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Hybrid excitons, characterized by their strong oscillation strength and long lifetimes, hold great potential as information carriers in semiconductors. They offer promising applications in exciton‐based devices and circuits. MoSe2/WS2 heterostructures represent an ideal platform for studying hybrid excitons, but how to regulate the exciton lifetime has not yet been explored. In this study, layer hybridization is modulated by applying electric fields parallel or antiparallel to the dipole moment, enabling us to regulate the exciton lifetime from 1.36 to 4.60 ns. Furthermore, the time‐resolved photoluminescence decay traces are measured at different excitation power. A hybrid exciton annihilation rate of 8.9 × 10−4 cm2 s−1 is obtained by fitting. This work reveals the effects of electric fields and excitation power on the lifetime of hybrid excitons in MoSe2/WS2 1.5° moiré heterostructures, which play important roles in high photoluminescence quantum yield optoelectronic devices based on transition‐metal dichalcogenides heterostructures. [ABSTRACT FROM AUTHOR]

An early warning method based on Session Initiation Protocol (SIP) concept for generator set electrical control abnormal response is proposed. The first is to clean the electrical data of the generator set by SIP. Using Supervisory Control and Data Acquisition (SCADA) and Generalized Linear Models (GLM) algorithm, a linear model is constructed to analyze the electrical control of generating units. Using the Autoregressive Integrated Moving Average Model (ARIMA), an abnormal response early warning model for electrical control of generating units is established. BP neural network is used to train the abnormal response data of the generator set electrical control. According to the current response data, the model prediction is realized, and the early warning of the abnormal response of the generator set electrical control is effectively realized. The simulation results show that the proposed method can effectively reduce the early‐warning error, false alarm rate, and early‐warning delay of generator electrical control abnormal response. [ABSTRACT FROM AUTHOR]

Abstract Hybrid excitons, characterized by their strong oscillation strength and long lifetimes, hold great potential as information carriers in semiconductors. They offer promising applications in exciton‐based devices and circuits. MoSe2/WS2 heterostructures represent an ideal platform for studying hybrid excitons, but how to regulate the exciton lifetime has not yet been explored. In this study, layer hybridization is modulated by applying electric fields parallel or antiparallel to the dipole moment, enabling us to regulate the exciton lifetime from 1.36 to 4.60 ns. Furthermore, the time‐resolved photoluminescence decay traces are measured at different excitation power. A hybrid exciton annihilation rate of 8.9 × 10−4 cm2 s−1 is obtained by fitting. This work reveals the effects of electric fields and excitation power on the lifetime of hybrid excitons in MoSe2/WS2 1.5° moiré heterostructures, which play important roles in high photoluminescence quantum yield optoelectronic devices based on transition‐metal dichalcogenides heterostructures.

The valley index is a promising degree of freedom for information processing in electronic devices. However, the researches on valley polarization are mainly focused on ferromagnetic order, which breaks the time reversal symmetry simultaneously. Here, a novel paradigm for achieving stacking order modulated anomalous valley Hall (AVH) effect is proposed in antiferromagnetic monolayers. The paradigm involves the introduction and reversal of nonuniform potentials by modulating the position of substrate, to break the combined symmetry of spatial inversion and time reversal (PT symmetry) and achieve stacking-dependent valley spin splitting. Based on first-principles calculations, we discover spontaneous valley polarization in antiferromagnetic Cr2CH2 MXene and stacking-dependent valley spin splitting in Cr2CH2/Sc2CO2 heterostructure. Furthermore, switching the ferroelectric polarization of monolayer Sc2CO2 results in a semiconductor-metal transition in Cr2CH2/Sc2CO2, accompanied by the disappearance of valley physics. Our findings provide an alternative way to develop controllable valleytronics devices based on antiferromagnetic monolayers.

Abstract Spatial manipulation of excitonic quasiparticles, such as neutral excitons, charged excitons, and interlayer excitons, in two-dimensional semiconductors offers unique capabilities for a broad range of optoelectronic applications, encompassing photovoltaics, exciton-integrated circuits, and quantum light-emitting systems. Nonetheless, their practical implementation is significantly restricted by the absence of electrical controllability for neutral excitons, short lifetime of charged excitons, and low exciton funneling efficiency at room temperature, which remain a challenge in exciton transport. In this comprehensive review, we present the latest advancements in controlling exciton currents by harnessing the advanced techniques and the unique properties of various excitonic quasiparticles. We primarily focus on four distinct control parameters inducing the exciton current: electric fields, strain gradients, surface plasmon polaritons, and photonic cavities. For each approach, the underlying principles are introduced in conjunction with its progression through recent studies, gradually expanding their accessibility, efficiency, and functionality. Finally, we outline the prevailing challenges to fully harness the potential of excitonic quasiparticles and implement practical exciton-based optoelectronic devices.

The two‐dimensional (2D) materials InX (X = O, Se), experimentally available thus far, can become a ferromagnetic half metal under hole doping, though the charge neutral states of them are nonmagnetic semiconductors. Based on such an electronic characteristic, a theoretical model of magnetic tunnel junction (MTJ) is proposed composed only of one of the 2D InX. In doing so, the two semi‐infinite pieces of 2D InX in the half‐metallic state is assumed as the opposite electrodes which are separated by a strip of the same material but in its nonmagnetic state. Owing to the 2D nature of InX, the half metal electrodes of the InX device induced by hole doping can be achieved by using split gating technique. The numerical simulations identify a proper hole doping concentration, at which 100% tunneling magnetoresistance (TMR) ratios can be realized, accompanying an appreciable conductance of majority spin electron under parallel magnetization configuration. Under a finite bias voltage, the TMR ratio remains high. Therefore, the proposed device model is an ideal candidate for future spintronics applications. It enables electrical control of TMR and circumvents the detriment of hetero‐interface disorder inevitable in conventional MTJs. [ABSTRACT FROM AUTHOR]

Spatial manipulation of excitonic quasiparticles, such as neutral excitons, charged excitons, and interlayer excitons, in two-dimensional semiconductors offers unique capabilities for a broad range of optoelectronic applications, encompassing photovoltaics, exciton-integrated circuits, and quantum light-emitting systems. Nonetheless, their practical implementation is significantly restricted by the absence of electrical controllability for neutral excitons, short lifetime of charged excitons, and low exciton funneling efficiency at room temperature, which remain a challenge in exciton transport. In this comprehensive review, we present the latest advancements in controlling exciton currents by harnessing the advanced techniques and the unique properties of various excitonic quasiparticles. We primarily focus on four distinct control parameters inducing the exciton current: electric fields, strain gradients, surface plasmon polaritons, and photonic cavities. For each approach, the underlying principles are introduced in conjunction with its progression through recent studies, gradually expanding their accessibility, efficiency, and functionality. Finally, we outline the prevailing challenges to fully harness the potential of excitonic quasiparticles and implement practical exciton-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Electromagnetic filtering is essential for emerging integrated photonic technologies and widely adaptable processing of high‐bandwidth signals. The conventional electro‐optic modulator‐based photonic approach for signal filtering at microwave frequencies cannot be implemented at terahertz (THz) frequencies due to the unavailability of the THz signal‐driven optical modulator. Here, an electrically tunable on‐chip THz photonic notch filter based on the topologically protected valley hall waveguide‐cavity platform is demonstrated. The device shows a significantly large notch suppression depth of more than 20 dB with a return loss of 13 dB in the entire tuning range of notch frequency. The feedback control circuit enables precise control of the notch frequency shift with a minimum step size of 7 MHz. This work extends the application of topological photonic crystals in developing THz‐integrated photonic devices for transformative technologies, including sixth‐generation (6G) communication and high‐resolution spectral sensing. [ABSTRACT FROM AUTHOR]

Thermal fluctuations in two-dimensional (2D) isotropy systems at non-zero finite temperatures can destroy the long-range (LR) magnetic order due to the mechanisms addressed in the Mermin-Wanger theory. However, the magnetic anisotropy related to spin–orbit coupling (SOC) may stabilize magnetic order in 2D systems. Very recently, 2D FexGeTe2 (3 ≤ x ≤ 7) with a high Curie temperature (TC) has not only undergone significant developments in terms of synthetic methods and the control of ferromagnetism (FM), but is also being actively explored for applications in various devices. In this review, we introduce six experimental methods, ten ferromagnetic modulation strategies, and four spintronic devices for 2D FexGeTe2 materials. In summary, we outline the challenges and potential research directions in this field. [ABSTRACT FROM AUTHOR]

Exceptional points (EPs) are degenerate singularities in a non-Hermitian system that can be induced by controlling the interaction between resonant photonic modes. EPs can enable unusual optical phenomena and significantly enhance the optical sensitivity under small perturbations. However, most studies thus far have been limited to static photonic structures. In this study, we propose and experimentally demonstrate electrically addressable EP in a plasmonic structure. Inspired by optical microcavity studies, we employ a localized spoof plasmon structure that supports circulating plasmonic modes in compact single-resonator geometry. The plasmonic modes are perturbed by an angled metal line, and the interaction between the plasmonic modes is electrically controlled using a varactor. Continuous electrical tuning of the varactor capacitance facilitates simultaneous coalescence of the real and imaginary parts of the eigenfrequency, allowing the direct addressing of EPs. We first investigate the eigenmodes and their coupling in localized plasmonic structures using numerical simulations. We then present experimentally measured spectra that manifest the coalescence of the two resonant modes in both the resonance frequency and linewidth. Electrically addressable EPs in compact plasmonic structures may provide exciting opportunities for highly functional and tunable elements in integrated device platforms.

Abstract Stacking of monolayer 2D transition metal dichalcogenides (TMDs) into van der Waals heterostructures can enable the formation of interlayer excitons (IXs) with long lifetimes and permanent out‐of‐plane electric dipoles, allowing them to propagate over long distances. While early studies on TMD heterobilayrs show efficient electrical control of excitonic transport of IXs by creating different energy potentials, the electrically controllable exciton states and associated spatial migration remain elusive. Here, an electrical control of exciton diffusion through the change of exciton states between charged IXs (CIXs) and charged intralayer excitons is reported. The repulsive dipolar interaction of IXs accounts for the growing exciton cloud size and increasing diffusion length in the power‐dependent PL study. More importantly, the electrically tunable spatial exciton distribution is demonstrated by switching the exciton states, which shows a 1.5‐fold change in diffusion length and an order of magnitude increase in lifetime from charged intralayer excitons to CIXs. The electrical control of exciton states and the relevant diffusion dynamics provide another knob to study the interplay between propagation and many‐body interactions for the development of excitonic devices.

The electrical modulation of the functionality of matter is of significant interest in physics and multifunctional tunable electronic device applications. Here, new dielectric materials with nanogranular structures comprised of nano‐sized Co granular metals dispersed in a Mg‐fluoride‐based dielectric matrix are explored. The dielectric relaxation frequency (fr), which represents a sharp decrease in dielectric permittivity in dielectrics, can be tuned by a DC electric field (E). As E increases, the position of fr first shifts to the low‐frequency side and then to the high‐frequency side, achieving a tunable fr in a certain frequency range. The ability to electrically modulate the relaxation frequency may help construct novel tunable frequency filters. The dielectric properties are theoretically examined based on the asymmetric electron tunnelling model that considers the size difference of granular pairs, offering an insightful understanding of the structure‐property relationship in disordered granular solids. [ABSTRACT FROM AUTHOR]

This article proposes a fault component location method based on graph theory and analyzes the properties of the elements in the fault judgment matrix. We can use the exclusive OR algorithm to determine the faulty section. On this basis, the realization model and algorithm essence of the optimal test set is given. At the same time, we propose an optimal test set design for circuit fault diagnosis based on graph theory. Finally, the realization of the article verified that the method adapts to the flexible operation mode of the active distribution network structure and can accurately determine the fault section.

Properties of plasmons in graphene can be controlled electrically. My research colleagues and I have used this feature to verify that plasmons of desired frequencies can be excited in electrically specified regions. This technology can be applied to plasmonic devices such as waveguides and switches. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The electrical modulation of the functionality of matter is of significant interest in physics and multifunctional tunable electronic device applications. Here, new dielectric materials with nanogranular structures comprised of nano‐sized Co granular metals dispersed in a Mg‐fluoride‐based dielectric matrix are explored. The dielectric relaxation frequency (fr), which represents a sharp decrease in dielectric permittivity in dielectrics, can be tuned by a DC electric field (E). As E increases, the position of fr first shifts to the low‐frequency side and then to the high‐frequency side, achieving a tunable fr in a certain frequency range. The ability to electrically modulate the relaxation frequency may help construct novel tunable frequency filters. The dielectric properties are theoretically examined based on the asymmetric electron tunnelling model that considers the size difference of granular pairs, offering an insightful understanding of the structure‐property relationship in disordered granular solids.

Thermal fluctuations in two-dimensional (2D) isotropy systems at non-zero finite temperatures can destroy the long-range (LR) magnetic order due to the mechanisms addressed in the Mermin-Wanger theory. However, the magnetic anisotropy related to spin–orbit coupling (SOC) may stabilize magnetic order in 2D systems. Very recently, 2D FexGeTe2 (3 ≤ x ≤ 7) with a high Curie temperature (TC) has not only undergone significant developments in terms of synthetic methods and the control of ferromagnetism (FM), but is also being actively explored for applications in various devices. In this review, we introduce six experimental methods, ten ferromagnetic modulation strategies, and four spintronic devices for 2D FexGeTe2 materials. In summary, we outline the challenges and potential research directions in this field.

Hybrid excitons, characterized by their strong oscillation strength and long lifetimes, hold great potential as information carriers in semiconductors. They offer promising applications in exciton-based devices and circuits. MoSe 2 /WS 2 heterostructures represent an ideal platform for studying hybrid excitons, but how to regulate the exciton lifetime has not yet been explored. In this study, layer hybridization is modulated by applying electric fields parallel or antiparallel to the dipole moment, enabling us to regulate the exciton lifetime from 1.36 to 4.60 ns. Furthermore, the time-resolved photoluminescence decay traces are measured at different excitation power. A hybrid exciton annihilation rate of 8.9 × 10 -4  cm 2  s -1 is obtained by fitting. This work reveals the effects of electric fields and excitation power on the lifetime of hybrid excitons in MoSe 2 /WS 2 1.5° moiré heterostructures, which play important roles in high photoluminescence quantum yield optoelectronic devices based on transition-metal dichalcogenides heterostructures., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

This paper presents an electrical backlash control method based on a novel variable tooth thickness involute gear pair (VTTIGP) through acceleration judgment. First, the principle, characteristics and theoretical tooth surface equation of the novel type of variable tooth thickness involute gear (VTTIG) are proposed. Compared with the traditional variable tooth thickness gear (VTTG), each transverse of the novel type of VTTIG has the same tooth root circle and the addendum circle. Therefore, there will be no interference caused by the excessive axial relative movement distance between the gear pairs when eliminating the backlash. The theoretical calculation equation of no-load transmission error (TE) and time-varying backlash for a dual-eccentric novel type of VTTIGP are deduced. Second, using the theoretical backlash equation and the eccentricities and the initial phases obtained through the experimental TE curve obtained with angular displacement sensors and the developed TE equation, the continuous backlash curve of the gear pair is obtained. Based on the RecurDyn software and its Colink control module, the co-simulation model of the novel type of VTTIGP and its backlash control system is used to explore the electrical backlash control method through acceleration judgment in the case of time-varying backlash. Finally, using angular displacement sensors and linear actuators, the experimental study on the anti-backlash control with different reversed positions under different input speeds is carried out, demonstrating that this novel electrical anti-backlash control method is effective. [ABSTRACT FROM AUTHOR]

We propose an F-band phase shifter based on the nematic liquid crystals (NLCs). The proposed phase shifter is formed by a voltage-controlled cavity through introducing an NLC layer between a dipole structure array and a metal floor. Under the action of electric field, the orientation of the NLC molecules will be deflected. We adjust the resonant frequency and phase of the reflected electromagnetic (EM) wave by tuning the permittivity. The transmission characteristics and the LC parameters are calculated and analyzed for EM waves within the frequency range from 85 to 115 GHz. The LC-based device with a $30\times 30$ array of two parallel unequal dipoles is printed on a quartz substrate, with 4 cm $\times {4}$ cm area and $490~\mu \text{m}$ thickness. The experimental results show that phase shift of zero to 350.7° is achieved at 104.2 GHz by changing the applied bias voltage on the LC layer from 0 to 20 V. Considering the anisotropy and inhomogeneity of the LC, an improved electrification model is established and compared with the test results. The proposed phase shifter is expected to find several applications in millimeter wave and terahertz reconfigurable antenna systems.

In the existing soybean breeding and planting machinery, the power source of the metering device adopts the ground wheel transmission method mostly. However, this power transmission method is likely to cause slippage during the planting operation, which will cause problems such as the increase of the missed seeding index and the increase of the coefficient of plant spacing. It is not conducive for scientific researchers to carry out breeding operations. Aiming at this problem, an electronically controlled soybean seeding system is designed, and the power of the seed metering device is derived from the motor. In order to improve the control accuracy of the electronically controlled seeding system, the precise control of the soybean seeding rate is finally realized. The electric drive soybean seeding system adopts closed-loop control, the motor model of the electric drive seeding system is established, and the transfer function of the motor is obtained. PID control based on a genetic algorithm is adopted, and the corresponding parameters are substituted into the control system simulation model established in MATLAB/SIMULINK. Field verification tests have been carried out on the conventional fuzzy PID control system and the electric drive soybean planter of the fuzzy PID control system based on a genetic algorithm. The result showed that the average of the repeat-seeding parameter is 1.30% better than the average of conventional seeding system (1.40%), the average of the miss-seeding parameter is 1.08% better than the average of conventional seeding system (2.09%) and the average of row-spacing variation parameter is 2.79% better than the average of conventional seeding system (2.34%). In conclusion, the new seeding system is robust obviously. Field trial results show that seeding with Genetic Algorithm Fuzzy control is better. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, we present a study of the equivalent dielectric constant of two nematic liquid crystals (LCs) with different thicknesses, in the region from 90 to 140 GHz. The equivalent dielectric constant of the LCs was measured using a frequency selective surface (FSS). The LC-based tunable FSS with 22 × 25 unit cells was printed on a quartz substrate with an area of 4 × 4 cm2 and a thickness of 480 µm; the LC layer with thicknesses ranging from 30 to 100 µm acted as a substrate. The FSS featured a maximum frequency-shifting range of 8.15 GHz and 30 µm-thick LC layers with mutually orthogonal rubbing directions were deposited on it. The results show that the initial equivalent dielectric constant of the LC layer increased with the LC layer thickness, while the saturation-equivalent dielectric constant remained almost constant. This work provides LC parameters that can be useful for the design of LC-based devices in the millimeter and terahertz ranges.

Electrical tuning of bandwidth is critical for microelectromechanical system (MEMS) resonator‐based narrowband filters especially at ultra‐high frequency ranges and beyond. The resonance frequency of MEMS resonators is highly susceptible to fabrication process uncertainties and very small fabrication variations could result in significant shift in their resonance frequency. Although, disk resonators are the most acceptable candidates for implementing of resonators at GHz frequencies, according to their high stiffness, electrical tuning of these resonators and consequently the resulting filters is almost impossible. This study presents a novel tuning method for low velocity through anchor coupled MEMS radial contour mode disk resonators based on the coupling beam's stiffness tuning using the piezoelectric effect. As the results of this method, high bandwidth tuning ratio as 1:1.25 is achieved due to changing the tuning DC voltage from 0 to 20 V. This impressive result for a narrowband filter with 450 kHz of bandwidth is achieved due to changing the stiffness of low stiff coupling beam which is much easier to control in comparison with extremely high stiffness disk resonators. Various simulation results, as well as analytical works, verify the proposed approach. [ABSTRACT FROM AUTHOR]

Time of flight mass separator is the major component of the quadrupole time of flight mass spectrometry (Q-TOF MS). Time of flight mass spectrometer (TOF MS) measures mass spectra by using the principle that different mass charge ratio ions have different flight times for same distance within a free flight field in vacuum. TOF MS has the advantages of microsecond-level fast detection speed, high ion transmission rate, high sensitivity and precision. Theoretically, there is no upper quality limitation which means large quality detection range. With its resolution increasing and these advantages, TOF MS is now widely used. The core factor affecting TOF MS resolution is that the initial kinetic energy and the initial position of ion are easily dispersed. For mass spectrometers, ion optics and electrodepowered systems form the electric field that controls ions. Vacuum provides the environment needed for operation. Signal detection systems are responsible for the measurement and acquisition of ion signals, while computer software and control systems are key to integrating all parts. This review started with a theoretical calculation of the time of flight mass separator, deduced an ideal formula, and provided a computer optimization to determine the required mechanical and electrical parameters. Based on the development experience in author’s laboratory yearly, the review would focus on the ion optics and related electronic control technique of TOF MS, such as vertical ion beam introduction, grid-connected fields, reflectron, and etc. The ion optical technique involved the precision manufacture, and the assembly of acceleration field and reflection field. The key to the success of a time of flight mass separator was the machining precision. A good optical system should provide the ideal quality resolution. The mechanical position and shape of electrodes of the ion optical system were physically fixed after design. The other boundary condition for controlling the electric field of ion motion depended on the voltage applied to the electrodes. These voltage values were provided and controlled by the circuit power supply system. The two major components of the circuit part involved in the mass spectrometer were the signal acquisition system and the electrode power supply system, but they were not completely independent. The signal collected by the signal acquisition system should be correlated according to the timing of the electrode power supply. Finally, the computer software could convert a time-related information recorded on the acquisition card into the mass to charge ratio information of ions through the corresponding formula. [ABSTRACT FROM AUTHOR]

• A non-volatile mediation of the ferromagnetic resonance field and linewidth by applying the electric field in the film. • The asymmetric butterfly-like H r -E curves demonstrate the non-volatile mediation dominated by the strain effect. • The origin of four-fold anisotropy FMR linewidth is attributed to the two-magnon scattering induced by oblique sputtering. In this study, we present a novel approach to control the microwave properties of a Co/Ru/FeNi film, characterized by strong antiferromagnetic coupling and in plane uniaxial anisotropy. The film is fabricated on a Pb(Mg 1/3 Nb 2/3)O 3 -PbTiO 3 (PMN-PT) ferroelectric substrate using the magnetron oblique sputtering. Our experimental results demonstrate a remarkable non-volatile mediation of the ferromagnetic resonance (FMR) field and linewidth by applying the perpendicular-bias electric field. The observed asymmetric butterfly curve indicates the existence of electric mediation dominated by strain effect. Moreover, we investigate the angular dependence of FMR under different electric field, which reveals changes in magnetic anisotropy including FMR field. Notably, the FMR linewidth exhibits a distinctive four-fold anisotropy. Through microstructure analysis of the film surface, we identify that the origin of this FMR linewidth anisotropy is attributed to the two-magnon scattering induced by the oblique sputtering. [ABSTRACT FROM AUTHOR]

• Droplets generation is depend on focused surface acoustic waves completely rather than flow shear. • by a simple tuning of the driving frequency and voltage of FSAW, droplets size can be precisely controlled. • A linear relationship between the droplet size and the applied driving voltage is presented. • The closer of frequency of driving signal to the resonance frequency, the smaller the droplets size. • FSAW-based microdroplet formation technique is applied to manufacturing microspheres. We demonstrate a novel microdroplets generation method by using focused surface acoustic waves (FSAW). The method differs from previous work in the mechanism and the geometry structure of the chip, which is depend on FSAW rather than flow shearing. The acoustic radiation force arising from FSAW acts on the oil-water interface, breaking up the water into microdroplets whose size can be controlled by tuning the driving voltage and frequency of FSAW. This approach overcomes the limitation of microchannel structure and capillary number of the traditional microfluidic droplets formation methods, which enables a fully electrical control of microdroplets size, with a good uniformity. Further, the FSAW-induced microdroplets are used as templates to prepare microgels with uniform size, offering a new platform for the design and synthesis of monodispersed functional microspheres. [ABSTRACT FROM AUTHOR]

We report the transient response of gliding microtubules on a virtual cathode. In vivo activities, microtubule-kinesin systems are known to act as motor proteins with respect to cell motility cytokinesis and cellular transport by hydrolyzing ATP molecules. With development of in vitro assays, motor proteins have been attracting much attention as a key component for highly efficient nano-transportation systems. The molecular functions based on structural states are affected by changing the ionic condition of the molecular functions and by changing the electrical field in solution because of electrical charges of the molecules. The virtual cathode, which was generated on the SiN display surface by a low energy electron beam, locally induced electrochemical reactions and electric field around the targeted molecules on the display surface, and then the gliding motions of the targeted microtubules were regulated. In this study, we demonstrated that the virtual cathode display temporally stops a selected gliding microtubule by only applying the virtual cathode to the microtubule. The pause mode of the microtubule was easily canceled by simply turning the virtual cathode off, and then the gliding motion was restarted. Image 1 • Virtual cathode could control pause and restart of gliding microtubles on kinesins. • The virtual cathode could target on pinpoint microtubles. • Pause of gliding motion of microtubles occurred at current density of 1.11–1.16 pA/μm2. [ABSTRACT FROM AUTHOR]

Aiming at the problems of time-consuming for laboring manual filling process of paraffin oil in the process of grease production, and difficulty in ensuring accuracy and real-time performance, an automatic filling device of paraffin oil that can automatically fill material, weigh and fill was studied, which based on the analysis of technological process and field layout. The mechanical structure of the device was made of aluminum profile as the base material, and the up-down distribution structure was adopted to integrate feeding, weighing and filling processes. PLC was adopted as the control system for electrical control, the structure of the control system was designed, the hardware composition of the control system to be raised. Based on PLC, the program of analog quantity information collection and communication with the weighing controller was compiled. The corresponding trapezoidal diagram and the configuration of man-machine interface were written. The results indicate that the device has the advantages of simple structure, smooth operation, high filling precision, greatly improves production automation. [ABSTRACT FROM AUTHOR]

Low-dimensional nanomaterials, such as one-dimensional (1D) nanomaterials and layered 2D materials, have exhibited significance for their respective unique electronic and optoelectronic properties. Here we show that a mixed-dimensional heterostructure with building blocks from multiple dimensions will present a synergistic effect on photodetection. A carbon nanotube (CNT)–WSe2–graphene photodetector is representative on this issue. Its spatial resolution can be electrically switched between highresolution mode (HRM) and low-resolution mode (LRM) revealed by scanning photocurrent microscopy (SPCM). The reconfigurable spatial resolution can be attributed to the asymmetric geometry and the gate-tunable Fermi levels of these low-dimensional materials. Significantly, an interference fringe with 334 nm in period was successfully discriminated by the device working at HRM, confirming the efficient electrical control. Electrical control of spatial resolution in CNT–WSe2–graphene devices reveals the potential of the mixed-dimensional architectures in future nanoelectronics and nano-optoelectronics. [ABSTRACT FROM AUTHOR]

Graphene has recently emerged as a viable platform for integrated optoelectronic and hybrid photonic devices because of its unique properties. The optical properties of graphene can be dynamically controlled by electrical voltage and have been used to modulate the plasmons in noble metal nanostructures. Graphene has also been shown to support highly confined intrinsic plasmons, with properties that can be tuned in the wavelength range of 2 μm to 100 μm. Here we review the recent development in graphene-plasmonic devices and identify some of the key challenges for practical applications of such hybrid devices.

Ionic contaminants such as Cr(VI) pose a challenge for water purification using membrane-based processes. However, existing membranes have low permeability and selectivity for Cr(VI). Therefore, in this study, we prepared an electrically controlled adsorptive membrane (ECAM-L) by coating a loose Cl - -doped polypyrrole layer on a carbon nanotube substrate, and we evaluated the performance of ECAM-L for Cr(VI) separation from water. We also used electrochemical quartz crystal microbalance measurements and molecular dynamics and density functional theory calculations to investigate the separation mechanisms. The adsorption and desorption of Cr(VI) could be modulated by varying the electrostatic interactions between ECAM-L and Cr(VI) via potential control, enabling the cyclic use of the ECAM-L without additional additives. Consequently, the oxidized ECAM-L showed high Cr(VI) removal performance (<50 μg/L) and treatment capacity (>3500 L/m 2 ) at a high water flux (283 L/m 2 /h), as well as reusability after the application of a potential. Our study demonstrates an efficient membrane design for water decontamination that can selectively separate Cr(VI) through a short electric stimulus.

By stacking different layers of two dimensional (2D) monolayer materials, the electronic properties of the 2D van der Waals (vdW) heterostructures can be tailored. However, the Schottky barrier formed between 2D semiconductor and metallic electrode has greatly limited the application of 2D semiconductor in nanoelectronic and optoelectronic devices. Herewith, we investigate the electronic properties of borophene/g-C 2 N vdW heterostructures by first-principles calculations. The results indicate that electronic structures of borophene and g-C 2 N are preserved in borophene/g-C 2 N vdW heterostructures. Meanwhile, upon the external electric field, a transition from the n -type Schottky contact to Ohmic contact is induced, and the carrier concentration between the borophene and g-C 2 N interfaces can be tuned. These results are expected to provide useful insight in the nanoelectronic and optoelectronic devices based on the borophene/g-C 2 N vdW heterostructures. [ABSTRACT FROM AUTHOR]

Equipment availability is necessary in the development of Agriculture mechanization. Crop thinning is one of the most important stages in row crop production which is laborious and costly. The objective of this project is design and construction of a row crop thinning machine. Four main system units are plant sensors, ground sensors, control and thinning platforms. In this machine the unwanted plants on the rows are randomly removed by employing a pneumatically system. A blade on a vertical arm with pendulum motion removes the plant from the rows. The machine control system consists of an arm and a blade which is activated by a double acting cylinder and equipped with a relay and a timer. The pneumatic cylinder is controlled via a solenoid valve. Laboratory tests were conducted to validate the machine performance. Some other preliminary tests also were performed for optimization of parameters such as cinematic index and cutting length of blades. The laboratory tests (totally 9 tests) were performed with a constant forward speed and three levels of plant density, using artificial plants. The data were analyzed using SPSS software. The results show that satisfactory performance of the machine is achieved when the plant density is moderate i.e. the thinning performance reduces with higher plant distance in the row. The other effective variable on machine performance is the adjustment of sensor sensitivity, which is used to distinguish between week and strong plants. In general the machine performance is sensitive to plant shape and morphology, plant distribution pattern in the field, growing stage of the plants, time of thinning and the effectiveness of previous weeding operations

Control of valley degree of freedom in monolayer transition-metal dichalcogenide (TMDC) has been realized by using optical pumping and magnetic fields. However, an electrical approach is missing and has potential for practical applications. In this paper, valley/ferroelectricity coupling is demonstrated for the first time in a monolayer WTe2/YMnO3 heterostructure. Tunable valley splitting by an electric field is predicted when a valley-polarized monolayer TMDC is deposited on a multiferroic substrate. The fundamental principle behind this is an intermediate lattice-ferroelectricity coupling. An electric field changes the surface morphology of the substrate, hence the distance, that is, the exchange interaction, between the substrate and monolayer. The resulting tunable valley splitting brings a new component to electrically controlled valleytronics. [ABSTRACT FROM AUTHOR]