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Anodic porous oxides with ordered nanohole array structures were prepared by the formation of concave arrays on the surface of Cu, Zn, and Ni substrates and the subsequent anodization of the prepatterned substrates. The concave arrays on the surface of the substrate were formed by Ar ion milling using an alumina mask. Although the anodization of Cu, Zn, and Ni substrates without prepatterning generates spongelike porous structures, ordered arrays of cylindrical nanoholes were obtained by the anodization of prepatterned substrates. The interpore distance of the obtained nanohole arrays was controlled by changing the period of the concave arrays. Crystallized ordered nanohole arrays of Cu

The composites of a high-capacity cathode material in lithium-ion batteries, LiCoO2 and an oxide-based solid electrolyte, Li1.3Al0.3Ti1.7(PO4)3 were sintered at various temperature and their reaction products were identified by XRD and XANES.

We evaluated the structural change of the cathode material Li2MnO3 that was deposited as an epitaxial film with an (001) orientation in an all-solid-state battery. We developed an in situ surface X-ray diffraction (XRD) technique, where X-rays are incident at a very low grazing angle of 0.1°. An X-ray with wavelength of 0.82518 A penetrated an ∼2 μm-thick amorphous Li3PO4 solid-state electrolyte and ∼1 μm-thick metal Li anode on the Li2MnO3 cathode. Experiments revealed a structural change to a high-capacity (activated) phase that proceeded gradually and continuously with cycling. The activated phase barely showed any capacity fading. First-principles calculations suggested that the activated phase has O1 stacking, which is attained by first delithiating to an intermediate phase with O3 stacking and tetrahedral Li. This intermediate phase has a low Li migration barrier path in the [001] direction, but further delithiation causes an energetically favorable and irreversible transition to the O1 phase. We propose a mechanism of structural change with cycling: charging to a high voltage at a sufficiently low Li concentration typically induces irreversible transition to a phase detrimental to cycling that could, but not necessarily, be accompanied by the dissolution of Mn and/or the release of O into the electrolyte, while a gradual irreversible transition to an activated phase happens at a similar Li concentration under a lower voltage.

Two-dimensional (2D) boron monosulfide (BS) nanosheets are predicted to have several stable phases and unique electronic structures, endowing them with interesting attributes, including superconducting, thermoelectric, and hydrogen storage properties. In this paper, we report the experimental realization of 2D BS nanosheets by the physical exfoliation of rhombohedral boron monosulfide (r-BS). Moreover, we demonstrate the facile separation of a mixture of 2D BS nanosheets and the r-BS powder in acetonitrile; the former were selectively separated as a dispersion in the supernatant, whereas the latter remained in the precipitate. In addition, density functional theory calculations reveal a clear dependence of the bandgap energy (Eg) on the number of layers of stacked BS nanosheets, where Eg for BS nanosheets is approximately 1.0 eV higher than that for r-BS. Atomic force microscopy, cathode luminescence, ultraviolet-visible absorption spectroscopy, and excitation emission matrix experiments revealed a consistent bandgap difference of approximately 1.0 eV between the BS nanosheets and r-BS. We also demonstrate the applications based on the properties that originated from the difference in the bandgap between r-BS and BS nanosheets using photoelectrochemical current switching. These results indicate that the nanosheet bandgap can be tuned to a desired value by controlling the number of stacked 2D BS nanosheets. Therefore, BS nanosheets are promising non-metal 2D materials for applications requiring bandgap control, such as electronics and photocatalysis.

Aim: We present the study protocol of a multicenter, retrospective observational study that aims to investigate the efficacy of the actual treatment (the efficacy of conventional and Kampo medicines) of patients with mild to moderate or suspected coronavirus disease (COVID-19) Methods: This study is designed as a multicenter, retrospective observational study Outpatients and inpatients will be recruited from Japanese hospitals The inclusion criteria are as follows: having or suspected to have COVID-19, mild to moderate COVID-19, symptomatic, ≥20 years of age, male or female, able to communicate in Japanese, and treated with conventional and Kampo medicine The exclusion criteria are: unable to provide informed consent due to dementia, psychosis, or psychiatric symptoms, severe COVID-19, or determined unsuitable for this study The sample size is set at 1000, as this number of people can be treated at the collaborating medical institutions during the study period Results: The main outcome is the number of days without fever, with a body temperature of less than 37°C The secondary outcome is set at common cold-like symptoms other than fever (fatigue, cough, shortness of breath, sputum, diarrhea) and severity of illness and hospitalization up to 14 days after the visit Trial registration: The trial was registered in the University Hospital Medical Information Network (Reservation No UMIN000041301) on August 4, 2020 Conclusion: Our study will explore the contribution of conventional and Kampo medicine in the treatment of patients with mild and moderate COVID-19

Passivation of the n-InP(100) surface with sodium sulfide (Na2S) aqueous solution is analyzed by photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). The room-temperature PL intensity increases essentially even after short treatment with sulfide solution for 1 min. The enhancement in the room-temperature PL intensity after passivation decreases with the increase in the bulk doping level of the semiconductor. Time-resolved PL studies performed at liquid-nitrogen temperature indicate reduction in the surface recombination velocity. This improvement of the PL intensity occurs just after transformation of the native oxide layer consisting mainly of indium phosphates to the passivating layer consisting of indium sulfides and oxides. The surface bands in n-InP(100) remained nearly flat both before and after sulfide passivation.

The adsorption behavior of perfluorosulfonated ionomers (PFSIs) on a Pt(111) surface in various solvents is investigated by in situ atomic force microscopy (AFM) and discussed on the basis of aggregation of PFSIs in the liquid phase. The AFM images show that, in an aqueous solution of PFSI (0.1 wt % Nafion + 99.9 wt % water), PFSI aggregates with a lateral size of 20-200 nm adsorb on the Pt(111) surface. In a PFSI solution containing a small amount of 1-propanol (0.1 wt % Nafion + 99.5 wt % water + 0.4 wt % 1-propanol), however, slightly smaller aggregates adsorb on the Pt(111) surface. Such solvent-dependent sizes of adsorbed aggregates are in reasonable agreement with apparent hydrodynamic radii of PFSIs in the corresponding solutions determined by dynamic light scattering (DLS) while assuming the formation of spherical aggregation. Interestingly, a step-terrace structure characteristic to a clean Pt(111) surface is observed in a propanol-rich PFSI solution (0.1 wt % Nafion + 44.45 wt % water + 55.45 wt % 1-propanol) but X-ray photoelectron spectroscopy clearly indicates the existence of fluorocarbon species at the Pt(111) surface, suggesting the formation of a smooth adsorbed layer of PFSIs in a lying down configuration. Absence of any features assignable to aggregates in DLS data suggests well-dispersion of PFSIs in such propanol-rich solution without aggregations. Thus, the adsorbed structure of PFSIs at Pt surfaces can be controlled by tuning the composition of mixed solvent, which affects the aggregation of PFSI in the liquid phase.

Polymer electrolyte fuel cells (PEFCs) are one of the most attractive power sources, especially for electric vehicles, because of their very high theoretical energy conversion efficiency and extrem...

Water molecules within a thin hydration layer, spontaneously generated on hydrophobic protein surfaces, are reported to form a poorly dynamic network structure. However, how such a water network affects the conformational change dynamics of polar groups has never been explored, although such polar groups play a critical role in protein-protein and protein-ligand interactions. In the present work, we utilized as model protein surfaces a series of self-assembled monolayers (SAMs) appended with polar (Fmoc) or ionic (FITC) fluorescent head groups that were tethered via a 1.5-nm-long flexible oligoether chain to a hydrophobic silicon wafer surface, which was densely covered with paraffinic chains. We found that, not only in deionized water but also in aqueous buffer, these oligoether-appended head groups at ambient temperatures both displayed an anomalously slow conformational change, which required ∼10 h to reach a thermodynamically equilibrated state. We suppose that these behaviors reflect the poorly dynamic and low-permittivity natures of the thin hydration layer.

In situ X-ray photoelectron spectroscopy is applied to electrochemical lithiation/delithiation processes of an amorphous Si electrode sputter-deposited on a Li6.6La3Zr1.6Ta0.4O12 solid electrolyte. After the first lithiation, a broad Li peak appears at the Si surface, and peaks corresponding to bulk Si and Si suboxide significantly shift to lower binding energy. The appearance of the Li peak and shift of the Si peaks confirm the formation of lithium-silicide and lithium-silicates due to the lithiation of Si and native suboxide. The composition of lithium-silicide is estimated to be Li3.44Si by quantitative analysis of electrochemical response and photoelectron spectra. Peak fitting analysis shows the formation of Li2O and Li2CO3 due to side reactions. Upon the following delithiation, the peak corresponding to Li3.44Si phase shifts back to higher binding energy to form Li0.15Si phase, while lithium-silicates, Li2O, and Li2CO3 remained as irreversible species. Thus, electrochemical reactions accompanied with lithiation/delithiation processes are successfully observed.

Natural convection of a low-Prandtl-number conductive fluid driven by a horizontal temperature gradient in an annular enclosure with a square cross section was investigated. The surface temperatures of the inner and outer cylinders were differentially maintained. A static magnetic field was applied in the azimuthal direction. A three-dimensional (3D) numerical simulation was performed for a part of an annulus divided into 20 or 28 equal parts. The natural convection found changes on the order of a two-dimensional (2D) steady, a 3D steady, a 3D non-half-symmetric simply periodic oscillatory, a 3D indefinite oscillatory, a 3D half-symmetric simply periodic oscillatory, and a 3D aperiodic oscillatory flow as the Hartmann number decreases. This transition pattern is identical to that as the Rayleigh number increases in the same system without a magnetic field. In high Rayleigh numbers, the transition is accompanied by an axisymmetric oscillation. A disturbance causing the transition consists of three modes as a 3D steady, a 3D half-symmetric oscillatory, and a 2D axisymmetric oscillatory mode. The Nusselt numbers in most 3D flows are smaller at low Rayleigh numbers and larger at high Rayleigh numbers than that in 2D flows at a same condition, while the kinetic energy of a 3D flow is necessarily smaller than that of a 2D flow.

In order to quantitatively grasp the influence of asymmetry of a channel, flow in an eccentric sudden expansion channel, in which the channel centers are different on the upstream and downstream sides, was calculated to be less than the Reynolds number of 400, where the expansion rate was 2. The asymmetry of a channel is expressed by an eccentricity S, where a symmetric expansion channel is S = 0 and a channel with one side step is S = 1. Both flows firstly reattached on the wall located on the short and long side of a sudden expansion and were observed in the range of S ≤ 0.2, although only the former was seen in the range of S &gt, 0.2. The critical Reynolds number of the multiple solutions increases parabolically to S. At least two separation vortices occur, and the third separation vortex is generated in both solutions above the critical Reynolds number of the third vortex. The length of an entrance region increases linearly to the Reynolds number and slightly with the increase in S. The pressure drop coefficient is proportional to the power of the Reynolds number and increases with S.

We aimed to identify the neurotransmitters and brain regions involved in exercise efficiency in mice during continuous complicated exercises. Male C57BL/6J mice practiced treadmill running with intermittent obstacles on a treadmill for 8 days. Oxygen uptake (VO2) during treadmill running was measured as exercise efficiency. After obstacle exercise training, the VO2 measured during treadmill running with obstacles decreased significantly. Obstacle exercise-induced c-Fos expressions and dopamine turnover (DOPAC/dopamine) in the septum after obstacle exercise training were significantly higher than that before training. The dopamine turnover was correlated with exercise efficiency on the 3rd day after exercise training. Furthermore, the training effect on exercise efficiency was significantly decreased by injection of dopamine receptor antagonists into the septum and was associated with decreased c-Fos expressions in the septum and hippocampus of the mice. These results suggest that dopaminergic function in the septum is involved in exercise efficiency during continuous complicated exercises.

Various important processes, such as electron transfer reactions, adsorption/desorption, solvation/desolvation, and formation/cleavage of chemical bonds, take place at electrolyte/electrode interfaces during electrocatalytic reactions. Those processes have been understood on the basis of changes in the surface composition, atomic arrangement, and molecular and electronic structures of the interfaces by using various in situ analysis techniques. To date, in situ analysis and observation of those interfacial processes at an ideal single-crystal surface are indispensable not only for fundamental understanding of the reaction mechanism but also for rational design of the highly efficient and durable electrocatalytic materials. Here, historical and recent progress of in situ studies on electrocatalytic reactions is briefly reviewed with a focus on two major techniques, X-ray absorption fine structure and surface X-ray scattering.

All-solid-state lithium-ion batteries (ASSLIBs) with oxide-based solid electrolytes are a promising candidate for next generation of rechargeable batteries, due to their reliability and high-energy density. The formation of well-defined electrode/solid electrolyte interfaces with an excellent ionic conductivity by co-sintering is one of the key challenges to develop oxide-based ASSLIBs.1 Electrode materials and solid electrolytes often react with each other to form a resistive substance at their interface during co-sintering.2-4 Thus, optimization of the co-sintering conditions is important to control the interfacial structure which governs the ionic conductivity. However, the effect of the interfacial structure on the ionic conductivity remains unclear. In this study, we co-sintered the composites of LiCoPO4 (LCP) electrode material and Li1.3Al0.3Ti1.7(PO4)3 (LATP) oxide-based solid electrolyte and investigated the interfacial structure by using X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) and scanning transmission electron microscopy combined with electron energy loss spectroscopy and an energy-dispersive X-ray spectroscopy (STEM-EELS/EDX). Figure 1(a) shows the XRD patterns of the LCP/LATP composites before and after sintering at 800°C. The diffraction patterns are almost identical to each other and all the diffraction peaks are attributed to the LCP and LATP with an exception of AlPO4 impurity. However, the Co K-edge XANES is slightly changed after sintering as shown in Figure 1(b). These results suggest that a small amount of LCP and LATP react with each other. Figure 1(c) shows a typical STEM image of the LCP/LATP composites after sintering at 800°C. According to EDX analysis, light and dark gray domains correspond to LCP and LATP, respectively. Apart from LCP and LATP, there are two types of LCP/LATP interfaces: interface A and B. Line profile STEM-EELS/EDX analysis revealed that LCP and LATP directly bound to each other at the interface A. On the other hand, a thermally reacted thin layer, possibly cobalt oxide (CoO) and/or cobalt phosphide (Co2P), is formed at interface B. The effect of such thermally reacted interlayer on the ionic conductivity will be discussed in detail. References: R. Chen, Q. Li, X. Yu, L. Chen and H. Li, Chemical Reviews, 2020, 120, 6820-6877. M. Gellert, E. Dashjav, D. Grüner, Q. Ma and F. Tietz, Ionics, 2017, 24, 1001-1006. C.-Y. Yu, J. Choi, V. Anandan and J.-H. Kim, The Journal of Physical Chemistry C, 2020, 124, 14963-14971. L. Miara, A. Windmuller, C. L. Tsai, W. D. Richards, Q. Ma, S. Uhlenbruck, O. Guillon and G. Ceder, ACS Applied Materials and Interfaces, 2016, 8, 26842-26850. Figure 1

Ordered anodic porous WO3 was prepared by the anodization of a W substrate with a depression pattern under a constant voltage of 18 V in concentrated phosphoric acid at 120 °C. However, the behavior of hole formation induced in depressions was found to be strongly affected by the depth and diameter of the depressions. Multiple holes were formed in a shallow depression during the initial stage of anodization, whereas only one hole was formed in a deep depression. In addition, when the depression diameter was small, the growth of fine holes around the induced holes was observed. Since the fine holes formed on the surface of anodic porous WO3 prevented the induced holes from growing in the depth direction, the formation of large-diameter depressions allowed the induced holes to grow deeper. The obtained ordered anodic porous WO3 can be used for various applications such as in photocatalysis and electrochromic devices.

A nanohole array structure with a regular array of cylindrical holes of a high aspect ratio with a period of 63 nm can be obtained by anodizing 304 stainless steel with a concave pattern. It was shown that matching the concave period to the anodization voltage is important to achieving the fabrication of nanohole arrays with a high aspect ratio. This is because the interhole distance of anodic porous oxide obtained by the anodization of 304 stainless steel in ethylene glycol containing 0.1 M ammonium fluoride depends on the anodization voltage. By optimizing the fabrication conditions, it was possible to fabricate highly ordered nanohole arrays with aspect ratios exceeding 100. The nanohole arrays obtained in this study are promising as key materials for fabricating various functional devices.

We evaluated the structural change of the cathode material Li

In this study, highly ordered anodic porous metal oxides of transition metals (W, Fe, Co, and Nb) were prepared by anodization combined with a pretexturing process. The formation of an array of dimples on the metal surface was achieved by dry etching using ordered anodic porous alumina as a mask. Subsequent anodization of the pretextured metals generated metal oxides (WO3, Fe2O3, Co3O4, and Nb2O4) with an ordered hole array structure because each dimple acted as a starting point for hole development. The hole periodicity of the resulting ordered anodic porous metal oxide could be controlled by changing the periodicity of the dimples formed on the substrate. Ordered anodic porous films obtained by this process could be used in various functional devices that require ordered hole array structures.

Interfacial phenomena of oxide cathode/sulfide electrolytes are crucial for the improvement of energy density and cycle stability of all-solid-state batteries. Thin-film batteries provide a simple reaction field for mechanistic studies. We fabricated a model film battery consisted of LiCoO2 cathode, LiNbO3 buffer layer, amorphous Li3PS4 electrolyte, and Li metal anode by physical vapor deposition. Structural changes at the cathode-side interface were investigated by in situ X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) using Ar etching. The LiCoO2 lattice showed a reversible change under high voltage operation with the upper cutoff voltage of 4.5 V. A cathode electrolyte interphase (CEI) layer was formed at the interface by decomposition of LiNbO3 and Li3PS4. The ionic and electronic conductivities of the CEI layer could be crucial to improve the reaction resistance and the cycle stability of the oxide cathode/sulfide electrolyte interface.

Nanoscale Young's modulus mapping of the cross-section of electrode composite films used in lithium ion batteries was carried out using bimodal atomic force microscopy. Clear difference in Young's modulus was observed between the particles of active materials and matrix of conductive additives/binders in the composites of LiCoO2-based positive and graphite-based negative electrodes. Interestingly, there were a few particles showing significantly reduced Young's modulus in the 100% state-of-charge positive electrode although such particles were not present in the pristine electrode.

A 40-year-old man with refractory ulcerative colitis (UC) was treated with tumor necrosis factor α inhibitor (anti-TNFα), infliximab. One month later, the chest computed tomography and laboratory test showed noninfectious interstitial lung disease (ILD) and elevation of serum Krebs von den Lungen-6 (KL-6). Fortunately, ILD disappeared after the discontinuation with anti-TNFα. Two and a half years after his first UC treatment, he was treated again with another anti-TNFα, adalimumab, for relapse and he had a second ILD. This course suggested anti-TNFα induced ILD. The characteristics of anti-TNFα-induced ILD in inflammatory bowel disease (IBD) are not well understood. We summarized and investigated the characteristics of such patients based on a literature review including 15 cases. It suggested that anti-TNFα-induced ILD in IBD might be rare and tends to have a better outcome compared with ILD in rheumatoid arthritis.

In the last several decades, a variety of surface analysis techniques which can probe the geometric/electronic/molecular structures of the interfaces, as well as the elemental composition, have been developed and applied for the investigation of electrochemical processes taking place at solid–liquid interfaces. Designing spectroelectrochemical cells is one of the big challenges for utilization of those techniques to a variety of electrochemical interfaces because the thickness of solution layers, materials used as a window, geometry of the photon source, sample, and spectrometer/analyzer/detector need to be optimal for the electrochemical reaction of interest and photons used in the individual techniques. To date, various unique spectroelectrochemical cells have been used for in situ electrochemical studies on interfacial processes even by using the techniques which intrinsically require vacuum. In this paper, recent progress on in situ spectroelectrochemical cells, especially used for X-ray photoelectron spectroscopy, is reviewed.

Silicon-cobalt nanocomposites on NrGO, Si-Co/NrGO, were synthesized by the modified polyol method. Rice husk was used as the silicon source. The composites were primarily characterized by x-ray diffraction, scanning electron microscopy, and transmission electron microscopy equipped with energy dispersive spectroscopy. The small-sized particles of the silicon-cobalt product were effectively distributed on the NrGO. Finally, these anode materials were tested in lithium-ion batteries by haft-coin cell assembly. Electrochemical properties were measured and the result showed an initial capacity of 975 mAh g-1. This material is expected to be used as a high-performance anode, suitable for the next generation of anode materials in lithium-ion batteries.

Correction for ‘Crystalline boron monosulfide nanosheets with tunable bandgaps’ by Haruki Kusaka et al., J. Mater. Chem. A, 2021, 9, 24631–24640, DOI: 10.1039/D1TA03307G.

Various important processes take place at solid/liquid interfaces. Understanding of structural changes accompanying with those interfacial processes is important not only for fundamental science but also for a wide range of applications, especially electrocatalysis. In the last several decades, a variety of microscopic and spectroscopic techniques have been developed to observe geometric/molecular/electronic structures at the solid/liquid interfaces in situ. However, techniques to probe the electronic structure of electrocatalysts are still limited because of the complexity of the experimental setup and the interpretation of results. Since the 1980s, our groups have developed and utilized various techniques which enable to investigate those structural changes under electrochemical potential control. In the present paper, our recent research progress on the electronic structure at solid/liquid interfaces, (1) in situ XAFS studies on molecular catalysts confined within molecular layers and electrocatalysts for oxygen reduction reaction in polymer electrolyte membrane fuel cells, (2) development of an in situ electrochemical XPS apparatus for the solid/liquid interfaces and (3) investigation of the electronic structure of metal surfaces modulated by adsorbed species by in situ DR-SFG is briefly reviewed.

Determining the atomic structure across electrolyte–electrode interfaces with a sufficient temporal resolution is crucial to understanding how electrochemical reactions proceed. Surface X-ray diffraction is a well-established method for determining interface structures at the atomic scale. However, existing measurement methods are often incapable of quantifying time-dependent structural changes during electrochemical processes because acquiring a diffraction rod profile sufficient for structure determination usually takes a longer time than the rate of the structural changes. This report demonstrates that the wavelength-dispersive method, which can acquire a range of the diffraction rod profile at once, is capable of the time-resolved analysis of electrochemical dynamics on a time scale of seconds and less, using electrochemical reactions on Pt(111) electrode surface as examples. In the case of the electrochemical oxidation of methanol, the quantitative analysis of the transient vertical displacement of t...

Room temperature (RT) bistable switching materials continue to fascinate the scientists since they can be utilized for a new class of molecular-based switches or memories. While the spin crossover (SCO) compound is categorized into these attractive materials, designing of a SCO system showing desirable bistability (i.e., wide hysteresis loop spanning RT) in a rational way is still a very challenging issue. We report herein a new family of neutral molecular iron(II) complexes showing hysteretic SCO in a wide range of switching temperatures (239–409 K) and hysteresis widths (1–31 K) spanning RT. These materials were obtained as single crystals of two solvent-free compounds [FeII(ptm2-dmpn)(NCS)2] (1; ptm2-dmpn = N,N′-bis[(1-phenyl-1H-1,2,3-triazol-4-yl)methylene]-2,2-dimethylpropane-1,3-diamine) and [FeII(p-ttm2-dmpn)(NCS)2] (2; p-ttm2-dmpn = N,N′-bis[(1-p-tolyl-1H-1,2,3-triazol-4-yl)methylene]-2,2-dimethylpropane-1,3-diamine), and two solvatomorphs [FeII(p-ttm2-etpn)(NCS)2]·solvent (p-ttm2-etpn = N,N′-bis[...