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Physical energies to the rescue of damaged tissues 预览
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作者 Federica Facchin Silvia Canaider +7 位作者 Riccardo Tassinari Chiara Zannini Eva Bianconi Valentina Taglioli Elena Olivi Claudia Cavallini Marco Tausel Carlo Ventura 《世界干细胞杂志:英文版(电子版)》 2019年第6期297-321,共25页
Rhythmic oscillatory patterns sustain cellular dynamics, driving the concerted action of regulatory molecules, microtubules, and molecular motors. We describe cellular microtubules as oscillators capable of synchroniz... Rhythmic oscillatory patterns sustain cellular dynamics, driving the concerted action of regulatory molecules, microtubules, and molecular motors. We describe cellular microtubules as oscillators capable of synchronization and swarming, generating mechanical and electric patterns that impact biomolecular recognition. We consider the biological relevance of seeing the inside of cells populated by a network of molecules that behave as bioelectronic circuits and chromophores. We discuss the novel perspectives disclosed by mechanobiology, bioelectromagnetism, and photobiomodulation, both in term of fundamental basic science and in light of the biomedical implication of using physical energies to govern (stem) cell fate. We focus on the feasibility of exploiting atomic force microscopy and hyperspectral imaging to detect signatures of nanomotions and electromagnetic radiation (light), respectively, generated by the stem cells across the specification of their multilineage repertoire. The chance is reported of using these signatures and the diffusive features of physical waves to direct specifically the differentiation program of stem cells in situ, where they already are resident in all the tissues of the human body. We discuss how this strategy may pave the way to a regenerative and precision medicine without the needs for (stem) cell or tissue transplantation. We describe a novel paradigm based upon boosting our inherent ability for self-healing. 展开更多
关键词 Stem cells PHYSICAL ENERGIES Mechanical forces Electric FIELDS ELECTROMAGNETIC FIELDS ELECTROMAGNETIC radiation PHOTOBIOMODULATION Damaged TISSUES
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Comparison of Collocation of Solar Concentrators with Bean Fields in Mexico and Potato Fields in Canada and Micromechanical Equipment for Their Production 预览
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作者 E.Kussul T.Baydyk +1 位作者 O.Olvera-Tapia J.Rodríguez Andrade 《能源与动力工程:英文版》 2019年第1期24-31,共8页
There is an increased interest in renewable forms of energy across the world,with solar energy being one of the most promising forms.Over the last couple of years,we have developed the MET(MicroEquipment Technology).A... There is an increased interest in renewable forms of energy across the world,with solar energy being one of the most promising forms.Over the last couple of years,we have developed the MET(MicroEquipment Technology).As an application of the MET,we selected the task of production of solar concentrators.Different types of solar concentrators with flat mirrors were developed and prototypes of these solar concentrators(approximately 1 m in diameter)were made.The proposed solar concentrators were developed on the basis of concentrators patented in Mexico,Spain,and USA.It may be possible to install these concentrators on horizontal roofs of buildings.However,installing them on agricultural fields has become the new trend.As an example,we propose to use them in the potato fields in Canada to obtain dual advantages such as for electrical energy generation and for the minimal loss of agricultural harvest.The second example was analyzed for bean fields,in Mexico.In this paper,we describe the main results in regard to microequipment development for solar concentrator production,several prototypes of solar concentrators with flat mirrors and their co-location and agricultural fields. 展开更多
关键词 MET microcomponents solar CONCENTRATORS flat mirrors BEAN FIELDS POTATO FIELDS
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Polarised radio emission associated with HESS J1912+101
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作者 Wolfgang Reich Xiao-Hui Sun 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2019年第3期123-130,共8页
The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant,but is missing counterparts at radio and other frequencies.We analysed the Sino-German Urumqiλ6 cm survey and the Effels... The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant,but is missing counterparts at radio and other frequencies.We analysed the Sino-German Urumqiλ6 cm survey and the Effelsberg λ11 cm and λ21 cm surveys to identify radio emission from HESS J1912+101 to clarify the question of a supernova origin.We find a partial shell of excessive polarisation at λ6 cm at the periphery of HESS J1912+101.At λ11 cm,its polarised emission is faint and suffers from depolarisation,while at λ21 cm,no related polarisation is seen.We could not separate the shell’s total intensity signal from the confusing intense diffuse emission from the inner Galactic plane.However,a high percentage of polarisation in the shell’s synchrotron emission is indicated.Our results support earlier suggestions that HESS J1912+101 is an old supernova remnant.The synchrotron emission is highly polarised,which is typical for evolved supernova remnants with low surface brightness. 展开更多
关键词 radio CONTINUUM ISM-ISM INDIVIDUAL OBJECTS HESS J1912+101-ISM magnetic FIELDS
游戏仪式与文化象征——以民间儿童游戏跳皮筋为例
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作者 李翠含 吕韶钧 《北京体育大学学报》 CSSCI 北大核心 2019年第3期139-148,共10页
跳皮筋作为一项民间儿童游戏,有着广泛的群众基础和丰富的文化内涵。为探讨儿童游戏跳皮筋的游戏过程和文化象征意义,采用文献资料法、田野调查法、访谈法等研究方法,对跳皮筋的游戏仪式和歌谣的文化内涵进行深入研究。研究认为,跳皮筋... 跳皮筋作为一项民间儿童游戏,有着广泛的群众基础和丰富的文化内涵。为探讨儿童游戏跳皮筋的游戏过程和文化象征意义,采用文献资料法、田野调查法、访谈法等研究方法,对跳皮筋的游戏仪式和歌谣的文化内涵进行深入研究。研究认为,跳皮筋可以看作一种游戏仪式,根据游戏的时序划分为开始仪式、过程仪式、结束仪式,各时序阶段都有不同的阈限规定;游戏仪式有特定的场域,在游戏的语境中表达自由和规则并存的游戏精神;跳皮筋歌谣是民众文化的重要载体,承载着民族情感和儿童行为模式的文化信息,记录着不同历史背景下的社会生活和时代风貌,其文化象征主要表现在叙事性与文化隐喻,生活性与文化体验,教育性与文化传承等。得出结论,儿童游戏跳皮筋是一种游戏仪式,具有深刻的文化象征含义。由此,在新时代背景下,可以充分发挥跳皮筋游戏的文化传承和教育价值,为全民健身和新时代体育强国建设做出贡献。 展开更多
关键词 跳皮筋 游戏仪式 歌谣 场域 象征 文化隐喻
Promotional effects of exogenous stimulation with pulsed electromagnetic fields on skin wound healing in diabetic rats
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作者 Yan Han Ze-Dong Yan Shu-Hua Ge 《海南医科大学学报(英文版)》 2019年第5期1-5,共5页
Objective:The current study aims to identify the effects of exogenous application of pulsed electromagnetic fields on skin wound healing in diabetic rats, and thus provides experimental evidence for its more scientifi... Objective:The current study aims to identify the effects of exogenous application of pulsed electromagnetic fields on skin wound healing in diabetic rats, and thus provides experimental evidence for its more scientific clinical application in the future.Methods: The diabetic animal models were established via intraperitoneal injection of streptozotocin in 4-month-old male rats. Fourth eight rats were randomly assigned into the diabetes group (DM) and diabetes coupled with pulsed electromagnetic fields (DM+PEMF) group. Another 24 normal rats were used as the blank control group (Control). Then, all the rats in the three groups were subjected to dorsal surgery for the establishment of soft tissue wound model (circular wound with the diameter of 2 cm). Then, the rats in the DM+PEMF group were subjected to pulsed electromagnetic fields stimulation. Then, 6 rats in each group were sacrificed at Day 5, 12 and 19 post surgery. The glucose levels, wound closure, wound healing time and tissue tensile strength were examined and analyzed.Results: Pulsed electromagnetic fields significantly increased the wound closure rate in diabetic rats at Day 5, 12 and 19 post surgery, decreased overall wound healing period in diabetic rats, and also enhanced tissue tensile strength in diabetic rats at Day 5, 12 and 19 post surgery.Conclusion: Low-intensity pulsed electromagnetic fields can significantly accelerate diabetic wound healing process, and also improve diabetic tissue repair capacity. This study may be helpful for providing more scientific and reasonable experimental evidence for the treatment of pulsed electromagnetic fields on diabetic wound healing in clinics. 展开更多
关键词 PULSED electromagnetic FIELDS Diabetes Sskin WOUND Tissue tensile strength GLUCOSE
Controllability analysis of multi-agent systems with switching topology over finite fields
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作者 Zehuan LU Lin ZHANG Long WANG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第1期77-91,共15页
In this paper,we investigate the controllability problem of multi-agent systems with switching topology over finite fields.The multi-agent system is defined over finite fields,where agents process only values from a f... In this paper,we investigate the controllability problem of multi-agent systems with switching topology over finite fields.The multi-agent system is defined over finite fields,where agents process only values from a finite alphabet.Under leader-follower structure,one agent is selected as a leader for each subsystem.First,we prove that a multi-agent system with switching topology is controllable over a finite field if the graph of the subsystem is a spanning forest,and the size of the field is sufficiently large.Second,we show that,by appropriately selecting leaders,the multi-agent system with switching topology can be controllable over a finite field even if each of its subsystems is not controllable.Specifically,we show that the number of leaders for ensuring controllability of the switched multi-agent system is less than the minimum number of leaders for ensuring the controllability of all subsystems.Finally,it is proved that the multi-agent system is controllable over a finite field if the union of the graphs is a directed path graph or a star graph. 展开更多
关键词 MULTI-AGENT systems LEADER-FOLLOWER structure CONTROLLABILITY finite FIELDS switching TOPOLOGY
Efficient solver for time-dependent Schrodinger equation with interaction between atoms and strong laser field
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作者 周胜鹏 刘爱华 +2 位作者 刘芳 王春成 丁大军 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第8期66-72,共7页
We present a parallel numerical method of simulating the interaction of atoms with a strong laser field by solving the time-depending Schrodinger equation(TDSE)in spherical coordinates.This method is realized by combi... We present a parallel numerical method of simulating the interaction of atoms with a strong laser field by solving the time-depending Schrodinger equation(TDSE)in spherical coordinates.This method is realized by combining constructing block diagonal matrices through using the real space product formula(RSPF)with splitting out diagonal sub-matrices for short iterative Lanczos(SIL)propagator.The numerical implementation of the solver guarantees efficient parallel computing for the simulation of real physical problems such as high harmonic generation(HHG)in these interaction systems. 展开更多
关键词 TIME-DEPENDENT SCHRODINGER equation STRONG laser FIELDS Parallel numerical SOLVER
Angle-resolved spectra of the direct above-threshold ionization of diatomic molecule in IR + XUV laser fields
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作者 石尚 金发成 王兵兵 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第2期185-191,共7页
The direct above-threshold ionization(ATI) of diatomic molecules in linearly-polarized infrared and extreme ultraviolet(IR+XUV) laser fields is investigated by the frequency–domain theory based on the nonperturbative... The direct above-threshold ionization(ATI) of diatomic molecules in linearly-polarized infrared and extreme ultraviolet(IR+XUV) laser fields is investigated by the frequency–domain theory based on the nonperturbative quantum electrodynamics. The destructive interference fringes on the angle-resolved ATI spectra, which are closely related to the molecular structure, can be well fitted by a simple predictive formula for any alignment of the molecular axis. By comparing the direct ATI spectra for monochromatic and two-color laser fields, we found that the XUV laser field can both raise the ionization probability and the kinetic energy of the ionized electron, while the infrared(IR) laser field can broaden the energy distribution of the ionized electron. Our results demonstrate that, by using IR+XUV two-color laser fields, the angle-resolved spectra of the direct ATI can image the structural information of molecules without considering the recollision process of the ionized electron. 展开更多
关键词 ABOVE-THRESHOLD IONIZATION IR+XUV laser FIELDS molecular structure
Chiral phase structure of the sixteen meson states in the SU(3) Polyakov linear-sigma model for finite temperature and chemical potential in a strong magnetic field
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作者 Abdel Nasser Tawfik Abdel Magied Diab M.T.Hussein 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期56-71,共16页
In characterizing the chiral phase-structure of pseudoscalar(Jpc = 0-+), scalar(Jpc = 0++), vector(Jpc =1--) and axial-vector(Jpc = 1++t) meson states and their dependence on temperature, chemical potential, and magne... In characterizing the chiral phase-structure of pseudoscalar(Jpc = 0-+), scalar(Jpc = 0++), vector(Jpc =1--) and axial-vector(Jpc = 1++t) meson states and their dependence on temperature, chemical potential, and magnetic field,we utilize the SU(3) Polyakov linear-sigma model(PLSM) in the mean-field approximation. We first determine the chiral(non)strange quark condensates,σl and σs, and the corresponding deconfinement order parameters, φ and φ*, in thermal and dense(finite chemical potential) medium and finite magnetic field. The temperature and the chemical potential characteristics of nonet meson states normalized to the lowest bosonic Matsubara frequency are analyzed. We note that all normalized meson masses become temperature independent at different critical temperatures. We observe that the chiral and deconfinement phase transitions are shifted to lower quasicritical temperatures with increasing chemical potential and magnetic field. Thus, we conclude that the magnetic field seems to have almost the same effect as the chemical potential, especially on accelerating the phase transition, i.e. inverse magnetic catalysis. We also find that increasing the chemical potential enhances the mass degeneracy of the various meson masses, while increasing the magnetic field seems to reduce the critical chemical potential, at which the chiral phase transition takes place. Our mass spectrum calculations agree well with the recent PDG compilations and PNJL, lattice QCD calculations, and QMD/UrQMD simulations. 展开更多
关键词 CHIRAL transition MAGNETIC fields MAGNETIC catalysis critical temperature viscous properties of QGP
规范场中Skyrme模型单位拓扑电荷的双荷子 预览
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作者 吴忠林 李东亚 《数学季刊:英文版》 2019年第2期152-170,共19页
Dyons are an important family of topological solitons carrying both electric and magnetic charges and the presence of a nontrivial temporal component of the gauge field essential for the existence of electricity often... Dyons are an important family of topological solitons carrying both electric and magnetic charges and the presence of a nontrivial temporal component of the gauge field essential for the existence of electricity often makes the analysis of the underlying nonlinear equations rather challenging since the governing action functional assumes an indefinite form.In this work,developing a constrained variational technique,We establish an existence theorem for the dyon solitons in a Skyrme model coupled with SO(3)-gauge fields,formulated by Brihaye,Kleihaus,and Tchrakian.These solutions carry unit monopole and Skyrme charges. 展开更多
关键词 SKYRME model gauge fields DYONS calculus of variations for INDEFINITE action FUNCTIONALS weak convergence
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Fields of Hope
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作者 Wang Hairong 《北京周报:英文版》 2019年第9期34-35,共2页
New technology,profit-sharing incentive schemes and business models contribute to rural poverty alleviation Tucked in the mountains in southwest Beijing,Lijia Village in Qingshui Town of Mentougou District was a relat... New technology,profit-sharing incentive schemes and business models contribute to rural poverty alleviation Tucked in the mountains in southwest Beijing,Lijia Village in Qingshui Town of Mentougou District was a relatively poor area of the capital.But in recent years,its fate has been changed by a miniature fruit called kiwiberry. 展开更多
关键词 In FIELDS of HOPE
Distribution and exploration direction of medium-and large-sized marine carbonate gas fields in Sichuan Basin, SW China 预览
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作者 MA Xinhua YANG Yu +1 位作者 WEN Long LUO Bing 《石油勘探与开发:英文版》 2019年第1期1-15,共15页
Based on the analysis of the basic characteristics of medium-and large-sized marine gas fields in Sichuan Basin,combined with the division of major reservoir forming geological units in the marine craton stage and the... Based on the analysis of the basic characteristics of medium-and large-sized marine gas fields in Sichuan Basin,combined with the division of major reservoir forming geological units in the marine craton stage and their control on key hydrocarbon accumulation factors,the distribution law of medium-and large-sized marine carbonate gas fields in the basin was examined and the exploration direction was pointed out.Through the analysis of the periodic stretching-uplifting background,it is concluded that five large scale paleo-rifts,three large scale paleo-uplifts,five large scale paleo erosion surfaces were formed in the marine craton stage of Sichuan Basin,and these geological units control the key reservoir forming factors of medium and large sized gas fields:(1)Large-scale paleo-rifts control the distribution of high-quality hydrocarbon generation centers.(2)The margin of large-scale paleo-rifts,high position of paleo-uplifts and paleo erosion surfaces control the distribution of high-quality reservoirs.(3)Large-scale paleo-rifts,paleo-uplifts,paleo erosion surfaces and present tectonic setting jointly control the formation of many types of large and medium-sized traps.(4)Natural gas accumulation is controlled by the inheritance evolution of traps in large geological units.Based on the comparative analysis of the distribution characteristics of medium-and large-sized gas fields and large geological units,it is proposed that the superimposition relationship between single or multiple geological units and the present structure controls the distribution of medium-and large-sized gas fields,and the'three paleo'superimposed area is the most advantageous.According to the above rules,the main exploration fields and directions of medium-and large-sized marine carbonate gas fields in Sichuan Basin include periphery of Deyang-Anyue paleo-rift,eastern margin of Longmenshan paleo-rift,margins of Kaijiang-Liangping oceanic trough and Chengkou-western Hubei oceanic trough,the high part of the subaqueous paleo-uplifts around Cen 展开更多
关键词 Sichuan Basin marine CARBONATES medium-and large-sized gas fields GEOLOGIC unit reservoir forming factors paleo-rifts paleo-uplifts paleo erosion surfaces
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On the possibility of disk-fed formation in supergiant high-mass X-ray binaries
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作者 Ali Taani Shigeyuki Karino +3 位作者 Liming Song Mashhoor Al-Wardat Awni Khasawneh Mohammad K.Mardini 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2019年第1期123-130,共8页
We consider the existence of a neutron star magnetic field by the detected cyclotron lines. We collected data on nine sources of high-mass X-ray binaries with supergiant companions as a test case for our model, to dem... We consider the existence of a neutron star magnetic field by the detected cyclotron lines. We collected data on nine sources of high-mass X-ray binaries with supergiant companions as a test case for our model, to demonstrate their distribution and evolution. The wind velocity, spin period and magnetic field strength are studied under different mass loss rates. In our model, correlations between mass-loss rate and wind velocity are found and can be tested in further observations. We examine the parameter space where wind accretion is allowed, avoiding the barrier of rotating magnetic fields, with robust data on the magnetic field of neutron stars. Our model shows that most sources(six of nine systems) can be fed by the wind with relatively slow velocity, and this result is consistent with previous predictions. In a few sources,our model cannot fit the standard wind accretion scenario. In these peculiar cases, other scenarios(disk formation, partial Roche lobe overflow) should be considered. This would provide information about the evolutionary tracks of various types of binaries, and thus exhibit a clear dichotomy behavior in wind-fed X-ray binary systems. 展开更多
关键词 binaries:X-rays stars:neutron stars:fundamental parameters ACCRETION DISKS FORMATION magnetic fields
Tunable protein microlens array
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作者 侯智善 曹嘉冀 +1 位作者 李爱武 杨罕 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第6期65-68,共4页
Based on natural protein materials,a series of lenses with different heights and focal lengths were assembled on glass substrates by femtosecond laser non-contact,masking,and cold processing.This lens array itself pos... Based on natural protein materials,a series of lenses with different heights and focal lengths were assembled on glass substrates by femtosecond laser non-contact,masking,and cold processing.This lens array itself possesses unique and characteristic optical performance in three-dimensional parallel imaging and bending imaging.What is more profound is that by using equilibrium swelling of protein-hydrogel,once the lens array was placed in a liquid environment,with the change of ion concentration(e.g.,pH),the refractive index and curvature of the protein-hydrogel would change,which leads to the flex of the focal plane of the lens,finally realizing the dynamical tunability of a protein microlens.These smart stress devices may have great potential in optical biosensing and microfluidic chip integration fields. 展开更多
关键词 Based on NATURAL PROTEIN materials different HEIGHTS CHIP integration FIELDS
A Construction of Multi-Sender Authentication Codes from Eigenvalues and Eigenvectors of the Matrix Over Finite Fields 预览
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作者 Xiuli Wang Lina Wang Yakun Hao 《哈尔滨工业大学学报:英文版》 EI CAS 2019年第1期51-60,共10页
We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful atta... We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful attack of this code are also computed. For multi-sender authentication code, it allows a group of senders to construct an authenticated message for a receiver such that the receiver can verify authenticity of the received message. 展开更多
关键词 multi-sender AUTHENTICATION codes NONSINGULAR symmetric matrix EIGENVALUES EIGENVECTORS finite fields
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Heavy fermions in high magnetic fields
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作者 M Smidman 沈斌 +3 位作者 郭春煜 焦琳 路欣 袁辉球 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期25-38,共14页
Heavy fermion materials are prototypical strongly correlated electron systems, where the strong electron–electron interactions lead to a wide range of novel phenomena and emergent phases of matter. Due to the low ene... Heavy fermion materials are prototypical strongly correlated electron systems, where the strong electron–electron interactions lead to a wide range of novel phenomena and emergent phases of matter. Due to the low energy scales, the relative strengths of the Ruderman–Kittel–Kasuya–Yosida(RKKY) and Kondo interactions can often be readily tuned by non-thermal control parameters such as pressure, doping, or applied magnetic fields, which can give rise to quantum criticality and unconventional superconductivity. Here we provide a brief overview of research into heavy fermion materials in high magnetic fields, focussing on three main areas. Firstly we review the use of magnetic fields as a tuning parameter,and in particular the ability to realize different varieties of quantum critical behaviors. We then discuss the properties of heavy fermion superconductors in magnetic fields, where experiments in applied fields can reveal the nature of the order parameter, and induce new novel phenomena. Finally we report recent studies of topological Kondo systems, including topological Kondo insulators and Kondo–Weyl semimetals. Here experiments in magnetic fields can be used to probe the topologically non-trivial Fermi surface, as well as related field-induced phenomena such as the chiral anomaly and topological Hall effect. 展开更多
关键词 HEAVY FERMIONS high magnetic fields quantum phase TRANSITIONS HEAVY FERMION SUPERCONDUCTIVITY topological KONDO systems
Quantum anomalous Hall heterostructures
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作者 Ke He Qi-Kun Xue 《国家科学评论:英文版》 CSCD 2019年第2期202-204,共3页
The discoveries of the integer and fractional quantum Hall effects in the early 1980s unveiled an exotic world of topological quantum matter [1]. This fascinating world, however, remains largely Platonic in the sense ... The discoveries of the integer and fractional quantum Hall effects in the early 1980s unveiled an exotic world of topological quantum matter [1]. This fascinating world, however, remains largely Platonic in the sense that most of the predicted topological quantum phases are still far away from experimental realization. For a time, almost the only way to find a new topological quantum phase was to search for quantum Hall systems w让 h higher carrier mobil让ies at lower temperatures and under stronger magnetic fields. 展开更多
关键词 discoveries HALL FIELDS
Problems of Lifts in Symplectic Geometry
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作者 Arif SALIMOV Manouchehr BEHBOUDI ASL Sevil KAZIMOVA 《数学年刊:B辑英文版》 SCIE CSCD 2019年第3期321-330,共10页
Let(M,ω)be a symplectic manifold.In this paper,the authors consider the notions of musical(bemolle and diesis)isomorphisms ωb:T M→T*M and ω?:T*M→TM between tangent and cotangent bundles.The authors prove that the... Let(M,ω)be a symplectic manifold.In this paper,the authors consider the notions of musical(bemolle and diesis)isomorphisms ωb:T M→T*M and ω?:T*M→TM between tangent and cotangent bundles.The authors prove that the complete lifts of symplectic vector field to tangent and cotangent bundles is ωb-related.As consequence of analyze of connections between the complete lift cωT M of symplectic 2-form ω to tangent bundle and the natural symplectic 2-form dp on cotangent bundle,the authors proved that dp is a pullback o fcωTMby ω?.Also,the authors investigate the complete lift cφT*M )of almost complex structure φ to cotangent bundle and prove that it is a transform by ω?of complete liftcφT M to tangent bundle if the triple(M,ω,φ)is an almost holomorphic A-manifold.The transform of complete lifts of vector-valued 2-form is also studied. 展开更多
关键词 Symplectic MANIFOLD TANGENT BUNDLE Cotangent BUNDLE Transform of TENSOR fields PULLBACK Pure TENSOR HOLOMORPHIC MANIFOLD
Magnetization dynamics and related phenomena in semiconductors with ferromagnetism 预览
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作者 Lin Chen Jianhua Zhao +3 位作者 Dieter Weiss Christian H. Back Fumihiro Matsukura Hideo Ohno 《半导体学报:英文版》 EI CAS CSCD 2019年第8期20-27,共8页
We review ferromagnetic resonance (FMR) and related phenomena in the ferromagnetic semiconductor (Ga,Mn)As and single crystalline Fe/GaAs (001) hybrid structures. In both systems, spin-orbit interaction is the key ing... We review ferromagnetic resonance (FMR) and related phenomena in the ferromagnetic semiconductor (Ga,Mn)As and single crystalline Fe/GaAs (001) hybrid structures. In both systems, spin-orbit interaction is the key ingredient for various intriguing phenomena. 展开更多
关键词 (Ga Mn)As Fe/GaAs FERROMAGNETIC resonance Gilbert damping ELECTRIC-FIELD effect on MAGNETISM SPIN-ORBIT fields
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Sensing of ultrasonic fields based on polarization parametric indirect microscopic imaging
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作者 曹云 熊吉川 +4 位作者 刘学峰 夏志颖 王惟泽 N.P.Yadav 刘卫平 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第4期89-94,共6页
This Letter tackles the issue of non-contact detection of ultrasonic fields by utilizing a novel optical method based on the parametric indirect microscopic imaging(PIMI) technique. A general theoretical model describ... This Letter tackles the issue of non-contact detection of ultrasonic fields by utilizing a novel optical method based on the parametric indirect microscopic imaging(PIMI) technique. A general theoretical model describing the three-dimensional anisotropic photoelastic effect in solid was developed. The mechanism of polarization status variations of light passing through the stress and strain fields was analyzed. Non-contact measurements of the ultrasonic field propagating in an isotropic quartz glass have been fulfilled by the PIMI technique under different ultrasonic excitation conditions. PIMI parameters such as sin δ,Φ, and the Stokes parameters have been found to be sensitive to ultrasonic fields. 展开更多
关键词 LETTER tackles detection of ULTRASONIC ULTRASONIC FIELDS
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