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71.
WU Yanga JIANG Xiao-Yub ZHANG Quan-Zhengc CHEN Li-Juanc YU Ya-Qinc CHEN Shu-Meic HE Xiangc YANG Wen-Binc LU Can-Zhongc② a 《结构化学》2005,24(3):291-294
1 INTRODUCTION Current research interest is focused on the designof structures built up from octahedral and tetrahedralbuilding blocks[1]. During the wide investigations intransition-metal phosphates for many years, a num-ber of new mixed transition-metal phosphates havebeen reported[2]. A great number of manganese phos-phates were largely discovered as minerals[1]. On theother hand, many vanadium phosphates have alsobeen prepared recently partly because of their poten-tial applications … 相似文献
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73.
Effective simulation of flexible lateral boundaries in two- and three-dimensional DEM simulations 总被引:5,自引:0,他引:5
Discrete element method (DEM) models to simulate laboratory element tests play an important role in advancing our understanding of the mechanics of granular material response, including bonded or cemented, particulate materials. Comparisons of the macro-scale response observed in a real physical test and a "virtual" DEM-simulated test can calibrate or validate DEM models. The detailed, particle scale information provided in the DEM simulation can then be used to develop our understanding of the material behaviour. It is important to accurately model the physical test boundary conditions in these DEM simulations. This paper specifically considers triaxial tests as these tests are commonly used in soil mechanics. In a triaxial test, the test specimen of granular material is enclosed within a flexible latex membrane that allows the material to deform freely during testing, while maintaining a specified stress condition. Triaxial tests can only be realistically simulated in 3D DEM codes, however analogue, 2D, biaxial DEM simulations are also often considered as it is easier to visualize particle interactions in two dimensions. This paper describes algorithms to simulate the lateral boundary conditions imposed by the latex membrane used in physical triaxial tests in both 2D and 3D DEM simulations. The importance of carefully considering the lateral boundary conditions in DEM simulations is illustrated by considering a 2D biaxial test on a specimen of frictional unbonded disks and a 3D triaxial test on a bonded (cemented) specimen of spheres. The comparisons indicate that the lateral boundary conditions have a more significant influence on the local, particle-scale response in comparison with the overall macro-scale observations. 相似文献
74.
本文提出的灰度/深度图象序列的三维内插方法,摆脱了原实摄路径限制,可在空间内任意巡行。采用空间稀疏化采样,从而达到大量节省存储量和高度灵活地可控再现空间场景的目的,为解决三维内插中庞大的计算量,本文研究了快速而实用的散点算法和深度适应的Warp算法,通过介绍三维内插的几种简单情形,导出了一些简单,实用的算法。计算机仿真结果显示了这一新方法是完全可行的。 相似文献
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With N,N′-bis(benzimidazol-2-methyl)amine as the ligand,a novel Cu(Ⅱ) dinuclear complex was synthesized as a mimetic compound of superoxide dismutase(SOD).The complex was characterized with element analysis,UV and IR spectra.The crystal structure was determined by using X-ray diffraction analysis.the crystal structure shows that Cu(Ⅱ) and its coordinated atoms construct distorted octahedron configuration with oxygen atome of (ClO4-)s in the axial directions.The coordinated cations are linked by (ClO4-)s to form nonplanar sheets.All sheets are linked together into three-dimensional network by the intermolecular hydrogen bonds.The result of the activity assay indicates that the complex does have certain biological activity. 相似文献
77.
HL-2A装置边缘等离子体测地声模带状流的三维特征采用外中平面上三组三台阶探针阵列组成具有环向、极向和径向分辨的独特结构的探针系统进行了研究.其中两组具有极向距离为65mm的三台阶5探针阵列组成极向带状流10探针组,另一组电动式带状流6探针阵列与带状流10探针组之间的环向距离为800mm. 此外,采用快速往复气动6探针组研究了磁分界面附近的温度、密度、雷诺协强及其径向分布.在HL-2A装置上同时观测到测地声模带状流(频率f=7kHz)的极向和环向对称性(m≈0,n
关键词:
三台阶式ZF探针
带状流
三维空间结构 相似文献
78.
HL-2A装置边缘等离子体测地声模带状流的三维特征采用外中平面上三组三台阶探针阵列组成具有环向、极向和径向分辨的独特结构的探针系统进行了研究.其中两组具有极向距离为65mm的三台阶5探针阵列组成极向带状流10探针组,另一组电动式带状流6探针阵列与带状流10探针组之间的环向距离为800mm. 此外,采用快速往复气动6探针组研究了磁分界面附近的温度、密度、雷诺协强及其径向分布.在HL-2A装置上同时观测到测地声模带状流(频率f=7kHz)的极向和环向对称性(m≈0,n 相似文献
79.
自然界存在4种相互作用(强作用、弱作用、电磁作用和万有引力作用),它们的强度相差很大.如果以强作用的强度定为1,则电磁作用为10-2,弱作用为10-14,而引力作用为10-39.引力相互作用与强、弱、电磁作用相比太微弱了,完全可以忽略不计. 相似文献
80.
电磁场统一性质的三维描述 总被引:1,自引:0,他引:1
论述了电场与磁场本质上的统一性质,构造了三维空间中电磁场的统一场量,给出它的方程、场量的模方与能量和动量的关系,发现三维空间中的统一场量自身的标积竟然是相对论变换下的不变量. 相似文献