The phase and frequency locking of microwave, millimeter wave power combining were analysed and summarized in an all-round way. The master/slave phase locking of cavity oscillators, the peer phase locking of mutually ...The phase and frequency locking of microwave, millimeter wave power combining were analysed and summarized in an all-round way. The master/slave phase locking of cavity oscillators, the peer phase locking of mutually coupled oscillators, and the peer phase locking of ring-connected multiple oscillators were investigated. The results of numerical calculations, and the relations of phase to phase locking model and oscillator parameters were given. And the cavity and space power combining aspects for microwave and millimeter wave were presented.展开更多
Recently, spin-momentum-locked topological surface states(SSs) have attracted significant attention in spintronics.Owing to spin-momentum locking, the direction of the spin is locked at right angles with respect to ...Recently, spin-momentum-locked topological surface states(SSs) have attracted significant attention in spintronics.Owing to spin-momentum locking, the direction of the spin is locked at right angles with respect to the carrier momentum.In this paper, we briefly review the exotic transport properties induced by topological SSs in topological-insulator(TI)nanostructures, which have larger surface-to-volume ratios than those of bulk TI materials. We discuss the electrical spin generation in TIs and its effect on the transport properties. A current flow can generate a pure in-plane spin polarization on the surface, leading to a current-direction-dependent magnetoresistance in spin valve devices based on TI nanostructures.A relative momentum shift of two coupled topological SSs also generates net spin polarization and induces an in-plane anisotropic negative magnetoresistance. Therefore, the spin-momentum locking can enable the broad tuning of the spin transport properties of topological devices for spintronic applications.展开更多
This paper proposes a novel clamping device for leveling equipment mounted on offshore oil platform jacket,which solves the problem of leveling equipment clamping lifting force of more than 2000 tons.The main features...This paper proposes a novel clamping device for leveling equipment mounted on offshore oil platform jacket,which solves the problem of leveling equipment clamping lifting force of more than 2000 tons.The main features are that lifting force transmits to clamp claw through wedge force amplifier,embed the teeth of claw into the pile,and the embedded depth increases with the lifting force,resulting in a gravitational self-locking function.This theoretical model of clamping device was established,and the force and material characteristic were analyzed,and the feasibility of the theoretical model was verified by thin shell elastic-plastic stability theory and thin-walled structures theory.An experimental prototype of clamping device was produced to test gravity self-locking function and bearable leveling force.Compared with the theoretical model and the experimental results,it proved that the embedded clamping devices have gravitational self-locking function and can meet the need of actual leveling equipment.展开更多
The equivalent circuit of single-cavity multiple-device fundamentaloscillator(SCMDFO)and that of single-device harmonic oscillator(SDHO)proposed byK.Kurokawa and K.Solbach,respectively,are extended and applied to a si...The equivalent circuit of single-cavity multiple-device fundamentaloscillator(SCMDFO)and that of single-device harmonic oscillator(SDHO)proposed byK.Kurokawa and K.Solbach,respectively,are extended and applied to a single-cavitymultiple-device harmonic oscillator(SCMDHO).By means of describing the functions ofnonlinearity of Gunn diodes,the performances of the SCMDHO are analyzed.It is foundthat the voltage amplitudes are similar to those of SDHO,and the ratio of maximum pow-er of harmonic to that of fundamental is identical to that in SDHO when the devices havesame parameters.The harmonic injection locking behavior is also investigated.The injec-tion locking range is greater than that of SDHO if locking gain remains constant.A2-Gunn diode harmonic oscillator was designed.It delivers 30mW output power at103GHz.The mechanical tuning range is 4.15GHz when the output power remains morethan 10mW.The desired operation mode is stable.展开更多
基金Supported by the National Natural Science Foundation of China
文摘The phase and frequency locking of microwave, millimeter wave power combining were analysed and summarized in an all-round way. The master/slave phase locking of cavity oscillators, the peer phase locking of mutually coupled oscillators, and the peer phase locking of ring-connected multiple oscillators were investigated. The results of numerical calculations, and the relations of phase to phase locking model and oscillator parameters were given. And the cavity and space power combining aspects for microwave and millimeter wave were presented.
基金Project supported by the National Key Basic Research Program of China(Grant Nos.2014CB921103 and 2017YFA0206304)the National Natural Science Foundation of China(Grant Nos.61822403,11874203,U1732159,and U1732273)+1 种基金Fundamental Research Funds for the Central Universities,China(Grant No.021014380080)Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics,China
文摘Recently, spin-momentum-locked topological surface states(SSs) have attracted significant attention in spintronics.Owing to spin-momentum locking, the direction of the spin is locked at right angles with respect to the carrier momentum.In this paper, we briefly review the exotic transport properties induced by topological SSs in topological-insulator(TI)nanostructures, which have larger surface-to-volume ratios than those of bulk TI materials. We discuss the electrical spin generation in TIs and its effect on the transport properties. A current flow can generate a pure in-plane spin polarization on the surface, leading to a current-direction-dependent magnetoresistance in spin valve devices based on TI nanostructures.A relative momentum shift of two coupled topological SSs also generates net spin polarization and induces an in-plane anisotropic negative magnetoresistance. Therefore, the spin-momentum locking can enable the broad tuning of the spin transport properties of topological devices for spintronic applications.
文摘This paper proposes a novel clamping device for leveling equipment mounted on offshore oil platform jacket,which solves the problem of leveling equipment clamping lifting force of more than 2000 tons.The main features are that lifting force transmits to clamp claw through wedge force amplifier,embed the teeth of claw into the pile,and the embedded depth increases with the lifting force,resulting in a gravitational self-locking function.This theoretical model of clamping device was established,and the force and material characteristic were analyzed,and the feasibility of the theoretical model was verified by thin shell elastic-plastic stability theory and thin-walled structures theory.An experimental prototype of clamping device was produced to test gravity self-locking function and bearable leveling force.Compared with the theoretical model and the experimental results,it proved that the embedded clamping devices have gravitational self-locking function and can meet the need of actual leveling equipment.
基金The Project Supported by National Science Foundation of China
文摘The equivalent circuit of single-cavity multiple-device fundamentaloscillator(SCMDFO)and that of single-device harmonic oscillator(SDHO)proposed byK.Kurokawa and K.Solbach,respectively,are extended and applied to a single-cavitymultiple-device harmonic oscillator(SCMDHO).By means of describing the functions ofnonlinearity of Gunn diodes,the performances of the SCMDHO are analyzed.It is foundthat the voltage amplitudes are similar to those of SDHO,and the ratio of maximum pow-er of harmonic to that of fundamental is identical to that in SDHO when the devices havesame parameters.The harmonic injection locking behavior is also investigated.The injec-tion locking range is greater than that of SDHO if locking gain remains constant.A2-Gunn diode harmonic oscillator was designed.It delivers 30mW output power at103GHz.The mechanical tuning range is 4.15GHz when the output power remains morethan 10mW.The desired operation mode is stable.