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Two-dimensional (2D) magnets have attracted significant attention in recent years due to their importance in the research on both fundamental physics and spintronic applications. Here, we report the discovery of a new ternary compound FePd2Te2. It features a layered quasi-2D crystal structure with 1D Fe zigzag chains extending along the b-axis in the cleavage plane. Single crystals of FePd2Te2with centimeter size could be grown. Density functional theory calculations, mechanical exfoliation, and atomic force microscopy on these crystals reveal that they are 2D materials that can be thinned down to ∼5 nm. Magnetic characterization shows that FePd2Te2is an easy-plane ferromagnet with TC∼ 183 K and strong in-plane uniaxial magnetic anisotropy. Magnetoresistance and the anomalous Hall effect demonstrate that ferromagnetism could be maintained in FePd2Te2flakes with large coercivity. A crystal twinning effect is observed by scanning tunneling microscopy which makes the Fe chains right angle bent in the cleavage plane and creates an intriguing spin texture. Besides, a large electronic specific heat coefficient of up to γ ∼ 32.4 mJ mol–1K–2suggests FePd2Te2is a strongly correlated metal. Our results show that FePd2Te2is a correlated anisotropic 2D magnet that may attract multidisciplinary research interests.

Due to the integration and utilization of the parasitic capacitance of the transformer, the LCC resonant converters with a capacitive output filter are widely used in high-voltage power supplies for microwave generation, X-ray, ion implantation, and other fields. However, it is challenging for the LCC to maintain high efficiency in a wide output voltage range. In this article, an optimal control coordinate trajectories (OCCTs)-based phase-shift pulse-frequency modulation (PS-PFM) control method is proposed to achieve high efficiency by reducing the switching frequency range and the turn-off current. With the normalized time-domain analysis, the operation stage trajectories of LCC and their boundary conditions under the PS-PFM control are derived. Based on this, the OCCTs of the switching frequency and the duty cycle at different voltage gains are precisely calculated. By associating the duty cycle with the switching frequency and the output voltage gain through a fit equation based on the OCCTs data, the proposed PS-PFM control strategy can adaptively adjust the optimal duty cycle, simplifying one of the control freedom degrees. Then, an optimization design algorithm for the resonant network parameter is proposed to reduce the conduction loss of LCC. Finally, a 10–20-kV/15-kW LCC resonant high-voltage power supply prototype is built to verify the feasibility of the proposed control strategy.

For the conventional single-phase current source inverter (CSI), a large inductor is needed to stabilize the input current, which increases system volume, cost, and losses. In this article, a single-phase single-stage CSI with its operation principle is proposed. Different from conventional CSIs where only voltage-boost operation is supported, the input dc-link voltage of the proposed CSI can be higher than the peak value of output voltage (buck mode), and it can also be lower than the peak value of output voltage (boost mode). So, it is very suitable for occasions with a wide input voltage range. Moreover, the input inductor current can be balanced within per switching cycle using the proposed operation strategy. As a result, the input inductor and output filter capacitor are decreased. First, the derivation and operating modes of the CSI are given in detail. Then, the design guidelines of the components are presented, and a comparison with some existing CSIs has been made. A 1 kW prototype is also built and tested in the laboratory, the experimental results are presented to verify the effectiveness of the proposed CSI and control strategy.

Ultrasmall amounts of P-doping regulate the electronic structure of Ni/mSiO2and allow the tilted adsorption configuration of furfural for promoting hydrogenation rearrangement of furfural to cyclopentanone.

The development of cost-effective and efficient catalysts plays a critical role in the selective hydrodeoxygenation of lignin derivatives for lignin valorization. Herein, we reported “metal-acid” bifunctional catalysts (Ni/Ti-SBA-15) consist of Ni nanoparticles highly dispersed on Ti doped SBA-15, which achieved 100% vanillin conversion and 96.46% selectivity of 2-methoxy-4-methylphenol (MMP) under mild conditions. Characterizations were employed to reveal the morphology and physicochemical properties of the catalysts. The results indicated that doping of Ti species not only increased the number of acidic sites but also promoted the high dispersion of Ni nanoparticles on the support. This research provides a novel concept for the synthesis of cost-effective and efficient catalysts, which contributes to the environmentally friendly and economical conversion of biomass derivatives.

Ten-switch three-phase three-level inverter (TP-TLI) is receiving more attention owing to the reduced system cost compared to traditional TP-TLIs. However, it still faces serious neutral-point voltage (NPV) balance problems. This article proposes a novel virtual space vector modulation (NVSVM) with optimized neutral-point voltage control (NPVC) capability. A set of virtual vectors are selected to generate zero NP current. By analyzing the vector synthesis principle over the full modulation areas, a new control degree, which is utilized to optimize the NPVC capability and reduce line voltage total harmonic distortion (THD), is introduced. Besides, a dead time compensation method based on volt–second balance is also given to reduce the switching loss. The NVSVM not only improves the NPVC capability without dc offset and obvious ac oscillations in NPV under the full range of modulation index and power factor conditions but also reduces line voltage THD and the switching loss. Theoretical analysis shows that the available NP current for the proposed NVSVM is about 2.75 times greater at most than that for traditional VSVM. Simulation and experimental results are given to validate the effectiveness of the NVSVM and control strategies.

To meet the demand for seam tracking of welding robots, a deep learning-based framework called DeepKP is proposed in this article, which aims to precisely extract weld seam keypoints (WSKPs) under multiple arc light interference. DeepKP comprises a keypoint extraction model named WeldExt and a denoising model named WeldDenoise. WeldExt is proposed to identify weld seam types, obtain prior box region (PBR), and then extract keypoints in the region. WeldExt addresses the problem that most recent extraction models cannot directly obtain the keypoints. WeldDenoise is proposed for denoising weld seam images affected by multiple arc light interference, which overcomes the limitation that most recent denoising models must use paired datasets for training. Experiment results show that the average locating error of WSKP in WeldExt is 1.75 pixels and the average seam tracking error of DeepKp is 0.336 mm. Therefore, DeepKP performs excellently in extracting WSKPs under challenging arc light conditions and improves the quality of seam tracking.

The traditional torque sharing function (TSF) strategy can lead to large torque ripple and copper consumption in switched reluctance motors (SRMs) due to the limitation of the voltage in the phase change interval. In this paper, an improvement scheme is proposed to address this problem. First, a segmented non-linear correction TSF (SN-TSF) is proposed. Then with the torque ripple and copper consumption of the SRM as optimization objectives, the proposed SN-TSF values are optimized using the velocity control particle swarm optimization (VCPSO) algorithm based on the particle velocity–boundary relationship. The optimal parameters are used to obtain the optimal SN-TSF curves with different loading torques and speeds. Experimental results show that the proposed SN-TSF strategy reduces the torque ripple by 40.17% and 66.5%, and the peak phase currents by 5.058 A and 5.371 A under two different operating conditions, which demonstrates the effectiveness of this strategy.

Virtual space vector modulation (VSVM) is capable of suppressing neutral-point voltage (NPV) ripples in a coupled ten-switch three-phase three-level inverter. However, it presents a low NPV control (NPVC) speed. In this article, an enhanced VSVM (EVSVM) with the improved NPVC speed for balanced and unbalanced NPVs is proposed. By analyzing the features of the defined virtual vectors under the unbalanced NPV, the region division and duty ratio calculation are properly modified. Two coefficients are configured in the EVSVM. One distributes the duty ratios of two virtual small vectors to improve the NPVC speed, whereas another adjusts two pairs of redundant small vectors considering the NP current polarity to achieve accurate active NPVC. The highlight of this method is the improved NPVC speed and zero NP current in each switching cycle in a steady state. Theoretical analysis shows that the EVSVM increases the available NP current by 4.5% at least under a higher modulation index. Besides, the EVSVM could regulate the NPV without obvious ac ripples and dc offset under a full range of modulation index and power factor for both balanced and unbalanced NPVs. The feasibility and performance of the proposed modulation and control strategies are verified by a 3-kVA experimental prototype.

The hybrid-clamped three-level full-bridge LLC resonant converter is widely employed in subway power systems and ship-integrated power systems due to its notable attributes of soft switching and low input voltage requirements for the switching devices. Nonetheless, the existing wide voltage range modulation modes suffer from thermal imbalances in switching devices, posing limitations on their application in high-power scenarios. In order to address these issues, the three modulation modes optimized for thermal balance are proposed by analyzing the conditions for achieving soft-switching and thermal equalization. When integrated with the original modulation modes, these optimized modes effectively balance the conduction loss in the switching devices and achieve a wide range of voltage gain. Moreover, the proposed modulation transition method facilitates swift and efficient transitions between modulation modes, while minimizing the impact on voltage and current caused by the transition process. The experimental prototype with 1.5 kW power level and 125 V-1 kV input voltage range is built to verify thermal balance effect of switching devices under the proposed modulation mode and performance of the proposed modulation transition method.

Two-stage single-phase inverter using dual-mode control can match wide input voltage variation range and increase efficiency. That is studied by many researchers. In addition, using dual-mode control can improve the line-to-line output voltage waveform to be more easily filtered into sine wave. Thus, the traditional method to determine the LC filter parameters is unreasonable and will cause over filtering. The redundant design of filter will bring unnecessary volume, weight and loss on inductor and capacitor of the inverter, while decrease the power density. To solve this issue, this article derives the line-to-line output voltage harmonic components calculation formulas for the conventional two-stage inverter and the dual-mode inverter by using double Fourier integral analysis. By comparing the harmonic components calculation results around switching frequency, a new LC filter parameters design method for dual-mode inverter is proposed. Through the proposed method, the LC filter parameters are declined by 50%, which significantly reduces the volume, weight and cost of the inverter under other conditions of constant performance. Calculation and experimental results based on a 1 kW prototype verify the validity of the proposed method.

Gibberellin (GA) functions in plant growth and development. However, genes involved in the biosynthesis and regulation of GA in crop plants are poorly understood. We isolated the mutant gad5-1(GA-Associated Dwarf 5), characterized by dwarfing, short internodes, and dark green and short leaves. Map-based gene cloning and allelic verification confirmed that ZmGAD5encodes ent-kaurenoic acid oxidase (KAO), which catalyzes KA (ent-kaurenoic acid) to GA12 conversion during GA biosynthesis in maize. ZmGAD5 is localized to the endoplasmic reticulum and is present in multiple maize organs. In gad5-1, the expression of ZmGAD5is severely reduced, and the levels of the direct substrate of KAO, KA, is increased, leading to a reduction in GA content. The abnormal phenotype of gad5-1was restored by exogenous application of GA3. The biomass, plant height, and levels of GA12and GA3in transgenic Arabidopsisoverexpressing ZmGAD5were increased in comparison with the corresponding controls Col-0. These findings deepen our understanding of genes involved in GA biosynthesis, and could lead to the development of maize lines with improved architecture and higher planting-density tolerance.

Owing to the advantages of simple structure, higher power density, and reliability, unidirectional five-level rectifiers are attractive solutions for high-power medium-voltage nonregenerative applications such as electric vehicle charging pile, telecommunication power, and laser power. However, the existing five-level unidirectional rectifiers use more switching devices or flying capacitors (FCs). This will reduce the power density and increase the complexity of the system. To address this issue, this article presents a three-phase five-level unidirectional rectifier with reduced components. It uses only three active switches and one FC per phase. Compared with most similar rectifiers, the number of active switching devices and floating capacitors has been reduced by 25% and 50%, respectively. Consequently, the proposed rectifier has the comprehensive merits in terms of simple structure and higher power density of the system. The operating principles of the proposed topology, control strategy, modulation scheme, and comparison study are presented in depth. Finally, a 3 kW three-phase experimental prototype is built to verify the validity and flexibility of the proposed topology.

To realize high-quality robotic welding, an efficient and robust complex weld seam feature point extraction method based on a deep neural network (Shuffle-YOLO) is proposed for seam tracking and posture adjustment. The Shuffle-YOLO model can accurately extract the feature points of butt joints, lap joints, and irregular joints, and the model can also work well despite strong arc radiation and spatters. Based on the nearest neighbor algorithm and cubic B-spline curve-fitting algorithm, the position and posture models of the complex spatially curved weld seams are established. The robot welding posture adjustment and high-precision seam tracking of complex spatially curved weld seams are realized. Experiments show that the method proposed in this article can extract weld seam feature points quickly and robustly, which enables welding robots to accurately track the weld seams and adjust the welding torch postures simultaneously.

This article presents a method for computer-aided operation and design optimization of resonant converters using time-domain analysis. Resonant converters can operate in different operation stage trajectories (OSTs) with the change of two degrees of freedom (2DOFs), namely, switching frequency $f_{\mathrm {s}}$ and duty ratio $d$ . This article calculates and analyzes the operation characteristics, zero-voltage switching-ON (ZVS-ON) region, and zero-current switching-OFF (ZCS-OFF) region when the 2DOFs vary by solving the OST differential equation sets. Based on this analysis, an algorithm is proposed to find the operation and design optimizations of a specific resonant converter while considering 2DOFs by traversing all possible control coordinates. This article provides several case studies to demonstrate the design tradeoffs in different scenarios, which are verified through experimental verifications.

Ploidy manipulation has been used in many crop improvement programs to develop plant species with wider adaptability and desirable traits. The objectives of this study were to create stable tetraploid centipedegrass (Eremochloa ophiuroides[Munro] Hack.) lines and evaluate them for beneficial traits. To generate polyploid lines, “TifBlair” (2n= 2x= 18) seeds were exposed to gamma radiation and callus was generated using tissue culture, exposed to glyphosate and regenerated into plantlets. After 5 years of continuous propagation, two lines, Hongliang Wang (HW)16 and HW123, were found to be tetraploid, and one line, HW61, was found to be a mixoploid using flow cytometry and chromosome counts. Nuclear DNA contents for diploid and tetraploid lines ranged from 1.97 to 2.10 and 4.14 to 4.30 pg 2C−1, respectively. Ten centipedegrass lines were genotyped using seven simple sequence repeat markers and clustered by origin (derived from TifBlair or the University of Georgia breeding program). Six lines were evaluated for morphological and physiological traits under greenhouse conditions. Trait evaluation showed that tetraploid lines had larger stomata and leaf width and reduced stomatal density. For all other traits evaluated under greenhouse conditions, although significant differences were observed between lines, no consistent differences separated diploid and tetraploid lines. Between the tetraploid lines, HW16 had higher evapotranspiration, percentage green cover, and relative water content than HW123, whereas HW123 had a higher average clipping yield and root width than HW16. In conclusion, irradiation and tissue culture are valuable techniques for the generation of stable polyploid lines, and an increased ploidy level led to larger vegetative structures in centipedegrass. Two tetraploid and one mixoploid centipedegrass lines were created using irradiation and tissue culture.Nuclear DNA content for diploid and tetraploid lines ranged from 1.97 to 2.10 and 4.14 to 4.30 pg 2C−1, respectively.Tetraploid lines showed increased stomatal size and leaf width but less stomatal density than diploid lines.The tetraploid lines differed between each other for multiple morphological and physiological traits.

IMPORTANCE: Previous research has suggested that Xuebijing injection (XBJ), an herbal-based intravenous preparation, may reduce mortality among patients with sepsis. OBJECTIVE: To determine the effect of XBJ vs placebo on 28-day mortality among patients with sepsis. DESIGN, SETTING, AND PARTICIPANTS: The Efficacy of Xuebijing Injection in Patients With Sepsis (EXIT-SEP) trial was a multicenter, randomized double-blind, placebo-controlled trial conducted in intensive care units at 45 sites and included 1817 randomized patients with sepsis (sepsis 3.0) present for less than 48 hours. Patients aged 18 to 75 years with a Sequential Organ Failure Assessment score of 2 to 13 were enrolled. The study was conducted from October 2017 to June 2019. The final date of follow-up was July 26, 2019. Data analysis was performed from January 2020 to August 2022. INTERVENTIONS: The patients were randomized to receive either intravenous infusion of XBJ (100 mL, n = 911) or volume-matched saline placebo (n = 906) every 12 hours for 5 days. MAIN OUTCOMES AND MEASURES: The primary outcome was 28-day mortality. RESULTS: Among the 1817 patients who were randomized (mean [SD] age, 56.5 [13.5] years; 1199 [66.0%] men), 1760 (96.9%) completed the trial. In these patients, the 28-day mortality rate was significantly different between the placebo group and the XBJ group (230 of 882 patients [26.1%] vs 165 of 878 patients [18.8%], respectively; P < .001). The absolute risk difference was 7.3 (95% CI, 3.4-11.2) percentage points. The incidence of adverse events was 222 of 878 patients (25.3%) in the placebo group and 200 of 872 patients (22.9%) in the XBJ group. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial among patients with sepsis, the administration of XBJ reduced 28-day mortality compared with placebo. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03238742

Path tracking control technology is a hot topic in the research of intelligent vehicles. It is an important link to realize intelligent transportation to solve the problem of path tracking control for long-wheelbase vehicles. Aiming at the problem that the vehicle body of long wheelbase is prone to collision with the surrounding environment due to the influence of the vehicle axle length in the process of turning, the overall deviation model of vehicle wheelbase and reference path is creatively proposed, and the optimal heading angle of long-wheelbase vehicle in the process of turning is determined by solving the maximum value of the overall deviation model. The MPC path tracking controller is established based on the deviation between the heading angle and the actual vehicle. Eventually established more than a typical working condition in MATLAB and TRUCKSIM joint simulation, to verify the proposed algorithm not only has realized the long-wheelbase vehicle path tracking control and front wheel position closer to the reference curve, effective in reducing long-wheelbase vehicle steering wheel swept area, in the process of reducing long-wheelbase vehicle steering and road environment in the process of collision probability. It improves the trafficability of long-wheelbase vehicles in narrow areas.

Sika deerare known to prefer oak leaves, which are rich in tannins and toxic to most mammals; however, the genetic mechanisms underlying their unique ability to adapt to living in the jungle are still unclear. In identifying the mechanism responsible for the tolerance of a highly toxic diet, we have made a major advancement by explaining the genome of sika deer. We generated the first high-quality, chromosome-level genome assembly of sika deer and measured the correlation between tannin intake and RNA expression in 15 tissues through 180 experiments. Comparative genome analyses showed that the UGTand CYPgene families are functionally involved in the adaptation of sika deer to high-tannin food, especially the expansion of the UGTfamily 2 subfamily B of UGTgenes. The first chromosome-level assembly and genetic characterization of the tolerance to a highly toxic diet suggest that the sika deer genome may serve as an essential resource for understanding evolutionary events and tannin adaptation. Our study provides a paradigm of comparative expressive genomics that can be applied to the study of unique biological features in non-model animals.

Soft switching technology is an effective way to reduce the switching loss of the single-phase inverter to improve efficiency. Because of the ease of implementing soft switching, inverter works in boundary conduction mode (BCM) is widely used. On the contrary, BCM causes wide variation in switching frequency and large inductor current ripple. In this article, a fixed switching frequency hybrid modulation method for the inverter is proposed, which can achieve zero-voltage switching without changing the switching frequency and reduce the peak value of inductor current. The modulation achieves good tracking of the output current with different loads by switching mode between the triangular mode and the trapezoidal mode accurately. For implementing modulation, the operation states of the inverter with different conditions are analyzed in detail, the number of operation states is deduced and the state machine about mode switching is summarized. In addition, a single-phase inverter prototype is designed to verify the feasibility and effectiveness of the proposed modulation. Compared with BCM, the efficiency of the inverter at both light load and full load is increased.

Percarbonate has gradually emerged in the treatment of water pollution, and it is highly efficient, non-toxic, economical, and environmentally friendly. In this paper, 258 articles related to percarbonate from 2000 to 2022 were retrieved from the Web of Science. The contributing countries, institutions, authors, and journals were qualitatively and quantitatively analyzed by using CiteSpace software for the first time. The research hotspots and development trends in the field of percarbonate were proposed. The results showed that the research history of percarbonate can be divided into the initial stage (2000–2014) and rapid development stage (2015–2022). The countries which published the most papers are P. R. China, USA, and India. P. R. China is at the core of the international cooperation network. In particular, East China University of Science and Technology is leading in publication numbers and academic cooperation. The study of percarbonate was multidisciplinary and interdisciplinary, mainly concentrated in the disciplines of Environmental Sciences, Engineering Environmental, and Engineering Chemical. Research papers on percarbonate have been published in influential journals such as Chemical Engineering Journal, Chemosphere, and Science of the Total Environment. Keyword analysis indicated that percarbonate was initially used as an industrial oxygen source or organic synthesis material, and recently it was used for organic pollution remediation in groundwater and soil. The research hotspots in the field of percarbonate are concentrated on the activation method and mechanism of percarbonate, and the coupling with other processes such as membrane treatment. This paper can provide valuable references for research and application in the field of percarbonate.

From the perspective of practical application, a novel task allocation problem for multi-vehicle systems is proposed. The goal is to allocate an optimal route for each vehicle to execute tasks. The planning result is a comprehensive decision considering the influence of time windows, collaborative tasks, and recharging. This problem is represented as a new extension of the classical vehicle routing problem and a multi-objective integer programming mathematical model is established. The objective functions are the total completion time and total penalty costs. A solution strategy hybridizing non-dominated sorting genetic algorithm-II and variable neighborhood search is proposed, and a feasibility recovery strategy and the concept of the immigrant population are introduced. Finally, the simulation results show that the proposed algorithm can solve the problem effectively and is robust to different complexity scenarios. To illustrate concretely the optimization process, an instance is given in the last.

The common method for producing graphene, the oxidation and reduction method, is not green due to application of corrosive oxidants and reductants, and the obtained graphene is rich in surface defects. Here, we show a novel edge-decoration strategy for the facile exfoliation of graphene layers from graphite. By grafting methyl isopropyl ketone (MIBK) onto the edges of graphite via the aldol condensation reaction, the dense graphene layers become loose, facilitating the exfoliation process and promoting largely the graphene yield from 1.6 to 10.9 wt %. The edge-decoration strategy produces graphene with 5–10 layers and few surface defects. Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and activation experiments prove that the edges of graphite reacted with MIBK via C═O as the active site, causing the grafting of MIBK. We anticipate that the edge-decoration strategy will show great potential in the large-scale production of graphene due to its high efficiency and greenness.

Real-world data streams often exhibit long-tailed distributions with heavy class imbalance, posing great challenges for data stream classification, especially in the case of label scarcity and concept drift. Several active learning methods have been proposed to address this problem by selecting the most valuable instances for labeling. However, existing methods often struggle to dynamically identify the most valuable instances that truly represent the current concept while still requiring a large label budget. In this work, we propose a new algorithm, LEPID, to combine dynamic micro-cluster concept modeling and local entropy modeling to select current important concepts and prototypes. Specifically, we give greater weight to concept drift prototypes and minority prototypes to focus more on those regions that represent current concepts. We use a local entropy strategy based on micro-clusters to select the most valuable instances for labeling and reduce the label budget. Extensive experiments on real-world and synthetic imbalanced datasets show that, compared to state-of-the-art algorithms, our method can naturally adapt to concept drift and dynamically capture the current and most valuable prototypes to achieve better results even in the case of label scarcity. [ABSTRACT FROM AUTHOR]

Investigation on asymmetric hydrogenation of olefins is of great importance in both pharmaceutical molecule synthesis and chemical industry due to the high demand for enantiopure compounds. The established methods often require geometrically pure olefins. The enantioconvergent reaction provided the possibility to access a single stereoisomer via hydrogenation of E/Z-olefin mixtures; however, a polar functional group next to the carbon–carbon double bond was usually necessary. Here, we reported a cobalt-catalyzed enantioconvergent hydrogenation of readily available minimally functionalized E/Z-olefin mixtures. This strategy shows good functional group tolerance and provides an alternative means to enantioconvergent transformation. The preliminary mechanistic studies indicated that cobalt-catalyzed isomerization was the key to achieve the convergent transformation.

A manganese-catalyzed highly site- and enantioselective benzylic C–H azidation of indolines has been described. The practical method is applicable for azidation of a tertiary benzylic C–H bond with good functional group tolerance, allowing facile access to structurally diverse tertiary azide-containing indolines in high efficiency with excellent site-, chemo-, and enantioselectivity. The generality of the method was further demonstrated by site- and enantioselective azidation of the secondary benzylic C–H bond for a range of secondary azide-containing indolines. The benzylic C–H azidation method allows to straightforwardly and enantioselectively install a variety of nitrogen-based functional groups and diverse bioactive molecules at the C3position of indoline frameworks through post-azidation manipulations. Gram-scale synthesis was also demonstrated, further highlighting the synthetic potential of the method. Mechanistic studies by combined experiments and computations elucidated the reaction mechanism and origins of stereoselectivity.

To investigate the correlation between the pollutant removal efficiency of the modified anaerobic/ anoxic/oxic (A2/O) activated sludge biofilm coupling process at low temperature and sludge characteristics, experimental studies were carried out. The study used the A2/O process coupling with biofilm, and the biofilm carrier was placed in the reactor, and the test temperature was controlled at 13°C ± 1°C. Through 180 d of operation, the average removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH4+–N), total nitrogen (TN), total phosphorus (TP) were 86.37%, 92.09%, 74.85%, and 92.76%. The modified A2/O activated sludge-biofilm coupling process could operate stably for 180 d under low temperature condition and had excellent treatment performance. The results of the study of the sludge characteristics of the system showed that the values of extracellular polymeric substances (EPS) content between compartments differed little for activated sludge and significantly for biofilm. Dehydrogenase activity values (DHA) remained similar along the course, but the activated sludge in the system had higher dehydrogenase activity. The research results of nitrification and denitrification rate of each of compartments showed that: O2 was the leading site where nitrification taken place, but the activated sludge in the O1 compartment had a more significant absorption capacity for dissolved oxygen (DO) than O2, the higher nitrification rate in the O1 compartment resulted in a higher NH4+–N removal rate in the O1 compartment.

Graphical abstract:

ABSTRACTCerebral ischemia-reperfusion injury (CIRI) mostly occurs in the treatment stage of ischemic diseases and aggravate brain tissue damage. Although studies have demonstrated that miR-489-3p is closely related to CIRI, the effects of miR-489-3p on neural function in CIRI have not been directly studied. The transient middle cerebral artery occlusion (tMCAO) model was established by suture method, and the corresponding plasmids that interfered with the expression of miR-489-3p or Sirtuin1 (SIRT1) were injected into the model mice, and the behavioral changes of the mice were observed. Then the concentration of serum neuronal injury markers and oxidative stress indices were examined. Next, the pathological conditions, neuronal loss and apoptosis of brain tissue were observed by hematoxylin-eosin staining, Nissl staining, and Transferase-mediated deoxyuridine triphosphate-biotin nick end labeling staining. Finally, the hemoglobin content and cerebral edema in the mouse brain were determined. In addition, the expression levels of miR-489-3p and SIRT1 were detected by reverse transcription quantitative polymerase chain reaction or Western blot, and the targeting relationship between miR-489-3p and SIRT1 was verified by bioinformatics analysis and luciferase reporter assay. The experimental results found that in tMCAO mice, miR-489-3p in brain tissue was up-regulated and SIRT1 was down-regulated. Down-regulating miR-489-3p or up-regulating SIRT1 ameliorated behavioral dysfunction, neuronal damage and apoptosis, oxidative stress and brain histopathology. miR-489-3p targeted the regulation of SIRT1 expression, and down-regulating SIRT1 can reverse the protective effect of silenced miR-489-3p on brain injury. Taken together, by targeting SIRT1, elevated miR-489-3p aggravates CIRI-induced neuronal apoptosis and oxidative stress.

In this paper, a two-stage expectation stability controller was proposed for driving stability of four wheel independent drive electric vehicles. The proposed controller has three levels. There were three steps to the stability control of the vehicle. First, the three-dimensional state portraits were drawn based on the 14DOFs vehicle model and used the stemequation to find two-stage expectation. The surface was derived from the analysis of the tire-road adhesion divides the portraits into safe areas and unsafe areas. Second, the stability controller with sliding mode algorithm was designed. When the state parameter is in the unsafe areas, the safe boundary surface is taken as the first-stage expectation; after the system enters the safe areas, the stemis taken as the second-stage expectation. Then the fuzzy algorithm is applied to distribute the control demand of yaw moment to generate the torques of each in-wheel motor. Finally, simulation verification is performed in Simulink-CarSim co-simulation environment. The simulation results show that the designed control strategy can improve the lateral stability while the loss of longitudinal speed is within 3.25%.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by persistent inflammation of the colon and disrupted intestinal function. Ramulus mori(Sangzhi) alkaloids (SZ-A), derived from twigs of mulberry, were approved by the National Medical Products Administration in 2020 for treating type 2 diabetes mellitus. Accumulated evidence has confirmed that SZ-A also alleviates non-alcoholic fatty liver disease and ameliorates inflammation, indicating its potential to address inflammation in UC. However, the treatment of UC faces challenges due to low drug delivery efficiency and short retention time. To overcome these challenges, an injectable and adherent in-situ thermo-sensitive hydrogel containing SZ-A was developed for rectal drug delivery, utilizing the thermo-sensitive polymers Poloxamer 407 and 188. The thermo-sensitive hydrogel system was designed with a moderate gelation temperature of 32 ± 0.5 °C, a short gelation time of 64 s, a pH range of 7–10, high moisturizing capability exceeding 90%, and moderate mechanical strength of 4–5 s. In a rat model with UC, the in situthermo-sensitive hydrogel significantly extended the retention time at the colonic site and enabled sustained release after rectal administration. Symptoms of UC were markedly reduced following rectal administration of SZ-A thermo-sensitive hydrogel. Furthermore, the release of inflammatory factors, such as interleukin-1β (IL-1β), IL-6, IL-18, tumor necrosis factor-α (TNF-α), and transforming growth factor-β1 (TGF-β1), significantly decreased in the SZ-A thermo-sensitive hydrogel group. The integrity of the colonic mucosal barrier was significantly enhanced following the application of SZ-A thermo-sensitive hydrogel. In conclusion, rectal administration of SZ-A in situthermo-sensitive hydrogel effectively alleviated UC symptoms, inhibited the secretion of inflammatory factors, and promoted the repair of the colonic mucosal barrier. This approach holds promise as a potential treatment for UC.

This article presented a high-efficiency push–pull resonant converter solution for auxiliary power supply in 70-kV isolated applications. This power supply consists of a two-stage structure with a resonant push–pull inverter and a buck regulator. A series resonance is introduced in the inverter with its operation and parameter design to achieve high-efficiency voltage isolation. A buck converter with feedforward control is presented with the small-signal model and controller design to regulate the output voltage. Besides, the transformer is another challenge as a crucial part of the voltage isolation. Specifically, the optimization design of toroidal core and sector windings is presented, including the analysis of isolation, loss analysis, and leakage inductance. This article presents comprehensive converter and transformer models, describing the proposed power supply’s design process. Furthermore, a case study is demonstrated under 70-kV isolation with 36–84 V input and 48-V output. A prototype of a 200-W, 1.4-L isolated power supply has been built to demonstrate the design model’s validity and process. Results convincingly indicate that the proposed converter has the highest efficiency of 93.1% and can maintain the 70-kV isolation voltage with good regulation performance.

In this paper, the crystallization behavior of a novel poly(monothiocarbonate), poly(trimethylene monothiocarbonate) (PTMMTC), was investigated and compared with its polycarbonate analogue, poly(trimethylene carbonate) (PTMC). It is found that PTMMTC exhibits strong crystallizability, while unstretched PTMC is amorphous. DSC and DMA results reveal that PTMMTC possesses higher glass transition temperature (Tg) and β-transition temperature (Tβ) than PTMC. Simulation based on density functional theory (DFT) shows that, the bond angle of C-S-C is evidently smaller than that of C-O-C, and thus a larger dipole moment. This leads to the stronger intermolecular interaction and more rigid chain conformation in PTMMTC, which is the origin of sulfur-substitution enhanced crystallization. The crystal structure of PTMMTC was preliminarily determined for the first time. PTMMTC has an orthorhombic crystal structure with a planar zig-zagchain conformation. The parameters of unit cell are a = 10.74 Å, b = 4.79 Å, and c(fiber axis) = 7.74 Å.

Innovative precise clinical approaches to protect humans from the alarming global growth of chronic disease epidemics, such as metabolic syndrome (MetS), are urgently needed. Here, we introduce protein hydrogels developed through the self-assembly of flavonoids and protein amyloid fibrils as a possible approach to mitigate obesity. After oral administration of the hydrogels, high-fat diet (HFD)-induced obesity was significantly prevented in mice, accompanied by downregulation of lipogenesis and pro-inflammatory genes in the liver and adipose tissue and upregulation of lipid metabolism genes. Additionally, gut microbiota dysbiosis caused by HFD-induced obesity was markedly ameliorated. Overexpression of the host intestinal lipid absorption genes CD36and NFIL3decreased significantly, while the inhibited expression of the gene encoding the tight junction protein Claudin-1was reversed. Furthermore, transplantation of the gut microbiota educated by the hydrogels to germ-free mice showed a substantial prevention effect on HFD-induced obesity, accompanied by a distinct microbiota structure that resisted HFD-induced divergence in microbiota structure. The flavonoid–amyloid fibril hydrogels inhibited the core molecular links between gut microbes and host intestinal lipid absorption, enhanced intestinal barrier function and reduced the abundance of bacterial taxa generating pro-inflammatory products, providing a general concept to design edible biomaterials for obesity prevention by targeting host–microbiota crosstalk.

As the frontier in heterogeneous catalyst, a monomer and positively charged active sites in the single-atom catalyst (SAC), anchored by high electronegative N, O, S, P, etc., atoms, may not be active for the multispecies (O2, substrates, intermediates, solvent etc.) involved liquid-phase aerobic oxidation. Here, with catalytic, aerobic oxidation of 5-hydroxymethylfurfural as an example, Pt SAC (Pt1-N4) was synthesized and tested first. With commercial Pt/C (Pt loading of 5 wt %) as a benchmark, 2,5-furandicarboxylic acid (FDCA) yield of 97.6% was obtained. Pt SAC (0.56 wt %) gave a much lower FDCA yield (28.8%). By changing the coordination atoms from highly electronegative N to low electronegative Co atoms, the prepared Pt single-atom alloy (SAA, Pt1-Co3) catalyst with ultralow Pt loading (0.06 wt %) gave a much high FDCA yield (99.6%). Density functional theory (DFT) calculations indicated that positively charged Pt sites (+0.712e) in Pt1-N4almost lost the capability for oxygen adsorption and activation, as well as the adsorption for the key intermediate. In Pt1-Co3SAA, the central negatively charged Pt atom (−0.446e) facilitated the adsorption of the key intermediate; meanwhile, the nearby Co atoms around the Pt atom constituted the O2-preferred adsorption/activation sites. This work shows the difference between the SAC with NPs and the SAA during liquid-phase oxidation of HMF and gives a useful guide in the future single-atom catalyst design in other related reactions.

An asymmetric 1,6-conjugate addition to presynthesized δ-aryl-δ-cyano-disubstituted para-quinone methides through bifunctional phosphonium-amide-promoted ion-pair catalysis for acyclic all-carbon quaternary stereocenter construction has been described. Both acyclic and cyclic 1,3-dicarbonyls participate in the asymmetric alkylation reaction, furnishing a wide array of diarylmethanes bearing a single acyclic quaternary carbon stereocenter or vicinal cyclic and acyclic quaternary carbon stereocenters with high efficiency and excellent stereoselectivity. Computational studies elucidate the origin of the enantioselectivity.

The rapid progress in microelectronic devices has brought growing focus on fast charging-discharging capacitors utilizing dielectric energy storage films. However, the energy density of these dielectric films remains a critical limitation due to the inherent negative correlation between their maximum polarization (Pmax) and breakdown strength (Eb). This study demonstrates enhanced energy storage performance in multilayer films featuring an ultra-thin layer structure. The introduction of a greater number of heterogeneous interfaces improves Eb, while lattice distortion and phase transitions, facilitated by diffusion and strain at interfaces, contribute significantly to the enhancement of Pmax. Remarkably, an energy density of 65.8 J/cm3with an efficiency of 72.3% was achieved in a 6.7 nm-per-layer BiFeO3/SrTiO3multilayer configuration, surpassing the performance of most multilayer films composed of simple constituents. This ultra-thin multilayer structure, which simultaneously promoted Pmaxand Eb, provides a promising avenue for the development of high-performance dielectric materials.

Ulcerative colitis (UC) is a common progressive inflammatory disease whose incidence has increased rapidly in recent years, and can develop into colorectal cancer in severe cases. There are currently no adequate or effective treatments for UC due to the fact that some patients have found suboptimal results after repeated administration, while others have experienced adverse effects. With the rapid development of nanotechnology, developing innovative colon-targeting platforms is essential to improving efficacy, reducing side effects, and improving patient compliance. In this review, we summarize the pathophysiological characteristics of UC and the most recent status of numerous nanodrug delivery systems based on different targeting mechanisms in treating UC. Oral, intravenous, and rectal drug delivery nanoparticles targeting the colon are discussed, which can provide ideas for the design of colon-targeting nanoparticles for the treatment of colon diseases, especially for the treatment of UC. Last but not least, we provide a glimpse into the future of colon-targeted delivery systems, as well as future advancements in the field.

Pig production contributes considerably to land use and greenhouse gas (GHG) and reactive nitrogen (Nr) emissions. Land use strategies were widely proposed, but the spillover effects on biological flow are rarely explored. Here, we simultaneously assessed the carbon (C), nitrogen (N), and cropland footprints of China’s pig production at the provincial scale in 2017. The environmental impacts of land use strategies were further evaluated. Results show that one kg live-weight pig production generated an average of 1.9 kg CO2-equiv and 59 g Nr emissions, occupying 3.5 m2cropland, with large regional variations. A large reduction in GHG (58–64%) and Nr (12–14%) losses and occupied cropland (10–11%) could be achieved simultaneously if combined strategies of intensive crop production, improved feed-protein utilization efficiency, and feeding co-products were implemented. However, adopting a single strategy may have environmental side-effects. Reallocating cropland that pigs used for feed to plant food alternatives would enhance human-edible energy (3–20 times) and protein delivery (1–5 times) and reduce C and N footprints, except for rice and vegetables. Reallocating cropland to beef and milk production would decrease energy and protein supply. Therefore, a proper combination of land use strategies is essential to alleviate land use changes and nutrient emissions without sacrificing food supply.

The types and concentration of mercury in flue gas of nine coal-fired units were measured by OH method and the mercury content in desulfuration wastewater, slag, fly ash and gypsum were also measured. The influences of conventional pollutant removal facilities such as SCR denitration facility, dust removal facility, and wet flue gas desulfurization facilities on mercury type and concentration were studied. The results indicate that mercury emission type is mostly gaseous mercury and mercury emission in nine units all meets the standard requirement. SCR denitrification facilities have a great effect on mercury type, promoting oxidation of elemental mercury into oxidized mercury which is easily removed by downstream dust removal facilities and wet desulfurization facilities. Particulate mercury is synergistically removed in dust removal facilities, with mercury removal ratio between 13.5% and 80.6% which depends on particulate mercury proportion. The oxidized mercury is synergistically removed in wet desulfurization facilities, with mercury removal ratio between 9.0% and 72.9%. Mercury is transferred from coal to fly ash and desulfuration gypsum, and mercury stability in the solid by-products needs to be studied.

The molten‐salt method was used to synthesize CaBi2Ta2O9(CBTa) powder, and the influence of temperature on the structure and micromorphology of products was investigated using X‐ray diffraction and the scanning and transmission electron microscope. The results showed that highly crystalline CBTa nanoplates exhibit single orthorhombic symmetry and could be obtained in the temperature range of 850–900 °C. Among which, the nanoplates prepared at 900 °C have optimal properties (average grain size of 1.7 μm and uniform size distribution). Above 900 °C, various CaO–Ta2O5binary compounds, Bi2O3,and BiTaO4formed due to the decomposition of CBTa and subsequent reactions of decomposition products, transforming plate‐like grains to cuboid nano‐particles with a small amount of prismatic grains. Possible reaction mechanisms at different synthesizing temperature were proposed. This work provides a method for the preparation of template grains to synthesize textured CaBi2Ta2O9high‐temperature piezoelectric ceramics by the template grain growth method.

Selective separation of phenanthrene (PHE) from aromatic isomer mixtures is a big challenge in industry. In this work, a light-responsive water-soluble azobenzene-based macrocycle 1is synthesized and an aqueous solution of E,E-1is employed to separate PHE from anthracene via a solid–liquid extraction method under ambient conditions. After five extraction cycles, the average purity for PHE is about 91.1% and macrocycle 1can be reused at least five times without obvious reduction of separation performance for PHE. This work not only comprises a new and clean way to separate PHE by taking advantage of a macrocyclic host but also promotes the application of host–guest chemistry.

To evaluate the clinical efficacy of infusion of gemcitabine (GEM) and fluorouracil (5-FU)through the celiac artery and superior mesenteric artery in the treatment of pancreatic carcinoma (PC).

Meloidogyne incognitais a wide-spread and damaging pathogen of many important crops in the southern United States, and most sorghum genotypes allow significant levels of reproduction by the nematode. A series of greenhouse evaluations were conducted to determine whether a quantitative trait locus (QTL) that imparts a high level of resistance to Meloidogyne incognitain sorghum can effectively be transferred into diverse sorghum genotypes using marker assisted selection. Using marker-assisted selection, the resistance QTL, QTL-Sb.RKN.3.1, from ‘Honey Drip’ sorghum was crossed into five different sorghum backgrounds that included forage, sweet, and grain sorghum until the BC1F6generation. Repeated greenhouse experiments documented that the recurrent parent genotypes were all susceptible to M. incognitaand statistically similar to each other. In contrast, the BC1F6genotypes were all highly resistant and similar to each other and similar to the resistant standard, ‘Honey Drip’. These results suggest that this resistance QTL could be introgressed using marker assisted selection into many sorghum genotypes and confer a high level of resistance to M. incognita. Thus, this QTL and its associated markers will be useful for sorghum breeding programs to incorporate M. incognitaresistance into their sorghum lines.

A hexacationic cage 36+was synthesized via hydrazone condensation in aqueous acid. Cage 36+bears three biscationic arms, each of which contains four relatively acidic protons, including one NH and three CH protons. These hydrogen bond donors, as well as its intrinsic cationic nature, enable cage 36+to encapsulate two anions concurrently within its cavity. The axial asymmetrical nature of the biscationic arms allow the cage to recognize two different anions in a selective manner, to encompass bound heteroanion dimers, such as Cl–·NO3–and Cl–·Br–. Single crystal X-ray diffraction analyses reveal that in the solid state the two anions are constrained in ultraclose proximity within the cage; e.g., the Cl–···Cl–and Cl–···Br–distances are 3.2 and 2.9 Å, respectively, which are shorter than the sum of their van der Waals radii. Evidence consistent with the sequential binding of two identical or disparate anions in CD3CN is also presented.

The large influx of antibiotics in the environment may pose a threat to humans. Therefore, the fate of antibiotics in the environment has attracted a great deal of attention. In this work, the degradation of oxytetracycline (OTC), a type of tetracycline antibiotic, by UV-activated peroxydisulfate (PDS) advanced oxidation process was investigated. The results showed that OTC could be efficiently degraded by UV/PDS, with the degradation process following the pseudo-first-order kinetics equation. The degradation rate was dependent on the initial concentration of PDS. Neither acidic nor alkaline conditions facilitated the degradation of OTC. The existence of Cl–promoted the degradation of OTC, whereas other inorganic ions (NO3–, CO32–, and HCO3–) slightly inhibited the degradation of OTC. Meanwhile, humic acid and fulvic acid strongly inhibited the removal of OTC. In a natural water matrix, OTC degradation was slowed down compared with that in ultrapure water. Ultra- high-performance liquid chromatography time-of-flight mass spectrometry yielded five products of OTC degradation. The degradation pathways were primarily decarbonylation, dehydration, hydroxylation, and secondary alcohol oxidation.

We report a dual-interfacial engineering approach that uses a sub-20 nm polycrystalline MOF-74 shell as a transition phase to engineer the MOF–polymer interface. The application of a shell MOF layer divides the original single interface problem into two interfaces: MOF–MOF and MOF–polymer, which can be individually addressed. The greater external surface area created by the uneven MOF-74 shell containing high-density open metal sites allows the MOF to interact with 300% polymer at the interface compared to traditional MOF, thereby ensuring good interfacial compatibility. When applied on UiO-66-NH2, its respective mixed-matrix membranes exhibit a simultaneous increase of CO2/CH4separation selectivity and CO2permeability with increasing MOF loading, implying a defect-free interface. When applied on MOF-801, the mixed-matrix membranes exhibit an ethylene/ethane separation selectivity up to 5.91, a drastic 76% increase compared to that of the neat polymer owing to a “gas focusing” mechanism promoted by the preferred pore orientation in the MOF-74 layer. This represents one of the most selective ethylene/ethane separation membranes reported to date.