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Common-mode chokes (CMCs) are essential components of electromagnetic interference (EMI) filters. Obtaining precise common-mode (CM) and differential-mode (DM) impedance information of CMCs facilitates their performance evaluation and behavioral modeling, ultimately contributing to optimal EMI filter design. Among existing impedance extraction approaches, measurement methods are the most straightforward, not requiring CMC's detailed geometry and material properties. These methods typically use an impedance analyzer (IA) or vector network analyzer (VNA) with specific fixture adapters for measurements. However, these adapters introduce parasitics, which can affect measurement accuracy, particularly at high frequencies. Some solutions have been proposed but limited to single-phase CMCs. This article presents two impedance measurement methods for three-phase CMCs: single-port circuit de-embedding (SCD) and three-port network calibration (TNC). Both methods consider the parasitics of fixture adapters and provide unique solutions for accurate broadband measurements for the CM and DM impedances of three-phase CMCs. The SCD method has good versatility as it can be implemented using either an IA or VNA; however, it requires fixture adapter details for the de-embedding process. Conversely, the TNC method does not need these details but can only be implemented using an IA. Both methods are validated experimentally with good accuracy from 150 kHz to 120 MHz.

The purpose of this study was to explore the relationship between the evolution of key Salviaenzyme genes and metabolite biological activity on mitochondrial quality control. Metabolomics and transcriptomics were performed to detect the metabolites of Salviaand 76AH1(CYP450) genes and a maximum likelihood tree for Salviawas established. Additionally, the protein properties of 76AH were analyzed and the metabolite, as well as mitochondrial quality control, targets were downloaded from the TCMSP, BATMAN, and GeneCards databases and analyzed. Molecular docking of PINK1 with cryptotanshinone and tanshinone IIA was assessed and a molecular binding area was identified. Moreover, the specific types of Salviasecondary metabolites were accurately identified and quantified with nearly all AH1 genes having been sequenced. This study begins to elucidate the relationship between species evolution and biological activity. Specifically, the structural analysis demonstrates that cryptotanshinone and tanshinone IIA exhibit strong pharmacological activity in mitochondrial quality control.

Oxide-dispersion-strengthened (ODS) steels are candidate materials for application in advanced nuclear reactors. In this study, the low-cycle fatigue performances of 13Cr-ODS ferritic steel pipes were investigated at 600, 700, and 800 °C. Cyclic softening was observed at high strain amplitudes with an increase in the number of fatigue cycles. However, cyclic hardening appeared first, and then cyclic softening occurred at a low strain amplitude with the increase in the number of fatigue cycles. By comparing the cyclic stress–strain curves and the monotonic stress–strain curves, it was found that cyclic softening occurred regardless of the strain amplitude. The Coffin–Manson and Basquin equations were used to predict the fatigue of the pipes. Microstructure analysis indicated that cyclic softening was induced by the dynamic recovery and recrystallization, which reduced the number of low-angle grain boundaries in the deformed grains by promoting dislocation annihilation and reorganization. A complex multi-layer core–shell structure with a large size (∼500 nm) was observed.

A novel resonant tri-coil transducer is proposed to induce thermoacoustic (TA) signals for detecting rail internal defects. It consists of a ferrite plate-backed tri-coil and its associated circuits, a shielding layer, and a three-dimensional printed enclosure for supporting and securing. General TA detection theory is illustrated to understand how to detect rail internal defects. For achieving electromagnetic (EM) field shaping and focusing, the physical structure of the proposed transducer is optimized. It reduces backward EM fields and interference. Then, an equivalent circuit model between the proposed transducer and the rail is constructed to analyze optimal power transfer efficiency as a function of distance and frequency. To validate the design concept, the proposed transducer is fabricated for inducing TA signals, and experiments are performed. Several engineered rail specimens (UIC-60E) with different types of defects are prepared. The induced TA waves are found to be compressional. With selected features, a support vector machine algorithm-based multinomial classifier model is trained and employed for intelligent processing. Then, the proposed transducer is integrated into the self-designed automatic rail monitoring system. Experimental results show that the self-designed system can achieve an accuracy rate of 96.4%, successfully identifying defects in defect classification. The proposed transducer has low cost in fabrication and maintenance, focused magnetic fields with a large lift-off distance and enhanced acoustic wave intensity. Compared to earlier version of the system, the spacing between the transmitter and the rail has been further increased.

With the Frontier supercomputer ranked first on the Top500 list, it marks the era of exascale computing power for supercomputers, employing the compute nodes with double-precision floating-point performance exceeding 100 TFLOPS. As the basic computing unit of supercomputers, the efficiency of compute nodes significantly impacts the processing efficiency of application workloads in different domains, such as scientific computing and artificial intelligence. This article systematically analyzes the architectures and key technologies of major supercomputers already built or soon to be constructed in the world, and summarizes the development trends of 100 TFLOPS compute nodes technology. This paper provides some valuable insights on how to address the challenges imposed by future 10-exascale and even zettascale supercomputers, which include improving energy efficiency, optimizing memory access, utilizing chiplet interconnection, and employing advanced packaging technology. This will help scholars in related fields to further think about future research directions, and help industrial employees to construct more practical and efficient compute nodes for the future supercomputers.

It is of imperative interests for regional transmission organizations (RTOs) to effectively extract actual load profiles at transmission nodes with significant behind-the-meter solar generation, which remains a gap in the existing technology paradigm. This paper proposes an explicit yet efficient linear estimator to disaggregate actual load profiles at transmission buses with significant behind-the-meter (BTM) solar generations. The proposed estimator is based on disaggregating (i.e., extracting) at locations close to transmission buses under consideration. To overcome the lack of ground truth and validate the performance of the proposed algorithms, we first propose semi-supervised mechanisms with parameter tuning as well as unsupervised clustering and leverage the unique characteristics of zero-crossing points in BTM solar peaking behaviors, which we refer to as Zone-to-Node (Z2N) methods. Next, we further propose a bi-level Node-to-Node (N2N) framework that improves the overall disaggregation performances compared to Z2N. Numerical results are presented using real-world data at PJM Interconnection.

Reasonable grid line engineering asset management is an important means for power companies to improve economic efficiency under the new electricity reform situation. Based on the whole-life-cycle theory, this paper puts into use the decommissioning of the whole process of cost perspective and analyses the line project construction to decommissioning and scrapping of the whole process of the cost. Through the calculation of the whole life cycle of the smallest annual cost, to determine the line economic life, the authors constructed the whole life cycle of a grid line project economic cost framework and put forward the best decommissioning time of a grid line model – that is, the economic life model. A case study was conducted based on a project example from a certain power grid company in China. The research results of this paper can be used to reduce the economic cost of operation and maintenance of power grid enterprises, improve the efficiency of input and output and provide reference suggestions for optimising the management of line engineering and other power assets of power grid companies.

Rail crack detection is an essential role in the safety assurance of railway transportation. However, conventional crack detection methodologies suffer from the interference of pronounced wheel–rail rolling noise (WRRN), thereby frequently undermining detection precision. Aiming to address this issue, a novel rail crack detection method based on electromagnetic acoustic emission (EMAE) technology is presented in this article. The proposed method leverages optimal local mean decompose (OLMD) signal reconstruction algorithm, alongside a novel detection index, called cepstral information coefficient (CIC). Designed to obviate the strong WRRN interference, the OLMD algorithm has been optimized via the empirical optimal envelope (EOE), amending inaccuracies in both mean and envelope functions. Subsequently, the original signal is reconstructed by linear superposition of the first product function (PF) component from the OLMD algorithm, enhancing the information pertaining to crack characteristics. The emergent detection index CIC derives from the fusion of the primary dimensions of the gammatone cepstral coefficients (GTCCs) employing a linear transformation matrix, demonstrating exceptional proficiency in crack detection. Finally, the effectiveness and advantages of the proposed method have been demonstrated experimentally.

The current collector is a key component of most light rail transit (LRT) trains. It draws electric power from the catenary or the power rail for each moving train. Due to wear, tear, and harsh operating environments, the current collector will malfunction, which can lead to unexpected power interruptions for the train and directly affect service reliability. This article presents an inductive coupling method for current collector health monitoring of LRT trains powered by the three-phase ac power rail. The monitoring system developed using the proposed method can be easily fitted on a train so that it doubles up as a train-borne health monitoring system (TBHMS) during revenue hours. The TBHMS monitors the electrical contact quality (ECQ) between the current collector shoe (CCS) and the power rail in a noncontact and safe manner. By doing so, it eliminates the need of inspection during engineering hours, which is both labor-intensive and time-consuming. The current collector of such trains comprises a current collector assembly that holds the CCSs. Two performance indexes, the contact quality index and the contact loss index, are defined to quantify the health conditions of CCS and CCA, respectively.

Power grid construction projects are crucial for national industrial development. To improve the investment efficiency (IE) of substation engineering construction, this study determines the influencing factors of the input and output of substation construction projects through the entropy weight method (EWM) principle and constructs the evaluation model of IE of substation engineering construction by using data envelopment analysis (DEA) theory. Considering substation projects of a power grid company as an example, this article evaluates and compares the investment economy of one-time and phased construction to maximise the economic efficiency of substation project construction. Hence, our study provides scientific reference for investment decision-making involving substation projects and promotes collaborative planning of various regions, projects, and assets under the construction of substation projects. The results show that the IE of phased substation construction projects is higher than that of one-time construction. This effectively improves the IE of power grid companies.

As time goes by, the rails of high-speed trains are subject to long-term extrusion and natural factors, and defects will gradually appear. Therefore, early detection of these defects is extremely important for the maintenance or replacement of rails. In this article, a set of rail internal crack detection system is proposed and developed, which can be easily and conveniently deployed for daily maintenance of the rails. To improve the detection speed, thermoacoustic technology is utilized and researched. For rail head internal defects, thermoacoustic induced by a coil antenna is used for detection. For rail foot internal defects and bottom corrosion, laser-induced thermoacoustic is used for detection. First, the thermoacoustic technique is analyzed and applied to rail defect detection. Next, it is used to analyze and confirm the effectiveness of the coil antenna and laser-based thermoacoustic detection technology through laboratory experiments and signals analysis. To validate the proposed system’s design concept, a prototype of the detection trolley is constructed that generates thermoacoustic signals and conducts experiments accordingly. In the field trial, an intelligent processing approach is employed using a conventional method of outlier analysis, trained with specific features. The test results demonstrate the effective detection of rail internal defects by the proposed system.

Soybean Phytophthora root rot (PRR) caused by Phytophthora sojaeis one of the most devastating diseases of soybean worldwide. This study was conducted to develop new effective biocontrol agents for the control of the disease and explore the action mechanism.Eleven antagonistic bacterial strains against P. sojaewere isolated from the soybean field soil samples, and among the strains, BS-4 not only had the strongest inhibitory activity against P. sojae, but also had good inhibition to other four species of oomycetes in Phytophthoraand eight fungal pathogens. Based on 16S rDNA sequence analysis and the physiological and biochemical properties, the strain BS-4 was identified as Bacillus altitudinis. Strain BS-4 culture filtrate had significant inhibitory effects on the pathogens, and the inhibition rates were stronger than those in the dual culture. BS-4 filtrate kept a high bioactivity to P. sojaeat a high temperature, even at 121℃, and in the pH range of 5 to 12. The germination of zoospores and the formation of sexual organs were seriously affected by BS-4 filtrate. Furthermore, detached leaf assays and greenhouse experiments showed that BS-4 suspension and culture filtrate all had good disease control efficacy, and in the field experiment, BS-4 suspension reduced the disease index and increased the biomass of soybean shoots and roots, significantly (P< 0.05), with control effect of 75.29% on PRR. It is suggested that B. altitudinisstrain BS-4 is a novel potential biocontrol agent to control PRR, and will have a broad application prospect in PRR biocontrol.

In the physical design of integrated circuits, clock tree synthesis (CTS) plays a crucial role in terms of timing closure and overall design convergence. The existing clock tree (CT) optimization methods usually prefer to balance both clock edges, and the key insight of this article is that the clock work edge does not need to keep balance with another nonwork edge for the widely employed single-edge triggered circuits. This motivates us to achieve CT optimization by improving the performance of the work edge while sacrificing the performance of another edge. To this end, complementary asymmetrical uniform transistor sizing (CAUTS) methodology is proposed, which enables us to: 1) improve those conflicted metrics in systematic ways, including clock latency, power, and so on and 2) perform CTS optimization without any clock buffer insertion and clock routing adjustment and thus without area penalty. Experimental results based on the first-generation FinFET technology with six benchmark circuits and four industry intellectual properties (IPs) demonstrate that: 1) the clock latency is reduced by 5.9%–19.8% at each corner for all designs; 2) the clock power is reduced by 2.45%–15.12% at each corner for all designs; 3) setup timing is improved for all designs, and the total negative slack (TNS) of setup timing for unclean corners can be reduced by 10.9%–73.6%; and (4) hold timing is improved for all designs, and the TNS of hold timing can be reduced by 5.2%–19.8% for four industry IPs.

Thesium chinenseis an important and commonly used traditional Chinese medicine. The aim of this study is to obtain more bioinformatics from Thesium chinenseand to conduct a more comprehensive and in-depth analysis of Santalaceae's phylogeny. This study sequenced the chloroplast genome of Thesium chinenseand performed bioinformatics analysis on its key genes to reconstruct the Santalaceae phylogenetic tree. The genes of traditional Chinese medicine often affect the generation and accumulation of metabolic products. The different genes in the chloroplast genome of Thesium chinensehave different biological characteristics. The phylogenetic system of Santalaceae and its related families differs significantly from classical classification. This study has laid a solid foundation for the better application and identification of Thesium chinense.

The increasing penetration of solar generation into power grids has promoted the need for accurate and reliable short-term solar irradiance forecasting. Existing methods utilizing advanced deep learning architectures have shown advanced performance compared to conventional time-series analytical techniques but in general encountered shortcomings in modeling spatial correlations among neighboring solar generation sites, exploring the similarity of long-term, time-varying patterns, and alleviating overfitting issues in convolutional and recurrent neural networks, such as the popular Long Short-term Memory (LSTM). To effectively but yet reliably tackle these challenges in the existing literature, this article proposes a spatio-temporal framework consisting of a multi-branch hybrid Residual network and the Transformer architecture (ResTrans). The proposed framework has been tested on two groups' real-world data containing 17 years-long data from different solar sites in Philadelphia, USA, including 12 and 18 locations, respectively. Compared to other hybrid benchmark architectures, including single-branch ResTrans and multi-branch ResNet-LSTM (ResLSTM), single-branch ResLSTM, and CNN-LSTM, the proposed multi-branch ResTrans achieves the highest forecasting accuracy with an average RMSE of 0.049 (W/m2), an average MAE of 0.031 (W/m2), and an $R^{2}$ coefficient of 97%.

High levels of deoxynivalenol (DON) contamination in foods can raise health risks for enterohepatic diseases. Here we report our investigation into the trichothecenes (DON, 3‐acetyl‐deoxynivalenol, 15‐acetyl‐deoxynivalenol), zearalenone (ZEA) and nivalenol (NIV) showing in the wheats‐processed noodles in Shandong, China (2019–2020). The noodles contamination status of DON in Shandong was closed to that in China in the past 10 years: 4663.9 µg/kg at maximum level, and a range of 57.9–618.8 µg/kg by mean. However, the average levels of DON measured in the noodle samples varied largely by city. Highest levels of DON contamination were found in Binzhou: 709.09 (58.8–3220) µg/kg and Weihai: 684.79 (27.6–3850) µg/kg, respectively. Besides, NIV contamination were averagely 46.99 µg/kg in Binzhou, and ZEA contamination up to 31.4 µg/kg in Weihai, pose an increasing threat of liver/intestine inflammation associated with dietary exposure. The DON contamination status of noodles in Shandong was consistent with our previous investigation in wheats and in recent 10 years in China, that increased health risks for enterohepatic diseases. To understand the contamination situation of DON, ZEA, and NIV in noodles, so as to assess the health risks for enterohepatic diseases caused by mycotoxin in Shandong province.

The single-probe setup (SPS) based on the inductive coupling approach is a promising candidate for in-circuit impedance measurement of an energized electrical system due to its noncontact characteristics and simple configuration. However, the conventional SPS performs the measurement with a frequency-domain measuring instrument via stepped swept-sine excitation. It measures in-circuit impedance at only single frequency at a time while sweeping across frequencies of interest, which is not only inefficient but also not fast enough to capture in-circuit impedance with time-variant characteristics. To overcome these limitations, this article proposes a novel SPS with a time-domain measuring instrument via multisine excitation. The proposed SPS can perform multifrequency simultaneous measurement of in-circuit impedance without direct electrical contact. By combining it with a short-time Fourier transform algorithm, in-circuit impedance with time-variant characteristics can be captured. Experimental case studies validate the capability and accuracy of the proposed SPS.

Differential-mode and common-mode chokes (DMC and CMC) are key components of electromagnetic interference filters. Accurate impedance knowledge of these chokes allows optimal EMI filter design to meet the conducted emission requirements. An impedance analyzer or vector network analyzer with a fixture adapter is commonly adopted for impedance measurement of a passive component. Usually, the non-standard terminals of both DMC and CMC make them incompatible for direct mounting on commercially available fixture adapters. Relying on additional interconnects to the fixture adapters introduce inherent parasitic effects that limit measurement accuracy up to several megahertz. This article proposes a design method of customized fixture adapters which are specifically tailored for impedance measurement of single-phase DMC and CMC. Through a systematic parasitic de-embedding process, the choke impedance can be extracted with excellent accuracy up to 120 MHz.

Phase-structured light beams carrying orbital angular momentum (OAM) have a wide range of applications ranging from particle trapping to optical communication. Many techniques exist to generate and manipulate such beams but most suffer from bulky configurations. In contrast, silicon photonics enables the integration of various functional components on a monolithic platform, providing a way to miniaturize optical systems to chip level. Here, we propose a series of on-chip subwavelength holographic waveguide structures that can convert the in-plane guided modes into desired wavefronts and realize complex free-space functions, including the generation of complex phase-structured light beams, arbitrarily directed vortex beam emission and vortex beam focusing. We use a holographic approach to design subwavelength holographic surface gratings, and demonstrate broadband generation of Laguerre–Gaussian (LG) and linearly polarized (LP) modes. Moreover, by assigning appropriate geometric phase profiles to the spiral phase distribution, the off-chip vortex beam manipulation including arbitrarily directed emission and beam focusing scenarios can be realized. In the experiment, directed vortex beam emission is realized by using a fabricated tilt subwavelength holographic fork grating. The proposed waveguide structures enrich the functionalities of dielectric meta-waveguide structures, which can find potential applications in optical communication, optical trapping, nonlinear interaction and imaging.

A novel compact multiple-input multiple-output (MIMO) antenna is proposed with wideband gain enhancement. It consists of two identical antenna elements spacing about half wavelength. First, a 1-to-2 Y-shaped power divider with wideband anti-phase outputs is designed to feed two modified Vivaldi radiators. The currents on the two radiating surfaces keep the same direction in a wideband to increase radiation without being canceled. Second, the square-ring unit cell is analyzed to form metasurface, placed in the front of the radiator. It can guide the forward electromagnetic (EM) radiation while reducing the backward radiation. Third, a U-shaped slot is etched between the two modified Vivaldi radiators. It is approximated as an effective electrically small dipole radiator. Such arrangement further effectively enhances the radiation performance in the direction of the main lobe and destructively interferes with the sidelobe radiation. These features make the antenna far-field radiation pattern reshaped. Thereby, the gain is improved in a wide bandwidth. Meanwhile, the MIMO antenna diversity performance is analyzed with low mutual coupling. Wideband gain enhancement contributes to improve the detection capability of the frequency modulated continuous wave (FMCW) radar sensor. As a proof of concept, the proposed MIMO antenna prototype is fabricated. The measured impedance bandwidth ranges from 11.5 to 21.3 GHz [59.76% fractional bandwidth (FBW)] with isolation of $\ge 24.92$ dB. The gain is up to 10.6 dBi, the radiation efficiency is 88.01%–90.02%, and the envelope correlation coefficient (ECC) is $\le 0.00122$ . Integrated with the transceiver chip fabricated on the 65 nm CMOS process, the proposed MIMO antenna is applied in the FMCW radar sensor. The test system is built up, and the experiments on different breathing conditions are conducted for different human subjects. The proposed MIMO antenna could reduce measurement error, thereby improving measurement accuracy for human respiratory monitoring.

Rail foot corrosion is an important issue for the electrified railway system. It usually initiates at the bottom of rail foot edges covered by a rail clip and is hardly accessible to conventional online inspection systems. To address this problem, this study combines air-coupled ultrasonic transducer (AUT) and laser-induced ultrasonic guided wave to detect rail foot corrosion. The corrosion sensitivity of the guided wave below 500 kHz is examined considering the impact of the rail clip. The results have shown that $A_{0}$ and $S_{0}$ are the dominant wave modes near the edge of the rail foot. The preferred $A_{0}$ wave is insensitive to allowable rail foot corrosion below 100 kHz. It is neither sensitive above 270 kHz due to wave mode conversion and reduced wave penetration. The optimal frequency is about 200 kHz where the attenuation of the $A_{0}$ wave can reflect the impact of all levels of corrosion even in the presence of a rail clip. Accordingly, an end-to-end deep learning model is employed for corrosion detection based on 200-kHz air-coupled ultrasonic signals. It can automatically extract signal features for corrosion diagnosis as well as differentiate unknown anomalous signals by environmental interference. It is tested with 8122 labeled signal samples collected from field trials and achieves a detection accuracy of 99.5%. All the anomalous signals are also correctly identified.

Ultrahigh frequency (UHF) partial discharge (PD) detection is essential for routine maintenance of gas-insulated switchgear (GIS). Realizing low-noise detection with cost-effectiveness and ease of installation is promising but challenging. This article presents a novel broadband noise-shaping network (BNSN) integrated with a printed monopole antenna (PMA) sensor to realize sufficient noise rejection and good impedance matching. Moreover, by analyzing the equivalent noise circuit and co-designing a high-speed preamplifier circuit with the proposed sensor, the detection sensitivity and anti-interference of the proposed sensor module are improved. The effectiveness and superiority of the proposed sensor are first verified in accordance with IEC 62478, followed by validations using a PD simulator and a real 24-kV GIS. The experimental results demonstrate that the proposed sensor module has the capability to identify different PD types even in noisy environments.

The measurement of water fraction in the oil–water two-phase flow is important for the processing control of oil production. In this article, a coil antenna-based high-sensitivity inductive sensor is proposed to measure the water fraction in the oil–water two-phase flow in real time. It employs a wire-wound coil antenna, an associated signal processing circuit, and a sensor fixture to support and hold them. The change of water fraction in the flow causes the change in equivalent inductance of the coil antenna. By adding external capacitors to the coil antenna, a parallel inductance–capacitance resonant circuit is formed, and it efficiently converts the inductance change to the voltage change, which improves the measurement sensitivity. The specified signal processing circuit picks up the voltage change, realizes the ac/dc signal conversion, and amplifies dc small signals. Then, the measurement theory is analyzed, and the transduction model of coil inductance change to voltage output is given. To verify the proposed inductive sensor, a prototype is fabricated, and a measurement platform is built, in which the generated oil–water flow has a water fraction ranging from 0% to 100%. Experimental results show that the proposed inductive sensor can measure the water fraction in real time with a measurement resolution of 1% and a measurement standard deviation of less than 1.2%.

How to ensure the safety of occupants has become a challenge for protective design of armored vehicles against intensive blast loadings. In this study, for armored vehicles subjected to shallow-buried explosions, an analytical model was established to characterize the dynamic performance of an all-metallic sandwich floorboard attached with a double mass-spring-damping system (mimicking seat and occupant), with the former consisting of a front face, a core and a rear face. For validation, numerical simulations with the method of finite elements (FE) were performed. Good agreement between analytical predictions and numerical results was achieved.The analytical model was then employed to quantify the effects of explosive mass, yield stress of material make, configurational parameters of sandwich panel, spring stiffness, and damping coefficient on dynamic response of the sandwich panel and double mass-spring-damping system. With increasing explosive mass and decreasing yield stress of material make, the peak displacements of rear face, seat and occupant were all found to increase. As core relative density was increased, these peak displacements also increased when the ratio of face thickness to core height was relatively small. Increasing the ratio of face thickness to core height led to increased peak accelerations of seat and occupant. The peak displacement of rear face was insensitive to the increase of either spring stiffness or damping coefficient, while the peak acceleration of occupant increased with increasing spring stiffness. Upon increasing the damping coefficient between the rear face and seat or that between the seat and occupant or both, the peak acceleration of occupant increased. With occupant safety duly considered, the proposed analytical model provides useful guidance for designing high-performance protective structures for armored vehicles subjected to intensive blast loadings.

Developing an effective and selective catalyst for epoxide hydration under low water/epoxide ratios and atmospheric pressure is still a challenge. Through tuning the anion, azolate ILs with different basicities were used in the hydration of epoxides. The results showed that the basicity has a great effect on conversion and selectivity, where [Emim][Triz] exhibited high conversion and selectivity under 1 bar CO2, leading to the yield of 99%. Furthermore, these ionic liquids could be used four times and retain good catalytic activity. Spectroscopic investigations, isotope labeling experiments, and quantum chemical calculations indicated that high yield was derived from synergetic catalysis by an azolate ionic liquid, which was more favorable than the hydration process catalyzed by bromine and organic bases.

We demonstrate a multifunctional optical spectral shaper on a silicon photonic chip. The proposed structure is composed of a tunable microring resonator (MRR) and three tunable Sagnac loop mirrors (SLMs), which can be regarded as a large SLM incorporating an MRR-coupled Fabry–Perot (FP) cavity. To realize flexible tuning, thermo-optically tunable Mach-Zehnder interferometer (MZI) couplers are used to replace conventional directional couplers with fixed coupling coefficients. By controlling the tunable MZI couplers, the proposed structure can be reconfigured as various functional structures including an all-pass MRR with tunable coupling regime, a tunable FP cavity, an SLM incorporating FP cavity, and an MRR-coupled FP cavity. This flexible reconfiguration allows for multifunctional optical spectral shaping including tunable comb filtering, Fano and EIT-like resonances. In particular, the complementary flat-top comb filtering responses can be theoretically obtained in the two ports of this device with same free spectral range (FSR) value, which enable the (de)interleaver operation. The experimental results show that the implemented all-pass MRR has a maximum extinction ratio (ER) of 38.9 dB and the corresponding quality factor is 6.5×104. The comb filter based on configured FP cavity can be switched from narrowband response (0.06 nm) to wideband flat-top response (0.23 nm), with ERs up to 10.6 dB and 22 dB, respectively. Moreover, a dynamic conversion between Lorentz, EIT, and Fano resonance line shapes based on the coupled resonant system can be realized. The demonstrated integrated device holds great potential for various applications such as filtering and switching in optical wavelength-division multiplexing (WDM) communication networks.

The development of g-C3N4-based photocatalysts with abundant active sites is of great significance for photocatalytic reactions. Herein, a smart and robust strategy was presented to fabricate three-dimensional (3D) g-C3N4nanosheet-coated alginate-based hierarchical porous carbon (g-C3N4@HPC), including coating melamine on calcium alginate (CA) hydrogel beads, freeze-drying hydrogel beads as well as pyrolysis at high temperatures. The resulting photocatalyst possessed a significantly high surface area and a large amount of interconnected macropores compared with porous carbon without the melamine coating. The unique structural features could effectively inhibit the curling and agglomeration of g-C3N4nanosheets, provide abundant photocatalytic active sites, and promote mass diffusion. Therefore, the g-C3N4@HPC composite exhibited remarkable photocatalytic activity and outstanding stability toward the photoreduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) by NaBH4under natural sunlight and simulated visible-light irradiation (λ > 420 nm) using a 300 W xenon lamp. Moreover, the mechanism toward the photocatalytic reaction was extensively studied by quenching experiments and electron spin resonance (ESR) experiments. The results showed that active hydrogen species were able to be achieved by following a dual-channel pathway in the NaBH4system, which included photocatalytic reduction of H+ions and photocatalytic oxidation of BH4–ions. This work not only opens up a new way to design efficient photocatalysts for various reactions but also provides a reference for an in-depth study of the photoreduction mechanism.

During the pyrite oxidation process, aqueous ferrous/ferric ions (Fe2+/Fe3+), as well as surface-adsorbed Fe2+/Fe3+, have been widely recognized to dominate hydroxyl radical (•OH) generation, while this study reveals that the secondary solid iron species also play non-negligible roles. Based on the different forms and the presence of sites, the secondary solid iron species were classified as Fecoat(iron-containing coating on the pyrite surface) and Fedep(ex situ-deposited iron (oxyhydr)oxide that is not in contact with pyrite). Instead of participating in building a stubborn passivation layer on the pyrite surface, Fecoatis easy to fall off from the pyrite surface as the oxidation of pyrite deepens, while large fractions of Fedepand Fecoatare found to be extractable with nitrilotriacetic acid (NTA). Achieved by cyclically oxidizing pyrite within different NTA levels (0/0.1/10 mM), Fecoatand Fedepwere proved to have distinct redox behavior during the pyrite oxidation process. Amorphous Fedep, originated from the hydrolyzation of dissolved Fe3+, accelerates the nonradical decay of hydrogen peroxide (H2O2); as a result, the accumulation of Fedepalways decreases the •OH production during the pyrite oxidation process. However, part of Fedepadsorbs on the pyrite surface through electrostatic attraction and converts into Fecoat. The electron conduction between Fecoatand pyrite was verified, which accelerates the oxidative dissolution of pyrite, produces reactive Fe(II), and therefore favors •OH generation. This study improves our understanding of the redox behavior of pyrite in complex media such as natural processes and practical engineering systems.

Metal-organic framework (MOF) materials with loaded catalysts have recently garnered substantial interest in the catalysis field. However, the catalytic performance of MOF catalysts is hindered by particle aggregation. This study introduces a microwave-assisted anchoring strategy to improve the dispersion of UIO-66-NH2on SiC surfaces. The dispersion can be effectively controlled by varying the SiC carrier content. Scanning electron microscopy and transmission electron microscopy analyses show that as the SiC content increases from 2% to 10%, MOFs exhibit a more dispersed distribution on the surface. This is exemplified in the esterification reaction between acetic acid and cyclohexene, where a higher MOF dispersion leads to a conversion rate boost from 70% to 75%. Numerical simulations reveal that microwave's selective heating property plays a crucial role in achieving this enhanced dispersion. This work contributes a systematic approach to enhance MOF dispersion and advances the development of structured catalysts based on MOFs.

Achieving high-quality (Q)-factor resonances in metasurfaces is essential for various applications, including nano-lasers, nonlinear optics, and quantum optics. In this work, we propose a high-Q metasurface using a topological strategy: constructing the metasurface by stacking two conjugated nanopillar arrays with different topological invariants. Our study shows that a topological edge state steadily appears at the interfaces of the nanopillars, and a sharp transmission resonance with a Q-factor of more than 1000 can be obtained. The sensing application of such high-Q topological metasurface is also demonstrated, whose figure of merit reaches approximately 145. The proposed strategy and underlying theory can open up new avenues to realize ultrasharp resonances, which can promote numerous potential applications, such as biosensing, optical modulation, and slow-light devices.

Due to the hydrolytic instability of LiPF6in carbonate-based solvents, HF is a typical impurity in Li-ion battery electrolytes. HF significantly influences the performance of Li-ion batteries, for example by impacting the formation of the solid electrolyte interphase at the anode and by affecting transition metal dissolution at the cathode. Additionally, HF complicates studying fundamental interfacial electrochemistry of Li-ion battery electrolytes, such as direct anion reduction, because it is electrocatalytically relatively unstable, resulting in a LiF passivation layer. Methods to selectively remove ppm levels of HF from LiPF6-containing carbonate-based electrolytes are limited. We introduce and benchmark a simple yet efficient electrochemical method to selectively remove ppm amounts of HF from LiPF6-containing carbonate-based electrolytes. The basic idea is the application of a suitable potential to a high surface-area metallic electrode upon which only HF reacts (electrocatalytically) while all other electrolyte components are unaffected under the respective conditions.

Tunable and reconfigurable materials with autonomic shape transformation in response to the environment have emerged as one of the most promising approaches for a variety of biomedical applications, such as tissue engineering, biosensing, and in vivo biomedical devices. Currently, it is still quite challenging to fabricate soft, microscaled 3D shape-reconfigurable structures due to either complicated microfabrication or limited microscale photopolymerization-based printing approaches to enable adaptive shape transformation. Here, a one-step photo-cross-linking approach has been demonstrated to obtain a 3D-to-3D morphological transformable microhelix from a self-rolled hydrogel microsheet, resulting in chirality conversion. It was enabled by a custom-designed “hard” stripe/“soft” groove topography on the microsheets for introducing, which introduced both in-planar and out-of-planar anisotropies. Both experiment and simulation confirmed that a stripe/groove geometry can effectively control the 3D transformation by activating in-planar or/and out-of-planar mismatch stress within the microsheets, resulting in switching of the rolling direction between perpendicular/parallel to the length of the stripe. Furthermore, versatile 3D microconstructs with the ability to transform between two distinct 3D configurations have been achieved based on controlled rolling of microhelices, demonstrated as “windmill”-to-“T-cross” and “cylinder”-to-“scroll” transformations and dynamic blossoming of biomimetic orchids. In contrast to conventional 2D-to-3D micro-origami, we have successfully demonstrated an approach for fabricating microscale, all-soft-material-based constructs with autonomic 3D-to-3D structural transformation, which presents an opportunity for designing more complex hydrogel-based microrobotics.