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31.
B.M.I. vanderZande S.J. Roosendaal C. Doornkamp J. Steenbakkers J. Lub 《Advanced functional materials》2006,16(6):791-798
Mixtures of liquid‐crystalline di‐oxetanes and mono‐oxetanes are made for the purpose of making birefringent films by photopolymerization. The composition of a di‐oxetane mixture that forms spin‐coated films of planarly aligned nematic monomers is reported. These films are photopolymerized in air. The molecular order of the monomers can be changed on the microscale to form thin films with alternating birefringent and isotropic parts by using a combination of photopolymerization and heating. The interface observed between the birefringent and isotropic 10 μm × 10 μm domains is very sharp and the films show hardly any surface corrugation. In addition, the polymerized films are thermally stable, making them very suitable for use as patterned thin‐film retarders in high‐performance transflective liquid‐crystal displays (LCDs) which satisfy customer demand for displays that are brighter and thinner and that deliver better optical performance than conventional LCDs with an external non‐patterned retarder. 相似文献
32.
An efficient return algorithm for non-associated plasticity with linear yield criteria in principal stress space 总被引:1,自引:0,他引:1
An efficient return algorithm for stress update in numerical plasticity computations is presented. The yield criterion must be linear in principal stress space and can be composed of any number of yield planes. Each of these yield planes may have an associated or non-associated flow rule. The stress return and the formation of the constitutive matrix is carried out in principal stress space. Here the manipulations simplify and rely on geometrical arguments. The singularities arising at the intersection of yield planes are dealt with in a straightforward way also based on geometrical considerations. The method is exemplified on non-associated Mohr–Coulomb plasticity throughout the paper. 相似文献
33.
Mou Weimin; Biocca Frank; Owen Charles B.; Tang Arthur; Xiao Fan; Lim Lynette 《Canadian Metallurgical Quarterly》2004,10(4):238
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Plastic instability in dual-pressure tube-hydroforming process 总被引:1,自引:0,他引:1
The tube-hydroforming process has become an indispensable manufacturing technique in recent years. Successful tube hydroforming requires bulging to take place without causing any type of instability such as bursting, wrinkling or buckling. The dual-pressure tube-hydroforming process was introduced to achieve a favorable tri-axial stress state in the deformation process. In this paper, the effect of applying counter pressure on plastic instability of thin-walled tubes is analyzed. It is concluded that in dual-pressure tube hydroforming, the onset of plastic instability is delayed and the ductility of the metal is increased. 相似文献
35.
设计一电路,将彩色图象信息编码到黑白CRT的亮度之中,并将其写入液晶光阀,用白光读出,当编码合适时,读出的象颜色可与原图像一致。本文讨论了这一技术原理并进行了单液晶光阀彩色大屏幕投影的实验验证。 相似文献
36.
Mitsutoshi Miyasaka 《Journal of the Society for Information Display》2007,15(7):479-484
Abstract— Suftla is a technology that is used to transfer polycrystalline silicon (polysilicon) thin‐film‐transistor (TFT) circuits from an original glass substrate to a plastic sheet. The electronic devices in the next generation will be thin, lightweight, and will handle huge amounts of data, yet consume less energy. Suftla technology, together with high‐performance polysilicon TFTs, meets all these requirements because we have developed a variety of smart flexible electronic devices, such as thin paperback‐sized displays and microprocessors. Suftla will usher in a new era of life‐enhancing flexible microelectronics. 相似文献
37.
矫直状态下钢管弹塑性变形区的研究 总被引:2,自引:0,他引:2
根据钢管矫直时的变形规律,通过对矫直中钢管的力学状态及矫直前后的状态参数分析,建立了一种适于现场应用的确定钢管弹、塑性变形区的新方法。 相似文献
38.
Joonyoung Park Sung-Hwan Han S. Senthilarasu Soo-Hyoung Lee 《Solar Energy Materials & Solar Cells》2007,91(8):751-753
Recent studies have reported that a thin interlayer between poly(3, 4-ethylene dioxythiophene)-poly(styrene sulfonic acid) (PEDOT: PSS) and an emissive polymer layer leads to a large increase in the performances of polymer light-emitting diodes (PLEDs) by preventing significant quenching of the radiative excitons at the PEDOT: PSS interface; therefore, acting as an efficient exciton-blocking layer. Using the similar idea, a thin interlayer was fabricated between PEDOT: PSS and the active layer of conjugated polymers/methanofullerene composites in a plastic solar cell. The interlayer consisted of a poly(fluorene)-based hole transporter spin-coated directly on top of the PEDOT: PSS layer. The devices with the interlayer exhibited a higher efficiency than in those without the interlayer. 相似文献
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