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Monte Carlo simulation of asymmetrical growth of cube-shaped nanoparticles
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作者 王元元 谢华清 +1 位作者 吴子华 邢姣娇 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期437-445,共9页
We simulated the asymmetrical growth of cube-shaped nanoparticles by applying the Monte Carlo method.The influence of the specific mechanisms on the crystal growth of nanoparticles has been phenomenologically describe... We simulated the asymmetrical growth of cube-shaped nanoparticles by applying the Monte Carlo method.The influence of the specific mechanisms on the crystal growth of nanoparticles has been phenomenologically described by efficient growth possibilities along different directions(or crystal faces).The roles of the thermodynamic and kinetic factors have been evaluated in three phenomenological models.The simulation results would benefit the understanding about the cause and manner of the asymmetrical growth of nanoparticles. 展开更多
关键词 cube-shaped nanoparticles asymmetrical growth Monte Carlo simulation
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Progresses and Prospects of Asymmetrically Coordinated Single Atom Catalysts for Lithium-Sulfur Batteries
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作者 Rong Zhou Shaonan Gu +2 位作者 Meng Guo Shuzheng Xu Guowei Zhou 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期48-63,共16页
Lithium-sulfur batteries(LSBs)are widely regarded as promising next-generation batteries due to their high theoretical specific capacity and low material cost.However,the practical applications of LSBs are limited by ... Lithium-sulfur batteries(LSBs)are widely regarded as promising next-generation batteries due to their high theoretical specific capacity and low material cost.However,the practical applications of LSBs are limited by the shuttle effect of lithium polysulfides(LiPSs),electronic insulation of charge and discharge products,and slow LiPSs conversion reaction kinetics.Accordingly,the introduction of catalysts into LSBs is one of the effective strategy to solve the issues of the sluggished LiPS conversion.Because of their nearly 100%atom utilization and high electrocatalytic activity,single-atom catalysts(SACs)have been widely used as reaction mediators for LSBs’reactions.Excitingly,the SACs with asymmetric coordination structures have exhibited intriguing electronic structures and superior catalytic activities when compared to the traditional M-N_(4)active sites.In this review,we systematically describe the recent advancements in the installation of asymmetrically coordinated single-atom structure as reactions catalysts in LSBs,including asymmetrically nitrogen coordinated SACs,heteroatom coordinated SACs,support effective asymmetrically coordinated SACs,and bimetallic coordinated SACs.Particularly noteworthy is the discussion of the catalytic conversion mechanism of LiPSs spanning asymmetrically coordinated SACs.Finally,a perspective on the future developments of asymmetrically coordinated SACs in LSB applications is provided. 展开更多
关键词 asymmetrical coordination conversion catalysis Li-S batteries shuttle effect single atom catalysts
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Bose–Einstein distribution temperature features of quasiparticles around magnetopolaron in Gaussian quantum wells of alkali halogen ions
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作者 Xin Zhang Sarengaowa +7 位作者 Shuang Han Ran An Xin-Xue Zhang Xin-Ying Ji Hong-Xu Jiang Xin-Jun Ma Pei-Fang Li Yong Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期521-526,共6页
We have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum wells.The obtain... We have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum wells.The obtained results showed that under magnetic field effect,magnetopolaron quasiparticle was formed through the interaction of electrons and surrounding phonons.At the same time,magnetopolaron was influenced by phonon temperature statistical law and important energy level shifts down and binding energy increases.This revealed that lattice temperature and magnetic field could easily affect magnetopolaron and the above results could play key roles in exploring thermoelectric conversion and conductivity of crystal materials. 展开更多
关键词 temperature effect quantum well asymmetric Gaussian potential MAGNETOPOLARON
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Model-free Speed Control of Single-phase Flux Switching Motor with an Asymmetrical Rotor
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作者 Zongsheng Zhang Congcong Guo 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第3期255-263,共9页
This paper proposes and implements a model-free open-loop iterative learning control(ILC)strategy to realize the speed control of the single-phase flux switching motor(FSM)with an asymmetrical rotor.Base on the propos... This paper proposes and implements a model-free open-loop iterative learning control(ILC)strategy to realize the speed control of the single-phase flux switching motor(FSM)with an asymmetrical rotor.Base on the proposed winding control method,the asymmetrical rotor enables the motor to generate continuous positive torque for positive rotation,and relatively small resistance torque for negative rotation.An initial iteration coefficient and variable iteration coefficient optimized scheme was proposed based on the characteristics of the hardware circuit,thereby forming the model-free strategy.A series of prototype experiments was carried out.Experimental results verify the effectiveness and practicability of the proposed ILC strategy. 展开更多
关键词 asymmetrical rotor Model-free iterative control Prototype experiments Single-phase flux switching motor
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Numerical Exploration of Asymmetrical Impact Dynamics: Unveiling Nonlinearities in Collision Problems and Resilience of Reinforced Concrete Structures
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作者 AL-Bukhaiti Khalil Yanhui Liu +1 位作者 Shichun Zhao Daguang Han 《Structural Durability & Health Monitoring》 EI 2024年第3期223-254,共32页
This study provides a comprehensive analysis of collision and impact problems’ numerical solutions, focusing ongeometric, contact, and material nonlinearities, all essential in solving large deformation problems duri... This study provides a comprehensive analysis of collision and impact problems’ numerical solutions, focusing ongeometric, contact, and material nonlinearities, all essential in solving large deformation problems during a collision.The initial discussion revolves around the stress and strain of large deformation during a collision, followedby explanations of the fundamental finite element solution method for addressing such issues. The hourglassmode’s control methods, such as single-point reduced integration and contact-collision algorithms are detailedand implemented within the finite element framework. The paper further investigates the dynamic responseand failure modes of Reinforced Concrete (RC) members under asymmetrical impact using a 3D discrete modelin ABAQUS that treats steel bars and concrete connections as bond slips. The model’s validity was confirmedthrough comparisons with the node-sharing algorithm and system energy relations. Experimental parameterswere varied, including the rigid hammer’s mass and initial velocity, concrete strength, and longitudinal and stirrupreinforcement ratios. Findings indicated that increased hammer mass and velocity escalated RC member damage,while increased reinforcement ratios improved impact resistance. Contrarily, increased concrete strength did notsignificantly reduce lateral displacement when considering strain rate effects. The study also explores materialnonlinearity, examining different materials’ responses to collision-induced forces and stresses, demonstratedthrough an elastic rod impact case study. The paper proposes a damage criterion based on the residual axialload-bearing capacity for assessing damage under the asymmetrical impact, showing a correlation betweendamage degree hammer mass and initial velocity. The results, validated through comparison with theoreticaland analytical solutions, verify the ABAQUS program’s accuracy and reliability in analyzing impact problems,offering valuable insights into collision and impact problems’ nonlinearities and practical strategies for enhancingRC structures’ resilience under dynamic stress. 展开更多
关键词 Geometric nonlinearity contact nonlinearity material nonlinearity collision problems finite element method stress and strain damage criterion RC members asymmetrical impact
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Interfacial microstructure evolution for coordinated deformation of Mg/Al composite plates by asymmetrical rolling with differential temperature rolls
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作者 Junyi Lei Lifeng Ma +4 位作者 Zhihui Cai Weitao Jia Yuan Yuan Hucheng Pan Hongbo Xie 《Journal of Magnesium and Alloys》 CSCD 2024年第10期4244-4258,共15页
In this work,Mg/Al composite plates with different thickness ratios were prepared by the asymmetrical rolling process with differential temperature rolls and isothermal symmetrical rolling.Microstructural evolution an... In this work,Mg/Al composite plates with different thickness ratios were prepared by the asymmetrical rolling process with differential temperature rolls and isothermal symmetrical rolling.Microstructural evolution and mechanical properties of matrix and composite materials with different thicknesses were analyzed.Influence of thickness ratios on the coordinated deformability of heterogeneous metals and interface toughness under the action of temperature gradient and shear force was investigated.Results show that the relative deformation rates of matrix and composite materials converge gradually under the influence of work hardening of Mg/Al layer.The Mg layer is mainly DRXed grains and texture intensity gradually weakens with increasing thickness ratio.The Al layer is mostly dominated by subgrains and deformed grains,which have a strong correlation with thickness ratio.Strength and plasticity of composites first increase and then decrease with increasing thickness ratio.Fracture of composite plate occurs in intermetallic compounds(IMCs).Thickness of IMCs has a strong positive correlation with thickness ratio.When the thickness ratio of AZ31B/Al6061 for 5,the relative thickness of IMCs is the largest and the relative bonding strength is the smallest.When the thickness ratio of AZ31B/Al6061 for 3,there is no element aggregation in IMCs,and the comprehensive mechanical properties of composite plate are comparatively better. 展开更多
关键词 Composite plate Thickness ratio asymmetrical rolling Microstructure Fracture behavior
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Comparative Study of the Reliability and Complexity of Symmetrical and Asymmetrical Cryptosystems for the Protection of Academic Data in the Democratic Republic of Congo
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作者 Mugaruka Buduge Gulain Jeremie Ndikumagenge +2 位作者 Buhendwa Nyenyezi Justin Bulonza Masumbuko Alexis Katho Seba Jacques 《Journal of Information Security》 2024年第3期299-307,共9页
In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any mod... In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any modern company. A companys operational and historical data contains strategic and operational knowledge of ever-increasing added value. The emergence of a new paradigm: big data. Today, the value of the data scattered throughout this mother of knowledge is calculated in billions of dollars, depending on its size, scope and area of intervention. With the rise of computer networks and distributed systems, the threats to these sensitive resources have steadily increased, jeopardizing the existence of the company itself by drying up production and losing the interest of customers and suppliers. These threats range from sabotage to bankruptcy. For several decades now, most companies have been using encryption algorithms to protect and secure their information systems against the threats and dangers posed by the inherent vulnerabilities of their infrastructure and the current economic climate. This vulnerability requires companies to make the right choice of algorithms to implement in their management systems. For this reason, the present work aims to carry out a comparative study of the reliability and effectiveness of symmetrical and asymmetrical cryptosystems, in order to identify one or more suitable for securing academic data in the DRC. The analysis of the robustness of commonly used symmetric and asymmetric cryptosystems will be the subject of simulations in this article. 展开更多
关键词 Comparative Study CRYPTOSYSTEMS Symmetric Encryption Asymmetric Encryption
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Formation mechanism and organizational controlling of ultra-fine-grain copper processed by asymmetrical accumulative rolling-bond and annealing 被引量:2
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作者 王军丽 徐瑞东 +2 位作者 王绍华 钱天才 史庆南 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2672-2678,共7页
The initial copper with large grain sizes of 60-100 μm was processed by six passes asymmetrical accumulative rolling-bond (AARB) and annealing, the ultra-fine-grained (UFG) copper with grain size of 200 nm was ob... The initial copper with large grain sizes of 60-100 μm was processed by six passes asymmetrical accumulative rolling-bond (AARB) and annealing, the ultra-fine-grained (UFG) copper with grain size of 200 nm was obtained, and the microstructures and properties were studied. The results show that there are large sub-structures and also texture component C for the UFG copper obtained by six passes AARB, possessing high strength and microhardness in company with poor elongation and conductivity. Thereafter, the UFG copper was annealed at 220 °C for 35 min, in which the sub-structures disappear, the grain boundaries are composed of big angle grain boundaries, and the textures are composed of a variety of texture components and parts of twins. Compared with the UFG copper obtained by six passes AARB, the tensile strength and yield strength for the UFG copper obtained by six passes AARB and annealing at 220 °C for 35 min are decreased slightly, the elongation and conductivity are improved obviously. 展开更多
关键词 ultra-fine-grain copper asymmetrical accumulative rolling-bond ANNEALING formation mechanism organizational controlling elongation conductivity
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Influence of symmetric and asymmetric rolling on texture evolution of work-hardened AA 5xxx aluminium alloy
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作者 MatjažGODEC Stefan ZAEFFERER +2 位作者 Jakob KRANER Črtomir DONIK Irena PAULIN 《中国有色金属学报》 北大核心 2025年第1期30-44,共15页
The textures and microstructures of hot-and cold-rolled sheets of an AA 5454 aluminium alloy were studied,with special attention paid to comparing the texture development for the symmetric and asymmetric cold rolling.... The textures and microstructures of hot-and cold-rolled sheets of an AA 5454 aluminium alloy were studied,with special attention paid to comparing the texture development for the symmetric and asymmetric cold rolling.Scanning electron microscopy with electron-backscatter diffraction was used to monitor the development of the microstructure in the differently deformed and additionally annealed samples.Details of the formations and transformations of individual texture components occurring during the rolling processes were observed and discussed.The average grain sizes,textures and mechanical properties were correlated and explained for the symmetric and asymmetric cold-rolled samples.The asymmetric rolling is beneficial in terms of deep drawability because it reduces the planar anisotropy of the annealed material due to the decrease of the Cube,Goss,rotated-Cube and η-fibre texture components and at the same time strengthens X1-and X2-fibre texture components which are shear texture components and improve deep drawability.During the asymmetric cold rolling,the temperature increases due to friction,triggering recrystallisation processes and leading to larger grains.It is also confirmed that asymmetric cold rolling uses less rolling force and consequently less energy to produce a final material with better formability,particularly earing. 展开更多
关键词 crystallographic texture EBSD aluminium alloy symmetric/asymmetric rolling ANISOTROPY
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Chiral inorganic nanocatalysts for electrochemical and enzyme⁃mimicked biosensing
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作者 LIU Chuang SUN Lichao ZHANG Qingfeng 《无机化学学报》 北大核心 2025年第1期59-78,共20页
In recent years,chiral inorganic nanomaterials have become promising candidates for applications in sensing,catalysis,biomedicine,and photonics.Plasmonic nanomaterials with an intrinsic chiral structure exhibit intrig... In recent years,chiral inorganic nanomaterials have become promising candidates for applications in sensing,catalysis,biomedicine,and photonics.Plasmonic nanomaterials with an intrinsic chiral structure exhibit intriguing geometry‑dependent optical chirality,which benefits the combination of plasmonic characteristics with chirality.Recent advances in the biomolecule‑directed geometric control of intrinsically chiral plasmonic nanomaterials have further provided great opportunities for their widespread applications in many emerging technological areas.In this review,we present the recent progress in biosensing using chiral inorganic nanomaterials,with a particular focus on electrochemical and enzyme‑mimicking catalytic approaches.This paper commences with a review of the basic tenets underlying chiral nanocatalysts,incorporating the chiral ligand‑induced mechanism and the architectures of intrinsically chiral nanostructures.Additionally,it methodically expounds upon the applications of chiral nanocatalysts in the realms of electrochemical biosensing and enzyme‑mimicking catalytic biosensing respectively.Conclusively,it proffers a prospective view of the hurdles and prospects that accompany the deployment of chiral nanoprobes for nascent biosensing applications.By rational design of the chiral nanoprobes,it is envisioned that biosensing with increasing sensitivity and resolution toward the single‑molecule level can be achieved,which will substantially promote sensing applications in many emerging interdisciplinary areas. 展开更多
关键词 chiral inorganic nanomaterial chiral plasmonic electrochemical biosensing enzyme‑mimicked biosensing asymmetric nanocatalysis
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Multiple Plasmonic Resonances and Cascade Effect in Asymmetrical Ag Nanowire Homotrimer
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作者 李跃 费广涛 +3 位作者 许少辉 商国亮 欧阳浩淼 张立德 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期489-496,I0002,共9页
Plasmonic Ag nanowire homotrimer with asymmetrical radii and separations, which exhibits characteristics of multiple plamonic resonances and different electric field distributions, is systematically investigated by me... Plasmonic Ag nanowire homotrimer with asymmetrical radii and separations, which exhibits characteristics of multiple plamonic resonances and different electric field distributions, is systematically investigated by means of 2D finite element method. It was found that the dark and bright modes appear in asymmetrical nanowire homotrimer. In addition, when the dark modes appear between the smaller radii of the nanowires, the cascade effect results in enhanced electric field between the smaller radii nanowires. As a result of the appearance of the bright modes between the smaller radii of the nanowires, the restriction of the cascade effect generates enhanced electric field between the bigger nanowires. 展开更多
关键词 Asymmetric homotrimer Bright and dark modes Extinction cross section Cascade effect
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Stability analyses of the mass abrasive projectile high-speed penetrating into concrete target. Part Ⅱ: Structural stability analyses 被引量:5
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作者 Hao Wu Xiao-Wei Chen +1 位作者 Qin Fang Li-Lin He 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期943-955,共13页
The initial oblique and attacking angles as well as the asymmetrical nose abrasion may lead to bending or even fracture of a projectile,and the penetration efficiency decreases distinctly.The structural stability of a... The initial oblique and attacking angles as well as the asymmetrical nose abrasion may lead to bending or even fracture of a projectile,and the penetration efficiency decreases distinctly.The structural stability of a high-speed projectile non-normally penetrating into concrete and the parametric influences involved are analyzed with the mass abrasion taken into account.By considering the symmetrical or asymmetrical nose abrasion as well as the initial oblique and attacking angles,both the axial and the transverse drag forces acting on the projectile are derived.Based on the ideal elastic-plastic yield criterion,an approach is proposed for predicting the limit striking velocity(LSV)that is the highest velocity at which no yielding failure has occurred and the projectile can still maintain its integral structural stability.Furthermore,some particular penetration scenarios are separately discussed in detail.Based on the engineering model for the mass loss and nose-blunting of ogive-nose projectiles established in Part I of this study,the above approach is validated by several high-speed penetration tests.The analysis on parametric influences indicates that the LSV is reduced with an increase in the asymmetrical nose abrasion,thelength-diameter-ratio,and the concrete strength,as well as the oblique and attacking angles.Also,the LSV raises with an increase in the initial caliber-radius-head(CRH)and the dimensionless cartridge thickness of a projectile. 展开更多
关键词 PROJECTILE High-speed penetration Concrete Oblique angle Attacking angle asymmetrical nose abrasion
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SEMI-ACTIVE CONTROL OF VEHICLE SUSPENSION WITH MAGNETO-RHEOLOGICAL DAMPERS PARTⅡ——EVALUATION OF SUSPENSION PERFORMANCE 被引量:6
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作者 WANG Enrong YING Liang +2 位作者 WANG Wanjun RAKHEJA Subhash SU Chunyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第2期45-52,共8页
The design and analysis of an intelligent vehicle suspension with MR dampers should address hybrid semi-active control goals, such as rejection of current-switching discontinuity and MR-damper hysteresis, asymmetric d... The design and analysis of an intelligent vehicle suspension with MR dampers should address hybrid semi-active control goals, such as rejection of current-switching discontinuity and MR-damper hysteresis, asymmetric damping from the symmetric MR-damper design, robustness on the vehicle operation parameter uncertainties and consideration of essential multiple suspension goals. Following the proposed skyhook-based asymmetric semi-active controller (Part I ) for achieving the above goals, herein, a set of suspension performance measures and three kinds of varying amplitude harmonic, rounded pulse and really measured random excitations are systematically defined, and the sensitivity of quarter-vehicle MR-suspension performance to variations in operating conditions is thoroughly analyzed. The results illustrate that the proposed skyhook-based semi-active MR-suspension in the asymmetric mode yields relatively superior dynamic responses to meet the multiple suspension performances of ride, rattle space, road-holding and dynamic tire force transmitted to the pavement, and has desirable robustness on variations in operating conditions of vehicle load and speed and the road roughness. 展开更多
关键词 Magneto-rheological damper Asymmetric damping Semi-active control Vehicle suspension Multi-objective performance
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Asymmetrical traumatic bilateral hip dislocations with hemodynamic instability and an unstable pelvic ring: Case report and review of literature 被引量:4
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作者 Kai Huang Grey Giddins +4 位作者 Jian-Fang Zhang Jian-Wei Lu Jun-Ming Wan Peng-Li Zhang Shao-Yu Zhu 《World Journal of Clinical Cases》 SCIE 2018年第5期94-98,共5页
Simultaneous anterior and posterior traumatic dislocations of both hips are very rare. Only 33 cases have been previously reported in the English language literature. Although they were all due to high-energy injuries... Simultaneous anterior and posterior traumatic dislocations of both hips are very rare. Only 33 cases have been previously reported in the English language literature. Although they were all due to high-energy injuries, they were hemodynamically stable and had a stable pelvic ring. We report a unique case of asymmetrical hip dislocations with an unstable pelvic ring and hemodynamic instability. A 40-year-old man was injured in a high-energy motor vehicle accident. He was hemodynamically unstable when he presented in the emergency department. Radiolographs showed asymmetrical dislocations of both hips with an unstable pelvic ring. Under general anesthesia, he had closed reduction of the dislocations of both hips, followed by temporary stabilization with an external fixator. Transcatheter arterial embolization was performed to stop active pelvic bleeding. Delayed open reduction and internal fixation was performed 12 d later with anterior and posterior plates. The patient recovered well with an uneventful post-operative course. Asymmetrical bilateral hip dislocations with pelvic ring instability caused by trauma, as presented in this case, is very rare and potentially life threatening. Prompt treatment can give a good outcome. 展开更多
关键词 asymmetrical BILATERAL HIP dislocations UNSTABLE PELVIC ring HEMODYNAMIC instability
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Recrystallized microstructural evolution of UFG copper prepared by asymmetrical accumulative rolling-bonding process 被引量:4
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作者 王军丽 史庆南 +2 位作者 钱天才 王绍华 杨喜昆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期559-563,共5页
Copper sheet with grain size of 30-60μm was processed by plastic deformation of asymmetrical accumulative rolling-bonding(AARB)with the strain of 3.2.The effects of annealing temperature and time on microstructural e... Copper sheet with grain size of 30-60μm was processed by plastic deformation of asymmetrical accumulative rolling-bonding(AARB)with the strain of 3.2.The effects of annealing temperature and time on microstructural evolution were studied by means of electron backscattered diffraction(EBSD).EBSD grain mapping,recrystallization pole figure and grain boundary misorientation angle distribution graph were constructed,and the characteristics were assessed by microstructure,grain size,grain boundary misorientation and texture.The results show that ultra fine grains(UFG)are obtained after annealing at 250℃ for 30?40 min.When the annealing is controlled at 250℃for 40 min,the recrystallization is finished,a large number of small grains appear and most grain boundaries consist of low-angle boundaries.The character of texture is rolling texture after the recrystallization treatment,but the strength of the texture is faint.While second recrystallization happens,{110}<1ī2>+{112}<11ī> texture component disappears and turns into{122}<212>cube twin texture component. 展开更多
关键词 severe deformation asymmetrical accumulative rolling-bonding ultra fine grains COPPER
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Automatic Scallion Seedling Feeding Mechanism with an Asymmetrical High-order Transmission Gear Train 被引量:4
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作者 Xiong Zhao Jun Ye +2 位作者 Mengyan Chu Li Dai Jianneng Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第1期148-161,共14页
The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band carriers.It delivers seedlings ine ciently because of the movement limitations of the lin... The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band carriers.It delivers seedlings ine ciently because of the movement limitations of the linkage mechanism.This paper proposes a new high-order non-circular gear train for an automatic scallion-seedling feeding mechanism.The proposed gear train has an asymmetrical transmission ratio;i.e.,its transmission ratio varies.This allows the mechanism’s execution component to move in a long displacement and rotate in a large rotation angle.The long displacement enables the execution component to reach the designed working position,and the large rotation angle allows it to feed a scallion in the required pose.A mathematical model for calculating the asymmetrical transmission ratio was established according to the closure requirements and the full-cycle motion of the driven gear pitch curve.Then,the parameter-design model of the new seedling-feeding mechanism was established,based on precise pose points and trajectory-shape control points.Moreover,an aided-design program was developed to obtain the parameter-solution domain of the scallion-seedling feeding mechanism.The mechanism parameters,which met the seedling-feeding function,were optimized to determine the transmission ratio,using a program and a kinematic simulation.Finally,a prototype of the mechanism was produced,and a seedling-feeding experiment was carried out.One-thousand seedlings were tested at a rate of 100 seedlings per minute,and the statistical success rate was 93.4%.Thus,the automatic scallion-seedling feeding mechanism significantly improves the e ciency of automatically transplanting scallions. 展开更多
关键词 Asymmetric TRANSMISSION Scallion TRANSPLANTING HIGH-ORDER GEAR NON-CIRCULAR GEAR Planetary GEAR train
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Average Cycle Period in Asymmetrical Flashing Ratchet 被引量:3
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作者 WANGHai-Yan HEHou-Sheng BAOJing-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期229-232,共4页
The directed motion of a Brownian particle in a Bashing potential with various transition probabilities and waiting times in one of two states is studied. An expression for the average cycle period is proposed and the... The directed motion of a Brownian particle in a Bashing potential with various transition probabilities and waiting times in one of two states is studied. An expression for the average cycle period is proposed and the steady current J of the particle is calculated via Langevin simulation. The results show that the optimal cycle period (Tm), which takes the maximum of J, is shifted to a small value when the transition probability A from the potential on to the potential off decreases, the maximal current appears in the case of the average waiting time in the potential on being longer than in the potential off, and the direction of current depends on the ratio of the average times waiting in two states. 展开更多
关键词 Brownian motor CURRENT asymmetrical transition
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ASYMMETRICAL STRUCTURES OF THE TEMPERATURE AND HUMIDITY OF TROPICAL CYCLONES 被引量:2
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作者 杨涛 雷小途 汤杰 《Journal of Tropical Meteorology》 SCIE 2016年第3期296-304,共9页
Based on NCEP/CFSR 0.5° reanalysis data and the best track data from the Japan Tokyo Typhoon Center,composite and comparative analyses demonstrate the asymmetrical structures of the temperature and humidity in tr... Based on NCEP/CFSR 0.5° reanalysis data and the best track data from the Japan Tokyo Typhoon Center,composite and comparative analyses demonstrate the asymmetrical structures of the temperature and humidity in tropical cyclones over the Western North Pacific and the South China Sea from 1979 to 2010.The results are shown as follows.(1) With intensifying tropical cyclones,the flow field tends to become gradually more axisymmetric;however,the asymmetry of the specific humidity in the outer regions is more obvious.(2) In general,tropical cyclones have a non-uniform,vertical, "double warm-core" structure.The "warm-cores" in the lower level of weak tropical cyclones and in the higher level of strong tropical cyclones are the stronger of the two.(3) The distribution area of a "warm-core" is enhanced with cyclone intensification and tends to become more axisymmetric.At 200 hPa,the "warm-core" of a weak cyclone has a weak anticyclone in the center,whereas that of a strong cyclone has a weak cyclone in the center.(4)The "wet-core" of a tropical cyclone is primarily located in the lower level(700-850 hPa).With the cyclone's intensification,the intensity of the "wet-core" increases and the scope of the 0.8 g kg^(-1) specific humidity anomaly tends to expand to higher levels.(5) With the cyclone's deepening,the pseudo-equivalent potential temperature at different levels in different regions increases.In addition,the largest warming rates at each intensity level in the different regions occur in the core area,followed in turn by the envelope and outer areas. 展开更多
关键词 TROPICAL CYCLONES asymmetrical structure warm-core wet-core INTENSITY
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Asymmetrical Quantum Encryption Protocol Based on Quantum Search Algorithm 被引量:2
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作者 LUO Wenjun LIU Guanli 《China Communications》 SCIE CSCD 2014年第9期104-111,共8页
Quantum cryptography and quantum search algorithm are considered as two important research topics in quantum information science.An asymmetrical quantum encryption protocol based on the properties of quantum one-way f... Quantum cryptography and quantum search algorithm are considered as two important research topics in quantum information science.An asymmetrical quantum encryption protocol based on the properties of quantum one-way function and quantum search algorithm is proposed.Depending on the no-cloning theorem and trapdoor one-way functions of the publickey,the eavesdropper cannot extract any private-information from the public-keys and the ciphertext.Introducing key-generation randomized logarithm to improve security of our proposed protocol,i.e.,one privatekey corresponds to an exponential number of public-keys.Using unitary operations and the single photon measurement,secret messages can be directly sent from the sender to the receiver.The security of the proposed protocol is proved that it is informationtheoretically secure.Furthermore,compared the symmetrical Quantum key distribution,the proposed protocol is not only efficient to reduce additional communication,but also easier to carry out in practice,because no entangled photons and complex operations are required. 展开更多
关键词 quantum cryptography asymmetrical encryption information-theoreticalsecurity quantum search algorithms
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Analytic Solution of an Asymmetrical Crack in a Strip 被引量:2
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作者 YANG Xiao-chun WANG Lu FAN Tian-you 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第2期117-119,共3页
We present the analytic solution of an asymmetrical crack in a strip from which the stress intensity factors are determined.The results have important application in earthquake source physics and provide information c... We present the analytic solution of an asymmetrical crack in a strip from which the stress intensity factors are determined.The results have important application in earthquake source physics and provide information concerning the instability of faults and the detection of earthquake precursors. 展开更多
关键词 EARTHQUAKE SOURCE asymmetrical
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