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SIEMENS 802D和FANUC 0数控系统子程序应用对比分析
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作者 陈海燕 《邢台职业技术学院学报》 2008年第3期41-42,共2页
采用对比的方法,介绍了SIEMENS 802D和FANUC 0系列数控系统在子程序应用中的异同点,通过对子程序命名、子程序结束指令及子程序调用的对比分析,编程人员对这两种系统的子程序应用一目了然,进而避免出现一些编程失误。
关键词 SIEMENS 802D FANUC 0系列 子程序应用
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“子程序的应用”的教学设计
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作者 张守燕 《职教通讯(江苏技术师范学院学报)》 2009年第4期62-63,共2页
以建构主义学习理论为指导设计"子程序的应用"的教学方案,通过创设学习情境。引导学生在协作、探究等主体活动中主动建构知识意义,实现教学三维目标。
关键词 子程序应用 教学设计
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Subtree, TASS and an Analysis of the Genus Caragana
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作者 张明理 Pauline Y. LADIGES Gareth NELSON 《Acta Botanica Sinica》 CSCD 2002年第10期1213-1218,共6页
Subtree analysis and three area satements (TASS) procedure are used to deal with the area relationship in historical biogeography. On the basis of the taxon cladogram, the procedure could identify and eliminate the ... Subtree analysis and three area satements (TASS) procedure are used to deal with the area relationship in historical biogeography. On the basis of the taxon cladogram, the procedure could identify and eliminate the paralogy node and determine the informative subtree. The area relationships are generally illustrated in several subtrees and the consensus tree. The distribution pattern of the genus Caragana comprising about 72 species and occurring in 13 areas, was analyzed by using subtree method and TASS procedure in this study. The results showed seven subtrees representing the area relationships of section and series of the genus, and the consensus tree provided the 13 area relationships. These results are congruent with our former result using component analysis for Caragana. 展开更多
关键词 SUBTREE three area satements (TASS) CARAGANA distribution pattern
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HiQoS:An SDN-Based Multipath QoS Solution 被引量:21
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作者 YAN Jinyao ZHANG Hailong +2 位作者 SHUAI Qianjun LIU Bo GUO Xiao 《China Communications》 SCIE CSCD 2015年第5期123-133,共11页
Today's Internet architecture provides only "best effort" services,thus it cannot guarantee quality of service(QoS) for applications.Software Defined Network(SDN)is a new approach to computer networking ... Today's Internet architecture provides only "best effort" services,thus it cannot guarantee quality of service(QoS) for applications.Software Defined Network(SDN)is a new approach to computer networking that separates control plane and forwarding planes,and has the advantage of centralized control and programmability.In this paper,we propose HiQoS that provides QoS guarantees using SDN.Moreover,HiQoS makes use of multiple paths between source and destination and queuing mechanisms to guarantee QoS for different types of traffic.Experimental results show that our HiQoS scheme can reduce delay and increase throughput to guarantee QoS.Very importantly,HiQoS recovers from link failure very quickly by rerouting traffic from failed path to other available path. 展开更多
关键词 SDN QOS MULTIPATH OpenFlow
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ESTIMATION METHOD OF AIRSPACE CONNECTIVITY PROBABILITY IN MILITARY AANET 被引量:2
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作者 Luo Changyuan Song Yulong Pang Songchao 《Journal of Electronics(China)》 2013年第6期538-546,共9页
Connectivity is the premise and foundation of networking and routing.For the probabilistic flight path of military aircraft resulting in the difficulty of Aeronautical Ad hoc NETwork(AANET) research,an estimation meth... Connectivity is the premise and foundation of networking and routing.For the probabilistic flight path of military aircraft resulting in the difficulty of Aeronautical Ad hoc NETwork(AANET) research,an estimation method of connectivity probability is proposed.The method takes airspace as the research object,starts with actual flight characteristics,and applies conclusions of random waypoint mobility model.Building a connectivity model by establishing Airspace Unit Circle(AUC) from the perspective of circle-circle coverage,the method obtains a theory of airspace network connectivity.Experiment demonstrates its correctness.Finally,according to the actual condition simulation,relationship between the number of aircraft,communication radius,and the flight area under connectivity probabilities is achieved,results provide reference for creating a network that under certain aerial combat condition. 展开更多
关键词 Aeronautical ad hoc network (AANET) Military aviation Mobility model Con-nectivity Airspace Unit Circle (AUC)
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A novel internet traffic identification approach using wavelet packet decomposition and neural network 被引量:6
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作者 谭骏 陈兴蜀 +1 位作者 杜敏 朱锴 《Journal of Central South University》 SCIE EI CAS 2012年第8期2218-2230,共13页
Internet traffic classification plays an important role in network management, and many approaches have been proposed to classify different kinds of internet traffics. A novel approach was proposed to classify network... Internet traffic classification plays an important role in network management, and many approaches have been proposed to classify different kinds of internet traffics. A novel approach was proposed to classify network applications by optimized back-propagation (BP) neural network. Particle swarm optimization (PSO) algorithm was used to optimize the BP neural network. And in order to increase the identification performance, wavelet packet decomposition (WPD) was used to extract several hidden features from the time-frequency information of network traffic. The experimental results show that the average classification accuracy of various network applications can reach 97%. Moreover, this approach optimized by BP neural network takes 50% of the training time compared with the traditional neural network. 展开更多
关键词 neural network particle swarm optimization statistical characteristic traffic identification wavelet packet decomposition
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Application of the DEM to screening process:a 3D simulation 被引量:17
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作者 CHEN Yan-hua TONG Xin 《Mining Science and Technology》 EI CAS 2009年第4期493-497,共5页
The discrete element method(DEM) has been widely used to simulate microscopic interactions between particles.Screening is a deeply complicated process when considering the law of motion for the particles,themselves.In... The discrete element method(DEM) has been widely used to simulate microscopic interactions between particles.Screening is a deeply complicated process when considering the law of motion for the particles,themselves.In this paper,a numerical model for the study of a particle screening process using the DEM is presented.Special attention was paid to the modeling of a vibrating screen that allows particles to pass through,or to rebound,when approaching the screen surface.Inferences concerning screen length and vibrating frequency as they relate to screening efficiency were studied.The conclusions were:three-dimensional simulation of screening efficiency along the screen length follows an exponential distribution;when the sieve vibrates over a certain frequency range the screening efficiency is stable;and,higher vibration frequencies can improve the handling capacity of the screening machine. 展开更多
关键词 discrete element method screening efficiency digital simulation
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AN ADAPTIVE-WEIGHTED TWO-DIMENSIONAL DATA AGGREGATION ALGORITHM FOR CLUSTERED WIRELESS SENSOR NETWORKS
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作者 Zhang Junhu Zhu Xiujuan Peng Hui 《Journal of Electronics(China)》 2013年第6期525-537,共13页
In this paper,an Adaptive-Weighted Time-Dimensional and Space-Dimensional(AWTDSD) data aggregation algorithm for a clustered sensor network is proposed for prolonging the lifetime of the network as well as improving t... In this paper,an Adaptive-Weighted Time-Dimensional and Space-Dimensional(AWTDSD) data aggregation algorithm for a clustered sensor network is proposed for prolonging the lifetime of the network as well as improving the accuracy of the data gathered in the network.AWTDSD contains three phases:(1) the time-dimensional aggregation phase for eliminating the data redundancy;(2) the adaptive-weighted aggregation phase for further aggregating the data as well as improving the accuracy of the aggregated data; and(3) the space-dimensional aggregation phase for reducing the size and the amount of the data transmission to the base station.AWTDSD utilizes the correlations between the sensed data for reducing the data transmission and increasing the data accuracy as well.Experimental result shows that AWTDSD can not only save almost a half of the total energy consumption but also greatly increase the accuracy of the data monitored by the sensors in the clustered network. 展开更多
关键词 Data aggregation Adaptive-weighted aggregation Clustered Wireless Sensor Networks(WSNs) Linear regression Data accuracy Energy consumption Lempel-Ziv-Welch (LZW)
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AN IDENTITY-BASED KEY AGREEMENT SCHEME FOR LARGE SCALE SENSOR NETWORKS
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作者 Yang Lijun Wu Meng Ding Chao 《Journal of Electronics(China)》 2013年第6期574-586,共13页
To solve the problems of high memory occupation, low connectivity and poor resiliency against node capture, which existing in the random key pre-distribution techniques while applying to the large scale Wireless Senso... To solve the problems of high memory occupation, low connectivity and poor resiliency against node capture, which existing in the random key pre-distribution techniques while applying to the large scale Wireless Sensor Networks (WSNs), an Identity-Based Key Agreement Scheme (IBKAS) is proposed based on identity-based encryption and Elliptic Curve Diffie-Hellman (ECDH). IBKAS can resist man-in-the-middle attacks and node-capture attacks through encrypting the key agreement parameters using identity-based encryption. Theoretical analysis indicates that comparing to the random key pre-distribution techniques, IBKAS achieves significant improvement in key connectivity, communication overhead, memory occupation, and security strength, and also enables efficient secure rekcying and network expansion. Furthermore, we implement IBKAS for TinyOS-2.1.2 based on the MICA2 motes, and the experiment results demonstrate that IBKAS is feasible for infrequent key distribution and rekeying for large scale sensor networks. 展开更多
关键词 Large scale Wireless Sensor Networks (WSNs) Network security Key agreement Iden-tity-based cryptography
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Calculation of the Energy Distribution of Electrons Emitted from Tungsten
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《Journal of Physical Science and Application》 2013年第3期141-146,共6页
The numerical calculation of the energy distribution of electrons emitted by the tungsten, for a triangular barrier and given reflection images, has been carried out. It is shown that the numerical solution of Schrodi... The numerical calculation of the energy distribution of electrons emitted by the tungsten, for a triangular barrier and given reflection images, has been carried out. It is shown that the numerical solution of Schrodinger equation is the most effective method of calculation of the transparency of potential barrier among those used in work. I-V characteristics, which were calculated by the application of this method under different conditions, match the experimental data the best. The application of the numerical solution of Schrodinger equation for the calculation of transparency of the potential barrier enables the in-depth analysis of the tunnels phenomena and allows forecasting the effects which can not be received by application of Wentzel-Kramers-Brillouin approximation. 展开更多
关键词 Field emission transparency of potential barrier energy distribution of electrons.
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Comparative systems biology between human and animal models based on next-generation sequencing methods
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作者 Yu-Qi ZHAO Gong-Hua LI Jing-Fei HUANG 《Zoological Research》 CAS CSCD 北大核心 2013年第2期J0001-J0007,共7页
Animal models provide myriad benefits to both experimental and clinical research. Unfortunately, in many situations, they fall short of expected results or provide contradictory results. In part, this can be the resul... Animal models provide myriad benefits to both experimental and clinical research. Unfortunately, in many situations, they fall short of expected results or provide contradictory results. In part, this can be the result of traditional molecular biological approaches that are relatively inefficient in elucidating underlying molecular mechanism. To improve the efficacy of animal models, a technological breakthrough is required. The growing availability and application of the high-throughput methods make systematic comparisons between human and animal models easier to perform. In the present study, we introduce the concept of the comparative systems biology, which we define as "comparisons of biological systems in different states or species used to achieve an integrated understanding of life forms with all their characteristic complexity of interactions at multiple levels". Furthermore, we discuss the applications of RNA-seq and ChIP-seq technologies to comparative systems biology between human and animal models and assess the potential applications for this approach in the future studies. 展开更多
关键词 Animal models Comparative systems biology Next-generation sequencing RNA-SEQ ChlP-seq
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Self-organization of Atoms into Nanosystems
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作者 Titorov Dmitriy 《Journal of Chemistry and Chemical Engineering》 2012年第9期809-813,共5页
The mechanism of addition of separate atoms to a growing center is considered with application of model of a pair interpenetration of atoms. Features of geometrical model are related with the electronic structure of a... The mechanism of addition of separate atoms to a growing center is considered with application of model of a pair interpenetration of atoms. Features of geometrical model are related with the electronic structure of atoms and the Pauli's exclusion principle. The forces providing self-organization of atoms in the bulk of a condensed substance are shown. The calculated interatomic distances in graphite and alloys of gold with silver coincide with those known from experiments with accuracy of 0.1%. 展开更多
关键词 Pair interpenetration Pauli's exclusion principle interatomic forces SELF-ORGANIZATION interatomic distances graphite AuAg alloys.
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Vibration of 1000-MW Ultra-Supercritical Turbine-Generator Unit with Simens Technology
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作者 Zhang Xueyan Zhang Weijun Ge Xiang He Guoan 《Electricity》 2012年第5期48-54,58,共8页
The layout features of unit shafting and their effects on vibration, as well as evaluation criteria, were introduced for a 1000-MW ultra-supercritical turbine-generator unit with Simens technology. Based on vibration ... The layout features of unit shafting and their effects on vibration, as well as evaluation criteria, were introduced for a 1000-MW ultra-supercritical turbine-generator unit with Simens technology. Based on vibration diagnosis and treatment for more than 10 units, some typical vibration faults were summarized, such as the vibration fluctuation of the high pressure (HP) rotor, abnormal vibration increases of the No.3 bearing pedestal and large vibration of the exciter rotor during its critical speed range. The vibration characteristics and the causes of faults and countermeasures were analyzed. Three applications for further illustration were given. The vibration fault identification method, control measures, and applications can provide a reference for vibration diagnoses and treatment of same type units. 展开更多
关键词 1 000-MW ultra-supercritical unit VIBRATION single bearing support rotor (thermal) unbalance rotor dynamic (thermal) balance
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A proximal point algorithm revisit on the alternating direction method of multipliers 被引量:23
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作者 CAI XingJu GU GuoYong +1 位作者 HE BingSheng YUAN XiaoMing 《Science China Mathematics》 SCIE 2013年第10期2179-2186,共8页
The alternating direction method of multipliers(ADMM)is a benchmark for solving convex programming problems with separable objective functions and linear constraints.In the literature it has been illustrated as an app... The alternating direction method of multipliers(ADMM)is a benchmark for solving convex programming problems with separable objective functions and linear constraints.In the literature it has been illustrated as an application of the proximal point algorithm(PPA)to the dual problem of the model under consideration.This paper shows that ADMM can also be regarded as an application of PPA to the primal model with a customized choice of the proximal parameter.This primal illustration of ADMM is thus complemental to its dual illustration in the literature.This PPA revisit on ADMM from the primal perspective also enables us to recover the generalized ADMM proposed by Eckstein and Bertsekas easily.A worst-case O(1/t)convergence rate in ergodic sense is established for a slight extension of Eckstein and Bertsekas’s generalized ADMM. 展开更多
关键词 alternating direction method of multipliers convergence rate convex programming proximalpoint algorithm
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Artificial molecular machines that can perform work 被引量:5
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作者 Qiaochun Wang Dizhi Chen He Tian 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第10期1261-1273,共13页
An artificial molecular machine consists of molecule or substituent components jointed together in a specific way so that their mutual displacements could be initiated using appropriate outside stimuli. Such an abilit... An artificial molecular machine consists of molecule or substituent components jointed together in a specific way so that their mutual displacements could be initiated using appropriate outside stimuli. Such an ability of performing mechanical motions by consuming external energy has endowed these tiny machines with vast fascinating potential applications in areas such as actuators, manipulating atoms/molecules, drug delivery, molecular electronic devices, etc. To date, although vast kinds of molecular machine archetypes have been synthesized in facile ways, they are inclined to be defined as switches but not true machines in most cases because no useful work has been done during a working cycle. More efforts need to be devoted on the utilization and amplification of the nanoscale mechanical motions among synthetic molecular machines to accomplish useful tasks. Here we highlight some of the recent advances relating to molecular machines that can perform work on different length scales, ranging from microscopic levels to macroscopic ones. 展开更多
关键词 molecular machines molecular motors ROTAXANES CATENANES switches
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Theranostic nanomedicine by surface nanopore engineering 被引量:4
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作者 Zhenli Li Luodan Yu +1 位作者 Tian Yang Yu Chen 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第10期1243-1260,共18页
Theranostic nanomedicine that integrates diagnostic and therapeutic agents into one nanosystem has gained considerable momentum in the field of cancer treatment. Among diverse strategies for achieving theranostic capa... Theranostic nanomedicine that integrates diagnostic and therapeutic agents into one nanosystem has gained considerable momentum in the field of cancer treatment. Among diverse strategies for achieving theranostic capabilities, surface-nanopore engineering based on mesoporous silica coating has attracted great interest because of their negligible cytotoxicity and chemically active surface that can be easily modified to introduce various functional groups(e.g.,-COOH,-NH_2,-SH, etc.) via silanization, which can satisfy various requirements of conjugating biological molecules or functional nanoparticles. In addition,the nanopore-engineered biomaterials possess large surface area and high pore volume, ensuring desirable loading of therapeutic guest molecules. In this review, we comprehensively summarize the synthetic procedure/paradigm of nanopore engineering and further broad theranostic applications. Such nanopore-engineering strategy endows the biocompatible nanocomposites(e.g., Au,Ag, graphene, upconversion nanoparticles, Fe_3O_4, MXene, etc.) with versatile functional moieties, which enables the development of multifunctional nanoplatforms for multimodal diagnostic bio-imaging, photothermal therapy, photodynamic therapy,targeted drug delivery, synergetic therapy and imaging-guided therapies. Therefore, mesoporous silica-based surface-nanopore engineering integrates intriguing unique features for broadening the biomedical applications of the single mono-functional nanosystem, facilitating the development and further clinical translation of theranostic nanomedicine. 展开更多
关键词 mesoporous silica nanopore engineering THERANOSTIC CANCER NANOMEDICINE
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Polyoxometalate-based ionic liquids-promoted CO_2 conversion 被引量:3
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作者 Mei-Yan Wang Ran Ma Liang-Nian He 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第5期507-516,共10页
Polyoxometalates(POMs) are a class of molecular metal oxides, showing numerous applications in various chemical processes due to their unique acid/base and redox features. By adjusting the tunable molecular structures... Polyoxometalates(POMs) are a class of molecular metal oxides, showing numerous applications in various chemical processes due to their unique acid/base and redox features. By adjusting the tunable molecular structures of the anions and counter cations, plenty of POM-based ionic liquids(POM-based ILs) have been fabricated to be used in various fields, such as catalysis, structural chemistry and material science. As a class of excellent catalysts, POM-based ILs have shown advantages in the emerging field of CO_2 utilization such as CO_2 capture, cycloaddition of CO_2 to epoxides, and reduction of CO_2, owing to the efficient activation of CO_2 by POM anions. This review summarizes recent advances in the catalysis of POM-based ILs, and particularly highlights the areas that are related to CO_2 conversion. 展开更多
关键词 ionic liquid CATALYSIS CO2 conversion POLYOXOMETALATE
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The preparation of supported ionic liquids (SILs) and their application in rare metals separation 被引量:4
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作者 ZHU LiLi GUO Lin +2 位作者 ZHANG ZhenJiang CHEN Ji ZHANG ShaoMin 《Science China Chemistry》 SCIE EI CAS 2012年第8期1479-1487,共9页
This review summarizes the preparation methods of support ionic liquids (SILs) and their applications in rare metals separation The rare metals separation includes the recovery of high value metal ions and the remov... This review summarizes the preparation methods of support ionic liquids (SILs) and their applications in rare metals separation The rare metals separation includes the recovery of high value metal ions and the removal of heavy metal ions from wastewater. SILs can be used as a kind of highly efficient multifunctional separation materials. The preparation methods of SILs include chemical immobilization technique in which ILs moieties are supported on solid supports via covalent bonds and physical immobilization techniques in which ILs are immobilized on solid supports via physical method such as simple im- pregnation, sol-gel method. According to the difference of solid supports, this review summarizes the application of polymer supported ionic liquids (P-SILs), silica based material supported ionic liquids (SM-SILs) and membrane supported ionic liq- uids (M-SILs) in rare metals separation, P-SILs and SM-SILs prepared by chemical method with N-methylimidazolium group can be used as highly efficient anion exchangers with high thermal stability and good chemical stability for adsorption of Cr(Ⅵ), Re(Ⅶ), Ce(Ⅳ). P-SILs prepared via simple impregnation afforded IL functionalized solvent impregnated resins (SIRs) which showed high separation efficiency and selectivity in the separation of rare earths(Ⅲ) (REs(Ⅲ)). SM-SILs prepared via sol-gel method with IL doped in the support as porogens or extractant show high removal efficiencies and excellent stability for the separation of RE(Ⅲ), Cr(Ⅲ) and Cr(Ⅵ). M-SILs with IL as plasticizer or carrier show improved stability, high perme- ability coefficient and good selectivity for Cr(VI) transport. Different supports and different supporting methods were suffi- ciently compared. Based on the different practical application, different forms of SILs can be prepared for separation of rare metals with high separation efficiency and selectivity. 展开更多
关键词 supported ionic liquid SEPARATION rare metals rare earth CHROMIUM
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Tight-binding models for ultracold atoms in optical lattices:general formulation and applications 被引量:1
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作者 Michele Modugno Julen Ibanez-Azpiroz Giulio Pettini 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第6期1-23,共23页
Tight-binding models for ultracold atoms in optical lattices can be properly defined by using the concept of maximally localized Wannier functions for composite bands. The basic principles of this approach are reviewe... Tight-binding models for ultracold atoms in optical lattices can be properly defined by using the concept of maximally localized Wannier functions for composite bands. The basic principles of this approach are reviewed here, along with different applications to lattice potentials with two minima per unit cell, in one and two spatial dimensions. Two independent methods for computing the tight-binding coefficients—one ab initio, based on the maximally localized Wannier functions, the other through analytic expressions in terms of the energy spectrum—are considered. In the one dimensional case, where the tight-binding coefficients can be obtained by designing a specific gauge transformation, we consider both the case of quasi resonance between the two lowest bands, and that between s and p orbitals. In the latter case, the role of the Wannier functions in the derivation of an effective Dirac equation is also reviewed. Then, we consider the case of a two dimensional honeycomb potential, with particular emphasis on the Haldane model, its phase diagram, and the breakdown of the Peierls substitution. Tunable honeycomb lattices, characterized by movable Dirac points, are also considered. Finally, general considerations for dealing with the interaction terms are presented. 展开更多
关键词 ultracold atoms optical lattices tight-binding models Wannier functions effective Dirac equation honeycomb lattices
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Lanthanide complexes mediated coordinative chain transfer polymerization of conjugated dienes 被引量:3
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作者 WANG Feng LIU Heng +1 位作者 HU YanMing ZHANG XueQuan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第9期1286-1294,共9页
Tremendous advances has been witnessed in the past few years in the lanthanide complexes mediated coordinative chain transfer polymerization(CCTP) of conjugated dienes. CCTP features catalyst economy, well-controlling... Tremendous advances has been witnessed in the past few years in the lanthanide complexes mediated coordinative chain transfer polymerization(CCTP) of conjugated dienes. CCTP features catalyst economy, well-controlling over both microstructure and architecture of the resulting polymers, and accessibility for novel(co)polymers. This review highlights the recent progresses made in the field of CCTP of dienes. After a brief introduction, the body of this review is divided into three parts:(1) principle of CCTP;(2) coordinative chain transfer homopolymerization of dienes;(3) coordinative chain transfer copolymerization of dienes.At the end, we present some challenges remaining in this area and our personal opinion regarding where this field should continue to develop. CCTP represents a novel strategy to prepare polydiene synthetic rubbers with controlled high molecular weight and narrow molecular weight distribution, which has reached the practical industrial application level, demonstrating a great potential in industrialization. 展开更多
关键词 coordinative chain transfer polymerization DIENES lanthanide complexes
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