The statics characteristics of two coupled Bose-Einstein condensate (BEC) dark solitons trapped in an optical lattice are investigated with the variational approach.It is found that the interaction between a ‘kink’ ...The statics characteristics of two coupled Bose-Einstein condensate (BEC) dark solitons trapped in an optical lattice are investigated with the variational approach.It is found that the interaction between a ‘kink’ and an ‘anti-kink’ with opposite phase gradients is effectively repulsive, and the optical lattice can be controllably used to produce a pair of static BEC dark solitons.Its effect depends on the initial location of the BEC dark solitons, the lattice amplitude and wave number.展开更多
Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method...Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method, we successfully obtain periodic wave solutions and solitary wave solutions, including the bright and dark soliton solutions.The results in this paper include some in the literatures [Phys. Rev. Lett. 94 （2005） 050402 and Chin. Phys. Left. 22 （2005） 1855].展开更多
We present a systematic study on the formation of ultra-slow bright and dark optical solitons in highly resonant media. By investigating four life-time broadened atomic systems, i.e., three-state A-type and cascade-ty...We present a systematic study on the formation of ultra-slow bright and dark optical solitons in highly resonant media. By investigating four life-time broadened atomic systems, i.e., three-state A-type and cascade-type schemes, and four-state N-type and cascade-type schemes, we show that the formation of such ultra-slow solitons in cold atomic systems is a fairly universal phenomenon.展开更多
For two-component disk-shaped Bose-Einstein condensates with repulsive atom-atom interaction, the small amplitude, finite and long wavelength nonlinear waves can be described by a Kadomtsev-Petviashvili-Ⅰ equation at...For two-component disk-shaped Bose-Einstein condensates with repulsive atom-atom interaction, the small amplitude, finite and long wavelength nonlinear waves can be described by a Kadomtsev-Petviashvili-Ⅰ equation at the lowest order from the originai coupled Gross-Pitaevskii equations. One- and two-soliton solutions of the Kadomtsev- Petviashvili-1 equation are given, therefore, the wave functions of both atomic gases are obtained as well. The instability of a soliton under higher-order long wavelength disturbance has been investigated. It is found that the instability depends on the angle between two directions of both soliton and disturbance.展开更多
To analyze the stability problem of spatial beam structure more accurately, a spatial cubic spline geometric nonlinear beam dement was proposed considering the seeond-order effect. The deformation field was built with...To analyze the stability problem of spatial beam structure more accurately, a spatial cubic spline geometric nonlinear beam dement was proposed considering the seeond-order effect. The deformation field was built with cubic spline function, and its curvature degree of freedom （DOF） was eliminated by static condensation method. Then we got the geometric nonlinear stiffness matrix of the new spatial two.node Euler-Bernouili beam dement. Several examples proved calculation accuracy of the critical load by meshing a bar to one element using the method of this paper was equivalent to mesh a bar to 3 or 4 traditional nonlinear beam dements.展开更多
The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton （CCA）. The calculations are done on various sizes of the simple cubic lattice in the 0 ...The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton （CCA）. The calculations are done on various sizes of the simple cubic lattice in the 0 ≤ D/J ≤ 5 parameter region. The phase diagram of the model and temperature variation of the thermodynamic quantities are obtained. We confirm the existence of a critical end point within the heating calculations. However, in contrast to the heating calculations, we do not obtain the first-order line at low temperature with cooling algorithm calculations. The results are compared with those of other theories.展开更多
CDC48 is a highly conserved protein in eukaryotes and belongs to the AAA （ATPase associated with a variety of cellular activities） superfamily. It can interact with many different cofactors and form protein complexe...CDC48 is a highly conserved protein in eukaryotes and belongs to the AAA （ATPase associated with a variety of cellular activities） superfamily. It can interact with many different cofactors and form protein complexes that play important roles in various cellular processes. According to the Physcomitrella patens database, one member of the ATPases, the cell cycle gene PpCDC4811, was cloned. PpCDC48II contains two typical ATPase modules and is highly homologous to AtCDC48A. PpCDC4811 was up-regulated in mRNA levels after incubation at 0~C for 36 and 72 h. To further elucidate protein function, we disrupted the PpCDC4811 gene by transforming P. patens with the corresponding linear genomic sequences. When treated to the same freezing stress, it was found that PpCDC4811 knockout plants were less resistant to freezing treatment than wild type after acclimation. This suggested that PpCDC481I was an essential gene for low-temperature-induced freezing tolerance in P. patens cells.展开更多
The dual-cooled nuclear reactor is currently considered for improving the designs of current/future nuclear reactors. Investigation of the thermal-hydraulic characteristics of the nuclear reactor via experiments is es...The dual-cooled nuclear reactor is currently considered for improving the designs of current/future nuclear reactors. Investigation of the thermal-hydraulic characteristics of the nuclear reactor via experiments is essential for commercializing the dual-cooled nuclear reactor. In this paper, the turbulent flow in square arrayed six-rod bundles in the form of magnified copies of the dual-cooled and current OPR-1000 nuclear reactor is experimentally investigated by means of hot-wire anemometry and smoke-wire generation methods. Vortex trains which do not exist in an ordinary reactor subchannel are presented in the subchannel of the dual-cooled reactor. The vortices are induced by a span-wise velocity gradient. This flow pulsation phenomenon increases the inter-channel mixing of the subchannel. To understand the periodic feature of the pulsation, axial/cross velocities are measured and the periodic characteristic frequencies are obtained by a Fast Fourier Transform (FFT) analysis. The peak frequency that represents the quasi-periodic pulsation of the flow is increased with an increase in the axial velocity while the wavelength of the pulsation remains constant within a tested range of the Reynolds number (9000 51000). The vortex trains are highly synchronized with each other, as confirmed by means of visualization.展开更多
基金Supported by the Science and Technology Programof EducationDepartment of Hubei Province under Grant No.B20052202 ,andthe Fund of Natural Science of Hubei Province under Grant No.2004ABA112
文摘The statics characteristics of two coupled Bose-Einstein condensate (BEC) dark solitons trapped in an optical lattice are investigated with the variational approach.It is found that the interaction between a ‘kink’ and an ‘anti-kink’ with opposite phase gradients is effectively repulsive, and the optical lattice can be controllably used to produce a pair of static BEC dark solitons.Its effect depends on the initial location of the BEC dark solitons, the lattice amplitude and wave number.
基金The project supported by Natioual Natural Science Foundation of China under Grant Nos. 1057508 and 10302018 and the Natural Science Foundation of Zhejiang Province of China under Grant No. Y605056The authors would like to thank Prof. Sen-Yue Lou for helpful discussions.
文摘Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method, we successfully obtain periodic wave solutions and solitary wave solutions, including the bright and dark soliton solutions.The results in this paper include some in the literatures [Phys. Rev. Lett. 94 （2005） 050402 and Chin. Phys. Left. 22 （2005） 1855].
基金The project supported by National Natural Science Foundation of China under Grant Nos. 60478029, 90503010, 10575040 and 10125419 and the National Fundamental Research Program of China under Grant Nos. 2005CB724508 and 2001CB309310
文摘We present a systematic study on the formation of ultra-slow bright and dark optical solitons in highly resonant media. By investigating four life-time broadened atomic systems, i.e., three-state A-type and cascade-type schemes, and four-state N-type and cascade-type schemes, we show that the formation of such ultra-slow solitons in cold atomic systems is a fairly universal phenomenon.
基金National Natural Science Foundation of China under Grant No.10575082the Natural Science Foundation of Gansu Province under Grant No.3ZS061-A25-013the Natural Science Foundation of Northwest Normal University under Grant No.NWNU-KJCXGC-013-17
文摘For two-component disk-shaped Bose-Einstein condensates with repulsive atom-atom interaction, the small amplitude, finite and long wavelength nonlinear waves can be described by a Kadomtsev-Petviashvili-Ⅰ equation at the lowest order from the originai coupled Gross-Pitaevskii equations. One- and two-soliton solutions of the Kadomtsev- Petviashvili-1 equation are given, therefore, the wave functions of both atomic gases are obtained as well. The instability of a soliton under higher-order long wavelength disturbance has been investigated. It is found that the instability depends on the angle between two directions of both soliton and disturbance.
文摘To analyze the stability problem of spatial beam structure more accurately, a spatial cubic spline geometric nonlinear beam dement was proposed considering the seeond-order effect. The deformation field was built with cubic spline function, and its curvature degree of freedom （DOF） was eliminated by static condensation method. Then we got the geometric nonlinear stiffness matrix of the new spatial two.node Euler-Bernouili beam dement. Several examples proved calculation accuracy of the critical load by meshing a bar to one element using the method of this paper was equivalent to mesh a bar to 3 or 4 traditional nonlinear beam dements.
基金Supported by the Scientific and Technological Research Council of Turkey (TBITAK) under Grant No. 109T018
文摘The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton （CCA）. The calculations are done on various sizes of the simple cubic lattice in the 0 ≤ D/J ≤ 5 parameter region. The phase diagram of the model and temperature variation of the thermodynamic quantities are obtained. We confirm the existence of a critical end point within the heating calculations. However, in contrast to the heating calculations, we do not obtain the first-order line at low temperature with cooling algorithm calculations. The results are compared with those of other theories.
基金supported by the National Natural Science Foundation of China (Grant No. 30700404)
文摘CDC48 is a highly conserved protein in eukaryotes and belongs to the AAA （ATPase associated with a variety of cellular activities） superfamily. It can interact with many different cofactors and form protein complexes that play important roles in various cellular processes. According to the Physcomitrella patens database, one member of the ATPases, the cell cycle gene PpCDC4811, was cloned. PpCDC48II contains two typical ATPase modules and is highly homologous to AtCDC48A. PpCDC4811 was up-regulated in mRNA levels after incubation at 0~C for 36 and 72 h. To further elucidate protein function, we disrupted the PpCDC4811 gene by transforming P. patens with the corresponding linear genomic sequences. When treated to the same freezing stress, it was found that PpCDC4811 knockout plants were less resistant to freezing treatment than wild type after acclimation. This suggested that PpCDC481I was an essential gene for low-temperature-induced freezing tolerance in P. patens cells.
基金carried out under the Nuclear R&D Program supported by the Ministry of Education, Science and Technology of the Republic of Korea (Grant No. NRF-2012M2A8A5025824)the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (Grant No. 2012-0005727)
文摘The dual-cooled nuclear reactor is currently considered for improving the designs of current/future nuclear reactors. Investigation of the thermal-hydraulic characteristics of the nuclear reactor via experiments is essential for commercializing the dual-cooled nuclear reactor. In this paper, the turbulent flow in square arrayed six-rod bundles in the form of magnified copies of the dual-cooled and current OPR-1000 nuclear reactor is experimentally investigated by means of hot-wire anemometry and smoke-wire generation methods. Vortex trains which do not exist in an ordinary reactor subchannel are presented in the subchannel of the dual-cooled reactor. The vortices are induced by a span-wise velocity gradient. This flow pulsation phenomenon increases the inter-channel mixing of the subchannel. To understand the periodic feature of the pulsation, axial/cross velocities are measured and the periodic characteristic frequencies are obtained by a Fast Fourier Transform (FFT) analysis. The peak frequency that represents the quasi-periodic pulsation of the flow is increased with an increase in the axial velocity while the wavelength of the pulsation remains constant within a tested range of the Reynolds number (9000 51000). The vortex trains are highly synchronized with each other, as confirmed by means of visualization.
