Assistance Of Electric Field Research Articles

Arsenic(V) removal from water using polyelectrolyte enhanced ultrafiltration with poly(dimethyldiallylammonium chloride) (PDADMAC): Ion-selectivity based modeling and electric field influence

Polyelectrolyte enhanced ultrafiltration (PEUF) shows promise for arsenic removal. However, competing ions may serve as potential limiting factors, and membrane fouling caused by aggregation of polyelectrolytes may impact PEUF performance. This study employed poly(dimethyldiallylammonium chloride) (PDADMAC) for arsenate (As(V)) removal via ultrafiltration, and the effect of electric field assistance on PEUF performance was investigated. Ion exchange experiments between Cl- and typical anions were conducted in a binary system to determine the selectivity coefficients (Ksel) of PDADMAC for different anions. The affinity of PDADMAC towards common monovalent anions was found to be Br->NO3->Cl->H2PO4->HCO3->H2AsO4-, while its affinity for divalent anions decreased in the order SO42-> HPO42-> HAsO42-. By determining the selectivity coefficients of various anions with PDADMAC and utilizing mass conservation models, a phase distribution model for anions during PEUF process was developed to predict As(V) removal. Predictions were made regarding the enhanced ultrafiltration efficiency for As(V) under different conditions (pH, ionic strength, and competing anions) in complex water environments. As the dosage of PDADMAC increased, the removal of As(V) from the actual water sample spiked with an initial concentration of 0.2 mM exceeded 90 %, and the experimental results closely matched the model predictions. The impact of electric field on the PEUF process was investigated by placing electrodes on both sides of the ultrafiltration membrane. Results showed that the ultrafiltration membrane, when positively charged by an electric field, repelled cationic PDADMAC, thereby alleviating membrane fouling. However, the cleaner membrane led to increased leakage of PDADMAC molecules, resulting in the co-loss of As with PDADMAC and consequently reducing the overall As removal.

Morphological and structural properties of antimony selenide thin films deposited with external electric field assistance

A method for producing a thin semiconductor film of antimony selenide (Sb2Se3) via vacuum thermal evaporation with the assistance of an electric field was presented. The morphological, elemental and structural properties of the thin films were characterized using X-ray diffraction and scanning electron microscopy (with energy dispersive X-ray spectroscopy). It was found that an applied constant electric field plays an important role in obtaining Sb2Se3 thin films with the desired morphological and structural properties. The latter is a useful tool for controlling charge transport properties in thin films.

A comprehensive review on the fundamental principles, innovative designs, and multidisciplinary applications of micromixers

This paper comprehensively reviews the fundamental principles, innovative designs, and multidisciplinary applications of micromixers. First, it introduces the fundamental principles of fluid mixing in micromixers, including passive and active mixing mechanisms, and the flow characteristics of fluids at the microscale. Subsequently, it focuses on the innovative design of passive micromixers, covering a variety of designs, such as obstacle structures, curved serpentine structures, groove structures, separation and recombination structures, topology optimization structures, and baffle structures, and analyzes the effects of different structures on mixing efficiency and pressure drop. In addition, it also studies the innovative design of active micromixers, including magnetic field assistance, electric field assistance, surface acoustic wave assistance, and thermal effect assistance, and analyzes the effects of different driving modes on mixing efficiency. Finally, it outlines the multidisciplinary applications of micromixers in the fields of biomedicine, chemical analysis, environmental monitoring and control, and new energy. This review aims to provide a comprehensive reference for the research and application of micromixers and promote their application in more fields.

Layered double hydroxide assembled on a metal–organic framework coupled with polyaniline as pseudocapacitive anode for phosphorus capture

Excessive phosphorus is detrimental to supporting the proper function of aquatic ecosystems. Capacitive deionization (CDI) is an emerging, highly efficient, eco-friendly electrochemical technology that eliminates phosphorus from wastewater. In this work, a novel LDH@MOF/PANI composite was successfully fabricated by utilizing polyaniline (PANI) as a conductive substrate and metal–organic framework (MOF) as a self-sacrificial template for layered double hydroxide (LDH). The results demonstrated that LDH and PANI are favorable for improving the pore structure features, enriching the phosphorus binding sites, and strengthening the electrochemical performance of the electrode materials. Accordingly, the LDH@MOF/PANI electrode presented a superior phosphorus capture capacity than LDH@MOF and MOF. The isotherm and kinetic experiments revealed that the phosphorus capture by LDH@MOF/PANI is a chemisorption-dominated process associated with heterogeneous adsorption. The potential interference with phosphorus uptake was also assessed by focusing on several vital factors. Eventually, the possible mechanism suggested that ligand exchange, anion exchange, hydrogen bond, electrostatic attraction, and electric field assistance participate in the phosphorus uptake process. This work presents promising insight into the assembly design and rational construction of LDH-based pseudocapacitive anode for phosphorus capture.

Effect of Plasma Electric Field Assistance on the Freezing Process and Ice Crystal Formation of Bactrian Camel Meat

Background: The longissimus dorsi muscle of the camel was chosen as the experimental material in order to investigate the impact of plasma electric field assisted freezing on the quality and freezing process of Bactrian camel meat. Methods: The effect of the auxiliary plasma electric field of different field strengths (1 kV/m, 3 kV/m and 5 kV/m) on the freezing velocity of the camel meat and the distribution of ice crystals as well as the diameter and roundness of ice crystal in the frozen meat were studied and analyzing them with the help of the thermodynamic theory. Result: The findings demonstrated that the meat samples in the auxiliary 5 kV/m plasma field environment took 60 min and 30 min, respectively, at -20°C and -35°C, to pass the maximal ice crystal production zone. The tissue sections revealed that at -20°C and -35°C assisted 5 kV/m plasma field freezing, the smallest ice crystal area and grain size were formed, the roundness of the ice crystals was highest. Using Boltzmann’s entropic equation to calculate the system’s entropy, the results revealed that the meat samples frozen by the aided 5 kV/m plasma electric field had the lowest entropy at -20°C and -35°C. The electric field assisted freezing requires less energy to improve the subcooling degree and accelerate the freezing rate of meat samples, proving that the auxiliary 5 kV/m plasma electric field can significantly improve the system frozen meat moisture vitrification degree and can make the crystallization process more controllable.

Low voltage electric field mediating gravity-driven membrane bioreactor in treating saline wastewater: removal improvement and membrane fouling control

Gravity-driven membrane bioreactor (GDMBR) endowed with low maintenance and energy consumption owing to its combinations between biological degradation and membrane rejection, however, has not been reported in treating the saline wastewater due to the potential biological inhibition. This study investigated the effects of salt on GDMBR performance, and introduced a novel low voltage electric field (eGDMBR) with hopes to mediate the biological activity and improve the filtration performance. The influence of different low voltage electric fields (0.25 V, 0.50 V, and 0.75 V) on the flux variations and contaminants removal of eGDMBR were investigated. The results demonstrated that integrating low voltage electric field into GDMBR would not impact the appearance of flux stabilization, but delivered a significant influence on its stabilized flux level, and 0.50 V was the optimized voltage, contributing to a substantial flux improvement of 47.10 % in eGDMBR-0.50. Moreover, with the assistance of low voltage electric fields, eGDMBR process obtained an effective removal of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total phosphorus (TP), accounting for average removal efficiency of 54.01 %, 73.08 % and 25.74 %, respectively. Compared to the control, coupling 0.50 V voltage electric field to GDMBR was beneficial to engineer a loose, porous and heterogeneous structure of membrane biofilm and also reduce the accumulation of extracellular polymeric substance (EPS), significantly contributing to alleviating the membrane fouling. Furthermore, with the assistance of low voltage electric fields, the Proteobacteria was enriched by a relative abundance of 58.58 % in the membrane biofilm of eGDMBR-0.50, which was in favor of the degradation of COD and NH4+-N. Therefore, these findings indicated that eGDMBR conferred significant superiorities in treating the saline wastewater and mitigating membrane fouling.

Enhancement of Mass Transfer Process for Photocatalytic Reduction in Cr(VI) by Electric Field Assistance.

The removal of Cr(VI), a highly-toxic heavy metal, from industrial wastewater is a critical issue in water treatment research. Photocatalysis, a promising technology to solve the Cr(VI) pollution problem, requires urgent and continuous improvement to enhance its performance. To address this need, an electric field-assisted photocatalytic system (PCS) was proposed to meet the growing demand for industrial wastewater treatment. Firstly, we selected PAF-54, a nitrogen-rich porous organic polymer, as the PCS's catalytic material. PAF-54 exhibits a large adsorption capacity (189 mg/g) for Cr(VI) oxyanions through hydrogen bonding and electrostatic interaction. It was then coated on carbon paper (CP) and used as the photocatalytic electrode. The synergy between capacitive deionization (CDI) and photocatalysis significantly promotes the photoreduction of Cr(VI). The photocatalytic performance was enhanced due to the electric field's influence on the mass transfer process, which could strengthen the enrichment of Cr(VI) oxyanions and the repulsion of Cr(III) cations on the surface of PAF-54/CP electrode. In addition, the PCS system demonstrates excellent recyclability and stability, making it a promising candidate for chromium wastewater treatment.

Nanozyme-based Clusterphene for Enhanced Electrically Catalytic Cancer Therapy.

Nanozyme mediated catalytic therapy is an attractive strategy for cancer therapy. However, the nanozymes are tended to assemble into 3D architectures, resulting in poor catalytic efficiency for therapy. This study designs the assembly of nanozymes and natural enzymes into the layered structures featuring hexagonal pores as nanozyme clusterphene and investigates their catalytic therapy with the assistance of electric field. The nanozyme-based clusterphene consists of polyoxometalate (POM) and natural glucose oxidase (GOx), named POMG-based clusterphene, which facilitate multi-enzyme activities including peroxidase (POD), catalase (CAT), and glutathione oxidase (GPx). The highly ordered layers with hexagonal pores of POMG units significantly improve the peroxidase-like (POD-like) activity of the nanozyme and thus the sustained production of reactive oxygen species (ROS). At the same time, GOx can increase endogenous H2O2 and produce gluconic acid while consuming glucose, the nutrient of tumor cell growth. The results indicate that the POD-like activity of POMG-based clusterphene increase approximately sevenfold under electrical stimulation compared with Nd-substituted keggin type POM cluster (NdPW11). The experiments both in vitro and in vivo show that the proposed POMG-based clusterphene mediated cascade catalytic therapy is capable of efficient tumor inhibiting and preventing tumor proliferation in tumor-bearing mice model, promising as an excellent candidate for catalytic therapy.

Ultraefficient Li+/Mg2+ separation with MXene/CNT membranes under electric field assistance

Similar physicochemical properties render the separation of Li+/Mg2+ from salt lake brine difficult for two-dimensional (2D) membranes. Herein, ultraefficient Li+/Mg2+ separation was achieved under the influence of an electric field using MXene/carbon nanotube (CNT) membranes developed on tubular ceramic substrates via thermal crosslinking. Crosslinking reactions between CNTs and MXene yielded well–intercalated CNTs between MXene nanosheets, forming antiswelling MXene/CNT membranes (MCMs) (interlayer spacing: 8.04 Å) suitable for Li+/Mg2+ separation. At 2.8 V applied voltage, the MCMs exhibited Li+ flux of 0.0491 mol m−2 h−1 and high Li+/Mg2+ selectivity of 54.5, which outperform existing state–of–the–art 2D membranes. Specifically, under a positive electric field, Li+ with a small hydration diameter and low hydration energy permeated through the membrane nanochannels more easily than Mg2+, increasing and decreasing Li+ and Mg2+ flux, respectively. Additionally, Mg2+ retention was enhanced via the complexation of enriched Mg2+ with –OH and –COOH on the membrane surface. The MXene membrane surface was thus reconfigured to be positively charged, inducing effective Mg2+ rejection. This study offers a novel and practical approach for efficiently separating Li+/Mg2+ as well as monovalent/multivalent ions.

Achieving SiC joints with outstanding high-temperature property via flash brazing using FeCoCrNiCu high-entropy alloy

In this paper, the “flash brazing” of SiC is successfully achieved using FeCoCrNiCu alloy in air for seconds at an ultra-low furnace temperature of 400 ℃. The interface temperature reaches over 1000 ℃ in 1 s at an ultra-fast rate via the electric field assistance. The reaction layer of the joint consists mainly of Cr23C6 and the silicides of Fe, Co, Ni, and Cu. With the increase of brazing holding time, Cu gradually precipitates from the alloy, and the shear strength of the joints first increases and then decreases. The maximum strength value is 80 MPa at the test temperature of 800 ℃. This approach could help significantly improve the efficiency of ceramic bonding and achieve low-temperature joining for high-temperature applications.

Microbial electrochemical composting: A sustainable strategy to enhance lignocellulose conversion into humus

Achieving satisfactory levels of humification during composting is recognised as a challenge due to the recalcitrance of lignocellulose and the uncertainty of current biofortification techniques. Therefore, a novel microbial electrochemical composting technology was developed from insights into microbiology and electrochemistry in this study to strengthen microorganisms’ function promoting the conversion from lignocellulose into humus. Firstly, a fungus (Aspergillus oryzae) was introduced which exhibited a higher propagation rate (29.9%) and secreted more lignocellulose-degrading enzymes (18.9–74.9%) under electric field assistance. Subsequently, an in-situ composting trial was conducted with supplementary electric fields simultaneously combined with Aspergillus oryzae inoculation. The abundance of Aspergillus oryzae increased 3.0–7.8-fold under the influence of electric field, which enabled the production of more extracellular enzymes (by 8.4–149.5%) to promote the conversion of lignocellulose to humus (increased by 7.0–20.2%). The results indicated electric field can act as an activator of Aspergillus oryzae and magnify its function. It provides an innovative and efficient technique for enhancing humification during composting that contributes to the conversion of organic waste into high-quality soil conditioner products.

Efficient utilization of photoelectron-hole at semiconductor-microbe interface for pyridine degradation with assistance of external electric field

In this study, enhanced pyridine bio-photodegradation with assistance of electricity was achieved. Meanwhile, photoelectron-hole played a vital role in accelerating pyridine biomineralization. The significant separation of photoelectron-hole was achieved with an external electric field, which provided sufficient electron donors and acceptors for pyridine biodegradation. The enhanced electron transport system activity also revealed the full utilization of photoelectron-hole by microbes at semiconductor-microbe interface with assistance of electricity. Microbial community analysis confirmed the enrichment of functional species related to pyridine biodegradation and electron transfer. Microbial function analysis and microbial co-occurrence networks analysis indicated that upregulated functional genes and positive interactions of different species were the important reasons for enhanced pyridine bio-photodegradation with external electric field. A possible mechanism of enhanced pyridine biodegradation was proposed, i.e., more photoelectrons and holes of semiconductors were utilized by microbes to accelerate reduction and oxidation of pyridine with the assistance of electrical stimulation. The excellent performance of the photoelectrical biodegradation system showed a potential alternative for recalcitrant organic wastewater treatment.

Ferroelectric spontaneous polarization assisted TiO2@BaTiO3@Ag photoanode for efficient photoelectrochemical water splitting via BaTiO3 phase regulation

In this work, TiO2@BaTiO3@Ag composite photoanodes were synthesized. By fabricating BaTiO3 with different phase structures, the influence of crystalline phase of BaTiO3 on PEC water splitting was investigated. Furthermore, hot electrons generated in the plasmonic effect of Ag nanoparticles can be efficiently injected into TiO2 film with the assistance of spontaneous polarization electric field (SPEF). Benefitting from this SPEF coupled plasmonic effect, the optimized TiO2@BaTiO3@Ag photoanode (T-TB@Ag) achieved a maximum photocurrent density of 7.30 mA cm−2 (1.23 V vs. RHE) under AM 1.5 G simulated sunlight, which is 6 times that of the non-ferroelectric cubic phase TiO2@BaTiO3@Ag photoanode (C-TB@Ag). This ferroelectric spontaneous polarization coupling plasmonic effect can effectively reduce carrier recombination and promote the separation of photocarriers, which ultimately increases PEC water splitting activity.

Fabrication and evaluation of a molecular-imprinted-polymer functionalized electrode for selective electric field-assisted solid-phase microextraction of phytohormones

Specific extraction and separation plays a pivotal role in the accurate quantification of trace phytohormones (PHs). However, due to their high polarity, specific capture of PHs is challenging. In this study, under the assistance of electric field, a molecular-imprinted-polymer functionalized electrode (MIP@ED) was in-situ prepared using 3-indoleacetic acid (IAA) as template and employed as the adsorbent of electric field-assisted solid-phase microextraction (EA-SPME) for specific capture of PHs. Results showed that the implementation of electric field during the preparation of MIP@ED and EA-SPME procedures improved the extraction selectivity, the selective factors towards IAA and its structural analogues increased from 2.09 to 2.45 to 2.88–3.51. Under the optimum conditions, the proposed MIP@ED/EA-SPME was combined with HPLC technique to monitor trace PHs in water and agricultural products. The achieved limits of detection were in the ranges of 0.0053–0.011 μg/L and 0.048–0.12 μg/kg for water and agricultural product, respectively. The established approach was successfully applied to quantify trace PHs in real samples, and the spiked recoveries varied from 84.0 % to 118 % with good repeatability (RSDs blow 10 %). The obtained results provided clear evidence that the developed approach employing the MIP@ED/EA-SPME technique demonstrated high sensitivity, good selectivity, satisfactory reproducibility and environmental friendliness in the quantification of trace PHs in complex samples. In addition, the current study supplied a new strategy to enhance the specific recognition performance of MIP-based SPME.

Degradation of phenylarsonic acid in phenylarsenic chemical warfare agents by Fe-modified CNT electroactive filter activating peroxymonosulfate: Performance and mechanism

Phenylarsonic acid (PAA) is a major organic arsenic contaminant in abandoned arsenic-based chemical weapons areas, and poses threats to the water environment due to potential arsenic pollution; However, relevant remediation methods are lacking. In this study, a Fe-modified carbon nanotube (CNT) electroactive filter was developed for peroxymonosulfate (PMS) activation towards PAA decontamination. The developed system can realise synchronous adsorption and oxidation of PAA (85.6 %) with PMS (1.5 mM) under electric field assistance (-1 V). Radicals (SO4•– and HO•) and non-radicals (1O2) contributed to PAA degradation and the formation of As (V). The preferable PAA degradation efficiency stemmed from facilitated Fe (II)/Fe (III) redox cycles with applied electric field assistance. Secondary inorganic arsenic could also be immobilised as FeOAs bonds on the Fe-modified CNT filter. Additionally, PAA degradation pathways were proposed based on density functional theory (DFT) and intermediate identification. The system efficacy was also evaluated by regulating the critical operational parameters (applied voltage, flow rate, PMS concentration, pH and co-existing anions) and using complicated matrices (tap water and lake water). Our findings provide a new solution for PAA remediation and simultaneous immobilisation of secondary inorganic arsenic by combining membrane, PMS activation and electrochemical methods.

Oscillating electric field assisted nano-incised graphene kirigami for ultrahigh-performance water desalination membrane

Benefiting from the single-atom thickness, dense honeycomb structure, nano-size pores, and adjustable selection capability, graphene kirigami (GK) is expected to be a promising candidate for the membrane of water desalination. However, due to the low bending stiffness of the GK structure, the fluctuation in incision size and the accumulation of salt ions around the incisions always limit the GK membrane from higher water desalination efficiency. In this study, we adopted an oscillating electric field to improve the water desalination efficiency of nano-incised GK via molecular dynamic (MD) simulation. The results reveal that with the oscillating electric field's assistance, the water permeability of the GK membrane achieves 1351.6 L/m2/h/bar theoretically under the condition of 100 % salt rejection, 5.9–7.1 times higher than the reported nano-porous graphene membrane and 2–5 orders of magnitude higher than the existing reverse osmosis membranes. The oscillating electric field can enhance the water desalination efficiency of the proposed GK membranes mainly by alleviating the structural fluctuation of the GK membrane and dredging the permeation pathway for water molecules. The considerable potential of the oscillating electric field-assisted GK membrane reported by this study will attract great attention in the field of water separation and purification.

Flash brazing of SiC using Ag-Cu-Ti alloy at ultra-low temperature in air via electric field assistance

In this paper, the “flash brazing” of SiC is successfully achieved using Ag-Cu-Ti alloy in air for seconds at an ultra-low furnace temperature of 400 °C. The interface temperature reaches over 900 °C at an ultra-fast rate via the electric field assistance. The microstructure illustrates that SiC reacts with Ag-Cu-Ti alloy to form TiC to achieve the strong bonding of the joint, and the middle part of the joint is composed of silver-based solid solution and copper-based solid solution. With the increase of brazing holding time, the amount of copper-based solid solution in the joint gradually grows, and the shear strength of the joints first increases and then decreases. The maximum strength value of 70 MPa is obtained at 400 °C−10 A-60s. This method could help to improve the efficiency of ceramic bonding greatly.

Green extraction of phospholipids from ghee residue using pulsed electric field processing: Process optimisation and analysis of structural and compositional parameters

Process parameters were optimised using Taguchi orthogonal array design for extraction of phospholipids (PLs) from ghee residue (GR) with pulsed electric field (PEF) assistance. For higher PL yield and antioxidant activity, process voltage and time were observed to be significant factors. Optimised conditions were determined as 60 kV/cm voltage at 7.5 (v/w) solvent (water)‐to‐solid ratio for 5 min. Physical disruption of GR matrix due to PEF treatment was established through scanning electron micrographs. Lipidomic profile of the extract ascertained through liquid chromatography‐mass spectrophotometry (LC–MS) revealed multiple species of phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine in the resultant extract.

Mechanism of Targeted Regulation of Ovalbumin Epitopes by Pulsed Electric Field-Assisted Alcalase Treatment.

Egg is one of the eight major food allergens, and ovalbumin (OVA) is the most abundant allergenic protein in eggs. In this study, the effects of pulsed electric field (PEF)-assisted Alcalase hydrolysis on the spatial conformation and potential allergenicity of OVA were studied, and the mechanism of its inhibiting allergic reactions effect was revealed. PEF-assisted Alcalase hydrolysis increased the degree of hydrolysis, surface hydrophobicity, and free sulfhydryl group content. Moreover, the reduction in the α-helix content, fluorescence intensity, and disulfide bond content suggested that PEF promoted the OVA hydrolysis by Alcalase. Additionally, enzyme-linked immunosorbent assay data indicated that PEF-assisted Alcalase hydrolysis hindered OVA binding to immunoglobulins E and G1. Finally, based on bioinformatics combined with mass spectrometry, PEF-assisted Alcalase reduced OVA-induced allergic reactions by destroying epitopes in OVA. Overall, PEF technology further destroyed the epitopes of allergens by targeting the binding sites of substrates and enzymes to improve the affinity of enzymes and substrates, reducing allergic reactions.

Laser percussion drilling of transparent hard and brittle materials with ring-shaped electrodes

This paper presents an innovative approach to detect plasma induced by laser drilling in a laser processing system using an external sensing electric field. The system uses a sensing electrode to detect the plasma signal, which is then sent to the controller in real-time via an embedded signal sampling rate system. The system is capable of accurately sensing the pulse repetition rate from 0 to 500 kHz during laser processing, with a signal sampling rate of up to 1 MHz. The controller analyzes the plasma signal and adjusts the laser focus position by controlling the servo motor to achieve real-time detection of laser drilling. The paper compares several configurations of electric field assistance, including parallel type interdigitated electrodes, mask type interdigitated electrodes, ring shape electrodes, and parallel type interdigitated electrodes without a steel plate. The electric field strength and power line distribution of the electric field were simulated using the COMSOL Multiphysics finite element software, and the system was tested on sapphire and quartz glass. The experimental results showed that in the presence of the electric field, the opening diameter decreased by 8 % and 12.13 %, respectively, for sapphire and quartz glass, compared to the case without the electric field. Moreover, the exit diameter increased by more than 100 % and 49.79 %, the ring shape taper angle decreased by 23.31 % and 33.74 %, the machining time decreased by 66.22 % and more than 40 %, and the opening heat affected zone decreased by 24.45 % and more than 50 %, for sapphire and quartz glass, respectively.