Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern ...globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans.
We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed.
Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown β-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor.
A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.
With growing demand for propylene and increasing production of propane from shale gas, the technologies of propylene production, including direct dehydrogenation and oxidative dehydrogenation of ...propane, have drawn great attention in recent years. In particular, direct dehydrogenation of propane to propylene is regarded as one of the most promising methods of propylene production because it is an on-purpose technique that exclusively yields propylene instead of a mixture of products. In this critical review, we provide the current investigations on the heterogeneous catalysts (such as Pt, CrOx, VOx, GaOx-based catalysts, and nanocarbons) used in the direct dehydrogenation of propane to propylene. A detailed comparison and discussion of the active sites, catalytic mechanisms, influencing factors (such as the structures, dispersions, and reducibilities of the catalysts and promoters), and supports for different types of catalysts is presented. Furthermore, rational designs and preparation of high-performance catalysts for propane dehydrogenation are proposed and discussed.
This review presents the state-of-the-art catalysts (including Pt, CrOx, VOx, GaOx, ZnO, FeOx, CoOx, SnOx, ZrO2-based catalysts, and nanocarbons) that have been reported in recent years for direct dehydrogenation of propane to propylene.
Developing cost‐efficient multifunctional electrocatalysts is highly critical for the integrated electrochemical energy‐conversion systems such as water electrolysis based on hydrogen/oxygen ...evolution reactions (HER/OER) and metal‐air batteries based on OER/oxygen reduction reactions (ORR). The core–shell structured materials with transition metal phosphide as the core and nitrogen‐doped carbon (NC) as the shell have been known as promising HER electrocatalysts. However, their oxygen‐related electrocatalytic activities still remain unsatisfactory, which severely limits their further applications. Herein an effective strategy to improve the core and shell performances of core–shell Co2P@NC electrocatalysts through secondary metal (e.g., Fe, Ni, Mo, Al, Mn) doping (termed M‐Co2P@M‐N‐C) is reported. The as‐synthesized M‐Co2P@M‐N‐C electrocatalysts show multifunctional HER/OER/ORR activities and good integrated capabilities for overall water splitting and Zn‐air batteries. Among the M‐Co2P@M‐N‐C catalysts, Fe‐Co2P@Fe‐N‐C electrocatalyst exhibits the best catalytic activities, which is closely related to the configuration of highly active species (Fe‐doping Co2P core and Fe‐N‐C shell) and their subtle synergy, and a stable carbon shell for outstanding durability. Combination of electrochemical‐based in situ Fourier transform infrared spectroscopy with extensive experimental investigation provides deep insights into the origin of the activity and the underlying electrocatalytic mechanisms at the molecular level.
By incorporating various secondary metals (e.g., Fe, Ni, Mo, Mn, and Al) into core–shell Co2P@NC system, the trifunctional catalytic activities of core and shell of Co2P@NC toward HER/OER/ORR is enhanced simultaneously, leading to an advanced catalytic system (Fe‐Co2P@Fe‐N‐C) with high catalytic efficiency and remarkable stability for efficient water electrolysis and rechargeable liquid/all‐solid‐state Zn‐air batteries.
Small ZnO nanoclusters supported on dealuminated β zeolite were prepared and evaluated for catalyzing direct dehydrogenation of propane to propylene (PDH), exhibiting high catalytic performance. N2 ...sorption, XRD, TEM, 27Al and 28Si MAS NMR, IR, XRF, DR UV‐vis, XPS, and NH3‐TPD techniques were employed to characterize the physicochemical properties of this novel catalyst system. It is found that the Zn species can be accommodated in the vacant T‐atom sites of dealuminated β zeolite due to the reaction of aqueous zinc acetate solution with silanol groups, and thus, producing massive small ZnO nanoclusters as active phases in PDH. Additionally, dealuminated β zeolite can greatly depress side reactions attributable to the absence of strong acid sites, thereby guaranteeing high catalytic activity, propylene selectivity and stability. As a result, the optimal catalyst of 10 wt% Zn loaded on dealuminated β zeolite exhibits a high initial propane conversion of around 53 % and a superior propylene selectivity of about 93 % at a space velocity of 4000 cm3 gcat−1 h−1, together with the high stability and satisfactory reusability. This study may open a new way to design and synthesize highly active PDH catalysts with high selectivity and stability.
Catalysts with Zing: Small ZnO nanoclusters supported on dealuminated β zeolite can be obtained via a two‐step post‐synthesis method, showing much better catalytic performance for direct dehydrogenation of propane to propylene than that on raw Hβ zeolite.
A small amount of Co (0.5 wt%) supported on dealuminated Beta zeolite shows much better catalytic performance than other Co catalysts. The small confined metallic Co serving as the active site is ...proposed.
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•CoSiBeta catalysts have state-of-the-art productivity for direct dehydrogenation of propane.•CoSiBeta catalysts with or without prereduction show similar catalytic performance.•The CoOx species confined in the silanols of SiBeta can be reduced to small metallic Co particles.•The confined small metallic Co particles are catalytically active for PDH.
CoOx within dealuminated Beta (SiBeta) zeolite developing into ultrasmall-sized Co particles under H2 or reactant gas is highly efficient for catalyzing direct dehydrogenation of propane (PDH) to propylene reaction. The existence of highly dispersed CoOx species is identified, and the easily reducible CoOx species are confined in the created T-sites (silanols) of SiBeta support. The CoSiBeta catalysts with or without prereduction treatments show similar catalytic performance but different induction periods, implying that the metallic Co formed in situ during the reaction are the active sites. Co in SiBeta zeolite (0.5 wt%) showed state-of-the-art propylene productivity with propane conversion of about 72% and propylene selectivity of over 92% at 600 °C, which is far better than that of the other reported Co catalysts and comparable to that of industrial catalysts. This work proves the high catalytic ability and product selectivity of small confined Co particles, as well as providing novel inspiration for the design of low-cost, ecofriendly, and advanced catalysts for PDH.
Well-dispersed and ultrasmall PtZn bimetallic nanoclusters encapsulated in Silicalite-1 zeolites are prepared via a facile in situ synthetic strategy, showing excellent catalytic performance for ...propane dehydrogenation to propene.
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•Ultrasmall PtZn bimetallic clusters within S-1 were prepared by an in situ synthetic route.•PtZn@S-1 shows excellent catalytic performance and high stability for PDH.•The smaller Pt-containing clusters have higher dehydrogenation activity.•The confinement effect of zeolites improves the stability of the metal clusters.•Zeolite-confined nanocatalysts also show excellent shape-selective activity.
Bimetallic catalysts have attracted increasing attention in propane dehydrogenation (PDH) due to the synergistic effect of metal species and considerably improved catalytic performance, but they often suffer from severe sintering and poor stability. Here, well-dispersed and ultrasmall PtZn bimetallic nanoclusters encapsulated in silicalite-1 (S-1) zeolites (named PtZn@S-1) are prepared via a facile in situ synthesis strategy. It is indicated that the PtZn bimetallic nanoclusters with ultrasmall size are homogeneously dispersed within the channels of S-1 zeolites. The 0.3Pt0.5Zn@S-1 catalyst shows excellent catalytic performance in PDH with a propane conversion of 45.3% and a propylene selectivity of >99%, and no visible sintering of PtZn bimetallic nanoclusters is observed in the long-term PDH reaction at 550 °C. The excellent catalytic properties and high stability of the ultrasmall bimetallic nanoclusters confined in zeolites create new prospects for PDH.
Versatile electrocatalysis at higher current densities for natural seawater splitting to produce hydrogen demands active and robust catalysts to overcome the severe chloride corrosion, competing ...chlorine evolution, and catalyst poisoning. Hereto, the core‐shell‐structured heterostructures composed of amorphous NiFe hydroxide layer capped Ni3S2 nanopyramids which are directly grown on nickel foam skeleton (NiS@LDH/NF) are rationally prepared to regulate cooperatively electronic structure and mass transport for boosting oxygen evolution reaction (OER) performance at larger current densities. The prepared NiS@LDH/NF delivers the anodic current density of 1000 mA cm−2 at the overpotential of 341 mV in 1.0 m KOH seawater. The feasible surface reconstruction of Ni3S2‐FeNi LDH interfaces improves the chemical stability and corrosion resistance, ensuring the robust electrocatalytic activity in seawater electrolytes for continuous and stable oxygen evolution without any hypochlorite production. Meanwhile, the designed Ni3S2 nanopyramids coated with FeNi2P layer (NiS@FeNiP/NF) still exhibit the improved hydrogen evolution reaction (HER) activity in 1.0 m KOH seawater. Furthermore, the NiS@FeNiP/NF||NiS@LDH/NF pair requires cell voltage of 1.636 V to attain 100 mA cm−2 with a 100% Faradaic efficiency, exhibiting tremendous potential for hydrogen production from seawater.
Herein, core‐shell structured Ni3S2‐FeNi layer double hydroxides (LDH) heterointerfaces are rationally prepared. Abundant hydroxide/sulfide interfaces boost alkaline water oxidation. Impressively, electrochemical results indicate that the in situ formed sulfate layer in LDH shell largely enhances the corrosion resistance of the catalysts in the alkaline salty‐water electrolytes.
Skin damages are defined as one of most common lesions people suffer from, some of wounds are notoriously difficult to eradicate such as chronic wounds and deep burns. Existing wound therapies have ...been proved to be inadequate and far from satisfactory. The cutting-edge nanotechnology offers an unprecedented opportunity to revolutionize and invent new therapies or boost the effectiveness of current medical treatments. In particular, the nano-drug delivery systems anchor bioactive molecules to applied area, sustain the drug release and explicitly enhance the therapeutic efficacies of drugs, thus making a fine figure in field relevant to skin regeneration. This review summarized and discussed the current nano-drug delivery systems holding pivotal potential for wound healing and skin regeneration, with a special emphasis on liposomes, polymeric nanoparticles, inorganic nanoparticles, lipid nanoparticles, nanofibrous structures and nanohydrogel.
Rechargeable zinc–air batteries (Re‐ZABs) are one of the most promising next‐generation batteries that can hold more energy while being cost‐effective and safer than existing devices. Nevertheless, ...zinc dendrites, non‐portability, and limited charge–discharge cycles have long been obstacles to the commercialization of Re‐ZABs. Over the past 30 years, milestone breakthroughs have been made in technical indicators (safety, high energy density, and long battery life), battery components (air cathode, zinc anode, and gas diffusion layer), and battery configurations (flexibility and portability), however, a comprehensive review on advanced design strategies for Re‐ZABs system from multiple angles is still lacking. This review underscores the progress and strategies proposed so far to pursuit the high‐efficiency Re‐ZABs system, including the aspects of rechargeability (from primary to rechargeable), air cathode (from unifunctional to bifunctional), zinc anode (from dendritic to stable), electrolytes (from aqueous to non‐aqueous), battery configurations (from non‐portable to portable), and industrialization progress (from laboratorial to practical). Critical appraisals of the advanced modification approaches (such as surface/interface modulation, nanoconfinement catalysis, defect electrochemistry, synergistic electrocatalysis, etc.) are highlighted for cost‐effective flexible Re‐ZABs with good sustainability and high energy density. Finally, insights are further rendered properly for the future research directions of advanced zinc–air batteries.
Rechargeable zinc–air batteries are of great significance among metal‐air battery chemistries. However, their commercialization still has a long way to go due to unresolved shortcomings such as zinc dendrites, non‐portability, low cycle performance, and so on. Advanced and practical strategies to tackle these challenges are systematically summarized from multiple angles: rechargeability, air cathodes, zinc anodes, electrolytes, and battery configurations, aiming to provide some value guidance for the rapid development of zinc–air batteries.
Efficient bifunctional hydrogen electrocatalysis, encompassing both hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR), is of paramount significance in advancing hydrogen‐based ...societies. While non‐precious‐metal‐based catalysts, particularly those based on nickel (Ni), are essential for alkaline HER/HOR, their intrinsic catalytic activity often falls short of expectations. Herein, an internal electric field (IEF) strategy is introduced for the engineering of heterogeneous nickel‐vanadium oxide nanosheet arrays grown on porous nickel foam (Ni‐V2O3/PNF) as bifunctional electrocatalysts for hydrogen electrocatalysis. Strikingly, the Ni‐V2O3/PNF delivers 10 mA cm−2 at an overpotential of 54 mV for HER and a mass‐specific kinetic current of 19.3 A g−1 at an overpotential of 50 mV for HOR, placing it on par with the benchmark 20% Pt/C, while exhibiting enhanced stability in alkaline electrolytes. Density functional theory calculations, in conjunction with experimental characterizations, unveil that the interface IEF effect fosters asymmetrical charge distributions, which results in more thermoneutral hydrogen adsorption Gibbs free energy on the electron‐deficient Ni side, thus elevating the overall efficiency of both HER and HOR. The discoveries reported herein guidance are provided for further understanding and designing efficient non‐precious‐metal‐based electrocatalysts through the IEF strategy.
A robust internal electric field has been effectively engineered to induce an asymmetrical charge distribution on the Ni‐V2O3 heterostructure, wherein the negative charge enriched V2O3 side facilitates the dissociation of water molecules, while the positively charged Ni side optimizes the H* adsorption, thus ensuring the excellent HER and HOR performance in alkaline electrolyte.
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