specific electrochemical properties of GCNSs. The results indicated that GCNSs with small sizes and low heat-treatment temperatures did not exhibit the formation of stages 4 and 3 during lithium-ion intercalation and deintercalation. In addition, phase transition between different stage structures was ambiguous. This behavior was related to the disordered stacking structures of the outer graphene layers. In addition to the decreased size that increased the specific surface area and reduced the lithium-ion diffusion length within a particle, the high-rate capability of GCNSs can be ascribed to the monotonous and moderate structural changes. The excellent capacity retention can also be attributed to the specific structure of GCNSs.

Aqueous solutions have attracted considerable attention for use in aqueous-based energy-conversion devices such as aqueous lithium-ion batteries. While aqueous solutions have some desirable properties as electrolyte solutions, one drawback is the narrow potential window of water due to the electrolysis reactions of water (oxygen/hydrogen evolution reaction, OER/HER). Recently, it has been reported that the potential windows were expanded in concentrated electrolyte solutions. In this study, we investigated the potential windows in aqueous concentrated electrolyte solutions with various salts at different concentrations. A neutral pH solution with the lowest water concentration showed the largest potential window, and the potential windows were not affected by the electrolyte salts. In addition, we observed an asymmetric expansion of potential windows: the upper potential limits were shifted more than the lower limits. This can be explained by the local pH change in the vicinity of electrodes caused by OER/HER and the decrease in the rate of OER due to the reduced water concentrations.

Thin liquid electrolyte films are frequently used in electrochemical systems, such as energy devices and sensors, where they play an important role in determining the performance of such devices. However, it is difficult to experimentally determine the electrochemical behavior of these thin liquid films on electrodes. Here we investigated the uneven distribution of currents on an electrode covered with a thin liquid electrolyte film using a segmented Pt array electrode. A combination of experimental and simulation studies revealed that local ionic resistances governed the active positions of electrodes for the oxygen reduction reaction. These results demonstrate that segmented array electrodes are powerful tools for investigating the unique electrochemical features of thin liquid electrolyte films. Keywords: Liquid films, Current distribution, Array electrodes, Gas diffusion electrodes

Carbonaceous materials have been used as conductive materials for the composite electrodes in lithium-ion batteries (LIBs). Since an increase in the amount of conductive material implies a decrease in the capacity of the LIB, the amount of conductive material used should be kept to a minimum. Carbonaceous materials as conductive materials have various morphology and crystallinity, therefore, the fundamental study of carbonaceous materials as conductive materials is important. In this study, the electronic conductivity of electrode-slurries and composite electrodes prepared using different carbonaceous materials (acetylene black (AB), fine graphite, and vapor grown carbon fiber (VGCF)) as the conductive material was investigated, and the effect of the different carbonaceous materials on the electron conduction network was discussed. In the electrode-slurry, AB and VGCF formed electron conduction paths and displayed high electronic conductivity. The electrode-slurry of AB displayed solid-like behavior, whereas the electrode-slurries of VGCF and graphite displayed fluid-like behavior. This difference influenced the electronic conductivity of the composite electrode.

Metal oxide coating on positive active materials in lithium-ion batteries is an effective way to improve its cycleability. However, coating state of the metal oxide layer and the mechanism of the improvement have not been fully understood. In this paper, the coated state of ZrO2 on a LiCoO2 thin-film electrode was investigated using a ferrocene redox reaction, and the role of the ZrO2-coating on the degradation phenomena of the LiCoO2 was investigated. The redox behavior of ferrocene revealed that the ZrO2 layer did not cover the entire surface area of LiCoO2, that is, the ZrO2 layer was not compact and contained cracks. In addition, a lithium-ion deficit phase (Li1−x CoO2) was irreversibly formed on the uncovered LiCoO2 areas. In spite of the imperfect ZrO2 layer, the formation of the lithium-ion deficit phase inside the bulk was suppressed. It is clarified that a partial ZrO2 coating on the LiCoO2 is sufficient to suppress the growth of the lithium-ion deficit phase inside the bulk of LiCoO2.

Here, we describe a procedure to fluorescently contrast the nuclear boundary using the lipophilic carbocyanine dye DiI in cultured human cells. Our procedure is simple and is applicable to detect nuclear boundary defects, which may be relevant to studies on nuclear envelope dynamics, micronuclei formation and cancer biology. Abbreviations DiI: 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate; DiO: 3,3ʹ-dioctadecyloxacarbocyanine perchlorate; NE: nuclear envelope; RanBP2: Ran-binding protein 2/Nucleoporin 358

Abstract Background: The pathological findings of tonsils in IgA nephropathy include the expansion of T-cell nodules around lymphoid follicles and abnormal reticulation of the crypt epithelium in contrast to chronic tonsillitis. Recently, several studies have reported that regulatory T cells play an important role in the maintenance of self-tolerance, an abnormality that is involved in the onset of nephrotic syndrome (NS). We encountered a patient of 28-year-old male with frequently relapsing nephrotic syndrome (FRNS) and chronic tonsillitis whose tonsils demonstrated pathological findings similar to those of IgA nephropathy. Case presentation A patient had developed NS at the age of 5 years, and was pathologically diagnosed with minimal change disease (MCD), for which he received various immunosuppressive agents as treatment for recurrence. Because tonsillitis often triggers the recurrence of NS, a tonsillectomy was performed for chronic tonsillitis at the age of 25 years. Immunohistochemical staining of his tonsils showed the expansion of CD4 positive lymphocytes around the lymphoid follicles and abnormal reticulation of the crypt epithelium. The number of peripheral blood CD4+CD25+ regulatory T cells increased, and the frequency of relapses decreased after tonsillectomy. Conclusion A similar self-tolerance abnormality exists in NS and IgA nephropathy; therefore, tonsillectomy might become a novel therapeutic approach for FRNS to redress the unbalanced self-tolerance and to remove the tonsillar focal infection. Further studies are necessary to verify the clinical efficiency of tonsillectomy for FRNS with recurrent episodes triggered by tonsillitis.