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The QCD Ground State Chiral Tetrahedron Symmetry
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作者 Rami Rom 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1161-1180,共20页
We propose that the exotic meson tetraquark u<sub>d</sub>~</sup>d&utilde;introduced in previous papers, may be a pseudo-Goldstone boson having a tetrahedron geometry and symmetry. The transition ... We propose that the exotic meson tetraquark u<sub>d</sub>~</sup>d&utilde;introduced in previous papers, may be a pseudo-Goldstone boson having a tetrahedron geometry and symmetry. The transition from the neutral pion superposition of two free mesons, d<sub>d</sub>~</sup> and u&utilde;, to the tetrahedron geometry with optional two chiral states may be the symmetry breaking of the QCD ground state. The u<sub>d</sub>~</sup>d&utilde;tetrahedron mass may be calculated by measuring the β decay rate variability. We assume that electrons and positrons are composite particle exotic tetraquarks, d&utilde;d<sub>d</sub>~</sup> for the electrons and u<sub>d</sub>~</sup>d<sub>d</sub>~</sup> for the positrons and confined by the strong force. We propose that the QCD tetrahedrons play a central role in electron pairing mechanism in both chemical bond forming and superconductor Cooper pairs. We propose a hypothesis where the QCD ground state tetrahedrons play a central role in low energy physics where quark exchange reactions between particles and the QCD tetrahedrons via gluon junctions transfer all the forces. The QCD ground state u<sub>d</sub>~</sup>d&utilde;tetrahedrons hypothesis provides a symmetry breaking and a mass gap may be created by the ground state QCD tetrahedrons Bose-Einstein condensate. 展开更多
关键词 QCD Vacuum Pseudo-Goldstone Boson Bose Einstein Condensate (BEC) Lattice QCD Gluon Junctions tetrahedrons Cooper Pairs Isotope Effect Superconductor Dirac Equation Klein Paradox Cosmic Web Voids Doppler Redshift Black Hole Laser
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The Optical Resolution of Chiral Tetrahedrone-type Clusters Contai- ning SCoFeM (M=Mo or W) Using High Performance Liquid Chromatography Chiral Stationary Phase 被引量:2
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作者 Xiao Qian HAN Yong Min LI +2 位作者 Yu Hua ZHANG Sheng Xiang JIANG Li Ren CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第12期1193-1194,共2页
Amylose tris (phenylcarbamate) chiral stationary phase (ATPC-CSP) was prepared and used for optical resolution of clusters 1 and 2. n-Hexane/2-propanol ( 99/1; v/v) were found to be the most suitable mobile phase on ... Amylose tris (phenylcarbamate) chiral stationary phase (ATPC-CSP) was prepared and used for optical resolution of clusters 1 and 2. n-Hexane/2-propanol ( 99/1; v/v) were found to be the most suitable mobile phase on ATPC-CSP. 展开更多
关键词 Optical resolution amylose tris (phenylcarbamate) chiral stationary phase chiral tetrahedrone type cluster.
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Locomotion Optimization and Manipulation Planning of a Tetrahedron-Based Mobile Mechanism with Binary Control 被引量:2
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作者 Ran Liu Yan-An Yao +1 位作者 Wan Ding Xiao-Ping Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第1期78-99,共22页
Locomotion and manipulation optimization is essential for the performance of tetrahedron-based mobile mechanism. Most of current optimization methods are constrained to the continuous actuated system with limited degr... Locomotion and manipulation optimization is essential for the performance of tetrahedron-based mobile mechanism. Most of current optimization methods are constrained to the continuous actuated system with limited degree of freedom(DOF), which is infeasible to the optimization of binary control multi-DOF system. A novel optimization method using for the locomotion and manipulation of an 18 DOFs tetrahedron-based mechanism called 5-TET is proposed. The optimization objective is to realize the required locomotion by executing the least number of struts.Binary control strategy is adopted, and forward kinematic and tipping dynamic analyses are performed, respectively.Based on a developed genetic algorithm(GA), the optimal number of alternative struts between two adjacent steps is obtained as 5. Finally, a potential manipulation function is proposed, and the energy consumption comparison between optimal 5-TET and the traditional wheeled robot is carried out. The presented locomotion optimization and manipulation planning enrich the research of tetrahedron-based mechanisms and provide the instruction to the successive locomotion and operation planning of multi-DOF mechanisms. 展开更多
关键词 tetrahedron-based mobile mechanism Binary control GA Locomotion optimization Manipulation planning
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Numerical Experiment for Dipole-Dipole Interaction in Electro-Magnetism with Help of a Regular Tetrahedron
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作者 Panagis G. Papadopoulos Panos D. Kiousis Christos G. Karayannis 《Open Journal of Physical Chemistry》 2019年第1期13-32,共20页
Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuousl... Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuously distributed in space. In a region, where the Electric Field is constant, in direction and magnitude, all the small Dipoles are parallel to the Electric Field, and are represented by a single, long, parallel to them, fixed in space, Electric Dipole, which is here called Compass. An Alternating current, in a straight Conductor, is studied, by a simple, short computer program, for step-by-step nonlinear dynamic analysis. It is found that, only an Alternating current, not a direct current, can produce an Electric Dipole, in a straight Conductor. The two above Dipoles (Compass-Conductor) are assumed with equal lengths &#8467;, lying on two skew lines, perpendicular to each other, at a distance &#8467;√2, thus forming, by their four ends, a Regular Tetrahedron, with side length &#8467;. Repulsion, between Like Charges, obeys the simple Coulomb Electro-Static law. Whereas Interaction (Attraction or Repulsion), between Unlike Charges, obeys a more accurate Lennard-Jones law. The analysis of Dipole-Dipole (Compass-Conductor) Interaction is performed by hand calculator. The only out-of-balance forces, in the regular Tetrahedron, acting on the Rigid Conductor, are the so-called magnetic forces. Their direction is found, in a simple Rational way, with help of Regular Tetrahedron, without recoursing to a “right-hand-rule”. The proposed model is applied to 1) The force acting on an Electric Charge moving in a magnetic field. 2) The force acting on a Current carrying straight Conductor, due to a magnetic field. 3) The magnetic fields created around a Current carrying straight Conductor. In these applications, proposed model gives reasonable results. Particularly, in third application, results, obtained by proposed model, are found in satisfactory approximation with corresponding ones, obtained by an empirical formula, based on relevant Experimental observations of H.-C. Oersted and A.-M. Ampère. So, the reliability of proposed model is checked. Position and direction of magnetic field vector coincide with those of a corresponding fixed Compass of a constant Electric Field. Main point of present work is that, without introducing the concept of a magnetic field vector, by combining field of dipoles, produced by an electric field, with dipole of an alternating current carrying conductor, the magnetic forces can be determined. 展开更多
关键词 ELECTRIC Field ELECTRIC DIPOLE Compass Conductor Alternating Current Step-by-Step Nonlinear Dynamic Algorithm Dipole-Dipole Interaction REGULAR tetrahedron Coulomb Electro-Static LAW Lennard-Jones LAW MAGNETIC Field Vector MAGNETIC Forces Oersted-Ampère Rule
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浅谈塑料离合踏板臂使用Tetrahedron有限元网格的后处理
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作者 谢文辉 《现代盐化工》 2019年第3期59-61,共3页
汽车轻量化为节能减排作出了巨大贡献,而“以塑代钢”是轻量化中很常用的途径。有限元分析作为“以塑代钢”中一个非常重要的评估工具,约束其分析准确性的因素除了材料参数的定义、有限元分析模型的建立之外,还有有限单元网格的选择。... 汽车轻量化为节能减排作出了巨大贡献,而“以塑代钢”是轻量化中很常用的途径。有限元分析作为“以塑代钢”中一个非常重要的评估工具,约束其分析准确性的因素除了材料参数的定义、有限元分析模型的建立之外,还有有限单元网格的选择。对于壁厚不均匀的塑料离合踏板臂,使用Tetrahedron网格类型进行有限元分析,后处理时最大节点应力以及此网格单元的最大积分点应力也会有差异。结果显示,网格密度、积分点数量的变化对积分点应力的变化相对更小。 展开更多
关键词 塑料离合踏板臂 tetrahedron网格 节点应力 积分点应力
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Multipartite Entanglement of a Tetrahedron Lattice 被引量:2
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作者 ZHANG Rong ZHU Shi-Qun HAO Xiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期863-872,共10页
关键词 多成分纠缠态 合作 三维 四面体晶格
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A New Kind of Conjugate-nested Central Configurations in Consisted of One Regular Tetrahedron and One Regular Octahedron 被引量:1
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作者 LIU Xue-fei XIANG Yi-hua 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期309-316,共8页
在 R3 的一种新盒子配置,结合巢由一个常规四面体和一常规八面体组成了是配置是的 discussed.If 一种中央配置,当时,外面的层的所有群众是相等的,里面的群众层也是 equivalent.At 一样的时间在 p 之间的下列关系( r=3/3 是尺寸的半... 在 R3 的一种新盒子配置,结合巢由一个常规四面体和一常规八面体组成了是配置是的 discussed.If 一种中央配置,当时,外面的层的所有群众是相等的,里面的群众层也是 equivalent.At 一样的时间在 p 之间的下列关系( r=3/3 是尺寸的半径比率)并且集体比率 r=m/m 一定是满足的r=-m/m=( +3 )( 3+2+2 )为任何妈的 -3/2+(-+3)(3-2+2)-3/2-4.2-3/2-2-4-1-2/2(1+)(3+2+2)-3/2+2(-1)(3-2+2)-3/2-4(22)-3。 展开更多
关键词 一类 正四面体 正八面体 共轭套中心构型
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Eight-body central configuration for conjugate-nested regular tetrahedrons
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作者 刘学飞 《Journal of Chongqing University》 CAS 2007年第4期294-298,共5页
The sufficient and necessary conditions, the existence and uniqueness of a new class of central configuration in R3, for the conjugate-nest consisting of two regular tetrahedrons, are proved. If the configuration is a... The sufficient and necessary conditions, the existence and uniqueness of a new class of central configuration in R3, for the conjugate-nest consisting of two regular tetrahedrons, are proved. If the configuration is a central configuration, then all masses of outside layer are equivalent, and the masses of inside layer are also equivalent. At the same time ρ (the ratio of the sizes) and mass ratio τ=m/?m must be satisfied by some formulas. For any radius ratios ρ∈(0, 0.152 996 918 2) or (0.715 223 148 7, 1.398 165 037), there is only one central configuration. Otherwise, for any given mass ratio τ , there may exist more than one central configuration. 展开更多
关键词 数学理论 计算方法 结构特征 四面体
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DNA tetrahedron-based split aptamer probes for reliable imaging of ATP in living cells
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作者 Lie Li Jie Wang +5 位作者 Huishan Jiang Xiaohong Wen Mei Yang Suping Li Qiuping Guo Kemin Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第3期153-156,共4页
Accurate detection and imaging of adenosine triphosphate(ATP)expression levels in living cells is of great value for understanding cell metabolism,physiological activities,and pathologic mechanisms.Here,we developed a... Accurate detection and imaging of adenosine triphosphate(ATP)expression levels in living cells is of great value for understanding cell metabolism,physiological activities,and pathologic mechanisms.Here,we developed a DNA tetrahedron-based split aptamer probe(TD probe)for ratiometric fluorescence imaging of ATP in living cells.The TD probe is constructed by hybridizing two split ATP aptamer probes(Apt-a and Apt-b)to a DNA tetrahedron assembled by four DNA oligonucleotides(T1,T2,T3 and T4).In the presence of ATP,the TD probe will alter its structure from the open to closed state,thus bringing the separated donor and acceptor fluorophores into close proximity for high fluorescence resonance energy transfer(FRET)signals.The TD probe exhibits low cytotoxicity,efficient cell internalization and good biological stability.Moreover,based on the FRET“off”to“on”signal output mode,the TD probe can effectively avoid false-positive signals from complex biological matrices,which is significant for long-term reliable imaging in living cells.In addition,by changing the split aptamers attached to DNA tetrahedron,the proposed strategy may be extended for detecting various intracellular targets.Collectively,this strategy provides a valuable sensing platform for biomarkers analysis in living cells,thus having great potential for early clinical diagnosis and therapeutic evaluation. 展开更多
关键词 Adenosine triphosphate DNA tetrahedron Split aptamer Fluorescence resonance energy transfer Living cell imaging
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考虑自由液面影响的多凸体结构浮态计算方法
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作者 刘虓 周全 +1 位作者 樊天慧 陈超核 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第5期62-70,共9页
针对液舱内自由液面对浮态和稳性的影响,文中提出了一种新的多凸体组合结构浮态算法。该方法将浮体和液舱分解成多个四面体单元,通过分析每个四面体与水面/液面的相对位置关系来确定浮体的浮力和浮心以及液舱液体的重心。该方法还提出... 针对液舱内自由液面对浮态和稳性的影响,文中提出了一种新的多凸体组合结构浮态算法。该方法将浮体和液舱分解成多个四面体单元,通过分析每个四面体与水面/液面的相对位置关系来确定浮体的浮力和浮心以及液舱液体的重心。该方法还提出了一种改进的双重迭代法用来确定多凸体组合结构的浮态:内层迭代法模拟浮体的升沉运动,得到浮体外的水面方程和液舱内的液面方程;通过外层迭代法模拟浮体的旋转运动。两种迭代方法交替进行,直至浮体的重力作用线和浮力作用线之间的距离满足精度要求,同时重力等于浮力。自编程序对某半潜船和某半潜式海洋平台的多种典型工况进行了浮态计算,同时也考虑了自由液面影响。此外利用Maxsurf建模进行了对比分析,还利用AUTOCAD进行了精度验证。对照结果表明:该研究提出的算法可以考虑自由液面对浮态的影响,原理清晰,收敛性好;算法无论对传统的单凸体结构(例如单体船),还是多凸体结构(例如多体船、漂浮式海洋平台等)均更容易取得准确解,且计算效率更高;算法可以实现“搭积木”式的建模方式,多工况建模时可以极大地减小工作量;算法无需依赖国外第三方图形平台(比如AUTOCAD、CATIA),可为我国相关工业软件的国产化打下良好的基础。 展开更多
关键词 自由液面 浮态 四面体 双重迭代
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中国舞蹈艺术的审美文化观——内外部相融的舞蹈研究方法论探讨
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作者 慕羽 《南京艺术学院学报(音乐与表演版)》 北大核心 2024年第1期146-161,I0005,共17页
舞蹈创作和批评研究既包括“生命体”身体意识和时空关系的内部规律探讨,也要阐释舞蹈与人类其他社会实践的外部规律联系,内外部结合的方法论很有意义。舞蹈分析与动作分析并非相同概念。舞蹈创作和研究从业者除了提升动作分析理论,还... 舞蹈创作和批评研究既包括“生命体”身体意识和时空关系的内部规律探讨,也要阐释舞蹈与人类其他社会实践的外部规律联系,内外部结合的方法论很有意义。舞蹈分析与动作分析并非相同概念。舞蹈创作和研究从业者除了提升动作分析理论,还应密切关注新的编舞走向和跨学科的舞蹈研究趋势。20世纪八九十年代以来,西方舞蹈学者的舞蹈分析框架,融入了文化研究,揭示出仅作动作分析或内部研究的局限性;中国舞蹈学者的元素分析、形态分析也与舞蹈文化密切相关。在全球在地化和全媒体时代,作为一种方法论,舞蹈艺术的“审美文化观”将舞蹈创作到批评视为审美文化活动,承袭了古今中西文化汇通的中国美学、文学、理论界和舞蹈学的相关研究,自律论、他律论与通律论相辅相成,重视具体的真实的人本体,一方面强调侧重内部研究的“跨媒介性”视角,另一方面也倡导将内外部打通的“跨文化”观,尝试既在审美中看舞蹈文化,也在文化中看舞蹈审美,是一种具有“中国式现代化”路径的文艺观和方法论。“点线面体”充分融合的审美文化四面体图式,基于艾布拉姆斯“四要素”三角和格里斯沃尔德“文化菱形”理论基础,融入拉班动作分析四面体思路,并与中国人文社科学术界倡导多年的“审美文化”研究相通。 展开更多
关键词 中国舞蹈创作 中国舞蹈批评 方法论 审美文化 四要素 四面体
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Efficient renal clearance of DNA tetrahedron nanopartides enables quantitative evaluation of kidney function 被引量:2
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作者 Dawei Jiang Hyung-Jun lm +7 位作者 Madeline E. Boleyn Christopher G. England Dalong Ni Lei Kang Jonathan W. Engle Peng Huang Xiaoli Lan Weibo Cai 《Nano Research》 SCIE EI CAS CSCD 2019年第3期637-642,共6页
DNA tetrahedro n nano structure (DTN) is one of the simplest DNA nano structures and has bee n successfully applied for biose nsin g, imagi ng, and treatment of can cer. To facilitate its biomedical applications and p... DNA tetrahedro n nano structure (DTN) is one of the simplest DNA nano structures and has bee n successfully applied for biose nsin g, imagi ng, and treatment of can cer. To facilitate its biomedical applications and pote ntial clinical tran slation, fun dame ntal un derstandi ng of DTN's transportation among major organs in living organisms becomes increasingly important. Here, we describe the efficient renal clearanee of DTN in healthy mice by using positron emission tomography (PET) imaging. The kidney elimination of DTN was later applied for renal function evaluation in murine models of unilateral ureteral obstruction (UUO). We further established a mathematical program of DTN to validate its changes of transportation pattern in healthy and UUO mice. We believe the establishment of pharmacokinetic profiles and mathematical model of DTN may provide in sight for future optimization of DNA nano structures for biomedical applications. 展开更多
关键词 POSITRON emission tomography (PET) imaging DNA NANOTECHNOLOGY DNA tetrahedron nanoparticle RENAL clearanee kidney DYSFUNCTION
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Solid rocket motor propellant grain burnback simulation based on fast minimum distance function calculation and improved marching tetrahedron method 被引量:2
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作者 Pengfei REN Hongbo WANG +4 位作者 Guofeng ZHOU Jiani LI Qiang CAI Jiaquan YU Ya YUAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第4期208-224,共17页
To efficiently compute arbitrary propellant grain evolution of the burning surface with uniform and non-uniform burning rate for solid rocket motor,a unified framework of burning surface regression simulation has been... To efficiently compute arbitrary propellant grain evolution of the burning surface with uniform and non-uniform burning rate for solid rocket motor,a unified framework of burning surface regression simulation has been developed based on minimum distance function.In order to speed up the computation of the mini-mum distance between grid nodes of grain and the triangular mesh of burning surface,a fast distance querying method based on the equal size cube voxel structure was employed.An improved marching tetrahedron method based on piecewise linear approximation was carried out on second-order tetrahedral elements,achieved high-efficiency and adequate accuracy of burning surface extraction simultaneously.The cases of star grain,finocyl grain,and non-uniform tube grain were studied to verify the proposed method.The observed result indicates that the grain burnback computation method could realize the accurate simulation on unstructured tetrahedral mesh with a desirable performance on computational time. 展开更多
关键词 Burning surface area Finocyl grain Level set Marching tetrahedron Minimum distance function Solid propellants Solid rocket motor
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3D Numerical Simulation of Non-isothermal Resin Transfer Molding Filling Process Using Unstructured Tetrahedron Mesh 被引量:1
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作者 施飞 董湘怀 《Journal of Shanghai Jiaotong university(Science)》 EI 2010年第6期684-689,共6页
We present a numerical formulation for resin flow based on the concept of quasi-steady state situation at the flow front. To be fit for complicated product shapes,we use the four-node unstructured tetrahedron mesh bas... We present a numerical formulation for resin flow based on the concept of quasi-steady state situation at the flow front. To be fit for complicated product shapes,we use the four-node unstructured tetrahedron mesh based on which the numerical formulation of temperature and degree of cure is developed. The validity of our method is established in the case where ffexible meshes are used. The results show that the numerical procedure,tested on known data,provides numerically valid and reasonably accurate predictions. 展开更多
关键词 3D non-isothermal resin transfer molding (RTM) numerical simulation unstructured tetrahedron mesh
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Low-coordinated surface sites make truncated Pd tetrahedrons as robust ORR electrocatalysts outperforming Pt for DMFC devices 被引量:1
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作者 Xiaoling Wang Jingwei Li +6 位作者 Xiaotong Yang Fengling Zhao Yongfei Li Daliang Zhang Li-Yong Gan Ke Xin Yao Qiang Yuan 《Nano Research》 SCIE EI CSCD 2022年第9期7951-7958,共8页
Developing highly stable and active non-Pt oxygen reduction reaction(ORR)electrocatalysts for power generation device raises great concerns and remains a challenge.Here,we report novel truncated Pd tetrahedrons(T-Pd-T... Developing highly stable and active non-Pt oxygen reduction reaction(ORR)electrocatalysts for power generation device raises great concerns and remains a challenge.Here,we report novel truncated Pd tetrahedrons(T-Pd-Ths)enclosed by{111}facets with excellent uniformity,which have both low-coordinated surface sites and distinct lattice distortions that would induce“local strain”.In alkaline electrolyte,the T-Pd-Ths/C achieves remarkable ORR specific/mass activity(SA/MA)of 2.46 mA·cm^(−2)/1.69 A·mgPd^(−1),which is 12.3/16.9 and 10.7/14.1 times higher than commercial Pd/C and Pt/C,respectively.The T-Pd-Ths/C also exhibits high in-situ carbon monoxide(CO)tolerance and 50,000 cycles durability with an activity loss of 7.69%and morphological stability.The rotating ring-disk electrode(RRDE)measurements show that a 4-electron process occurs on T-PdThs/C.Theoretical calculations demonstrate that the low-coordinated surface sites contribute largely to the enhancement of ORR activity.In actual direct methanol fuel cell(DMFC)device,the T-Pd-Ths/C delivers superior open-circuit voltage(OCV)and peak power density(PPD)to commercial Pt/C from 25 to 80℃,and the maximum PPD can reach up to 163.7 mW·cm−2.This study demonstrates that the T-Pd-Ths/C holds promise as alternatives to Pt for ORR in DMFC device. 展开更多
关键词 Pd tetrahedrons low-coordinated sites lattice distortion oxygen reduction reaction direct methanol fuel cells
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Electronic transport through tetrahedron-structured DNA-like system 被引量:2
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作者 Wei Zhu Ai-Min Guo Qing-Feng Sun 《Frontiers of physics》 SCIE CSCD 2014年第6期774-779,共6页
我们理论上调查一个多终端的电子运输性质在一个一致磁场下面的组织四面体的 DNA。基于一个紧密绑定的模型,水流和非局部的电阻被采用 Landauer-B
关键词 电子输运性质 四面体结构 系统 均匀磁场 傅立叶变换 DNA 局部阻力 分子开关
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Hypercube and Tetrahedron Algebra
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作者 Bo HOU Suogang GAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第2期293-306,共14页
Let D be an integer at least 3 and let H(D, 2) denote the hypercube. It is known that H(D, 2) is a Q-polynomial distance-regular graph with diameter D, and its eigenvalue sequence and its dual eigenvalue sequence are ... Let D be an integer at least 3 and let H(D, 2) denote the hypercube. It is known that H(D, 2) is a Q-polynomial distance-regular graph with diameter D, and its eigenvalue sequence and its dual eigenvalue sequence are all {D-2i}D i=0. Suppose that denotes the tetrahedron algebra. In this paper, the authors display an action of ■ on the standard module V of H(D, 2). To describe this action, the authors define six matrices in Mat X(C), called A, A*, B, B*, K, K*.Moreover, for each matrix above, the authors compute the transpose and then compute the transpose of each generator of ■ on V. 展开更多
关键词 超立方体 四面体 代数 特征值序列 距离正则图 标准模块 多项式 发电机
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B-splines on 3-D tetrahedron partition in four-directional mesh
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作者 孙家昶 施锡泉 《Science China Mathematics》 SCIE 2001年第4期491-496,共6页
It is more difficult to construct 3-D splines than in 2-D case. Some results in the three directional meshes of bivariate case have been e xtended to 3-D case and corresponding tetrahedron partition has been construct... It is more difficult to construct 3-D splines than in 2-D case. Some results in the three directional meshes of bivariate case have been e xtended to 3-D case and corresponding tetrahedron partition has been constructed. The support of related Bsplines and their recurrent formulas on integration and differentiationdifference are obtained. The results of this paper can be extended into higher dimension spaces, and can be also used in wavelet analysis, because of the relationship between spline and wavelets. 展开更多
关键词 高维的花键 关花键 四面体分区
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基于移动平台的三维风速风向动态测量系统
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作者 崔永俊 杨阳阳 侯钰龙 《电子器件》 CAS 北大核心 2023年第2期437-442,共6页
由于风速风向对帆船等移动平台的影响,需要实现对风速风向的动态测量,因此设计了一款基于时差法的正四面体非正交结构超声波阵列的动态测量系统。该系统通过测量超声波在顺风和逆风下传播的速度不同,结合测量装置的结构解析,得到风速风... 由于风速风向对帆船等移动平台的影响,需要实现对风速风向的动态测量,因此设计了一款基于时差法的正四面体非正交结构超声波阵列的动态测量系统。该系统通过测量超声波在顺风和逆风下传播的速度不同,结合测量装置的结构解析,得到风速风向和俯仰角,利用磁力计补偿方位信息数据和中值滤波算法,解决了在移动平台上实时动态采集风速风向和俯仰角的问题。经实际测试,系统风速测量误差在±1 m/s以内,风向测量偏差不超过0.8°,俯仰角测量偏差不超过1°,达到预期设计要求。 展开更多
关键词 风速风向动态测量 正四面体非正交结构 方位信息补偿 时差法 中值滤波算法
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四面体十二点球定理推广研究的进展
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作者 曾建国 《赣南师范大学学报》 2023年第6期1-6,共6页
回顾了人们对四面体十二点球定理的推广研究历程,对历年来所得的主要研究结果进行了简介.在此基础上对有关结论作进一步推广研究,得到关于四面体的32点共球定理.
关键词 四面体 十二点球定理 K号心 k+1号球面 32点共球定理
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