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Radar detection of maritime targets plays an important role in marine environment monitoring. For civil maritime detection in the areas of inshore coastal, pulse-compression radar is universally used owing to its low cost. The complex sea clutter in the practical application will greatly affect the received radar echoes. Due to the inability to accurately describe the differences in characteristics between sea clutter and maritime targets, the detection performance of methods based on mathematical derivation is not satisfactory in actual deployment. Recently, neural-based methods have made strides in many pattern recognition tasks, such as computer vision and natural language processing. The sophisticated deep neural models can be applied to different downstream tasks due to their powerful learning ability. Inspired by this idea, we propose a maritime radar target detection method in sea clutter based on deep learning. To better model the sequence correlation of radar echoes, we propose a Self-Adaption Local Augmented Long Short-Term Memory (SALA-LSTM) structure. The proposed SALA-LSTM integrates adaptive convolution into vanilla LSTM cells, which not only maintains the inherent overall sequence modeling ability of vanilla LSTM, but also strengthens its ability to perceive the correlation on a small scale in the local scope. Based on SALA-LSTM and other neural structures, we propose a radar target detection network. A measured dataset containing different typical scenarios is utilized to evaluate the detection probability and false alarm rate. The detection performance of our proposed network is superior to that of the existing methods. [ABSTRACT FROM AUTHOR]

Radar detection of maritime targets plays an important role in marine environment monitoring. For civil maritime detection in the areas of inshore coastal, pulse-compression radar is universally used owing to its low cost. The complex sea clutter in the practical application will greatly affect the received radar echoes. Due to the inability to accurately describe the differences in characteristics between sea clutter and maritime targets, the detection performance of methods based on mathematical derivation is not satisfactory in actual deployment. Recently, neural-based methods have made strides in many pattern recognition tasks, such as computer vision and natural language processing. The sophisticated deep neural models can be applied to different downstream tasks due to their powerful learning ability. Inspired by this idea, we propose a maritime radar target detection method in sea clutter based on deep learning. To better model the sequence correlation of radar echoes, we propose a Self-Adaption Local Augmented Long Short-Term Memory (SALA-LSTM) structure. The proposed SALA-LSTM integrates adaptive convolution into vanilla LSTM cells, which not only maintains the inherent overall sequence modeling ability of vanilla LSTM, but also strengthens its ability to perceive the correlation on a small scale in the local scope. Based on SALA-LSTM and other neural structures, we propose a radar target detection network. A measured dataset containing different typical scenarios is utilized to evaluate the detection probability and false alarm rate. The detection performance of our proposed network is superior to that of the existing methods. [ABSTRACT FROM AUTHOR]

Using photovoltaic (PV) energy to produce hydrogen through water electrolysis is an environmentally friendly approach that results in no contamination, making hydrogen a completely clean energy source. Alkaline water electrolysis (AWE) is an excellent method of hydrogen production due to its long service life, low cost, and high reliability. However, the fast fluctuations of photovoltaic power cannot integrate well with alkaline water electrolyzers. As a solution to the issues caused by the fluctuating power, a hydrogen production system comprising a photovoltaic array, a battery, and an alkaline electrolyzer, along with an electrical control strategy and energy management strategy is proposed. The energy management strategy takes into account the predicted PV power for the upcoming hour and determines the power flow accordingly. By analyzing the characteristics of PV panels and alkaline water electrolyzers and imposing the proposed strategy, this system offers an effective means of producing hydrogen while minimizing energy consumption and reducing damage to the electrolyzer. The proposed strategy has been validated under various scenarios through simulations. In addition, the system's robustness was demonstrated by its ability to perform well despite inaccuracies in the predicted PV power. [ABSTRACT FROM AUTHOR]

To simulate the effects of ionizing irradiation on photo-thermo-refractive (PTR) glass in a cosmic environment, the optical properties changes under ionizing irradiation (γ-, X- and UV-ray) were investigated on PTR-glass with and without Ag doped (named as PTR-S and PTR-F, respectively) samples. Thermoluminescence (TL), transmission electron microscopy (TEM) measurements, UV-VIS absorption spectroscopy analysis, Gaussian peak fitting, and continuous wave electron paramagnetic resonance (CW-EPR) were used to determine the species of the irradiation-induced color centers. The radiation resistance properties of the Ag-species on the PTR-S glass were evaluated by comparing the defect center concentrations in the irradiated PTR-S and PTR-F glasses. The results showed that absorption in PTR-F and PTR-S glass increased significantly with increasing γ-irradiation dose, which was related to HC 1 , HC 2 , E′, L, ETC defect centers and Ag-species, and the formation of HC 1 , HC 2 , E', and L-centers was reduced by the doping of Ag into the PTR-S glass matrix. Compared with the γ-irradiation, X-irradiation showed a similar effect. In comparison, UV-irradiation induced fewer defect centers and smaller Ag (NPs). This discrepancy could be caused by variations in photon energies. [ABSTRACT FROM AUTHOR]

ZIF-8 and ZIF-67 are two highly similar Zeolite iminazolate frameworks (ZIFs) materials. In the field of adsorption, ZIF-8 is more suitable than ZIF-67 in most cases. In the field of catalysis involving electron transfer, ZIF-67 is more reliable. Using these two materials for modification and activation of peroxymonosulfate (PMS), ZIF-67 is a cobalt based metal catalyst, while ZIF-8 volatilizes the zinc node at a calcination temperature above 800 ℃, thereby transforming into a non-metallic catalyst. Generally speaking, ZIF-67 derivatives have better activation effects, while ZIF-8 derivatives have less metal leaching and no concerns about secondary pollution. In addition, some researchers have combined ZIF-8 with ZIF-67 in the hope of combining their advantages. These three types of materials can generate a large number of free radicals and non - radicals by activating PMS, achieving the effect of degrading pollutants. [Display omitted] • Different performances of ZIF-8 and ZIF-67 were illustrated. • The latest progress in improving PMS activation by ZIF-8 and ZIF-67 derivatives. • The advantages and disadvantages of metal catalysts and non-metal catalysts. • Prospects for future research on zinc-cobalt synergistic activation of PMS in AOPs. Zeolite imidazolate frameworks materials (ZIFs, especially ZIF-8 and ZIF-67) used as catalysts for peroxymonosulfate (PMS) activation to generate reactive oxidative species (ROS), such as free radicals and singlet oxygen radicals, for the degradation of organic pollutants in the advanced oxidation processes (AOPs) have received much attention recently. The synthesis and modification methods of ZIF-8 and ZIF-67 were introduced in detail, particularly based on the specificity generated by the differences in the characteristics of the material itself. In additional, the modification of ZIF-8/ZIF-67 composites for activating PMS was systematically discussed for the first time. The feasibility and possible development directions of zinc-cobalt co-catalysis were proposed. Finally, the potential active sites of modified materials in the catalytic process were summarized, the degradation mechanism were elucidated, and the difficulties and challenges that ZIFs still need to face in activating PMS in the future were explained. [ABSTRACT FROM AUTHOR]

[Display omitted] • A graphene-loaded transition metal single-atom catalyst doped with nitrogen atoms was designed. • Five catalysts with excellent NRR catalytic performance were screened from 406 catalysts, with the lowest limiting potential of 0.31 V. • Screening strategy: ① The adsorption energy of N 2 ＜ 0.5 eV; ② The free energy barriers for the first and last hydrogenation reactions ＜ 0.4 eV; ③ The free energy of desorption of NH 3 ＜1 eV; ④ Better NRR selectivity than HER. Nitrogen reduction reaction (NRR) is necessary as an environmentally friendly and sustainable method for producing NH 3 in the context of the energy crisis and increasing environmental concerns. Efficient catalysts play an important role in the NRR reaction. In this work, a high-curvature tetracoordinate transition metal (TM) nitrogen-doped graphene single-atom catalyst was designed and five candidate catalysts with excellent performances were selected from 406 models through a combination of high-throughput screening and density functional theory calculations. Using seven different coordination types MC 4 , MC 3 N 1 , MC 2 N 2 -1, MC 2 N 2 -2, MC 2 N 2 -3, MC 1 N 3 and MN 4 , of which VN 4 (side-on) with four N-atom coordination has the lowest limiting potential of 0.31 V and the competing Hydrogen Evolution Reaction (HER) was suppressed. This work provides guidance for the development of efficient NRR catalysts. [ABSTRACT FROM AUTHOR]

During actual operation, the superhydrophobic surface provides excellent resistance to condensation and icing due to its low wettability. This study used an Ar/HMDS mixture as the working gas and a low-temperature plasma jet induced in an atmospheric pressure environment to create a superhydrophobic coating with a water contact angle of up to 172.6°, utilized a typical epoxy resin plate as the substrate. XPS analysis indicated the presence of a significant number of low surface energy functional groups containing Si and O on the epoxy resin surface. Scanning electron microscope (SEM) revealed the presence of dense microstructure and nanostructure on the surface. The process of plasma jet water-repellent modification of epoxy resin surface was further analyzed from two perspectives: particle collision in the electric field, molecular bond breaking and reorganization reaction of monomer, and grafting reaction of free radicals formed on the surface of epoxy resin by high-energy jet bombardment, combined with XPS test of high-purity discharge products in the jet tube. The results indicate that the epoxy resin surface modified by plasma jets achieves superhydrophobicity. The modification time is extended to 180 s, and the static water contact angle is increased from 72.4° to 172.6°. Dense microparticle and nanoparticle are formed on the surface. For the secondary binary composite rough structure, the percentage of Si and O elements increased to 41.3% and 27.8%, respectively. The Si(CH3)O3/2 system contributed the most, accounting for 40.5%. [ABSTRACT FROM AUTHOR]

The Potential Transformer (PT) plays an important role in the measurement and monitoring of the power system. The accurate modeling of the PT is very important but not yet perfect. The stray capacitance will have a non-negligible effect on the performance of a PT. However, the influence of stray capacitance is rarely considered in existing models, which makes the broadband simulation performance weak and provides limited references in engineering. In this paper, a calculation method of PT stray capacitance is proposed to analyze the performance of the PT at different frequencies and extract the capacitive current of the PT port. This paper used a non-destructive method to obtain the test data of a PT, calculated the value of the stray capacitance, and drew the hysteresis loops of the iron core. A corresponding simulation model was established to predict the PT performance at different frequencies. The simulation results are in good agreement with the experimental data, which proves the accuracy of the modeling parameters. The data processing logic is clear and is easy to be simplified by programming, which makes it promising in engineering. [ABSTRACT FROM AUTHOR]

It is essential to carry out an AC voltage withstand test after GIS extension and maintenance. At present, the common methods of GIS AC withstand test include double isolation gap, reduce the test voltage, and narrow test range. These methods generally have some defects: such as complex test processes, all bus de-energized, some apparatus failed to test, unreliable test results and so on. This paper presents a distinctive GIS AC voltage withstand test method. The method controls the phase-frequency parameters of the test voltage so that it maintains the same phase-frequency relationships as the in-service bus voltage during the process of testing. In this situation, the GIS can carry out an energized AC voltage withstand test. The process of AC withstand voltage test method based on phase-frequency control (PFC) is introduced in detail, and the feasibility of this method is verified. The phase difference margin of the PFC method is optimized through simulation and numerical calculation, and a variety of protection measures are proposed to ensure the safety of the test process. The proposed PFC AC voltage withstand test method will not affect the in-service bus and has great practical application value for the field GIS AC voltage withstand test.0F. [ABSTRACT FROM AUTHOR]

Estimation of nitrogen content in crop leaves using hyperspectral techniques encounters the challenge of limited model stability. In this study, a method for the construction of nitrogen estimation model of oilseed rape (Brassica napus L.) was proposed, which combines the spectral features of nitrogen and nitrogen-containing physiological components. Based on the pot experiment, a total of 320 sets of canopy spectra were collected in the five growth stages using hyperspectral technology, and the concentration of leaf nitrogen (LNC), malondialdehyde (MDA), proline, soluble sugar (SS), and water were determined in indoor chemical experiments. Original spectra was preprocessed by five kinds of spectral conversions, and the random frog (RF) method was used to screen the spectral features of nitrogen and nitrogen-containing physiological components that were used to construct the partial least square regression (PLSR) and support vector machine (SVM) models. The results showed that the selection of spectral features of LNC and nitrogen-containing physiological components based on RF greatly reduced the collinearity and redundant information among bands. The accuracy of the models based on the spectral features of LNC and nitrogen-containing physiological components were higher than that of the model based on the spectral features of single LNC. Further interannual test showed that the prediction accuracy of the N + MDA + SS model was higher than that of other models, especially at the rapid growth stage, with R2 of 0.871. This study provides a new idea for improving the accuracy and stability of crop nitrogen estimation model. [ABSTRACT FROM AUTHOR]

[Display omitted] • UHP has higher electron utilization and targeting efficiency compared to H 2 O 2. • The nonpolar performance of O-O in UHP in water is weaker than H 2 O 2. • UHP undergoes electron transfer easily with Fe2+ to form more stable complexes. • Less energy is required for the degradation of BPA by UHP/Fe(II) An advanced Fenton technique using urea peroxide (UHP) as an oxidant was studied for the degradation of bisphenol A (BPA) in aqueous solution. Compared to the H 2 O 2 /Fe(II) system, the UHP/Fe(II) system performs noticeably better in terms of degradation and requires less catalyst. The mechanism by which UHP exhibits unique and remarkable properties has been elucidated at the molecular level (bond order, AIM analysis, ELF, Spin Population number, electron difference density maps) by density functional theory (DFT) calculations. The ELF and the electron density difference revealed that UHP created an intermediate coordination compound with six-coordinated iron (II), facilitating electron transfer and the disruption of O-O bonds because of the feeble O-O strength, leading to an increase in hydroxyl radicals. Consequently, UHP increases the rate of electron usage and targeting efficiency, which accelerates the breakdown of BPA. targeting efficiency, which accelerates the breakdown of BPA. Based on the intermediates determined by LC-MS/MS, the possible degradation pathway of BPA in the UHP/Fe(II) system were proposed, which was verified to be a lower energy consumption pathway by calculating the reaction energy barriers. It is expected to be an advanced Fenton technology with practical engineering applications potential, due to the advantages of wider pH window, lower energy consumption and higher electron utilization. [ABSTRACT FROM AUTHOR]

Hydrogen energy is a clean, zero‑carbon, flexible and abundant secondary energy. The large-scale deployment of industrial hydrogen production equipment is an effective way to improve renewable energy consumption, the efficiency of hydrogen production from water electrolysis is crucial for equipment deployment. In this paper, a novel industrial magnetically enhanced AWE electrolyzer is designed to improve the efficiency of hydrogen production. The structure and assembly method of the magnetic bipolar plate are introduced, the BOP component is designed and an industrial system-level test platform is built. The results show that the magnetic enhanced electrolyzer can effectively improve the hydrogen production efficiency, however, the effects of different magnetic field configurations (Magnetic field horizontal configuration, MFHC; Magnetic field vertical configuration, MFVC; No magnetic field configuration, NMFC) are significantly different. The magnetic field of MFVC are concentrated inside the bipolar plate and perpendicular to the direction of the electric field, and there is almost no magnetic flux leakage inside the cathode and anode cells. The magnetic field and the electric field of the MFHC configuration are not completely perpendicular, the magnetic field distribution is irregular, there are more magnetic flux leakage in the cells, and the magnetic field intensity is obviously greater than that of the MFVC configuration. Compared with NMFC, MFHC and MFVC significantly improved the hydrogen production efficiency, MFHC performance is better, the current density increased by 28.48% (@50 °C-100 L/h-2 V cell voltage-30%wt KOH), DC power consumption was reduced by 6.2% (CC100A-100 L/h-30%wt KOH). The design method and configuration scheme of magnetically enhanced electrolyzer provide a new idea for the industrial application of magnetic fields in AWE hydrogen production equipment. [Display omitted] • A novel industrial magnetically enhanced electrolyzer is designed. • This article proposes optimized the magnetic field configuration suitable for industrial electrolyzer. • Magnetic field configuration can be switched by rotating electrolyzer, horizontal configuration has better performance. • This study provides a novel way for the application of magnetic field in industrial electrolyzer. [ABSTRACT FROM AUTHOR]

Most of the available overvoltage sensors are too sensitive to the installation angle and inducing direction. Even a slight angular deflection will cause a nonnegligible error to the measurement. To reduce the impact caused by angular deflection, in this article, we propose a new spherical six-electrode overvoltage sensor to improve the measuring accuracy and stability. First, we presented the 3-D electric field ($E$ -field) coupling mechanism, vector synthesis method, design, and output properties of the proposed sensor. Second, we obtained the relationship between the structural parameters and the equivalent capacitance by the finite-element method (FEM). Finally, we completed the steady-state test, transient test, and 3-D angular deflection test. From the results, the sensor has a broad bandwidth of 1.2 MHz, a phase error of less than 1.8°, and good linearity of the output signals. In the case of 3-D angular deviations, the mean relative error (MRE) of the sensor is lower than 2.55%, with a maximum standard deviation (SD) of 0.088%, which proves that the output of the proposed sensor is well consistent with the overvoltage signal, and its accuracy is almost immune to the angular deflection. [ABSTRACT FROM AUTHOR]

The early screening and prevention of chronic respiratory diseases are very important. To achieve the monitoring and management of chronic obstructive pulmonary disease (COPD), this article proposes a new lung impedance measurement method, which uses a cross four-electrode structure. It effectively solves the problems of noncompliance of traditional instruments, risk of cross-infection, and nononline monitoring. Compared with the traditional impedance measurement method, the measurement accuracy of lung function parameters is improved. Using the detection device, the equivalent impedance of the chest was rapidly measured from two orthogonal directions when the people were in the same breath state. The maximum expiratory and inspiratory thoracic impedance was obtained by analyzing 30 samples. The measurement of lung function parameters is realized by solving the change value of impedance and its relationship with the chest circumference. Experiments proved that the cross four-electrode method could consider the two directions of equivalent thoracic impedance, enrich the measurement parameters of thoracic impedance, and make the test results of pulmonary function parameters have good consistency with the results of standard methods. Correlation coefficients of test indexes forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were 0.967 and 0.955 respectively. The consistency boundary diagram showed that more than 95% of monitoring data of the subjects fell within the scope of the consistency boundary, and the maximum relative error of measurement was only 4.65%. [ABSTRACT FROM AUTHOR]

Ultra-high purity Corning 7980 and Corning 7979 silica glasses, respectively with high and low contents of hydroxyl and hydrogen, were specifically selected to investigate the effects of O 2 loading on the 1.9 eV red luminescence of the gamma-ray induced non-bridging oxygen hole center (NBOHC), whose luminescence intensity is beneficial not only to predict the laser damage of silica but also to the targeted improvements in the preparation-treatment processes of silica. The UV trasmittance spectra, the UV excitation spectra, the visible emission spectra and the red emission lifetime decay curves were determined for these two types of the gamma-ray irradiated silica glasses before and after O 2 loading. The content ratios of Si dangling bond (Si-E′) to NBOHC in silica glasses before and after O 2 loading are estimated. The formation precursors and other related defects for NBOHC, such as Si-E′, Si-O-Si bond, Si-O-H bond, peroxy radical and linkage, oxygen-deficient centers ODC(I) and ODC(II), etc, are discussed. The bandwidths of the excitation and emission spectra before and after O 2 loading are compared at the lower energy side of the spectra. The average emission lifetimes and especially the decay curves of the red luminescence before and after O 2 loading are analyzed. There appear two types of NBOHCs with and without neighbouring hydrogen interaction at room temperature, respectively corresponding to the shorter and longer lifetime components. After O 2 loading, the shorter lifetime component disappears and becomes the longer one, indicating that the hydrogen-bonded NBOHC is altered into the non-bonded. It is suggested that the analysis of the shorter and longer lifetime components of the red luminescence can be utilized in the laser damage prediction as well as the preparation and treatment processes of silica. • O 2 loading affects formation mechanism and red luminescence of non-bridging oxygen hole center used to predict laser damage. • Two types of NBOHCs with/without neighbouring hydrogen interation, corresponding to shorter and longer lifetime comonents • Short lifetime component becomes the long one after O 2 loading, proving that H-bonded NBOHC is altered into the non-bonded. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimal electrode configuration for industrial alkaline water electrolyzer. • Balance of Plant system design with full automatic running function. • Achieved 4.3kWh/m3H 2 @4000 A/m2 based on the optimized configuration. • Provided reference and guidance for electrode parameter selection and system design. • This study contributes to the deployment of more efficient industrial electrolyzer. The production of green hydrogen by water electrolysis is an effective way to realize the utilization of renewable energy and decarbonization, efficient water electrolysis equipment is of great significance to reduce energy consumption and accelerate the deployment of hydrogen production infrastructure. This paper reports the optimal electrode configuration adapted to actual industrial conditions. The aim of this paper is to study the electrode structure effect and system design of compactly-assembled industrial electrolyzer under the actual operating conditions, so as to find out more suitable electrolyzer configuration parameters. Firstly, the principle and structural parameter design of industrial electrolyzer are carried out, and compactly-assembled industrial alkaline water electrolyzer (22 cells) was manufactured. Secondly, a balance of plant (BOP) system was built and the fully automatic operation process was designed. Finally, a system-level alkaline water electrolysis (AWE) hydrogen production system (including compactly-assembled electrolyzer and BOP) was established. The effect of different expanded meshes and woven meshes on the energy consumption of AWE equipment was tested, and the system component cost was analyzed. Industrial system-level test results show that the electrode dominant parameters affecting AWE performance are different under varying current densities. From the perspective of industrial application, it is more suitable for the strand width and pore width of the woven mesh to be about 0.2 mm, it achieved 4.3kWh/m3H 2 @4000 A/m2 based on the optimized configuration parameters. This study is helpful to the selection of electrode parameters and optimal configuration for industrial AWE equipment, at the same time, it provides a reference for the design of electrolyzer, BOP and system control process. [ABSTRACT FROM AUTHOR]

• Two novel CCAs have been identified from Bosea sp. OK403 and Roseomonas rosea. • 2.8-fold improvement in specific enzyme activity and k cat /K m values were achieved. • Hydrolysis of 14 β-lactam antibiotics were investigated with up to 94 % conversions. • Semi-preparative reactions were performed with conversions up to 97 % in 8 h. 7-Aminocephalosporanic acid (7-ACA) is the core nuclei for the synthesis of β-lactam antibiotics. Cephalosporin C acylases (CCAs) are a class of enzymes that enable the hydrolysis of cephalosporin C (CPC) to 7-ACA. In this study, we identified, characterized and engineered new CCAs to prepare 7-ACA. The best mutant A14 (L159S/A419V) was obtained after several rounds of semi-rational enzyme design using the combinatorial active-site saturation testing (CAST) and iterative evolution. A 2.8-fold increase in specific enzymatic activity (6.1 U/mg) was obtained compared to the wild-type enzyme. The engineered variant also enabled the hydrolysis of a variety of β-lactam antibiotics including Penicillin G and phenylacetyl-7-aminodeacetoxycephalosporanic acid (G-7-ADCA). Overall, this study discovered new CCAs from distinct bacterial origins and enabled the synthesis of various core β-lactam antibiotics nuclei. [Display omitted] [ABSTRACT FROM AUTHOR]

Cold-regulated (COR) genes, located downstream of the C-repeat binding factors (CBFs) in cold signaling pathways, play a central role in plant response to cold stress. In our previous studies, a Cor413 chloroplast envelope membrane protein, PsCor413im1, was identified from the cold-tolerant plant Phlox subulata. Its overexpression enhanced cold tolerance and altered AtCor15 expression in Arabidopsis. In the present study, the function of PsCor413im1 was further investigated. Transmission electron microscope observation showed that the chloroplast envelope membrane of cold-treated transgenic Arabidopsis seedlings was more stable than that of cold-treated wild-type seedlings. Subcellular localization of green fluorescent protein as a marker revealed that the N-terminal and putative third transmembrane domain (TMD) of PsCor413im1 were essential for its targeting of the chloroplast envelope membrane. Furthermore, overexpression of PsCor413im1 fragments containing N-terminal and third TMD also altered the expression of AtCor15 genes in Arabidopsis. Overall, our results suggest that PsCor413im1 may stabilize the chloroplast envelope membrane under cold stress, and its N-terminal and third TMD are important for its targeting capability and function. • The N-terminal of PsCor413im1 were essential for its targeting. • The third transmembrane domain of PsCor413im1 were essential for its targeting. • Overexpression of PsCor413im1 fragments also altered the expression of AtCor15 genes. [ABSTRACT FROM AUTHOR]

The voltage-controlled graphene-mediated surface-enhanced Raman scattering (G-SERS) spectroscopy is experimentally developing spectral technology, and which is prosperously applied in the fields of ultra-sensitive spectral analysis, sensor and catalysis. In this review, we introduce the physical principle, fabrication method, and recent applications of voltage-controlled G-SERS. We firstly introduce fabrication methods of voltage-controlled G-SERS substrate, based on the hybrid between graphene and noble metal. Secondly, the physical mechanism of voltage-controlled G-SERS is proposed for exploring the advantages of voltage-controlled G-SERS over traditional SERS. The plasmon–exciton coupling for G-SERS substrate is of greatly advantages than SERS substrate enhanced by plasmon only. The plasmon-exciton coupling can result in plexciton, and then G-SERS can also be considered as a kind of plexciton-enhanced Raman scattering (PERS). Thirdly, recent advances of voltage-controlled G-SERS on applications in spectral analysis; sensor and catalysis, especially on surface catalytic reactions, are summarized in detail. This review can not only promote deeper understating of physical principle on voltage-controlled G-SERS, but also promote potential applications in physical, chemical, material, spectral and environmental fields. [ABSTRACT FROM AUTHOR]

At present, the method of obtaining the voltage of transmission lines by using the inverse problem of the electric field is generally faced with the difficulties of solving data equations. Aiming at the above problems, the method that solves transmission wire voltage through spatial electric field integration based on D-dot sensor is proposed. In this paper, with the ground as the reference potential and the vertical line of the transmission line to the ground as the integral path, D-dot electric field sensor is applied to measure the instant electric field values of several nodes on the integral path and the transmission wire voltage is directly solved combined with Gauss–Legendre numerical integration algorithm. The Gauss–Legendre algorithm is verified by the electric field distribution data on the integration path obtained by simulation. Furthermore, the improvement of the Gauss–Legendre algorithm is realized through optimizing the integral interval so that the location of integral nodes is more reasonable. Finally, the measurement system based on LabVIEW is designed and the experiment platform of the analog transmission line is constructed. Experiment results show that the measurement method of transmission wire voltage through the improved Gauss–Legendre algorithm based on D-dot sensor owns high accuracy with an error of less than 1%. [ABSTRACT FROM AUTHOR]

Adopting the direct $Z$ -transform ($\text{D}Z\text{T}$) method due to its higher accuracy instead of the approximate $Z$ -transform ($\text{A}Z\text{T}$) methods and efficient and switchable truncations between the 1st- and 2nd-order uniaxial perfectly matched layers (UPMLs) with the complex-frequency-shifted (CFS) scheme are shown to terminate the relevant finite-difference time-domain (FDTD) regions. The proposed $\text{D}Z\text{T}$ -CFS-UPML formulations can possess the switchable function in terms of relevant FDTD problems so that the optimal performance can be obtained with the tradeoff among memory requirement, CPU time, and absorption accuracy. For the FDTD problem with the strong evanescent and weak low-frequency propagating waves, the proposed $\text{D}Z\text{T}$ -CFS-UPML formulations can be switched to the 1st-order PML truncation, and for the other cases with both low-frequency propagating and strong evanescent waves, the 2nd-order PML is the best choice. Two numerical simulations have been carried out to illustrate the validity and flexibility of the proposed approach. [ABSTRACT FROM AUTHOR]

Flexible pressure sensors based on micro‐/nanostructures can be integrated into robots to achieve sensitive tactile perception. However, conventional symmetric structures, such as pyramids or hemispheres, can sense only the magnitude of a force and not its direction. In this study, a capacitive flexible tactile sensor inspired by skin structures and based on an asymmetric microhair structure array to perceive directional shear force is designed. Asymmetric microhair structures are obtained by two‐photon polymerization (TPP) and replication. Owing to the features of asymmetric microhair structures, different shear force directions result in different deformations. The designed device can determine the directions of both static and dynamic shear forces. Additionally, it exhibits large response scales ranging from 30 Pa to 300 kPa and maintains high stability even after 5000 cycles; the final relative capacitive change (ΔC/C0) is <2.5%. This flexible tactile sensor has the potential to improve the perception and manipulation ability of dexterous hands and enhance the intelligence of robots. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bio-inspired dynamic structural color skin responses to external stimulation. • Heterogeneous strategy endows smart hydrogel with capability of actuating. • One-step 4D printing for integrating actuation and sensing. • Structural color skin senses the state and posture of microrobots. Recent advancements in materials, nanofabrication, actuation, and sensing have facilitated the development of untethered microrobots. However, realizing sub-millimeter-integrated microrobots with actuation, perception, and wireless communication capabilities remains elusive. In this study, we present the successful fabrication of chemotactic microrobots at the micron scale, featuring integrated iridescent structural color surfaces that can be utilized for robot motion control through optical tracking. Using a pH-responsive biopolymer as the carrier, we have created microrobots that employ bilayer joints, mimicking the actuation characteristics observed in arthropods. Additionally, biomimetic microstructures with structural color functionality have been incorporated onto the surface of the robots, serving as an optical-communication skin. The robots are actuated through reversible expansion triggered at the phase transition threshold of the biopolymer, while their geometric states and posture information are acquired by converting the volume strain into color variations. This research can potentially establish a critical pathway for developing state-feedback-controlled microrobots for future biomedical applications. [ABSTRACT FROM AUTHOR]

Arsenic pollution in environment has always been an important environmental problem that has attracted wide attention in recent years. Adsorption is one of the main methods of treatment for arsenic in the aqueous solution and soil because of the advantages of high efficiency, low cost and wide application. Firstly, this report summarizes the commonly and widely used adsorbent materials such as metal–organic frameworks, layered bimetallic hydroxides, chitosan, biochar and their derivatives. The adsorption effects and mechanisms of these materials are further discussed, and the application prospects of these adsorbents are considered. Meanwhile, the gaps and deficiencies in the study of adsorption mechanism was pointed out. Then, this study comprehensively evaluated the effects of various factors on arsenic transport, including (i) the effects of pH and redox potential on the existing form of As; (ii) complexation mechanism of dissolved organic matter and As; (iii) factors affecting the plant enrichment of As. Finally, the latest scientific researches on microbial remediation of arsenic and the mechanisms were summarized. The review finally enlightens the subsequent development of more efficient and practical adsorption material. [Display omitted] • DOM is prone to coordinate with heavy metals in soil. • Adsorbents have different tolerance conditions to the environment. • Transporter proteins reduce the arsenic enrichment in plant. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we theoretically analyze the nature of chirality induced by molecular self-assembly with molecular dynamics and visualization methods. Firstly, the dynamics of molecular self-assembly of biphenylenes system are demonstrated in detail. Secondly, the molecular interactions for the assembled molecules are analyzed with the weak intermolecular forces. Thirdly, electron-hole coherence and charge transfer in optical absorption are demonstrated with a transition density matrix and charge difference density, respectively. The detailed visualized analysis of electric and magnetic transition dipole moment integrals reveals the nature of chirality of assembled molecules in electronic circular dichroism (ECD) spectroscopy. The Raman optical activity (ROA) spectra demonstrate that the chirality of assembled molecules is strongly dependent on the pre-resonance Raman spectra, based on the optical absorption and ECD spectroscopy. Our visualized analysis method can well reveal the nature and origin of chirality of molecular self-assembly. Graphical Abstract Unlabelled Image Highlights • Firstly, the dynamics of molecular self-assembly of biphenylenes system are demonstrated in detail. • Secondly, the molecular interactions for the assembled molecules are analyzed with the weak intermolecular forces. • Thirdly, electron-hole coherence and charge transfer in optical absorption are demonstrated with a transition density matrix and charge difference density, respectively. • The detailed visualized analysis of electric and magnetic transition dipole moment integrals reveals the nature of chirality of assembled molecules in ECD spectroscopy. • The ROA spectra demonstrate that the chirality of assembled molecules is strongly dependent on the pre-resonance Raman spectra. [ABSTRACT FROM AUTHOR]

UV detection has been generally used in external insulation detection of equipment. Currently used detection methods have many shortcomings, such as incomprehensive consideration of influencing factors, poor model adaption, and low accuracy. We propose a method that detects the ultraviolet pulse number (P), temperature (T), and humidity (H). Meanwhile, discharge intensity (J') was preliminarily estimated by UV detection using a fuzzy algorithm. Next, the ANFIS algorithm with a self‐study mechanism and an artificial neural network was introduced, which assessed that the discharge intensity is J. A UV detection circuit was established while carrying out a field test. The preliminary evaluation data of the fuzzy were used as training and testing data of ANFIS. The optimized model was obtained after ANFIS multiple trainings. Experimental results show that the relationships between P, T, H, and J in the optimized model are consistent with those of theoretical deduction. The assessment results remain highly stable with the occurrence of changes in external conditions, which indicates the feasibility of the ANFIS algorithm in UV detection of discharge intensity of electric equipment. This study can provide effective suggestions for online insulation monitoring and equipment maintenance. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Magnetic Field Pre-polarization (MFPP) method is proposed to improve the efficiency of hydrogen production. • MFPP is easy to match with high-power industrial AWE equipment. • MFPP improve the hydrogen production efficiency by a maximum of 9.2%. • The MFPP method provides a way for improving the efficiency of industrial AWE system. Water electrolysis can become a promising mean to produce clean hydrogen. Improving the efficiency of water electrolysis is of great significance for accelerating the development of large-scale hydrogen production equipment and low-carbon economy. This paper presents a novel method for enhancing the alkaline water electrolysis (AWE) efficiency by Magnetic Field Pre-polarization (MFPP), which is easily matched to high-power industrial AWE system. Firstly, compactly-assembled structure and energy consumption of industrial AWE electrolyzer are analyzed. Secondly, the MFPP method was proposed to enhance the efficiency of AWE. The structure parameters of MFPP equipment are optimized by simulation and the physical model is designed. Finally, a system-level equipment was developed to evaluate the effect of MFPP on the performance of the alkaline water electrolysis (AWE) system. Repeatability measurement, I-V characteristic analysis and error statistics were carried out under different working conditions. The effectiveness of MFPP method has been proved on industrial electrolyzer (with 22 cells). Compared with the electrolysis voltage of 40 V-42 V@22_cell, the efficiency improvement is more significant when the voltage is in the range of 42–46 V@22_cell. Under the 0.75 T MFPP, the maximum hydrogen production efficiency increased by 9.2 %. The mean absolute deviation (MAD) of test results is less than 1.88 (with a proportion of 0.11 %) and the mean squared error (MSE) is less than 0.49. [ABSTRACT FROM AUTHOR]

A double differential D-dot overvoltage sensor is proposed based on the D-dot principle for the purpose of faster and more accurate measurement of overvoltage signals. The proposed sensor is a new D-dot sensor structure consisting of four electrodes. It is applied together with the double differential input structure. This structure allows the sensor to operate in self-integration mode and achieve a wide frequency response characteristic while has a stronger anti-interference capability. The simulation demonstration and parameter design are carried out by using the Ansoft Maxwell. A test platform is constructed and used in the steady-state performance and lightning impulse transient-state test of the sensor. Test results demonstrate that the double differential D-dot sensor has satisfying steady-state performances, manifested by small measurement phase and amplitude errors. It can be applied to internal overvoltage measurement of power system. Moreover, the double differential D-dot sensor is equipped with good transient characteristics. The relative error of the lightning wave rise time which is measured by the double differential D-dot sensor is controlled in the range of ±1.7% and the relative measurement error of lightning wave peak is smaller than ±2.0%. It can measure external overvoltages effectively. [ABSTRACT FROM AUTHOR]

Remarkable variances were observed in permanent deformation curves of a dense asphalt mixture captured in triaxial repeated load permanent deformation (TRLPD) tests. In order to explore the causes of such variances, each permanent deformation curve was characterized firstly by an indicator ( B ) of the permanent deformation rate at a steady state stage. Meanwhile, a linear relationship was found between the values of indicator B and the resilient moduli of specimens after 1000 load repetitions. Secondly, a profound discussion on the potential relationship between resilient moduli and air voids content was performed. The discussion showed that air voids content appears to have no contributions to the observed variances. Nevertheless, three failure modes, tension failure, shear failure and shear failure with barreling, were observed in the X-ray Computed Tomography (CT) images of failed specimens subjected to triaxial compressive stresses. Furthermore, a significant correlation between failure modes and the resilient moduli was found by means of one-way analysis of variance (ANOVA). Moreover, it was found that the internal weak zones observed in the CT images of intact specimens dominate the behavior of the permanent deformation of asphalt mixture and the internal structure is the essential cause of such variances in the case of this study. This exploration highlights the influence of the internal structure on the mechanical performance of asphalt materials and thus recommends that considerable attention should be paid on the internal structure other than the volumetric properties when selecting test specimens. [ABSTRACT FROM AUTHOR]

Abstract: In this review, we firstly reveal the physical principle of plasmon‐exciton coupling interaction with steady absorption spectroscopy, and ultrafast transition absorption spectroscopy, based on the pump‐prop technology. Secondly, we introduce the fabrication of electro‐optical device of two‐dimensional semiconductor‐nanostructure noble metals hybrid, based on the plasmon‐exciton coupling interactions. Thirdly, we introduce the applications of plasmon‐exciton coupling interaction in the field of surface catalytic reactions. Lastly, the perspective of plasmon‐exciton coupling interaction and applications closed this review. [ABSTRACT FROM AUTHOR]

Eddy-current loss will cause waste of electric energy and affect service life of cable. In order to study the method of reducing eddy-current loss of cable trench in metal top pipe, a finite element simulation model was established. Firstly, influence factors of eddy-current loss were determined through a theoretical analysis, including arrangement mode of cable phase, top pipe size and cable distance. Finite element method was then used for optimal calculation of structure of cable trench and effective optimization design method was proposed. Results indicate that: for three-phase multiloop cable trench of metal top pipe, phase arrangement mode has important influence on eddy-current loss. For top pipe size, a comprehensive consideration of eddy-current loss and pipe stability should be taken in the thickness selection, and slotting position could only be at the position with maximum loss density. Both increase of distance between cable loop and top pipe and reduction of spacing between cables on the same loop will contribute to reduction of eddy-current loss of top pipe. Therefore, a cable trench structure commonly used in engineering was optimized and then its eddy-current loss was reduced by 70% effectively. [ABSTRACT FROM AUTHOR]

By modification of silane coupling agent, the TiO 2 nanocrystal seeds layer was loaded on the surface of fly ash carriers. Based on that, the hydrothermal method was adopted to synthetize the one-dimensional (1-D) TiO 2 which were loaded on the carriers densely under the condition of a low concentration TiO 2 precursor. Because of the calcination residual of modifier, the transmission and diffusion of ions on the surface of TiO 2 would be hindered, and the 1-D TiO 2 with porous surface can be obtained. The specific surface area of porous TiO 2 /fly-ash composite particles reaches 174.8 m 2 /g. HRTEM and XRD results suggested that the TiO 2 prepared was a single-crystalline structure featuring the (110) plane, but the plane had some structural defects for being bended and interrupted. Results of photocatalytic degradation of Rhodamine B showed that the catalytic activity of 1-D porous TiO 2 was higher than that without a porous structure. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to design a current transformer model based on the principle of B-dot. It can reflect the change of transmission line current and meet the requirement of automation and intelligence for current measurement in power system.Design/methodology/approach In this paper, a new type of current transformer is designed on the principle of B-dot, which has the structure of the inverse series of planar air core coils and the form of printed circuit board (PCB). With this structure, the current transformers can induce magnetic field quite well. The finite element simulation for the current transformer with n layers structure is conducted in the Maxwell, which help to optimize the design of the current transformer.Findings By setting up the experimental platform, the experiment of the current transformer is carried out. The results of the test show that the measurement accuracy can satisfy the requirement of measurement. Besides, the new current transformer has good transient characteristics and can meet the needs of the development of smart grid.Originality value The new type of current transformer is based on the principle of B-dot, which is designed with a new type of non-contact PCB hollow coil current transformer. It has no iron core, no ferromagnetic effect and the phenomenon of ferromagnetic resonance. It has great progress in its insulation performance, volume and bandwidth response. In addition, the planar hollow coil of the inverse series structure can make the structure more accurate. [ABSTRACT FROM AUTHOR]

In this work, charge-transfer mechanism of surface-enhanced resonance Raman scattering (SERRS) spectroscopy of pyrazine absorbed on Ac@Au7 clusters is theoretically investigated, and the coupling effect between the nanoparticles is especially concerned. First, the contributions of coupling effect to surface-enhanced Raman scattering (SERS) are compared between the ground-state nanoparticles. Second, the visualization of charge transfer provides evidence for the coupling effect on the charge-transfer enhancement mechanism of SERRS spectroscopy. The theoretical results show that the coupling effect on charge-transfer mechanism of SERRS can significantly enhance the intensity of SERS spectra up to about 6 × 105 times. The different coupling ways not only result in different degree of charge transfer on electronic transitions, but also cause different intensity of charge-transfer absorption peaks. Both of them strongly influence the enhancement of charge-transfer mechanism of SERRS. This study promotes the understanding of charge-transfer enhancement mechanism of SERRS for ultrasensitive Raman spectral analysis at nanoscale. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the design of three-phase D-dot voltage sensor based on electric field coupling, both effects of both the adjacent phase electric fields and distribution parameters on measurement should be taken into consideration. This paper builds a simulation model and a physical measuring system of a three-phase sensor, measures the effect of the distribution parameters by the simulation model, and finally finds the transfer function between the input and output voltage signals of the circuit. The measured voltage waveforms and parameters can be reflected by the physical measuring system. Our results provide a theoretical basis for the design of a three-phase D-dot voltage sensor. And the measuring system can achieve multipoint synchronous acquisition and ensure less distortion. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Vacuolar-type H-ATPase (V-ATPase), a multi-subunit endomembrane proton pump, plays an important role in plant growth and response to environmental stresses. In the present study, transgenic tobacco that overexpressed the V-ATPase c subunit gene from Iris lactea ( IrlVHA- c) was used to determine the function of IrlVHA- c. Quantitative PCR analysis showed that IrlVHA- c expression was induced by salt stress in I. lactea roots and leaves. Subcellular localization of green fluorescent protein (GFP) as marker combined with FM4-64 staining showed that the IrlVHA-c-GFP was localized to the endosomal compartment in tobacco cells. Compared with the wild-type, the IrlVHA- c transgenic tobacco plants exhibited greater seed germination rates, root length, fresh weight, and higher relative water content (RWC) of leaves under salt stress. Furthermore, the IrlVHA- c transgenic tobacco leaves have lower stomatal densities and larger stomatal apertures than wild-type. Under salt stress, superoxide dismutase (SOD) activity in the transgenic tobacco was significantly enhanced. Moreover, the level of malondialdehyde (MDA) in the transgenic tobacco was significantly lower than that in wild-type plants under salt stress. Taken together, these results suggested that the IrlVHA-c plays an important role in salt tolerance in transgenic tobacco by influencing stomatal movement and physiological changes. [ABSTRACT FROM AUTHOR]

• Blue-edge area vegetation index （BEAVI） improves the estimation ability. • Multi-angle combined vegetation index improves prediction accuracy. • Estimation models can be used for interannual testing. Rapid, non-destructive, and accurate monitoring is of great significance for determining crop nitrogen status and improving nitrogen fertilizer management. Multiple angle spectral data contains comprehensive and abundant information of crop canopy. In this study, the spectral data of cotton leaves at different leaf inclination angles (0°, 15°, 30°, and 45°) were collected using hyperspectral imaging technology at the seedling stage, bud stage, flowering stage, and boll-forming stage of cotton from 2018 to 2020, and indoor determination of cotton leaf nitrogen concentration (LNC) was conducted simultaneously. Based on the spectral features in blue edge and green edge regions, a new multi-angle blue-edge absorption vegetation index (MBEAVI) was constructed. Then, the MBEAVI and 16 vegetation indices (VI) reported in previous studies were constructed using single-angle and multi-angle spectral data of 2018 (320 sets) and 2019 (320 sets), and the inter-annual test was conducted with the data of 2020 (320 sets). The results showed that the VI models based on multi-angle spectral data (multi-angle models) had higher accuracy than the models based on single-angle spectral data (single-angle models). Among single-angle models, the model based on the optimized red edge absorption index (OREA) had the highest accuracy in cotton LNC estimation, with R2 of 0.735. However, the accuracy of multi-angle model, MBEAVI, was significantly higher than that of the OREA model, with R2 of 0.812. Besides, the R2 of the MBEAVI model reached 0.789 in the inter-annual test. Therefore, the MBEAVI model based on multi-angle spectral data had a higher accuracy and stability in predicting cotton LNC compared with the single-angle models. This study provides theoretical support for improving the accuracy of monitoring cotton nitrogen status by using multi-angle hyperspectral data. [ABSTRACT FROM AUTHOR]

Cuticular wax plays a role in plant responses to environmental stresses. To understand the contribution of cuticular wax to plant responses to low-temperature stress, the morphological and physiological responses of a Dianthus spiculifolius high-wax (HW) mutant and wild type (WT) were compared. Under low-temperature stress (0 and −10 °C), HW plants showed a lower mortality rate and electrolyte leakage (El) than that WT plants. In plants treated with low-temperature stress (0 and −10 °C), HW mutant leaves exhibited higher soluble sugar and free proline contents and lower malondialdehyde contents than those WT leaves. The photosynthetic capacity, net photosynthetic rate, stomatal conductance, and maximal photochemical efficiency of photosystem II in HW mutant leaves were the least inhibited by low temperature than those in WT leaves. The dewaxing experiments showed no significant difference in the phenotype and El between the dewaxed-treated HW mutant and WT leaves under low-temperatures stress, indicating that cuticular wax causes differences in resistance to low-temperatures between HW and WT. Principal component analysis and the membership function value of the physiological data showed that the average membership value of the HW mutant was greater than that in WT. In general, the results indicated that high cuticular wax contributes positively to the response to low-temperature stress by D. spiculifolius. [ABSTRACT FROM AUTHOR]

The mechanical behaviour of asphalt concrete is highly dependent on traffic loadings and environment conditions. Its compressive strength is sensitive to strain rate, temperature, as well as confining pressure. The influence of the confining pressure becomes more significant during the summer season due to the decrease of the viscosity of the bituminous binder which makes that the asphalt material tends to react more like an unbound granular material. This paper presents the results of an investigation into the effect of strain rate, temperature and confinement as determined on two different asphalt mixtures being dense and porous asphalt concrete. The results showed that the compressive strength and stiffness increased with a decreasing temperature, an increasing loading rate, and increasing confinement. The failure strength results of DAC in the I 1 - J 2 space show a nonlinear failure envelope while the results of PAC show properties similar to frictional granular material. The investigation has shown that the critical failure envelope of DAC highly depends on the strain rate which is hardly the case for PAC. [ABSTRACT FROM AUTHOR]

Plasmon-driven chemical reaction of 4-nitrobenzenethiol (4-NBT) dimerizing to p,p′-dimercaptoazobenzene (DMAB) has been successfully monitored under different pH solutions. The experimental results indicated that the chemical reactions were dependent on the pH values, and they proceeded more completely under acidic conditions than those under neutral and alkaline conditions. Furthermore, the rate of the chemical reactions was effectively controlled by exposure time and incident laser power. The stable pH dependence demonstrated the plasmon-driven chemical reactions of 4-NBT to DMAB are sensitive to the surrounding environment, and have wider applications. [ABSTRACT FROM AUTHOR]

The propagating surface plasmons on Ag nanowires (NW) have been investigated for over 10 years and which were interpreted with basic modes combining and hybridisation. Since the high confinement of the electromagnetic energy, the Ag NW-based surface plasmonics have been considered as one of the most potential ways to construct next-generation devices working with the light to overcome the speed limit of electronics. A lot of basic plasmonic NW components have already been developed. In this review paper, we focus on NW plasmonic waveguides based on the principles of propagating plasmon, plasmonic components and devices. The fundamental mechanism, the excitation, the propagation and the emission are discussed in detail. Based on these properties, we introduced their applications in nanophotonic devices. [ABSTRACT FROM AUTHOR]

Online transformer monitoring and protective relaying require voltage sensors with fast response and high precision. Traditional devices, such as resistive and capacitive dividers, have disadvantages in measuring transient voltage, e.g., oscillation, narrow bandwidth, and large size. This paper introduces a new D-dot probe for transient measurement. The difference input circuit structure is presented on the basis of the operating principle of the D-dot probe. Paralleled multiple electrodes are applied to gain the mutual capacitance value of the probe to achieve a large divide ratio and make the probe work in a self-integrating mode. Pspice simulation is conducted to find a way to minimize probe error. The probe is manufactured into printed circuit boards (PCB). The steady state linearity and transient response of the probe are tested. Results show that the probe has fast response and broad bandwidth. [ABSTRACT FROM AUTHOR]

This research used hollow glass microspheres (HGMS) as carrier and polystyrene (PSt) as template. PSt was loaded on HGMS surface through the modification by silane coupler. Next, amorphous titanium dioxide (TiO 2 ) produced through tetrabutyl titanate (TBT) hydrolysis precipitated on PSt surface, forming HGMS/PSt/TiO 2 particles. Lastly, using the calcinations method, this research obtained anatase TiO 2 , eliminated PSt, and ultimately acquired composite particles with hollow TiO 2 loaded on HGMS surface (HGMSHT). SEM results presented that hollow TiO 2 was compact on HGMS surface and a multilayer network structure was formed. The specific surface area of HGMSHT particles was 26 m 2 /g, which was much larger than that of HGMS/TiO 2 (HGMST) composite particles (5.6 m 2 /g) through direct TBT hydrolysis. Results of catalytic degradation experiment with Rhodamine B and phenol under UV light and sunlight demonstrated that due to larger TiO 2 load capacity and specific surface area, the catalytic activity of HGMSHT composite particles was significantly more desirable than that of HGMST, and the catalyst presented satisfactory stability. [ABSTRACT FROM AUTHOR]

Solar radiation in the band of 240-280 nm is absorbed by the ozone layer in the atmosphere, and corona discharges from high-voltage apparatus emit in air mainly in the 230-405 nm range of ultraviolet (UV), so the band of 240-280 nm is called UV Solar Blind Band. When the insulators in a string deteriorate or are contaminated, the voltage distribution along the string will change, which causes the electric fields in the vicinity of insulators change and corona discharge intensifies. An UV pulse detection method to check the conditions of insulators is presented based on detecting the UV pulse among the corona discharge, then it can be confirmed that whether there exist faulty insulators and whether the surface contamination of insulators is severe for the safe operation of power systems. An UV-I Insulator Detector has been developed, and both laboratory tests and field tests have been carried out which demonstrates the practical viability of UV-I Insulator Detector for online monitoring. [ABSTRACT FROM AUTHOR]

In this work, we used multi-scale computational simulation methods combined with density functional theory (DFT) and finite element analysis (FEA) in order to study the optical properties of substitutional doped aluminium nitride (AlN). There was strong surface plasmon resonance (SPR) in the near-infrared region of AlN substituted with different alkali metal doping configurations. The strongest electric field strength reached 109 V/m. There were local exciton and charge transfer exciton behaviours in some special doping configurations. These research results not only improve the application of multi-scale computational simulations in quantum surface plasmons, but also promote the application of AlN in the field of surface-enhanced linear and non-linear optical spectroscopy. [ABSTRACT FROM AUTHOR]

The electronic states of the twist bilayer graphene (TBG) moiré superlattice are usually regulated by the rotation angle, applied electric field, applied magnetic field, carrier concentration and applied stress, and thus exhibit novel physical properties. Squeezing, that is, applying vertical compressive stress to the graphene layers, has profound significance in regulating the photoelectric properties of the moiré superlattice and constructing optical nanodevices. This paper presents the photoelectric properties of a TBG moiré superlattice with a twist angle of 13.17° and tunability under vertical stress. Interlayer distance decreases nonlinearly with compressive stress from 0 to 10 GPa, giving rise to weakened interlayer coupling compared to a Bernal-stacked graphene bilayer and an enhanced repulsive effect between the layers. The calculated Bloch wave functions show a strong dependence on stress. With the increase in stress, the band gaps of the system present a nonlinear increase, which induces and enhances the interlayer charge transfer and leads to the redshift of the absorption spectrum of the moiré superlattice system. By analyzing the differences in the Bloch wave function and charge density differences, we explain the nature of the physical mechanism of photoelectric property change in a stress-regulated twist superlattice system. This study provides a theoretical basis for the identification of piezoelectric properties and the stress regulation of photoelectric devices based on TBG, and also provides a feasible method for regulating the performance of TBG. [ABSTRACT FROM AUTHOR]

Defects, such as twisting, in fused aromatic hydrocarbons disrupt the plane of the π orbital. The twisted structure induces an electric field in the system and affects the spectra. In this work, theoretical studies show that the intramolecular electric field within a distinctly twisted structure is larger than that of other molecules. In addition, the spectral study shows that the degree of charge transfer and the magnetic transition dipole in the electrostatic potential extremum region of the molecular electric field were significantly improved, which affected the optical absorption and chiral optical behavior of the molecule. The discovery of this theoretical regulation law will provide a solid foundation for the electric-field-induced regulation of optical properties and will promote the precise design and synthesis of optoelectronic molecules with inner electric fields. [ABSTRACT FROM AUTHOR]

Highlights: [•] An evident synergistic effect was observed in the degradation of the dye K-2BP using SJC/Fenton process. [•] The effects of various operating parameters on the degradation of K-2BP were investigated. [•] The degradation mechanism of the dye K-2BP was discussed. [ABSTRACT FROM AUTHOR]

Based on the relationship between electrical equipment discharge and ultraviolet radiation, this paper proposed the use of UV pulse method to detect switchgear arcing faults. Switchgear protection system based on this new technique detects arcing faults by analyzing the ultraviolet produced by electric arc. This technique was implemented and tested in laboratory, and the performance of the protection module was verified: it is capable of calculating the number of UV pulses quickly and precisely, which indicates the intensity of fault arc, and therefore it can be applied to arcing faults protection system for detecting faults. [ABSTRACT FROM AUTHOR]

• A calculation method for electromagnetic fields of thermal power plant is proposed. • The presence of the hollow overhead trays influences magnetic fields in PC. • The soil resistivity influences the magnetic fields in PC. • The design of the spatial layouts of the sensitive devices has been optimized. Lightning strikes thermal power plant will affect the normal operation of sensitive devices. However, due to the complex structure of thermal power plant, the calculation of electromagnetic field distribution is not accurate, and there is a lack of lightning protection specifications for low-voltage systems. Firstly, taking a thermal power plant in China as the object, an electromagnetic model of the low-voltage system including large irregular grounding grids, transformers, distribution lines, overhead cable trays, and external lightning protection systems is established, and a calculation method suitable for spatial electromagnetic fields of the complex model of thermal power plant is proposed. Secondly, the method is applied to the calculation of the maximum value of the magnetic fields at different layers, and the results show that the calculation accuracy is greatly improved. Finally, a method for optimizing the spatial layouts of sensitive devices in thermal power plant is proposed. This article provides data support for the design specifications and standards for lightning protection of low-voltage systems in thermal power plant. The spatial layouts of sensitive devices are optimized to achieve the purpose of rational use of building spatial and saving engineering costs. [ABSTRACT FROM AUTHOR]