排序方式: 共有39条查询结果,搜索用时 46 毫秒
31.
合成了一个具有三维骨架结构的无机-有机杂化微孔材料Zn3(bpdc)3(4,4′- bpy)·DMF·2H2O,并通过ICP和X射线单晶衍射分析等手段对其结构进行了表征。 晶体属于正交晶系,Pbcn空间群,晶胞参数a=1.4532(3)nm,b=2.5037(5)nm,c=1. 8184(4)nm,V=6.616(2)nm^3,Z=8,Dc=1.296g/cm^3,Mr=645.58,μ=1.145mm^-1,F( 000)=2656。最后的一致性因子为R=0.0705,Rw=0.2056。 相似文献
32.
The Rayleigh-Taylor instability at the weakly nonlinear(WN) stage in spherical geometry is studied by numerical simulation.The mode coupling processes are revealed.The results are consistent with the WN model based on parameter expansion,while higher order effects are found to be non-negligible.For Legendre mode perturbation Pn(cos B),the nonlinear saturation amplitude(NS A) of the fundamental mode decreases with the mode number n.When n is large,the spherical NSA is lower than the corresponding... 相似文献
33.
在100 kJ激光装置上开展了基于三台阶整形脉冲的间接驱动惯性约束聚变内爆实验研究.采用传统充气直柱金壁黑腔设计,在激光脉冲作用后期,腔内金等离子体运动对激光能量沉积和X光辐射场空间分布产生严重扰动,导致靶丸赤道驱动偏弱,形成不可接受的扁圆内爆.本文采用新型的花生腔设计,通过调节外环激光光斑及其产生的金泡的初始位置,补偿和缓解金等离子体运动对黑腔X光辐射分布产生的扰动影响,获得球对称的靶丸辐射驱动.在靶丸驱动辐射温度相同的条件下,由于驱动对称性得到显著改善,实验观测到花生腔内爆热斑接近球形,中子产额的测量结果与内爆一维模拟计算结果的比值(YOS)达到30%;而直柱腔内爆热斑呈现扁圆形状, YOS仅为13%.模拟计算和实验结果一致表明,在三台阶整形脉冲驱动内爆实验中,花生腔设计可以有效抑制外环金泡膨胀加剧产生的不利因素,增强辐射驱动和内爆对称性调控,并提高内爆性能. 相似文献
34.
合成了一个具有三维骨架结构的无机 -有机杂化微孔材料Zn3(bpdc)3(4,4′ bpy)·DMF·2H2 O,并通过ICP和X射线单晶衍射分析等手段对其结构进行了表征.晶体属于正交晶系,Pbcn空间群,晶胞参数a =1.45 3 2 (3)nm,b =2.5 0 3 7(5 )nm,c=1.8184(4)nm,V =6.616(2 )nm3,Z =8,Dc=1.2 96g/cm3,Mr=64 5.5 8,μ =1.145mm-1,F(0 0 0)=2 65 6.最后的一致性因子为R =0.0 70 5,Rw =0.2 0 5 6. 相似文献
35.
Rayleigh–Taylor instability(RTI) of three incompressible fluids with two interfaces in spherical geometry is derived analytically. The growth rate on the two interfaces and the perturbation feedthrough coefficients between two spherical interfaces are derived. For low-mode perturbation, the feedthrough effect from outer interface to inner interface is much more severe than the corresponding planar case, while the feedback from inner interface to the outer interface is smaller than that in planar geometry. The low-mode perturbations lead to the pronounced RTI growth on the inner interface of a spherical shell that are larger than the cylindrical and planar results. It is the low-mode perturbation that results in the difference between the RTI growth in spherical and cylindrical geometry. When the mode number of the perturbation is large enough, the results in cylindrical geometry are recovered. 相似文献
36.
This paper investigates the interaction of a small number of modes in the two-fluid Kelvin-Helmholtz instability at the nonlinear regime by using a two-dimensional hydrodynamic code. This interaction is found to be relatively long range in wave-number space and also it acts in both directions, i.e. short wavelengths affect long wavelengths and vice versa. There is no simple equivalent transformation from a band of similar modes to one mode representing their effective amplitude. Three distinct stages of interaction have been identified. 相似文献
37.
38.
在水热条件下合成得到一系列具有SOD分子筛拓扑结构的稀土氧化物硝酸盐. 这些化合物的晶体结构都属于三方R-3空间群. 该种骨架结构使得SOD分子筛笼0.9 nm的直径被拓展至该结构中的近1.4 nm. 每个金属中心与8个氧原子配位, 其中6个为桥连氧原子, 2个氧原子来自配位的硝酸根. 如果忽略硝酸根, 可以把这个化合物看作是一个稀土氧化物的三维开放骨架结构, 这在稀土氧化物的结构中是非常少见的. 相似文献
39.
Interface Width Effect on the Weakly Nonlinear Rayleigh–Taylor Instability in Spherical Geometry
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Interface width effect on the spherical Rayleigh–Taylor instability in the weakly nonlinear regime is studied by numerical simulations.For Legendre perturbation mode Pn with wave number Kn and interface half-width L,the commonly adopted empirical linear growth rate formula γnem(L)=γn/√1 + KnL is found to be sufficient in spherical geometry.At the weakly nonlinear stage,the interface width affects the mode coupling processes.The development o... 相似文献