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101.
Jacob Belardi Nicolas Schorr Oswald Prucker Jürgen Rühe 《Advanced functional materials》2011,21(17):3314-3320
Magnetic artificial cilia are fabricated from photoreactive copolymer precursors filled with magnetic nanoparticles by a new photolithographic process. Two different crosslinkers and UV‐radiation of two different wavelengths are used to generate arrays of planar magnetically actuatable rubber flaps. The cilia are integrated into a microfluidic channel and operated in water using a rotating permanent magnet. 相似文献
102.
Jatinder S. Randhawa Kate E. Laflin Natasha Seelam David H. Gracias 《Advanced functional materials》2011,21(13):2395-2410
The development of microchemomechanical systems (MCMS) as an analogy to microelectromechanical systems (MEMS) is reviewed, with the distinction that the mechanical actuation of microscale structures is effected by chemical cues as opposed to electricity. The intellectual motivation to pursue MCMS, or the creation of integrated chemical‐stimuli‐responsive devices, is that such structures are widely observed in nature. From a practical standpoint, since chemicals can readily diffuse and produce changes over large distances, this approach is especially attractive in enabling wireless and autonomous devices at small size scales. 相似文献
103.
研究施加轴向压缩力于悬臂梁压电双晶片端部以增大端部输出位移和力的问题,对其进行了有限元分析,并推导了弹性力学解析解及模态方程,得到了符合程度较好的结果。研究结果表明,在120V电压及5.5N轴向力作用下,端部阻塞力达0.25N,输出位移较原来增大3倍以上(达5mm),而一阶特征频率随轴向力增大而加速减小。当轴向力达到一阶临界屈曲时,一阶特征频率趋于0,但当轴向力取一阶屈曲力的70%时,其1阶固有频率仍有45Hz,相较于普通伺服舵机有较大的优势,可有效提高微小型飞行器的操稳性。 相似文献
104.
Soft Robotics: Pneumatic Networks for Soft Robotics that Actuate Rapidly (Adv. Funct. Mater. 15/2014)
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105.
Relaxor/Ferroelectric Composites: A Solution in the Quest for Practically Viable Lead‐Free Incipient Piezoceramics
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Claudia Groh Daniel J. Franzbach Wook Jo Kyle G. Webber Jens Kling Ljubomira A. Schmitt Hans‐Joachim Kleebe Soon‐Jong Jeong Jae‐Shin Lee Jürgen Rödel 《Advanced functional materials》2014,24(3):356-362
Recently developed lead‐free incipient piezoceramics are promising candidates for off‐resonance actuator applications with their exceptionally large electromechanical strains. Their commercialization currently faces two major challenges: high electric field required for activating the large strains and large strain hysteresis. It is demonstrated that design of a relaxor/ferroelectric composite provides a highly effective way to resolve both challenges. Experimental results in conjunction with numerical simulations provide key parameters for the development of viable incipient piezoceramics. 相似文献
106.
Superparamagnetic Twist‐Type Actuators with Shape‐Independent Magnetic Properties and Surface Functionalization for Advanced Biomedical Applications
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Christian Peters Olgaç Ergeneman Pedro D. Wendel García Michelle Müller Salvador Pané Bradley J. Nelson Christofer Hierold 《Advanced functional materials》2014,24(33):5269-5276
Directed nanoparticle self‐organization and two‐photon polymerization are combined to enable three‐dimensional soft‐magnetic microactuators with complex shapes and shape‐independent magnetic properties. Based on the proposed approach, single and double twist‐type swimming microrobots with programmed magnetic anisotropy are demonstrated, and their swimming properties in DI‐water are characterized. The fabricated devices are actuated using weak rotating magnetic fields and are capable of performing wobble‐free corkscrew propulsion. Single twist‐type actuators possess an increase in surface area in excess of 150% over helical actuators with similar feature size without compromising the forward velocity of over one body length per second. A generic and facile combination of glycine grafting and subsequent protein immobilization exploits the actuator's increased surface area, providing for a swimming microrobotic platform with enhanced load capacity desirable for future biomedical applications. Successful surface modification is confirmed by FITC fluorescence. 相似文献
107.
Isabella S. Romero Nathan P. Bradshaw Jesse D. Larson Sean Y. Severt Sandra J. Roberts Morgan L. Schiller Janelle M. Leger Amanda R. Murphy 《Advanced functional materials》2014,24(25):3866-3873
Single‐component, metal‐free, biocompatible, electromechanical actuator devices are fabricated using a composite material composed of silk fibroin and poly(pyrrole) (PPy). Chemical modification techniques are developed to produce free‐standing films with a bilayer‐type structure, with unmodified silk on one side and an interpenetrating network (IPN) of silk and PPy on the other. The IPN formed between the silk and PPy prohibits delamination, resulting in a durable and fully biocompatible device. The electrochemical stability of these materials is investigated through cyclic voltammetry, and redox sensitivity to the presence of different anions is noted. Free‐end bending actuation performance and force generation within silk‐PPy composite films during oxidation and reduction in a biologically relevant environment are investigated in detail. These silk–PPy composites are stable to repeated actuation, and are able to generate forces comparable with natural muscle (>0.1 MPa), making them ideal candidates for interfacing with biological tissues. 相似文献
108.
Hanlin Lv Wan Zheng Yuhang Wang Zhengsheng Hu Yanjun Chen Yifeng Wang 《应用聚合物科学杂志》2024,141(19):e55339
Photonic crystal hydrogels are widely used in the field of visual detection, based on the response of the structural color to external stimulus, such as pH, temperature, near-infrared light, and so on. Here, we develop an opal photonic crystal hydrogel by combining polystyrene (PS) photonic crystals with a fluorescent double-network hydrogel and focus on both its visual detection function and mechanical property. The opal hydrogel is composed of nanocomposite hydrogel as the first network and ionic crosslinked hydrogel as the second network. The introduction of PS photonic crystals and terbium ions endows the opal hydrogel distinctive structural colors and fluorescence, respectively. Because of volume changes, the structural color of the opal hydrogel selectively responses to metal ions and organic solvents. Attributing to the ion exchange interaction, the opal hydrogel exhibits fluorescent responses to various metal ions. Combining the responsiveness of structural color and fluorescence, a visual dual-detection mode is set up, with better detection sensitivity and selectivity. Moreover, the characteristics of nanocomposite and double-network crosslinking ensure the opal hydrogel enough mechanical properties to undergo cycle visual detection. Consequently, the fabricated opal hydrogel is promising for use in visual detection to multiple substances in single- or dual-detection mode. 相似文献
109.
Dmitri Tcherniak 《International journal for numerical methods in engineering》2002,54(11):1605-1622
The present paper is concerned with the layout optimization of resonating actuators using topology optimization techniques. The goal of the optimization is a maximization of the magnitude of steady‐state vibrations for a given excitation frequency. The problem formulation includes an external viscous damper at the output port which models a working load on the structure. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
110.