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electrical field tuning of magneto-Raman scattering in monolayer graphene

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Nano Research 2015年第4期8卷 1139-1147页

作者： Xiaonan Shen Caiyu Qiu Bingchen Cao Chunxiao Cong Weihuang Yang Haomin Wang Ting Yu Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 637371 Singapore Singapore Wenzhou Institute of Biomaterials and Engineering Wenzhou 325001 China Department of Physics Faculty of Science National University of Singapore 117542 Singapore Singapore Graphene Research Center Faculty of Science National University of Singapore 117546 Singapore Singapore

In this work, we report the electrical field tuning of magneto-phonon resonance in monolayer graphene under magnetic fields up to 9 T. It is found that the carrier concentration can drastically affect the G （E2g） phonon response to a varying magnetic field through a pronounced magneto-phonon resonance （MPR）. In charge neutral or slightly doped monolayer graphene, both the energy and the line width of the E2g phonon show clear variation with magnetic fields. This is attributed to magneto-phonon resonance between magnetoexcitations and the E2g phonons. In contrast, when the Fermi level of the monolayer graphene is far away from the Dirac point, the G band shows weak magnetic dependence and exhibits a symmetric line-shape. This suggests that the magneto-phonon coupling around 4 T has been switched off due to the Pauli blocking of the inter-Landau level excitations. Moreover, the G band asymmetry caused by Fano resonance between excitonic many-body states and the E2g phonons is observed. This work offers a way to study the magnetoexcitation phonon interaction of materials through magneto-Raman spectroscopy with an external electrical field.

关键词： monolayer graphene magneto-phononresonance Raman electrical field suspended graphene

SIMULATION OF electrical field FOR THE FORMATION MECHANISM OF BIRD'S NEST PATTERNED STRUCTURES BY ELECTROSPINNING

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Chinese Journal of Polymer Science 2013年第3期31卷 514-520页

作者： Xiang-yu Ye Yi-ning Jin Xiao-jun Huang Lei Luo 徐志康 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University Institute of Advanced Digital Technology and Instrument Zhejiang University

In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird＇s Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechanism of Bird＇s Nest patterned architectures was proposed. Here, we use Ansoft Maxwell version 12 software （3D, electrostatic solver） to simulate the electrical field distribution of the electrospinning setup, and to clarify the rationality of proposed formation mechanism. Calculation results clearly show that the introduction of charged nanofibrous bundles would produce a similar patterned electrical field distribution, which definitely confirms the important role of surface residual charges. The proposed mechanism can be well extended to other polymer systems including polystyrene, poly（acrylonitrile-co-acrylic acid） and chitosan/poly（ethylene oxide）.

关键词： Electrospinning Patterned structures Finite element analysis electrical field Theoretical simulation.

Effect of electric field on the activity and quenching structure of liquid Cu-Al alloys

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Journal of University of Science and Technology Beijing 2005年第2期12卷 155-159页

作者： FajunGuo LingzhenLi YanbingZong DaqiangCang WenPan JunZhang MetallurgicalandEcologicalEngineeringSchool UniversityofScienceandTechnologyBeijingBeijing100083China

The activity coefficient of Al in molten Cu decreases with the increasing of electric current applied to the liquid alloy of Cu-0.2wt%Al. To investigate the mechanism, the quenching experimental results of the liquid Al-Cu alloy show that there is a re- markable change in structure, in which the solute congregates along the current direction especially for DC current. The mechanism of the activity coefficient change of Al in molten Cu-0.2wt%Al alloy treated by electrical field was discussed. Further, the results also provide an evidence for the short-range-ordered liquid metal.

关键词： electrical field activity liquid metal quenching structure liquid metal structure

Conversion of NO with a catalytic packedbed dielectric barrier discharge reactor

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Plasma Science and Technology 2017年第11期19卷 67-74页

作者： Xu CAO Weixuan ZHAO Renxi ZHANG Huiqi HOU Shanping CHEN Ruina ZHANG Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention （LAP^3） Institute of Environmental Science Fudan University Shanghai 200433 People＇s Republic of China Shanghai Institute for Design ＆ Research on Environmental Engineering Shanghai 200232 People＇s Republic of China

This paper discusses the conversion of nitric oxide（NO） with a low-temperature plasma induced by a catalytic packed-bed dielectric barrier discharge（DBD） reactor. Alumina oxide（Al2O3）,glass（SiO2） and zirconium oxide（ZrO2）, three different spherical packed materials of the same size, were each present in the DBD reactor. The NO conversion under varying input voltage and specific energy density, and the effects of catalysts（titanium dioxide（TiO2） and manganese oxide（Mn Ox） coated on Al2O3） on NO conversion were investigated. The experimental results showed that NO conversion was greatly enhanced in the presence of packed materials in the reactor, and the catalytic packed bed of Mn Ox/Al2O3 showed better performance than that of TiO2/Al2O3. The surface and crystal structures of the materials and catalysts were characterized through scanning electron microscopy analysis. The final products were clearly observed by a Fourier transform infrared spectrometer and provided a better understanding of NO conversion.

关键词： dielectric barrier discharge materials catalysts NO electrical field

Effect of applied electric fields on supralinear dendritic integration of interneuron

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Chinese Physics B 2024年第2期33卷 84-95页

作者：樊亚琴魏熙乐卢梅丽伊国胜 Tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China School of Information Technology Engineering Tianjin University of Technology and EducationTianjin 300222China

Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic ***,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic *** 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 *** 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 *** 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 *** 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 ***,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA ***,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.

关键词： GABAergic interneuron electrical field supralinear dendritic integration action potential generation

electrically charged: An effective mechanism for soft EOS supporting massive neutron star

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Science China(Physics,Mechanics & Astronomy) 2015年第10期58卷 100-106页

作者： JING ZhenZhen WEN DeHua ZHANG XiangDong School of Sciences South China University of Technology

The massive neutron star discoverer announced that strange particles, such as hyperons should be ruled out in the neutron star core as the soft Equation of State(EOS) can-not support a massive neutron star. However, many of the nuclear theories and laboratory experiments support that at high density the strange particles will appear and the corresponding EOS of super-dense matters will become soft. This situation promotes a challenge between the astro-observation and nuclear physics. In this work, we introduce an effective mechanism to answer this challenge, that is, if a neutron star is electrically charged, a soft EOS will be equivalently stiffened and thus can support a massive neutron star. By employing a representative soft EOS, it is found that in order to obtain an evident effect on the EOS and thus increasing the maximum stellar mass by the electrostatic field, the total net charge should be in an order of 1020 C. Moreover, by comparing the results of two kind of charge distributions, it is found that even for different distributions, a similar total charge:～2.3×1020C is needed to support a～2.0M⊙neutron star.

关键词： neutron star equation of state electrical field

Using artificial neural network to predict velocity of sound in liquid water as a function of ambient temperature, electrical and magnetic fields

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Journal of Ocean Engineering and Science 2016年第3期1卷 203-211页

作者： Hashem Nowruzi Hassan Ghassemi Department of Ocean Engineering Amirkabir University of Technology(Tehran Polytechnic)TehranIran

One of the main thermophysical properties of liquid water is velocity of ***,the effect of different externalities on velocity of sound in liquid water is not well ***,in current study,by designing an artificial neural network(ANN)velocity of sound in liquid water under different externalities is *** externalities are ambient temperature from 272.65 K to 348.43 K,different electrical fields in range of 0 V/m to 4.03E+9 V/m and magnetic fields in range of 0-10.0594 *** prepare of reference dataset for entry to ANN,numerical and experimental data as macroscopic reference data are extracted from microscopic characteristic of water HB *** order to achieve an appropriate ANN,ANN architecture sensitivity analysis is conducted by using an iterative *** procedure in the selected feed-forward back propagation ANN is done by hyperbolic transfer ***,Levenberg-Marquardt algorithm is utilized for the optimization *** output showed that the maximum MSE in prediction of velocity of sound is ***,the minimum of correlation coefficient in prediction of velocity of sound is *** on the ANNs outputs,weights and bias,an equation to predict of velocity of sound in liquid water under intended externalities is ***,according to weight sensitivity analysis input of electrical fields with 63%relative importance percentage has a grater impression on the response variable of velocity of sound in liquid water.©2016 Shanghai Jiaotong *** by Elsevier B.V.

关键词： Artificial neural network electrical field Magnetic field Velocity of sound Temperature

Improving Crude Oil Flow Using Graphene Flakes under an Applied Electric field

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2067-2081页

作者： Thaer Al-Jadir Laith S.Sabri Wafaa A.Kadhim Saja Mohsen Alardhi Raheek I.Ibrahim Environment Research Center University of Technology-IraqBaghdadIraq Chemical Engineering Department University of Technology-IraqBaghdadIraq Nanotechnology and Advanced Materials Research Center University of Technology-IraqBaghdadIraq Electromechanical Engineering Department University of Technology-IraqBaghdadIraq

Graphene flakes(GF)have been prepared and assessed as a material for improving flow in oil pipelines under the effect of an electric *** particular,different amounts of GFs have been considered in order to determine the optimal flow *** GFs were prepared from graphite foam,derived from the dehydration of sugar with a particle size of 500-600μm,which was dispersed in ethanol and exfoliated in a ball mill under a shear *** 15 h of exfoliation,sonication,and subsequent high-speed centrifugation at 3000 rpm,irregular-shaped GFs of 50-140 nm were produced and characterized using scanning electron microscopy,X-ray diffractometry,atomic force microscopy,and Raman *** prepared graphene sheets have been found to display excellent morphology and good graphitic *** on flow improvement were conducted using the central composite rotatable design method for three parameters:stimulation time(15,30,45,and 60 s),applied voltage(150,170,200,and 220 V),and concentration of the GFs(0,100,200,and 400 mg/L).The optimal conditions for improved crude oil flow were then determined using the STATISTICA and WinQSB software *** results have confirmed the effectiveness of the use of the prepared GFs as a flow improver for crude oil,where the flow improvement is essentially a result of a reduction in viscosity and suppression of friction in the crude oil system.

关键词： Graphene flakes flow improvement crude oil pipelines electrical field optimization

Tuning the Surface field by Embedding Cations into Metals to Direct the Reaction Pathway of CO_(2) Electroreduction

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CCS Chemistry 2024年第3期6卷 631-640页

作者： Pei Zhang Meng Zhou Shiqiang Liu Xueqing Xing Jiahao Yang Peng Chen Yaoyu Yin Yingying Cheng Xing Tong Jun Ma Qinggong Zhu Xiaofu Sun ZhongJun Chen Xinchen Kang Buxing Han Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesCenter for Carbon Neutral ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190 Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049 Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062 School of Chemistry University of Chinese Academy of SciencesBeijing 100049

The creation of universal strategies to affect the reaction route of the electroreduction of CO_(2) is ***,we report the first work to introduce cations into diverse metals such as Cu,Bi,In,and Sn via the electroreduction of related metallic oxides in quaternary ammonium surfactant *** to their physical adsorption,cations embedded into the electrodes have a more pronounced impact on the electrical field,which effectively influences the adsorption state of *** the increase of surface field,the hydrogen evolution reaction and*COOH route are significantly reduced,favouring the*OCHO pathway *** a result,hydrogen,CO,and C_(2+)products almost completely vanish at−0.5 V versus RHE in 0.1 M Na_(2)SO_(4)in an H-type cell after enough cations are embedded into the Cu electrode,and the faradaic efficiency of formate rises from 18.0%to 99.5%simultaneously.

关键词： CO_(2)electroreduction tuneable products electrical field reaction pathway cations embedding