Researchers in the field of Second Language Acquisition （SLA） have been taking different routes. Some researchers make linguistic-cognitive issues their inquire object and pursue objectivity with quantitative resear...Researchers in the field of Second Language Acquisition （SLA） have been taking different routes. Some researchers make linguistic-cognitive issues their inquire object and pursue objectivity with quantitative research methods. Other researchers regard the social context of activity as an essential characteristic of learning and teaching. These groups of researchers make use of qualitative research methods like case study, grounded theory, narrative inquiry, and ethnography. There are many other routes that SLA researchers have taken, but the two just mentioned are perhaps the most predominant ones and the ones that are most easily contrasted. The present paper explores the disparity between the different research paths from the perspective of philosophy of science echoing the notion of incommensurability. In this paper the author argues that the differences between different SLA perspectives are not only commensurable but wholesome for the development of SLA.展开更多
In international relations theory （maybe more than in any other discipline of social sciences）, the paradigmatic construction of Thomas Kuhn and his model of incommensurability might be applied to the theoretical in...In international relations theory （maybe more than in any other discipline of social sciences）, the paradigmatic construction of Thomas Kuhn and his model of incommensurability might be applied to the theoretical interpretation of phenomena; and it is one of the cornerstones of the methodological toolkit for the interpretation in this field. The paper explores the reason why Kuhn＇s understanding of incommensurability seems to be necessary for the conception of knowledge in international relations： the concept of incommensurability can be considered typical as it is meant to indicate a conflict, of one form or another, between theories. And the discipline of international relations is more than a perfect ground for considering this concept when one is having in mind the high degree of polarized debate among rivalry theoretical schools （for interpreting and describing the identical phenomena） that is present from the very beginning of the discipline. Recalling the Kuhnian conception of science in paradigmatic view with an aim for understanding--international relations theory, the paper analyzes furthermore his rejection of the traditional dichotomy between “objectivisn”and ＂subjectivism.＂展开更多
Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence ...Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence of the martensitic transformation temperature span on Co content was observed.Before training,quite a narrow temperature span of the martensitic transformation,nearly independent of the Co content,was observed in all single crystals.After training the temperature span was still narrow for 8≤x≤10.9 but was obviously expanded for 10.9<x≤12.High-resolution transmission electron microscopy revealed that at the atomic scale,there exists incommensurate modulated structure in the single phase single crystals,as evidenced by nonperiodic satellite spots in the selected area electronic diffraction patterns.Moreover,the modulated wave vector of the satellite spots was increased by higher Co contents.Combining first principal calculations it was considered that the incommensurate modulated structure originates from the formation of Co-Co pairs.After training arrays of ordered dislocations with the same Burgers vector were introduced for 8≤x≤10.9 but the network of dislocations was formed for 10.9<x≤12.Based on analysis of transmission electron microscopy,geometric phase,thermodynamics,and Landau theory,it was considered that the austenite/martensite phase interface was pinned by the network of dislocations,expanding the temperature span of the martensitic transformation.This work supplies new insights for understanding the microstructure and martensitic transformation of Ni-Mn-Ga-based alloys.展开更多
The dynamic analysis of financial systems is a developing field that combines mathematics and economics to understand and explain fluctuations in financial markets.This paper introduces a new three-dimensional(3D)frac...The dynamic analysis of financial systems is a developing field that combines mathematics and economics to understand and explain fluctuations in financial markets.This paper introduces a new three-dimensional(3D)fractional financial map and we dissect its nonlinear dynamics system under commensurate and incommensurate orders.As such,we evaluate when the equilibrium points are stable or unstable at various fractional orders.We use many numerical methods,phase plots in 2D and 3D projections,bifurcation diagrams and the maximum Lyapunov exponent.These techniques reveal that financial maps exhibit chaotic attractor behavior.This study is grounded on the Caputo-like discrete operator,which is specifically influenced by the variance of the commensurate and incommensurate orders.Furthermore,we confirm the presence and measure the complexity of chaos in financial maps by the 0-1 test and the approximate entropy algorithm.Additionally,we offer nonlinear-type controllers to stabilize the fractional financial map.The numerical results of this study are obtained using MATLAB.展开更多
This paper introduces the idea that if theories of history generate different taxonomies of history they too are incommensurable. I argue this is unavoidable for Kuhn given what he says about incommensurability and 1 ...This paper introduces the idea that if theories of history generate different taxonomies of history they too are incommensurable. I argue this is unavoidable for Kuhn given what he says about incommensurability and 1 investigate the consequences in relation to reflexivity, justification, and paradox for Kuhn＇s account of science. I want to do this on two levels, firstly looking at different possibilities for characterising individual paradigms. I will look at some examples from ancient and early modem astronomy as here it is clearest that paradigms can be characterised in different ways and that this has important consequences. I will argue in particular that Kuhn＇s characterisation of the paradigm for astronomy which emerges from antiquity （geocentrism） is favourable to his general account of the history of science, but that there is a very plausible and extremely damaging alternative. I argue that these differing characterisations generate differing, incommensurable taxonomies of the history of astronomy, with attendant ＂local holism,＂ untranslatability of key terms and issues of theory choice. If so, Kuhn then has problems with generating an adequate decision making protocol for choosing between the two paradigm characterisations. That is problematic in itself, but I also argue this problem is systemic and affects the evidence needed for Kuhn to justify his general account of the history of science. I also want to investigate the implications of differing taxonomies of the history of science at a more abstract level. Kuhn＇s general theory of the history of science generates a taxonomy of the history of science, as do other theories such as those of Popper and of gradualism. If so, the incommensurability involved here, again with attendant ＂local holism,＂ untranslatability of key terms and issues of theory choice, leads to issues of paradox and justification for Kuhn＇s general account of the history of science. With this broader understanding of taxonomic issues, some important Kuhn statements about scientific theories become self-referential, again generating problems of paradox and justification.展开更多
The paper discusses several wide-spread misunderstandings of Kuhn＇s theory of scientific development, most prominently the ascription that he conceives of scientific development as irrational. The core of this ascrip...The paper discusses several wide-spread misunderstandings of Kuhn＇s theory of scientific development, most prominently the ascription that he conceives of scientific development as irrational. The core of this ascription is an assessment of incommensurability as implying the lack of any rational possibility of theory comparison. This is supposed to be due to Gestalt switches and a quasi-religious element of conversion in theory change. Accordingly, scientific revolutions cannot be a serious matter for philosophical analysis; they furthermore foreclose any scientific progress. It is shown that such images of Kuhn＇s theory rest on deep misunderstandings that are partly due to Kuhn＇s writing style.展开更多
In this paper, a fish farm was modeled using the Lexicographic linear goal programming approach due to incommensurability in objectives. The study considered the fish farming plan with two sizes of catfish from stocki...In this paper, a fish farm was modeled using the Lexicographic linear goal programming approach due to incommensurability in objectives. The study considered the fish farming plan with two sizes of catfish from stocking to harvesting at four-month intervals. The multi-objective goals developed are required raw materials feed, water, light (resource utilization), sales revenue, profit realized, labor utilization, production costs, and pond utilization. The developed model was tested using related data collected from the farm records with the use of TORA 2007 software. The compromised solution from the results showed that the developed model is an efficient tool for decision-making process in the fish farm business organization.展开更多
Noncovalent interfaces play a vital role in inelastic deformation and toughening mechanisms in layered nanocomposites due to their dynamical recoverability. When interfacial engineering is applied to design layered na...Noncovalent interfaces play a vital role in inelastic deformation and toughening mechanisms in layered nanocomposites due to their dynamical recoverability. When interfacial engineering is applied to design layered nanocomposites, shear-lag analysis is usually implemented to evaluate the capability of interfacial loading transfer. Here, we introduce a multiscale shear-lag model that correlates macroscale mechanical properties with the molecular mechanisms to quantify the effects of interfacial configuration in graphene oxide(GO) layered nanocomposites. By investigating the mechanical responses of commensurate and incommensurate interfaces, we identify that the commensurate interface exhibits a pronounced size effect due to the nucleation and propagation of interfacial defects, whereas the incommensurate interface displays uniform deformation. Our predictions are further validated through large-scale molecular dynamics simulations for GO layered nanocomposites. This work demonstrates how size effects and interfacial configurations can be exploited to fabricate layered nanocomposites with superior mechanical properties despite relying on weak noncovalent interfaces.展开更多
The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra sec...The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra second neighborhopping t' is systematically accompanied with the increasing of the weight of the incommensurate peaks in the dynamicalspin structure factor, for the physical reasonable small value of t' the qualitative behavior of the incommensurate spincorrelation in the t-t'-J model is the same as in the case of t-J model.展开更多
To identify the relation between torque and superlubric motion, we investigate the interlayer sliding behavior of two graphene disks with numerical computation methods. The potential energy, lateral force and torque b...To identify the relation between torque and superlubric motion, we investigate the interlayer sliding behavior of two graphene disks with numerical computation methods. The potential energy, lateral force and torque between the top and bottom graphene disks, which are associated with misfit angle, translational displacement and interlayer distance, are analyzed. The results show that the rotation of the top disk is feeble for commensurate state, but it is difficult to realize superlubricity due to the lateral force fluctuating remarkably. For incommensurate state, the flake exhibits vanishing torque approaching to zero only for partial sliding directions. The superlubricity between the top and bottom disks will be eliminated due to torque-induced reorientation along other sliding directions. Whether for commensurate or incommensurate contact, the amplitudes of the lateral force （516 pN and 13 pN, respectively） are in qualitative agreement with experimental observation （typically 250 pN and 50 pN, respectively）. It shows that the interlayer torque is insensitive to the top disk size with incommensurate contact. The results suggest that the superlubric motion of graphene disk can be controlled by adjusting the torque.展开更多
A new procedure of trial variational wave functional is proposed for investigating the mass renormalization and the local structure of the ground state of a one-dimensional quantum sine-Gordon model with linear spatia...A new procedure of trial variational wave functional is proposed for investigating the mass renormalization and the local structure of the ground state of a one-dimensional quantum sine-Gordon model with linear spatial modulation, whose ground state differs from that without modulation. The phase diagram obtained in parameters plane shows that the vertical part of the boundary between soliton lattice phase and incommensurate (IC) phase with vanishing gap sticks at , the IC phase can only appear for and the IC phase regime is enlarged with increasing spatial modulation in the case of definite parameter . The transition is of the continuous type on the vertical part of the boundary, while it is of the first order on the boundary for .展开更多
We investigate the magnetic ground state of Sm_(3)BWO_(9)with a distorted kagome lattice.A magnetic phase transition is identified at T_(N)=0.75 K from the temperature dependence of specific heat.From 11B nuclear magn...We investigate the magnetic ground state of Sm_(3)BWO_(9)with a distorted kagome lattice.A magnetic phase transition is identified at T_(N)=0.75 K from the temperature dependence of specific heat.From 11B nuclear magnetic resonance measurements,an incommensurate magnetic order is shown by the double-horn type spectra under a c-axis magnetic field,and absence of line splitting is observed for field oriented within the ab-plane,indicating the incommensurate modulation of the internal field strictly along𝑐c-axis.From the spin dynamics,the critical slowing-down behavior is observed in the temperature dependence of 1/T_(1)with𝜇_(μ0)H⊥c-axis,which is completely absent in the case with𝜇_(μ0)H||c-axis.Based on the local symmetry of 11B sites,we analyze the hyperfine coupling tensors and propose two constraints on the possible magnetic structure.The single ion anisotropy should play an important role in determination of contrasting ground states of Sm_(3)BWO_(9) and Pr_(3)BWO_(9).展开更多
The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra sec...The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra second neighborhopping t' is systematically accompanied with the increasing of the weight of the incommensurate peaks in the dynamicalspin structure factor, for the physical reasonable small value of t' the qualitative behavior of the incommensurate spincorrelation in the t-t'-J model is the same as in the case of t-J model.展开更多
We investigate the synchronization of a class of incommensurate fractional-order chaotic systems, and propose a modified adaptive controller for fractional-order chaos synchronization based on the Lyapunov stability t...We investigate the synchronization of a class of incommensurate fractional-order chaotic systems, and propose a modified adaptive controller for fractional-order chaos synchronization based on the Lyapunov stability theory, the fractional order differential inequality, and the adaptive strategy. This synchronization approach is simple, universal, and theoretically rigorous. It enables the synchronization of O fractional-order chaotic systems to be achieved in a systematic way. The simulation results for the fractional-order Qi chaotic system and the four-wing hyperchaotic system are provided to illustrate the effectiveness of the proposed scheme.展开更多
The microstructural characteristic of the misfit-layered compound PbTiS3 has been studied with transmission electron microscopy. All the incommensurate modulation-induced satellite spots and main diffraction spots of ...The microstructural characteristic of the misfit-layered compound PbTiS3 has been studied with transmission electron microscopy. All the incommensurate modulation-induced satellite spots and main diffraction spots of basic sublattices can be indexed systematically with a superspace group method. Finally, the relationship between the electronic transport properties and the crystal structure is discussed.展开更多
Measurements by using the ultrasonic technique together for electric resistance verified that the first sound velocity valley on cooling is mainly due to the soft-mode of driving the com- mensurate phase transition,an...Measurements by using the ultrasonic technique together for electric resistance verified that the first sound velocity valley on cooling is mainly due to the soft-mode of driving the com- mensurate phase transition,and the second one due to the soft-mode of driving the martensitic transformation.The starting point,R_s,and finishing point,R_f,of the commensurate phase transition of the alloy have been determined.展开更多
Commensurate and incommensurate Haldane phases for a spin-1 bilinear-biquadratic model are investigated using an infinite matrix product state algorithm.The bipartite entanglement entropy can detect a transition point...Commensurate and incommensurate Haldane phases for a spin-1 bilinear-biquadratic model are investigated using an infinite matrix product state algorithm.The bipartite entanglement entropy can detect a transition point between the two phases.In both phases,the entanglement spectrum shows double degeneracy.We calculate the nonlocal order parameter of the bond-centered inversion in both phases,which rapidly approaches a saturation value of-1 as the segment length increases.The nonlocal order parameter of the bond-centered inversion with a saturation value-1 and the nonzero value string order indicate that the Haldane phase is a symmetry-protected topological phase.To distinguish the commensurate and incommensurate Haldane phases,the transversal spin correlation and corresponding momentum distribution of the structure factor are analyzed.As a result,the transversal spin correlations exhibit different decay forms in both phases.展开更多
The aim of this paper is to study complex modified projective synchronization（CMPS） between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate frac...The aim of this paper is to study complex modified projective synchronization（CMPS） between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate fractional-order systems and active control method, control laws are derived to achieve CMPS in three situations including fractional-order complex Lorenz system driving fractional-order complex Chen system, fractional-order real Rssler system driving fractional-order complex Chen system, and fractionalorder complex Lorenz system driving fractional-order real Lü system. Numerical simulations confirm the validity and feasibility of the analytical method.展开更多
In this paper, we present Continuous Multiple Center(CMC) d-p πbond in TS_2 slabs on the basis of Extended Huckle calculation for incommensurate misfit compounds (MS)_xTS_2(where M=Pb, Sn and La; T=V,Nb,Ta, Cr), and ...In this paper, we present Continuous Multiple Center(CMC) d-p πbond in TS_2 slabs on the basis of Extended Huckle calculation for incommensurate misfit compounds (MS)_xTS_2(where M=Pb, Sn and La; T=V,Nb,Ta, Cr), and put forwards the trigonal prismatic coordination CMC d-p π conductive model. According to this model the conductivity of (MS)_xTS_2 series and the similarity between (MS)_xTS_2 and Na_xTS_2 series compounds in metallic behaviors can be explained successfully. Some relations between metallic behaviors and CMC d-p π bond (or band) are found.展开更多
Let x and y be two positive real numbers with x < y. Consider a traveler, on the interval [0, y/2], departing from 0 and taking steps of length equal to x. Every time a step reaches an endpoint of the interval, the...Let x and y be two positive real numbers with x < y. Consider a traveler, on the interval [0, y/2], departing from 0 and taking steps of length equal to x. Every time a step reaches an endpoint of the interval, the traveler rebounds off the endpoint in order to complete the step length. We show that the footprints of the traveler are the output of a full Euclidean algorithm for x and y, whenever y/x is a rational number. In the case that y/x is irrational, the algorithm is, theoretically, not finite;however, it is a new tool for the study of its irrationality.展开更多
文摘Researchers in the field of Second Language Acquisition （SLA） have been taking different routes. Some researchers make linguistic-cognitive issues their inquire object and pursue objectivity with quantitative research methods. Other researchers regard the social context of activity as an essential characteristic of learning and teaching. These groups of researchers make use of qualitative research methods like case study, grounded theory, narrative inquiry, and ethnography. There are many other routes that SLA researchers have taken, but the two just mentioned are perhaps the most predominant ones and the ones that are most easily contrasted. The present paper explores the disparity between the different research paths from the perspective of philosophy of science echoing the notion of incommensurability. In this paper the author argues that the differences between different SLA perspectives are not only commensurable but wholesome for the development of SLA.
文摘In international relations theory （maybe more than in any other discipline of social sciences）, the paradigmatic construction of Thomas Kuhn and his model of incommensurability might be applied to the theoretical interpretation of phenomena; and it is one of the cornerstones of the methodological toolkit for the interpretation in this field. The paper explores the reason why Kuhn＇s understanding of incommensurability seems to be necessary for the conception of knowledge in international relations： the concept of incommensurability can be considered typical as it is meant to indicate a conflict, of one form or another, between theories. And the discipline of international relations is more than a perfect ground for considering this concept when one is having in mind the high degree of polarized debate among rivalry theoretical schools （for interpreting and describing the identical phenomena） that is present from the very beginning of the discipline. Recalling the Kuhnian conception of science in paradigmatic view with an aim for understanding--international relations theory, the paper analyzes furthermore his rejection of the traditional dichotomy between “objectivisn”and ＂subjectivism.＂
基金support from the National Key Research and Development Program of China(Grant No.2021YFB3501402)the National Natural Science Foundation of China(Grant Nos.52250313 and 52121001)Yang Liu and Chen Si acknowledge financial support from the National Natural Science Foundation of China(Grant No.12274013).
文摘Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence of the martensitic transformation temperature span on Co content was observed.Before training,quite a narrow temperature span of the martensitic transformation,nearly independent of the Co content,was observed in all single crystals.After training the temperature span was still narrow for 8≤x≤10.9 but was obviously expanded for 10.9<x≤12.High-resolution transmission electron microscopy revealed that at the atomic scale,there exists incommensurate modulated structure in the single phase single crystals,as evidenced by nonperiodic satellite spots in the selected area electronic diffraction patterns.Moreover,the modulated wave vector of the satellite spots was increased by higher Co contents.Combining first principal calculations it was considered that the incommensurate modulated structure originates from the formation of Co-Co pairs.After training arrays of ordered dislocations with the same Burgers vector were introduced for 8≤x≤10.9 but the network of dislocations was formed for 10.9<x≤12.Based on analysis of transmission electron microscopy,geometric phase,thermodynamics,and Landau theory,it was considered that the austenite/martensite phase interface was pinned by the network of dislocations,expanding the temperature span of the martensitic transformation.This work supplies new insights for understanding the microstructure and martensitic transformation of Ni-Mn-Ga-based alloys.
文摘The dynamic analysis of financial systems is a developing field that combines mathematics and economics to understand and explain fluctuations in financial markets.This paper introduces a new three-dimensional(3D)fractional financial map and we dissect its nonlinear dynamics system under commensurate and incommensurate orders.As such,we evaluate when the equilibrium points are stable or unstable at various fractional orders.We use many numerical methods,phase plots in 2D and 3D projections,bifurcation diagrams and the maximum Lyapunov exponent.These techniques reveal that financial maps exhibit chaotic attractor behavior.This study is grounded on the Caputo-like discrete operator,which is specifically influenced by the variance of the commensurate and incommensurate orders.Furthermore,we confirm the presence and measure the complexity of chaos in financial maps by the 0-1 test and the approximate entropy algorithm.Additionally,we offer nonlinear-type controllers to stabilize the fractional financial map.The numerical results of this study are obtained using MATLAB.
文摘This paper introduces the idea that if theories of history generate different taxonomies of history they too are incommensurable. I argue this is unavoidable for Kuhn given what he says about incommensurability and 1 investigate the consequences in relation to reflexivity, justification, and paradox for Kuhn＇s account of science. I want to do this on two levels, firstly looking at different possibilities for characterising individual paradigms. I will look at some examples from ancient and early modem astronomy as here it is clearest that paradigms can be characterised in different ways and that this has important consequences. I will argue in particular that Kuhn＇s characterisation of the paradigm for astronomy which emerges from antiquity （geocentrism） is favourable to his general account of the history of science, but that there is a very plausible and extremely damaging alternative. I argue that these differing characterisations generate differing, incommensurable taxonomies of the history of astronomy, with attendant ＂local holism,＂ untranslatability of key terms and issues of theory choice. If so, Kuhn then has problems with generating an adequate decision making protocol for choosing between the two paradigm characterisations. That is problematic in itself, but I also argue this problem is systemic and affects the evidence needed for Kuhn to justify his general account of the history of science. I also want to investigate the implications of differing taxonomies of the history of science at a more abstract level. Kuhn＇s general theory of the history of science generates a taxonomy of the history of science, as do other theories such as those of Popper and of gradualism. If so, the incommensurability involved here, again with attendant ＂local holism,＂ untranslatability of key terms and issues of theory choice, leads to issues of paradox and justification for Kuhn＇s general account of the history of science. With this broader understanding of taxonomic issues, some important Kuhn statements about scientific theories become self-referential, again generating problems of paradox and justification.
文摘The paper discusses several wide-spread misunderstandings of Kuhn＇s theory of scientific development, most prominently the ascription that he conceives of scientific development as irrational. The core of this ascription is an assessment of incommensurability as implying the lack of any rational possibility of theory comparison. This is supposed to be due to Gestalt switches and a quasi-religious element of conversion in theory change. Accordingly, scientific revolutions cannot be a serious matter for philosophical analysis; they furthermore foreclose any scientific progress. It is shown that such images of Kuhn＇s theory rest on deep misunderstandings that are partly due to Kuhn＇s writing style.
文摘In this paper, a fish farm was modeled using the Lexicographic linear goal programming approach due to incommensurability in objectives. The study considered the fish farming plan with two sizes of catfish from stocking to harvesting at four-month intervals. The multi-objective goals developed are required raw materials feed, water, light (resource utilization), sales revenue, profit realized, labor utilization, production costs, and pond utilization. The developed model was tested using related data collected from the farm records with the use of TORA 2007 software. The compromised solution from the results showed that the developed model is an efficient tool for decision-making process in the fish farm business organization.
基金jointly supported by the National Natural Science Foundation of China(Nos.11872063 and 12172346)the University of Science and Technology of China(USTC)Research Funds of the Double First-Class Initiative(No.YD2480002002)China Postdoctoral Science Foundation(No.2021TQ0323)。
文摘Noncovalent interfaces play a vital role in inelastic deformation and toughening mechanisms in layered nanocomposites due to their dynamical recoverability. When interfacial engineering is applied to design layered nanocomposites, shear-lag analysis is usually implemented to evaluate the capability of interfacial loading transfer. Here, we introduce a multiscale shear-lag model that correlates macroscale mechanical properties with the molecular mechanisms to quantify the effects of interfacial configuration in graphene oxide(GO) layered nanocomposites. By investigating the mechanical responses of commensurate and incommensurate interfaces, we identify that the commensurate interface exhibits a pronounced size effect due to the nucleation and propagation of interfacial defects, whereas the incommensurate interface displays uniform deformation. Our predictions are further validated through large-scale molecular dynamics simulations for GO layered nanocomposites. This work demonstrates how size effects and interfacial configurations can be exploited to fabricate layered nanocomposites with superior mechanical properties despite relying on weak noncovalent interfaces.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10125415, 10074007, 90103024, and NationalScience Council under Grant No. NSC 90-2816-M-032-0001-6
文摘The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra second neighborhopping t' is systematically accompanied with the increasing of the weight of the incommensurate peaks in the dynamicalspin structure factor, for the physical reasonable small value of t' the qualitative behavior of the incommensurate spincorrelation in the t-t'-J model is the same as in the case of t-J model.
基金Supported by the National Basic Research Program of China(973 Program)(2013CB934200)the Key Program of the National Natural Science Foundation of China(10832005)the National Natural Science Foundation of China(11264030)
文摘To identify the relation between torque and superlubric motion, we investigate the interlayer sliding behavior of two graphene disks with numerical computation methods. The potential energy, lateral force and torque between the top and bottom graphene disks, which are associated with misfit angle, translational displacement and interlayer distance, are analyzed. The results show that the rotation of the top disk is feeble for commensurate state, but it is difficult to realize superlubricity due to the lateral force fluctuating remarkably. For incommensurate state, the flake exhibits vanishing torque approaching to zero only for partial sliding directions. The superlubricity between the top and bottom disks will be eliminated due to torque-induced reorientation along other sliding directions. Whether for commensurate or incommensurate contact, the amplitudes of the lateral force （516 pN and 13 pN, respectively） are in qualitative agreement with experimental observation （typically 250 pN and 50 pN, respectively）. It shows that the interlayer torque is insensitive to the top disk size with incommensurate contact. The results suggest that the superlubric motion of graphene disk can be controlled by adjusting the torque.
文摘A new procedure of trial variational wave functional is proposed for investigating the mass renormalization and the local structure of the ground state of a one-dimensional quantum sine-Gordon model with linear spatial modulation, whose ground state differs from that without modulation. The phase diagram obtained in parameters plane shows that the vertical part of the boundary between soliton lattice phase and incommensurate (IC) phase with vanishing gap sticks at , the IC phase can only appear for and the IC phase regime is enlarged with increasing spatial modulation in the case of definite parameter . The transition is of the continuous type on the vertical part of the boundary, while it is of the first order on the boundary for .
基金supported by the National Natural Science Foundation of China (Grants No.11874057,11874158,U1732273,and 21927814)the High Magnetic Field Laboratory of Anhui Province
文摘We investigate the magnetic ground state of Sm_(3)BWO_(9)with a distorted kagome lattice.A magnetic phase transition is identified at T_(N)=0.75 K from the temperature dependence of specific heat.From 11B nuclear magnetic resonance measurements,an incommensurate magnetic order is shown by the double-horn type spectra under a c-axis magnetic field,and absence of line splitting is observed for field oriented within the ab-plane,indicating the incommensurate modulation of the internal field strictly along𝑐c-axis.From the spin dynamics,the critical slowing-down behavior is observed in the temperature dependence of 1/T_(1)with𝜇_(μ0)H⊥c-axis,which is completely absent in the case with𝜇_(μ0)H||c-axis.Based on the local symmetry of 11B sites,we analyze the hyperfine coupling tensors and propose two constraints on the possible magnetic structure.The single ion anisotropy should play an important role in determination of contrasting ground states of Sm_(3)BWO_(9) and Pr_(3)BWO_(9).
文摘The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra second neighborhopping t' is systematically accompanied with the increasing of the weight of the incommensurate peaks in the dynamicalspin structure factor, for the physical reasonable small value of t' the qualitative behavior of the incommensurate spincorrelation in the t-t'-J model is the same as in the case of t-J model.
基金Project supported by the Natural Science Foundation of Hebei Province, China （Grant No. A2010000343）.
文摘We investigate the synchronization of a class of incommensurate fractional-order chaotic systems, and propose a modified adaptive controller for fractional-order chaos synchronization based on the Lyapunov stability theory, the fractional order differential inequality, and the adaptive strategy. This synchronization approach is simple, universal, and theoretically rigorous. It enables the synchronization of O fractional-order chaotic systems to be achieved in a systematic way. The simulation results for the fractional-order Qi chaotic system and the four-wing hyperchaotic system are provided to illustrate the effectiveness of the proposed scheme.
基金Project supported by the National Basic Research Program of China(Grant No.2012CB932302)the National Natural Science Foundation of China(Grant No.50921091)the Specific Funding of the Discipline and Graduate Education Project of Beijing Municipal Commission of Education,China
文摘The microstructural characteristic of the misfit-layered compound PbTiS3 has been studied with transmission electron microscopy. All the incommensurate modulation-induced satellite spots and main diffraction spots of basic sublattices can be indexed systematically with a superspace group method. Finally, the relationship between the electronic transport properties and the crystal structure is discussed.
文摘Measurements by using the ultrasonic technique together for electric resistance verified that the first sound velocity valley on cooling is mainly due to the soft-mode of driving the com- mensurate phase transition,and the second one due to the soft-mode of driving the martensitic transformation.The starting point,R_s,and finishing point,R_f,of the commensurate phase transition of the alloy have been determined.
基金the National Natural Science Foundation of China(Grant No.11805285)the Natural Science Foundation of Shaanxi Province of China(Grant No.2022JM-033)the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJQN 201900703)。
文摘Commensurate and incommensurate Haldane phases for a spin-1 bilinear-biquadratic model are investigated using an infinite matrix product state algorithm.The bipartite entanglement entropy can detect a transition point between the two phases.In both phases,the entanglement spectrum shows double degeneracy.We calculate the nonlocal order parameter of the bond-centered inversion in both phases,which rapidly approaches a saturation value of-1 as the segment length increases.The nonlocal order parameter of the bond-centered inversion with a saturation value-1 and the nonzero value string order indicate that the Haldane phase is a symmetry-protected topological phase.To distinguish the commensurate and incommensurate Haldane phases,the transversal spin correlation and corresponding momentum distribution of the structure factor are analyzed.As a result,the transversal spin correlations exhibit different decay forms in both phases.
基金supported by Key Program of National Natural Science Foundation of China (No. 61533011)National Natural Science Foundation of China (Nos. 61273088 and 61603203)
文摘The aim of this paper is to study complex modified projective synchronization（CMPS） between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate fractional-order systems and active control method, control laws are derived to achieve CMPS in three situations including fractional-order complex Lorenz system driving fractional-order complex Chen system, fractional-order real Rssler system driving fractional-order complex Chen system, and fractionalorder complex Lorenz system driving fractional-order real Lü system. Numerical simulations confirm the validity and feasibility of the analytical method.
文摘In this paper, we present Continuous Multiple Center(CMC) d-p πbond in TS_2 slabs on the basis of Extended Huckle calculation for incommensurate misfit compounds (MS)_xTS_2(where M=Pb, Sn and La; T=V,Nb,Ta, Cr), and put forwards the trigonal prismatic coordination CMC d-p π conductive model. According to this model the conductivity of (MS)_xTS_2 series and the similarity between (MS)_xTS_2 and Na_xTS_2 series compounds in metallic behaviors can be explained successfully. Some relations between metallic behaviors and CMC d-p π bond (or band) are found.
文摘Let x and y be two positive real numbers with x < y. Consider a traveler, on the interval [0, y/2], departing from 0 and taking steps of length equal to x. Every time a step reaches an endpoint of the interval, the traveler rebounds off the endpoint in order to complete the step length. We show that the footprints of the traveler are the output of a full Euclidean algorithm for x and y, whenever y/x is a rational number. In the case that y/x is irrational, the algorithm is, theoretically, not finite;however, it is a new tool for the study of its irrationality.
