Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is...Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is particularly significant in challenging coupled systems,such as CO_(2)photoreduction integrated with selective oxidation of toluene to benzaldehyde.However,developing such a system is quite challenging and often requires a precise design and engineering.Herein,we demonstrate a unique Ni-CdS@Ni(OH)_(2)heterojunction synthesized via an in-situ self-assembly method.Comprehensive mechanistic and theoretical investigations reveal that the NiCdS@Ni(OH)_(2)heterojunction induces dual electric fields(EFs):an intrinsic polarized electric-field within the CdS lattice from Ni doping and an interfacial electric-field from the growth of ultrathin nanosheets of Ni(OH)_(2)on NiCdS nanorods,enabling efficient spatial charge separation and enhanced redox potential.As proof of concept,the Ni-CdS@Ni(OH)_(2)heterojunction simultaneously exhibits outstanding bifunctional photocatalytic performance,producing CO at a rate of 427μmol g^(-1)h^(-1)and selectively oxidizing toluene to benzaldehyde at a rate of 1476μmol g^(-1)h^(-1)with a selectivity exceeding 85%.This work offers a promising strategy to optimize the utilization of photogenerated carriers in heterojunction photocatalysts,advancing synergistic photocatalytic redox systems.展开更多
The slow-proton-fast-electron process severely limits the catalytic efficiency of oxygen evolution reaction.A method is proposed to accelerate proton transfer by building up local electric fields.Modifying acetic,etha...The slow-proton-fast-electron process severely limits the catalytic efficiency of oxygen evolution reaction.A method is proposed to accelerate proton transfer by building up local electric fields.Modifying acetic,ethanedioic and propanetricarboxylic(C_(6)H_(8)O_(6))ligands on BiVO_(4)surface results in a potential difference between BiVO_(4)and ligands that generates a local electric field which serves as a driving force for proton transfer.Among the ligands,carrying the strongest electron-withdrawing ability,the modification of C_(6)H_(8)O_(6) forms the strongest local electric field and leads to the fastest proton transfer and the smallest thermodynamic overpotential.C_(6)H_(8)O_(6)-BiVO_(4)exhibits 3.5 times photocurrent density as high as that of pure BiVO_(4),which is 3.50 mA cm^(-2)at 1.23 VRHE.The onset potential of C_(6)H_(8)O_(6)-BiVO_(4)shifts negatively from 0.70 to 0.38 VRHE.The mechanism for OER transitions from thermodynamically high energy proton-coupled electron transfer to thermodynamically low energy electron transfer as proton transfer is accelerated.展开更多
We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric fields.By focusing on the multi-body interactions between ionic co...We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric fields.By focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these contexts.Our simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric fields.This work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems.展开更多
BACKGROUND Mesenchymal stem cells(MSCs)modulated by various exogenous signals have been applied extensively in regenerative medicine research.Notably,nanosecond pulsed electric fields(nsPEFs),characterized by short du...BACKGROUND Mesenchymal stem cells(MSCs)modulated by various exogenous signals have been applied extensively in regenerative medicine research.Notably,nanosecond pulsed electric fields(nsPEFs),characterized by short duration and high strength,significantly influence cell phenotypes and regulate MSCs differentiation via multiple pathways.Consequently,we used transcriptomics to study changes in messenger RNA(mRNA),long noncoding RNA(lncRNA),microRNA(miRNA),and circular RNA expression during nsPEFs application.AIM To explore gene expression profiles and potential transcriptional regulatory mechanisms in MSCs pretreated with nsPEFs.METHODS The impact of nsPEFs on the MSCs transcriptome was investigated through whole transcriptome sequencing.MSCs were pretreated with 5-pulse nsPEFs(100 ns at 10 kV/cm,1 Hz),followed by total RNA isolation.Each transcript was normalized by fragments per kilobase per million.Fold change and difference significance were applied to screen the differentially expressed genes(DEGs).Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to elucidate gene functions,complemented by quantitative polymerase chain reaction verification.RESULTS In total,263 DEGs were discovered,with 92 upregulated and 171 downregulated.DEGs were predominantly enriched in epithelial cell proliferation,osteoblast differentiation,mesenchymal cell differentiation,nuclear division,and wound healing.Regarding cellular components,DEGs are primarily involved in condensed chromosome,chromosomal region,actin cytoskeleton,and kinetochore.From aspect of molecular functions,DEGs are mainly involved in glycosaminoglycan binding,integrin binding,nuclear steroid receptor activity,cytoskeletal motor activity,and steroid binding.Quantitative real-time polymerase chain reaction confirmed targeted transcript regulation.CONCLUSION Our systematic investigation of the wide-ranging transcriptional pattern modulated by nsPEFs revealed the differential expression of 263 mRNAs,2 miRNAs,and 65 lncRNAs.Our study demonstrates that nsPEFs may affect stem cells through several signaling pathways,which are involved in vesicular transport,calcium ion transport,cytoskeleton,and cell differentiation.展开更多
The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterost...The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.展开更多
Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen ...Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen evolution reaction(HER).In this study,the intrinsically tunable internal bond electric field(IBEF)at the imine bonds of COFs was manipulated to cooperate with the internal molecular electric field(IMEF)induced by the donor-acceptor(D-A)structure for an efficient HER.The aligned orientation of IBEF and IMEF resulted in a remarkable H_(2) evolution rate of 57.3 mmol·g^(-1)·h^(-1)on TNCA,which was approximately 520 times higher than that of TCNA(0.11 mmol·g^(-1)·h^(-1))with the opposing electric field orientation.The superposition of the dual electric fields enables the IBEF to function as an accelerating field for electron transfer,kinetically facilitat-ing the migration of photogenerated electrons from D to A.Furthermore,theoretical calculations indicate that the inhomogeneous charge distribution at the C and N atoms in TNCA not only pro-vides a strong driving force for carrier transfer but also effectively hinders the return of free elec-trons to the valence band,improving the utilization of photoelectrons.This strategy of fabricating dual electric fields in COFs offers a novel approach to designing photocatalysts for clean energy synthesis.展开更多
Most advanced hydrogen evolution reaction(HER)catalysts show high activity under alkaline conditions.However,the performance deteriorates at a natural and acidic pH,which is often problematic in practical applications...Most advanced hydrogen evolution reaction(HER)catalysts show high activity under alkaline conditions.However,the performance deteriorates at a natural and acidic pH,which is often problematic in practical applications.Herein,a rhenium(Re)sulfide–transition-metal dichalcogenide heterojunc-tion catalyst with Re-rich vacancies(NiS_(2)-ReS_(2)-V)has been constructed.The optimized catalyst shows extraordinary electrocatalytic HER performance over a wide range of pH,with ultralow overpotentials of 42,85,and 122 mV under alkaline,acidic,and neutral conditions,respectively.Moreover,the two-electrode system with NiS_(2)-ReS_(2)-V1 as the cathode provides a voltage of 1.73 V at 500 mA cm^(-2),superior to industrial systems.Besides,the open-circuit voltage of a single Zn–H_(2)O cell with NiS_(2)-ReS_(2)-V1 as the cathode can reach an impressive 90.9% of the theoretical value,with a maximum power density of up to 31.6 mW cm^(-2).Moreover,it shows remarkable stability,with sustained discharge for approximately 120 h at 10 mA cm^(-2),significantly outperforming commercial Pt/C catalysts under the same conditions in all aspects.A series of systematic characterizations and theoretical calculations demonstrate that Re vacancies on the heterojunction interface would generate a stronger built-in electric field,which profoundly affects surface charge distribution and subsequently enhances HER performance.展开更多
Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic interneuron.However,it is still unclear how and why the EF-induc...Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic interneuron.However,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic inputs.Considering the key role of NMDA receptor-mediated supralinear dendritic integration in neuronal computations,we suppose that the applied EFs could functionally modulate interneurons’response via regulating dendritic integration.At first,we build a simplified multi-dendritic circuit model with inhomogeneous extracellular potentials,which characterizes the relationship among EF-induced spatial polarizations,dendritic integration,and somatic output.By performing model-based singular perturbation analysis,it is found that the equilibrium point of fast subsystem can be used to asymptotically depict the subthreshold input–output(sI/O)relationship of dendritic integration.It predicted that EF-induced strong depolarizations on the distal dendrites reduce the dendritic saturation output by reducing driving force of synaptic input,and it shifts the steep change of sI/O curve left by reducing stimulation threshold of triggering NMDA spike.Also,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA synapses.Furthermore,we identify the respective contribution of EF-regulated dendritic integration and EF-induced somatic polarization to an action potential generation and find that they have an antagonistic effect on AP generation due to the varied NMDA spike threshold under EF stimulation.展开更多
Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the in...Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the interfacial DMI originating from Rashba spin–orbit coupling(SOC) can be linearly tuned with strong external electric fields. In this work, we experimentally demonstrate that the strength of DMI exhibits rapid fluctuations, ranging from 10% to 30% of its original value, as a function of applied electric fields in Pt/Co/MgO heterostructures within the small field regime(< 10-2V/nm). Brillouin light scattering(BLS) experiments have been performed to measure DMI, and first-principles calculations show agreement with this observation, which can be explained by the variation in orbital hybridization at the Co/MgO interface in response to the weak electric fields. Our results on voltage control of DMI(VCDMI) suggest that research related to the voltage control of magnetic anisotropy for spin–orbit torque or the motion control of skyrmions might also have to consider the role of the external electric field on DMI as small voltages are generally used for the magnetoresistance detection.展开更多
Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s ...Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s show that.展开更多
The reported electrocaloric(EC)effect in ferroelectrics is poised for application in the next generation of solidstate refrigeration technology,exhibiting substantial developmental potential.This study introduces a no...The reported electrocaloric(EC)effect in ferroelectrics is poised for application in the next generation of solidstate refrigeration technology,exhibiting substantial developmental potential.This study introduces a novel and efficient EC effect strategy in(1-x)Pb(Lu_(1/2)Nb_(1/2))O_(3)-xPbTiO_(3)(PLN-xPT)ceramics for low electric-fielddriven devices.Phase-field simulations provide fundamental insights into thermally induced continuous phase transitions,guiding subsequent experimental investigations.A comprehensive composition/temperature-driven phase evolution diagram is constructed,elucidating the sequential transformation from ferroelectric(FE)to antiferroelectric(AFE)and finally to paraelectric(PE)phases for x=0.10-0.18 components.Direct measurements of EC performance highlight x=0.16 as an outstanding performer,exhibiting remarkable properties,including an adiabatic temperature change(ΔT)of 3.03 K,EC strength(ΔT/ΔE)of 0.08 K cm kV-1,and a temperature span(Tspan)of 31℃.The superior EC effect performance is attributed to the temperature-induced FE to AFE transition at low electric fields and diffusion phase transition behavior contributing to the wide Tspan.This work provides valuable insights into developing high-performance EC effect across broad temperature ranges through the strategic design of continuous phase transitions,offering a simplified and economical approach for advancing ecofriendly and efficient solid-state cooling technologies.展开更多
Liver cancer is one of the most malignant cancers. It is reported that 600 000 patients died from liver cancer every year. [1,2] Hepatocellular carcinoma (HCC) is a particular problem because symptoms are not evident ...Liver cancer is one of the most malignant cancers. It is reported that 600 000 patients died from liver cancer every year. [1,2] Hepatocellular carcinoma (HCC) is a particular problem because symptoms are not evident until the disease has progressed and hepatitis B, which is prominent specific regions of Asia, is a common precursor of the disease. There are many liver cancer展开更多
This experiment designed the pulsed electric fields （PEF） of high intensity of 100 kV· cm^-1 sterilization system. Fluorescent pseudomonas as target cell was operated 180 s in the PEF. By observing the differen...This experiment designed the pulsed electric fields （PEF） of high intensity of 100 kV· cm^-1 sterilization system. Fluorescent pseudomonas as target cell was operated 180 s in the PEF. By observing the difference of the bacteria before and after the disposal by TEM, it is found that the cell walls of the treated bacteria were broken. Irreversible perforations were formed on the cell membrane. The cell inclusions and cell fragments were leaked. The cell died as a result. The results showed that the PEF sterilization system designed can be used for liquid food sterilization experiments.展开更多
There is increasing public concern about biological interactions with and the potential health effects of low frequency electric and magnetic fields. Recently, the ICNIRP （International Commission on Non-Ionizing Rad...There is increasing public concern about biological interactions with and the potential health effects of low frequency electric and magnetic fields. Recently, the ICNIRP （International Commission on Non-Ionizing Radiation Protection） has published new exposure guidelines with regard to these fields. The aim of this paper is to demonstrate the calculation of the currents and electric fields induced in the human body by external electric fields at 60 Hz, using numerical human models of anatomically-realistic human bodies, and to compare those results with the basic restrictions proposed by the new guidelines. As a result, in the case that a human is exposed to an electric field of 1 kV/m at 60 Hz the short-circuit current of 18 μA flows though the ankles. Furthermore, the electric field of 40 mV/m in the nervous tissue of the adult model is induced by exposure to external electric fields at the reference level, which is enough smaller than the basic restrictions established in the ICNIRP guidelines for occupational exposure.展开更多
Langevin dynamics simulations have been performed to investigate the response of bi-disperse and strong polyacid chains grafted on an electrode to electric fields generated by opposite surface charges on the polyelect...Langevin dynamics simulations have been performed to investigate the response of bi-disperse and strong polyacid chains grafted on an electrode to electric fields generated by opposite surface charges on the polyelectrolyte （PE）-grafted electrode and a second parallel electrode. Simulation results clearly show that, under a negative external electric field, the longer grafted PE chains are more strongly stretched than the shorter ones in terms of the relative change in their respective brush heights. Whereas under a positive external electric field, the grafted shorter chains collapse more significantly than the longer ones. It was found that, under a positive external electric field, the magnitude of the total electric force acting on one shorter PE chain is larger than that on one longer PE chain, or vice versa. The effects of smeared and discrete charge distributions of grafted PE chains on the response of PE brushes to external electric fields were also examined.展开更多
With conjecture of fractional charge quantization (quantum dipole/multiple moments), Fourier transform stretching, twisting and twigging of an electron quanta and waver strings of electron quanta, the mathematical exp...With conjecture of fractional charge quantization (quantum dipole/multiple moments), Fourier transform stretching, twisting and twigging of an electron quanta and waver strings of electron quanta, the mathematical expressions for mesoscopic fractional electron fields in a cavity of viscous medium and the associated quantum dielectric susceptibility are developed. Agreement of this approach is experimentally evidenced on barite and Fanja site molecular sieves. These findings are in conformity with experimental results of 2012 Physics Nobel prize winning scientists, Serge Haroche and David J. Wineland especially for cavity quantum electro-dynamics electron and its associated mesoscopic electric fields. The mover electron quanta strings lead to warping of space and time following the behaviour of quantum electron dynamics.展开更多
Geometry and vibrational frequencies of the ground state of Si2O2 molecule are studied using density function theory （DFT） at the level of cc-pvtz and 6-311-k＋G^＊＊. It is found that the optimizing value by B31yp/...Geometry and vibrational frequencies of the ground state of Si2O2 molecule are studied using density function theory （DFT） at the level of cc-pvtz and 6-311-k＋G^＊＊. It is found that the optimizing value by B31yp/cc-pvtz is closer to the experimental data. The excited properties under different external electric fields are also investigated by the time-dependent-DFT method. Transitions from the ground state of Si2O2 molecule to the first singlet state under different external electric fields can take place more easily. The corresponding absorption spectral line is about 360 nm in wavelength and the excitation energy is about 3.4 eV.展开更多
Analytical expressions of electric fields inside and outside an anisotropic dielectric sphere are presented by transforming an anisotropic medium into an isotropic one based on the multi-scale transformation of electr...Analytical expressions of electric fields inside and outside an anisotropic dielectric sphere are presented by transforming an anisotropic medium into an isotropic one based on the multi-scale transformation of electromagnetic theory. The theoretical expressions are consistent with those in the literature. The inside electric field, the outside electric field and the angle between their directions are derived in detail. Numerical simulations show that the direction of the outside field influences the magnitude of the inside field, while the dielectric constant tensor greatly affects its direction.展开更多
This work presents a chemical kinetic analysis of different species involved in nitrogen-oxygen mixed gas induced by stationary corona discharge at room temperature and atmospheric pressure.This study takes into accou...This work presents a chemical kinetic analysis of different species involved in nitrogen-oxygen mixed gas induced by stationary corona discharge at room temperature and atmospheric pressure.This study takes into account twenty different chemical species participating in one hundred and seventy selected chemical reactions.The reaction rate coefficients are taken from the literature,and the density is analyzed by the continuity equation without the diffusion term.A large number of investigations considered the removal of NOx showing the effects of N,O and O3 radicals.The aim of the present simulation is to complete these studies by analysing various plasma species under different reduced electric fields in the range of 100-200 Td（1 Td=10-21 V·m^2）.In particular,we analyze the time evolution of depopulation（10^-9-10^-3s）of NOx.We have found that the depopulation rate of NO and NO2 is substantially affected by the rise of reduced electric field as it grows from 100 Td to 200 Td.This allows us to ascertain the important role played by the reduced electric field.展开更多
We develop a model of CA3 neurons embedded in a resistive array to mimic the effects of electric fields from a new perspective. Effects of DC and sinusoidal electric fields on firing patterns in CA3 neurons are invest...We develop a model of CA3 neurons embedded in a resistive array to mimic the effects of electric fields from a new perspective. Effects of DC and sinusoidal electric fields on firing patterns in CA3 neurons are investigated in this study. The firing patterns can be switched from no firing pattern to burst or from burst to fast periodic firing pattern with the increase of DC electric field intensity. It is also found that the firing activities are sensitive to the frequency and amplitude of the sinusoidal electric field. Different phase-locking states and chaotic firing regions are observed in the parameter space of frequency and amplitude. These findings are qualitatively in accordance with the results of relevant experimental and numerical studies. It is implied that the external or endogenous electric field can modulate the neural code in the brain. Furthermore, it is helpful to develop control strategies based on electric fields to control neural diseases such as epilepsy.展开更多
基金The authors sincerely appreciate funding from“Producing Hydrogen in Trentino-H2@TN”(PAT-Trento)through the research grant(SAP 40104237)Researchers Supporting Project number(RSP2025R399)King Saud University,Riyadh,Saudi Arabia.
文摘Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is particularly significant in challenging coupled systems,such as CO_(2)photoreduction integrated with selective oxidation of toluene to benzaldehyde.However,developing such a system is quite challenging and often requires a precise design and engineering.Herein,we demonstrate a unique Ni-CdS@Ni(OH)_(2)heterojunction synthesized via an in-situ self-assembly method.Comprehensive mechanistic and theoretical investigations reveal that the NiCdS@Ni(OH)_(2)heterojunction induces dual electric fields(EFs):an intrinsic polarized electric-field within the CdS lattice from Ni doping and an interfacial electric-field from the growth of ultrathin nanosheets of Ni(OH)_(2)on NiCdS nanorods,enabling efficient spatial charge separation and enhanced redox potential.As proof of concept,the Ni-CdS@Ni(OH)_(2)heterojunction simultaneously exhibits outstanding bifunctional photocatalytic performance,producing CO at a rate of 427μmol g^(-1)h^(-1)and selectively oxidizing toluene to benzaldehyde at a rate of 1476μmol g^(-1)h^(-1)with a selectivity exceeding 85%.This work offers a promising strategy to optimize the utilization of photogenerated carriers in heterojunction photocatalysts,advancing synergistic photocatalytic redox systems.
文摘The slow-proton-fast-electron process severely limits the catalytic efficiency of oxygen evolution reaction.A method is proposed to accelerate proton transfer by building up local electric fields.Modifying acetic,ethanedioic and propanetricarboxylic(C_(6)H_(8)O_(6))ligands on BiVO_(4)surface results in a potential difference between BiVO_(4)and ligands that generates a local electric field which serves as a driving force for proton transfer.Among the ligands,carrying the strongest electron-withdrawing ability,the modification of C_(6)H_(8)O_(6) forms the strongest local electric field and leads to the fastest proton transfer and the smallest thermodynamic overpotential.C_(6)H_(8)O_(6)-BiVO_(4)exhibits 3.5 times photocurrent density as high as that of pure BiVO_(4),which is 3.50 mA cm^(-2)at 1.23 VRHE.The onset potential of C_(6)H_(8)O_(6)-BiVO_(4)shifts negatively from 0.70 to 0.38 VRHE.The mechanism for OER transitions from thermodynamically high energy proton-coupled electron transfer to thermodynamically low energy electron transfer as proton transfer is accelerated.
基金supported by the Major Science and Technology Projects for Independent Innovation of China FAW Group Co., Ltd. (No. 20220301018GX)the National Natural Science Foundation of China (Nos. 9237210012, 22073094 and 21474109)+2 种基金the Science and Technology Development Program of Jilin Province (Nos. 20240602003RC and 20210402059GH)the State Key Laboratory of Molecular Engineering of Polymers (Fudan University) (No. K2023-08)the Program for Young Scholars in Regional Development of CAS
文摘We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric fields.By focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these contexts.Our simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric fields.This work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems.
基金Supported by the National Natural Science Foundation,China,No.82272568,81902247,and 32201013Natural Science Foundation of Shandong Province,China,No.ZR2021QH275+1 种基金Natural Science Foundation of Jinan City,China,No.202225070Guangdong Basic and Applied Basic Research Foundation,China,No.2022A1515220056.
文摘BACKGROUND Mesenchymal stem cells(MSCs)modulated by various exogenous signals have been applied extensively in regenerative medicine research.Notably,nanosecond pulsed electric fields(nsPEFs),characterized by short duration and high strength,significantly influence cell phenotypes and regulate MSCs differentiation via multiple pathways.Consequently,we used transcriptomics to study changes in messenger RNA(mRNA),long noncoding RNA(lncRNA),microRNA(miRNA),and circular RNA expression during nsPEFs application.AIM To explore gene expression profiles and potential transcriptional regulatory mechanisms in MSCs pretreated with nsPEFs.METHODS The impact of nsPEFs on the MSCs transcriptome was investigated through whole transcriptome sequencing.MSCs were pretreated with 5-pulse nsPEFs(100 ns at 10 kV/cm,1 Hz),followed by total RNA isolation.Each transcript was normalized by fragments per kilobase per million.Fold change and difference significance were applied to screen the differentially expressed genes(DEGs).Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to elucidate gene functions,complemented by quantitative polymerase chain reaction verification.RESULTS In total,263 DEGs were discovered,with 92 upregulated and 171 downregulated.DEGs were predominantly enriched in epithelial cell proliferation,osteoblast differentiation,mesenchymal cell differentiation,nuclear division,and wound healing.Regarding cellular components,DEGs are primarily involved in condensed chromosome,chromosomal region,actin cytoskeleton,and kinetochore.From aspect of molecular functions,DEGs are mainly involved in glycosaminoglycan binding,integrin binding,nuclear steroid receptor activity,cytoskeletal motor activity,and steroid binding.Quantitative real-time polymerase chain reaction confirmed targeted transcript regulation.CONCLUSION Our systematic investigation of the wide-ranging transcriptional pattern modulated by nsPEFs revealed the differential expression of 263 mRNAs,2 miRNAs,and 65 lncRNAs.Our study demonstrates that nsPEFs may affect stem cells through several signaling pathways,which are involved in vesicular transport,calcium ion transport,cytoskeleton,and cell differentiation.
基金supported by the National Natural Science Foundation of China(No.22269010,52231007,12327804,T2321003,22088101)the Jiangxi Provincial Natural Science Foundation(No.20224BAB214021)+1 种基金the Major Research Program of Jingdezhen Ceramic Industry(No.2023ZDGG002)the Ministry of Science and Technology of China(973 Project No.2021YFA1200600).
文摘The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.
文摘Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen evolution reaction(HER).In this study,the intrinsically tunable internal bond electric field(IBEF)at the imine bonds of COFs was manipulated to cooperate with the internal molecular electric field(IMEF)induced by the donor-acceptor(D-A)structure for an efficient HER.The aligned orientation of IBEF and IMEF resulted in a remarkable H_(2) evolution rate of 57.3 mmol·g^(-1)·h^(-1)on TNCA,which was approximately 520 times higher than that of TCNA(0.11 mmol·g^(-1)·h^(-1))with the opposing electric field orientation.The superposition of the dual electric fields enables the IBEF to function as an accelerating field for electron transfer,kinetically facilitat-ing the migration of photogenerated electrons from D to A.Furthermore,theoretical calculations indicate that the inhomogeneous charge distribution at the C and N atoms in TNCA not only pro-vides a strong driving force for carrier transfer but also effectively hinders the return of free elec-trons to the valence band,improving the utilization of photoelectrons.This strategy of fabricating dual electric fields in COFs offers a novel approach to designing photocatalysts for clean energy synthesis.
基金This study was supported by the National Research Foundation of Korea(NRF-2021R1A2C4001777,NRF-2022M3H4A1A04096482 and RS-2023-00229679),the National Natural Science Foundation of China(No.21965005,52363028)the Natural Science Foundation of Guangxi Province(2021GXNSFAA076001)the Guangxi Technology Base and Talent Subject(GUIKE AD20297039).
文摘Most advanced hydrogen evolution reaction(HER)catalysts show high activity under alkaline conditions.However,the performance deteriorates at a natural and acidic pH,which is often problematic in practical applications.Herein,a rhenium(Re)sulfide–transition-metal dichalcogenide heterojunc-tion catalyst with Re-rich vacancies(NiS_(2)-ReS_(2)-V)has been constructed.The optimized catalyst shows extraordinary electrocatalytic HER performance over a wide range of pH,with ultralow overpotentials of 42,85,and 122 mV under alkaline,acidic,and neutral conditions,respectively.Moreover,the two-electrode system with NiS_(2)-ReS_(2)-V1 as the cathode provides a voltage of 1.73 V at 500 mA cm^(-2),superior to industrial systems.Besides,the open-circuit voltage of a single Zn–H_(2)O cell with NiS_(2)-ReS_(2)-V1 as the cathode can reach an impressive 90.9% of the theoretical value,with a maximum power density of up to 31.6 mW cm^(-2).Moreover,it shows remarkable stability,with sustained discharge for approximately 120 h at 10 mA cm^(-2),significantly outperforming commercial Pt/C catalysts under the same conditions in all aspects.A series of systematic characterizations and theoretical calculations demonstrate that Re vacancies on the heterojunction interface would generate a stronger built-in electric field,which profoundly affects surface charge distribution and subsequently enhances HER performance.
基金Project supported by the National Natural Science Foundation of China(Grant No.62171312)the Tianjin Municipal Education Commission Scientific Research Project,China(Grant No.2020KJ114).
文摘Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic interneuron.However,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic inputs.Considering the key role of NMDA receptor-mediated supralinear dendritic integration in neuronal computations,we suppose that the applied EFs could functionally modulate interneurons’response via regulating dendritic integration.At first,we build a simplified multi-dendritic circuit model with inhomogeneous extracellular potentials,which characterizes the relationship among EF-induced spatial polarizations,dendritic integration,and somatic output.By performing model-based singular perturbation analysis,it is found that the equilibrium point of fast subsystem can be used to asymptotically depict the subthreshold input–output(sI/O)relationship of dendritic integration.It predicted that EF-induced strong depolarizations on the distal dendrites reduce the dendritic saturation output by reducing driving force of synaptic input,and it shifts the steep change of sI/O curve left by reducing stimulation threshold of triggering NMDA spike.Also,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA synapses.Furthermore,we identify the respective contribution of EF-regulated dendritic integration and EF-induced somatic polarization to an action potential generation and find that they have an antagonistic effect on AP generation due to the varied NMDA spike threshold under EF stimulation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61627813,62204018,and 61571023)the Beijing Municipal Science and Technology Project(Grant No.Z201100004220002)+2 种基金the National Key Technology Program of China(Grant No.2017ZX01032101)the Program of Introducing Talents of Discipline to Universities in China(Grant No.B16001)the VR Innovation Platform from Qingdao Science and Technology Commission.
文摘Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the interfacial DMI originating from Rashba spin–orbit coupling(SOC) can be linearly tuned with strong external electric fields. In this work, we experimentally demonstrate that the strength of DMI exhibits rapid fluctuations, ranging from 10% to 30% of its original value, as a function of applied electric fields in Pt/Co/MgO heterostructures within the small field regime(< 10-2V/nm). Brillouin light scattering(BLS) experiments have been performed to measure DMI, and first-principles calculations show agreement with this observation, which can be explained by the variation in orbital hybridization at the Co/MgO interface in response to the weak electric fields. Our results on voltage control of DMI(VCDMI) suggest that research related to the voltage control of magnetic anisotropy for spin–orbit torque or the motion control of skyrmions might also have to consider the role of the external electric field on DMI as small voltages are generally used for the magnetoresistance detection.
文摘Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s show that.
基金financially supported by the National Natural Science Foundation of China(Grant No.52261135548)the Key Research and Development Program of Shaanxi(Program No.2022KWZ-22)+2 种基金The research was made possible by Russian Science Foundation(Project No.23-42-00116)The equipment of the Ural Center for Shared Use“Modern nanotechnology”Ural Federal University(Reg.No.2968)which is supported by the Ministry of ScienceHigher Education RF(Project No.075-15-2021-677)was used.
文摘The reported electrocaloric(EC)effect in ferroelectrics is poised for application in the next generation of solidstate refrigeration technology,exhibiting substantial developmental potential.This study introduces a novel and efficient EC effect strategy in(1-x)Pb(Lu_(1/2)Nb_(1/2))O_(3)-xPbTiO_(3)(PLN-xPT)ceramics for low electric-fielddriven devices.Phase-field simulations provide fundamental insights into thermally induced continuous phase transitions,guiding subsequent experimental investigations.A comprehensive composition/temperature-driven phase evolution diagram is constructed,elucidating the sequential transformation from ferroelectric(FE)to antiferroelectric(AFE)and finally to paraelectric(PE)phases for x=0.10-0.18 components.Direct measurements of EC performance highlight x=0.16 as an outstanding performer,exhibiting remarkable properties,including an adiabatic temperature change(ΔT)of 3.03 K,EC strength(ΔT/ΔE)of 0.08 K cm kV-1,and a temperature span(Tspan)of 31℃.The superior EC effect performance is attributed to the temperature-induced FE to AFE transition at low electric fields and diffusion phase transition behavior contributing to the wide Tspan.This work provides valuable insights into developing high-performance EC effect across broad temperature ranges through the strategic design of continuous phase transitions,offering a simplified and economical approach for advancing ecofriendly and efficient solid-state cooling technologies.
基金supported by grants from the National Natural Science Foundation of China(3070078)a National S&T Major Project(2012ZX10002017)+1 种基金the National Basic Research Program of China(973 Program)(2009CB522403)Zhejiang Medical Research Funding(2008B079)
文摘Liver cancer is one of the most malignant cancers. It is reported that 600 000 patients died from liver cancer every year. [1,2] Hepatocellular carcinoma (HCC) is a particular problem because symptoms are not evident until the disease has progressed and hepatitis B, which is prominent specific regions of Asia, is a common precursor of the disease. There are many liver cancer
基金the Youth Science Fund of Heilongjiang Province (QC07C39)Postdoctoral Fund of Heilongjiang (LBH-Z06163)Science Research Fund of Northeast Agricultural University
文摘This experiment designed the pulsed electric fields （PEF） of high intensity of 100 kV· cm^-1 sterilization system. Fluorescent pseudomonas as target cell was operated 180 s in the PEF. By observing the difference of the bacteria before and after the disposal by TEM, it is found that the cell walls of the treated bacteria were broken. Irreversible perforations were formed on the cell membrane. The cell inclusions and cell fragments were leaked. The cell died as a result. The results showed that the PEF sterilization system designed can be used for liquid food sterilization experiments.
文摘There is increasing public concern about biological interactions with and the potential health effects of low frequency electric and magnetic fields. Recently, the ICNIRP （International Commission on Non-Ionizing Radiation Protection） has published new exposure guidelines with regard to these fields. The aim of this paper is to demonstrate the calculation of the currents and electric fields induced in the human body by external electric fields at 60 Hz, using numerical human models of anatomically-realistic human bodies, and to compare those results with the basic restrictions proposed by the new guidelines. As a result, in the case that a human is exposed to an electric field of 1 kV/m at 60 Hz the short-circuit current of 18 μA flows though the ankles. Furthermore, the electric field of 40 mV/m in the nervous tissue of the adult model is induced by exposure to external electric fields at the reference level, which is enough smaller than the basic restrictions established in the ICNIRP guidelines for occupational exposure.
基金supported by the National Natural Science Foundation of China(Grant No.21374052)
文摘Langevin dynamics simulations have been performed to investigate the response of bi-disperse and strong polyacid chains grafted on an electrode to electric fields generated by opposite surface charges on the polyelectrolyte （PE）-grafted electrode and a second parallel electrode. Simulation results clearly show that, under a negative external electric field, the longer grafted PE chains are more strongly stretched than the shorter ones in terms of the relative change in their respective brush heights. Whereas under a positive external electric field, the grafted shorter chains collapse more significantly than the longer ones. It was found that, under a positive external electric field, the magnitude of the total electric force acting on one shorter PE chain is larger than that on one longer PE chain, or vice versa. The effects of smeared and discrete charge distributions of grafted PE chains on the response of PE brushes to external electric fields were also examined.
文摘With conjecture of fractional charge quantization (quantum dipole/multiple moments), Fourier transform stretching, twisting and twigging of an electron quanta and waver strings of electron quanta, the mathematical expressions for mesoscopic fractional electron fields in a cavity of viscous medium and the associated quantum dielectric susceptibility are developed. Agreement of this approach is experimentally evidenced on barite and Fanja site molecular sieves. These findings are in conformity with experimental results of 2012 Physics Nobel prize winning scientists, Serge Haroche and David J. Wineland especially for cavity quantum electro-dynamics electron and its associated mesoscopic electric fields. The mover electron quanta strings lead to warping of space and time following the behaviour of quantum electron dynamics.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10774039)the Natural Science Foundation of Henan Province,China (Grant No. 092300410249)+1 种基金the Natural Science Foundation of the Education Bureau of Henan Province,China (Grant No. 2010A140008)the Foundation for University Young Core Instructors of Henan Province,China (Grant No. 2009GGJS-044)
文摘Geometry and vibrational frequencies of the ground state of Si2O2 molecule are studied using density function theory （DFT） at the level of cc-pvtz and 6-311-k＋G^＊＊. It is found that the optimizing value by B31yp/cc-pvtz is closer to the experimental data. The excited properties under different external electric fields are also investigated by the time-dependent-DFT method. Transitions from the ground state of Si2O2 molecule to the first singlet state under different external electric fields can take place more easily. The corresponding absorption spectral line is about 360 nm in wavelength and the excitation energy is about 3.4 eV.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 60741003 and 60871047)
文摘Analytical expressions of electric fields inside and outside an anisotropic dielectric sphere are presented by transforming an anisotropic medium into an isotropic one based on the multi-scale transformation of electromagnetic theory. The theoretical expressions are consistent with those in the literature. The inside electric field, the outside electric field and the angle between their directions are derived in detail. Numerical simulations show that the direction of the outside field influences the magnitude of the inside field, while the dielectric constant tensor greatly affects its direction.
文摘This work presents a chemical kinetic analysis of different species involved in nitrogen-oxygen mixed gas induced by stationary corona discharge at room temperature and atmospheric pressure.This study takes into account twenty different chemical species participating in one hundred and seventy selected chemical reactions.The reaction rate coefficients are taken from the literature,and the density is analyzed by the continuity equation without the diffusion term.A large number of investigations considered the removal of NOx showing the effects of N,O and O3 radicals.The aim of the present simulation is to complete these studies by analysing various plasma species under different reduced electric fields in the range of 100-200 Td（1 Td=10-21 V·m^2）.In particular,we analyze the time evolution of depopulation（10^-9-10^-3s）of NOx.We have found that the depopulation rate of NO and NO2 is substantially affected by the rise of reduced electric field as it grows from 100 Td to 200 Td.This allows us to ascertain the important role played by the reduced electric field.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61072012,60901035,and 50907044)
文摘We develop a model of CA3 neurons embedded in a resistive array to mimic the effects of electric fields from a new perspective. Effects of DC and sinusoidal electric fields on firing patterns in CA3 neurons are investigated in this study. The firing patterns can be switched from no firing pattern to burst or from burst to fast periodic firing pattern with the increase of DC electric field intensity. It is also found that the firing activities are sensitive to the frequency and amplitude of the sinusoidal electric field. Different phase-locking states and chaotic firing regions are observed in the parameter space of frequency and amplitude. These findings are qualitatively in accordance with the results of relevant experimental and numerical studies. It is implied that the external or endogenous electric field can modulate the neural code in the brain. Furthermore, it is helpful to develop control strategies based on electric fields to control neural diseases such as epilepsy.
