Enriched Fe Doped on Amorphous Shell Enable Crystalline@Amorphous Core-Shell Nanorod Highly Efficient Electrochemical Water Oxidation.

The rational design of efficient and cost-effective electrocatalysts for oxygen evolution reaction (OER) with sluggish kinetics, is imperative to diverse clean energy technologies. The performance of electrocatalyst is usually governed by the number of active sites on the surface. Crystalline/amorphous heterostructure has exhibited unique properties and opens new paradigms toward designing electrocatalysts with abundant active sites for improved performance. Hence, Fe doped Ni-Co phosphite (Fe-NiCoHPi) electrocatalyst with cauliflower-like structure, comprising crystalline@amorphous core-shell nanorod, is reported. The experiments uncover that Fe is enriched in the amorphous shell due to the flexibility of the amorphous component. Further density functional theory calculations indicate that the strong electronic interaction between the enriched Fe in the amorphous shell and crystalline core host at the core-shell interface, leads to balanced binding energies of OER intermediates, which is the origin of the catalyst-activity. Eventually, the Fe-NiCoHPi exhibits remarkable activity, with low overpotentials of only 206 and 257 mV at current density of 15 and 100 mA cm-2 . Unceasing durability over 90 h is achieved, which is superior to the effective phosphate electrocatalysts. Although the applications at high current remain challenges , this work provides an approach for designing advanced OER electrocatalysts for sustainable energy devices.

Ultra-Low Pt Doping and Pt-Ni Pair Sites in Amorphous/Crystalline Interfacial Electrocatalyst Enable Efficient Alkaline Hydrogen Evolution.

Noble metal doping can achieve an increase in mass activity (MA) without sacrificing catalysis efficiency and stability, so that alkaline hydrogen evolution reaction (HER) performance of the catalyst can be optimized to the maximum degree. However, its excessively large ionic radius makes it difficult to achieve either interstitial doping or substitutional doping under mild conditions. Herein, a hierarchical nanostructured electrocatalyst with enriched amorphous/crystalline interfaces for high-efficiency alkaline HER is reported, which is composed of amorphous/crystalline (Co, Ni)11 (HPO3 )8 (OH)6 homogeneous hierarchical structure with an ultra-low doped Pt (Pt-a/c-NiHPi). Benefiting from the structural flexibility of the amorphous component, extremely low Pt (0.21 wt.%, totally 3.31 µg Pt on 1 cm-2 NF) are stably doped on it via a simple two-phase hydrothermal method. The DFT calculations show that due to the strongly electron transfer between the crystalline/amorphous components at the interfaces, electrons finally concentrate toward Pt and Ni in the amorphous components, thus the electrocatalyst has near-optimal energy barriers and adsorption energy for H2 O* and H* . With the above benefits, the obtained catalyst exhibits an exceptionally high MA (39.1 mA µg-1 Pt ) at 70 mV, which is almost the highest level among the reported Pt-based electrocatalysts for alkaline HER.

Multiple roles for LaFeO3 in enhancing the Photoelectrochemical performance of WO3.

For photoelectrochemical (PEC) water splitting, constructing heterojunctions and loading co-catalysts are effective means to realizing sufficient light absorption, effective photogenerated carrier separation and fast charge transport. However, during implementation, the PEC performance of the catalyst is affected by both parasitic light absorption and reflection and the change in energy band structure due to the creation of new interfaces. Herein, in order to minimize the effect of recombination of photogenerated electron-hole pairs on the catalyst PEC performance due to the nascent interface arising from the co-catalyst compounding, WO3 and Ni/Co co-doped LaFeO3 (LFO) are constructed as heterojunctions, in which NiCo-LFO acts both as a part of the heterojunction to enhance photogenerated carrier separation and a co-catalyst to enhance the conductivity and modulate the surface state density at the catalyst-electrolyte interface. The current density of NiCo-LFO/WO3 reaches 3.92 mA cm-2, which is more than 7 times that of LFO/WO3. This work provides a reference for the efficient water splitting of B-site doped, especially the co-doped perovskite oxide as multifunctional roles integrated with conventional photoelectrodes.

Interfacial Engineering of Polycrystalline Pt5 P2 Nanocrystals and Amorphous Nickel Phosphate Nanorods for Electrocatalytic Alkaline Hydrogen Evolution.

Electrocatalytic hydrogen evolution reaction (HER) in alkaline media is important for hydrogen economy but suffers from sluggish reaction kinetics due to a large water dissociation energy barrier. Herein, Pt5 P2 nanocrystals anchoring on amorphous nickel phosphate nanorods as a high-performance interfacial electrocatalyst system (Pt5 P2 NCs/a-NiPi) for the alkaline HER are demonstrated. At the unique polycrystalline/amorphous interface with abundant defects, strong electronic interaction, and optimized intermediate adsorption strength, water dissociation is accelerated over abundant oxophilic Ni sites of amorphous NiPi, while hydride coupling is promoted on the adjacent electron-rich Pt sites of Pt5 P2 . Meanwhile, the ultra-small-sized Pt5 P2 nanocrystals and amorphous NiPi nanorods maximize the density of interfacial active sites for the Volmer-Tafel reaction. Pt5 P2 NCs/a-NiPi exhibits small overpotentials of merely 9 and 41 mV at -10 and -100 mA cm-2 in 1 M KOH, respectively. Notably, Pt5 P2 NCs/a-NiPi exhibits an unprecedentedly high mass activity (MA) of 14.9 mA µgPt -1 at an overpotential of 70 mV, which is 80 times higher than that of Pt/C and represents the highest MA of reported Pt-based electrocatalysts for the alkaline HER. This work demonstrates a phosphorization and interfacing strategy for promoting Pt utilization and in-depth mechanistic insights for the alkaline HER.

Death among children under five years of age in Huzhou City from 2012 to 2021 / 预防医学

Objective@# To analyze the death among children under 5 years of age in Huzhou City, Zhejiang Province from 2012 and 2021, so as to provide insights into reduction of mortality among children. @*Methods@#The mortality surveillance data among children under 5 years of age in Huzhou City from 2012 to 2021 were collected from Children Death Report Cards and Surveillance Report among Children under 5 Years of Age, including gender, place of residence, date of death and death diagnosis. The trends in mortality and cause of death were analyzed among children under 5 years of age in Huzhou City from 2012 to 2021.@*Results@#A total of 1 262 deaths occurred among children under 5 years of age in Huzhou City from 2012 to 2021, with mean annual mortality of 4.39‰, and the mortality appeared a tendency towards a decline (χ2trend=132.695, P<0.001). A total of 899 infants died, with mean annual mortality of 3.13‰, and 363 children at ages of 1 to <5 years died, with mean annual mortality of 1.26‰. The mortality appeared a tendency towards a decline among both infants (χ2trend=117.778, P<0.001) and children at ages of 1 to <5 years (χ2trend=19.201, P<0.001). A total of 724 local children died, with mean annual mortality of 3.33‰, and there were 538 deaths among floating children, with mean annual mortality of 7.65‰. The mortality appeared a tendency towards a decline among both local (χ2trend=43.728, P<0.001) and floating children (χ2trend=94.038, P<0.001). The five most common causes of death included preterm birth or low birth weight (207 deaths, 16.40%), drowning (155 deaths, 12.28%), accidental asphyxia (138 deaths, 10.94%), other congenital abnormalities (126 deaths, 9.98%), and congenital heart diseases (113 deaths, 8.95%). @*Conclusions @#The mortality appeared a tendency towards a decline among children under 5 years of age in Huzhou City from 2012 to 2021, and preterm birth or low birth weight was the predominant cause of death.

Meta-analysis of the effects of Bifidobacterium preparations for the prevention and treatment of pediatric antibiotic-associated diarrhea in China.

Bifidobacterium preparations are increasingly used for pediatric antibiotic-associated diarrhea (AAD) in China. The aim of this study was to review existing evidence on the efficacy of Bifidobacterium preparations for the prevention and treatment of pediatric AAD in China. Searches were performed with Medline, Embase, Cochrane Central Register of Controlled Trials, CNKI, and CBM databases. Thirty trials met the inclusion criteria. Of the 30 trials, five Bifidobacterium preparations were included. The preparations were all Bifidobacterium based, in combined with Lactobacillus, Enterococcus, Bacillus, Streptococcus or Clostridium strains. The pooled results of the 30 trials, which included 7225 participants, indicated a statistically significant association of Bifidobacterium preparations administration with reduction in pediatric AAD (odds ratio [OR], 0.33; 95% confidence interval [CI], 0.29-0.39; P<0.01). When the meta-analysis was re-performed according to the trials explicitly aiming to prevent or treat pediatric AAD, respectively, the pooled results were similar (Bifidobacterium preparations use for preventing pediatric AAD (n=21): pooled OR, 0.34, 95% CI, 0.28-0.41, P<0.01; Bifidobacterium preparations use for treating pediatric AAD (n=9): pooled OR, 0.32, 95% CI, 0.23-0.43, P<0.01). Subgroup analyses which based on Bifidobacterium preparations variety, clinical condition, or participant's age also showed statistically significant benefit of adjunct Bifidobacterium preparations for the prevention and treatment of pediatric AAD in China. The pooled evidence suggested that Bifidobacterium preparations might be efficacious for the prevention and treatment of pediatric AAD in China.