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Distribution of Electrical Field Energy for Conversion of Methane to C_2 Hydrocarbons via Dissymmetrical Electric Field Enhanced Plasma 被引量:2
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作者 Baowei Wang Genhui XU Hongwei Sun 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第2期115-121,共7页
Direct conversion of methane into C2 hydrocarbons through alternating current electric field enhanced plasma was studied under room temperature, atmospheric pressure and low power conditions. The distribution of elect... Direct conversion of methane into C2 hydrocarbons through alternating current electric field enhanced plasma was studied under room temperature, atmospheric pressure and low power conditions. The distribution of electrical field intensity and distribution of energy were calculated with software that was developed by us according to the charge simulation method. The results indicated that the energy of tip of electrode was 0.36 J/mm^3 and it was higher than the methane dissociation energy (0.0553 J/mm^3). The methane located at this area can be activated easily. The higher-energy particles produced by dissociation collided with molecules around them and initiated consecutive reactions between free radicals and molecules. The method was proved to be valided and could be taken as a basis for the electrical field study concerned. 展开更多
关键词 electrical field enhanced PLASMA intensity of electrical field distribution of energy
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An Analytical Model for the Surface Electrical Field Distribution and Optimization of Bulk-Silicon Double RESURF Devices
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作者 李琦 李肇基 张波 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1177-1182,共6页
A new 2D analytical model for the surface electrical field distribution and optimization of bulk-silicon double RESURF devices is presented. Based on the solution to the 2D Poisson's equation, the model gives the inf... A new 2D analytical model for the surface electrical field distribution and optimization of bulk-silicon double RESURF devices is presented. Based on the solution to the 2D Poisson's equation, the model gives the influence on the surface electrical field of the drain bias and structure parameters such as the doping concentration,the depth and the position of the p-top region, the thickness and the doping concentration of the drift region, and the substrate doping concentration. The dependence of breakdown voltage on the length and doping concentration of the drift region is also calculated. Further more,an effective way to gain the optimum high-voltage is also proposed. All analytical results are verified by simulation results obtained by MEDICI and previous experimental data,showing the validity of the model presented here. 展开更多
关键词 bulk-silicon double RESURF surface electrical field OPTIMIZATION
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A Novel Analytical Model for Surface Electrical Field Distribution and Optimization of TFSOI RESURF Devices 被引量:1
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作者 何进 张兴 +1 位作者 黄如 王阳元 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第4期402-408,共7页
A novel analytical model for the thin film silicon on insulator (TFSOI) reduced surface field (RESURF) devices has been proposed.Based on the 2-D Poisson equation solution,the analytical expressions for the surface po... A novel analytical model for the thin film silicon on insulator (TFSOI) reduced surface field (RESURF) devices has been proposed.Based on the 2-D Poisson equation solution,the analytical expressions for the surface potential and field distributions are derived.From this analysis,the optimum design condition for the maximum breakdown voltage is obtained.The dependence of the maximum breakdown voltage on the drift region length is examined and the relationship between the critical doping concentration and the front- and back- interface oxide layer thickness is discussed.The numerical simulation performed by the advanced semiconductor simulation tool,DESSIS-ISE,has been shown to support the analytical results. 展开更多
关键词 TFSOI RESURF devices surface electric field distribution potential profile breakdown voltage optimum design
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Early electrical field stimulation prevents the loss of spinal cord anterior horn motoneurons and muscle atrophy following spinal cord injury 被引量:10
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作者 Cheng Zhang Wei Rong +3 位作者 Guang-Hao Zhang Ai-Hua Wang Chang-Zhe Wu Xiao-Lin Huo 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第5期869-876,共8页
Our previous study revealed that early application of electrical field stimulation(EFS) with the anode at the lesion and the cathode distal to the lesion reduced injury potential, inhibited secondary injury and was ... Our previous study revealed that early application of electrical field stimulation(EFS) with the anode at the lesion and the cathode distal to the lesion reduced injury potential, inhibited secondary injury and was neuroprotective in the dorsal corticospinal tract after spinal cord injury(SCI). The objective of this study was to further evaluate the effect of EFS on protection of anterior horn motoneurons and their target musculature after SCI and its mechanism. Rats were randomized into three equal groups. The EFS group received EFS for 30 minutes immediately after injury at T_(10). SCI group rats were only subjected to SCI and sham group rats were only subjected to laminectomy. Luxol fast blue staining demonstrated that spinal cord tissue in the injury center was better protected; cross-sectional area and perimeter of injured tissue were significantly smaller in the EFS group than in the SCI group. Immunofluorescence and transmission electron microscopy showed that the number of spinal cord anterior horn motoneurons was greater and the number of abnormal neurons reduced in the EFS group compared with the SCI group. Wet weight and cross-sectional area of vastus lateralis muscles were smaller in the SCI group to in the sham group. However, EFS improved muscle atrophy and behavioral examination showed that EFS significantly increased the angle in the inclined plane test and Tarlov's motor grading score. The above results confirm that early EFS can effectively impede spinal cord anterior horn motoneuron loss, promote motor function recovery and reduce muscle atrophy in rats after SCI. 展开更多
关键词 nerve regeneration spinal cord injury electrical field stimulation anterior horn MOTONEURONS vastus lateralis muscle Tarlov's motor grading scale inclined plane test choline acetyltransferase transmission electron microscopy neural regeneration
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Electrical field-driven ripening profiles of colloidal suspensions
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作者 Zi-Rui Wang Wei-Jia Wen Li-Yu Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期496-501,共6页
Electrorheological(ER) fluid is a type of smart fluid whose shear yield stress relies on the external electrical field strength. The transition of ER fluid microstructure driven by the electrical field is the reason... Electrorheological(ER) fluid is a type of smart fluid whose shear yield stress relies on the external electrical field strength. The transition of ER fluid microstructure driven by the electrical field is the reason why viscosity changes.Experimentally, the transparent electrodes are used to investigate the column size distribution where an external electric field is applied to a colloidal suspension, i.e., ER fluid is increased. The coarsening profile of ER suspensions is strongly related to electrical field strength, but it is insensitive to particle size. In addition, in a low field range the shear stress corresponding to the mean column diameter is studied and they are found to satisfy a power law. However, this dependence is invalid when the field strength surpasses a threshold value. 展开更多
关键词 electrorheological fluid electrical field coarsening structure
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Influence of Electrical Field Distortions Induced by Water Droplets on the Contamination Characteristics of an Insulator
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作者 Yukun Lv Yuechi Wang Jiawen Wang 《Fluid Dynamics & Materials Processing》 EI 2021年第5期971-987,共17页
When separated water droplets condense on the surface of a composite insulator,the electrical field on the insulator surface is distorted.In turn,such distortions change the trajectories of pollution particles.In this... When separated water droplets condense on the surface of a composite insulator,the electrical field on the insulator surface is distorted.In turn,such distortions change the trajectories of pollution particles.In this study,the COMSOL software is used to simulate such a process for the FXBW4-10/100 composite insulator with or without water droplets condensation under a 10 kV DC voltage.The influence of the wind speed and particles concentration on the contamination characteristics of the considered 110 kV insulator is analyzed.The results show that:1)in the presence of water droplets on the insulator surface,the ratio of electrical field force and gravity acting on the particles is large;2)the contamination on the insulator surface increases with the wind speed;3)when the wind speed is small,the relationship between the contamination amount and the pollution concentration is essentially linear. 展开更多
关键词 Water droplets composite insulator numerical simulation electrical field distortion contamination characteristic
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Self-sustained firing activities of the cortical network with plastic rules in weak AC electrical fields
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作者 秦迎梅 王江 +3 位作者 门聪 赵佳 魏熙乐 邓斌 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期604-610,共7页
Both external and endogenous electrical fields widely exist in the environment of cortical neurons. The effects of a weak alternating current (AC) field on a neural network model with synaptic plasticity are studied... Both external and endogenous electrical fields widely exist in the environment of cortical neurons. The effects of a weak alternating current (AC) field on a neural network model with synaptic plasticity are studied. It is found that self-sustained rhythmic firing patterns, which are closely correlated with the cognitive functions, are significantly modified due to the self-organizing of the network in the weak AC field. The activities of the neural networks are affected by the synaptic connection strength, the exterrtal stimuli, and so on. In the presence of learning rules, the synaptic connections can be modulated by the external stimuli, which will further enhance the sensitivity of the network to the external signal. The properties of the external AC stimuli can serve as control parameters in modulating the evolution of the neural network. 展开更多
关键词 spike-timing-dependent plasticity (STDP) weak electrical field rhythmic activity
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Electrical fields and the promotion of endogenous angiogenesis in a rat spinal cord injury model
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作者 Yang Shao Bo Xiao +3 位作者 Haihan Ma Jie Gao Qidong Yang Min Zhao 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第14期1091-1095,共5页
BACKGROUND: Previous studies have shown that direct current electrical fields affect development and growth of human microvascular endothelial cells, but the role of electrical fields on promoting angiogenesis in tis... BACKGROUND: Previous studies have shown that direct current electrical fields affect development and growth of human microvascular endothelial cells, but the role of electrical fields on promoting angiogenesis in tissues following spinal cord injury remains poorly understood. OBJECTIVE: To determine the effects of electrical fields on angiogenesis and spinal cord repair following traumatic spinal cord injury in rats. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Chongqing Key Laboratory of Neurology, Affiliated Hospital of Chongqing Medical University, China from September 2007 to August 2008. MATERIALS: Hydrogen blood flow detector (Soochow University Medical Instrument, China), Power Lab System (AD Instruments, Colorado Springs, CO, USA) and mouse anti-vascular endothelial growth factor (VEGF) monoclonal antibody (Sigma-Aldrich, St. Louis, MO, USA) were used in this study. METHODS: A total of 60 healthy, adult, Sprague Dawley rats were equally and randomly assigned to sham-surgery, model, and electrical field groups. The Allen's weight-drop method was used to induce complete spinal cord injury in the model and electrical field groups. Rats in the electrical field group were implanted with silver needles and electrical fields (350 V/m) were applied following traumatic injury. MAIN OUTCOME MEASURES: Latency of somatosensory-evoked potential was detected and spinal cord blood flow was measured by hydrogen blood flow detector. Microvascular density was determined by histological analysis. VEGF expression in the spinal cord was observed by immunohistochemical staining. RESULTS: Recovery of spinal cord blood flow was significantly increased in the electrical field group (at 1, 2, 4, 8, and 24 days after injury) compared with the model group (P 〈 0.05 or P 〈 0.01). Latency of P1 waves in somatosensory-evoked potential of electrical field group (at 1,2, 4, 8, and 24 days after injury) was significantly shorter than the model group (P 〈 0.05 or P 〈 0.01). Microvascular density and VEGF expression were greater in the electrical field group compared with the model group at 24 days after injury (P 〈 0.01). CONCLUSION: Electrical fields (350 V/m) promoted angiogenesis within injured rat tissue following spinal cord injury and improved spinal cord function. Electrical fields could help to ameliorate spinal cord injury. The mechanisms of action could be related to increased VEGF expression. 展开更多
关键词 ANGIOGENESIS electric fields spinal cord injury spinal cord blood flow vascular endothelial growth factor neural regeneration
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Photoionization microscopy of Rydberg hydrogen atom in a non-uniform electrical field
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作者 程绍昊 王德华 +1 位作者 陈召杭 陈强 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期191-200,共10页
In this paper,we investigate the photoionization microscopy of the Rydberg hydrogen atom in a gradient electric field for the first time.The observed oscillatory patterns in the photoionization microscopy are explaine... In this paper,we investigate the photoionization microscopy of the Rydberg hydrogen atom in a gradient electric field for the first time.The observed oscillatory patterns in the photoionization microscopy are explained within the framework of the semiclassical theory,which can be considered as a manifestation of interference between various electron trajectories arriving at a given point on the detector plane.In contrast with the photoionization microscopy in the uniform electric field,the trajectories of the ionized electron in the gradient electric field will become chaotic.An infinite set of different electron trajectories can arrive at a given point on the detector plane,which makes the interference pattern of the electron probability density distribution extremely complicated.Our calculation results suggest that the oscillatory pattern in the electron probability density distribution depends sensitively on the electric field gradient,the scaled energy and the position of the detector plane.Through our research,we predict that the interference pattern in the electron probability density distribution can be observed in an actual photoionization microscopy experiment once the external electric field strength and the position of the electron detector plane are reasonable.This study provides some references for the future experimental research on the photoionization microscopy of the Rydberg atom in the non-uniform external fields. 展开更多
关键词 photoionization microscopy gradient electric field semiclassical theory
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Effect of applied electric fields on supralinear dendritic integration of interneuron
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作者 樊亚琴 魏熙乐 +1 位作者 卢梅丽 伊国胜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期84-95,共12页
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
关键词 GABAergic interneuron electrical field supralinear dendritic integration action potential generation
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Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response 被引量:1
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作者 Xiaojun Zeng Xiao Jiang +2 位作者 Ya Ning Yanfeng Gao Renchao Che 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期453-473,共21页
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
关键词 Semiconductor-semiconductor-metal heterostructure Semiconductor junctions Mott-Schottky junctions Built-in electric field Electromagnetic wave absorption
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Effects of vacancy and external electric field on the electronic properties of the MoSi_(2)N_(4)/graphene heterostructure 被引量:1
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作者 梁前 罗祥燕 +3 位作者 钱国林 王远帆 梁永超 谢泉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期542-550,共9页
Recently,the newly synthesized septuple-atomic layer two-dimensional(2D)material MoSi_(2)N_(4)(MSN)has attracted attention worldwide.Our work delves into the effect of vacancies and external electric fields on the ele... Recently,the newly synthesized septuple-atomic layer two-dimensional(2D)material MoSi_(2)N_(4)(MSN)has attracted attention worldwide.Our work delves into the effect of vacancies and external electric fields on the electronic properties of the MSN/graphene(Gr)heterostructure using first-principles calculation.We find that four types of defective structures,N-in,N-out,Si and Mo vacancy defects of monolayer MSN and MSN/Gr heterostructure are stable in air.Moreover,vacancy defects can effectively modulate the charge transfer at the interface of the MSN/Gr heterostructure as well as the work function of the pristine monolayer MSN and MSN/Gr heterostructure.Finally,the application of an external electric field enables the dynamic switching between n-type and p-type Schottky contacts.Our work may offer the possibility of exceeding the capabilities of conventional Schottky diodes based on MSN/Gr heterostructures. 展开更多
关键词 MoSi_(2)N_(4) vacancy defects external electric field Schottky contacts
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Superposition of dual electric fields in covalent organic frameworks for efficient photocatalytic hydrogen evolution
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作者 Chao Li Shuo Wang +8 位作者 Yuan Liub Xihe Huang Yan Zhuang Shuhong Wu Ying Wang Na Wen Kaifeng Wu Zhengxin Ding Jinlin Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期164-175,共12页
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
关键词 Covalent organic framework Internal molecular electric field Internal bond electric field PHOTOCATALYSIS Hydrogen evolution
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Influence of filler characteristics on particle removal in fluid catalytic cracking slurry under an alternating electric field
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作者 Qiang Li Hui-Zhen Yang +3 位作者 Can Yang Qing-Zhu Qiu Wei-Wei Xu Zhao-Zeng Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2102-2111,共10页
The characteristics of the packing material under an alternating electric field are an important factor in the removal of FCCS particles.In this study,the electric field distribution of a separation unit consisting of... The characteristics of the packing material under an alternating electric field are an important factor in the removal of FCCS particles.In this study,the electric field distribution of a separation unit consisting of packed spheres under an alternating electric field is simulated,and the movement mechanism of catalyst particles is analysed.An"effective contact point"model is derived to predict the adsorption of filler contact points on catalyst particles under the alternating electric field,and the model is validated by simulations and experiments.The numerical calculation and experimental results indicate that the electrical properties of the filler spheres,the filler angleθ,and the frequency f of the alternating electric field affect the adsorption of catalyst particles.As the frequency of the electric field increases,the particle removal efficiency of the high-conductivity filler(silicon carbide)increases and then settles,and the separation efficiency of the low-conductivity filler(glass,zirconia)is not sensitive to the change in electric field frequency. 展开更多
关键词 Fluid catalyticcracking slurry(FCCS) PARTICLE AC electric field FILLERS REMOVAL
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Coexisting fast–slow dendritic traveling waves in a 3D-array electric field coupled neuronal network
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作者 魏熙乐 任泽宇 +2 位作者 卢梅丽 樊亚琴 常思远 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期614-626,共13页
Coexistence of fast and slow traveling waves without synaptic transmission has been found in hhhippocampal tissues,which is closely related to both normal brain activity and abnormal neural activity such as epileptic ... Coexistence of fast and slow traveling waves without synaptic transmission has been found in hhhippocampal tissues,which is closely related to both normal brain activity and abnormal neural activity such as epileptic discharge. However, the propagation mechanism behind this coexistence phenomenon remains unclear. In this paper, a three-dimensional electric field coupled hippocampal neural network is established to investigate generation of coexisting spontaneous fast and slow traveling waves. This model captures two types of dendritic traveling waves propagating in both transverse and longitude directions: the N-methyl-D-aspartate(NMDA)-dependent wave with a speed of about 0.1 m/s and the Ca-dependent wave with a speed of about 0.009 m/s. These traveling waves are synaptic-independent and could be conducted only by the electric fields generated by neighboring neurons, which are basically consistent with the in vitro data measured experiments. It is also found that the slow Ca wave could trigger generation of fast NMDA waves in the propagation path of slow waves whereas fast NMDA waves cannot affect the propagation of slow Ca waves. These results suggest that dendritic Ca waves could acted as the source of the coexistence fast and slow waves. Furthermore, we also confirm the impact of cellular spacing heterogeneity on the onset of coexisting fast and slow waves. The local region with decreasing distances among neighbor neurons is more liable to promote the onset of spontaneous slow waves which, as sources, excite propagation of fast waves. These modeling studies provide possible biophysical mechanisms underlying the neural dynamics of spontaneous traveling waves in brain tissues. 展开更多
关键词 hippocampal network EPILEPTIFORM dendritic oscillation traveling wave electric field coupling
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Enabling built-in electric fields on rhenium-vacancy-rich heterojunction interfaces of transition-metal dichalcogenides for pH-universal efficient hydrogen and electric energy generation
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作者 Benzhi Wang Lixia Wang +3 位作者 Ji Hoon Lee Tayirjan Taylor Isimjan Hyung Mo Jeong Xiulin Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期195-209,共15页
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
关键词 built-in electric field ELECTROCATALYSTS hydrogen evolution reaction self-powered system water splitting Zn-H_(2)O cell
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The action mechanism of the work done by the electric field force on moving charges to stimulate the emergence of carrier generation/recombination in a PN junction
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作者 Lingyun GUO Yizhan YANG +1 位作者 Wanli YANG Yuantai HU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1001-1014,共14页
It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron curren... It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron current),which was previously misinterpreted as solely a Joule heating effect.We clarify that it is exactly the work done by the electric field force on the moving charges to stimulate the emergence of non-equilibrium carriers,which triggers the novel physical phenomena.As regards to Joule heat,we point out that it should be calculated from Ohm’s law,rather than simply from the product of the current and the electric field.Based on this understanding,we conduct thorough discussion on the role of the electric field force in the process of carrier recombination and carrier generation.The thermal effects of carrier recombination and carrier generation followed are incorporated into the thermal equation of energy.The present study shows that the exothermic effect of carrier recombination leads to a temperature rise at the PN interface,while the endothermic effect of carrier generation causes a temperature reduction at the interface.These two opposite effects cause opposite heat flow directions in the PN junction under forward and backward bias voltages,highlighting the significance of managing device heating phenomena in design considerations.Therefore,this study possesses referential significance for the design and tuning on the performance of piezotronic devices. 展开更多
关键词 piezoelectric semiconductor(PS) work done by electric field force thermal effect piezotronic device resistivity conductivity
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Electric field and force characteristic of dust aerosol particles on the surface of high-voltage transmission line
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作者 刘滢格 李兴财 +2 位作者 王娟 马鑫 孙文海 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期368-378,共11页
High-voltage transmission lines play a crucial role in facilitating the utilization of renewable energy in regions prone to desertification. The accumulation of atmospheric particles on the surface of these lines can ... High-voltage transmission lines play a crucial role in facilitating the utilization of renewable energy in regions prone to desertification. The accumulation of atmospheric particles on the surface of these lines can significantly impact corona discharge and wind-induced conductor displacement. Accurately quantifying the force exerted by particles adhering to conductor surfaces is essential for evaluating fouling conditions and making informed decisions. Therefore, this study investigates the changes in electric field intensity along branched conductors caused by various fouling layers and their resulting influence on the adhesion of dust particles. The findings indicate that as individual particle size increases, the field strength at the top of the particle gradually decreases and eventually stabilizes at approximately 49.22 k V/cm, which corresponds to a field strength approximately 1.96 times higher than that of an unpolluted transmission line. Furthermore,when particle spacing exceeds 15 times the particle size, the field strength around the transmission line gradually decreases and approaches the level observed on non-adhering surface. The electric field remains relatively stable. In a triangular arrangement of three particles, the maximum field strength at the tip of the fouling layer is approximately 1.44 times higher than that of double particles and 1.5 times higher compared to single particles. These results suggest that particles adhering to the transmission line have a greater affinity for adsorbing charged particles. Additionally, relevant numerical calculations demonstrate that in dry environments, the primary adhesion forces between particles and transmission lines follow an order of electrostatic force and van der Waals force. Specifically, at the minimum field strength, these forces are approximately74.73 times and 19.43 times stronger than the gravitational force acting on the particles. 展开更多
关键词 high-voltage current electric field aerosol particles force characteristic
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Mild polarization electric field in ultra-thin BN-Fe-graphene sandwich structure for efficient nitrogen reduction
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作者 Ziyuan Xiu Wei Mu +1 位作者 Xin Zhou Xiaojun Han 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期126-137,共12页
The electrocatalytic N_(2)reduction reaction(NRR)is expected to supersede the traditional Haber-Bosch technology for NH3 production under ambient conditions.The activity and selectivity of electrochemical NRR are rest... The electrocatalytic N_(2)reduction reaction(NRR)is expected to supersede the traditional Haber-Bosch technology for NH3 production under ambient conditions.The activity and selectivity of electrochemical NRR are restricted to a strong polarized electric field induced by the catalyst,correct electron transfer direction,and electron tunneling distance between bare electrode and active sites.By coupling the chemical vapor deposition method with the poly(methyl methacylate)-transfer method,an ultrathin sandwich catalyst,i.e.,Fe atoms(polarized electric field layer)sandwiched between ultrathin(within electron tunneling distance)BN(catalyst layer)and graphene film(conducting layer),is fabricated for electrocatalytic NRR.The sandwich catalyst not only controls the transfer of electrons to the BN surface in the correct direction under applied voltage but also suppresses hydrogen evolution reaction by constructing a neutral polarization electric field without metal exposure.The sandwich electrocatalyst NRR system achieve NH3 yield of 8.9μg h^(−1)cm^(−2)and Faradaic Efficiency of 21.7%.The N_(2)adsorption,activation,and polarization electric field changes of three sandwich catalysts(BN-Fe-G,BN-Fe-BN,and G-Fe-G)during the electrocatalytic NRR are investigated by experiments and density functional theory simulations.Driven by applied voltage,the neutral polarized electric field induced by BN-Fe-G leads to the high activity of electrocatalytic NRR. 展开更多
关键词 Ultra-thin BN Fe doping BN-Fe-graphene Mild polarization electric field Nitrogen reduction reaction
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A new electric field mill array with each of the mill’s rotor controlled precisely by a GPS module:Equipment and initial results
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作者 Kozo Yamashita Hironobu Fujisaka +4 位作者 DaoHong Wang Hiroyuki Iwasaki Kazuo Yamamoto Koichiro Michimoto Masashi Hayakawa 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期423-435,共13页
We have newly designed an electrostatic sensor,called an electric field mill(EFM),to simplify the estimation of the charge position and charge amount transferred by lightning discharges.It is necessary for this remote... We have newly designed an electrostatic sensor,called an electric field mill(EFM),to simplify the estimation of the charge position and charge amount transferred by lightning discharges.It is necessary for this remote estimation of the transferred charge to measure electric field changes caused by charge loss at the time of a lightning strike at multiple locations.For multiple-station measurement of electric field changes,not only speed but also phase for exposure and shielding of the sensing plates inside each EFM of the array should be synchronized to maintain the sensitivities of the deployed instruments.Currently,there is no such EFM with specified speed and phase control performance of the rotary part.Thus,we developed a new EFM in which the rotary mechanism was controlled consistently to within 3%error by a GPS module.Five EFMs had been distributed in the Hokuriku area of Japan during the winter season of 2022-2023 for a test observation.Here we describe the design and a simple calibration method for our new EFM array.Data analysis method based on the assumption of a simple monopole charge structure is also summarized.For validation,locations of assumed point charges were compared with three-dimensional lightning mapping data estimated by radio observations in the MF-HF bands.Initial results indicated the validity to estimate transferred charge amounts and positions of winter cloud-to-ground lightning discharges with our new EFM array. 展开更多
关键词 LIGHTNING electrostatic field electric field mill electric field change
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