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Quantum and Transport Mobilities of a Two-Dimensional Electron Gas in the Presence of the Rashba Spin-Orbit Interaction

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Journal of Semiconductors 2006年第2期27卷 204-217页

作者： Xu Wen department of Theoretical Physics Research School of Physical Sciences and Engineering Australian National University Canberra ACT 0200 Australia Institute of Solid State Physics Chinese Academy of Sciences ttefei 230031 China

A systematic theoretical approach is developed to study the electronic and transport properties of a two-dimensional electron gas (2DEG) in the presence of spin-orbit interactions induced by the Rashba *** standard random-phase approximation is employed to calculate the screening length caused by electron-electron interaction in different transition *** quantum and transport mobilities in different spin branches are evaluated using the momentum-balance equation derived from the Boltzmann equation,in which the electron interactions with both the remote and background impurities are taken into account in an InAlAs/InGaAs heterojunction at low-temperatures.

关键词：半导体技术电子传输量子 2DEG 交互作用

First principles study of post-boron carbide phases with icosahedra broken

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Chinese Physics B 2020年第10期29卷 214-221页

作者： Ming-Wei Chen Zhao Liang Mei-Ling Liu Uppalapati Pramod Kumar Chao Liu Tong-Xiang Liang Faculty of Materials Metallurgy and chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

Boron carbide (B4C) is a rhombic structure composed of icosahedra and atomic chains, which has an important application in armored materials. The application of B4C under super high pressure without failure is a hot spot of research. Previous studies have unmasked the essential cause of B4C failure, i.e., its structure will change subjected to impact, especially under the non-hydrostatic pressure and shear stress. However, the change of structure has not been clearly understood nor accurately determined. Here in this paper, we propose several B4C polymorphs including B4C high pressure phases with non-icosahedra, which are denoted as post-B4C and their structures are formed due to icosahedra broken and may be obtained through high pressure and high temperature (HPHT). The research of their physical properties indicates that these B4C polymorphs have outstanding mechanical and electrical properties. For instance, aP10, mC10, mP20, and oP10-B4C are conductive superhard materials. We hope that our research will enrich the cognition of high pressure structural deformation of B4C and broaden the application scope of B4C.

关键词： boron carbide structural transformation icosahedra broken physical properties first principles

Surface Functionalization of Microporous Polypropylene Membrane with Polyols for Removal of Boron Acid from Aqueous Solution

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Chinese Journal of Chemical Engineering 2014年第1期22卷 11-18页

作者：周蓉狄玲王苍方艳吴健徐志康 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University department of chemistry Zhejiang University

Affinity membranes are fabricated for boric acid removal by the surface functionalization of microporous polypropylene membrane(MPPM)with lactose-based *** affinity is based on specific complexation between boric acid and saccharide polyols.A photoinduced grafting-chemical reaction sequence was used to prepare these affinity ***(2-aminoethyl methacrylate hydrochloride)[poly(AEMA)]was grafted on the surfaces of MPPM by UV-induced graft *** in the membrane pores was visualized by dying the cross-section of poly(AEMA)-grafted MPPM with fluorescein disodium and imaging with confocal laser scanning *** is concluded that lactose ligands can be covalently immobilized on the external surface and in the pores by the subsequent coupling of poly(AEMA)with lactobionic acid(LA).physical and chemical properties of the affinity membranes were characterized by field emission scanning electron microscopy and Fourier Transform Infrared/Attenuated Total Refraction spectroscopy(FT-IR/ATR).3-Aminophenyl boric acid(3-APBA)was removed from aqueous solution by a single piece of lactose-functionalized MPPM in a dynamic filtration *** results show that the 3-APBA removal reaches an optimal efficiency(39.5%)under the alkaline condition(pH9.1),which can be improved by increasing the immobilization density of *** of these affinity membranes can be easily realized through acid-base washing because the complexation of boric acid and saccharide polyol is reversible.

关键词： surface functionalization affinity membrane microporous polypropylene membrane boron removal polyols

Anti-Overturning Fully Symmetrical Triboelectric Nanogenerator Based on an Elliptic Cylindrical Structure for All-Weather Blue Energy Harvesting

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Nano-Micro Letters 2022年第7期14卷 342-353页

作者： Dujuan Tan Qixuan Zeng Xue Wang Songlei Yuan Yanlin Luo Xiaofang Zhang Liming Tan Chenguo Hu Guanlin Liu department of Applied Physics State Key Laboratory of Power Transmission Equipment&System Security and New TechnologyChongqing UniversityChongqing 400044People’s Republic of China Center On Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanningGuangxi 530004People’s Republic of China

Triboelectric nanogenerators(TENGs) have shown promising potential for large-scale blue energy harvesting. However, the lack of reasonable designs has largely hindered TENG from harvesting energy from both rough and tranquil seas. Herein, a fully symmetrical triboelectric nanogenerator based on an elliptical cylindrical structure(EC-TENG) is proposed for all-weather blue energy harvesting. The novel elliptical cylindrical shell provides a unique selfstability, high sensitivity to wave triggering, and most importantly, an anti-overturning capability for the EC-TENG. Moreover, benefiting from its internal symmetrical design, the EC-TENG can produce energy normally, even if it was overturned under a rude oscillation in the rough seas, which distinguishes this work from previous reported TENGs. The working mechanism and output performance are systematically studied. The as-fabricated EC-TENG is capable of lighting 400 light-emitting diodes and driving small electronics. More than that, an automatic monitoring system powered by the EC-TENG can also monitor the water level in real-time and provide an alarm if necessary. This work presents an innovative and reliable approach toward all-weather wave energy harvesting in actual marine environments.

关键词： Anti-overturning Fully symmetrical Elliptic cylindrical Triboelectric nanogenerator Wave energy

Insight into relationship between composition,thickness and electrochemistry behavior of oxide film formed on TA15under different potentials in 0.5 mol·L^(-1)H_(2)SO_(4)

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Rare Metals 2023年第5期42卷 1760-1772页

作者： Fei-Fei Huang Yi Qin Qing-Rui Wang Hiroaki Yoshida Lei Wen Hai Chang Ying Jin National Center for Materials Service Safety University of Science and Technology BeijingBeijing100083China Innovation Group of Marine Engineering Materials and Corrosion Control Southern Marine Science and Engineering Guangdong LaboratoryZhuhai519080China department of physical Science Hiroshima UniversityHigashi-Hiroshima739-8526Japan

The oxide film formed on TA15 alloy in0.5 mol·L^(-1)H_(2)SO_(4)at different applied potentials is investigated by evaluating the film formation current density,film thickness,surface film composition,valence state,and the electrochemical *** relative quantitative spectral analysis revealed by X-ray photoelectron spectroscopy(XPS)and X-ray absorption spectra(XAS)shows that the increasing applied potential promotes the formation of thick and high-valence state *** contrasting with XAS of the reference titanium oxides,it is found that TiO_(2)within the oxide film changes from anatase type to rutile type with the potential increases to 2.00 *** oxide film formed at passive region has better protection performance,and with the increase of applied potential,the corrosion resistance of passive film increases,whereas the ND(donor density)values obtained from the Mott-Schottky(MS)results decrease with the increasing applied potential,indicating a better uniformity and protective effect of the oxide *** on above facts,the model of the oxide films formed on TA15 at different applied potentials in passive region and dissolve region is ***,the existence forms of all the TA15alloying elements under the most corrosion resistant condition are confirmed.

关键词： TA15 Electrochemical passivation Corrosion behavior Surface compositions and structures

PREDICTION OF THE GRAIN SIZE OF SUSPENDED SEDIMENT:IMPLICATIONS FOR CALCULATING SUSPENDED SEDIMENT CONCENTRATIONS USING SINGLE FREQUENCY ACOUSTIC BACKSCATTER

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International Journal of Sediment Research 2007年第1期22卷 1-15页

作者： R. A. KUHNLE D. G. WREN J. P. CHAMBERS Dr.Research Hydraulic Engineer National Sedimentation Laboratory U. S. Department of Agriculture Agricultural Research Service Oxford Mississippi 38655 USA Senior Research Scientist National Center for Physical Acoustics University of Mississippi University Mississippi 38677 USA

Collection of samples of suspended sediment transported by streams and rivers is difficult and expensive. Emerging technologies, such as acoustic backscatter, have promise to decrease costs and allow more thorough sampling of transported sediment in streams and rivers. Acoustic backscatter information may be used to calculate the concentration of suspended sand-sized sediment given the vertical distribution of sediment size. Therefore, procedures to accurately compute suspended sediment size distributions from easily obtained river data are badly needed. In this study, techniques to predict the size of suspended sand are examined and their application to measuring concentrations using acoustic backscatter data are explored. Three methods to predict the size of sediment in suspension using bed sediment, flow criteria, and a modified form of the Rouse equation yielded mean suspended sediment sizes that differed from means of measured data by 7 to 50 percent. When one sample near the bed was used as a reference, mean error was reduced to about 5 percent. These errors in size determination translate into errors of 7 to 156 percent in the prediction of sediment concentration using backscatter data from 1 MHz single frequency acoustics.

关键词： Suspended sediment Grain size Acoustic backscatter Concentration errors

A New Experimental Method for Investigations on Microstructure of Liquid-Vapor Interface

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Chinese Journal of Chemical Physics 2021年第1期34卷 43-50,I0011页

作者： Ziyuan Li Ziwei Chen Jie Hu Hao Li Shan Xi Tian Hefei National Laboratory for physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China department of Physics Anhui Normal UniversityWuhu 241002China

Many physical,chemical,and biological processes happen in liquid-vapor interface and are profoundly influenced with the local *** contrast to the liquid bulk,molecular orientation is the remarkable one of asymmetric structural features of the *** we report an experimental method,namely,electron-impact time-delayed mass spectrometry and give a Ion Detector Time-of-Flight Tub*Liquid Microjet Ion Attrac Liq Electron Multiplier Quadrupole Mass Filter Bender j id Beai Electrons Liquid Dump Pulsed Electron Gun brief review about our recent *** brand-new method not only enables us to have more insights into the interfacial structures,as done with small-angle X-ray and neutron scatterings and vibrational sum frequency generation spectroscopy,but also provides opportunity to explore the electron-driven chemical reactions therein.

关键词： Time-delayed mass spectrometry Liquid-vapor Interface Microstructure

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一些流体力学问题的解析与数值研究

天文学报 2014年第2期55卷 189-190页

作者：孔大力 department of Mathematics College of EngineeringMathematics and Physical SciencesUniversity of Exeter

本论文5章内容分为流体静力学、黏性流体运动学和低黏性流体动力学3个部分．按研究课题划分，主要包含行星流体、生物流体与高性能计算方法3个方面．在流体静力学部分中，经典马克劳林椭球形状理论首次被推广到更真实的类地行星分层模... 详细信息

本论文5章内容分为流体静力学、黏性流体运动学和低黏性流体动力学3个部分．按研究课题划分，主要包含行星流体、生物流体与高性能计算方法3个方面．在流体静力学部分中，经典马克劳林椭球形状理论首次被推广到更真实的类地行星分层模型．该模型可准确计算在自引力平衡条件下，旋转岩石行星外表面与核．幔一边界的椭球形状．为相关行星外部引力场问题的研究和快速旋转液态内核区域内的磁流体力学数值模拟提供了关键拓扑约束．在初步将木星内部近似为不可压缩流体的情况下，形状理论也被应用到木星深部大气带状环流问题的研究中．论文中第1次给出了大气深部带状环流对木星形状和外部引力场的扰动上限．与以往基于慢转动假设的近似方法显著不同，木星快速均匀自转造成的显著扁率被严格计算．黏性流动广泛存在于微生物游泳等小尺度低速流体运动问题中．一般的球菌与杆菌可以用不同的长椭球近似表示它们的几何形状．这些细菌游动时与周围液体的准稳态相互作用可以被不可压缩黏性流动的斯托克斯方程描述．本论文第1次给出了长椭球区域外部任意平动、任意转动条件下斯托克斯方程的完整全3维解析解．应用到趋磁细菌的研究中，该理论预测的J＇b：DN磁场中的细菌运动轨迹精确地符合实验室条件下的观测结果．

关键词：磁流体力学解析解数值研究不可压缩流体斯托克斯方程几何形状流体静力学黏性流体

氮掺杂Ti_(3)C_(2)T_(x)MXene纳米片包覆的SiO_(x)实现储锂性能提升

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Science China Materials 2023年第1期66卷 51-60页

作者：张开元赵丹钱钊顾鑫杨剑钱逸泰 Key Laboratory of Colloid and Interface chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationSchool of Materials Science and EngineeringShandong UniversityJinan 250061China College of New Energy State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(East China)Qingdao 266580China Hefei National Laboratory for physical Science at Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

构建具有快速反应动力学和优异循环稳定性的SiO_(x)基负极材料是获取高性能锂离子电池的关键和挑战.本文中,我们利用三聚氰胺辅助的球磨和退火方法,合成了氮掺杂的Ti_(3)C_(2)T_(x)MXene超薄片层(NTS)包覆的SiO_(x)复合材料.通过对比实... 详细信息

构建具有快速反应动力学和优异循环稳定性的SiO_(x)基负极材料是获取高性能锂离子电池的关键和挑战.本文中,我们利用三聚氰胺辅助的球磨和退火方法,合成了氮掺杂的Ti_(3)C_(2)T_(x)MXene超薄片层(NTS)包覆的SiO_(x)复合材料.通过对比实验和理论计算,我们论证了三聚氰胺剥离MXene的作用机理.SiO_(x)与NTS之间强烈的界面相互作用(Si-O-Ti键)可以有效地增强电子转移,确保电极的稳定性.此外,具有丰富表面基团的NTS使复合材料具有赝电容性能,有利于快速储锂.因此,该复合材料展现出了长循环寿命(在1.0 A g^(-1)的电流密度下,循环800次后比容量保持为~700 mA h g^(-1))和优越的倍率性能(在5 A g^(-1)的电流密度下,比容量为596.4 mA h g^(-1)).更重要的是,在高负载量下,该复合材料在半电池和全电池中均表现出较高的面积比容量和良好的循环稳定性,展现出了良好的应用潜力.

关键词：锂离子电池长循环寿命负极材料储锂性能半电池循环稳定性界面相互作用表面基团