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Metal-based nanozymes with exceptional physicochemical property and intrinsic enzymatic properties have been widely used in industrial, medical, and diagnostic fields. However, low substrate affinity results in unsatisfying catalytic kinetic and instability in complicated conditions, which significantly decreases their sensitivity and reliability. Herein, an amorphous hollow manganese silicate nanosphere (defined as AHMS) has been successfully synthesized via a facile one-step hydrothermal method and utilized in the archetype for colorimetric detection of biothiols with high sensitivity and high reliability. The experimental data demonstrates that ultrafast affinity of the substrate contributes to enhanced sensitivity with outstanding catalytic kinetic features (Km = 27.1 μM) and low limit of detection (LODGSH = 20 nM). The designed sensor demonstrates a reliable applicability for analysis of biological liquids (fetal calf serum and Staphylococcus aureus) and design of visual logic gates. Therefore, AHMS provides a promising strategy for ultrasensitive and high-reliable biosensing. [ABSTRACT FROM AUTHOR]

[Display omitted] • The MnSiO 3 oxidase was synthesized via a facile and cost-effective route. • The supersensitivity is attributed to its excellent catalytic oxidase kinetic. • MnSiO 3 oxidase exhibits high reliability with stable enzymatic curve platform. • The MnSiO 3 oxidase is practicable for specific analysis of biological fluids. Over the past decades, advanced nanomaterial mediated intrinsic enzymatic colorimetric biosensing has been widely explored in assays and diagnostics. However, low affinity towards substrate and unstable detected curve platform leads to unsatisfactory catalytic kinetic and weak ability to eliminate the interference from difference of individual operation time, significantly decreases their sensitivity and reliability. To our best knowledge, no enzymatic colorimetric detection nanoagents have been reported to have ultrafast catalytic kinetic and stable enzymatic curve platform with satisfactory and reliable accuracy. Herein, a MnSiO 3 oxidase mimic was first reported with supersensitivity and high reliability in the paradigm for colorimetric detection of biothiols. The experiment results reveal that the supersensitivity is attributed to its ultrafast affinity towards substrate mediated an excellent catalytic kinetic (K m = 17 μM) and superior limit of detection (10 nM for GSH), which is superior to the previously reported methods. The presence of SiO 3 2− ions further improves the stability of oxidized substrate, provides a stable detected curve platform (∼10 min) and finally exhibits a high reliable accuracy whether addition of test samples at any timepoint within 10 min, which could eliminate the interference of individual operation time. In addition, MnSiO 3 is practicable for specific analysis of biological fluids (fetal calf serum and cancer cellula) and design of visual logic gates. Hence, this MnSiO 3 oxidase provides a promising solution for biosensing with super-sensitivity and high reliability. [ABSTRACT FROM AUTHOR]

Efficient energy storage systems impact profoundly the renewable energy future. The performance of current electrical energy storage technologies falls well short of requirements for using electrical energy efficiently in transportation, commercial, and residential applications. This paper explores the possibility by using transition-metal-based complexes as active materials in a Li-ion battery full cell that synergizes the concept of both lithium-ion batteries and redox flow batteries. A cathode made from transition metal complex, [Fe(bpy)3](BF4)2, exhibits high discharge voltage approaching 4 V (vs Li/Li+). When coupled with a Li4Ti5O12 anode, the Li-ion full battery exhibits a cell voltage exceeding 2.2 V and decent cycling efficiencies with Coulombic efficiency and energy/voltage efficiencies above 99% and 92%/93%, respectively. Such a Li-ion battery full cell offers distinct features such as low cost and flexibility in molecular structure design. The result reveals a generic design route toward iron-based complexes as cathode materials with good electrochemical performances. [ABSTRACT FROM AUTHOR]

[Display omitted] • Redox-active binary eutectics with weak intermolecular interaction are synthesized. • Weakening intermolecular interaction leads to enhanced ionic conductivity. • The binary eutectic alone can be used as electrolyte that show good reversibility. Eutectics are emerging as promising candidate for electrochemical energy storage. However, the eutectics usually show high viscosity that usually arises from strong intermolecular interactions greatly limits their application. In this communication, we design and prepare two redox-active molecules that both are able to form binary eutectics with TBMA-TFSI. Combined experimental and computational studies indicate the intermolecular interaction is weakened after eutectic formation, resulting in decreased viscosity and enhanced ionization ratio of TBMA-TFSI without affecting the redox behaviors of the individual molecules. Further, the redox-active binary eutectic is used as solvent-free electrolyte for battery application. [ABSTRACT FROM AUTHOR]

High-performance H 2 gas sensors based on monolayer 2D metal oxide α -MoO 3 doped with Pt/Rh has been predicted. With a binding energy of − 5.262 eV/ − 5.877 eV, the substitutional doping of Pt/Rh for Mo is a stable doping. After adsorbing O 2 in air, the band gap of Pt/Rh- α -MoO 3 decreases by 0.62 eV/0.51 eV due to the appearance of the impurity levels and the band narrowing effect. Due to such large decrease, electrons in the valence band can be excited more easily into the conduction band to produce more O 2 (a d s) − , which would oxidize more H 2 to generate H 2 O or hydroxyl along with releasing more electrons to the sensor and increasing the sensor's sensitivity. First losing electrons through adsorbing O 2 molecules in air and then obtaining electrons through adsorbing H 2 molecules in H 2 , the charge variation of the sensor based on monolayer Pt/Rh- α -MoO 3 is 1.487 e/0.394 e for per O 2 /H 2 , which suggests that the sensor may have higher sensitivity and lower detection limit. The larger charge variation is also confirmed by the shift of the Fermi level towards the higher energy direction after adsorbing H 2. • The band gap of Pt/Rh- α -MoO 3 decreases by 0.62 eV/0.51 eV after adsorbing O 2 in air. • First in air then H2 , the charge variation of Pt- α -MoO3 monolayer reaches to a large value of 1.487 e for per O 2 /H 2. • The shift of the Fermi level conforms the larger charge variation. [Display omitted] [ABSTRACT FROM AUTHOR]

Symmetric batteries received an increasing research interest in the past few years because of their simplified fabrication process and reduced manufacturing cost. In this study, we propose the first dual‐ion organic symmetric cell based on a molecular anion of 4,4′‐(phenazine‐5,10‐diyl)dibenzoate. The alkali salt of 4,4′‐(phenazine‐5,10‐diyl)dibenzoate allows a facile transport of cations and large anions, and remains stable in both oxidized and reduced states. The large potential difference between phenazine and benzoate results in a high cell voltage of 2.5 V and an energy density of 127 Wh kg−1 at a current rate of 1 C. The introduction of bipolar organic materials may further consolidate the development of symmetric batteries that are fabricated from abundant elements and environmentally friendly materials. [ABSTRACT FROM AUTHOR]

Symmetric batteries received an increasing research interest in the past few years because of their simplified fabrication process and reduced manufacturing cost. In this study, we propose the first dual‐ion organic symmetric cell based on a molecular anion of 4,4′‐(phenazine‐5,10‐diyl)dibenzoate. The alkali salt of 4,4′‐(phenazine‐5,10‐diyl)dibenzoate allows a facile transport of cations and large anions, and remains stable in both oxidized and reduced states. The large potential difference between phenazine and benzoate results in a high cell voltage of 2.5 V and an energy density of 127 Wh kg−1 at a current rate of 1 C. The introduction of bipolar organic materials may further consolidate the development of symmetric batteries that are fabricated from abundant elements and environmentally friendly materials. [ABSTRACT FROM AUTHOR]

Abstract Organic redox flow batteries receive increasing interest for large-scale electrical energy storage owing to the structural diversity and elemental abundance of organic compounds. However, their implementation is challenged by the cyclability, which is an order of magnitude lower than traditional redox flow batteries using inorganic redox couples. The unsatisfactory cyclability mainly arises from electrolyte contamination and irreversible losses of active material in the electrolyte. To address such issues, a highly water-soluble artificial bipolar molecule containing cathode-active ferrocene moiety and anode-active bipyridinium moiety is realized and used as the sole active material in a symmetric organic redox flow cell. Owing to the good reversibility, minimum electrolyte contamination, and stability of the synthesized molecule, the demonstrated cell boosts the cyclability to 4000 cycles with capacity retention of ca. 75% at 100% depth of discharge, which fills in the gap of cyclability between organic redox flow batteries and conventional redox flow batteries. Graphical abstract Image 1 Highlights • A highly water-soluble bipolar molecule is designed and synthesized for SORFB. • The demonstrated SORFB overcomes the technical constraints of traditional RFBs. • The SORFB shows stable cycling performance and round-trip efficiencies. [ABSTRACT FROM AUTHOR]

This study focused on the antibacterial effects of the endophytic fungi producing naringenin from Dalbergia odorifera T. Chen against Staphylococcus aureus. The antibacterial activity was measured by the inhibition diameters, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The time-killing curve was also used to evaluate its antibacterial efficacy. The results of antibacterial activity determinations showed that endophytic fungi secondary metabolites can inhibit the growth of five pathogenic bacteria (S. aureus, Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa, and Bacillus subtilis) and the most sensitive strain was S. aureus that had the MIC and MBC values of 0.13 and 0.50 mg/mL, respectively. The membrane permeability study was measured by a DNA leakage assay and electrical conductivity assay. Furthermore, the whole-cell protein lysates and DNA fragmentation assay was evaluated. The morphology of S. aureus treated with the endophytic fungi products was observed by scanning electron microscopy (SEM). The probable antibacterial mechanism of endophytic fungi secondary metabolites was the increased membrane permeability that leads to leaks of nucleic acids and proteins. SEM results further confirmed that the extracts can interfere with the integrity of S. aureus cell membrane and further inhibit the growth of bacteria, resulting in the death of bacteria. This study provides a new perspective for the antibacterial functions of endophytic fungi secondary metabolites for biomedical applications. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI), a common clinical type of critical illness, is an acute hypoxic respiratory insufficiency caused by the damage of alveolar epithelial cells and capillary endothelial cells. In a previous study, we reported a novel lncRNA, lncRNA PFI, which could protect against pulmonary fibrosis in pulmonary fibroblasts. The present study demonstrated that lncRNA PFI was downregulated in alveolar epithelial cell of mice injury lung tissues, and further investigated the role of lncRNA PFI in regulating inflammation-induced alveolar epithelial cell apoptosis. Overexpression of lncRNA PFI could partially abrogated bleomycin induced type II AECs injured. Subsequently, bioinformatic prediction revealed that lncRNA PFI might directly bind to miR-328-3p, and further AGO-2 RNA binding protein immunoprecipitation (RIP) assay confirmed their binding relationship. Furthermore, miR-328-3p promoted apoptosis in MLE-12 cells by limiting the activation of the Creb1, a protein correlated with cell apoptosis, whereas AMO-328-3p ablated the pro-apoptosis effect of silencing lncRNA PFI in MLE-12 cells. While miR-328-3p could also ablate the function of lncRNA PFI in bleomycin treated human lung epithelial cells. Enhanced expression of lncRNA PFI reversed the LPS-induced lung injury in mice. Overall, these data reveal that lncRNA PFI mitigated acute lung injury through miR-328-3p/Creb1 pathway in alveolar epithelial cells. [ABSTRACT FROM AUTHOR]

With the implementation of stringent emission regulations and the growth of electric vehicles, more attention should be shifted to road traffic-derived non-exhaust emissions. Tyre wear particle (TWP) emissions have outweighed those from the exhaust and are potential for microplastic pollution. However, there are no regulations that specifically limit TWP emissions and no feasible technologies to curb the emissions. Due to the varied measurements and discrepant data, the related results are incomparable and uncertain. This paper gives a comprehensive overview of TWP from four aspects: formation mechanisms, experimental methods, emission characteristics, and influencing factors. Real-road TWP are generally incorporated with existing road particles, so the sampling methods need to be carefully designed to eliminate the influence of undesired particles. In this case, the TWP scattering paths, the effects of sampling flow rate and sampling inlet location, the design principles of sampling geometry based on sampling flow rate and vehicle speed are discussed. The micro-vibration and the stick-slip oscillation between the tyre and road, coupled with the evaporation of tread volatile compounds, lead to the TWP formation. Thus, TWP covers a broader size distribution, diverse shapes, and multiple chemical components. Further studies should be focused on the physicochemical properties of TWP by standardizing experimental procedures and narrow controlling the main influencing factors of vehicle driving behaviours, road types, tyre specifications, and the ambient environment. • TWP sampling, analysis, and parameters affecting the efficiency are summarized. • TWP formation, scattering path, emission, and physicochemical property are compared. • Effects of major influencing factors of driving and environment are discussed. [ABSTRACT FROM AUTHOR]

Particles emitted during braking account for a significant proportion of transport-related particles. The brake particles are still beyond supervision because no mandatory regulations were introduced to control the brake particle emissions. Many studies have been conducted about the brake particles, but the materials & methods used by these studies vary a lot, thus reducing the result comparability among these studies. This paper reviewed brake particle emissions from four aspects: experimental methods, emission characteristics, influencing factors, and future works. Six experimental methods corresponding to different application scenarios are summarized, and these methods require different modifications, skills, and expenses. Whatever the experimental methods, the sampling method needs careful design to reduce the particle transport loss and to ensure particle sampling efficiency. The reported brake particle emissions could exceed the sixth stage exhaust emission regulation (both EU and China), depending on the test procedures, friction materials, and data processing. The brake particle covers a broad size distribution (from a few nanometers to tens of microns), and more studies are needed about its physicochemical characteristics. The friction materials, system running-in, and friction temperature will significantly affect the brake particle emission characteristics, and these factors should be considered when designing the study procedure. The patterns about gaseous emission and non-brake particle emission need more attention, as these patterns might be helpful to understand the brake particle emission characteristics. Some filter&collection-based brake particle after-treatments have also been invented. Future studies should focus on the homogeneous test procedure, mechanism analysis, after-treatment, and non-airborne wear et al. • Different brake particle research methods were assessed. • Brake particle emission characteristics are summarized and compared. • Major factors affecting the brake particle emission are analyzed. • Future concerns for brake particle emission are proposed. [ABSTRACT FROM AUTHOR]