Search

Enhancing the durability of catalysts is of critical significance to industrialize green hydrogen production. Herein, a novel active site in situ refreshing strategy is proposed and demonstrated to fabricate highly active and ultra‐durable hydrogen evolution reaction (HER) electro‐catalytic material by HER activation. Briefly, a composite catalytic material is synthesized, which features Ni(PO3)2 active sites being embedded inside the amorphous Mo compound matrix (named NiMoO‐P). The Mo compound matrix undergoes gradual dissolution during HER followed by a dynamic equilibrium between the dissolution and deposition of the amorphous matrix. This process promotes the continuous exposure of insoluble Ni(PO3)2 and Ni2P partially converted from Ni (PO3) 2 in situ on the surface during HER activation. Thus, activated catalyst exhibits excellent HER performance featuring an extremely high current density of 1500 mA cm−2 at a rather low overpotential of 340 mV, and more attractively, an ultra‐long durability for hydrogen evolution for at least 1000 h at an industrial‐applicable current density of 900 mA cm−2. The mechanisms for the especially high HER performance are attributed to the exposure and continuous refreshing of Ni(PO3)2 and the in situ formed Ni2P during the HER process based on the DFT calculations and quasi‐in situ Raman spectroscopic monitoring. [ABSTRACT FROM AUTHOR]

Electrocatalytic glycerol oxidation reaction (GOR) is an effective way to convert biomass byproduct to high value‐added chemicals, which; however, suffers from the low oxidation activity and conversion ratio of the presently available catalysts. Herein, the NiCo2O4/NF bimetallic oxide nanoarray is controllably fabricated by Ni substituting for octahedral Co3+ in Co3O4, which exhibits excellent GOR catalytic activity at elevated current densities (E300 = 1.42 V, E600 = 1.62 V) and overall Faradaic efficiency of 97.5% at 1.42 V (FEformic acid = 89.9% and FEglycolic acid = 7.62%). The high performance is attributed to the structure evolution including the rapid generation of NiIII‐OOH and CoIII‐OOH active species, the optimized intermediates adsorption, and the accelerated electron transfer owing to the Ni introduction, which are evidenced by the operando spectroscopy measurements and density functional theory calculations, respectively. The GOR/hydrogen evolution coupled two‐electrode electrolytic cell voltage is ≈299 mV lower than that of the water splitting at 50 mA cm−2. More importantly, compared to conventional water splitting, this electrolyzer is stable for over 200 h at 1.75 V, reducing energy consumption by 16.9% and obtaining high value‐added products at the anode concurrently. [ABSTRACT FROM AUTHOR]

Objective: To determine whether surgery for adnexal masses in the first trimester of pregnancy affects subsequent pregnancy outcomes compared to surgery in the second trimester.Methods: Data were retrospectively reviewed from women who underwent adnexal mass surgery before 26 weeks of gestation at a university hospital between July 2008 and June 2018. Women who underwent surgery in the first trimester were classified as group 1 (n=78) and those in the second trimester were classified as group 2 (n=48). Information on clinical characteristics and pregnancy outcomes was obtained from medical records and follow-up interviews and compared between two groups.Results: There were no differences in age, parity, mass size, laparoscopy, and operation time between the two groups. A total of 98 cases were confirmed as ovarian torsion, including 72 cases in group 1 and 26 cases in group 2. Accordingly, adnexectomy was performed more often in group 1 (P=0.002). No significant differences concerning the rate of abortion, preterm birth, or cesarean delivery were found.Conclusion: Surgery for adnexal masses performed in the first trimester is almost as safe as that in the second trimester. Surgery should be performed for women with a complex adnexal mass in the first trimester to avoid unfavorable complications. [ABSTRACT FROM AUTHOR]

A novel Zn−Fe flow battery featuring an Fe3+ reduction reaction (Fe3+RR)‐coupled zinc oxidation, and an Fe2+ oxidation reaction (Fe2+OR)‐coupled hydrogen evolution reaction (HER) system as well, was established. This battery is capable of driving two Fe2+OR‐coupled HER systems in series based on the above Fe2+/Fe3+ cycling, for efficient self‐powered hydrogen evolution. Meanwhile, this Fe2+/Fe3+ cycling enables the preparation of a multifunctional catalyst, Pt‐3@SXNS (siloxene nanosheet), by the Fe2+OR‐promoted dispersion of Pt nanoparticles on SXNS; alternatively, this support could be obtained by Fe3+RR‐assisted exfoliation using Fe3+ from the anolyte of Fe2+OR‐coupled HER. The Pt‐3@SXNS catalyst exhibits excellent catalytic activities toward Fe3+RR in the Zn−Fe flow battery, HER, and Fe2+OR in the electrolyzer, which is attributed to the strong electronic interaction between Pt and Si. This work offers a new strategy for energy storage and low‐cost hydrogen production from acidic wastewater. [ABSTRACT FROM AUTHOR]

A novel Zn−Fe flow battery featuring an Fe3+ reduction reaction (Fe3+RR)‐coupled zinc oxidation, and an Fe2+ oxidation reaction (Fe2+OR)‐coupled hydrogen evolution reaction (HER) system as well, was established. This battery is capable of driving two Fe2+OR‐coupled HER systems in series based on the above Fe2+/Fe3+ cycling, for efficient self‐powered hydrogen evolution. Meanwhile, this Fe2+/Fe3+ cycling enables the preparation of a multifunctional catalyst, Pt‐3@SXNS (siloxene nanosheet), by the Fe2+OR‐promoted dispersion of Pt nanoparticles on SXNS; alternatively, this support could be obtained by Fe3+RR‐assisted exfoliation using Fe3+ from the anolyte of Fe2+OR‐coupled HER. The Pt‐3@SXNS catalyst exhibits excellent catalytic activities toward Fe3+RR in the Zn−Fe flow battery, HER, and Fe2+OR in the electrolyzer, which is attributed to the strong electronic interaction between Pt and Si. This work offers a new strategy for energy storage and low‐cost hydrogen production from acidic wastewater. [ABSTRACT FROM AUTHOR]

Objectives: Aseptic loosening (AL) is the most common reason of total hip arthroplasty (THA) failure and revision surgery. Osteolysis, caused by wear particles released from implant surfaces, has a vital role in AL. Although previous studies suggest that wear particles always lead to osteoblast programmed death in the process of AL, the specific mechanism remains incompletely understood and osteoblast ferroptosis maybe a new mechanism of AL. Materials and Methods: CoCrMo nanoparticles (CoNPs) were prepared to investigate the influence of ferroptosis in osteoblasts and calvaria resorption animal models. Periprosthetic osteolytic bone tissue was collected from patients who underwent AL after THA to verify osteoblast ferroptosis. Results: Our study demonstrated that CoNPs induced significant ferroptosis in osteoblasts and particles induced osteolysis (PIO) animal models. Blocking ferroptosis with specific inhibitor Ferrostatin‐1 dramatically reduced particle‐induced ferroptosis in vitro. Moreover, in osteoblasts, CoNPs significantly downregulated the expression of Nrf2 (nuclear factor erythroid 2‐related factor 2), a core element in the antioxidant response. The overexpression of Nrf2 by siKeap1 or Nrf2 activator Oltipraz obviously upregulated antioxidant response elements (AREs) and suppressed ferroptosis in osteoblasts. Furthermore, in PIO animal models, the combined utilization of Ferrostatin‐1 and Oltipraz dramatically ameliorated ferroptosis and the severity of osteolysis. Conclusions: These results indicate that CoNPs promote osteoblast ferroptosis by regulating the Nrf2‐ARE signalling pathway, which suggests a new mechanism underlying PIO and represents a potential therapeutic approach for AL. [ABSTRACT FROM AUTHOR]