The lack of high‐efficient, low‐cost, and durable bifunctional electrocatalysts that act simultaneously for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is currently ...one of the major obstacles to commercializing the electrical rechargeability of zinc–air batteries. A nanocomposite CoO‐NiO‐NiCo bifunctional electrocatalyst supported by nitrogen‐doped multiwall carbon nanotubes (NCNT/CoO‐NiO‐NiCo) exhibits excellent activity and stability for the ORR/OER in alkaline media. More importantly, real air cathodes made from the bifunctional NCNT/CoO‐NiO‐NiCo catalysts further demonstrated superior performance to state‐of‐the‐art Pt/C or Pt/C+IrO2 catalysts in primary and rechargeable zinc–air batteries.
A NiCo alloy‐based bifunctional electrocatalyst (NCNT/CoO‐NiO‐NiCo) exhibits excellent activity and stability in alkaline solutions for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). When integrated into air cathodes of primary and rechargeable zinc–air batteries, the performance of NCNT/CoO‐NiO‐NiCo is superior or comparable to Pt/C or (Pt/C+IrO2)‐based air cathodes.
Porous metal-organic-frameworks (MOFs) are attractive materials for gas storage, separations, and catalytic reactions. A challenge exists, however, on how to introduce larger pores juxtaposed with ...the inherent micropores in different forms of MOFs, which would enable new functions and applications. Here we report the formation of heterogeneous pores within MOF particles, patterns, and membranes, using a discriminate etching chemistry, called silver-catalyzed decarboxylation. The heterogeneous pores are formed, even in highly stable MOFs, without altering the original structure. A decarboxylated MOF membrane is shown to have pH-responsive switchable selectivity for the flow-assisted separation of similarly sized proteins. We envision that our method will allow the use of heterogeneous pores for massive transfer and separation of complex and large molecules, and that the capability for patterning and positioning heterogeneous MOF films on diverse substrates bodes well for various energy and electronic device applications.
Inositol pyrophosphates (PP-IPs) such as 5-diphosphoinositol pentakisphosphate (5-IP7) are inositol metabolites containing high-energy phosphoanhydride bonds. Biosynthesis of PP-IPs is mediated by ...IP6 kinases (IP6Ks) and PPIP5 kinases (PPIP5Ks), which transfer phosphate to inositol hexakisphosphate (IP6). Pleiotropic actions of PP-IPs are involved in many key biological processes, including growth, vesicular remodeling, and energy homeostasis. PP-IPs function to regulate their target proteins through allosteric interactions or protein pyrophosphorylation. This review summarizes the current understanding of how PP-IPs control mammalian cellular signaling networks in physiology and disease.
Electrocatalysts for oxygen reduction are a critical component that may dramatically enhance the performance of fuel cells and metal-air batteries, which may provide the power for future electric ...vehicles. Here we report a novel bio-inspired composite electrocatalyst, iron phthalocyanine with an axial ligand anchored on single-walled carbon nanotubes, demonstrating higher electrocatalytic activity for oxygen reduction than the state-of-the-art Pt/C catalyst as well as exceptional durability during cycling in alkaline media. Theoretical calculations suggest that the rehybridization of Fe 3d orbitals with the ligand orbitals coordinated from the axial direction results in a significant change in electronic and geometric structure, which greatly increases the rate of oxygen reduction reaction. Our results demonstrate a new strategy to rationally design inexpensive and durable electrochemical oxygen reduction catalysts for metal-air batteries and fuel cells.
Aims
To investigate anti‐inflammatory effects of Lactobacillus reuteri LM1071 in lipopolysaccharides (LPS)‐induced inflammation RAW264.7 cells.
Methods and Results
To evaluate anti‐inflammatory ...activities of L. reuteri LM1071, LPS‐stimulated RAW264.7 cells were used. Gene expression levels of eight immune‐associated genes including IL‐1β, IL‐6 and TNF‐α and protein production levels of COX‐1 and COX‐2 were analysed. Moreover, the production of eicosanoids as important biomarkers for anti‐inflammation was determined.
Conclusions
The current study demonstrates that L. reuteri LM1071 has anti‐inflammatory potential by inhibiting the production of inflammation mediators such as NO, eicosanoids such as PGE1 & PGE2, pro‐inflammatory cytokines and COX proteins. It can also enhance the production of inflammatory associated genes such as IL‐11, BMP4, LEFTY2 and EET metabolite.
Significance and Impact of the Study
Lactobacillus reuteri is one of the crucial bacteria for food fermentation. It can be found in the gastrointestinal system of human and animals. Several studies have shown that L. reuteri has valuable effects on host health. The current study firstly demonstrated that L. reuteri has a beneficial effect on the inflammation containing the variation of eicosanoids (PGE1 and PGE2) which are one of the most important biomarkers and moreover eicosanoid‐associated genes as well as proteins (COX‐2).
Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) along with hydrogen evolution reaction (HER) have been considered critical processes for electrochemical energy conversion and ...storage through metal‐air battery, fuel cell, and water electrolyzer technologies. Here, a new class of multifunctional electrocatalysts consisting of dominant metallic Ni or Co with small fraction of their oxides anchored onto nitrogen‐doped reduced graphene oxide (rGO) including Co‐CoO/N‐rGO and Ni‐NiO/N‐rGO are prepared via a pyrolysis of graphene oxide and cobalt or nickel salts. Ni‐NiO/N‐rGO shows the higher electrocatalytic activity for the OER in 0.1 m KOH with a low overpotential of 0.24 V at a current density of 10 mA cm−2, which is superior to that of the commercial IrO2. In addition, it exhibits remarkable activity for the HER, demonstrating a low overpotential of 0.16 V at a current density of 20 mA cm−2 in 1.0 m KOH. Apart from similar HER activity to the Ni‐based catalyst, Co‐CoO/N‐rGO displays the higher activity for the ORR, comparable to Pt/C in zinc‐air batteries. This work provides a new avenue for the development of multifunctional electrocatalysts with optimal catalytic activity by varying transition metals (Ni or Co) for these highly demanded electrochemical energy technologies.
A new class of multifunctional electrocatalysts, composed of Co–CoO/N–rGO and Ni–NiO/N–rGO is synthesized via a pyrolysis of graphene oxide and cobalt or nickel salts. The two catalysts show excellent activities for oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), or oxygen evolution reaction (OER). In particular Co–CoO/N–rGO shows comparable performance to Pt/C in zinc‐air batteries.
Designing a facile strategy to access active and atomically dispersed metallic catalysts are highly challenging for single atom catalysts (SACs). Herein, a simple and fast approach is demonstrated to ...construct Pt catalysts with single atoms in large quantity via ball milling Pt precursor and N‐doped carbon support (K2PtCl4@NC‐M; M denotes ball‐milling). The as‐prepared K2PtCl4@NC‐M only requires a low overpotential of 11 mV and exhibits 17‐fold enhanced mass activity for the electrochemical hydrogen evolution compared to commercial 20 wt% Pt/C. The superior hydrogen evolution reaction (HER) catalytic activity of K2PtCl4@NC‐M can be attributed to the generation of Pt single atoms, which improves the utilization efficiency of Pt atoms and the introduction of Pt‐N2C2 active sites with near‐zero hydrogen adsorption energy. This viable ball milling method is found to be universally applicable to the fabrication of other single metal atoms, for example, rhodium and ruthenium (such as Mt‐N2C2, where Mt denotes single metal atom). This strategy also provides a promising and practical avenue toward large‐scale energy storage and conversion application.
A simple and fast approach is developed to construct Pt catalysts with single atoms in large quantity via ball milling a Pt precursor and N‐doped carbon support. The as‐prepared K2PtCl4@NC‐M exhibits 17‐fold‐enhanced mass activity for hydrogen evolution compared to commercial 20 wt% Pt/C.
This study conducted a detection and attribution analysis of the observed global and regional changes in extreme temperatures during 1951–2015. HadEX3 observations were compared with multimodel ...simulations from the Coupled Model Intercomparison Project phase 6 (CMIP6) using an optimal fingerprinting technique. Annual maximum daily maximum and minimum temperatures (TXx and TNx; warm extremes) and annual minimum daily maximum and minimum temperatures (TXn and TNn; cold extremes) over land were analyzed considering global, continental, and subcontinental scales. Response patterns (fingerprints) of extreme temperatures to anthropogenic (ANT), greenhouse gases (GHG), aerosols (AA), and natural (NAT) forcings were obtained from CMIP6 forced simulations. The internal variability ranges were estimated from preindustrial control simulations. A two-signal detection analysis where the observations are regressed onto ANT and NAT fingerprints simultaneously reveals that ANT signals are robustly detected in separation from NAT over global and all continental domains (North and South America, Europe, Asia, and Oceania) for most of the extreme indices. ANT signals are also detected over many subcontinental regions, particularly for warm extremes (more than 60% of 33 subregions). A three-signal detection analysis that considers GHG, AA, and NAT fingerprints simultaneously demonstrates that GHG signals are detected in isolation from other external forcings over global, continental, and several subcontinental domains especially for warm extremes, explaining most of the observed warming. Moreover, AA influences are detected for warm extremes over Europe and Asia, indicating significant offsetting cooling contributions. Overall, human influences are detected more frequently, compared to previous studies, particularly for cold extremes, due to the extended period and the improved spatial coverage of observations.
Facilitating the dissociation of water and desorption of hydrogen are both crucial challenges for improving the hydrogen evolution reaction (HER) in alkaline media. Herein, we report the synthesis of ...heterostructure of Ru2P/WO3@NPC (N, P co‐doped carbon) by a simple hydrothermal reaction using ruthenium and tungsten salts as precursors, followed by pyrolyzing under an Ar atmosphere. The Ru2P/WO3@NPC electrocatalyst exhibits an outstanding HER activity with an overpotential of 15 mV at a current density of 10 mA cm−2 and excellent durability in a 1.0 M KOH solution, outperforming state‐of‐the‐art Pt/C and most reported electrocatalysts. Experimental results combined with density functional calculations reveal that the electron density redistribution in Ru2P/WO3@NPC is achieved by electron transfer from NPC to Ru2P/WO3 and from Ru2P to WO3, which directly promotes the dissociation of water on W sites in WO3 and desorption of hydrogen on Ru sites in Ru2P.
A heterostructure of Ru2P/WO3@NPC was designed for electrochemically producing hydrogen in alkaline electrolyte. Electron transfer from NPC to Ru2P/WO3 and from Ru2P to WO3 accelerates the dissociation of water on W sites and desorption of hydrogen on Ru sites, thus promoting hydrogen evolution.
PDF
