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Fuel cells are considered as a promising alternative to the existing traditional energy systems towards a sustainable future. Nevertheless, the synthesis of efficient and robust platinum (Pt) based catalysts remains a challenge for practical applications. In this work, we present a simple and scalable molten‐salt synthesis method for producing a low‐platinum (Pt) nanoalloy implanted in metal–nitrogen–graphene. The as‐prepared low‐Pt alloyed graphene exhibits a high oxygen reduction activity of 1.29 A mgPt−1 and excellent durability over 30 000 potential cycles. The catalyst nanoarchitecture of graphene encased Pt nanoalloy provides a robust capability against nanoparticle migration and corrosion due to a strong metal–support interaction. Similarly, advanced characterization and theoretical calculations show that the multiple active sites in platinum alloyed graphene synergistically account for the improved oxygen reduction. This work not only provides an efficient and robust low‐Pt catalyst but also a facile design idea and scalable preparation technique for integrated catalysts to achieve more profound applications in fuel cells and beyond. [ABSTRACT FROM AUTHOR]

Activities of FeO in CaO-SiO2-Al2O3-MgO-FeO slags were determined at 1 673 K by electrochemical measurements of the solid electrolyte cell: Mo |Mo+MoO2|ZrO2(MgO)|Fe+(CaO-SiO2-Al2O3-MgO-FeO)+Ag|Fe. The influences of slag compositions and basicity on FeO activities were analyzed. The results reveal that, for slags of fixed (%CaO)/(%SiO2) ratio, MgO and Al2O3 content, there was an increase of FeO activities with increase of FeO content. For slags with constant {(%CaO)+ (%MgO)}/(%SiO2) ratio, fixed FeO and Al2O3 content, FeO activities decreased when MgO content increased from 5% to 10%, and increased with the increase of MgO content when it was over 10%. The FeO activities increased when (%CaO)/(%SiO2) ratio changed from 1.03 to 1.30 in the slags of constant MgO, FeO and Al2O3 content. [ABSTRACT FROM AUTHOR]

The electrochemical reduction reaction of carbon dioxide (CO 2 RR) into valuable products offers notable economic benefits and contributes to environmental sustainability. However, precisely controlling the reaction pathways and selectively converting key intermediates pose considerable challenges. In this study, our theoretical calculations reveal that the active sites with different states of copper atoms (1-3-5-7-9) play a pivotal role in the adsorption behavior of the *CHO critical intermediate. This behavior dictates the subsequent hydrogenation and coupling steps, ultimately influencing the formation of the desired products. Consequently, we designed two model electrocatalysts comprising Cu single atoms and particles supported on CeO 2 . This design enables controlled *CHO intermediate transformation through either hydrogenation with *H or coupling with *CO, leading to a highly selective CO 2 RR. Notably, our selective control strategy tunes the Faradaic efficiency from 61.1% for ethylene (C 2 H 4 ) to 61.2% for methane (CH 4 ). Additionally, the catalyst demonstrated a high current density and remarkable stability, exceeding 500 h of operation. This work not only provides efficient catalysts for selective CO 2 RR but also offers valuable insights into tailoring surface chemistry and designing catalysts for precise control over catalytic processes to achieve targeted product generation in CO 2 RR technology.

Revealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO 2 into ethylene (C 2 H 4 ), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low-coordination copper-based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm -2 . Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full-cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO 2 RR) catalysts but also advances CO 2 electrolysis technologies for industrial application., (© 2024 Wiley‐VCH GmbH.)

Objective: To study the protective effects of astaxanthin liposome (Asx-lipo) on photodamage by UVB in mice skin., Methods: 40 C57BL/6J mice were randomly divided into four groups: The blank group (no irradiation, no drug use), model group (UVB light injury group, no drug use), control group (irradiation + astaxanthin), experimental group (irradiation + astaxanthin liposome), each group with 10 mice. Each group was given the corresponding light (the radiation intensity was 2 mW·cm 2 , the time of irradiation was 60 s, 1 times a day for the first 5 days, and 1 times every other day for the next 9 days, 10 times in a total of 2 weeks.) and drug intervention (topically treated with 4 mL 0.2‰ astaxanthin or 4 mL 0.2‰ Asx-lipo 10 min before the irradiation) for two weeks. After that, samples were examined by the following indicators: the histological changes of skin, Ki-67, 8-hydroxy-2'-deoxyguanosine(8-OHdG), superoxide dismutase(SOD) activities and serum matrix metalloproteinase-13 (MMP-13)., Results: HE staining the model group and the control group showed that the dermis became thin, the dermal collagen fibers were long and thin, and the arrangement was loose and disordered. Compared with the blank group, the expression of Ki-67, MMP-13 and 8-OHdG increased and SOD activity decreased, and the differences were statistically significant ( P <0.05). Compared with the model group, the pathological changes of skin tissues in the experimental group were significantly improved, with decreased expressions of Ki-67, MMP-13 and 8-OHdG and increased SOD activity, and the differences were statistically significant ( P <0.05)., Conclusion: The photodamage of mice skin can be improved by topical Asx-lipo. The mechanism may be related to the strong antioxidation of Asx-lipo., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Science Edition).)

Electronic coupling across a bridging ligand between a chromophore and a catalyst center has an important influence on biological and synthetic photocatalytic processes. Structural and associated electronic modifications of ligands may improve the efficiency of photocatalytic transformations of organic substrates. Two ruthenium-based supramolecular assemblies based on a chromophore-catalyst dyad containing a Ru-aqua complex and its chloro form as the catalytic components were synthesized and structurally characterized, and their spectroscopic and electrochemical properties were investigated. Under visible light irradiation and in the presence of [Co(NH3)5Cl]Cl2 as a sacrificial electron acceptor, both complexes exhibited good photocatalytic activity toward oxidation of sulfide into the corresponding sulfoxide with high efficiency and >99% product selectivity in neutral aqueous solution. The Ru-aqua complex assembly was more efficient than the chloro complex. Isotopic labeling experiments using (18)O-labeled water demonstrated the oxygen atom transfer from the water to the organic substrate, likely through the formation of an active intermediate, Ru(IV)═O.

Two mononuclear ruthenium complexes [Ru(H2tcbp)(isoq)2] (1) and [Ru(H2tcbp)(pic)2] (2) (H4tcbp=4,4',6,6'-tetracarboxy-2,2'-bipyridine, isoq=isoquinoline, pic=4-picoline) are synthesized and fully characterized. Two spare carboxyl groups on the 4,4'-positions are introduced to enhance the solubility of 1 and 2 in water and to simultaneously allow them to tether to the electrode surface by an ester linkage. The photochemical, electrochemical, and photoelectrochemical water oxidation performance of 1 in neutral aqueous solution is investigated. Under electrochemical conditions, water oxidation is conducted on the deposited indium-tin-oxide anode, and a turnover number higher than 15,000 per water oxidation catalyst (WOC) 1 is obtained during 10 h of electrolysis under 1.42 V vs. NHE, corresponding to a turnover frequency of 0.41 s(-1). The low overpotential (0.17 V) of electrochemical water oxidation for 1 in the homogeneous solution enables water oxidation under visible light by using [Ru(bpy)3](2+) (P1) (bpy=2,2'-bipyridine) or [Ru(bpy)2(4,4'-(COOEt)2-bpy)](2+) (P2) as a photosensitizer. In a three-component system containing 1 or 2 as a light-driven WOC, P1 or P2 as a photosensitizer, and Na2S2O8 or [CoCl(NH3)5]Cl2 as a sacrificial electron acceptor, a high turnover frequency of 0.81 s(-1) and a turnover number of up to 600 for 1 under different catalytic conditions are achieved. In a photoelectrochemical system, the WOC 1 and photosensitizer are immobilized together on the photoanode. The electrons efficiently transfer from the WOC to the photogenerated oxidizing photosensitizer, and a high photocurrent density of 85 μA cm(-2) is obtained by applying 0.3 V bias vs. NHE., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Four new charge-neutral ruthenium(II) complexes containing dianionic Schiff base and isoquinoline or 4-picoline ligands were synthesized and characterized by NMR and ESI-MS spectroscopies, elemental analysis, and X-ray diffraction. The complexes exhibited excellent chemical water oxidation activity and high stability under acidic conditions (pH 1.0) using (NH4)2Ce(NO3)6 as a sacrificial electron acceptor. The high catalytic activities of these complexes for water oxidation were sustained for more than 10 h at low concentrations. High turnover numbers of up to 3200 were achieved. A water nucleophilic attack mechanism was proposed. A Ru(V)=O intermediate was detected during the catalytic cycle by high-resolution mass spectrometry., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To purify and identify recombinant Varicella-Zoster Virus Glycoprotein E., Methods: The recombinant plasmid pGEX-VZVgE was induced by isopropyl-beta-D-thiogalactoside (IPTG), the fusion protein was purified with affinity chromatography column; then the purified fusion protein was cleaved by thrombin, and the product's antigenicity was examined by Western blot., Results: The product of pGEX-VZVgE induced by IPTG was separated from the mixture proteins by the affinity chromatography column, the expressed fusion protein's relative molecular mass was about 98 x 10(3). After cleavage, the obtained VZV Glycoprotein E's relative molecular mass was about 72 x 10(3); the purified fusion protein and VZV Glycoprotein E were single band by SDS-PAGE. The available antigenicity of Glycoprotein E was confirmed by Western blot., Conclusion: Purification of VZV Glycoprotein E with affinity chromatography is an effective method. It provides a foreground for studies on the application of VZV gE.