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201.
Published data and the author's own results on the creation of organic luminophores with anomalously high fluorescence Stokes' shifts are reviewed.  相似文献   
202.
The key modules in a typical reverse engineering system consist of the acquisition, registration, and the integration of range images of three-dimensional objects with complex geometry. We first present a self-made optical digitizer that is employed for quickly acquiring range data from multiple views, then introduce a visualized registration procedure that can provide a reliable estimate for the fine registration of multiple range images in a unified coordinate system. Experiment results are given to show the effectiveness of this approach in 3-D imaging and multiple range image registration for the applications of reverse engineering.  相似文献   
203.
204.
An efficient algorithm is developed for solving linear programs with an additional reverse convex constraint having a special structure. Computational results are presented and discussed.  相似文献   
205.
In this paper, we give the definition of weak WT2-class of differential forms, and then obtain its weak reverse Holder inequality. As an application, we give an alternative proof of the higher integrability result of weakly A-harmonic tensors due to B. Stroffolini.  相似文献   
206.
Abstract

In order to develop an easy and rapid identification method for distinguishing CH3OH from C2H5OH, a new carbonate-based trinuclear Cu(II) precursor, [Cu3(bpy)63-CO3)(CH3OH)](BF4)4·(CH3OH)2·(H2O)2 (1), has been isolated. We report here the synthesis, crystal structure, and characterizations by various spectroscopic (IR, UV–Vis, powder XRD) techniques, as well as the solvatochromic behavior of this coordination compound. Its X-ray crystal structure reveals that the main structure of 1 consists of three [(bpy)2Cu]2+ centers, which are bridged by carbonate via a μ3111 fashion. Strong O–H?O hydrogen bonding between the carbonate and solvent molecules has been observed for the first time in similar structures. Its ground powder exhibits solvatochromic behavior that selectively distinguishes CH3OH from C2H5OH.  相似文献   
207.
在停车楼的设计中通常将车辆荷载以活荷载的方式均匀分布到结构上,实际上受车辆随机停放的影响,停车楼结构整体质量中心偏移,一旦结构遭遇罕遇地震时,车辆的随机停放可能造成停车楼结构发生扭转破坏.本文在传统减震设计方法的基础上考虑车辆活荷载的随机性,并从可靠度的角度验算减震结构在大震作用下的倒塌概率.结果表明,相同的减震设计布...  相似文献   
208.
According to the behaviors of a bubble in the ship wake flow,the numerical simulation is divided into two stages,quasi-spherical motion and non-spherical motion,based on whether the bubble is captured by the vortex or not.The one-way coupled particle tracking method(PTM) and the boundary element method(BEM) are adopted to simulate these two stages,respectively.Meanwhile,the initial condition of the second stage is taken as the output of the first one,and the entire simulation is connected and completed.Based on the numerical results and the published experimental data,the cavitation inception is studied,and the wake bubble is tracked.Besides,the split of the bubble captured by the vortex and the following sub-bubbles are simulated,including motion,deformation,and collapse.The results provide some insights into the control on wake bubbles and optimization of the wake flow.  相似文献   
209.
The paper is concerned with the generalization of synthetic theory to the modeling of phenomena such as the Bauschinger negative effect,creep delay,reverse and inverse creep.Detailed calculations of pl...  相似文献   
210.
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