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This study proposes a sensorless control method for the permanent magnet synchronous machine (PMSM) drive that is robust against load torque variations. The proposed method is based on the disturbance observer-based control (DOBC) method, and involves the use of a back electromotive force observer and a torque observer to estimate rotor position and compensate for load torque disturbance, respectively. This mechanism is simple to implement and requires no state vector derivation. The gains of the two observers are carefully selected to improve estimation accuracy and dynamic performance. The performance of the proposed load DOBC for sensorless PMSM drives was tested through a simulation, where the sensorless estimation error was considered to determine the adjustment laws for the proposed observer gains. Furthermore, results of evaluative experiments verified the effectiveness of the proposed method for high-performance sensorless control and torque disturbance rejection for the PMSM drive. [ABSTRACT FROM AUTHOR]

Abstract: A novel sensor based on thiol-porphyrin mixed monolayer-tethered polyaniline (PANI) with intercalating fullerenols was applied to sensitively detect m-dinitrobenzene (m-DNB) by differential pulse voltammetry (DPV). The thiolated polyaniline was examined by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrode modification of thiol-porphyrin mixed monolayer-tethered polyaniline with intercalating fullerenols exhibited a higher analytical sensitivity versus that of thiol-porphyrin mixed monolayer-tethered polyaniline, because the fullerenols in mixed monolayer could improve the preconcentration efficiencies of m-DNB. Under optimum conditions, the linear calibration curves ranged from 0.029 to 10,000nmolL−1 for m-DNB, with a limit of detection (S/N=3) of 9.72pmolL−1. [Copyright &y& Elsevier]

Highlights: [•] We described cathodic ECL on metal nanoparticles modified electrode. [•] Ag and Cu were firstly used as co-reactants in Ru-system. [•] Possible mechanism was discussed according to the present results. [•] Metal nanoparticles could become a promising material for ECL investigations. [Copyright &y& Elsevier]

Rapid and accurate eddy-current calculation is necessary to analyze eddy-current couplings (ECCs). This paper presents a general 3D analytical method for calculating the magnetic field distributions, eddy currents, and torques of ECCs with different Halbach magnet arrays. By using Fourier decomposition, the magnetization components of Halbach magnet arrays are determined. Then, with a group of H-formulations in the conductor region and Laplacian equations with magnetic scalar potential in the others, analytical magnetic field distributions are predicted and verified by 3D finite element models. Based on Ohm's law for moving conductors, eddy-current distributions and torques are obtained at different speeds. Finally, the Halbach magnet arrays with different segments are optimized to enhance the fundamental amplitude and reduce the harmonic contents of air-gap flux densities. The proposed method shows its correctness and validation in analyzing and optimizing ECCs with Halbach magnet arrays. [ABSTRACT FROM AUTHOR]

Abstract: Photoinduced electron transfer with the electron donor–acceptor linked system of zinc-5,10,15,20-tetraphenylporphyrin (ZnTPP) as donor and benzoquinone (BQ) as acceptor was designed to mimic the electron transfer process in photosynthetic reaction center. Within the framework of the bimolecular electron transfer mechanisms of scanning electrochemical microscopy (SECM), the fundamental features of photoinduced electron transfer were demonstrated by recording the feedback approach curves under different light wavelength, intensity, and concentration of BQ. Meanwhile, relevant theoretical study was employed to support our proposal. It demonstrated that SECM as a new platform could also provide crucial information for simple simulation of the electron transfer process in photosynthetic reaction center. [Copyright &y& Elsevier]

In order to investigate the electrochemical properties of porphyrin complexes species in biological systems, metalloporphyrin with different substitutes was applied to observe the process of heterogeneous electron transfer (ET) at the interface between two immiscible electrolyte solutions (ITIES) by scanning electrochemical microscopy (SECM). Experimental results demonstrated that the process of electron transfer was affected dramatically by the presence of different substitutes. Our results also show that the rate constant follows BulterVolmer kinetics where the rate increases with increasing force at the low driving force, and Marcus inverted region kinetics at the high driving force where the rate decreases. [ABSTRACT FROM AUTHOR]

Abstract: Cytosolic phospholipase A2α, one of the three subtypes of Cytosolic phospholipase A2 (α, β and γ), is deemed to play an important role in the arachidonate pathway. Due to the rate-limiting provider for proinflammatory mediators, it is a particularly attractive target for drug development. Studies have revealed that indol derivate compounds can inhibit the activities of Cytosolic phospholipase A2α. However, few papers on the relationship between the molecular structure and the activity of inhibitor were reported. In this study, the Quantitative Structure Activity Relationship (QSAR) of indole derivates has been performed based on the dataset of 49 compounds. By using stepwise multiple linear regression, 5 descriptors were selected from 1777 molecular descriptors, including GGI5 (Topological charge index G5), TIE(dssC) (sum of E-State of atom type dssC: ¦2S(dssC)), RDF115a (the atomic Sanderson ALOGP), RDF100c (the atomic charge), and RDF065p (the atomic polarizability). Subsequently, Partial Least Squares (PLS), Artificial Neural Networks (ANN) and Support Vector Machine (SVM) were adopted to build the QSAR model, respectively. The independent test indicated that the SVM can give the best statistical results. And indole derivative inhibitors activity might be related to global charge transfers, carbon atoms type linked benzyl sulfonamide and molecule geometrical the distance distribution. [Copyright &y& Elsevier]

Abstract: We demonstrate that core–shell multi-component nanocomposites can be grown in situ at room temperature by a novel one-step approach without adding any reductant and stabilizer. We have presented a one-step method for the synthesis of multi-component nanocomposites in water solution, the multi-component nanocomposites could be produced directly and quickly in an in situ wet-chemical reaction. Here, Au–polypyrrole (PPy)/Prussian blue (PB) nanocomposites have been synthesized successfully under the same circumstance. With the addition of pyrrole monomers into mixture solutions, the autopolymerization of pyrrole into PPy and AuCl4 − was reduced to elemental Au instantaneously as well as simultaneously. At the same time, PB produced along with elemental Au serving as a catalyst. Furthermore, we investigated the performance of Au–PPy/PB nanocomposites as amperometric sensor toward the reduction of H2O2, which displayed high sensitivity, fast response and good stability. The peak current of H2O2 increased linearly with the concentration of H2O2 in the range from 2.5×10−9 to 1.2×10−6 M, and the low detection limit of 8.3×10−10 M (S/N=3) was obtained. Therefore, this work provides a new pathway to design and fabricate novel multi-component nanocomposites, which have unique characteristics and hold great applications in the fields of sensors, electrocatalysis and others. [Copyright &y& Elsevier]

Abstract: The hydroxide of meso-tetraphenylporphyrin derivatives functionalized carbon nanotubes (CNTs) was fabricated in our research to explore the interaction between porphyrin and explosive. It was turned out that in the formation of grid porphyrin film, carbon nanotubes as a cruciul base materials promoted the electron transfer rate. Most of important, the results also showed that the electrochemical response was enhanced through increasing the number of –OH substitution in porphyrin. Such information provides the platform for a practical strategy for rational design of the sensor of explosives. [Copyright &y& Elsevier]

Abstract: Porphyrin is able to specifically combine with phosphorus, thus a novel bifunctional sensing platform for determination of porphyrin by visual colorimetry and electrochemistry was demonstrated. A pretreated gold sheet (or electrode) with 2-mercatpoethanol (2-ME) was chemically modified by POCl3 to obtain the surface phosphate active sites. The different stages of modified electrode were characterized by electrochemical impedance spectroscopy (EIS). The 1:1 cationic sitting-atop (SAT) complex P(V)–porphyrin was formed due to the high affinity of the modified gold sheet (or electrode) towards the porphyrin, resulting in electron transfer resistance increase of the electrode surface. Meanwhile, a dramatic color changing from burgundy to dark green of porphyrin solution was observed with the naked-eye within 3s. What''s more, this was reflected by the notable change of the Soret band of porphyrin when using UV–vis. Two sensing systems provide different sensitivity for porphyrin analysis. With visual colorimetry, porphyrin can be detected at a level of 1.0×10−6 M, whereas the detection limit of porphyrin is 3.0×10−8 M using the EIS method. The practical application of the sensor to determination of pheophytin which was obtained from fresh spinach leaves has been accomplished. The results demonstrate the facility and effectivity of our introduced bifunctional biosensor for quantitative analysis of porphyrin. [Copyright &y& Elsevier]

Abstract: A novel nanocomposites film of conducting polymers including single-walled carbon nanotubes (SWCNTs), polypyrrole (PPy) and gold nanoparticles (AuNPs) modified electrode has been applied in voltammetric sensors to detect epinephrine (EP) sensitively when ascorbic acids (AA) and uric acids (UA) exist. The nanocomposites film of conducting polymers which show an excellent electrocatalystic activity for the oxidation of EP and UA was characterized by scanning electron microscopy (SEM) and electrochemical methods. The catalytic peak currents obtained from differential pulse voltammetry (DPV) increased linearly with increasing EP concentrations in the range of 4.0×10−9–1.0×10−7 M with a detection limit of 2.0×10−9 M (S/N=3), respectively. The results showed that the nanocomposites of conducting polymers can selectively determine EP in the coexistence of a large amount of UA and AA. In addition, the sensor exhibited excellent sensitivity, selectivity and stability. The PPy/AuNPs/SWCNTs nanocomposites film can also be satisfactorily used for detecting EP in epinephrine hydrochloride injection when contain AA and UA, which also shows good recovery for determination of EP in some biological fluids. [Copyright &y& Elsevier]

Abstract: Substituent effects of iron porphyrin complexes on the structures and kinetic processes have been examined for the first time. Basing on the premise that iron porphyrin is functional analogous to heme, a series of iron porphyrin derivatives bearing different substituents at the meso positions of the corrole ring are investigated as to their electrochemistry, the relationships among the electron transfer (ET) processes, their structures, and orbital energies. The good coherence between the experiment and theory indicates that the ET rate can be accelerated when electron-donating substituents are introduced to the iron porphyrin ring. Finally, the implications of the results are discussed in the influence of stability of iron porphyrin complexes on the ability to carry molecular oxygen, which may suggest it possible to dominate the biological activity of heme by selecting the appropriate substituents to iron porphyrin ring. [Copyright &y& Elsevier]

Abstract: Multilayers film of nanostructured gold nanoparticles (AuNPs) has been fabricated based on the layer-by-layer (LBL) technique using a self-assembled monolayer of 5,15-di-[p-(6-mercaptohexyl)-phenyl]-10,20-diphenylporphyrin (trans-PPS2). AuNPs act as physical cross-link points in the multilayers. Electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) are applied to study the formation of the organic–inorganic multilayers film and have determined the electrochemical parameters, i.e., the heterogeneous electron transfer rate constant (K et). The observed phenomena indicate that the electron transfer (ET) process is affected by material properties and the molecular structure of self-assembled monolayers (SAMs). Using the high sensitivity of ET of ferricyanide to the modification of the gold surface with multilayers film, we select this reaction as a probe to study the different modification stages at this modified electrode. ET is retarded on the trans-PPS2 alternative deposition of layers on the electrode surface and is accelerated on the AuNPs’ layers. SECM images are used to collect surface information in the course of the successive modification process. SECM images obtained from bare and different modification stages show very high resolution with different topographies. [Copyright &y& Elsevier]

As a typical oscillating chemical system, the frequency characteristic of photochemical oscillatory system is analyzed by a reliable oscillation frequency spectrum (OFS) approach. The results show that every periodic signal have a special OFS. The relative standard deviation (RSD) values of frequencies of four relative oscillating signals which belong to photochemical oscillatory system are extracted. They have multi-frequency characteristic. OFS successfully realizes the extraction and calculation of photochemical oscillatory system. OFS can be used to analyze the frequency of complex periodic signal accurately and be suitable for many areas. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on investigating the structure parameters of antibiotics which have decisive influence on the interactive mode between antibiotics and DNAs. The analytical results of Best Prediction Set Support Vector Machine Method (BPSSVM) show that the number of N atoms, the number of double bonds, the number of lone-pair electrons, the molar refractivity and the molecular radius are the main structure parameters which functionally decide their reactive modes. It is clear that the BPSSVM is potent in predicting the interactive modes between antibiotics and DNAs. [Copyright &y& Elsevier]

Abstract: Self-assembled monolayers (SAMs) of thiol-porphyrins with different alkyl chain length (abbreviated as H2TPPO(CH2) n SH, n =3, 6, 9 and 12) on gold electrode have been studied by electrochemical impedance spectroscopy in electrolytes containing a one-electron redox couple. From the size and separation of pinholes on SAMs, both estimated the values of charge-transfer resistance and pore size model, we get the surface coverage (θ). The results demonstrate that the surface coverage of saturated porphyrin modified gold electrode is close to unity (>99%). But on the SAMs, a large number of pinholes still exist and acting as the microelectrodes, with average pinhole radius of 4–6 μm and the separations are ten times greater than the pinhole size, of 40–70 μm. Moreover, long chain length thiol-porphyrin SAM shows high surface coverage, larger pinhole size and excellent blocking of electron-transfer reactions between the redox mediator and the gold substrate. We demonstrated the large pinhole size is due to the aggregation of mass individual “micro-holes”. [Copyright &y& Elsevier]

Abstract: Scanning electrochemical microscopy (SECM) has been proven to be a valuable technique for the quantitative investigation and surface analysis of a wide range of processes that occur at interfaces. In particular, there is a great deal of interest in studying the kinetics of charge transfer characteristics at the solid/liquid and liquid/liquid interface. This overview outlines recent advances and applications of SECM to the investigation of charge transfer reactions at the solid/liquid interface and liquid/liquid interface. [Copyright &y& Elsevier]

Abstract: In this paper, 24 parameters (descriptors) that can influence the interaction of selected antibiotic compound (antibiotics) and DNA have been investigated. Principal components analysis (PCA) and hierarchical cluster analysis (HCA) were employed in order to reduce dimensionality and investigate which subset of variables could be more effective for classifying the antibiotics according to their binding mode with DNA. Results of the PCA and HCA study showed that there are 12 descriptors closely related to the interaction. Based on these descriptors, multiple linear regression (MLR) and artificial neutral network (ANN) allowed us to propose three models which can predict binding constant and binding mode. For the prediction of binding constant, the minimal relative error is only 0.17% (MLR) and 0.72% (ANN); for the prediction of binding mode (ANN), five test molecules are all consistent with experimental results. [Copyright &y& Elsevier]

A series of thiol‐derivatized porphyrins with one to four [p‐(3‐mercaptopropyloxy)‐phenyl] groups appended to the meso‐position of the porphyrins, have been synthesized and shown to form molecular monolayers via irreversible chemical adsorption on the surface of gold via S‐Au linkage to form a highly ordered surface with fewer defects and exhibit a high degree of orientation, molecular ordering, packing density and thus as new chemically modified electrodes to study their electrochemical properties. Electrochemical surface coverage determinations, although not conclusive, suggested near monolayer coverage with preferential binding of the porphyrin ring perpendicular or coplanar to the gold surface. With post‐assembly insertion of Cobalt(II) into tetra‐[p‐(mercaptoprophyloxy)‐phenyl] porphyrin (H2TMPP) monolayers on gold electrode, molecular films of CoTMPP reduce dioxygen at potentials consistent with two‐electron reduction to hydrogen peroxide and a lower limit to the rate constant (k) for the reaction of dioxygen is 4.03×104 M-l s-l. [ABSTRACT FROM AUTHOR]

Abstract: Scanning electrochemical microscopy (SECM) technology has been used to investigate the kinetics of heterogeneous electron transfer (ET) as a function of driving force at the interface between two immiscible electrolyte solutions (ITIES). The ET between metalloporphyrin species containing different substitutes in nitrobenzene and other redox species in the aqueous phase was studied and the rate constants were also extracted from the dependence of the steady-state current at a micrometer-sized tip electrode on the distance between the tip and the phase boundary when compared with the theoretical working curves. Corresponding to the various metalloporphyrin substitutes, SECM was demonstrated to be a useful means to study the effect of molecular structure on the kinetics of heterogeneous ET. [Copyright &y& Elsevier]

Abstract: A novel thiol-derivative porphyrin (5-[p-(mercaptopropyloxy)-phenyl]-10,15,20-triphenylporphine shortly as H2MPTPP) and its cobalt(II) complex (MPTPPCo(II) ) have been successfully immobilized on gold surface by self-assembly technique. The surface coverages (Γ) of MPTPPCo(II) was calculated to be 4.86×10−11 mol/cm2 by investigating the reductive desorption of S–Au which demonstrated that the monolayer was not packed well and had many interval pinholes. The gold electrodes modified with MPTPPCo(II) and MPTPPCo(II)+thiolglycolic acid show good activity to the two-electron catalytic reduction of O2 to H2O2. Nanoscopic structures gained by atomic force microscopy (AFM) not only provided further evidence for the successful formation and immobilization of such monolayers, but also elucidated the potential reasons for the electrocatalytic activity of such monolayers to dissolved oxygen, which was proved to be very interesting and significant that the mixed monolayer could enhance the electroreduction and proceed more readily for the electroreduction of O2. [Copyright &y& Elsevier]

The electrochemical characteristics of kanamycin onto self-assembled monolayer (SAM) modified gold electrode (SAM/Au) is investigated by cyclic voltammetry. In the potential range 0–0.6 V, Cu(II) yields a pair of stable redox waves at the bare gold electrode. Epa is located at 0.189 V and Epc at 0.254 V. In contrast, Cu(II) is reduced at a more positive potential and a decreasing current at the kanamycin SAM/Au electrode. Cu(II) and kanamycin can form a stoichiometry complex with chemical ratio of 2:1. The interaction of Cu(II)–kanamycin complex with calf thymus DNA is also studied in the solution. And the interactive mode between Cu(II)–kanamycin complex and DNA is verified by the fluorescence method. Binding constants (K) of the Cu(II)–kanamycin complex to DNA and binding site size (s) are calculated from voltammetric data and equal to 1.5 × 107 l/mol and 4 bp, respectively. [Copyright &y& Elsevier]

Based on the continuous wavelet transform (CWT), three types frequency spectra, wavelet frequency spectrum (WFS), point frequency spectrum (PFS) and time frequency spectrum (TFS), were developed. Two data sets were simulated and treated with the proposed spectra, the results indicated that WFS could extract the frequency information, which was like Fourier analysis but more accurate, PFS could obtain the frequency at any moment, TFS could show frequency change with time. These abilities of PFS and TFS were impossible for Fourier analysis. An oscillating chemical signal was processed with WFS and TFS. From the processed results, two points could be learned about the oscillating chemical reaction: one was the oscillating chemical reaction was a mixture one including two or more complex kinetics processes, the velocity of the switch from the reduced state (RS) to the oxidized state (OS) was faster than the reverse switch (from OS to RS); the other was increase of KBrO3 could decrease the velocities of both switches, which led to the oscillating period became longer. [Copyright &y& Elsevier]

A gold electrode modified by 5-{[4-(4-mercapto)phenylmethoxy]phenyl}-10,15,20-tris(phenyl)porphyrin cobalt(II) (MPPTPCo(II)) has been prepared. The properties of the modified electrode were investigated by scanning electronic microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) as well as electrochemical methods. The MPPTPCo(II)-SAM (SAM: self-assembled monolayer) modified electrode could successfully be used for the electrocatalytic oxidation of ascorbic acid (AA). The catalytic currents increased linearly with AA concentration in the range of 1.2×10−8–3.9×10−5 mol l−1 with the correlation coefficient of 0.9944. The detection limit was 2.6×10−9 mol l−1 with 10 min accumulation. [Copyright &y& Elsevier]

The insertion of Co(II) into a thiol-derivatized free-base porphyrin monolayers pre-assembled on gold has been conducted by refluxing the Co(II) solution in which the monolayer-coated gold electrode was immersed. The monolayers have been used for the electrocatalytic oxidation of ascorbic acid (AA). A large decrease (ca. 243 mV) in the overpotential for the oxidation of AA has been observed at the self-assembled monolayer modified Au electrode. Catalytic currents increased linearly with AA concentration in the range of 8.2 x 10[sup -8]-3.9 x 10[sup -4] mol/L with the correlation coefficient of 0.9948. The detection limit was 4.6 x 10[sup -9] mol/L. The modified electrode exhibited good sensitivity and stability. The proposed method was applied to the determination of AA in real samples with satisfactory results. [ABSTRACT FROM AUTHOR]

The interaction of the two new synthesized transition-metal complexes, ML2 (M=Co, Cu, L=1,8-dihydroxyethyl-1, 3,8,10,13-hexa-azacyclotetradecane) with calf thymus DNA was probed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Adding deoxyribonucleic acid (DNA) into [CoL]2+ and [CuL]2+ solution, the ip value of all the peaks of [CoL]2+ and [CuL]2+ significantly decreased in proportion to concentration of DNA. Glassy carbon electrodes (GCEs) were modified with DNA by adsorption, and it was electrochemically characterized with transition-metal complexes, [ML]2+. The DNA modification layer on the GCE is unstable to alkali and to heat, but stable to acid solutions and very stable in long stock in a dry state. It could be seen that peak potential shifted positively and the peak current increased significantly. The electrochemical parameters, binding constant (kn+) and binding sites(s) were calculated by a nonlinear regression method. [Copyright &y& Elsevier]

The synthesis and characterization of three new unsymmetrical porphyrins and their Co(II) complexes are reported. The method that is used by synthesizing the porphyrins has not previously been reported. Structural assignment of the porphyrins and their Co(II) complexes is based on the elemental analysis, UV-Vis, IR, and 1H NMR spectra. [ABSTRACT FROM AUTHOR]

An electrochemical investigation for rutin on glassy carbon electrode is presented. An adsorptive process is observed. The maximum coverage on the electrode surface is 5.09 × 10[sup -10] mol/cm², this area corresponding to a benzene ring with 3',4'-dihydroxides adsorbed on the electrode surface; the other parts of rutin keep away from the surface. In the meantime, a new electrochemical method for determining rutin is presented. In a medium of 0.1 M acetate buffer solution (pH = 4.46), a very sensitive polargraphic adsorptive wave is observed by using a differential pulse voltammetry at about 0.29 V (vs. Ag/AgCl). The linear relationship between the peak current and the concentration of rutin exists in a range from 3.28 × 10[sup -7] to 3.28 × 10[sup -5] M. The detection limit of rutin is down to 2.51 × 10[sup -8] M. This method has been applied to determine rutin in several samples of Chinese medicines. The results are satisfactory. [ABSTRACT FROM AUTHOR]

The voltammetric detection of copper(II) was carried out at a carbon paste electrode (CPE) modified with tetraphenylporphyrin (TPP). The analysis procedure consisted of an open circuit preconcentration step in stirred sample solution. This was followed by medium exchange to a pure electrolyte solution (Britton-Robinson buffer pH = 6) where the accumulated copper(II) was reduced at -0.8 V vs. Hg/Hg[sub 2]SO[sub 4] and subsequently an anodic potential scan was effect to obtain the voltammetric peak. The parameters and conditions such as pH of the analyte solution and supporting electrolyte, preconcentration time, CPE composition, its activation and regeneration, and others, were studied in detail. The detection limit of the proposed procedure was found to be 2.0 × 10[sup -9] mol 1[sup -1] of Cu(II) in the analyte solution for a preconcentration time of 12 min. Applying suitable preconcentration times, a linear calibration graph from 9.0 × 10[sup -8] to 5.0 × 10[sup -5] mol 1[sup -1] of Cu(II) was established. Multiple determinations (n = 8), following a preconcentration-measurement-regeneration cycle, gave a relative standard deviation of 4.5% at Cu(II) concentration of 1.0 × 10[sup -7] mol 1[sup -1]. The proposed method was applied to the determination of Cu(II) in a real sample of residue solution after extraction and a mineral sample of Jinchuan Corporation. [ABSTRACT FROM AUTHOR]

Organic contamination of water results in significant risks to the biosphere and human health. The treatment of organic pollutants found in effluents urgently requires a green, sustainable, and effective approach. Herein, a straightforward one-step procedure was developed to create a photocatalytic mesh using iron mesh as the substrate and the g-C3N4/MIL-101(Fe) heterostructure as the photocatalytic material to activate persulfate (PS) for the removal of methyl orange (MO) from water. Fluorescence stereo microscopy (FSM), scanning electron microscopy (SEM), nitrogen adsorption–desorption, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray powder diffraction (XRD) were used to characterize the morphological and physicochemical properties of the synthesized composites, which confirmed the successful growth of g-C3N4/MIL-101(Fe) on the iron mesh. The outstanding PS activation capacity of g-C3N4/MIL-101(Fe) promoted electron transfer and accelerated the generation of SO4˙−, resulting in up to 91.05% MO degradation under 60 min of visible light exposure. The removal mechanisms were investigated by quenching experiments and electron spin resonance (ESR), which proved that ˙OH, ˙O2− and h+ contributed to the removal of MO. Moreover, the degradation pathways of MO and the as-formed intermediates were identified by high-resolution mass spectroscopy (HRMS). This study provides a convenient and economical method to build innovative photocatalytic systems for organic pollutant degradation. [ABSTRACT FROM AUTHOR]

Efficient activation of hydrogen peroxide (H2O2) through biomimetic catalysis still faces a major challenge. In this work, inspired by the catalytic pocket of natural peroxidase, Cu single atom (CuSA) and AuCu nanoparticles (AuCuNPs) anchored on nitrogen‐doped carbon skeleton (CuSA‐AuCuNPs/NC) serve as dual active sites that significantly accelerate the charge transfer process and thus achieve efficient H2O2 activation. Meanwhile, the experimental and theoretical calculations show that the well‐established electronic communication effect between CuSA and AuCuNPs results in moderate electronic modifications to CuSA, which promotes the heterolysis of H2O2 and the timely desorption of H2O. As a proof of concept, CuSA‐AuCuNPs/NC show remarkable performance in detecting uranyl ions in seawater. This work provides new insights into the H2O2 activation for colorimetric sensing. [ABSTRACT FROM AUTHOR]

A facile carbon radical reaction procedure and a chemical reduction method were proposed to synthesize Ag nanoparticles on functionalized graphene with uniform, high dispersion and excellent stability. The resultant material showed excellent electrocatalytic activity to nitroaromatic compounds and high sensitivity to the detection of nitroaromatic compounds. [ABSTRACT FROM AUTHOR]

Non-technical losses (NTL) caused by fault or electricity theft is greatly harmful to the power grid. Industrial customers consume most of the power energy, and it is important to reduce this part of NTL. Currently, most work concentrates on analyzing characteristic of electricity consumption to detect NTL among residential customers. However, the related feature models cannot be adapted to industrial customers because they do not have a fixed electricity consumption pattern. Therefore, this paper starts from the principle of electricity measurement, and proposes a deep learning-based method to extract advanced features from massive smart meter data rather than artificial features. Firstly, we organize electricity magnitudes as one-dimensional sample data and embed the knowledge of electricity measurement in channels. Then, this paper proposes a semi-supervised deep learning model which uses a large number of unlabeled data and adversarial module to avoid overfitting. The experiment results show that our approach can achieve satisfactory performance even when trained by very small samples. Compared with the state-of-the-art methods, our method has achieved obvious improvement in all metrics. [ABSTRACT FROM AUTHOR]

ZnO quantum dots (QDs) supported on porous nitrogen-doped carbon (ZnOQDs/P-NC) exhibited excellent electrochemical performance for the electroreduction of CO2 to CO with a faradaic efficiency of 95.3% and a current density of 21.6 mA cm−2 at −2.2 V vs. Ag/Ag+. [ABSTRACT FROM AUTHOR]

A rapid and highly selective naked-eye detection of hydrochloric acid (HCl) in an aqueous medium was established using HCl-triggered redispersion of gold nanoparticle aggregates. [ABSTRACT FROM AUTHOR]

The triazine‐based covalent organic frameworks (tCOF), an intriguing subtype of COFs, are expected as highly promising photocatalysts for various photocatalytic applications owing to their fully conjugated structures and nitrogen‐rich skeletons. However, the inherent hydrophobicity and fast recombination of photoexcited electron‐hole pairs are two main factors hindering the application of tCOF in practical photocatalytic reactions. Here, a post‐synthetic modification strategy to fabricate superhydrophilic tCOF‐based photocatalysts is demonstrated by in situ growing FeOOH clusters on TaTz COF (TaTz‐FeOOH) for efficient photocatalytic oxidation of various organic pollutants. The strong polar FeOOH endows TaTz‐FeOOH with good hydrophilic properties. The well‐defined heterogeneous interface between FeOOH and TaTz allows the photoelectrons generated by TaTz to be consumed by Fe (III) to transform into Fe (II), synergistically promoting the separation of holes and the generation of free radicals. Compared with the unmodified TaTz, the optimized TaTz‐FeOOH (1%) shows excellent photocatalytic performance, where the photocatalytic degrade rate (k) of rhodamine B is increased by about 12 times, and the degradation rate is maintained at 99% after 5 cycles, thus achieving efficient removal of quinolone antibiotics from water. This study provides a new avenue for the development of COF‐based hydrophilic functional materials for a wide range of practical applications. [ABSTRACT FROM AUTHOR]

Background: Iron oxide nanocomposites have received a great attention for their application in various fields like physics, medicine, biology, and material science etc., due to their unique properties, such as magnetism, electrical properties, small size, biocompatibility and low toxicity. Methods: Fe3O4/Ag3PO4@WO3 nanocomposites with different weight percent of Ag3PO4 were successfully prepared through fabricated Ag3PO4/Fe3O4 with WO3 via in situ fabrication method, electrospinning involved precursor solution preparation and spinning to enhance photocatalyst performance under simulated sunlight for the degradation of methylene blue (MB) and antibacterial activity against Staphylococcus aureus (S. aureus). Results: The photocatalytic degradation of methylene blue (MB) under simulated light irradiation indicated that the nanocomposite with 0.25 mg of Ag3PO4 has the best activity. An additional advantage of these photocatalysts is magnetic recoverability, using external magnetic field and photocatalytic stability of the nanocomposites was evaluated for three cycles. In addition, using different scavengers, holes (h+) and superoxide radical (O2·−) radicals and hydroxide radical (·OH) were identified the main oxidative species in the degradation reaction of methylene blue. Conclusions: The results reveal that Fe3O4/Ag3PO4@WO3-0.25 nanocomposites have photocatalytic and antibacterial activity against S. aureus. The photocatalyst and mechanism based on the enhancement of electron transfer processes between Ag3PO4 and WO3 nanoparticles. [ABSTRACT FROM AUTHOR]

The precisely modulated synthesis of programmable light‐emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene‐based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation–induced electrochemiluminescence (PI‐AIECL) systems. The best‐performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2′‐bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six‐fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL‐based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high‐performance aggregation‐induced electrochemiluminescence emitters. [ABSTRACT FROM AUTHOR]

The precisely modulated synthesis of programmable light‐emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene‐based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation–induced electrochemiluminescence (PI‐AIECL) systems. The best‐performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2′‐bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six‐fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL‐based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high‐performance aggregation‐induced electrochemiluminescence emitters. [ABSTRACT FROM AUTHOR]

An effective ratiometric fluorescent probe based on silicon particles/gold nanoclusters (SiNPs/AuNCs) nanohybrid has been fabricated and applied to be a "on-off-on" switch sensing platform for detection of Hg2+ and cysteine. In this elaborated sensing platform, the SiNPs just acted as internal reference signal, providing a build-in correction for background interferences and environmental effects, to which the AuNCs as a signal report unit for Hg2+ response was covalently grafted by amidation reaction. The fluorescence intensity of SiNPs/AuNCs could be effectively quenched upon adding Hg2+, accompanied with an easily distinguishable fluorescent color change. The ratiometric fluorescence signal (F 649 /F 511) of the established nanoprobe was linearly proportional to the concentration of Hg2+ ranging from 0.02 to 24 μM with a low detection limit of 5.6 nM, which is below the guideline value of Hg2+ in drinking water set by the World Health Organization. Interestingly, upon addition of cysteine, the Hg2+-quenched fluorescence intensity was recovered gradually. Furthermore, the approach developed has also been utilized for Hg2+ detection in real complex biological samples with satisfactory results. More importantly, benefiting from the good water-solubility and excellent biocompatibility, this nanoprobe can monitor the intracellular Hg2+ and cysteine in living cells, indicating its potential applications in advanced biosensing and bioimaging. Herein, we reported an effective dual-emission ratiometric probe for "on-off-on" detection of Hg2+ and cysteine. Image 1 • An efficient dual-emission fluorescent probe for simultaneously and visual detecting Hg2+ and L-Cys was constructed. • The probe could simultaneously detection of Hg2+ in human serum and urine samples. • Due to the ratiometric fluorescence model, the background interference was extincted. • The developed probe was successfully used for the fluorescence bioimaging of Hg2+ and L-Cys in live cells. [ABSTRACT FROM AUTHOR]

BV/In 2 O 3 /FeNi photoanode was rational designed and constructed by impregnation annealing and electrodeposition method. A stable photocurrent of 4.0 mA cm−2 was achieved at 1.23 V RHE under AM 1.5 G (100 mW cm−2), which can be ascribed to the synergistic effect of heterojunction structure and cocatalyst loading. [Display omitted] Bismuth vanadate (BiVO 4) is a promising nanomaterial for photoelectrochemical (PEC) water oxidation. However, the serious charge recombination and sluggish water oxidation kinetics limit its performance. Herein, an integrated photoanode was successfully constructed by modifying BiVO 4 (BV) with In 2 O 3 (In) layer and further decorating amorphous FeNi hydroxides (FeNi). The BV/In/FeNi photoanode exhibited a remarkable photocurrent density of 4.0 mA cm−2 at 1.23 V RHE , which is approximately 3.6 times larger than that of pure BV. And the water oxidation reaction kinetics has an over 200% increased. This improvement was mainly because the formation of BV/In heterojunction inhibited charge recombination, and the decoration of cocatalyst FeNi facilitated the water oxidation reaction kinetics and accelerated hole transfer to electrolyte. Our work provides another possible route to develop high-efficiency photoanodes for practical applications in solar conversion. [ABSTRACT FROM AUTHOR]

Bismuth vanadate (BiVO4) has been considered a promising photoactive material in photoelectrochemical (PEC) water-splitting systems. However, the performance of BiVO4-based photoanodes is currently unsatisfactory, indicating the need for new architectural designs to improve their efficiency. In this paper, a porphyrin-phosphazene polymer (THPP-HCCP) was synthesized with a sizeable conjugated structure, and Ag particles were deposited on its surface as an organic–inorganic composite interface improvement layer. The deposition of the composite polymer film on BiVO4 resulted in a significant increase in photocurrent density, reaching up to 2.2 mA cm−2 (1.23 V vs. RHE), almost three times higher than pristine BiVO4, which benefits from the synergistic effect of Ag nanoparticles and porphyrin-phosphazene. Furthermore, photophysical and intensity-modulated photocurrent analysis demonstrated that the Ag–THPP-HCCP heterostructures could broaden the light-absorbing range and facilitate hole transfer to the semiconductor surface, resulting in an improved water oxidation process. The dynamic charge transport behavior of Ag–THPP-HCCP/BiVO4 was investigated using scanning photoelectrochemical microscopy, which showed that the rate constant (Keff) exhibits an almost 4-fold increase compared to pristine BiVO4, indicating a significant improvement in the transport of photogenerated holes. This experiment presents a novel strategy for designing high-efficiency polymer-based photoanodes. [ABSTRACT FROM AUTHOR]

A novel and tunable synthesis of Fe/CuOx bimetallic catalysts has been achieved via a simple Fe-precipitation and calcination method, which was used for highly efficient CO2 electroreduction to control the wide-ranging CO to H2 ratio by simply changing the ratio of metals. The faradaic efficiency of CO could reach 86.1% with a current density of 49.1 mA cm−2. The ratio of CO/H2 could reach 1.94 to 6.18 and it was discovered that the Fe/CuOx bimetallic catalysts could easily get different ratios of syngas, which can be applied directly in industry. [ABSTRACT FROM AUTHOR]

This paper proposes a new hybrid magnet (HM) dual-stator vernier machine (DSVM) with flux-reversal (FR) magnet arrangement, in which NdFeB and ferrite magnets are reversely mounted on tooth tips of outer and inner stators, respectively. The hybrid dual excitation topology enhances the magnetic fields of inner and outer air-gaps, which are modulated by the rotor composed of iron poles. The proposed topology, operating principle, and design consideration are described. The merits of the proposed HM-FRDSVM are verified when compared to the same FRDSVMs with dual NdFeB magnet excitation and with dual ferrite magnet excitation and the conventional dual stator synchronous permanent magnet machine. The two-dimensional finite element analysis results show that the proposed machine has high torque cost performance with low torque ripple and low cogging torque that are desirable for large telescope drive application. [ABSTRACT FROM AUTHOR]

The electrochemical nitrogen reduction reaction (NRR) has the potential to replace the Haber–Bosch process for ammonia synthesis under ambient conditions. However, the selectivity and yield of the NRR are impractical, owing to the preferential binding of the electrocatalyst to H and the consequential coverage of active sites. In this study, VO2, with N2 strongly adsorbed over H atoms, is used as a support to provide a N2 source to avoid the hydrogen evolution reaction. Mo, with a high NRR activity, is introduced as the active site to promote the NRR. Meanwhile, the electronic metal–support interaction between the support and Mo creates electron‐deficient sites, which weakens H adsorption and lowers the energy barrier of the first step, protonation, thereby kinetically enhancing the NRR activity. The average NH3 yield of Mo/VO2 is 190.1 µgNH3 mgcat.−1 h−1 and the Faradaic efficiency is 32.4% at −0.5 V versus reversible hydrogen electrode, which is 10.8 and 2.8 times greater than that of VO2, respectively. [ABSTRACT FROM AUTHOR]

In this study, a carboxylated carbon nanotube-grafted Ag3PO4@AgIO4 (CNT-COO−/Ag3PO4@AgIO4) composite was synthesized through an in situ electrostatic deposition method. The synthesized composite was characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), and energy-dispersive X-ray spectroscopy (EDS). The electron transfer ability of the synthesized composite was studied using electrochemical impedance spectroscopy (EIS). The CNT-COO−/Ag3PO4@AgIO4 composite exhibited higher activity than CNT/Ag3PO4@AgIO4, Ag3PO4@AgIO4, and bare Ag3PO4. The material characterization and the detailed study of the various parameters thataffect the photocatalytic reaction revealed that the enhanced catalytic activity is related to the good interfacial interaction between CNT-COO and Ag3PO4. The energy band structure analysis is further considered as a reason for multi-electron reaction enhancement. The results and discussion in this study provide important information for the use of the functionalized CNT-COOH in the field of photocatalysis. Moreover, providinga new way to functionalize CNT viadifferent functional groups may lead to further development in the field of photocatalysis. This work could provide a new way to use natural sunlight to facilitate the practical application of photocatalysts toenvironmental issues. [ABSTRACT FROM AUTHOR]

Fiber‐based electronics technology has been making significant strides towards applicable emergence into many fields. One such field is the use of fiber‐based electronics in the development of smart textiles. Here, we report the use of stretchable styrene‐ethylene‐butylene‐styrene (SEBS) fibers as a conductive substrate to simultaneously load Au nanowire and Prussian blue (PB) as biosensing interfaces. Accordingly, due to the synergistic catalytic effect between Au nanowire and Prussian blue, the as‐obtained flexible PB/Au fibers can not only show the potential as wearable biosensors but also serve as high‐performance peroxidase‐like nanozymes. The functional fibers can be used for colorimetric detection of H2O2 and uric acid, exhibiting satisfactory sensitivity and selectivity in serum sample analysis. The flexible PB/Au fibers represent a new form of Peroxidase‐like nanozymes, which could open doors to various wearable biosensing applications. [ABSTRACT FROM AUTHOR]

Tyrosine is the precursor of some neurotransmitters such as thyroxine and dopamine. It has the effect of regulating emotions and stimulating the nervous system. Changes in tyrosine levels in the human body are associated with certain diseases. Therefore, it is very necessary to prepare a new type of tyrosine sensor. In this work, an enzyme-free electrochemical sensor based on MXene/CNTs/CuMOF composite was developed for the detection of tyrosine. Embedding carbon nanotubes (CNTs) into MXene effectively prevented the aggregation of MXene sheets. Further modification of MXene/CNTs materials with CuMOF octahedral particles with porous structure can improve the porosity and catalytic capability of the composites. Under the optimal detection conditions, the prepared sensor has good linearity in the detection of tyrosine within range 0.53 μM–232.46 μM with a limit of detection (LOD) of 0.19 μM. The stability and selectivity of the sensor is high, and can be used to detect tyrosine in human serum. [Display omitted] [ABSTRACT FROM AUTHOR]

The rapid advancement of science and technology has led to the development of electronic devices that require higher energy storage capacities. Because of their greater energy as well as power density capabilities, hybrid supercapacitors offer an answer to the problems that result from the limitations of both supercapacitors and batteries when it comes to power densities and energy density. Borate ion-functionalized nickel manganese hydroxide nanoparticles (denoted as NiMnB) were prepared by a simple chemical reduction method, and novel complexes were obtained by growing NiMnB with a core-shell structure on reduced graphene oxide (rGO). The NiMnB inner core facilitates electron transport, while the borate/metal borate shell layer on the outer layer aids in OH- absorption. Additionally, rGO integrates the dispersed nanoparticles, resulting in a comprehensive conductive system. This design optimizes the electrochemical performance of NiMn-based electrodes. The specific capacitance of the NiMnB/rGO-16 electrode was 916 F g−1 when tested at a current density of 1 A g−1. NiMnB/rGO-16 was used as the positive electrode and activated carbon (AC) as the negative electrode assembled the hybrid supercapacitor. It showed strong cycling stability and an energy density of 50.2 Wh kg−1. [Display omitted] • Electrode materials with core-shell morphology (NiMnB/rGO) were successfully prepared by chemical reduction method. • NiMnB/rGO-16 electrode shows high specific capacitance of 916 Fg−1 at a current density of 1 A g−1. • The NiMnB/rGO-16//AC device exhibits a high energy density of 800.4 Wkg−1,50.2 Wh kg−1. • NiMnB/rGO-16//AC maintains 86.3 % of initial capacitance after 8000 cycles at 5 A g−1. [ABSTRACT FROM AUTHOR]

• A metal-free graphitized carbon nitride (g-C 3 N 4) nanosheets was synthesized by gas template method. • The surface area and photocurrent of nanosheets was 6 and 3 times than that of bulk g-C 3 N 4 , respectively. • The nanosheets showed superior photodegradation ability towards cefixime. • 99% of cefixime could be removed within 30 min under the sunlight and persulfate addition. The removal and the treatment of antibiotics in environmental water by advanced oxidation process (AOP) has attracted much attention. In this paper, a metal-free graphitized carbon nitride nanosheets (g-C 3 N 4 -NS) was synthesized by gas template method. Cefixime in water was removed by direct photocatalysis and activation of persulfate (PS) under simulated sunlight. The flaky morphology made g-C 3 N 4 -NS's band gap narrow, charge separation enhanced, light absorption enhanced, and more active sites were exposed. The specific surface area of g-C 3 N 4 -NS was about 6 times than that of bulk g-C 3 N 4 , and its photocurrent was about 3 times. The effects of different PS concentrations and pH values on photocatalytic activation in two ways were studied. The influence of anions on the removal of cefixime was also studied. The synthesized g-C 3 N 4 -NS has good stability, and its performance is well maintained after continuous photocatalysis and photoactivation catalysis. The degradation rate of cefixime by g-C 3 N 4 -NS was three times than that of bulk g-C 3 N 4 , and the removal rate of cefixime by g-C 3 N 4 -NS /PS system was 30 times than that of PS. This work provides advanced idea for metal-free AOP in environmental chemistry. [ABSTRACT FROM AUTHOR]