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Developing high-performing and cost-effective bifunctional electrocatalysts under the industrial conditions is significant for revolutionizing the hydrogen economy. Herein, we developed a bifunctional 3D-on-2D FeCo/Ni(OH) 2 hierarchical nanocatalyst on Ni mesh by a facile and low-cost method that can boost both the two half-reactions of water splitting all at once. The FeCo/Ni(OH) 2 /Ni mesh showed an outstanding electrocatalytic performance under the industrial conditions (3 M KOH, 90 °C) with applied voltages of 1.47 and 1.91 V to drive the electrolyzer at 10 and 500 mA/cm2, respectively, much better than the Ni(OH) 2 /Ni mesh, FeCo/Ni mesh, and Raney Ni/Ni mesh samples. Furthermore, it can maintain good stability for more than 192 h under the working condition of 500 mA/cm2. This promotion in electrocatalytic properties can be ascribed to the synergistic effects between 3D FeCo nanoparticles and 2D Ni(OH) 2 nanosheets, including the large electrochemically active surface areas, the intense electronic interplay between the two component and the elevated interfacial contact and charge transport. Eventually, this water electrolyzer yields a 14.7% solar-to-hydrogen efficiency when integrated with Si solar cells, which exceeds analogous solar-driven systems reported so far. The 3D-on-2D FeCo/Ni(OH) 2 hierarchical nanocatalyst on Ni mesh as a high-performing and cost-effective bifunctional catalyst for overall water splitting under the industrial conditions. [Display omitted] • A 3D-on-2D FeCo/Ni(OH) 2 hierarchical nanocatalyst on Ni mesh is well developed. • The FeCo/Ni(OH) 2 /Ni mesh showed an outstanding electrocatalytic performance. • The electrocatalytic performance attributes to the synergistic effects between two components. • A high solar-to-hydrogen efficiency of 14.7% outperforms the analogous systems. [ABSTRACT FROM AUTHOR]

• Enhanced RCAs as a novel bacteria carrier on crack-healing in concrete was studied. • Enhanced RCAs exerted equal effect on crack-healing capacity of concrete to ceramiste. • Microstructures of precipitations on RCAs and inside concrete cracks were analyzed. • Practical and cost-effective characteristics exhibited for proposed bacteria carrier. Immobilization is used to protect incorporated bacteria to maintain its high efficiency on the microbially induced carbonate precipitation (MICP) capacity in self-healing concrete over a period of time. However, several unfavorable characteristics of current bacterial carriers, such as poor compatibility with the cementitious matrix, relatively high cost, and potential decrease in mechanical properties of concrete, may limit their potential implementation in reinforced concrete (RC) construction. The objective of this study was to demonstrate the feasibility of microbial consortia-enhanced recycled concrete aggregates (RCAs), immobilizing bacteria to form self-healing cracks. The effectiveness of two other immobilization techniques (RCAs and ceramsite particle-immobilized bacteria) on the self-healing efficiency of concrete was also investigated. Experimental results showed that the physical and mechanical properties of RCAs could be markedly enhanced with extension of the biodeposition enhancement time. Concrete specimens incorporated with enhanced RCA-immobilized mixed cultures exhibited a 0.47-mm-wide crack that healed after 56 days of curing, which was equal to the 0.48-mm-wide crack that healed for specimens with ceramsite particle-immobilized mixed cultures. Mineral precipitations at the crack surfaces of self-healing concrete were calcite crystals and had regular cubic shapes. Results from this study provide a promising potential of mixed culture-enhanced RCAs for a wide range of engineering applications. [ABSTRACT FROM AUTHOR]

• Enhanced RCAs as a novel bacteria carrier on crack-healing in concrete was studied. • Enhanced RCAs exerted equal effect on crack-healing capacity of concrete to ceramiste. • Microstructures of precipitations on RCAs and inside concrete cracks were analyzed. • Practical and cost-effective characteristics exhibited for proposed bacteria carrier. Immobilization is used to protect incorporated bacteria to maintain its high efficiency on the microbially induced carbonate precipitation (MICP) capacity in self-healing concrete over a period of time. However, several unfavorable characteristics of current bacterial carriers, such as poor compatibility with the cementitious matrix, relatively high cost, and potential decrease in mechanical properties of concrete, may limit their potential implementation in reinforced concrete (RC) construction. The objective of this study was to demonstrate the feasibility of microbial consortia-enhanced recycled concrete aggregates (RCAs), immobilizing bacteria to form self-healing cracks. The effectiveness of two other immobilization techniques (RCAs and ceramsite particle-immobilized bacteria) on the self-healing efficiency of concrete was also investigated. Experimental results showed that the physical and mechanical properties of RCAs could be markedly enhanced with extension of the biodeposition enhancement time. Concrete specimens incorporated with enhanced RCA-immobilized mixed cultures exhibited a 0.47-mm-wide crack that healed after 56 days of curing, which was equal to the 0.48-mm-wide crack that healed for specimens with ceramsite particle-immobilized mixed cultures. Mineral precipitations at the crack surfaces of self-healing concrete were calcite crystals and had regular cubic shapes. Results from this study provide a promising potential of mixed culture-enhanced RCAs for a wide range of engineering applications. [ABSTRACT FROM AUTHOR]

Significant breakthroughs have recently been made in boosting the hydrogen evolution reaction (HER) of Pt-containing electrocatalysts; however, it is unclear whether they can withstand long-term operational durability under the harsh industrial conditions, especially when driven by intermittent renewable energy. Here, a Pt-containing cathode was prepared by brushing a Pt–Ni solution onto Ni mesh (NM) (denoted as Pt–Ni/NM) and paired with a NM anode to study its stability under simulated industrial conditions (30 wt. % KOH, 60 °C). The assembled electrolyzer shows superior performance of water splitting, operating constantly under ∼500 mA/cm2 when the cell voltage is kept at 1.71 V. Unfortunately, the HER activity of the cathode degrades obviously when the cell voltage is under the "on/off" (1.71 V/0 V) states when simulating the supply of intermittent renewable energy. Comprehensive analyses revealed that the decline was attributed to the galvanic corrosion owing to the difference in redox potential between Ni and Pt. When the applied protective voltage on the "off" state exceeds such potential (∼0.58 V), the corrosion can be effectively alleviated, extending the stability to over 400 h. Furthermore, this protective strategy also shows effectiveness in improving the stability of other systems (e.g., Co–Ni), offering a promising way for practical applications in industrial alkaline water electrolysis. [ABSTRACT FROM AUTHOR]

A bifunctional NiMoFe/Cu NW core–shell catalyst assembled into a practical solar-driven overall water splitting system leads to an unprecedented solar-to-hydrogen (STH) efficiency of 10.99% in neutral electrolytes, attributed to the synergic combination of a unique 3D self-supported core–shell architecture and rapid electron/mass transfer properties. [ABSTRACT FROM AUTHOR]

H9N2 virus has become the most widespread subtype of avian influenza in Chinese poultry. Although many studies have been published on this disease, the pathogenesis of the H9N2 virus remains to be fully understood. In our previous work, we identified 44 viral strains with 67–76 amino acid deletions in the neuraminidase protein (NA ∆67–76) from trachea and lung tissues after 20 successive generations in vaccinated chickens. Interestingly, these 10 amino acid deletions are located in the stalk of the NA protein, and all mutations were unique to the viruses under the selection pressure of vaccine antibodies. To investigate the effect of NA ∆67–76 on the H9N2 virus, the NA ∆67–76 deletion mutant (rF/NA Δ67–76) was constructed in the H9N2 virus A/Chicken/Shanghai/F/98 (F/98) to assess the phenotypic changes between the parental and mutant strains. The results showed that the recombinant virus rF/NA Δ67–76 had no significantly effect on the antigenicity of the virus or on the infectivity of the host cells, but it significantly inhibited the release of virions from host cells. In addition, rF/NA Δ67–76 efficiently enhanced the neuraminidase activity and improved the receptor binding ability of the virus, indicating that the influence of receptor binding ability on the rF/NA Δ67–76 virus is much greater than that of neuraminidase activity. Furthermore, this study revealed that rF/NA Δ67–76 reduced the viral replication ability at 6 and 12 h post-infection, but improved it at 24, 48, and 72 h post-infection. Chicken experiments showed that rF/NA Δ67–76 exhibits a much higher tissue tropism for the trachea rather than lung tissue. rF/NA Δ67–76 still had the ability to infect the upper respiratory tract through aerosol, but its cloaca replication capacity was significantly reduced. Both in vivo and in vitro experiments confirmed that rF/NA Δ67–76 could produce a stronger innate immune response after infecting cells and chickens, especially significantly enhancing the transcription levels of TLR3, TLR4, TLR7, TLR21, MDA5, and NLRP3. Altogether, the results of this study propose that antibody selection pressure plays an important role in the evolution of H9N2 avian influenza virus. • Deletion of 67-76 amino acids in NA protein were unique to the viruses with the selection pressure of vaccine antibodies. • rF/NA Δ67-76 efficiently enhanced the neuraminidase activity and improved the receptor binding avidity. • rF/NA Δ67-76 exhibits a much higher tissue tropism for trachea rather than lung tissue. • rF/NA Δ67-76 still had the ability to infect the trachea by aerosol, but its cloaca replication capacity was reduced. • rF/NA Δ67-76 could produce stronger innate immune response after infecting cells and chickens. [ABSTRACT FROM AUTHOR]