A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extende...A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extended to a few atoms with N 〉2. It is found that all 2N atoms can be entangled in the form of NOON states if the atoms in the first cavity are initially in the excited states and atoms in the second cavity are all in the ground states. The feasibility of the scheme is carefully discussed, it shows that the NOON state with a few atoms can be generated with good fidelity and the scheme is feasible in experiment.展开更多
Two coaxial vertical cylinders-one is a riding hollow cylinder and the other a solid cylinder of greater radius at some distance above an impermeable horizontal bottom,were considered.This problem of diffraction by th...Two coaxial vertical cylinders-one is a riding hollow cylinder and the other a solid cylinder of greater radius at some distance above an impermeable horizontal bottom,were considered.This problem of diffraction by these two cylinders,which were considered as idealization of a buoy and a circular plate,can be considered as a wave energy device.The wave energy that is created and transferred by this device can be appropriately used in many applications in lieu of conventional energy.Method of separation of variables was used to obtain the analytical expressions for the diffracted potentials in four clearly identified regions.By applying the appropriate matching conditions along the three virtual boundaries between the regions,a system of linear equations was obtained,which was solved for the unknown coefficients.The potentials allowed us to obtain the exciting forces acting on both cylinders.Sets of exciting forces were obtained for different radii of the cylinders and for different gaps between the cylinders.It was observed that changes in radius and the gap had significant effect on the forces.It was found that mostly the exciting forces were significant only at lower frequencies.The exciting forces almost vanished at higher frequencies.The problem was also investigated for the base case of no plate arrangement,i.e.,the case having only the floating cylinder tethered to the sea-bed.Comparison of forces for both arrangements was carried out.In order to take care of the radiation of the cylinders due to surge motion,the corresponding added mass and the damping coefficients for both cylinders were also computed.All the results were depicted graphically and compared with available results.展开更多
We have studied the temporal bond polarisabilities of para-nitroaniline from the Raman intensities by the algorithm proposed by Wu et al. in 1987 （Tian B, Wu G, Liu G 1987 J. Chem. Phys. 87 7300）. The bond polarisab...We have studied the temporal bond polarisabilities of para-nitroaniline from the Raman intensities by the algorithm proposed by Wu et al. in 1987 （Tian B, Wu G, Liu G 1987 J. Chem. Phys. 87 7300）. The bond polarisabilities provide much information concerning the electronic structure of the non-resonant Raman excited virtual state. At the initial moment by the 514.5 nm excitation, the tendency of the excited electrons （mapped out by the bond polarisabilities） is to spread to the molecular periphery, and the electronic structure of the Raman virtual state is close to the pseudoquinonoidic state. When the final stage of relaxation is approached, the bond polarisabilities of those peripheral bonds relax faster than those closer to the molecular core, the phenyl ring. The molecule is in the benzenoidic form as demonstrated by the bond polarisabilities after relaxation.展开更多
A scheme for one-step preparation of atomic GHZ states in two directly coupled cavities via virtual excitations is proposed.In the whole procedure,the information is carried only in two ground states of A-type atoms, ...A scheme for one-step preparation of atomic GHZ states in two directly coupled cavities via virtual excitations is proposed.In the whole procedure,the information is carried only in two ground states of A-type atoms, while the excited states of atoms and cavity modes are virtually excited,leading the system to be insensitive to atomic spontaneous emission and photon loss.展开更多
The exciter component in a panel loudspeaker has a profound effect on the overall performance of the system. The equivalent circuit analysis of the combination of giant magnetostrictive material exciter and distribute...The exciter component in a panel loudspeaker has a profound effect on the overall performance of the system. The equivalent circuit analysis of the combination of giant magnetostrictive material exciter and distributed mode panel is introduced and how exciter parameters influence panel lo＇udspeaker＇ s performance is discussed. Numerical predictions are given in order to show how these influences are manifested.展开更多
驮背运输是一种“门到门”运输的公铁联运方式,近些年得到国家的高度重视。文中以STX3型驮背运输车为研究对象,基于虚拟样机技术,分别利用Simpack建立刚柔耦合模型和驮背运输车随机振动分析软件(the Professional Software for the Rand...驮背运输是一种“门到门”运输的公铁联运方式,近些年得到国家的高度重视。文中以STX3型驮背运输车为研究对象,基于虚拟样机技术,分别利用Simpack建立刚柔耦合模型和驮背运输车随机振动分析软件(the Professional Software for the Random Vibration Analysis of Piggyback Traffic Vehicles,PRAP)建立车辆的精细有限元动力学模型,以轨道不平顺谱作为输入激励,进行仿真计算得到车辆的振动特性,并与试验结果进行对比分析研究。研究结果表明:仿真计算及试验得到的驮背车最大振动加速度和平稳性指标均满足标准要求;驮背运输车随机振动分析软件计算得到的振动加速度及平稳性指标比刚柔耦合模型更为接近试验测量数据;转向架摇枕、侧架结构自身对激扰也具有衰减作用,摇枕能衰减来自枕簧的约10%的横向激扰和约14%的垂向激扰,侧架能衰减来自轴箱的约12%的横向激扰和约11%的垂向激扰。展开更多
基金Project supported in part by the National Natural Science Foundation of China (Grant Nos. 10974125 and 60821004)the State Basic Key Research Program of China (Grant No. 2006CB921102)the Science Foundation of the Educational Committee of Fujian Province, China (Grant No. JA09041)
文摘A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extended to a few atoms with N 〉2. It is found that all 2N atoms can be entangled in the form of NOON states if the atoms in the first cavity are initially in the excited states and atoms in the second cavity are all in the ground states. The feasibility of the scheme is carefully discussed, it shows that the NOON state with a few atoms can be generated with good fidelity and the scheme is feasible in experiment.
文摘Two coaxial vertical cylinders-one is a riding hollow cylinder and the other a solid cylinder of greater radius at some distance above an impermeable horizontal bottom,were considered.This problem of diffraction by these two cylinders,which were considered as idealization of a buoy and a circular plate,can be considered as a wave energy device.The wave energy that is created and transferred by this device can be appropriately used in many applications in lieu of conventional energy.Method of separation of variables was used to obtain the analytical expressions for the diffracted potentials in four clearly identified regions.By applying the appropriate matching conditions along the three virtual boundaries between the regions,a system of linear equations was obtained,which was solved for the unknown coefficients.The potentials allowed us to obtain the exciting forces acting on both cylinders.Sets of exciting forces were obtained for different radii of the cylinders and for different gaps between the cylinders.It was observed that changes in radius and the gap had significant effect on the forces.It was found that mostly the exciting forces were significant only at lower frequencies.The exciting forces almost vanished at higher frequencies.The problem was also investigated for the base case of no plate arrangement,i.e.,the case having only the floating cylinder tethered to the sea-bed.Comparison of forces for both arrangements was carried out.In order to take care of the radiation of the cylinders due to surge motion,the corresponding added mass and the damping coefficients for both cylinders were also computed.All the results were depicted graphically and compared with available results.
基金Project supported by the Natural Science Foundation of Beijing,China (Grant No. 2082006)the National Natural Science Foundation of China (Grant No. 20773073)+1 种基金the Key Grant Project of Chinese Ministry of Education (Grant No. 306020)the Special Research Fund for the Doctoral Program of Higher Education,China (Grant No. 20060003050)
文摘We have studied the temporal bond polarisabilities of para-nitroaniline from the Raman intensities by the algorithm proposed by Wu et al. in 1987 （Tian B, Wu G, Liu G 1987 J. Chem. Phys. 87 7300）. The bond polarisabilities provide much information concerning the electronic structure of the non-resonant Raman excited virtual state. At the initial moment by the 514.5 nm excitation, the tendency of the excited electrons （mapped out by the bond polarisabilities） is to spread to the molecular periphery, and the electronic structure of the Raman virtual state is close to the pseudoquinonoidic state. When the final stage of relaxation is approached, the bond polarisabilities of those peripheral bonds relax faster than those closer to the molecular core, the phenyl ring. The molecule is in the benzenoidic form as demonstrated by the bond polarisabilities after relaxation.
基金Supported in part by the Natural Science Foundation of China under Grant Nos.10974125,60821004,60878059in part by the Educational Committee of Fujian Province under Grant No.JA09041in part by Fujian Normal University under Grant No.2008100220
文摘A scheme for one-step preparation of atomic GHZ states in two directly coupled cavities via virtual excitations is proposed.In the whole procedure,the information is carried only in two ground states of A-type atoms, while the excited states of atoms and cavity modes are virtually excited,leading the system to be insensitive to atomic spontaneous emission and photon loss.
文摘The exciter component in a panel loudspeaker has a profound effect on the overall performance of the system. The equivalent circuit analysis of the combination of giant magnetostrictive material exciter and distributed mode panel is introduced and how exciter parameters influence panel lo＇udspeaker＇ s performance is discussed. Numerical predictions are given in order to show how these influences are manifested.
文摘驮背运输是一种“门到门”运输的公铁联运方式,近些年得到国家的高度重视。文中以STX3型驮背运输车为研究对象,基于虚拟样机技术,分别利用Simpack建立刚柔耦合模型和驮背运输车随机振动分析软件(the Professional Software for the Random Vibration Analysis of Piggyback Traffic Vehicles,PRAP)建立车辆的精细有限元动力学模型,以轨道不平顺谱作为输入激励,进行仿真计算得到车辆的振动特性,并与试验结果进行对比分析研究。研究结果表明:仿真计算及试验得到的驮背车最大振动加速度和平稳性指标均满足标准要求;驮背运输车随机振动分析软件计算得到的振动加速度及平稳性指标比刚柔耦合模型更为接近试验测量数据;转向架摇枕、侧架结构自身对激扰也具有衰减作用,摇枕能衰减来自枕簧的约10%的横向激扰和约14%的垂向激扰,侧架能衰减来自轴箱的约12%的横向激扰和约11%的垂向激扰。
