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This article proposes an adaptive model-free deadbeat predictive current control (MF-DPCC) algorithm for achieving high-performance current control of non-contact integrated permanent magnet vernier motors (NIPMVMs). To address the issue that traditional extended state observer-based deadbeat predictive control (ESO-DPCC) still relies on motor models and parameters, an ultralocal model is introduced to design a model-free current controller. Furthermore, to address the issue that initial gain of the controller depends on the inductance parameter, a gain-adaption algorithm based on the deadbeat characteristic is proposed. In addition, considering the effect of dead-time, a dual-amplitude signal with extremely low duty and amplitude levels has been adopted to improve the adaptive precision of the gain and to achieve deadbeat control of NIPMVMs. The validity of the proposed MF-DPCC is confirmed through experiments conducted on an NIPMVM platform. [ABSTRACT FROM AUTHOR]

This article proposes an improved model-free deadbeat predictive current control (MFCC) method for permanent magnet synchronous motors (PMSMs) based on the ultralocal model and H∞ norm. Firstly, the traditional deadbeat predictive current control (DPCC) method is introduced and a theoretical analysis is conducted on its sensitivity to parameters. Building upon this, the limitations of model dependence and the limited robustness of the deadbeat predictive current control method based on the extended state observer (ESO-DPCC) are theoretically analyzed. Furthermore, an improved MFCC method based on the ultralocal model is proposed, and the influence of the observer on MFCC is theoretically analyzed. This study combined the proposed method with the H∞ norm, and the optimal coefficients of the observer were tuned to enhance the robustness and dynamic performance of the current loop. Finally, the proposed algorithms were validated on a 400 W PMSM platform. [ABSTRACT FROM AUTHOR]

To meet the environmental protection and flame retardancy requirements for epoxy resins (EPs) in certain fields, in this study, a novel triazine-ring-containing DOPO-derived compound (VDPD), derived from vanillin, 2,4-Diamino-6-phenyl-1,3,5-triazine, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), was synthesized using a one-pot method. Flame-retardant epoxy resin (FREP) was prepared by adding various ratios of VDPD to EP and curing with 4,4-diaminodiphenylmethane (DDM). The curing behavior, thermal stability, mechanical properties, and flame-retardant properties of the FREP were examined in various tests. According to the results, when the amount of VDPD added to the EP increased, the glass transition temperature of the FREP decreased linearly, and the flame-retardant properties gradually improved. With a 0.4 wt.% P content, the vertical burning rating of EP/DDM/VDPD-0.4 (according to the theoretical content of VDPD) reached the V-0 level, and the LOI value reached 33.1%. In addition, the results of a CCT showed that the peak heat release rate (PHRR) of EP/DDM/VDPD-0.4 decreased by 32% in comparison with that of the EP. Furthermore, compared with those of the EP, the tensile strength of EP/DDM/VDPD-0.4 decreased from 80.2 MPa to 74.3 MPa, only decreasing by 6 MPa, and the tensile modulus increased. Overall, VDPD can maintain the mechanical properties of EP and effectively improve its flame-retardant properties. [ABSTRACT FROM AUTHOR]

In this article, a stator flux oriented sensorless control method is proposed for interior permanent magnet synchronous motor (IPMSM) drives based on the direct torque and flux control (DTFC) and pseudo-random high-frequency signal injection (PR-HFSI) in the zero-low speed range. The DTFC for IPMSMs is introduced briefly and the conventional high-frequency signal injection (HFSI) method, which requires an additional transformation, is also introduced. Then the stator flux oriented PR-HFSI is proposed comprising injection mode and rotor observation, with the aim of noise reduction and easy implementation. Furthermore, the high-frequency noise in HFSI and the mechanisms of noise suppression in PR-HFSI are analyzed based on current spectrums. Meanwhile, the optimal noise reduction frequency combination of n kinds frequency injections is also analyzed. Finally, the performance of the proposed stator flux oriented PR-HFSI method is confirmed with experiments on a 60 kW IPMSM test bench. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Metal organic frameworks have been employed as high‐performance layered double hydroxide (LDH) composite supercapacitor electrode materials but have shown unsatisfactory redox ability and stability. Herein, a host‐guest CuMo‐based polyoxometalate‐based metal organic framework (POMOF) with copious electrochemically active sites and strong electrochemical redox activities has been effectively coupled with POM‐incorporated CoNi‐LDH to develop a nanocomposite (NENU‐5@CoNi‐LDH) by a simple solvothermal method. The designed electrode shows a high specific capacity of 333.61 mAh·g–1 at 1 A·g–1. In addition, the novel hybrid symmetric supercapacitor NENU‐5@CoNi‐LDH/active carbon (AC) demonstrated a high energy density of 80.8 Wh·kg–1 at a power density of 750.7 W·kg–1. Interestingly, the nanocomposite of NENU‐5@CoNi‐LDH exhibits an outstanding capacitance retention of 79% after 5000 charge‐discharge cycles at 10 A·g–1. This work provides a new strategy and will be the backbone for future energy storage research. [ABSTRACT FROM AUTHOR]

This article proposes a pseudo-random high-frequency triangular-wave current signal injection (PR-HFTCI) based sensorless control scheme for synchronous reluctance motor (SynRM) drives at zero-low speed domain to suppress the high-frequency (HF) loss and the HF audible noise which are introduced by the significant nonlinearities of SynRMs and the traditional constant amplitude HF square-wave voltage injection method. The pseudo-random HF triangular-wave current signal with random frequency and random phase is injected to eliminate the discrete spectrum of the current power spectra density (PSD) and the corresponding current PSD analysis is performed to evaluate it. In addition, the HF component amplitude of the d-axis voltage reference can be adjusted adaptively with the variation of load to maintain the HF current amplitude constant, it is easy to implement and does not require any extra regulator and signal processing. Hence, the HF loss and the HF torque ripple can be effectively reduced under the heavy load. Finally, the effectiveness and the correctness of the proposed PR-HFTCI based sensorless control scheme are validated with experiments on a 1.5-kW SynRM drive platform. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the whole plant of Paraboea rufescens led to the isolation of a new compound Paraboside C (1) and eight known compounds, which including two phenylpropanoid glycosides (2 and 3), two glycosides (4 and 5), three triterpenoids (6–8), and one ethyl cyclohexanol derivative (9). Their structures were elucidated based on extensive spectroscopic methods (NMR, MS, UV, IR and ECD experiments) and comparison with literature data. Compounds 2 and 5 exhibited significant neuroprotective activities against corticosterone induced PC12 cells, which presenting a dose-dependent effect. The chemotaxonomic significance of the isolated compounds were also been discussed. [Display omitted] • 9 compounds were isolated from the whole plant of Paraboea rufescens. • Compound 1 was a new phenylpropanoid glycoside. • Compounds 3 – 9 were isolated from P. rufescens for the first time. • Compounds 2 and 5 exhibited significant neuroprotective activities. • The chemotaxonomic significance of the isolated compounds were discussed. [ABSTRACT FROM AUTHOR]

• The rupture process of the 2014 M w 6.2 Ludian earthquake was constrained by teleseismic data and more strong-motion data. • The Ludian earthquake ruptured two conjugate faults with strike angles of 77° and 160°, respectively. • The rupture simultaneously took place on two conjugate faults and lasted approximately 10 s. • The shallow dominating slip patch is the main reason for the enormous disaster from the earthquake source perspective. The M w 6.2 Ludian earthquake, struck Yunnan, China on August 3rd, 2014, leading to a complex aftershock distribution and enormous disaster. The Ludian earthquake is well recorded by the China Earthquake Network. The rupture process of the Ludian earthquake is constrained by the more local strong motion data including the LLT station with epicentral distance of ∼2 km and teleseismic body waves and surface waves in this study. The local strong motion data constrained the epicenter's location and rupture process better. Waveform fit of key local strong-motion stations supported that the Ludian earthquake ruptured two conjugate faults with strike angles of 77° and 160°, respectively. The rupture simultaneously took place on two conjugate faults and lasted approximately 10 s. The peak slip, rise time, and average slip rate are 0.63 m, 0.69 s, and 2.12 m/s, respectively. The result shows that the main rupture zone was on the fault with a strike of 160°. The depth of the major slip patch was 0–4 km with a centroid depth of 2 km. It indicates that the shallow slip is the main reason for the enormous disaster from the earthquake source perspective. [ABSTRACT FROM AUTHOR]

Chemical investigation on the fruits of Zanthoxylum motuoense have led to the isolation of a new flavonolignan (1), together with three known flavonoids (2 - 4), as well as five alkylamides (5 – 9). Their structures were determined by NMR, IR, UV, CD spectra and HRESIMS data. The chemotaxonomic significance of these compounds was discussed. The neuroprotective activity of the isolated compounds were evaluated. Compound 6 showed a significant protective effect against corticosterone-induced neuronal damage at 20 μmol/L. [Display omitted] • Nine compounds were isolated from the fruits of Zanthoxylum Motuoense. • Compounds 1 was identified as a new flavonolignan. • All the compounds were isolated from Z. motuoense for the first time. • Alkylamides could be recognized as a typical biomarker for Zanthoxylum genus and Rutaceae family. [ABSTRACT FROM AUTHOR]

To establish a fast and simple quantitative method for detection of heart-type fatty acid-binding protein (H-FABP) in serum based on a background fluorescence quenching immunochromatographic assay. A detection card based on the double-antibody sandwich double-antibody method with background fluorescence quenching was developed for quantitative measurement of H-FABP in serum. The optimal concentrations of control for coating the test and control lines were determined as well as the concentrations of gold-labeled antibodies used in preparing the detection system. The detection method for H-FABP in serum was established and validated using real-world clinical samples. The optimal concentrations of labeling antibody and coating antibody were 5.0 μg/mL and 1.0 mg/mL, respectively. The test card had a sensitivity of 1.15 ng/mL over a linear concentration range of 0–100 ng/mL. Based on three batches prepared for testing the card, the relative standard deviation (RSD) within batches was less than 15% without a significant difference (P=0.942). The detection method was tested against common interfering substances in serum, such as bilirubin, triglyceride and serum anticoagulants ethylenediamine tetraacetic acid (EDTA), heparin, and sodium citrate, and no significant cross-reaction was detected. The test method was further validated with 50 clinical serum samples, and the test results were comparable with standard reference detection methods with good correlation (R=0.95). Our study presents a new method with strong specificity and sensitivity for the detection of H-FABP in serum, which could promote H-FABP detection in a broad range of applications. [ABSTRACT FROM AUTHOR]

The phytochemical study on the whole plant of Lobelia davidii Franch. (Campanulaceae) resulted in the isolation of one new polyacetylene, davidiotylin A (1), one new natural compound, (5 R) N -methyl-5-acetophenone-pyrrolidine-2-one (6), along with six known compounds including lobetyolin (2), choushenpilosulyne A (3), lobetyol (4), fissistigmol A (5), pistaciamide (7), N , N′ -dicoumaroylputrescine (8). Their structures were characterized by the comprehensive analysis of their NMR, IR, UV, ECD spectra and HRESIMS data. All the isolated compounds were reported from L. davidii for the first time. The chemotaxonomic significance of these compounds was discussed. [Display omitted] • Eight compounds were isolated from the whole plant of Lobelia davidii Franch. • Compounds 1 was identified as a new polyacetylene. • Compound 6 was a new natural compound, and its absolute configuration was determined by ECD spectrum. • All compounds were isolated from L. davidii for the first time. • The chemotaxonomic significance of the isolated compounds was discussed. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the whole plant of Paraboea rufescens led to the isolation of 17 compounds including nine phenylethanoid glycosides (1 – 9), two steroids (10 – 11), two triterpenoids (12 – 13), two dihydroflavones (14 – 15), and two organic acids (16 – 17). Their structures were elucidated by their spectroscopic data analysis. This is the first report of compounds from P. rufescens. The chemotaxonomic significance of P. rufescens and the other species among Gesneriaceae was also discussed. Phenylethanoid glycosides can be recognized as typical biomarkers for the genus Paraboea. • 17 compounds were first isolated from the whole plant of Paraboea rufescens. • Compounds 1 , 3 , 9 , 10 , 12 , and 14–16 were first isolated from the genus Paraboea. • Phenylethanoid glycosides can be recognized as typical biomarkers for the genus Paraboea. • Compounds 13 can serve as biomarkers for the family Gesneriaceae. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis between (NH )S O and MnSO was carried out to investigate the structure, morphology, and electromagnetic properties of Ni-doped MnO with different doping amounts. The samples were characterized by X-ray powder diffraction (XRD), X-ray fluorescence spectrometry (XRF), scanning electron microscopy (SEM), and vector network analysis. The analysis results revealed that all the final products were α-MnO and few amounts of γ-MnO , and the morphology changed obviously with the increase of the Ni doping amount. The doping of Ni had a certain effect on the electromagnetic properties, and some other properties derived from electromagnetic performances were also investigated, such as dielectric and magnetic loss tangent and microwave-absorbing properties. All the reflection loss (RL) peaks of the final products were moving toward lower frequency with increasing thickness, and with the thickness of 2 mm, the final products all had the maximum effective absorption bandwidth (RL < −10 dB), and the Ni-doped MnO had better reflection loss performance than the undoped MnO in the range of high frequency. [ABSTRACT FROM AUTHOR]

Analytical solutions for predicting spring-in angles of U-shaped composite parts generating in rubbery and glassy states are proposed. In the newly developed analytical solutions, the process-induced distortions of web and flange are mathematically converted to spring-in angles within the scope of small deformation theory, and then corresponding analytical expressions of web, corner, flange and total spring-in are separately derived. These new solutions can quantitatively give the correlation of web, corner, flange and total spring-in with material properties-related and geometrical configuration-dependent parameters, and evaluate the spring-in angles of multi-angle ply composite parts just using lamina properties. The reliability of newly proposed analytical solutions is checked by the comparison between the analytically calculated and experimentally measured spring-in angles for unidirectional and quasi-isotropic U-shaped composite parts. Meanwhile, numerical simulations on the U-shaped composite parts with various geometries and layups also provide a favourable agreement with analytical results. • Analytical solutions for spring-in of U-shaped composite parts are proposed. • New solutions can quantify effect of properties and geometry on spring-in angle. • New solutions can evaluate the spring-in angles just via lamina properties. • The reliability of solutions is experimentally and numerically validated. [ABSTRACT FROM AUTHOR]

The adaptive filters (ANF) have been commonly used in current harmonic suppression. However, the digital delay will narrow the stability region and its harmonic suppression performance will be deteriorated at high-speed region. To overcome this problem, this paper proposed two modified ANF. Combining with the deadbeat current (DBC) controller, the effect of digital delay on ANF is analyzed. A simple one step harmonic prediction method (OSPANF) is proposed to replace the traditional steepest gradient method (SGM). Based on the OSPANF, the current can be controlled stably in the high-speed area and the harmonic suppression effect is better than the traditional notch filter. Through bode diagram analysis, OSPANF will have a harmonic amplification peak near the set notch frequency, which may bring additional disturbances. Thus, a two steps prediction adaptive notch filter (TSPANF) is implemented. Through the Experimental results, it can be proved that the proposed TSPANF method has better harmonic suppression effect in the high-speed area than OSPANF and the stability region of the proposed two methods is larger than the traditional method. [ABSTRACT FROM AUTHOR]

The synergistic flame retardant system consisted of intumescent flame retardant (IFR) and organic modified attapulgite (OATP) synergist was used to improve the mechanical properties and flame retardancy of continuous glass fibre reinforced polyethylene composites (GFPE). The IFR was composed of ammonium polyphosphate (APP) as acid source and poly(1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (PDTBP) as carbon source. The mechanical properties (tensile strength) of GFPE/IFR/OATP were improved by 35%–43% after adding OATP synergist with rod-like fiber structure due to its strengthening and toughening effect on the resin matrix, and the flame retardancy increased first and then decreased with the increase of OATP synergist loading. When 4 wt% OATP synergist was added into GFPE/IFR, the LOI value increased from 29.5% to 31.3% and the flame spread rate significantly reduced. The synergistic flame retardant system of IFR/OATP could form a stable and dense char layer on the surface of glass fibre and weaken the wicking actions of glass fibre. The synergistic flame retardant system of 26 wt% IFR/4 wt% OATP could endow GFPE with best comprehensive performance. [ABSTRACT FROM AUTHOR]

Unidirectional laminated composite plate composed of AS4/8552 prepregs was manufactured with autoclave processing, and the bare and encapsulated FBG sensors were longitudinally embedded into the composite plate along the through-thickness direction to monitor the development of temperature and strain gradient. Before the measurement, the coefficient of temperature sensitivity and axial strain sensitivity of FBG sensors were calibrated, and the results reveal that the coefficient of axial strain sensitivity is a constant but coefficient of temperature sensitivity depends on the magnitude of temperature. Subsequent data analyses on the monitored results by encapsulated FBG sensors show that temperature distribution is relatively uniform inside composite plate but temperature gradient still exists in the through-thickness direction during curing. Meanwhile the monitored results by bare FBG sensors indicate that strain gradient also occurs during curing, and further investigation demonstrates that tool-part interaction is the major cause for the formation of strain gradient within the unidirectional composite plate. [ABSTRACT FROM AUTHOR]

A novel intumescent flame retardant (IFR) system composed of ammonium polyphosphate and poly (1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (APP/PDTBP) was mixed with polyethylene to prepare the continuous glass fibre reinforced polyethylene (CGF/PE) unidirectional prepregs by melt impregnation process, and then the CGF/PE/IFR composite laminate were consolidated by hot compression moulding method. The flame retardancy, thermal stability and mechanical properties of CGF/PE/IFR composite laminates were investigated by limiting oxygen index, vertical burning test, cone calorimetric test, thermogravimetric analysis, tensile and flexural strength tests, mode I interlaminar fracture toughness test, and scanning electron microscopy (SEM). The flame retardancy of CGF/PE composite laminates increased with the increase of IFR system loading, which attributes to the formation of intumescent char layer from flame retardants and the weakening of wicking actions of glass fibres. The mechanical properties increased and then decreased with addition of flame retardants, except for the flexural strength with continuous increase. The SEM images showed that IFR system had toughening effect and could improved the strength of fibre-matrix interface. Based on the mechanical properties and the flame retardancy, when the matrix contains 30 wt% IFR system, the CGF/PE/IFR composite laminate had the best comprehensive performance. Image 1 [ABSTRACT FROM AUTHOR]

This paper proposes a new flux control strategy for consequent-pole brushless hybrid excitation (CPBHE) machines to achieve a high efficiency and a fast convergence. Based on an analysis of the mathematical model of a CPBHE machine, a loss model of the CPBHE machine is derived, which demonstrates the feasibility of adopting d-axis flux to search for the optimal efficiency point. Furthermore, to improve the convergence speed of the online search algorithm and to make it suitable for the frequently varying operating conditions of electric vehicles (EVs), an adaptive step search algorithm based on the margin of the voltage limit combined with the offline table lookup method is proposed. Experimental results show that the proposed algorithm can optimize the efficiency of a motor system in the flux-weakening region and that it features a fast optimization process that makes it suitable for EV drives. [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) are regarded as highly efficient electrocatalysts due to highly active surface sites, electrical conductivity, and chemical stability, which result from the high electrocatalytic activity of the M-centers and P-sites. Thus, the aim of our work is to obtain highly efficient TMPs electrocatalysts by a facile and controllable strategy. We used N, S-rich Co/Fe bimetallic metal-organic framework as template to prepare ceramic Co/Fe binary phosphides embedded in N, S, O ternary-doped carbon matrix (CoFeP@NSOC). By means of a facile one-step low-temperature pyrolysis-phosphating approach, the optimized ceramic material CoFeP@NSOC-400 showed remarkable bifunctional electrocatalytic performances in an alkaline electrolyte, which only requires 176 and 240 mV overpotentials to achieve 10 mA cm−2 current density for HER and OER, respectively. Furthermore, when CoFeP@NSOC-400 is loaded on the highly conductive nickel foam (NF) for water splitting, it reaches a current density of 10 mA cm−2 at a low cell voltage of 1.62 V, superior to pure NF and other reported metal-phosphide electrocatalysts, at the same time, CoFeP@NSOC-400 shows negligible performance degradation and a relative current loss of only 4.3% for 40000 s continuous operations. These results indicate CoFeP@NSOC derived by MOFs through pyrolysis-phosphating is an ideal electrocatalysts for energy conversion applications. Nanostructured Co/Fe binary phosphides embedded in N, S, O ternary-doped carbon matrix by facile one-step low-temperature pyrolysis-phosphating approach from a N, S-rich bimetallic MOF to drive water splitting. By adjusting the phosphating temperature, the optimum CoFeP@NSOC-400 exhibits excellent bifunctional electrochemical performances for HER and OER in an alkaline electrolyte. When CoFeP–NSOC-400 is loaded on the foamed nickel for water splitting, a lower voltage 1.62 V is obtained to reach a current density of 10 mA cm−2. This paper proposes a one-step and low-cost phosphating method to obtain nanostructured bimetallic phosphides containing heteroatom doping carbon matrix, showing prominent electrocatalytic performance for water splitting. [Display omitted] • MOFs-derived Co/Fe TMPs embedded in N, S, O ternary-doped carbon matrix. • Co/Fe TMPs were fabricated by one-step low-temperature pyrolysis-phosphating approach. • The optimized TMP is a remarkable bifunctional electrocatalyst for efficient water splitting. [ABSTRACT FROM AUTHOR]

The scheme based on direct torque and flux control (DTFC) as well as active flux is a good choice for the interior permanent magnet synchronous motor (IPMSM) sensorless control. The precision of the stator flux observation is essential for this scheme. However, the performance of traditional observers like pure integrator and the low-pass filter (LPF) is severely deteriorated by disturbances, especially dc offset. Recently, a sliding-mode stator flux observer (SMFO) was proposed to reduce the dc offset in the estimated stator flux. However, it cannot eliminate the dc offset totally and will cause the chattering problem. To solve these problems, a novel super-twisting sliding-mode stator flux observer (STSMFO) is proposed in this paper. Compared with SMFO, STSMFO can reduce the chattering and fully eliminate the dc offset without any amplitude and phase compensation. Then, the precision of the stator flux and rotor position can be greatly improved over a wide speed region. The detailed mathematical analysis has been given for comparing it with another three traditional observers. The numerical simulations and experimental testing with an IPMSM drive platform have been implemented to verify the capability of the proposed sensorless scheme. [ABSTRACT FROM AUTHOR]

In this work, a novel phosphorous–nitrogen based charring agent named poly(1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (PDTBP) was synthesized and used to improve the flame retardancy of high-density polyethylene (HDPE) together with ammonium polyphosphate (APP). The results of Fourier transform infrared spectroscopy (FTIR) and 13C solid-state nuclear magnetic resonance (NMR) showed that PDTBP was successfully synthesized. Compared with the traditional intumescent flame retardant (IFR) system contained APP and pentaerythritol (PER), the novel IFR system (APP/PDTBP, weight ratio of 2:1) could significantly promote the flame retardancy, water resistance, and thermal stability of HDPE. The HDPE/APP/PDTBP composites (PE3) could achieve a UL-94 V-0 rating with LOI value of 30.8%, and had a lower migration percentage (2.2%). However, the HDPE/APP/PER composites (PE5) had the highest migration percentage (4.7%), lower LOI value of 23.9%, and could only achieve a UL-94 V-1 rating. Besides, the peak of heat release rate (PHRR), total heat release (THR), and fire hazard value of PE3 were markedly decreased compared to PE5. PE3 had higher tensile strength and flexural strength of 16.27 ± 0.42 MPa and 32.03 ± 0.59 MPa, respectively. Furthermore, the possible flame-retardant mechanism of the APP/PDTBP IFR system indicated that compact and continuous intumescent char layer would be formed during burning, thus inhibiting the degradation of substrate material and improving the thermal stability of HDPE. [ABSTRACT FROM AUTHOR]

It is recognized that cystatin C is an effective marker for monitoring the glomerular filtration rate and the clinical diagnosis of various diseases. In this study, a novel immunochromatographic method has been established to achieve quantitative detection of serum cystatin C. Unlike conventional and traditional gold immune chromatographic assays (GICAs), a uniform layer of a fluorescent film was added to the solid phase, which has been designated as the background fluorescence quenching immune chromatographic assay (bFQICA). Under the optimized conditions, there was a good correlation between the fluorescence signal ratio (F1/F2) of the background fluorescence (F1) to the fluorescence signal at the detection line (F2) for cystatin C at concentrations from 0.0 ng/mL to 100 ng/mL with a correlation coefficient of 0.9977. The detection limit was 0.69 ng/mL, and the recovery values were 87.9–105%. The differences between the intra- and interbatch precision were less than 15% in three batches. In addition, after 120 serum samples were detected, there were no significant differences in the results obtained by bFQICA and immunoturbidimetry (t = 0.963, p = 0.338 > 0.05). This work demonstrates that bFQICA is a simple, sensitive, and accurate approach for the determination of serum cystatin C, providing a new approach for the clinical diagnosis of cystatin C. [ABSTRACT FROM AUTHOR]

The conflict between rice production and water scarcity is becoming more pronounced. Therefore, the advancement of water‐saving rice cultivation is crucial in guaranteeing both food and ecological security. This study provides a summary of the development and characteristics of various water‐saving cultivation techniques for rice, including alternate wetting and drying irrigation, wet irrigation, controlled irrigation, the system of rice intensification, direct seeding rice, and dry cultivation of rice (DCR). We also introduce the varietal characteristics of upland rice, aerobic rice, water‐saving and drought‐resistant rice, and DCR. We summarize the impact of different water‐saving cultivation models on yield and quality and regulatory measures, and propose challenges and strategies for the development of water‐saving cultivation of rice in the future. We hope to provide a reference for promoting the development of rice water‐saving cultivation and dry farming agriculture. Core Ideas: This review summarizes the development of water‐saving cultivation techniques for rice.This review presents the challenges and strategies for developing water‐saving rice cultivation.This review provides technical and theoretical support for the development of rice water‐saving cultivation. [ABSTRACT FROM AUTHOR]

The phytochemical investigation on the leaves and twigs of Zanthoxylum dimorphophyllum Hemsl led to the isolation of a new compound 7-(4′ R -hydroxy-3′,7′-dimethyl-2′ E ,6′-octadienyloxy) coumarin (1) and fourteen known compounds, including nine coumarins (2 – 10), one alkaloid (11), three lignans (12 – 14) and one flavone (15). Their structures were elucidated based on extensive spectroscopic methods (NMR, MS, UV, IR and ECD experiments) and comparison with literature data. The chemotaxonomic significance of the isolated compounds has also been discussed. [Display omitted] • 15 compounds were isolated from the leaves and twigs of Zanthoxylum dimorphophyllum. • Compound 1 was a new coumarin. • Compounds 2 , 3 , 5 , 7–10 and 12 were isolated from Z. dimorphophyllum for the first time. • Chemotaxonomic relationships among Z. dimorphophyllum , the genus Zanthoxylum and the family Rutaceae were discussed. [ABSTRACT FROM AUTHOR]

Purpose: In order to find an appropriate method to synthesize a new high-efficiency flame retardant for epoxy resin. Design/methodology/approach: In this work, a flame retardant with heterocyclic groups, HOMP, was acquired after removing the obstacle from triazines which was not readily soluble. The molecular structure, thermal and flame retardant properties were fully characterized and analyzed. Also, the mechanism was researched through multi-methodologies. As well, the authors evaluated the effects of HOMP on mechanical properties. Findings: The results suggested that HOMP helped extinguish the combustion of specimens and could reach an LOI value of 29.2% and the V0 level in the UL-94 test with a phosphorus content of only 0.6wt%. With respect to the mechanism, HOMP was a gas-phase flame retardant and helped generate a thicker carbon protective coating. However, for the mechanical properties, the addition of HOMP enhanced the compressibility, while the tensile strength decreased significantly. Originality/value: The approach not only simplified the operations but also obtained HOMP with excellent flame retardant properties. [ABSTRACT FROM AUTHOR]

Co 2+ , Ni 2+ and Co 2+ /Ni 2+ co-doped β-MnO 2 were synthesized by hydrothermal reaction to study the influence of crystal defects on the microwave dielectric response. The samples were characterized by X-ray powder diffraction (XRD), X-ray fluorescence spectrometry (XRF), transmission electron microscopy (TEM), and vector network analyzer. The construction of defective β-MnO 2 , with doping of Co 2+ and Mn/O vacancies, was also discussed based on first-principles calculation. Results showed that the crystallographic defects played important role in modifying the microwave dielectric performance. The dielectric loss capacity at 2–18 GHz was enhanced after doping of Ni 2+ and Co 2+ , which was ascribed to the ionic polarization process. In the deficient configurations, the appearance of Mn vacancy narrowed the band gap, forming weak bound electrons and weak contact ions. Then the electronic and ionic relaxation polarization processes took place among these charged particles in the applied field. Mn vacancy was the most important factor in controlling the microwave polarization process, followed by O vacancy and extrinsic Co 2+ . [ABSTRACT FROM AUTHOR]

The theoretical calculation of polyaniline tetramers were performed in implicit water solvent medium using the polarizable continuum model with density functional theory. In order to explore the protonation mechanism of polyaniline, the geometry characteristics, charge distribution, frontier molecular orbitals (MOs) and stability of emeraldine base and emeraldine salts in tetramer were investigated by B3LYP/6-31G+(d,p), and the significant increase mechanism of the electrical conductivity of polyaniline upon protonation was researched in detail. It was shown that optimized molecular geometry by protonation doping suggested a tendency towards bipolaron delocalization and a greater π-conjugation proved by bond length alternation and the torsional angles. Furthermore, the NBO of ES3 was distributed equably and should be conducive to the electrical conductivity, the frontier MOs were effectively established, and an electronic transition from HOMO to LUMO+1 is turned out to be a ππ* transition finally. In addition, compared with the computed energies of different emeraldine salt configurations, the bipolaronic lattice was taken for the most stable structure. [ABSTRACT FROM AUTHOR]

Geological studies show that the southern part of Ailaoshan-Red River shear zone (ALSRRSZ) has experienced complex metallogenic processes and multi-stage non-uniform uplifting, called oblique uplifting since the Cenozoic. To detect the deep structure and geodynamic background beneath Daping, Chang'an and other gold and polymetallic deposits in this area, we carried out a high-density short-period seismic array survey in southern Yunnan province. The array used is approximately 240 km long with an interval of 500 m between two adjacent stations. Based on the data collected by the array, we used H-κ stacking and common conversion point (CCP) methods of receiver functions to reveal the fine crustal structure beneath this array, which was located from Lvchun (western end) to the east and ended in Maguan. The three main conclusions are as follows. (1) The average crustal thickness is approximately 37 km and the Vp/Vs ratio is 1.75. However, the thickness and Vp/Vs ratio of the Ailao Mountain are rather greater or higher than those of the western Lanping-Simao Basin and eastern South-China block. These results may indicate that the crust is rich in ferromagnesian minerals or has a thermal fluid anomaly after orogenic movement. (2) There are two obvious inclined interfaces beneath the Ailao Mountain in the mid-upper crust, which suggests that strong deformation occurred there during the orogenic period. Some evidences, such as the weak converted-wave Pms phase from the Moho, low P-wave velocities of the upper mantle, high surface heat flow values, and generally developed hot springs, indicate that a strong crust-mantle interaction exists in the southern segments of the Ailaoshan-Red River shear zone. These interactions include a diapir of mantle-sourced magma (stronger in the east than that in the west), lateral collision from the Indian Plate, and the differential uplift caused by the strike-slip movement of the Red River Fault. All of above deep processes led to the Cenozoic oblique uplifting of Ailao Mountain. (3) By combining the location of the deposits on the surface, characteristics of the average crustal Vp/Vs ratio, hypocenters of the small earthquakes along the research profile, Moho shape, and horizontal variations of the Pms phase amplitudes, we speculate that the Ailaoshan Fault was the upgoing conduit for metallogenic magma and played a significant role in the Cenozoic development of the multiform metal deposits around the Ailao Mountain area. [ABSTRACT FROM AUTHOR]

The phytochemical investigation on the whole plant of Lysionotus pauciflorus led to the isolation of a new flavonoid (1), along with eight known flavonoids (2 – 9), as well as five alkaloids (10 – 14). Their structures were elucidated based on extensive spectroscopic methods (1D and 2D NMR, HRESIMS, IR, and UV experiments), coupled with comparison with literature data. Among these known compounds, compounds 2 , 4 – 6 , 10 – 14 were isolated from L. pauciflorus for the first time. What is particularly exciting is that alkaloid compounds, which possessed indole skeleton, were found in Gesneriaceae plants for the first time. The chemotaxonomic significance of these isolated compounds has also been discussed. The highly oxygenated flavones identified in the plant may be used as chemotaxonomic marker of Lysionotus. [Display omitted] • 14 compounds were isolated from the whole plant of Lysionotus pauciflorus. • Compound 1 was a new flavonoid. • Compounds 2 , 4 – 6 , 10 – 14 were isolated from L. pauciflorus for the first time. • The alkaloids were found in Gesneriaceae plants for the first time. • Highly oxygenated flavones can be recognized as typical biomarkers for the genus Lysionotus. [ABSTRACT FROM AUTHOR]

β-MnO 2 microncube is a novel morphology of microncube with rectangular pyramid. It has been synthesized for the first time via a simple aqueous chemical route under hydrothermal conditions without any templates. When the reaction time is increased from 1 h to 10 h, the crystal type changed from γ-MnO 2 to β-MnO 2 and the morphology changed from an urchin-like shape to a microncube with rectangular pyramid. We propose a possible growth mechanism for intrinsic structural growth mechanism, the evolution process of the β-MnO 2 structure is proposed to involve two main stages. Besides, the electromagnetic properties of the synthesized β-MnO 2 were investigated. It shows that β-MnO 2 has certain dielectric loss properties and an effective absorption bandwidth (reflection loss lower than − 10 dB) of 3.5 GHz was achieved from the β-MnO 2 /paraffin wax composite. [ABSTRACT FROM AUTHOR]

Mn doped with various loadings of nitrogen was prepared by nitridation of a micron α-Mn powder in a flowing ammonia atmosphere at a range of temperatures from 400 to 900 °C. X-ray diffraction (XRD) studies reveal that doping nitrogen content increases as the temperature rising from 400 to 600 °C and then decreases from 600 to 900 °C. A mass of ε-MnN started to form during the heat treatment of α-Mn powder at 900 °C. The structural morphology and grain size of the products were carried out using scanning electron microscope (SEM). Vibration sample magnetometer (VSM) and vector network analyzer (VNA) were employed to investigate the effect of nitrogen doping on the magnetic and electromagnetic performance of the as-synthesized samples. Odd circles were found in the $\varepsilon ^{\prime } - \varepsilon ^{\prime \prime }$ figure, which may come from the interaction between electron charge and applied field. In addition, sphere Landau-Lifshitz-Gilbert (LLG) equation fitting approach is adopted to explain the magnetic resonance of the 900 °C sample. The composite of the 900 °C sample exhibits a wider frequency range for microwave absorption applications than other composites. The sample with a thickness of 7 mm shows two absorption peaks at about 3.6 and 14.48 GHz with the maximum reflection loss of −28.71 dB at 11.18 GHz and the absorption range below −5 dB from 2 to 18 GHz. [ABSTRACT FROM AUTHOR]

Hypericum monogynum L. (Hypericaceae) has been used as a folk Chinese medicine for the treatment of inflammatory related diseases. Cyclooxygenase-2 (COX-2) is a crucial target for the development of agents to treat inflammation. To search for anti-inflammatory compounds from traditional Chinese medicines, a chemical constituent study along with COX-2 inhibitory activity analysis was performed for this plant. In this study, sixteen chemical monomers, including three undescribed oxidative degradation polycyclic polyprenylated acylphloroglucinols (PPAPs, hypemoins C–E), two undescribed PPAPs (hypemoins A and B), and 11 known compounds, were identified from the flowers of H. monogynum. Their structures were characterized by HRESIMS, NMR techniques, ECD, and single crystal X-ray diffraction. Four flavonoid derivatives showed remarkable COX-2 inhibitory activities, with IC 50 values ranging from 0.220 ± 0.006 to 1.655 ± 0.098 μM. Among these compounds, the possible recognition mechanism between quercetin 3-(6″-O-caffeoyl)-β-3-D-galactoside and COX-2 was predicted by molecular docking analysis. Moreover, the multidrug resistance reversal activities for the selected compounds were evaluated. Sixteen chemical monomers, including three undescribed oxidative degradation polycyclic polyprenylated acylphloroglucinols (PPAPs, hypemoins C–E), two undescribed PPAPs (hypemoins A and B), and 11 phenol derivatives were discovered from the flowers of Hypericum monogynum. Four flavonoids showed remarkably COX-2 inhibitory activities with IC 50 values ranging from 0.220 ± 0.006 to 1.655 ± 0.098 μM. [Display omitted] • Five undescribed compounds were isolated from Hypericum monogynum. • Four flavonoids showed remarkably COX-2 inhibitory activities. • The possible recognition mechanism was predicted by molecular docking. • The multidrug resistance reversal activity was also evaluated. [ABSTRACT FROM AUTHOR]

Two electroactive polyoxometalates (POMs)-based metal-organic frameworks (MOFs) films (POMOFs) in situ grown on carbon cloth (NENU-3/CC and NENU-5/CC) were synthesized by a facile one-step solvothermal method containing Cu(NO 3) 2 , 1,3,5-benzentricarboxylate (H 3 BTC) and POMs (PMo 12 and PW 12), in which the POMs were wrapped into MOFs to increase stability. The analysis of electrochemical behavior of the NENU-3/CC and NENU-5/CC films reveals that they can serve as conductive electrode materials. Subsequently, two kinds of film electrodes exhibit enhanced electrocatalytic activity toward bromate reduction in acidic solution. Thus, they can act as electrochemical sensors to detect bromate. Amperometric detection results of NENU-3/CC to bromate show a high sensitivity of 45.11 μA cm −2 mM−1 and a low detection limit of 0.55 μM. Furthermore, NENU-5/CC can exhibit a detection limit of 1.18 μM, and a high sensitivity of 18.83 μA cm−2 mM−1. Experimental results show that two POMOFs films have high electrochemical stability as working electrode materials and good selectivity for detecting bromate as sensor materials. Up to now, electrochemical methods to detect bromated have attracted considerable attention due to their simplicity, rapidity, high sensitivity, excellent selectivity and environmentally friendliness with low-cost equipment compared with other techniques. Polyoxometalates (POMs) have been widely used for the electrocatalytic reduction of bromate because of their high redox properties. However, when POMs are used as conductive electrodes materials, they dissolve easily in the electrolyte, and the instability of POMs can increase performance degradation. For solving the above-mentioned problem, POMs are encapsulated into MOFs to generate POM-based MOFs (POMOFs), it combine the merits of POMs and MOFs and increase the stability of skeleton. However, POMOFs materials can increase the reversible electrochemical capacity, the leaching and dispersity of POMOFs in the electrocatalytic measurement can make them unstable, and it hinders the conductivity in electrochemical behaviors. Thus, Proper POMOFs films have been developed to overcome the aforementioned difficulties by packing POMOFs on the conductive substrates uniformly to increase the stability and performance in electrochemical catalysis. In this paper, two electroactive polyoxometalates (POMs)-based metal-organic frameworks (MOFs) films (NENU-3 and NENU-5) were chosen as target materials in the synthesis of POMOFs film. And they were located on the surface of the carbon cloth through a facile in situ one-step solvothermal method as conductive electrode materials. According to report, NENU-3 and NENU-5 were coated on the substrate using hot-pressing and electrochemical method, we firstly prepared NENU-3/CC and NENU-5/CC films by in situ one-step solvothermal method, and the as-synthesized POMOFs materials using this method are more uniform, facile, and stable than other methods. The results of amperometric detection of NENU-3/CC to bromate show a wide linear range of 5–560 μM with a high sensitivity of 45.11 μA cm−2 mM−1 and a low detection limit of 0.55 μM. Furthermore, NENU-5/CC can exhibit a good linearity range of 15–380 μM, a detection limit of 1.18 μM, and a high sensitivity of 18.83 μA cm−2 mM−1. As a result, the amperometric determination demonstrates that two as-synthesized POMOFs/CC films as working electrode materials exhibit good sensitivity, selectivity, and stability to detect bromate as sensor materials. Two electroactive polyoxometalates (POMs)-based metal-organic frameworks (MOFs) films (POMOFs) in situ grown on carbon cloth (NENU-3/CC and NENU-5/CC) were prepared by a facile one-step solvothermal method. The analysis of electrochemical behavior of the POMOFs films reveals that they can serve as conductive electrode materials toward bromate reduction in acidic solution. Experimental results show that two POMOFs films have high electrochemical stability as working electrode materials and good selectivity for detecting bromate as sensor materials. Unlabelled Image • Two POMOFs were in situ grown on carbon cloth as electrode films. • The prepared electrodes were used as chemical sensor to detect bromate. • Electrochemical sensors were fabricated by a facile one-step solvothermal method. • The proposed sensors show high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]