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Clustering is an essential unsupervised technique when category information is not available. Although K-means and Max-min distance K-means clustering algorithms are widely used, they have some disadvantages such as dependence on the initial centers, sensitivity to outliers caused by using only distance as the clustering criterion. To overcome the problems, this paper proposes SMM-K-means algorithm which overcomes the dependence on the initial cluster centers and the initial number of clusters and the sensitivity to the outliers. First, the initial value K of the optimal cluster number is determined by the elbow method, and K-means is used for initial clustering. A new inter-cluster separation measure is then constructed based on the idea of q-nearest neighbors, which is constructed by comprehensive considering the separation between clusters and the distribution compactness of clusters themselves. Finally, the two sample points with highest degree of separation are brought into Max-min distance K-means algorithm as new initial centers for clustering. The definite determining method of cluster centers eliminates the complicated iterative calculation, and the construction of inter-cluster separation measure overcomes the sensitivity of clustering results to noise points and isolated points, and has good applicability and generalization. In addition, this algorithm is not limited by the shape and size of the clusters and has better flexibility. The experimental results show that the SMM-K-means algorithm has higher CH values, resulting in a better clustering effect and stability. [ABSTRACT FROM AUTHOR]

The thermoelectric properties of Bi 0.5 Sb 1.5 Te 3 synthesized through the low-temperature liquid phase sintering (LPS) method can be significantly improved by employing a synergistic approach. During the heat treatment, excess Te undergoes self-swelling under optimal sintering pressure, facilitating the slip of matrix grains perpendicular to the applied pressure and subsequent recrystallization, leading to enhanced electrical properties. Building upon this basis, the heightened Seebeck coefficient and power factor of the thermoelectric matrix stem from the incorporation of 0.6 vol% B 4 C nanoparticles. Simultaneously, lattice thermal conductivity experiences notable suppression due to enhanced phonon scattering induced by additional interfaces, defects, and second-phase. Lastly, a markedly improved maximum ZT value of 1.30 at 333 K is achieved when the volume percentage of B 4 C nanoparticles is 0.6 vol%, representing a remarkable 23% enhancement compared to the untreated sample. These results indicate that the LPS method, coupled with the enhanced second nanophase scattering mechanism, is beneficial to enhancing the thermoelectric properties of Bi 2 Te 3 -based materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Thermoelectric devices that consist of N-and P-type TE legs in series have been well known and applied owing to the ability that could convert waste heat into electric energy. Among them, skutterudite materials have been frequently studied as the main object because they are environmentally friendly and inexpensive. In this study, N-type CoSb 3 -based materials were synthesized using a low-temperature synthesis method and spark plasma sintering. Those thermoelectric matrix that incorporated Indium (In) particles were prepared via manual grinding method. The thermoelectric properties, microstructures, and morphologies of the pure and In-doped Co 0.91 Ni 0.09 Sb 3 samples were systematically evaluated. A maximum power factor value of 3642.3 μW/mK2 was obtained at 723 K for a Co 0.91 Ni 0.09 Sb 3 /1 wt%In sample and the highest figure of merit value of 1.01 was attained for a Co 0.91 Ni 0.09 Sb 3 /2 wt%In sample. These results indicate that Indium particles as secondary phase can improve the thermoelectric performance of N-type CoSb 3 -based materials. [ABSTRACT FROM AUTHOR]

High-performance one-dimensional (1D) CdSxSe1−x nanostructures arrayed photodetectors exhibit broad spectrum (450–750 nm) selective detection from the near-ultraviolet to the near-infrared regime, which has a great deal of interest in broad spectral flexible optoelectronic devices. Here, we report the microstamp transfer technology to construct high-performance rigid (SiO2/Si) and flexible (polyethylene terephthalate) photodetectors with broad spectrum selective detection, which was based on arrayed 1D CdSxSe1−x nanostructures obtained via chemical vapor deposition in a dual-temperature zone tube furnace. Photoresponse measurements have demonstrated their superior spectral photoresponsivity (∼105 AW−1), extremely high on/off switching ratio (105), rapid response/recovery time between 10% and 90% of the maximum photocurrent (0.089/0.044, 0.044/0.044, 0.133/0.131, and 0.178/0.180 s), and excellent long-term environmental photostability. Furthermore, the as-prepared flexible arrayed photodetector displayed excellent folding endurance properties (after 2000 times, the photocurrent decreases less than 50%) and stable electrical properties (bending angle from 0° to 150°). The improvement nanoarray technology in this research can be exploited to lead to the design of high-performance flexible photodevices comprising other 1D or 2D alloy nanomaterials. [ABSTRACT FROM AUTHOR]

In this paper, we first proposed a statistical test for the detrended multiple moving average cross-correlation coefficient DMMC (s). The DMMC (s) mainly was used to analyze the correlation between the dependent variable y and other n independent variables x i . We proved that DMMC (s) approximately obeys the chi-square distribution. We studied the statistical properties of the DMMC (s) between normally distributed random sequences and power-law ARFIMA long memory random sequences. Furthermore, we discussed the influence of the cross-correlation among the target variable and independent variables on DMMC (s). Finally, we further study the application of DMMC (s) to China's stock markets and China carbon emission trading markets to investigate multiple cross-correlation. The empirical results show that there is a strong multiple correlation between China's Shanghai, Shenzhen and Hong Kong stock markets, while the correlation between China's carbon markets is not significant. This paper provides new ideas and theoretical support for exploring the correlation between multiple variables, which has implications for investors and policymakers. [ABSTRACT FROM AUTHOR]

Abuse of antibiotics in animal husbandry and medicine has led to severe environmental problems especially the risk of bacterial resistance. Different from common organic pollutants, antibiotics in wastewater could not be easily removed by biological treatment because of their poor biodegradability. Electrocatalysis including electrocatalytic oxidation and reduction has gained great attention for the removal of antibiotic contaminants in wastewater due to its advantages of high efficiency, simple operation, and thorough degradation. This review summarizes the common features and synthesis methods as well as research progress of electrode materials used in the electrocatalytic process for the treatment of antibiotics in the last five years. The removal mechanism and transformation pathways of antibiotics in the electrocatalytic oxidation and reduction processes are presented, especially to avoid the second pollution. Cost aspects in the electrocatalytic process are also discussed by considering practical applications and comparison with adsorption and photocatalysis process. Finally, several developing directions of electrocatalysis in the antibiotic wastewater treatment are proposed as a guidance for further research. [ABSTRACT FROM AUTHOR]

In the face of the batch, dynamic access data, or the flow of data that continuous changes over time, the traditional support vector machine algorithm cannot dynamically adjust the previous classification model. To overcome this shortcoming, the incremental support vector machine (ISVM) algorithm is proposed. However, many incremental support vector algorithms still have shortcomings such as low efficiency, memory limitation, and poor generalization. This paper puts forward the new ISVM algorithm, HDFC-ISVM ∗ algorithm, based on the high-dimensional distance and forgetting characteristics. This paper firstly proposes the original HDFC-ISVM algorithm that first learns the distribution characteristics of the samples according to the distance between the samples and the normative hyperplane. Then, it introduces the forgetting factor. In the incremental learning process, the classifier gradually accumulates the spatial distribution knowledge of samples, eliminates the samples that have no contributions to the classifier, and selectively forgets some useless samples according to the forgetting factor, which overcomes the shortcomings such as low efficiency and poor accuracy of some algorithms. But, the original HDFC-ISVM algorithm is sensitive to parameters, and different settings of the parameters have a great impact on the final classification accuracy of the algorithm. Therefore, on the basis of the original algorithm, an improved algorithm HDFC-ISVM ∗ based on the adjustments to the initialization strategy and updating rules of the forgetting factor is proposed. The initialization strategy and updating rules of the forgetting factor are adjusted to adapt datasets with different distributions in this improved algorithm. The rationality of the improved strategy about the forgetting factor is discussed theoretically. At the same time, the proposed algorithm has better classification accuracy, classification efficiency, and better generalization ability than other algorithms, which is verified by experiments. [ABSTRACT FROM AUTHOR]

Ladder resonant switched-capacitor converters (RSCCs) provide high step-up voltage gain, but the continuous regulation range is typically limited with an extremely wide switching frequency band. This article introduces a new full-range regulation method for step-up ladder RSCCs along with seven switching techniques. Each switching technique offers multiple possibilities for implementation. Furthermore, ladder RSCCs with the proposed switching techniques feature the merits of simple control, soft switching, and high efficiency. A comprehensive analysis of operation principle, voltage gain curves, device stress, active switch utilization, zero voltage switching range, output voltage ripple, and input current ripple is given for the proposed seven switching techniques. A 3X step-up Ladder RSCC prototype was built and tested to validate the theoretical results. [ABSTRACT FROM AUTHOR]

Adsorption desalination and cooling is a promising technology that has recently been investigated. In this study, a silica gel powder composite (SGPC) with nano-copper (NC) and polyvinyl pyrrolidone (PVP) was synthesized by mechanical grinding and melt blending for the first time. It can improve the thermal conductivity of silica gel powder (SGP) and the operation efficiency of the adsorption desalination and cooling system (ADCS). By measuring the curve of temperature variation to compare the four thermal conductivity enhancers (TCE), graphite powder (GP), carbon nanotubes (CNT), nano-alumina (NA) and NC, it was found that NC had the best thermal conductivity enhancement. The microstructure, adsorption and thermal properties of the SGPC samples were systematically characterized by scanning electron microscopy (SEM), thermogravimetric analyzer (TGA) and thermal constant analyzer. The results showed that the adsorption capacity of SGPC with NC content of 0–1.6 wt% was in the range of 0.29–0.33 g −1. The thermal conductivity of SGPC with NC content of 0.8wt%, 1.2 wt%, and 1.6 wt% was found to be improved by 114%, 156% and 185% compared to the parent SGP, and the thermal conductivity was effectively enhanced. Thus, the developed adsorbent has eximious water adsorbability and thermal conductivity and has good adsorption/desorption cycle stability, which is attractive for ADCS. [ABSTRACT FROM AUTHOR]

Evaluating the accuracy of the satellite and reanalysis precipitation products is very important for understanding their uncertainties and potential applications. However, because of underestimation existing in commonly used evaluation benchmark, gauge precipitation data, it is necessary to investigate the influence of systematic errors in gauge data on the performance evaluation of satellite and reanalysis precipitation datasets. Daily satellite-based IMERG and model-based ERA5-Land, together with gauge precipitation data, were collected with the period from 2005 to 2016 over China in this study. Daily corrections for precipitation biases from wind-induced undercatch, wetting loss, and trace error were made for gauge measurements. A set of metrics, including relative bias, Kling-Gupta efficiency, frequency bias, and critical success index, were used to evaluate and intercompare the performances of IMERG and ERA5-Land against original and bias-corrected gauge data in different locations, years, seasons, climatic zones, classes of precipitation events, and precipitation phases. The results have shown that: After removing the bias in gauge data, the relative biases of IMERG and ERA5-Land both significantly decline. The noticeable changes of their accuracy occur and vary with different locations, years, seasons, climatic zones, and precipitation phases. Furthermore, the frequency biases of IMERG and ERA5-Land rise in no precipitation events and decline in light, moderate, heavy, and extreme precipitation events. The detection capability of IMERG and ERA5-Land in no and light precipitation events is also obviously affected. Therefore, this study has demonstrated the significant influence of systematic gauge precipitation errors on the assessment of IMERG and ERA5-Land and reinforces the necessity to remove negative bias in gauge data before using it as the benchmark. [ABSTRACT FROM AUTHOR]

Clarifying the microscale reaction mechanism of macerals is crucial for achieving efficient thermal utilization of coals. Herein, we analysed the chemical structures of two coals used in coking for their macerals employing 13C NMR, FTIR, and XPS to build molecules. The pyrolysis behaviours of coals and their macerals were accessed through molecular dynamics of calculating chemical bond characteristics. Results show that inertinite with higher maturity is rich in aromatic, vitrinite with stronger thermal-reactivity is rich in aliphatic, and macerals of coking and gas coal have more advantages in hydrocarbon generation and branch-chain development, respectively. Based on the validated and optimized molecules containing C, H, O, and N elements, it is found that not only the bond lengths of the longest and shortest in macerals from gas coal are greater than those from coking coal, but the thermal response of heteroatom bonds in the former is almost twice that of the later. Moreover, vitrinite and inertinite of coking coal have N–H cleavage to produce active hydrogen in the late stage of bond dissociation, while gas coal lacks this feature. These explain why the pyrolytic properties of different coals and their macerals have variability, guiding the rational selection of coal-based feedstock for industry. [Display omitted] • Molecular differences between vitrinite and inertinite of various coals are elucidated by characterizations and simulations. • Complex carbon-based molecules are constructed by a strategy that prioritizes the structure of trace heteroatoms. • Differences in thermal conversion of coals are revealed by changes in bond lengths of maceral molecules. [ABSTRACT FROM AUTHOR]

Herein, the magnetic field facilitated electrocatalytic degradation of tetracycline is reported for the first time. A magnetic porous carbonized phthalonitrile resin electrocatalyst has been prepared through directly annealing phthalonitrile monomer, polyaniline coated barium ferrite and potassium hydroxide. The tetracycline degradation percentage (DP%) by such electrocatalyst is significantly increased up to 37.42% under magnetic field with the optimal pH value of 5.0 and bias voltage of 1.0 V (vs. SCE). The mechanism of this phenomenon is explained by the spin-selective electron removal process in the reaction between metal-oxygen species and tetracycline on the electrocatalyst. The comparison of degradation pathways for tetracycline with and without magnetic field confirms the improvement of tetracycline DP%. This work opens a new direction for the application of an external magnetic field in the electrocatalytic degradation of antibiotics in wastewater. [Display omitted] • A novel magnetic porous carbonized phthalonitrile resin was successfully prepared. • Magnetic field enhanced electrocatalytic degradation of tetracycline was observed. • Spin-selective electron removal process was proposed in tetracycline degradation. • Degradation pathways with/without magnetic field affirmed the boost of degradation. [ABSTRACT FROM AUTHOR]

Multilevel resonant switched-capacitor converters (RSCCs) have drawn attention in large step-down voltage conversion but are hindered in a wide area of applications due to limited voltage regulation range. A new full-range regulation (FR) method for multilevel step-down RSCCs is proposed in this article. As an example of the proposed FR method, the fixed on-time modulation for modified Dickson RSCC is provided. In addition to full-range voltage regulation, the multilevel RSCCs with the proposed FR method feature complimentary driving signals, zero voltage switching turn-on for switches, zero current switching turn-off for diodes, even switch voltage stress, even diode voltage stress, high active switch utilization, high efficiency, and high power density. A modified Dickson RSCC prototype was built to validate the proposed FR method. The proposed FR method is further extended to series-parallel RSCCs and Fibonacci RSCCs. [ABSTRACT FROM AUTHOR]

Support vector machines (SVMs) are designed to solve the binary classification problems at the beginning, but in the real world, there are a lot of multiclassification cases. The multiclassification methods based on SVM are mainly divided into the direct methods and the indirect methods, in which the indirect methods, which consist of multiple binary classifiers integrated in accordance with certain rules to form the multiclassification model, are the most commonly used multiclassification methods at present. In this paper, an improved multiclassification algorithm based on the balanced binary decision tree is proposed, which is called the IBDT-SVM algorithm. In this algorithm, it considers not only the influence of "between-classes distance" and "class variance" in traditional measures of between-classes separability but also takes "between-classes variance" into consideration and proposes a new improved "between-classes separability measure." Based on the new "between-classes separability measure," it finds out the two classes with the largest between-classes separability measure and uses them as the positive and negative samples to train and learn the classifier. After that, according to the principle of the class-grouping-by-majority, the remaining classes are close to these two classes and merged into the positive samples and the negative samples to train SVM classifier again. For the samples with uneven distribution or sparse distribution, this method can avoid the error caused by the shortest canter distance classification method and overcome the "error accumulation" problem existing in traditional binary decision tree to the greatest extent so as to obtain a better classifier. According to the above algorithm, each layer node of the decision tree is traversed until the output classification result is a single-class label. The experimental results show that the IBDT-SVM algorithm proposed in this paper can achieve better classification accuracy and effectiveness for multiple classification problems. [ABSTRACT FROM AUTHOR]

In this article, a step-down switched-capacitor converter (SCC) and a step-up SCC with an integrated passive regenerative snubber (PRS) are proposed based on the Cuk dual resonance core (DRC). The members of the DRC converter family overcome the barrier for SCCs to achieve continuous output voltage regulation. One remaining challenge is the turn-off spikes and oscillations during the switch turn-off transient that cause voltage stress and power loss to the transistor and diode. The proposed integrated PRS eliminates voltage spikes and oscillations across the transistor and diode during the turn-off process. Moreover, zero voltage switching (ZVS) turn-on for the clamped mosfet, zero current switching (ZCS) turn-on for the other mosfet and ZCS turn-off for all diodes are achieved. A comprehensive analysis of the operation principle, conversion ratio curves, component stress, and regenerative power of the proposed converters with regenerative snubbers is given. Furthermore, a performance comparison between the proposed snubber configuration and two conventional methods is given. A 50 V/99.25 V step-up converter prototype of 125 W has demonstrated a peak efficiency of 98.4%. The analysis is verified by both simulation and experiments. [ABSTRACT FROM AUTHOR]

In this paper, a family of new step-up series–parallel dual resonant switched-capacitor converters (SP-DRSCs) is proposed to extend the conversion ratio for high step-up applications. The converters feature a wide gain range, continuously adjustable, and enhanced light-load voltage regulation. All flying capacitors operate in resonance, eliminating high transient current spikes and charge sharing losses. Thus, zero-current-switching (ZCS) turn-on for all transistors and ZCS turn-off for all diodes are achieved. A comprehensive analysis of the operation principle, voltage-gain curves, stable regulation range, and voltage and current stress is given. An analytical method to quantify the passive component volume for the group of step-up dual resonance switched-capacitor converters is presented. Further design considerations to optimize the passive component volume of the proposed SP-DRSC and the effect of bulky bypass capacitors on the volume are discussed. [ABSTRACT FROM AUTHOR]

A diffusive SIS epidemic model with Holling II incidence rate is studied in this paper. We introduce the basic reproduction number ℛ 0 first. Then the existence of endemic equilibrium (EE) can be determined by the sizes of ℛ 0 as well as the diffusion rates of susceptible and infected individuals. We also investigate the effect of diffusion rates on asymptotic profile of EE. Our results conclude that the infected population will die out if the diffusion rate of susceptible individuals is small and the total population N is below a certain level; while the two populations persist eventually if at least one of the diffusion rates of the susceptible and infected individuals is large. [ABSTRACT FROM AUTHOR]

This paper proposes a new interleaved high step-up converter with coupled inductors. Interleaving configuration is employed at the input side to reduce the input current ripple and increase the power level. The series structure at the output side helps achieve a very high step-up voltage gain. Also, the proposed converter has very low switch voltage stress; thus, switching loss can be reduced and low-voltage-rating mosfets with small on resistance are allowed to lower the conduction loss. Due to the passive clamp performance, the leakage energy of the coupled inductors can be recycled and large voltage spikes across the switches are alleviated. Furthermore, with the aid of the leakage inductances, zero-current switching of the active switches can be achieved and the reverse recovery problem of the diodes is alleviated. The operating principles, performance analysis, and design considerations of the proposed converter are discussed. A prototype with 20-V input and 400-V output is built, and experimental results are provided to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

The imbalance data refers to at least one of its classes which is usually outnumbered by the other classes. The imbalanced data sets exist widely in the real world, and the classification for them has become one of the hottest issues in the field of data mining. At present, the classification solutions for imbalanced data sets are mainly based on the algorithm-level and the data-level. On the data-level, both oversampling strategies and undersampling strategies are used to realize the data balance via data reconstruction. SMOTE and Random-SMOTE are two classic oversampling algorithms, but they still possess the drawbacks such as blind interpolation and fuzzy class boundaries. In this paper, an improved oversampling algorithm based on the samples' selection strategy for the imbalanced data classification is proposed. On the basis of the Random-SMOTE algorithm, the support vectors (SV) are extracted and are treated as the parent samples to synthesize the new examples for the minority class in order to realize the balance of the data. Lastly, the imbalanced data sets are classified with the SVM classification algorithm. F-measure value, G-mean value, ROC curve, and AUC value are selected as the performance evaluation indexes. Experimental results show that this improved algorithm demonstrates a good classification performance for the imbalanced data sets. [ABSTRACT FROM AUTHOR]

In this paper, a family of automatic interleaved Dickson switched-capacitor converters (AIDSCC) and its zero-voltage switching (ZVS) resonant configuration are proposed. Different from the traditional Dickson switched-capacitor converter, the AIDSCC has symmetrical configuration with the features of automatic interleaved input current, small output voltage ripple, and lower peak capacitor voltage stress. To improve the line regulation capability, one small resonant inductor is inserted and two bulky capacitor banks are replaced by two much smaller resonant capacitors, forming the resonant AIDSCC. The transistors are ZVS turned on and diodes are zero-current switching turned off by operating above the resonance. With frequency modulation within a reasonable range, the voltage-gain range of the resonant AIDSCC is expanded significantly, while sacrificing the maximum efficiency due to the higher conduction loss. A 3X AIDSCC and a 3X resonant AIDSCC below 140 W were built to verify the analysis. [ABSTRACT FROM AUTHOR]

Thermodynamic and kinetic parameters of co-combustion of textile dyeing sludge (TDS) and sugarcane bagasse (SB) were studied using thermogravimetric analysis in CO 2 /O 2 and N 2 /O 2 atmospheres. Our results showed that the comprehensive combustion characteristic index ( CCI ) of the blends was improved by 1.71–4.32 times. With the increased O 2 concentration, co-combustion peak temperature decreased from 329.7 to 318.2 °C, with an increase in its maximum weight loss rate from 10.04 to 14.99%/min and its CCI by 1.31 times ( β  = 20 °C·min −1 ). To evaluate the co-combustion characteristics, thermodynamic and kinetic parameters (entropy , Gibbs free energy and enthalpy changes, and apparent activation energy) were obtained in the five atmospheres. The lowest apparent activation energy of the TB64 blend was obtained in oxy-fuel atmosphere (CO 2 /O 2  = 7/3). [ABSTRACT FROM AUTHOR]

This study aimed at the quantification of thermochemical behaviors of textile dye sludge (TDS), paper mill sludge (PMS), and their various blend ratios during (co-)combustion. Changes in mass loss percentage (MLP) and rate (MLR) were estimated as a function of temperature, heating rate, and blend ratio. Our results pointed to a direct influence of blend ratios on mass loss percentage. Stochastic uncertainties and sensitivities associated with best-fit predictions of MLP and MLR responses were detected using all-at-once versus one-at-a-time Monte Carlo simulations. Co-combustion of TDS and PMS provided more flame stability owing to their volatile matter contents than did the combustion of pure TDS or PMS. The high C and H contents of TDS relative to those of PMS led to high lower heating value (higher energy). Effect of increased temperature on the co-combustion manifested itself in the breakdown of (hemi-)cellulose initially and lignin progressively in TDS and PMS. The increasing TDS of the blend ratio increased both MLP and MLR. Stochastic uncertainty analysis of the deterministic empirical models pinpointed overestimation by 15.6% in mean MLP and by 50% in mean MLR. Sensitivity analysis pointed to blend ratio as the most influential predictor on both MLP and MLR. [ABSTRACT FROM AUTHOR]

The polymer nanocomposites with 3-dimensional (3D) nanofillers can form a 3D network and attain a uniform distribution of nanofillers, which benefits the transfer of charge carriers and phonons as well as the dispersion of stress at a very low loading of nanofillers. These polymer nanocomposites with high mechanical properties would have great potential for thermal and electrical conduction as well as electromagnetic interference (EMI) shielding. In this paper, the 3D epoxy nanocomposites are manufactured by stuffing epoxy resin into 3D p -phenylenediamine-aniline copolymer nanofibers@Cu foam (P-PANI@f-Cu) hybrid nanofillers that are constructed by electrophoretic deposition of phosphoric acid doped P-PANI copolymer nanofibers onto the surface of sodium hydroxide oxidized Cu foam. Benefiting from 3D continuous network of P-PANI@f-Cu hybrid nanofillers, the electrical conductivity and thermal conductivity of 3D P-PANI@f-Cu/epoxy nanocomposites with the P-PANI loading of 0.262 wt% could achieve 7.71 ± 0.04 S cm−1 and 5.4670 ± 0.0085 W m−1K−1, respectively, which are much better than that of pure epoxy (insulator and 0.2310 ± 0.0017 W m−1K−1, respectively) and epoxy composites filled with only Cu foam (4.46 ± 0.03 S cm−1 and 2.7907 ± 0.0057 W m−1K−1, respectively). Meanwhile, with a thickness of 1.8 mm, the average total EMI shielding effectiveness (SE T) of 3D P-PANI@f-Cu/epoxy nanocomposites in the X-band range reaches a high value of 66.14 dB, which is capable of effectively shielding the electromagnetic signal between Bluetooth earphone and smartphone in the practical application. Furthermore, the 3D P-PANI@f-Cu hybrid nanofillers can efficiently prevent the crack growth in the epoxy nanocomposites and improve their mechanical properties including hardness and elastic modulus. The 3D p -phenylenediamine-aniline copolymer nanofibers @Cu foam/epoxy nanocomposites possess the outstanding thermal conductivity, electrical conductivity, mechanical properties and electromagnetic shielding properties arising from the continuous porous network of 3D hybrid nanofillers and the synergistic interaction among 3D Cu skeleton, P-PANI nanofibers, and epoxy matrix, which can effectively shield the signal between Bluetooth earphone and smartphone in practical application. [Display omitted] • 3D p -phenylenediamine/aniline@Cu foam/epoxy nanocomposites are fabricated. • 3D P-PANI@f-Cu/epoxy nanocomposites exhibit outstanding EMI shielding performance. • P-PANI@f-Cu/epoxy could shield EM signal between Bluetooth earphone and smartphone. • 3D P-PANI@f-Cu/epoxy has excellent thermal conductivity and mechanical properties. [ABSTRACT FROM AUTHOR]

Based on the traditional detrended moving average cross-correlation analysis (DMCA) method and the detrended multiple cross-correlation analysis (DMC) method, we propose the detrended multiple moving average cross-correlation analysis method (DMMC) to quantify the correlation between non-stationary signals on different time scales. It will be the generalization of the correlation between pairwise time series and can be used to measure the multivariate correlation between the dependent variable y with the others i independent variable x. To validate the DMMC method, we determined the DMMC coefficient into numerical simulations on the standard Gaussian distribution, Lognormal distribution t distribution and ARFIMA long memory random sequences. Then we apply the proposed method to explore the multiple correlations between China's Shanghai, Shenzhen, and Hong Kong stock markets and analyze the dynamic time-varying characteristics of the correlation with the sliding window approach. The results show that DMMC is suitable to measure multiple cross-correlations. This new method can be further applied to multiple cross-correlation in different areas of knowledge, such as energy, meteorology, medicine, transportation, etc. • We proposed a new detrended multiple moving average cross-correlation coefficient. • We performed numerical simulations under different distributions. • The results are presented in a new map of colors. [ABSTRACT FROM AUTHOR]

Cu films were deposited on the silicon substrate at ground potential by bipolar pulse and conventional HiPIMS configurations in combination with different bias voltages. The fraction and energy of ion bombardment were tailored using different control strategies. The increasing deposition rate mechanism for bipolar pulse HiPIMS was discussed based on a phenomenological equilibrium analytical model. The morphology, structure, stress, electrical and mechanical properties of Cu films were investigated. Our results show that the positive pulse has a minor influence on the ionization rate of target materials in plasma, but it can effectively resist the ions back and drive them to arrive at the substrate during the deposition process. The deposition rate improves by ~ 55% for KP100 and KV100 samples than CHiPIMS. The positive reversed pulse in the whole pulse-off time benefits a compact microstructure, smooth surface morphology and minor residual tensile stress for Cu films due to the high energy of accelerating ions. Cu films prepared by BPH method exhibit good adhesion strength, electrical and tribological properties. When the kick voltage increases to 50 V with a constant kick pulse length, the critical load for the copper film reaches 10 N, and the COF is also the lowest. The high bias voltage causes a rising coefficient of friction, likely due to cavities on the film's surface. [ABSTRACT FROM AUTHOR]

SUMMARY: Rice (Oryza sativa L.) is a short‐day plant whose heading date is largely determined by photoperiod sensitivity (PS). Many parental lines used in hybrid rice breeding have weak PS, but their F1 progenies have strong PS and exhibit an undesirable transgressive late‐maturing phenotype. However, the genetic basis for this phenomenon is unclear. Therefore, effective methods are needed for selecting parents to create F1 hybrid varieties with the desired PS. In this study, we used bulked segregant analysis with F1 Ningyou 1179 (strong PS) and its F2 population, and through analyzing both parental haplotypes and PS data for 918 hybrid rice varieties, to identify the genetic basis of transgressive late maturation which is dependent on dominance complementation effects of Hd1, Ghd7, DTH8, and PRR37 from both parents rather than from a single parental genotype. We designed a molecular marker‐assisted selection system to identify the genotypes of Hd1, Ghd7, DTH8, and PRR37 in parental lines to predict PS in F1 plants prior to crossing. Furthermore, we used CRISPR/Cas9 technique to knock out Hd1 in Ning A (sterile line) and Ning B (maintainer line) and obtained an hd1‐NY material with weak PS while retaining the elite agronomic traits of NY. Our findings clarified the genetic basis of transgressive late maturation in hybrid rice and developed effective methods for parental selection and gene editing to facilitate the breeding of hybrid varieties with the desired PS for improving their adaptability. Significance Statement: We identified the genetic basis of transgressive late maturation in hybrid rice, which is dependent on dominance complementation effects of Hd1, Ghd7, DTH8, and PRR37 from both parents and developed effective methods for parental selection and gene editing to facilitate the breeding of hybrid varieties with the desired photoperiod sensitivity. Our study lays an important foundation for improving the breeding efficiency and latitude adaptability of hybrid rice. [ABSTRACT FROM AUTHOR]

• A new kind of carbon nanofibers bearing Fe/Co alloy nanoparticles is fabricated. • Fe/Co-CNFs electrode achieves a total degradation of tetracycline into CO 2 and H 2 O. • Fe/Co-CNFs display outstanding stability, recyclability and reusability. Rough surfaced carbon nanofibers bearing evenly distributed iron/cobalt alloy nanoparticles (Fe/Co-CNFs) are developed through the electrospinning of polyvinylpyrrolidone (PVP) mingled with 5.0 wt% of total ferric nitrate and cobalt nitrate concentration, followed by direct calcination of PVP composite nanofibers at 800 °C for 30 min in a reduction atmosphere. With a large specific surface area and active sites, the Fe/Co-CNFs could serve as an excellent anode material for the complete electrocatalytic degradation of tetracycline into carbon dioxide and water at a bias voltage of 1.0 V (vs. SCE) in a solution with pH value of 5.0 and 0.1 mol L−1 Na 2 SO 4 as the supporting electrolyte. The observed tetracycline degradation percentage of 97.55% even after ten cycles of electrocatalytic process for Fe/Co-CNFs modified electrode indicates an excellent stability, recyclability, and reusability. This work provides a novel material for environmental remediation of antibiotic contaminated water. [ABSTRACT FROM AUTHOR]

Metal oxides were emerging as persulfate (PS) catalysts in advanced oxidation processes, facilitating the degradation of recalcitrant pollutants. A novel iron/manganese (Fe/Mn) binary oxide catalyst was synthesized using a straightforward ultrasound-hydrothermal method in this study. The successful preparation of the material was also verified by XRD, HRTEM, EF-TEM, STXM, FTIR and the adsorption properties of the material were characterized. The removal of tetrabromobisphenol A (TBBPA) by Fe/Mn binary oxide and PS system was systematically investigated by changing the reaction parameters including Fe/Mn ratio in the catalyst, PS dosages and solution pH. The results indicated that the degradation percentage of TBBPA increased with higher PS dosage and reached its maximum at a solution pH of 8.0 with Fe/Mn-1.0. The highest removal ratio of TBBPA could be reached up to 90.50%. Finally, the intermediate products were identified and the degradation pathways were proposed. Remarkably, a low metal leaching ratio at different solution pH values was revealed by the Fe/Mn binary oxide, demonstrating high stability. This study paves the way for a novel approach to the heterogeneous activation of persulfate using a low-cost, environmentally friendly, and high-performance catalyst for the degradation of persistent pollutants. [Display omitted] • Fe/Mn binary oxide is prepared for activating persulfate to degrade TBBPA. • Sulfate and hydroxyl radicals are reactive species for degradation mechanism. • Degradation pathways are speculated with several typical intermediates identified. • Fe/Mn binary oxide exhibits high catalytic efficiency and long-term stability. [ABSTRACT FROM AUTHOR]

Herein, we report the first example of controllable magnetoresistance in a semiconducting carbonized phthalonitrile resin. This special phenomenon is explained using the different ratios of graphite-like (sp2) and diamond-like (sp3) bonds and localization length (a0) as well as the density of states at the Fermi-level (N(EF)). [ABSTRACT FROM AUTHOR]

Key message: We clarify the influence of the genotypes of the heading date genes Hd1, Ghd7, DTH8, and PRR37 and their combinations on yield-related traits and the functional differences between different haplotypes. Heading date is a key agronomic trait in rice (Oryza sativa L.) that determines yield and adaptability to different latitudes. Heading date 1 (Hd1), Grain number, plant height, and heading date 7 (Ghd7), Days to heading on chromosome 8 (DTH8), and PSEUDO-RESPONSE REGULATOR 37 (PRR37) are core rice genes controlling photoperiod sensitivity, and these genes have many haplotypes in rice cultivars. However, the effects of different haplotypes at these genes on yield-related traits in diverse rice materials remain poorly characterized. In this study, we knocked out Hd1, Ghd7, DTH8, or PRR37, alone or together, in indica and japonica varieties and systematically investigated the agronomic traits of each knockout line. Ghd7 and PRR37 increased the number of spikelets and improved yield, and this effect was enhanced with the Ghd7 DTH8 or Ghd7 PRR37 combination, but Hd1 negatively affected yield. We also identified a new weak functional Ghd7 allele containing a mutation that interferes with splicing. Furthermore, we determined that the promotion or inhibition of heading date by different PRR37 haplotypes is related to PRR37 expression levels, day length, and the genetic background. For rice breeding, a combination of functional alleles of Ghd7 and DTH8 or Ghd7 and PRR37 in the hd1 background can be used to increase yield. Our study clarifies the effects of heading date genes on yield-related traits and the functional differences among their different haplotypes, providing valuable information to identify and exploit elite haplotypes for heading date genes to breed high-yielding rice varieties. [ABSTRACT FROM AUTHOR]

A high step-up dc–dc converter is proposed in this article. With magnetic-coupling-based voltage multiplier technique, the proposed converter achieves high voltage gain and low switch voltage stress. Also, due to a boost inductor at the input, continuous input current is obtained, which is beneficial for battery, fuel cell, and photovoltaic applications. Moreover, zero voltage switching of the mosfets is achieved, leading to low switching losses. Furthermore, zero dc bias of the coupled inductor is realized, resulting in small magnetic size and low core losses. The operation principles, performance analysis, and design considerations of the proposed converter are discussed. A prototype with 40-V input and 400-V output has been developed to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

Prurigo nodularis is a skin disease with unknown origin which is frequent in patients on maintenance renal replacement therapy. Here, we report a patient who was dialyzed for more than 10 years with different dialyzers using different dialyzer membranes. Each time when the patient was switched to a polymethylmethacrylate membrane (Filtryzer BK-1.6P), itching and skin lesions disappeared completely. This effect could be verified three times. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Magnetron sputtered TiNi thin films usually exhibit an amorphous structure and need a high substrate temperature (>450 °C) or a post-annealing treatment (>500 °C) to promote crystallization. However, these treatments could extremely limit the use of low melting point substrate materials. In this study, TiNi thin films were prepared by HiPIMS using different deposition parameters. The structure and phase transformation of TiNi films were investigated. Based on SEM, XRD, TEM, DSC and electrical resistivity analysis, results show that it is possible to deposit dense crystalline TiNi thin films at a low substrate temperature (230 °C). The crystallization mechanism was also discussed. Ions energy and substrate temperatures significantly affected the formation of crystalline structures. • Crystalline TiNi thin films were prepared by HiPIMS at a low substrate temperature (230 °C). • Microstructure and crystalline mechanism of TiNi thin films were investigated. • The substrate temperature and bias voltage play important roles on the formation of crystalline TiNi films. [ABSTRACT FROM AUTHOR]

A latex agglutination test (LAT) was developed for the rapid detection of antibodies against the VP1 or VP1 proteins of Enterovirus 71 (EV71). The proteins of interest including prokaryotically expressed VP1 and two strains of anti-VP1 monoclonal antibody (McAb) against EV71 were covalently linked to carboxylated latex using ethyl-dimethyl-amino-propyl carbodiimide (EDC) to prepare sensitized latex beads. LAT was evaluated by an enzyme-linked immunosorbent assay (ELISA) as a reference test. The VP1-LAT showed a sensitivity of 87.0%, specificity of 88.9%, and an agreement ratio of 90.0% in detecting VP1 in 100 serum samples from experimentally infected mice, whereas these values were 86.8, 96.7, and 93.3%, respectively, for 608 clinical human serum samples. The VP1-LAT has advantages over other assays in terms of low cost, rapidity, chemical stability, high sensitivity, repeatability, and specificity. The LAT established in the present study is a rapid and simple test suitable for field monitoring of antibodies against VP1-EV71. [ABSTRACT FROM AUTHOR]

• The plate responses to complicated elastic-plastic impacts are characterized. • The existing impact characterization diagram is examined for three contact types. • The extended impact characterization diagram is proposed. • The proposed diagram is robust in identifying the plate impact responses. • The proposed diagram is efficient in fast predicting the maximum impact force. This paper presents a study on the characterization of low-velocity and low-energy impact responses of elastic-plastic plate struck by elastic-plastic spherical impactor. The applicability of the existing impact characterization diagram is examined firstly by intensive finite element (FE) simulations for a wide range of complicated impact situations including all three types of contact: indentation, flattening and combined flattening and indentation. The limitations of the existing diagram are found in identifying the type of impact response and predicting the maximum impact force for complicated impact situations. The effects of elastic and plastic deformations of impactor on the identification and prediction by the existing diagram are analyzed. A new linear contact law is presented according to the piecewise linear characteristics of contact stiffness observed from the intensive FE results. An extended impact characterization diagram is then proposed to characterize low-velocity and low-energy impact responses of plate under complicated impact situations with arbitrary three contact types. The extended diagram is validated by the intensive FE simulations and experimental results. It is concluded that the extended impact characterization diagram can identify correctly the plate response type to complicated impacts and predict accurately the maximum impact force in a fast and simple way without the aid of FE models and experimental tests. [ABSTRACT FROM AUTHOR]

Phase change energy storage is a new type of energy storage technology that can improve energy utilization and achieve high efficiency and energy savings. Phase change hysteresis affects the utilization effect of phase change energy storage, and the influencing factors are unknown. In this paper, a low-temperature eutectic phase change material, CaCl2·6H2O-MgCl2·6H2O, was selected as the research object, combined with the mechanism of phase change hysteresis characteristics, using a temperature acquisition instrument to draw the step cooling curve. A differential scanning calorimeter was used to measure the DSC (differential scanning calorimetry) curve, and the hysteresis characteristics of phase transformation were studied by factors, such as heat storage temperature, cooling temperature, and cooling rate. The experimental results show that when heating temperature increases by 30 °C, phase transition hysteresis decreases by about 3 °C. The cooling temperature decreased by 10 °C, and the phase transition hysteresis increased by 2.69 °C. This paper provides a new idea for optimizing the properties of phase change energy storage materials and provides a possibility for realizing the parametric control of phase change hysteresis factors. [ABSTRACT FROM AUTHOR]

We propose a strategy to improve the TE performance of Bi 0.4 Sb 1.6 Te 3 (BST) using cold pressing and thermal annealing. This process has the advantages of low-cost, time saving, and suitable for large-scale preparation. The BST alloy exhibits exceptional TE performance, achieving a maximum ZT of ∼1.27 at 333 K. Furthermore, the fabricated TE module demonstrates a high output power density of 12.62 mW/cm2 with a temperature difference of 30 K, enabling direct utilization of human skin heat for powering electronic devices. [Display omitted] • Bi 0.4 Sb 1.6 Te 3 allay is prepared by a low-cost cold pressing and annealing method. • A optimal ZT value of ∼1.27 at 60 °C is achieved. • An ultra-high output power density of 12.62 mW/cm2 with a temperature difference of 30 K. • TEG can directly harvest heat from human skin to power electronic devices. • The TE module active cooling of human skin and achieve a cooling effect of ∼8.0 °C. Manufacturing low-cost, high-performance thermoelectric (TE) modules is essential for power generation and cooling. However, traditional fabrication methods (zone melting and hot pressing) are time-consuming and expensive, and the fabricated Bi 2 Te 3 -based materials have unsatisfied performance. Herein, Bi 0.4 Sb 1.6 Te 3 alloys with high TE properties were prepared using cold pressing and thermal annealing processes. This preparation process is simple, time saving, and suitable for large-scale promotion. The annealing process induces the formation of pores within the grain interface, which effectively scatters low-energy charge carriers and enhance the phonon scattering. Although the electrical properties is reduced, the improved Seebeck coefficient compensates for the deteriorated electrical properties. Meanwhile, the thermal conductivity is significantly reduced. Eventually, a peak ZT of ∼1.27 is achieved at 333 K. The TE modules assembled with our Bi 0.4 Sb 1.6 Te 3 alloy exhibit high output and cooling performance, with an output power density of 12.62 mW/cm2 with a temperature difference of 30 K. Furthermore, the TE module can be used for the active cooling of human skin and achieve a cooling effect of ∼8.0 °C. These results indicate that our samples are suitable for the preparation of commercially applicable TE modules and as power sources for next-generation wearable electronic devices. [ABSTRACT FROM AUTHOR]

With the reduction and depletion of shallow energy, the mining depth of coal around the world is increasing year by year, and the mining depth of some coal mines in China has reached kilometers. The main roadway near the goaf with the deep high static stress is very easy to be damaged after being disturbed by the mine earthquake. Taking the main roadway in the no. 1 mining area of Gaojiapu coal mine in Binchang mining area, Shaanxi Province, China, as the engineering background, the high-energy mine earthquake monitored by the on-site microseism is equivalently simulated through the dynamic module of FLAC3D, and the spatial-temporal rotation characteristics of the principal stress of roadway surrounding rock under the disturbance of mine earthquake are studied and analyzed and put forward corresponding prevention and control measures. Research shows early stage of mine earthquake disturbance, roadway roof is first affected, and the principal stress of the roof has the trend of deflection to the side of the goaf. In the middle stage of mine earthquake disturbance, the main body of roof principal stress deflects to the side of goaf, and the deflection range is large. In the later stage of mine earthquake disturbance, the principal stress directions in the surrounding rock reverse rotation, and the reverse rotation angle of the principal stress direction in the roof is the largest. Finally, the asymmetric distribution characteristics of principal stress rotation are verified by using the asymmetric deformation phenomenon on both sides of roadway surrounding rock. Based on the rotation characteristics of principal stress under the dual influence of mine earthquake disturbance and goaf, optimize the layout scheme and blasting parameters of blasting pressure relief holes. The transmission direction of principal stress can be changed by blasting pressure relief method; meanwhile, the transmission of principal stress can be blocked; through the comparison of microseismic activity law before and after pressure relief, pressure relief effect is good. The research results can provide a certain reference basis for coal mine roadway pressure relief and reducing disaster conditions. [ABSTRACT FROM AUTHOR]

With the reduction and depletion of shallow energy, the mining depth of coal around the world is increasing year by year, and the mining depth of some coal mines in China has reached kilometers. The main roadway near the goaf with the deep high static stress is very easy to be damaged after being disturbed by the mine earthquake. Taking the main roadway in the no. 1 mining area of Gaojiapu coal mine in Binchang mining area, Shaanxi Province, China, as the engineering background, the high-energy mine earthquake monitored by the on-site microseism is equivalently simulated through the dynamic module of FLAC3D, and the spatial-temporal rotation characteristics of the principal stress of roadway surrounding rock under the disturbance of mine earthquake are studied and analyzed and put forward corresponding prevention and control measures. Research shows early stage of mine earthquake disturbance, roadway roof is first affected, and the principal stress of the roof has the trend of deflection to the side of the goaf. In the middle stage of mine earthquake disturbance, the main body of roof principal stress deflects to the side of goaf, and the deflection range is large. In the later stage of mine earthquake disturbance, the principal stress directions in the surrounding rock reverse rotation, and the reverse rotation angle of the principal stress direction in the roof is the largest. Finally, the asymmetric distribution characteristics of principal stress rotation are verified by using the asymmetric deformation phenomenon on both sides of roadway surrounding rock. Based on the rotation characteristics of principal stress under the dual influence of mine earthquake disturbance and goaf, optimize the layout scheme and blasting parameters of blasting pressure relief holes. The transmission direction of principal stress can be changed by blasting pressure relief method; meanwhile, the transmission of principal stress can be blocked; through the comparison of microseismic activity law before and after pressure relief, pressure relief effect is good. The research results can provide a certain reference basis for coal mine roadway pressure relief and reducing disaster conditions. [ABSTRACT FROM AUTHOR]

With the reduction and depletion of shallow energy, the mining depth of coal around the world is increasing year by year, and the mining depth of some coal mines in China has reached kilometers. The main roadway near the goaf with the deep high static stress is very easy to be damaged after being disturbed by the mine earthquake. Taking the main roadway in the no. 1 mining area of Gaojiapu coal mine in Binchang mining area, Shaanxi Province, China, as the engineering background, the high-energy mine earthquake monitored by the on-site microseism is equivalently simulated through the dynamic module of FLAC3D, and the spatial-temporal rotation characteristics of the principal stress of roadway surrounding rock under the disturbance of mine earthquake are studied and analyzed and put forward corresponding prevention and control measures. Research shows early stage of mine earthquake disturbance, roadway roof is first affected, and the principal stress of the roof has the trend of deflection to the side of the goaf. In the middle stage of mine earthquake disturbance, the main body of roof principal stress deflects to the side of goaf, and the deflection range is large. In the later stage of mine earthquake disturbance, the principal stress directions in the surrounding rock reverse rotation, and the reverse rotation angle of the principal stress direction in the roof is the largest. Finally, the asymmetric distribution characteristics of principal stress rotation are verified by using the asymmetric deformation phenomenon on both sides of roadway surrounding rock. Based on the rotation characteristics of principal stress under the dual influence of mine earthquake disturbance and goaf, optimize the layout scheme and blasting parameters of blasting pressure relief holes. The transmission direction of principal stress can be changed by blasting pressure relief method; meanwhile, the transmission of principal stress can be blocked; through the comparison of microseismic activity law before and after pressure relief, pressure relief effect is good. The research results can provide a certain reference basis for coal mine roadway pressure relief and reducing disaster conditions. [ABSTRACT FROM AUTHOR]

Summary: Rice (Oryza sativa) is a short‐day (SD) plant originally having strong photoperiod sensitivity (PS), with SDs promoting and long days (LDs) suppressing flowering. Although the evolution of PS in rice has been extensively studied, there are few studies that combine the genetic effects and underlying mechanism of different PS gene combinations with variations in PS.We created a set of isogenic lines among the core PS‐flowering genes Hd1, Ghd7 and DTH8 using CRISPR mutagenesis, to systematically dissect their genetic relationships under different day‐lengths. We investigated their monogenic, digenic, and trigenic effects on target gene regulation and PS variation.We found that Hd1 and Ghd7 have the primary functions for promoting and repressing flowering, respectively, regardless of day‐length. However, under LD conditions, Hd1 promotes Ghd7 expression and is recruited by Ghd7 and/or DTH8 to form repressive complexes that collaboratively suppress the Ehd1‐Hd3a/RFT1 pathway to block heading, but under SD conditions Hd1 competes with the complexes to promote Hd3a/RFT1 expression, playing a tradeoff relationship with PS flowering. Natural allelic variations of Hd1, Ghd7 and DTH8 in rice populations have resulted in various PS performances.Our findings reveal that rice PS flowering is controlled by crosstalk of two modules – Hd1–Hd3a/RFT1 in SD conditions and (Hd1/Ghd7/DTH8)–Ehd1–Hd3a/RFT1 in LD conditions – and the divergences of these genes provide the basis for rice adaptation to broad regions. [ABSTRACT FROM AUTHOR]

In this study, Nd and As are mainly sealed into industrial pure Fe cylinders. The effect of different temperatures on the high-temperature interaction of an Nd–Fe–As ternary system is studied via X-ray diffraction, optical microscopy, and scanning electron microscopy after heat insulation for 30 h at 1173, 1223, and 1273 K. The results show that the common products under high-temperature interaction are NdAs, Fe17Nd2, and Fe. Fe12As5 is present at 1173 K, whereas Fe2As is produced at 1223 and 1273 K. The diffusion ability of Nd is weaker than that of As. Nd mainly diffuses through the Fe atomic vacancy mechanism. As mainly binds to Fe to form Fe and As compounds. [ABSTRACT FROM AUTHOR]

The Cuk dual resonance core (DRC) realizes overlapped dual resonance to regulate its output voltage. However, the DRC configuration was only applied to the Fibonacci switched-capacitor converter (SCC), series–parallel SCC, and voltage doubler. In this paper, the Cuk DRC is modified and then is extended to the Dickson SCC to form a multi-resonance-core-based (MRC) Dickson resonant switched-capacitor converter. All charging and discharging loops achieve soft charging, and so the inherent capacitor charge sharing loss and the high current transient spikes are eliminated. The modular configuration makes the MRC Dickson easy to be extended to a higher voltage level. The on-time fixed frequency modulation is adopted, all transistors being turned on with zero-current-switching (ZCS) operation and all diodes being turned off with ZCS operation. Most importantly, the conversion ratio of the MRC Dickson can be regulated continuously, widely, and efficiently even at light load condition, which is a huge advantage over the traditional Dickson SCC with limited control headroom. A comprehensive analysis of the operation principle, voltage-gain curve, component stress analysis, and output characteristic is provided. The converter operation principle and regulation capability were verified by both simulation and experiment. [ABSTRACT FROM AUTHOR]

Thermal decomposition behaviors of textile dyeing sludge (TDS), pomelo peel (PP), and their blends (TP) were detected using TG-FTIR. The blend ratios of TDS to PP ranged from 10 to 40 wt% and were subjected to heat above room temperature up to 1000 °C under four heating rates. Our results pointed to four stages for TDS combustion and three stages for PP combustion. The interactions between TDS and PP exerted inhibitive effects during the co-combustion process. Releases of CO 2 and light organics occurred less with a TP ratio of 70%–30% (TP73) than with the individual fuels. Apparent activation energy ( E a ) was obtained using Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods. The FWO-based E a estimates were in the range of 59.7–122.2 kJ·mol −1 for TDS, 84.4–243.5 kJ·mol −1 for PP, and 94.3–142.1 kJ·mol −1 for TP73. [ABSTRACT FROM AUTHOR]

Co-combustion characteristics of textile dyeing sludge (TDS) and pomelo peel (PP) under O 2 /N 2 and O 2 /CO 2 atmospheres were investigated using a thermogravimetric analysis (TGA) and artificial neural networks. 30% O 2 /70% CO 2 and air atmospheres led to a similar co-combustion performance. Increases in O 2 concentration and PP significantly improved the oxy-fuel co-combustion performance of TDS. Principal component analysis was applied to reduce the dimensionality of differential TGA curves and to identify the principal reactions. The interaction between TDS and PP occurred mainly at 490–600 °C, thus improving the process of residue co-combustion. Radial basis function was found to have more reliable and robust predictions of TGA under different O 2 /CO 2 atmospheres than did Bayesian regularized network. Regardless of Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods used, the lowest mean value of apparent activation energy (155.4 kJ·mol −1 by FWO and 153.2 kJ·mol −1 by KAS) was obtained under the 30% O 2 /70% CO 2 atmosphere. [ABSTRACT FROM AUTHOR]

• An experimental analysis is presented for the dynamic behavior of elastic visco-plastic beam under repeated impacts at different impact positions. • The effects of repeated impacts and impact positions on the sub-impact behaviors and wave propagations, high-frequency vibrations and long-term beam responses are analyzed. • Two influence modes of repeated impacts with the deterministic and random features are observed. • The couplings of sub-impacts, wave propagation and high-frequency vibrations make the repeated-impact behavior much more complicated. Repeated impact behaviors of an elastic visco-plastic steel beam struck by a hard sphere are experimentally examined in this paper. The interaction between impact bodies, behaviors of sub-impacts, wave propagations and dynamics of the beam are tested to get a better understanding into the mechanism of repeated impacts. At the four different impact locations on the beam, thirty repeated-mass-impact tests are conducted for each impact location under identical initial conditions except for the accumulated deformations. The effects of repeated impacts and impact location on the sub-impact behaviors, local contact deformations, wave propagations, high-frequency vibrations and long-term beam responses are analyzed. The sub-impact phenomenon is observed. The deterministic and random features of the influences of repeated impacts on the behaviors of sub-impacts are observed. The deterministic feature similar to the elastic shakedown phenomenon is found to occur for the first sub-impact behaviors, such as the kinetic coefficient of restitution, residual deformations and early wave propagations. The random feature is found to occur for the second sub-impact behaviors as well as the vibrational modes and long-term stress and displacement responses. The couplings of sub-impacts, wave propagation and high-frequency vibrations make the repeated impact behaviors of flexible structure much more complicated than single impact. [ABSTRACT FROM AUTHOR]

• Numerical analysis of plastic yield behavior in early impact stage based on mesh-refined FE models. • Newly observed characteristics of dynamic stress responses in early impact stage. • Newly observed evolution modes of initial plastic zone and analysis of plastic yield mechanism. • Single-valued dependence of critical impact parameters on normalized impact velocity. • Newly proposed velocity criterion for quasi-static impact by considering the limitation of plastic yield. This paper investigates the plastic yield behavior during the supersonic, transonic and subsonic stages of impact. The frictionless impacts of a rigid sphere on an elastic-perfectly plastic half-space are simulated by the mesh-refined finite element (FE) models without the assumption of the rigid sphere moving at constant velocity. The dynamical characters of stress field and evolutions of the initial plastic zone are analyzed based on the simulations of a wide range of materials and impact velocities. The plastic yielding is found to occur at all the stages of impact. The present investigation shows that impact-induced waves and fast expansion of contact region have great influence on the high stress regions and the evolution modes of the initial plastic zone. A determination method for the stable yield inception is proposed to avoid the disturbances of the observed local unloading at the beginning of the main plastic zone. The critical parameters at the yield inception are extracted and their dependences upon the normalized impact velocity are analyzed. By considering the limitation of the plastic yield, a new velocity criterion is proposed to solve the critical impact parameters by the quasi-static impact theory. The present investigation shows that the impact with relative high impact velocity makes the plastic yielding shallower and reduces greatly the impact force and dynamic indentation required for yielding. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The magnetic amorphous carbon@manganese ferrite (C@MnFe 2 O 4) hybrid materials were fabricated. • C@MnFe 2 O 4 is an effective persulfate (PS) activator with high stability. • The total organic carbon mineralization in C@MnFe 2 O 4 activated PS system reached 50.1% • Possible degradation pathways of TBBPA in the C@MnFe 2 O 4 activated PS system were proposed. Tetrabromobisphenol A (TBBPA), a typical brominated flame retardant in industry, has been recognized as a toxic chemical and an endocrine disruptor. Hence, it's urgently required to remove it from aquatic environment. In this work, the magnetic amorphous carbon@manganese ferrite (C@MnFe 2 O 4) hybrid materials have been fabricated by hydrothermal method with high temperature annealing method to serve as catalyst for the activation of persulfate (PS) to degrade the TBBPA. The structure characterization results manifest that the synthesized MnFe 2 O 4 particles are evenly distributed on the surface of amorphous carbon in the C@MnFe 2 O 4 hybrid. The factors to affect the catalytic degradation of TBBPA by C@MnFe 2 O 4 hybrid/PS system including type of C@MnFe 2 O 4 hybrid materials, PS dosage, concentration of C@MnFe 2 O 4 and reaction time are investigated systematically. The results show that the highest removal ratio of TBBPA could reach 91.9% after treatment of 90 min by C@MnFe 2 O 4 hybrid/PS system. Furthermore, the C@MnFe 2 O 4 hybrid demonstrates a high stability and recyclability. The electron paramagnetic resonance (EPR) verifies that the introduction of C@MnFe 2 O 4 hybrid into PS system could facilitate the generation of ⋅OH and SO 4 ⋅- radicals for degradation of TBBPA. The degradation intermediates are detected and two possible degradation pathways are proposed. This work provides a new insight for the design and development of novel catalyst for the activation of PS to degrade organic pollutants. [ABSTRACT FROM AUTHOR]