In this paper we address the dynamics of compensation cutting process from both Laplace s frequency domain and the time domain of the first time, using the two computer aided analyzing softwares: MATLAB and SIMULI...In this paper we address the dynamics of compensation cutting process from both Laplace s frequency domain and the time domain of the first time, using the two computer aided analyzing softwares: MATLAB and SIMULINK. Theoretical analysis and simulation experiments firstly show that not only the systematical stiffness of workpiece, spindle and tools, but also the regenerated coefficient affects the compensation displacement effect. The results show that the SREC is practicable in reality to decease the spindle induced errors in many engineering applications such as hard boring through simulation and the preliminary experiment results.展开更多
The optical rotation technique arose in the 1990 s.Optical tweezer brought an ideal platform for research on the angular momentum of laser beams.For decades,the optical rotation technique has been widely applied in la...The optical rotation technique arose in the 1990 s.Optical tweezer brought an ideal platform for research on the angular momentum of laser beams.For decades,the optical rotation technique has been widely applied in laboratory optical manipulation and the fields of biology and optofluidics.Recently,it has attracted much attention for its potential in the classical and quantum regimes.In this work,we review the progress of experiments and applications of optically induced rotation.First,we introduce the basic exploration of angular momentum.Then,we cover the development and application of optical rotation induced by orbital angular momentum,and the spin angular momentum is presented.Finally,we elaborate on recent applications of the optical rotation technique in high vacuum.As precise optical manipulation in a liquid medium enters its maturity,optical tweezers in high vacuum open a new path for the high-speed micro-rotor.展开更多
The poloidal rotation of the magnetized edge plasma in tokamak driven by the ponderomotive force which is generated by injecting lower hybrid wave(LHW) electric field has been studied. The LHW is launched from a waveg...The poloidal rotation of the magnetized edge plasma in tokamak driven by the ponderomotive force which is generated by injecting lower hybrid wave(LHW) electric field has been studied. The LHW is launched from a waveguide in the plasma edge, and by Brambilla's grill theory, analytic expressions for the wave electric field in the slab model of an inhomogeneous cold plasma have been derived. It is shown that a strong wave electric field will be generated in the plasma edge by injecting LH wave of the power in MW magnitude, and this electric field will induce a poloidal rotation with a sheared poloidal velocity.展开更多
The structural characteristics of the critically rotating accretor in binaries are investigated during rapid mass transfer. It is found that the accretor is subjected to periodic pulsation due to accretions and reject...The structural characteristics of the critically rotating accretor in binaries are investigated during rapid mass transfer. It is found that the accretor is subjected to periodic pulsation due to accretions and rejections of mass and angular momentum. Tile gainer attempts to attain both hydrostatic and thermal balances. This physical process can cause tile thermal structure of the accreting star to fluctuate with a period of ~ 0.19 y. Stellar wind can be enhanced by a factor of ~1.25 ×10^4 when the accretor approaches break-down velocity. Surface entropy and density decrease with the increase of the stellar radius due to the fact that rapid rotation leads to a reduction in the number density and surface temperature. The rotational energy has the same trend as stellar radius due to stellar expansion. Surface opacity which is extremely sensitive to surface temperature has an opposite trend to stellar radius. Moreover, the rate of nuclear energy must be adjusted due to mass removal or accretion at the stellar surface.展开更多
We experimentally demonstrate a mechanically tunable metamaterials terahertz(THz) dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high res...We experimentally demonstrate a mechanically tunable metamaterials terahertz(THz) dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high resistance silicon substrate. The performance of the filter is simulated by finite-integration-time-domain(FITD) method. The sample is fabricated using a surface micromachining process and experimentally demonstrated using a THz time-domain-spectroscopy(TDS) system. The results show that, when the incident THz wave is polarized in y-axis, the filter has two intensive absorption peaks locating at 0.71 THz and 1.13 THz, respectively. The position of the high-frequency absorption peak and the amplitude of the low-frequency absorption peak can be simultaneously tuned by rotating the sample along its normal axis.The tunability of the high-frequency absorption peak is due to the shift of resonance frequency of two electrical dipoles,and that of the low-frequency absorption peak results from the effect of rotationally induced transparent. This tunable filter is very useful for switch, manipulation, and frequency selective detection of THz beam.展开更多
We analyze in this work anisotropic heat conduction induced by a harmonically oscillating laser source incident on rotating conductors, exploiting an analogy with an effect discovered long ago, called the Zel’dovich ...We analyze in this work anisotropic heat conduction induced by a harmonically oscillating laser source incident on rotating conductors, exploiting an analogy with an effect discovered long ago, called the Zel’dovich effect. We re-covered the main results of a recently published paper that predicts the translational Doppler frequency shift of a thermal wave induced on a sample moving with uniform rectilinear motion. We extend then this framework to take into account the frequency shift of a thermal field propagating on a rotating platform. We show that it coincides with the rotational frequency shift which has been recently observed on surface acoustic waves and hydrodynamic surface waves, called rotational superradiance. Finally, we use an analogy with the Tolman effect to deduce a simple estimate of the average temperature gradient induced by rotation, showing the existence of a new cooling effect associated with heat torque transfer.展开更多
Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog...Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog to a liquid floated gyroscope with three degree-of-ffeedom.In this work,we analyzed the feasibility of applying optically levitated rotor in the system.We presented the dynamic analysis and simulation of an ellipsoid micron particle.The precession motion and nutation motion of a rotating ellipsoid probe particle in optical tweezers were performed.We also analyzed the attitude changes of an optically levitated ellipsoid when there was variation of the external torque caused by deviation of the incident light that was provided.Furthermore,the trail path of the rotational axis vertex and the stabilization process of a particle of different ellipticities were simulated.We compared the movement tendencies of particles of different shapes and analyzed the selection criteria of ellipsoid rotor.These analytical formulae and simulation results are applicable to the analysis of the rotational motion of particles in optical tweezers,especially to the future research of the gyroscope effect.展开更多
The study aimed to shed light on the post deformation and damage behavior of an extruded Mg-Zn-Zr alloy under a ballistic impact.The results revealed that the initial microstructure consisted of both{0001}basal and{10...The study aimed to shed light on the post deformation and damage behavior of an extruded Mg-Zn-Zr alloy under a ballistic impact.The results revealed that the initial microstructure consisted of both{0001}basal and{1010}prismatic fiber texture.After impact,adiabatic shear bands,pronounce different twinning in big grains,,<c>,and<c+a>types of dislocations,and grain refinement through twinning induce recrystallization accommodated the strain,and absorbed∼65.7%of the energy during impact carried by a soft steel projectile.Interestingly,the deformation behavior at the top broad sides of the crater was entirely different.The weak basal texture was changed to a strong prismatic texture,which was further proved by typical sigmoidal compressive stress-strain curves.A revised model for the development of the ultra-fine grains adjacent to the crater has been proposed.The microhardness and yield strength was∼33%and∼40%higher and chiefly ascribed to strain hardening in ultra-fine grained near the surface of the perforation path.The exit of the perforation path was severely damaged and forms onion-shaped concentric rings which were comprised of melted zones,dimples,and cracks.Based on the all interesting findings,this study can be a clue for the development of the lightweight Mg alloy for military and aerospace applications.展开更多
文摘In this paper we address the dynamics of compensation cutting process from both Laplace s frequency domain and the time domain of the first time, using the two computer aided analyzing softwares: MATLAB and SIMULINK. Theoretical analysis and simulation experiments firstly show that not only the systematical stiffness of workpiece, spindle and tools, but also the regenerated coefficient affects the compensation displacement effect. The results show that the SREC is practicable in reality to decease the spindle induced errors in many engineering applications such as hard boring through simulation and the preliminary experiment results.
基金supported by the National Natural Science Foundation of China(Nos.11304282 and 10947104)the National Program for Special Support of Top-Notch Young Professionals,China+1 种基金the Fundamental Research Fund for the Central Universities,China(No.2018XZZX001-08)the Major Scientific Research Project of Zhejiang Lab,China(No.2019MB0AD01)。
文摘The optical rotation technique arose in the 1990 s.Optical tweezer brought an ideal platform for research on the angular momentum of laser beams.For decades,the optical rotation technique has been widely applied in laboratory optical manipulation and the fields of biology and optofluidics.Recently,it has attracted much attention for its potential in the classical and quantum regimes.In this work,we review the progress of experiments and applications of optically induced rotation.First,we introduce the basic exploration of angular momentum.Then,we cover the development and application of optical rotation induced by orbital angular momentum,and the spin angular momentum is presented.Finally,we elaborate on recent applications of the optical rotation technique in high vacuum.As precise optical manipulation in a liquid medium enters its maturity,optical tweezers in high vacuum open a new path for the high-speed micro-rotor.
基金the Nuclear Science Foundation under Grant! No. H7196c0302.
文摘The poloidal rotation of the magnetized edge plasma in tokamak driven by the ponderomotive force which is generated by injecting lower hybrid wave(LHW) electric field has been studied. The LHW is launched from a waveguide in the plasma edge, and by Brambilla's grill theory, analytic expressions for the wave electric field in the slab model of an inhomogeneous cold plasma have been derived. It is shown that a strong wave electric field will be generated in the plasma edge by injecting LH wave of the power in MW magnitude, and this electric field will induce a poloidal rotation with a sheared poloidal velocity.
基金Supported by the National Natural Science Foundation of China under Grant No 11463002the Open Foundation of Key Laboratory for the Structure and Evolution of Celestial Objects of Chinese Academy of Sciences under Grant No OP201405the Western Project of State Scholarship Foundation by the China Scholarship Council
文摘The structural characteristics of the critically rotating accretor in binaries are investigated during rapid mass transfer. It is found that the accretor is subjected to periodic pulsation due to accretions and rejections of mass and angular momentum. Tile gainer attempts to attain both hydrostatic and thermal balances. This physical process can cause tile thermal structure of the accreting star to fluctuate with a period of ~ 0.19 y. Stellar wind can be enhanced by a factor of ~1.25 ×10^4 when the accretor approaches break-down velocity. Surface entropy and density decrease with the increase of the stellar radius due to the fact that rapid rotation leads to a reduction in the number density and surface temperature. The rotational energy has the same trend as stellar radius due to stellar expansion. Surface opacity which is extremely sensitive to surface temperature has an opposite trend to stellar radius. Moreover, the rate of nuclear energy must be adjusted due to mass removal or accretion at the stellar surface.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61265005 and 11574059)the Natural Science Foundation of Guangxi,China(Grant Nos.2015GXNSFDA19039 and 2014GXNSFAA118376)+1 种基金the Foundation from Guangxi Key Laboratory of Automatic Detection Technology and Instrument,China(Grant Nos.YQ14114 and YQ15106)the Innovation Project of Guangxi Graduate Education,China(Grant Nos.2016YJCX03 and2016YJCX31)
文摘We experimentally demonstrate a mechanically tunable metamaterials terahertz(THz) dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high resistance silicon substrate. The performance of the filter is simulated by finite-integration-time-domain(FITD) method. The sample is fabricated using a surface micromachining process and experimentally demonstrated using a THz time-domain-spectroscopy(TDS) system. The results show that, when the incident THz wave is polarized in y-axis, the filter has two intensive absorption peaks locating at 0.71 THz and 1.13 THz, respectively. The position of the high-frequency absorption peak and the amplitude of the low-frequency absorption peak can be simultaneously tuned by rotating the sample along its normal axis.The tunability of the high-frequency absorption peak is due to the shift of resonance frequency of two electrical dipoles,and that of the low-frequency absorption peak results from the effect of rotationally induced transparent. This tunable filter is very useful for switch, manipulation, and frequency selective detection of THz beam.
文摘We analyze in this work anisotropic heat conduction induced by a harmonically oscillating laser source incident on rotating conductors, exploiting an analogy with an effect discovered long ago, called the Zel’dovich effect. We re-covered the main results of a recently published paper that predicts the translational Doppler frequency shift of a thermal wave induced on a sample moving with uniform rectilinear motion. We extend then this framework to take into account the frequency shift of a thermal field propagating on a rotating platform. We show that it coincides with the rotational frequency shift which has been recently observed on surface acoustic waves and hydrodynamic surface waves, called rotational superradiance. Finally, we use an analogy with the Tolman effect to deduce a simple estimate of the average temperature gradient induced by rotation, showing the existence of a new cooling effect associated with heat torque transfer.
基金Our research is supported by Major Scientific Research Project of 378 Zhejiang Lab(Grant No.2019MB0AD01)National Program for Special Support of Top-Notch Young Professionals,Fundamental Research Funds for the Central Universities 380(Grant Nos.2016XZZX004-01 and 2018 XZZX001-08)。
文摘Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog to a liquid floated gyroscope with three degree-of-ffeedom.In this work,we analyzed the feasibility of applying optically levitated rotor in the system.We presented the dynamic analysis and simulation of an ellipsoid micron particle.The precession motion and nutation motion of a rotating ellipsoid probe particle in optical tweezers were performed.We also analyzed the attitude changes of an optically levitated ellipsoid when there was variation of the external torque caused by deviation of the incident light that was provided.Furthermore,the trail path of the rotational axis vertex and the stabilization process of a particle of different ellipticities were simulated.We compared the movement tendencies of particles of different shapes and analyzed the selection criteria of ellipsoid rotor.These analytical formulae and simulation results are applicable to the analysis of the rotational motion of particles in optical tweezers,especially to the future research of the gyroscope effect.
基金This project was financially supported by the National Natural Science Foundation of China(No.51702015)。
文摘The study aimed to shed light on the post deformation and damage behavior of an extruded Mg-Zn-Zr alloy under a ballistic impact.The results revealed that the initial microstructure consisted of both{0001}basal and{1010}prismatic fiber texture.After impact,adiabatic shear bands,pronounce different twinning in big grains,,<c>,and<c+a>types of dislocations,and grain refinement through twinning induce recrystallization accommodated the strain,and absorbed∼65.7%of the energy during impact carried by a soft steel projectile.Interestingly,the deformation behavior at the top broad sides of the crater was entirely different.The weak basal texture was changed to a strong prismatic texture,which was further proved by typical sigmoidal compressive stress-strain curves.A revised model for the development of the ultra-fine grains adjacent to the crater has been proposed.The microhardness and yield strength was∼33%and∼40%higher and chiefly ascribed to strain hardening in ultra-fine grained near the surface of the perforation path.The exit of the perforation path was severely damaged and forms onion-shaped concentric rings which were comprised of melted zones,dimples,and cracks.Based on the all interesting findings,this study can be a clue for the development of the lightweight Mg alloy for military and aerospace applications.