Nanoflower-Like High-Entropy Co-Fe-Cr-Mo-Mn Spinel for Oxygen Evolution.

Oxygen evolution reaction (OER) is the key anode reaction of electrolytic water. To improve the slow OER kinetics, we synthesize nanoflower-like Co-Fe-Cr-Mo-Mn high-entropy spinel (HES) nanosheets on nickel foam (NF) by one-step solvothermal method, which exhibit an overpotential (η10) of only 188 mV at 10 mA cm-2, much lower than bimetallic CoFeOx/NF (233 mV), trimetallic CoFeCrOx/NF (211 mV), and tetrametallic CoFeCrMoOx/NF (200 mV). The OER overpotential decreases with the increase of the number of metals, indicating that the formation of HES has a positive effect on the improvement of electrocatalytic performance, since the synergistic effect between different metals enhances the charge transfer rate and decreases reaction barrier. In-situ Raman spectra demonstrate that the formation of γ-NiOOH on the HES surface is a crucial active species for the OER. This work demonstrates a simple and efficient synthesis method to prepare nanoflower-like high-entropy electrocatalysts for efficient OER electrocatalysis.

The causal association between COVID-19 and herpes simplex virus: a Mendelian randomization study.

Introduction: The coronavirus disease 2019 (COVID-19) has emerged as a main global public health challenge. Additionally, herpes simplex virus type-1 (HSV-1) and type 2 (HSV-2) are widespread viruses that can cause orolabial herpes and genital herpes. Several clinical case reports have declared a possible association between the two, however, the causal relationship between them has not been clarified. Methods: This study utilized a Mendelian randomization (MR) approach for causality assessment between COVID-19 infection and HSV infection based on the latest public health data and Genome-Wide Association Study (GWAS) data. Multiple causal estimation methods, such as IVW, weighted median, simple mode, and weighted mode, were employed to validate the causal relation between COVID-19 infection and HSV infection, with COVID-19 infection, COVID-19 hospitalization, and severe COVID-19 as exposures, and HSV1/2 infection as the outcome. A reverse MR analysis was subsequently performed. Results: MR analysis exhibited that COVID-19 infection was relevant to a reduced risk of HSV1 infection (p=7.603239e-152, OR=0.5690, 95%CI=0.5455-0.5935, IVW). Regarding the effect of COVID-19 infection on HSV2, MR analysis suggested that COVID-19 infection was correlated with an augmented risk of HSV2 infection (p=6.46735e-11, OR=1.1137, 95%CI=1.0782-1.1502, IVW). The reverse MR analysis did not demonstrate a reverse causal relationship between HSV and COVID-19. Discussion: Altogether, COVID-19 infection might cause a decreased risk of HSV1 infection and an elevated risk of HSV2 infection.

Optimization strategies of high-entropy alloys for electrocatalytic applications.

High-entropy alloys (HEAs) are expected to become one of the most promising functional materials in the field of electrocatalysis due to their site-occupancy disorder and lattice order. The chemical complexity and component tunability make it possible for them to obtain a nearly continuous distribution of adsorption energy curve, which means that the optimal adsorption strength and maximum activity can be obtained by a multi-alloying strategy. In the last decade, a great deal of research has been performed on the synthesis, element selection and catalytic applications of HEAs. In this review, we focus on the analysis and summary of the advantages, design ideas and optimization strategies of HEAs in electrocatalysis. Combined with experiments and theories, the advantages of high activity and high stability of HEAs are explored in depth. According to the classification of catalytic reactions, how to design high-performance HEA catalysts is proposed. More importantly, efficient strategies for optimizing HEA catalysts are provided, including element regulation, defect regulation and strain engineering. Finally, we point out the challenges that HEAs will face in the future, and put forward some personal proposals. This work provides a deep understanding and important reference for electrocatalytic applications of HEAs.

In situ synthesis of rosette-like Co-doped FeNiOOH/NF for seawater oxidation.

The development of high activity and strong resistance to seawater corrosion oxygen evolution reaction (OER) electrocatalysts for seawater electrolysis has broad application prospects. Herein, we prepare Co-doped FeNiOOH rosette-like nanoflowers on nickel foam (NF) with different Co dosages by one-step solvothermal method. The Co0.2-FeNiOOH/NF exhibits a low overpotential (η10) of 185 mV and Tafel slope of 30 mV dec-1 in 1 M KOH. Moreover, it shows a low η10 of 244 mV in alkaline seawater electrolyte. The remarkable OER performance of Co0.2-FeNiOOH/NF is ascribed to the fact that the introduction of Co regulates the morphology and electron structure of the material, which provides abundant active sites for the reaction and promotes charge transfer. In situ Raman results demonstrate that NiOOH and γ-FeOOH are the key active species for the OER. This study provides a feasible basis for seawater electrolysis over transition metal (oxy)hydroxides.

Correlations between gut microbiota and lichen planus: a two-sample Mendelian randomization study.

Purpose: Several existing studies have revealed that the occurrence of lichen planus (LP) is relevant to the gut microbiota, and the causal relationship between gut microbiota and LP was analyzed using the Mendelian randomization (MR) method. Methods: Through the two-sample MR method, single nucleotide polymorphisms (SNPs) relevant to gut microbiota were selected as instrument variables (IVs) to evaluate the causal association between gut microbiota and the risk of LP. Results: According to the selection criteria of inverse-variance weighted (IVW), six bacterial genera were found to be significantly linked to the initiation of LP; The IVW results suggested that Oxalobacteraceae, Victivallaceae, and Actinobacteria could restrain the initiation of LP, showing protective effects against LP. Desulfovibrio, Veillonella, and Ruminococcus gauvreauii groups were demonstrated to have casual correlations with the onset of LP. Conclusion: The relationship between gut microbiota and LP was not a single positive or inverse relationship. Investigation of the causal relationship of these gut microbiota with LP could further provide evidence for the intestine-skin axis theory. However, the specific mechanism of microorganisms affecting the skin remains to be clarified. In this paper, the protective effects and mechanisms of Oxalobacteraceae, Victivallaceae, and Actinobacteria on LP require further exploration.

Nanoflower-like high-entropy Ni-Fe-Cr-Mn-Co (oxy)hydroxides for oxygen evolution.

High-entropy materials (HEMs) have potential application value in electrocatalytic water splitting because of their unique alloy design concept and significant mixed entropy effect. Here, we synthesize a high-entropy Ni-Fe-Cr-Mn-Co (oxy)hydroxide on nickel foam (NF) by a solvothermal method. The flower-like structure of FeNiCrMnCoOOH/NF can provide abundant active sites, thus improving the oxygen evolution reaction (OER) activity. In 1 M KOH, the FeNiCrMnCoOOH/NF shows an ultra-low overpotential (η10) of 201 mV for the OER, superior to FeNiCrMnAlOOH/NF, FeNiCrMnCuOOH/NF, FeNiCrMnMoOOH/NF, and FeNiCrMnCeOOH/NF. In addition, it exhibits a low η10 of 223 mV in 0.5 M NaCl + 1 M KOH and excellent stability. Electrochemical impedance spectroscopy measurements indicate that the synergistic effect between multiple metals accelerates charge transfer, while in situ Raman measurements reveal that NiOOH is a key active species for the OER. This work is of great significance for the construction of high-entropy (oxy)hydroxides for seawater electrolysis.

The study of diffusion kinetics of cinnamaldehyde from corn starch-based film into food simulant and physical properties of antibacterial polymer film.

Corn starch-based films containing cinnamon essential oil were prepared. The physical properties of the films, and the diffusion kinetics of cinnamaldehyde were analyzed. The results showed that the antibacterial polymer film containing 2.0% (w/v) cinnamon essential oil had the acceptable physical properties with the tensile strength and the elongation at break of 22.53 ±â€¯0.16 MPa and 20.07 ±â€¯1.18%, respectively. The diffusion kinetics of cinnamaldehyde followed Fick's diffusion law. The diffusion percentage of cinnamaldehyde into 10% ethanol was lower than that of 95% ethanol. For short-term diffusion into 95% ethanol, the estimated n-values were between 0.1736 and 0.3519 and the diffusion coefficient (Dp) was increased with the increase of temperature. For long-term diffusion into 95% ethanol, the Dp values were decreased by 105-106 times in relative to short-term diffusion, and the partition coefficient (KP,F) was decreased with the increase of temperature. The antibacterial polymer film containing 2.0% cinnamon essential oil exhibited antibacterial activity for over 120 days.

Synthesis of Y2O2S:Eu3+, Mg2+, Ti4+ hollow microspheres via homogeneous precipitation route.

A phosphorescent material in the form of Y2O2S:Eu3+, Mg2+, Ti4+ hollow microspheres was prepared by homogeneous precipitation using monodispersed carbon spheres as hard templates. Y2O3:Eu3+ hollow microspheres were first synthesized to serve as the precursor. Y2O2S:Eu3+, Mg2+, Ti4+ powders were obtained by calcinating the precursor in a CS2 atmosphere. The crystal structure, morphology and optical properties of the composites were characterized. X-ray diffraction measurements confirmed the purity of the Y2O2S phase. Electron microscopy observations revealed that the Y2O2S:Eu3+, Mg2+, Ti4+ particles inherited the hollow spherical shape from the precursor after being calcined in a CS2 atmosphere and that they had a diameter of 350-450 nm and a wall thickness of about 50-80 nm. After ultraviolet radiation at 265 or 325 nm for 5 min, the particles emitted strong red long-lifetime phosphorescence originating from Eu3+ ions. This phosphorescence is associated with the trapping of charge carriers by Ti4+ and Mg2+ ions.

Synthesis of monodisperse spherical core-shell SiO2-SrAl2Si2O8: Eu2+ phosphors by hydrothermal homogeneous precipitation method.

Nanocrystalline SrAl2Si2O8 :Eu2+ phosphor layers were coated on nonaggregated, monodisperse and spherical SiO2 particles using a hydrothermal homogeneous precipitation. After annealing at 1100 °C, core-shell SiO2@SrAl2Si2O8 :Eu2+ particles were obtained. They were characterized with x-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy and photoluminescence techniques. XRD analysis confirmed the formation of SiO2 @SrAl2Si2O8 :Eu2+ particles; it indicated that the SrAl2Si2O8 :Eu2+ shells on SiO2 particles consisted of hexagonal crystallites. The core-shell phosphors obtained are well-dispersed submicron spherical particles with a narrow size distribution. The thickness of the coated layer is approximately 20-40 nm. Under ultraviolet excitation (361 nm), the particles emit blue light at about 440 nm due to the Eu2+ ions in their shells.