河口动力机制复杂,生态环境敏感脆弱,珠江三角洲咸潮上溯距离逐年上移,对生态环境造成了巨大的影响。咸潮上溯距离受径流和潮汐影响显著。该文采用物理模型试验方法,对径流和潮汐共同作用下的咸潮上溯距离进行分析,结果表明:1)增加上游...河口动力机制复杂,生态环境敏感脆弱,珠江三角洲咸潮上溯距离逐年上移,对生态环境造成了巨大的影响。咸潮上溯距离受径流和潮汐影响显著。该文采用物理模型试验方法,对径流和潮汐共同作用下的咸潮上溯距离进行分析,结果表明:1)增加上游径流量,引起河道水力坡度变陡使得咸界整体往下移动;2)存在临界潮差,使咸潮涨憩时上溯距离最小;3)上游同样增加相同径流量时,潮差小时咸界下移距离大于潮差大时的咸界下移。最后利用Fischer的分层-环流图阐述了产生其偏差的机理:一方面当潮差小时,引起的分层系数变化和/s fu u变化幅值更大;另一方面,增加径流量时改变了密度环流输运作用,而潮差较小时密度环流输运是主导因素,此时增大的径流量,改变了主导因素的输运比例,引起了较大的作用效果,反之,潮差大时作用效果则较小。展开更多
In this work, we propose an algebraic recursion method to study the dynamical evolution of the two-site Bose- Hubbard model. We analyze its properties from the viewpoints of single partite purity, energy, and trace di...In this work, we propose an algebraic recursion method to study the dynamical evolution of the two-site Bose- Hubbard model. We analyze its properties from the viewpoints of single partite purity, energy, and trace distance, in which the model is considered as a typical bipartite system. The analytical expressions for the quantities are derived. We show that the purity can well reflect the transition between different regimes for the system. In addition, we demonstrate that the transition from the delocalization regime to the self-trapping regime with the ratio r/increasing not only happens for an initially local state but also for any initial states. Furthermore, we confirm that the dynamics of the system presents a periodicity for η = 0 and the period is tc =π/2J when the initial state is symmetric.展开更多
We investigate the square-norm distance correlation dynamics of the Bell-diagonal states under different local deco- herence channels, including phase flip, bit flip, and bit-phase flip channels by employing the geome...We investigate the square-norm distance correlation dynamics of the Bell-diagonal states under different local deco- herence channels, including phase flip, bit flip, and bit-phase flip channels by employing the geometric discord （GD） and its modified geometric discord （MGD）, as the measures of the square-norm distance correlations. Moreover, an explicit comparison between them is made in detail. The results show that there is no distinct dominant relative ordering between them. Furthermore, we obtain that the GD just gradually deceases to zero, while MGD initially has a large freezing interval, and then suddenly changes in evolution. The longer the freezing interval, the less the MGD is. Interestingly, it is shown that the dynamic behaviors of the two geometric discords under the three noisy environments for the Werner-type initial states are the same.展开更多
文摘河口动力机制复杂,生态环境敏感脆弱,珠江三角洲咸潮上溯距离逐年上移,对生态环境造成了巨大的影响。咸潮上溯距离受径流和潮汐影响显著。该文采用物理模型试验方法,对径流和潮汐共同作用下的咸潮上溯距离进行分析,结果表明:1)增加上游径流量,引起河道水力坡度变陡使得咸界整体往下移动;2)存在临界潮差,使咸潮涨憩时上溯距离最小;3)上游同样增加相同径流量时,潮差小时咸界下移距离大于潮差大时的咸界下移。最后利用Fischer的分层-环流图阐述了产生其偏差的机理:一方面当潮差小时,引起的分层系数变化和/s fu u变化幅值更大;另一方面,增加径流量时改变了密度环流输运作用,而潮差较小时密度环流输运是主导因素,此时增大的径流量,改变了主导因素的输运比例,引起了较大的作用效果,反之,潮差大时作用效果则较小。
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91021009 and 21073110)
文摘In this work, we propose an algebraic recursion method to study the dynamical evolution of the two-site Bose- Hubbard model. We analyze its properties from the viewpoints of single partite purity, energy, and trace distance, in which the model is considered as a typical bipartite system. The analytical expressions for the quantities are derived. We show that the purity can well reflect the transition between different regimes for the system. In addition, we demonstrate that the transition from the delocalization regime to the self-trapping regime with the ratio r/increasing not only happens for an initially local state but also for any initial states. Furthermore, we confirm that the dynamics of the system presents a periodicity for η = 0 and the period is tc =π/2J when the initial state is symmetric.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11074002 and 61275119)the Natural Science Research Project of Education Department of Anhui Province,China(Grant No.KJ2013A205)
文摘We investigate the square-norm distance correlation dynamics of the Bell-diagonal states under different local deco- herence channels, including phase flip, bit flip, and bit-phase flip channels by employing the geometric discord （GD） and its modified geometric discord （MGD）, as the measures of the square-norm distance correlations. Moreover, an explicit comparison between them is made in detail. The results show that there is no distinct dominant relative ordering between them. Furthermore, we obtain that the GD just gradually deceases to zero, while MGD initially has a large freezing interval, and then suddenly changes in evolution. The longer the freezing interval, the less the MGD is. Interestingly, it is shown that the dynamic behaviors of the two geometric discords under the three noisy environments for the Werner-type initial states are the same.
