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Dynamically responsive materials, capable of reversible changes in color appearance and/or photoemission upon external stimuli, have attracted substantial attention across various fields. This study presents an effective approach wherein switchable modulation of photochromism and ultralong phosphorescence can be achieved simultaneously in a zero-dimensional organic-inorganic halide hybrid glass doped with 4,4´-bipyridine. The facile fabrication of large-scale glasses is accomplished through a combined grinding-melting-quenching process. The persistent luminescence can be regulated through the photochromic switch induced by photo-generated radicals. Furthermore, the incorporation of the aggregation-induced chirality effect generates intriguing circularly polarized luminescence, with an optical dissymmetry factor (glum) reaching the order of 10–2. Exploiting the dynamic ultralong phosphorescence, this work further achieves promising applications, such as three-dimensional optical storage, rewritable photo-patterning, and multi-mode anti-counterfeiting with ease. Therefore, this study introduces a smart hybrid glass platform as a new photo-responsive switchable system, offering versatility for a wide array of photonic applications. Dynamically responsive afterglow materials are typically fabricated as single crystals, polymers or powders. Here, the authors use zero-dimensional metal halides and organic dopants to develop photochromic glasses for diverse optical applications. [ABSTRACT FROM AUTHOR]

The oxygen evolution kinetics of industrial copper electrodeposition is slow, resulting in low electrocatalytic activity and high energy consumption. In this work, a quaternary composite of carbon coated active particles containing Mn, Co and Ce were prepared (Mn-Co3O4/CeO2@C), and Ti/Sb-SnO2/PbO2 electrode doped with these active particles was prepared by co-electrodeposition. The microstructure and chemical composition of the electrode was characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffractometry (XRD). Linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and Tafel polarization curve (Tafel) were used to study the electrochemical properties of anode materials. The results showed that the doping of Mn-Co3O4/CeO2@C active particles promoted the crystal transition of PbO2, decreased the average grain size, and the doping of Ce increases the average valence state of Co. The modified titanium electrode showed excellent catalytic activity of the oxygen evolution reaction (OER) characteristics. The overpotential of the doped Ti/Sb-SnO2/PbO2 anode was only 453 mV when the current density was 20 mA cm−2 in 0.5 M H2SO4 solution, which is 508 mV lower than that of the undoped Ti/Sb-SnO2/PbO2 anode. In simulated copper electro-deposition experiments, the cell voltage was reduced by about 400 mV, compared to the undoped Ti/Sb-SnO2/PbO2 electrode. [ABSTRACT FROM AUTHOR]

The fabrication of chiral molecules into macroscopic systems has many valuable applications, especially in the fields of optical displays, data encryption, information storage, and so on. Here, we design and prepare a serious of supramolecular glasses (SGs) based on Zn-L-Histidine complexes, via an evaporation-induced self-assembly (EISA) strategy. Metal-ligand interactions between the zinc(II) ion and chiral L-Histidine endow the SGs with interesting circularly polarized afterglow (CPA). Multicolored CPA emissions from blue to red with dissymmetry factor as high as 9.5 × 10−3 and excited-state lifetime up to 356.7 ms are achieved under ambient conditions. Therefore, this work not only communicates the bulk SGs with wide-tunable afterglow and large circular polarization, but also provides an EISA method for the macroscopic self-assembly of chiral metal–organic hybrids toward photonic applications. Material designs with multicolor circularly polarized emissions are desirable for photonic applications. Here, the authors report supramolecular glasses based on self-assembled chiral metal–organic complexes with color-tunable circularly polarized afterglow. [ABSTRACT FROM AUTHOR]

Large-scale electrolysis of water to produce high-purity hydrogen is one of the effective ways to solve the energy crisis and environmental pollution problems. However, efficient, cheap and stable catalysts are one of the bottlenecks for industrial application in water splitting. Herein, a facile one-step hydrothermal process was applied to fabricate Mn-doped nickel ferrite nanosheets (Mn-NiFe2O4) which shown a low overpotential of 200 mV at 50 mA·cm−2 and a small Tafel slope of 47 mV·dec−1, together with a prominent turnover frequency (TOF) value (0.14 s−1) and robust stability. The in-situ UV—vis spectroscopy unveiled the surface reconstruction to generate NiOOH as active sites during oxygen evolution reaction (OER). The excellent electrocatalytic activity of Mn-NiFe2O4 is attributed to the vertically grown nanosheets for exposure more active sites, rich oxygen vacancies, and the hybridization between Ni 3d and O 2p orbitals caused by Mn doping. This work should provide a facile strategy by Mn-doping to simultaneously engineer oxygen vacancies and electronic structure for synergistically triggering oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Since the summer of 2017, bacterial fruit black rot disease was observed on prickly ash (Zanthoxylum armatum DC., Yongqing No. 1) in three counties (Yongshan, Qiaojia and Ludian) of Zhaotong City, Yunnan Province, that kills the fruit, results in significant yield reduction, severely affects quality of fruit and even worst has no harvest. A combination of cultural, biochemical and physiological characterizations, Biolog analyses, MALDI-TOF MS analyses, multi-locus phylogenetic analyses and pathogenicity assays revealed that Pseudomonas oryzihabitans was the pathogen associated with the fruit black rot. The pathogenicity was verified with Koch's postulates. To our knowledge, this study provides the first report of fruit black rot caused by P. oryzihabitans on prickly ash. [ABSTRACT FROM AUTHOR]

A novel copper-based metal-organic framework (Cu-MOF) with a large specific surface area and high porosity was synthesized. The Cu-MOF was a good peroxidase-mimicking enzyme and showed a high affinity with hydrogen peroxide in a wide pH range. The catalytic mechanism of Cu-MOF has been studied further based on comparing the characteristic of the Cu-MOF with some isomorphic MOFs. The catalytic activity center of Cu-MOF was determined to be the cupric ion rather than the ligand, which effectively promoted the generation of free radicals and electron transfer in the reaction progress. The high affinity of Cu-MOF to hydrogen peroxide proved it as an ideal catalyst for the chemiluminescence (CL) reaction involving hydrogen peroxide. Therefore, the CL method with high sensitivity could be established for detecting various substrates. A double-enzyme CL glucose biosensing platform was constructed for the determination of serum glucose employing the peroxidase-mimicking properties of Cu-MOF as well as glucose oxidase (GOx). [ABSTRACT FROM AUTHOR]

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The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brittle fault system. There are three types of primary ore including auriferous calcite vein type, disseminated type, and breccia type, and the first two are important in the Phapon gold deposit. Based on fluid inclusion petrography and microthermometry, three types of primary fluid inclusions including type 1 liquid-rich aqueous, type 2 vapor-rich aqueous and type 3 daughter mineral-bearing aqueous were identified in hydrothermal calcite grains. The ore-forming fluids are normally homogeneous, as indicated by the widespread type 1 inclusions with identical composition. The coexistence of type 1 and type 2 inclusions, showing similar final homogenization temperature but different compositions, indicate that fluid immiscibility did locally take place in both two types of ores. The results of microthermometry and H-O isotopes geochemistry indicate that there are little differences on ore-fluid geochemistry between the auriferous calcite vein-type and disseminated type ores. The oreforming fluids are characterized by medium-low temperatures (157—268 °C) and low salinity (1.6 wt.%-9.9 wt.% NaCl eq.). It is likely to have a metamorphic-dominant mixed source, which could be associated with dehydration and decarbonisation of Lower Permian limestone and Middle-Upper Triassic sandstones during the dynamic metamorphism. The fluid-wallrock interaction played a major role, and the locally occurred fluid-immiscible processes played a subordinate role in gold precipitation. Combined with the regional and ore deposit geology, and ore-fluid geochemistry, we suggest that the Phapon gold deposit is best considered to be a member of the epizonal orogenic deposit class. [ABSTRACT FROM AUTHOR]

An integrated study of zircon U-Pb geochronology and petrochemistry, together with zircon Lu-Hf isotopes, has been carried out on the basaltic-andesitic tuff and volcanic breccia from the Nam Hang Formation and andesitic tuff from the Muang-Nan Formation in the Xaignabouli area, which had been mapped as the Permian-Early Triassic on the 1 : 1 000 000 geological map or Late Carboniferous on the 1 : 200 000 geological maps. Zircon U-Pb dating of three samples yielded weighted mean ages of 235±2.6, 232±1.4 and 278±2.8 Ma, respectively, suggesting a Late Triassic origin for the Nam Hang Formation and an Early Permian origin for the Muang-Nan Formation. Geochemically, they are characterized by depletions in HFSEs (e.g., Nb, Ta, Ti) and high LILE/HFSE ratios, and they have positive zircon εHf(t) values of 8.7-15.9, which exhibits the continental arc volcanic affinity and partial melting of subducting oceanic slab in the magma source. Combined with spatial occurrence of the volcanic rock and existing geochronological and geochemical data, we suggest that the Xaignabouli-Luang Prabang volcanic belt can be linked to the Loei-Phetchabun belt. The Permian-Triassic volcanic rocks in this belt might be a product of the Nan back-arc basin eastward subduction. [ABSTRACT FROM AUTHOR]

A functional Ag-Fe3O4-grapheme oxide magnetic nanocomposite was synthesized and used to prepare a nitrite sensor. Morphology and composition of the nanocomposites were characterized by a transmission electron microscope, UV-VIS spectroscopy, X-ray diffraction, and Fourier transform infrared spectra. Electrochemical investigation indicated that the nanocomposites possess excellent electrochemical oxidation ability towards nitrites. The sensor exhibited two linear ranges: one from 0.5 μM to 0.72 mM with a correlation coefficient of 0.996 and sensitivity of 1996 μA mM−1 cm−2; the other from 0.72 mM to 8.15 mM with a correlation coefficient of 0.998 and sensitivity of 426 μA mM−1 cm−2. The limit of detection of this sensing system was 0.17 μM at the signalto- noise ratio of 3. Additionally, the sensor exhibited long-term stability, good reproducibility, and anti-interference. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG) as a promoting material for CO separation performance of a composite membrane is introduced into the polytrifluoropropylmethylsiloxane (PTFPMS) network to form a blend selective layer coated on a porous polyetherimide (PEI) support membrane. The maximum blend ratio of PEG to PTFMS in mass is determined for PEG-400, PEG-600, and PEG-1000 at 0.5, 0.2 and 0.2 from the blend solution status observed by an optical microscope. The miscibility of PEG and PTFPMS is verified from one peak of the blend film in DSC characterization. Furthermore, the interaction between PEG and PTFPMS is van der Waals force from the decreasing strength of ether group in ATR-FTIR analysis. The stability of the PEG/PTFPMS blend composite membrane is investigated with pure N, O, and CO permeation experiments under the transmembrane pressure difference up to 1.0 MPa. The N permeation rate of the PEG400/PTFPMS blend composite membrane with a blend ratio of 0.2 is 2.11 GPU, while the O/N and CO/N selectivities are improved to 2.67 and 26.67, respectively, which are higher than those of pure PTFPMS composite membrane that is 2.2 and 13.79, respectively. [ABSTRACT FROM AUTHOR]

An ultrasensitive sandwich electrochemiluminescence (ECL) biosensor was designed for determination of concanavalin A (ConA) through the specific carbohydrate-ConA interactions. Three-dimensional porous metal-organic framework (Zn-MOF) was synthesized, which loaded a large amount of luminescent reagents as luminol by encapsulating into its pores to form Zn-MOF@luminol complex. Interestingly, Zn-MOF also acted as the coreactant accelerator in the luminol-H2O2 ECL system. This Zn-MOF@luminol complex was used as the signal probe to achieve a super strong and stable ECL signal. In addition, three-dimensional hierarchical molybdenum disulfide nanoflower and multiwalled carbon nanotubes complex (MoS2NF@MWCNTs) with peroxidase-mimicking enzyme property were used as a substrate to modify the glassy carbon electrode to further enhance the ECL signal of luminol by promoting decomposition of H2O2 into reactive oxygen species (ROSs). In addition to the horseradish peroxidase (HRP) catalysis effect on the luminol ECL signal, a triple amplified ConA sandwich ECL sensor with high sensitivity sensor was constructed. The linear range for ConA detection was from 0.5 pg/mL to 100 ng/mL with a detection limit of 0.3 pg/mL (S/N = 3). The recovery test for ConA in human serum samples was performed with satisfactory results. [ABSTRACT FROM AUTHOR]

The fifth author's name was wrong and it should be replaced as ZHANG Jian-long(张建龙)2. [ABSTRACT FROM AUTHOR]

A new sandwich structure nanocomposite of Ag nanoparticles supported on TiO-functionalized graphene nanosheet was synthesized, involving a simple chemical reduction of GO using TiCl as reducing agent and the in situ formation of TiO as linker between r-GO and Ag. Based on the Ag/TiO/r-GO hybrid material, a novel electrochemical sensor for the determination of nitrite was constructed. The morphology and composition of the nanocomposite were characterized by transmission electron microscope and UV-vis absorption spectra. Electrochemical investigation indicated that Ag/TiO/r-GO modified electrode exhibited excellent electrocatalytic performance for the oxidation of nitrite. The sensor showed a wide linear range from 1.0 µM to 1.1 mM, with the detection limit of 0.4 µM, the sensitivity of 112.0 μA mM cm. Additionally, the proposed method was successfully applied to the detection of nitrite in water samples with obtained satisfactory results. [ABSTRACT FROM AUTHOR]

Nanofilms of titanium dioxide (TiO) nanoparticles that mediate the assembly of polystyrene (PS) nanoparticles for immobilizing hemoglobin (Hb) on carbon ionic liquid electrode have been developed. Fourier transform infrared spectroscopy shows that Hb retains its native structure in TiO-PS nanofilms. Scanning electron microscopy reveals that the nanofilms possess uniform morphology and Hb is immobilized on the surface of the nanofilms. Electrochemical investigation of the biosensor indicates that the direct electrochemistry of hemoglobin is realized on the nanofilms, and there is a formal potential of −0.320 V in deaerated buffer solutions; the biosensor shows good electrocatalytic activity toward the reduction of hydrogen peroxide with a linear range from 0.5 to 640 μM, a detection limit of 0.2 μM ( S/ N = 3) and a sensitivity of 103 μA mM. Thus, the nanofilms will have potential application in the design of novel electrochemical biosensors. [ABSTRACT FROM AUTHOR]