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111.
Guo Q Brodzeli Z Pozhidaev EP Fan F Chigrinov VG Kwok HS Silvestri L Ladouceur F 《Optics letters》2012,37(12):2343-2345
The electro-optical behavior of deformed helix ferroelectric liquid crystal in reflective mode is described in this paper. The electrically controlled reflectance has been measured at subkilohertz driving voltage frequency for different polarizations of the incident light and compared quite successfully with the simulation results. 相似文献
112.
113.
We report on a novel concept of sample loading for microfluidic devices using a benchtop centrifuge and a magnetically actuated circular closed-loop PCR microchip as a model system. The PCR mixture and the ferrofluid were loaded into a specially designed microchip. The microchip was then placed in an off-the-shelf 50-mL tube and centrifuged. The strong centrifugal force drives the PCR mixture and the ferrofluid into the microchannels of the microchip, and simultaneously expels any trapped microbubbles. PCR was successfully carried out on single and parallel closed-loop PCR microchips. The addition of a few off-chip handling steps allows great simplification of the device design. This new loading concept may be useful for designing robust and low-cost lab-on-a-chip devices because benchtop centrifuges are quite common in most laboratories. Figure
This paper reports a novel concept of sample loading for microfluidic devices using a benchtop centrifuge. The addition of a few simple off-chip handling steps allows designing robust and low-cost lab-on-a-chip devices. 相似文献
114.
This work examines the cooperative motion of a group of autonomous vehicles in a fast flow environment. The magnitude of the flow velocity is assumed to be greater than the available actuation to each agent. Collectively, the agents wish to maximize total coverage area defined as the set of points reachable by any agent within T time. The reachable set of an agent in a fast flow is characterized using optimal control techniques. Specifically, this work addresses the complementary cases where the static flow field is smooth, and where the flow field is piecewise constant. The latter case arises as a proposed approximation of a smooth flow that remains analytically tractable. Furthermore, the techniques used in the piecewise constant flow case enable treatment for obstacles in the environment. In both cases, a gradient ascent method is derived to maximize the total coverage area in a distributed fashion. Simulations show that such a network is able to maximize the coverage area in a fast flow. 相似文献
115.
We analyze a least-squares asymmetric radial basis function
collocation method for solving the modified Helmholtz equations. In
the theoretical part, we proved the convergence of the proposed
method providing that the collocation points are sufficiently dense.
For numerical verification, direct solver and a subspace selection
process for the trial space (the so-called adaptive greedy
algorithm) is employed, respectively, for small and large scale
problems. 相似文献
116.
对原型双跨复合梁的结构行为给出了详细的有限元研究.由于基本上认为剪切连接件是非刚性的,在高等有限元模型中采用弹簧单元可以将它们的非线性荷载一滑移性质考虑在内.对各种原型双跨复合梁进行了参数研究,并提出了主要的研究结果.主要的结构参数包括剪切连接件在正弯矩和负弯矩区域内的变形韧性和变形程度.总共比较和讨论了9个具有不同类型和剪切件数目的复合梁的结构行为,对目前的设计缺陷进行了鉴定.由于提出的有限元模型对详细调查复合梁的结构行为非常有效,有效地利用所提出的模型将对更具有改善结构精度和效率的细化设计准则的发展有帮助. 相似文献
117.
118.
Recent studies have revealed that the fractional derivative can behave as a dissipative term. The analysis of a simple fractional oscillator has supported this point of view. However, other physical aspects related to fractional derivative are also important to be explored. For this purpose, in this work, we employ the fractional approach and guide ourselves by the above property to investigate the falling body problem. We show that the velocity of a falling body, in the fractional approach, can be greater (t<1) or less (t>1) than that velocity of free-fall obtained by the usual approach. Moreover, we show that the fractional derivative alone is not sufficient to attain a terminal speed. In order to provide a terminal speed into the fractional system a term, proportional to velocity, must be introduced. 相似文献
119.
Wei‐Yu Bi Xing‐Qiang Lü Wen‐Li Chai Ji‐Rong Song Wai‐Kwok Wong Xiao‐Ping Yang Richard A. Jones 《无机化学与普通化学杂志》2008,634(10):1795-1800
Two heterobimetallic Zn‐Nd phenylene‐bridged Schiff‐base ligands complexes [ZnNd L1 (Py)(NO3)3] ( 1 ) and [Zn L2 Nd(Py)(NO3)3]·MeCN ( 2 ) (Py = pyridine, H2L1 = N,N′‐bis‐ (3‐methoxy‐salicylidene)phenylene‐1,2‐diamine, H2L2 = N,N′‐bis‐5‐bromo‐3‐methoxy‐salicylidene)phenylene‐1,2‐diamine) were obtained. Both 1 and 2 were structurally characterized by X‐ray crystallography, and their near‐infrared (NIR) luminescent properties were determined. For the two complexes, the occupation of pyridine at the axial position of 3d Zn2+ ions could effectively prevent luminescent quenching arising from OH‐, NH‐ or CH oscillators of the solvates around the 4f Nd3+ ions, and the heavy‐atom (Br) effect of the Schiff‐base ligands on their NIR luminescent properties is also discussed. 相似文献
120.