Field Generation Research Articles

Impact of external magnetic field on temperature anisotropy driven Weibel instability in a magnetized plasma

In this paper, we investigate the impact of an external magnetic field on the Weibel instability driven by temperature anisotropy in a magnetized plasma. The study provides the influence of electron temperature anisotropy, considering both cold as well as warm ions. We derive expressions for the growth rate Γ (s−1) in each case to quantify the effect of some specific parameters on the instability. For example, the growth rate is plotted against the magnetic field for three distinct cases: considering only electrons, including cold ions, and incorporating warm ions. It is observed that the growth rate decreases as the applied magnetic field increases. Furthermore, the addition of both cold and warm ions to the plasma significantly influences the observed effects. It can be explained as follows: in the presence of cold ions, the growth rate is decreased with an increase in the wave number kz (cm−1). In addition, a decrease in the growth rate is observed with an increasing wave number in the case of warm ions. Therefore, it can be seen that the Weibel instability, propelled by thermal anisotropy, holds significant implications owing to its prevalence in both astrophysical and laboratory plasmas. The findings presented here are expected to contribute to the advancements in magnetic field generation and particle acceleration in various astrophysical phenomena, including gamma-ray bursts, relativistic collisionless shock fronts, radio supernovae, and pulsar winds.

Toroidal Magnetic Flux Budget in Mean-field Dynamo Model of Solar Cycles 23 and 24

We study the toroidal magnetic flux budget of the axisymmetric part of a data-driven 3D mean-field dynamo model of Solar Cycles 23 and 24. The model simulates the global solar dynamo that includes the effects of the formation and evolution of bipolar magnetic regions (BMRs) emerging on the solar surface. By applying Stokes’s theorem to the dynamo induction equation, we show that the hemispheric magnitude of the net axisymmetric toroidal magnetic field generation rate in the bulk of the convection zone can only partially be estimated from the surface parameters of the differential rotation and the axisymmetric radial magnetic field. The contribution of the radial integral along the equator, which is mostly due to the rotational radial shear at the bottom of the convection zone, has the same magnitude and is nearly in phase with the effect of the surface latitudinal differential rotation. Also, the toroidal field generation rate estimate strongly depends on the latitudinal profile of the surface radial magnetic field near the poles. This profile in our dynamo models significantly deviates from the polar magnetic field distribution observed during the minima of Solar Cycles 22, 23, and 24. The cause of this discrepancy requires further observational and theoretical studies. Comparing the 2D axisymmetric and the 3D nonaxisymmetric dynamo models, we find an increase in the toroidal field generation rate in the 3D model due to the surface effects of BMRs, resulting in an increase in the axisymmetric poloidal magnetic field magnitude.

Rotation plays a role in the generation of magnetic fields in single white dwarfs

ABSTRACT Recent surveys of close white dwarf binaries as well as single white dwarfs have provided evidence for the late appearance of magnetic fields in white dwarfs, and a possible generation mechanism, a crystallization and rotation-driven dynamo has been suggested. A key prediction of this dynamo is that magnetic white dwarfs rotate, at least on average, faster than their non-magnetic counterparts and/or that the magnetic field strength increases with rotation. Here we present rotation periods of ten white dwarfs within 40 pc measured using photometric variations. Eight of the light curves come from TESS observations and are thus not biased towards short periods, in contrast to most period estimates that have been reported previously in the literature. These TESS spin periods are indeed systematically shorter than those of non-magnetic white dwarfs. This means that the crystallization and rotation-driven dynamo could be responsible for a fraction of the magnetic fields in white dwarfs. However, the full sample of magnetic white dwarfs also contains slowly rotating strongly magnetic white dwarfs which indicates that another mechanism that leads to the late appearance of magnetic white dwarfs might be at work, either in addition to or instead of the dynamo. The fast-spinning and massive magnetic white dwarfs that appear in the literature form a small fraction of magnetic white dwarfs, and probably result from a channel related to white dwarf mergers.

The influence of the da Vinci surgical robot on electromagnetic tracking in a clinical environment

Robot-assisted surgery is increasingly used in surgery for cancer. Reduced overview and loss of anatomical orientation are challenges that might be solved with image-guided surgical navigation using electromagnetic tracking (EMT). However, the robot’s presence may distort the electromagnetic field, affecting EMT accuracy. The aim of this study was to evaluate the robot’s influence on EMT accuracy. For this purpose, two different electromagnetic field generators were used inside a clinical surgical environment: a table top field generator (TTFG) and a planar field generator (PFG). The position and orientation of sensors within the electromagnetic field were measured using an accurate in-house developed 3D board. Baseline accuracy was measured without the robot, followed by stepwise introduction of potential distortion sources (robot and robotic instruments). The absolute accuracy was determined within the entire 3D board and in the clinical working volume. For the baseline setup, median errors in the entire tracking volume within the 3D board were 0.9 mm and 0.3° (TTFG), and 1.1 mm and 0.4° (PFG). Adding the robot and instruments did not affect the TTFG’s position accuracy (p = 0.60), while the PFG’s accuracies decreased to 1.5 mm and 0.7° (p < 0.001). For both field generators, when adding robot and instruments, accuracies inside the clinical working volume were higher compared to the entire tracking 3D board volume, 0.7 mm and 0.3° (TTFG), and 1.1 mm and 0.7° (PFG). Introduction of a surgical robot and robotic instruments shows limited distortion of the EMT field, allowing sufficient accuracy for surgical navigation in robotic procedures.

Fluid Mixing during Phase Separation in Crystallizing White Dwarfs

Accurate models of cooling white dwarfs must treat the energy released as their cores crystallize. This phase transition slows the cooling by releasing latent heat and also gravitational energy, which results from phase separation: liquid C is released from the solid C/O core, driving an outward carbon flux. The Gaia color–magnitude diagram provides striking confirmation of this theory by revealing a mass-dependent overdensity of white dwarfs, indicating slowed cooling at the expected location. However, the observed overdensity is enhanced relative to the models. Additionally, it is associated with increased magnetism, suggesting a link between crystallization and magnetic field generation. Recent works aimed at explaining an enhanced cooling delay and magnetic field generation employ a uniform mixing prescription that assumes large-scale turbulent motions; we show here that these calculations are not self-consistent. We also show that thermohaline mixing is most likely efficient enough to provide the required chemical redistribution during C/O phase separation, and that the resulting velocities and mixing lengths are much smaller than previous estimates. These reduced fluid motions cannot generate measurable magnetic fields, suggesting any link with crystallization needs to invoke a separate mechanism. Finally, this mixing alters the chemical profiles, which in turn affects the frequencies of the pulsation modes.

Anti-Gravity System Based on Magnetic Levitation Technology

This paper presents a design of an anti-gravity system based on magnetic levitation technology. The system utilizes the force generated by magnetic principles to counteract gravity and achieve object suspension and control. The design objective is to achieve portable maglev technology for everyday use. Specific requirements include adjustable speed range, endurance time, effective suspension range, mass, control mode, safety, magnetic field strength, suspension stability, altitude control precision, resistance to strong magnetic field interference, and portability. The system structure includes suspension device, magnetic field generator, sensor, and control system. Control strategies such as PID control, fuzzy control, and sliding mode control can be employed, and signal communication can be achieved through Bluetooth, Wi-Fi, or fiber optic communication. By selecting and designing appropriate control strategies and integrating suspension, magnetic field generator, and sensor components, the anti-gravity system based on magnetic levitation technology can achieve height control and suspension stability.

Terahertz radiation generation from amplitude-modulated laser filament interaction with a magnetized plasma

The availability of high-power lasers open new frontiers of Terahertz (THz) optics. In this paper, we present a mechanism for the enhanced THz field generation from the laser wakefield excitation during the interaction of an amplitude-modulated laser filament with a magnetized plasma. The derivation of electric and magnetic wakefields in axially magnetized plasma is obtained using the perturbative approach. Amplitude-modulated laser filament generates a significantly stronger transverse current due to laser intensity redistribution by the amplitude modulation. The modulation index of the amplitude modulated laser pulse is used to control the transverse current at THz frequency. Fourfold enhancement takes place in THz field strength for higher values of the modulation index (0–0.4). Also, the conversion efficiency of this mechanism is estimated as [Formula: see text] that can be enhanced for higher modulation index. Scaling laws are provided for controlling and optimization of generated THz field. This work may be crucial in exploring THz optical phenomena such as THz field-induced Kerr effects and many other nonlinear effects.

PANOVA-4 (EF-39): Pilot study of tumor treating fields (TTFields) therapy with atezolizumab, gemcitabine (GEM), and nab-paclitaxel (NabP) as first-line (1L) treatment for metastatic pancreatic ductal adenocarcinoma (mPDAC).

TPS718 Background: TTFields are electric fields that exert physical forces to disrupt cellular processes critical for cancer cell viability and tumor progression. TTFields therapy is noninvasive, locoregional, and is delivered via a portable electric field generator and skin-placed arrays. TTFields therapy has low risk of systemic toxicity and is approved for glioblastoma (and grade 4 glioma in Europe), and pleural mesothelioma. In vitro, TTFields (150 kHz) application decreased pancreatic cancer cell proliferation and clonogenicity; in vivo, TTFields concomitant with chemotherapy (chemo) had greater antitumor effect than chemo alone in orthotopic pancreatic tumors. Co-application of TTFields with immune checkpoint inhibitors (ICIs) significantly decreased tumor volume, increased tumor infiltration and IFN-γ production, and did not impede ICI-induced effector memory T-cell production versus in vivo controls. The pilot (phase 2) PANOVA clinical study (NCT01971281) showed safety and feasibility with TTFields therapy plus NabP and GEM in metastatic and locally advanced pancreatic adenocarcinoma (LAPC). The randomized, pivotal (phase 3) PANOVA-3 clinical study (NCT03377491), evaluating TTFields therapy with GEM and NabP in LAPC, is ongoing. Methods: PANOVA-4 (pilot, single-arm clinical study) assesses the safety and efficacy of TTFields therapy (NovoTTF-200T device) concomitant with atezolizumab, GEM, and NabP as 1L treatment for mPDAC. Eligible patients (pts) are ≥18 years of age and have a new mPDAC diagnosis, measurable abdominal disease per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1, Eastern Cooperative Oncology Group performance status (ECOG PS) 0–1, and no prior systemic PDAC therapy. Atezolizumab (1680 mg, IV infusion) is given before chemo on day 1 of each 28-d cycle, with NabP (125 mg/m2 IV) and GEM (1000 mg/m2 IV) given on days 1, 8, and 15. TTFields therapy (150 kHz) is delivered for ≥18 h/d until disease progression per RECIST v1.1 or loss of clinical benefit. Clinical follow-up occurs every 4 weeks (q4w) with CT scans q8w. Survival is assessed every 3 mo post last on-site visit. The primary endpoint is disease control rate (DCR). Secondary endpoints include overall survival (OS), progression-free survival (PFS), 1-year OS rate, objective response rate, PFS at 6 mo, duration of response, and safety. 76 pts are required to achieve 80% power (1-sided α level 0.05) to detect a 63% DCR vs historical 48% DCR in pts with mPDAC receiving 1L GEM and NabP. Clinical trial information: EUCTR2022-003157-55 .

Design consideration on integration of mechanical intravascular ultrasound and electromagnetic tracking sensor for intravascular reconstruction

PurposeConsidering vessel deformation, endovascular navigation requires intraoperative geometric information. Mechanical intravascular ultrasound (IVUS) with an electromagnetic (EM) sensor can be used to reconstruct blood vessels with thin diameter. However, the integration design should be evaluated based on the factors affecting the reconstruction error.MethodsThe interference between the mechanical IVUS and EM sensor was measured in different relative positions. Two designs of the integrated catheter were evaluated by measuring the reconstruction errors using a rigid vascular phantom.ResultsWhen the distance from the EM sensor to the field generator was 75 mm, the interference from mechanical IVUS to an EM sensor was negligible, with position and rotation errors less than 0.1 mm and 0.6°, respectively. The reconstructed vessel model for proximal IVUS transducer had a smooth surface but an inaccurate shape at large curvature of the vascular phantom. When the distance to the field generator was 175 mm, the error increased significantly.ConclusionPlacing the IVUS transducer on the proximal side of the EM sensor is superior in terms of interference reduction but inferior in terms of mechanical stability compared to a distal transducer. The distal side is preferred due to better mechanical stability during catheter manipulation at larger curvature. With this configuration, surface reconstruction errors less than 1.7 mm (with RMS 0.57 mm) were achieved when the distance to the field generator was less than 175 mm.

In situ irradiated XPS investigation on S-scheme TiO2/Bi2S3 photocatalyst with high interfacial charge separation for highly efficient photothermal catalytic CO2 reduction

The combination of S-scheme heterojunction and photothermal effect is a promising strategy to achieve efficient CO2 photoreduction into solar fuel due to the boosted charge carrier separation efficiency and faster surface reaction rate. Herein, unique photothermal-coupled TiO2/Bi2S3 S-scheme heterojunction nanofibers were fabricated and applied to a full-spectrum CO2 photoreduction system. Density functional theory calculation and experimental analyses have confirmed the generation of the internal electric field and the S-scheme electron transfer pathway, leading to a highly efficient charge carrier separation. Thanks to the excellent photothermal conversion capacity of Bi2S3, the photogenerated electron transfer rate, and surface reaction rate were further accelerated in hybrid photocatalysts. Under the synergistic effect of S-scheme heterojunction and photothermal effects, the optimal TiO2/Bi2S3 nanofibers achieved 7.65 μmol h–1 of CH4 production rate, which is 5.24 times higher than that of pristine TiO2. Moreover, the morphology reconstruction of Bi2S3 in hybrids facilitates the CH4 selectivity was significantly improved from 64.2% to 88.7%. Meanwhile, the CO2 photoreduction reaction route over TiO2/Bi2S3 nanofibers was investigated based on in-situ Fourier transform infrared spectra. This work provides some useful hints for designing highly efficient photothermal-coupled photocatalysts for CO2 photoreduction.

Large-eddy simulation of the effects of horizontal and vertical adjustments in a wind farm

In order to study the fine structural characteristics of the wind field and wind power generation in wind farms, large-eddy simulations (LES) with different layouts are carried out under a given wind direction. In the simulation, a single wind turbine can produce a wake effect, reducing the wind within 2 km by 50%, and the influence between wind turbines gradually decreases as the distance between the wind turbines increases. To minimize the impact of the wake effect between the turbines, the simulation considering horizontal and vertical staggering of the wind farm is conducted. Under the prevailing wind, the optimal power output for the entire wind farm is obtained when a horizontal staggering degree θ of 16.7 is used and no vertical staggering is adapted. Unexpectedly, vertical interleaving hardly increases power generation in terms of the whole wind farm. This research result has certain implications for the optimal layout of wind farms in practical applications, especially in sites with a well-defined prevailing wind direction.

Role of galactic disc thickness in magnetic field generation

A large variety of galaxies have magnetic structures of lengthscales comparable with their radius. Theoretically, their existence is based on the dynamo mechanism. It is based on alpha-effect characterizing helicity of the turbulent motions and differential rotation which is connected with changing angular velocity. The field can be destroyed by turbulent diffusion, so the mechanism is threshold and can be realized only for the case when first and second effect are more intensive than the third one. Equations of magnetohydrodynamics that are used to describe the dynamo mechanism, are too difficult to be solved. So, usually different approximation taking into account details of astrophysical objects are used. As for galaxies, a thin disc approximation has been developed. It works properly for galactic objects with small half-thickness. However, as for thick discs we should take a model which uses more complicated structure of the field. Here we find the threshold for the field generation for thick astrophysical discs.

Constructing novel deep eutectic composites based on hydrogen bond network as anode material for lithium-ion batteries

The replacement of metallic materials with non-metallic materials as anode electrodes for lithium-ion batteries (LIBs) is an increasing hot spot for constructing a new generation of energy storage field. Here, a novel deep eutectic composites material consisting of quaternary ammonium salts (QASs) and N-methyl pyrrolidone (NMP) on the basis of hydrogen bonding reaction is used as the anode material of LIBs, boasting numerous advantages, including facile synthesis, environmental friendliness, superb conductivity, self-healing property, and multiple active sites to provide capacity. Typically, tetraethylammonium chloride (TEACl)/NMP delivered a reversible specific capacity of 764.8 mAh/g at 100 mA/g after cycling 420 times and coulombic efficiency is maintained near 100 % after 1000 cycles at 100 mA/g. The availability of hydrogen bonding network reduces the lattice energy of its components and creates defects, which is more favorable for the intercalation reaction in LIBs. Concurrently, the effect of hydrogen bonding reaction and the natural mobility of the deep eutectic composites exhibit high self-healing properties, facilitating the repair of the reaction interface in real time. An abundance of active sites that can bind Li+ to form LiH is used to provide capacity, which is also confirmed by density functional theory (DFT) method.

Numerical simulation of electricity generation potential through five vertical wells at Fengshun geothermal field in China

Fengshun geothermal field is the first medium low temperature geothermal field to exploit geothermal energy for electricity generation in China. Due to poor economy and low efficiency, the geothermal power plant was forced to shut down in 2016. In this work, based on the geological data of the well ZK11, we proposed a new heat exploitation scheme with five vertical wells and a binary system, computed the power generation potential and efficiency, and analyzed the main factors influencing heat production. The results indicate that through the five vertical wells, the system attains an electrical power of 1.49–1.05 MW, a reservoir impedance of 0.23–0.29 MPa/(kg/s), a pump power of 0.30–0.49 MW, and an electrical energy efficiency of 4.55–2.12. The electric power of unit flow rate is 22.4–31.7 times that of the existing power plant. Thus, this five-vertical-well system has significant development potential for medium low temperature hydrothermal field. The sensitivity analysis indicates that overburden and underburden permeability, water production rate and injection temperature have a significant impact on heat production performance. Increasing the overburden or underburden permeability will significantly reduce reservoir impedance and increase energy efficiency. Reducing the water production rate and injection temperature within a certain range can improve energy efficiency. This work also provides a guideline for the exploitation and power generation of future medium low temperature hydrothermal field in Fengshun and other sites under similar conditions.

Parallel and automatic mesh sizing field generation for complicated CAD models

PurposeThe purpose of this paper is to present an automatic approach for mesh sizing field generation of complicated computer-aided design (CAD) models.Design/methodology/approachIn this paper, the authors present an automatic approach for mesh sizing field generation. First, a source point extraction algorithm is applied to capture curvature and proximity features of CAD models. Second, according to the distribution of feature source points, an octree background mesh is constructed for storing element size value. Third, mesh size value on each node of background mesh is calculated by interpolating the local feature size of the nearby source points, and then, an initial mesh sizing field is obtained. Finally, a theoretically guaranteed smoothing algorithm is developed to restrict the gradient of the mesh sizing field.FindingsTo achieve high performance, the proposed approach has been implemented in multithreaded parallel using OpenMP. Numerical results demonstrate that the proposed approach is remarkably efficient to construct reasonable mesh sizing field for complicated CAD models and applicable for generating geometrically adaptive triangle/tetrahedral meshes. Moreover, since the mesh sizing field is defined on an octree background mesh, high-efficiency query of local size value could be achieved in the following mesh generation procedure.Originality/valueHow to determine a reasonable mesh size for complicated CAD models is often a bottleneck of mesh generation. For the complicated models with thousands or even ten thousands of geometric entities, it is time-consuming to construct an appropriate mesh sizing field for generating high-quality mesh. A parallel algorithm of mesh sizing field generation with low computational complexity is presented in this paper, and its usability and efficiency have been verified.

Magnetic hybrid Pd/Fe-oxide nanoparticles meet the demands for ablative thermo-brachytherapy

Objective To investigate the potential of hybrid Pd/Fe-oxide magnetic nanoparticles designed for thermo-brachytherapy of breast cancer, considering their specific loss power (SLP) and clinical constraints in the applied magnetic field. Methods Hybrid nanoparticles consisting of palladium-core and iron oxide shell of increasing thickness, were suspended in water and their SLPs were measured at varying magnetic fields (12–26 mT peak) and frequencies (50–730 kHz) with a commercial alternating magnetic field generator (magneTherm™ Digital, nanoTherics Ltd.). Results Validation of the heating device used in this study with commercial HyperMag-C nanoparticles showed a small deviation (±4%) over a period of 1 year, confirming the reliability of the method. The integration of dual thermometers, one in the center and one at the bottom of the sample vial, allowed monitoring of homogeneity of the sample suspensions. SLPs measurements on a series of nanoparticles of increasing sizes showed the highest heating for the diameter of 21 nm (SLP = 225 W/g) at the applied frequencies of 346 and 730 kHz. No heating was observed for the nanoparticles with the size <14 nm, confirming the importance of the size-parameter. The heating ability of the best performing Pd/Fe-oxide-21 was calculated to be sufficient to ablate tumors with a radius ±4 and 12 mm using 10 and 1 mg/mL nanoparticle concentration, respectively. Conclusions Nanoparticles consisting of non-magnetic palladium-core and magnetic iron oxide shell are suitable for magnetic hyperthermia/thermal ablation under clinically safe conditions of 346 kHz and 19.1 mT, with minimal eddy current effects in combination with maximum SLP.

Stochastic finite element modeling of heterogeneities in massive concrete and reinforced concrete structures

AbstractThe lifespan of a reinforced concrete (RC) structure can be greatly influenced by the spatial variability of its material characteristics which, in particular, explains the observed or measured reduction of the tensile strength at first crack when the volume under tension increases. This paper discusses the ability of accounting for the spatial variability of the tensile strength of concrete in RC structures using a stochastic finite element (SFE) method based on random field simulations. In this work, the generation of random fields on the concrete tensile strength aims at computing the force corresponding to the first crack occurrence, and the reduced tensile strength of the structure. The method can be applied in particular to large‐sized structures, which show a pronounced size effect, for different types of loading. The method consists of, first, estimating the mean of the random field, using the analytical approach of the weakest link and localization method (WL ). Then, the discretized random field is defined on a particular 2D or 3D grid, and it is finally projected on the finite element mesh of the studied structure. The study of the parameters that influence the prediction of the cumulative density functions (CDFs) of the rupture force or the tensile strength is highlighted using experimental series of concrete beams having different volumes and subjected to 4‐point bending loading. Moreover, the SFE method is applied to a RC tie‐beam under tensile loading, characterized by a weak stress gradient, which complicates the prediction of crack positions.

Modeling advanced air mobility aircraft in data-driven reduced order realistic urban winds

The concept of Advanced Air Mobility involves utilizing cutting-edge transportation platforms to transport passengers and cargo efficiently over short distances in urban and suburban areas. However, using simplified atmospheric models for aircraft simulations can prove insufficient for modeling large disturbances impacting low-altitude flight regimes. Due to the complexities of operating in urban environments, realistic wind modeling is necessary to ensure trajectory planning and control design can maintain high levels of safety. In this study, we simulate the dynamic response of a representative advanced air mobility platform operating in wing-borne flight through an urban wind field generated using Large Eddy Simulations (LES) and a wind field created using reduced-order models based on full-order computational solutions. Our findings show that the longitudinal response of the aircraft was not greatly affected by the fidelity of the LES models or if the spatial variation was considered while evaluating the full-order wind model. This is encouraging as it indicates that the full LES generation of the wind field may not be necessary, which decreases the complexity and time needed in this analysis. Differences are present when comparing the lateral response, owing to the differences in the asymmetric loading of the planform in the full and reduced order models. These differences seen in the lateral responses are expected to increase for planforms with smaller wing loadings, which could pose challenges. Additionally, the response of the aircraft to the mean wind field, the temporal average of the full order model, was misrepresentative in the longitudinal response and greatly under-predicted control surface activity, particularly in the lateral response.

Active generation and control of radial electric field by local neutral beamlets injection in tokamaks

The radial electric field plays an important role in plasma confinement in tokamaks and can be generated through neutral beam injection. In this study, we propose a model for calculating the radial electric field resulting from tangential local neutral beamlet injection, aiming to externally control and improve plasma confinement. The Neutral beamlet ion and Energetic particles Orbit mover and Electric field solver code has been developed to analyze this issue, and its simulation results have been validated against results from other codes as well as measurements from correlation reflectometers. The charge separation is primarily caused by the redistribution and loss of beam ions due to magnetic gradient and curvature drift as well as collision effects, and it is maintained through continuous beamlet injection. The electric field is calculated using Poisson’s equation, taking into account both classical and neoclassical polarization effects. The results demonstrate that despite the high losses and low heating efficiency associated with localized beamlets, they are capable of generating a significant radial electric field characterized by a steep gradient. This presents opportunities for external control of the electric field, potentially enhancing plasma confinement.

Nanowire-assisted electrochemical perforation of graphene oxide nanosheets for molecular separation

Two-dimensional nanosheets, e.g., graphene oxide (GO), have been widely used to fabricate efficient membranes for molecular separation. However, because of poor transport across nanosheets and high width-to-thickness ratio, the permeation pathway length and tortuosity of these membranes are extremely large, which limit their separation performance. Here we report a facile, scalable, and controllable nanowire electrochemical concept for perforating and modifying nanosheets to shorten permeation pathway and adjust transport property. It is found that confinement effects with locally enhanced charge density, electric field, and hydroxyl radical generation over nanowire tips on anode can be executed under low voltage, thereby inducing confined direct electron loss and indirect oxidation to reform configuration and composition of GO nanosheets. We demonstrate that the porous GO nanosheets with a lot of holes are suitable for assembling separation membranes with tuned accessibility, tortuosity, interlayer space, electronegativity, and hydrophilicity. For molecular separation, the prepared membranes exhibit quadruple water permeance and higher rejections for salts (>91%) and small molecules (>96%) as/than original ones. This nanowire electrochemical perforation concept offers a feasible strategy to reconstruct two-dimensional materials and tune their transport property for separation.