具有刚性运动基的柔性结构振动主动控制

针对具有刚性运动基的柔性板结构的振动主动控制进行了研究。建立了包含压电机敏元件的、具有刚性转动体与二维柔性板的、刚柔耦合系统的振动数学模型;获得了系统的状态方程、传感方程与反馈控制方程,根据输出反馈控制原理,求得了反馈增益矩阵,在此基础上进行了实验研究,实验结果证明了理论研究的合理性和有效性。     

A Device-Level Vacuum-Packaging Scheme for Microbolometers on Rigid and Flexible Substrates

This paper reports on the design, fabrication, and characterization of device-level vacuum-packaged microbolometers on rigid Si wafers and flexible polyimide substrates. Semiconducting yttrium barium copper oxide (commonly referred to as YBCO) serves as the bolometric material. Operating micromachined bolometers in vacuum reduces the thermal conductance G_th from the detector to the substrate. If flexibility of the substrate is not to be sacrificed, then the vacuum packaging needs to be done at the device level. Here, the microbolometers are fabricated on a silicon nitride support membrane, isolated from the substrate using surface micromachining. Suitable materials as well as various dimensions in the vacuum cavity are determined using finite-element method (FEM)-based CoventorWARE. A vacuum cavity made of Al₂O₃ has been designed. The thermal conductance G_th of bolometers with the geometry implemented in this work is the same for devices on rigid and flexible substrates. The theoretical value of G_th was calculated to be 4.0 x 10^-6 W/K for devices operating in vacuum and 1.4 x 10^-4 W/K for devices operating at atmospheric pressure. Device-level vacuum-packaged microbolometers on both rigid Si and flexible polyimide substrates have been fabricated and characterized for optical and electrical properties. A low thermal conductance of 1.1 X 10^-6 W/K has been measured six months after fabrication, which implies an intact vacuum cavity.     

Self-Aligned, Extremely High Frequency III-V Metal-Oxide-Semiconductor Field-Effect Transistors on Rigid and Flexible Substrates

This paper reports the radio frequency (RF) performance of InAs nanomembrane transistors on both mechanically rigid and flexible substrates. We have employed a self-aligned device architecture by using a T-shaped gate structure to fabricate high performance InAs metal-oxide-semiconductor field-effect transistors (MOSFETs) with channel lengths down to 75 nm. RF measurements reveal that the InAs devices made on a silicon substrate exhibit a cutoff frequency (f(t)) of ～165 GHz, which is one of the best results achieved in III-V MOSFETs on silicon. Similarly, the devices fabricated on a bendable polyimide substrate provide a f(t) of ～105 GHz, representing the best performance achieved for transistors fabricated directly on mechanically flexible substrates. The results demonstrate the potential of III-V-on-insulator platform for extremely high-frequency (EHF) electronics on both conventional silicon and flexible substrates.     

刚体碰撞约束柔性体局部撞击载荷特征分析

目的 掌握碰撞局部撞击载荷及其特征,为产品安全防护设计、碰撞响应分析与评估提供理论基础。方法 抽象刚体碰撞柔性体的共性特征,分别将被撞击柔性体的碰撞局部刚度特性和整体结构效应表征为弹簧力-位移关系,建立系统的二自由度刚-柔碰撞动力学模型,应用数值方法系统分析刚柔碰撞局部撞击载荷的特征及不同因素的影响。结果 获得了刚体初始碰撞速度、柔性体碰撞局部刚度特性与整体结构效应等主要因素对局部撞击载荷时程、冲量、峰值和脉宽等撞击载荷特征的影响规律。结论 深化了刚-柔碰撞局部撞击载荷的认知,为防护结构设计提供了理论基础。     

A New Class of Materials: Sequence‐Defined Macromolecules and Their Emerging Applications

Emerging applications of a new class of materials, sequence‐defined macromolecules, are explored. Such molecularly highly defined macromolecules require stringent synthesis and purification procedures, yet offer unprecedented application possibilities. The first examples of molecular data storage and related technologies are already starting to emerge today. From a more fundamental point of view, such macromolecules offer a unique opportunity to determine quantitative structure–property relationships (QSPR), which critically aids in designing materials with applications ranging from catalysis to artificial enzymes.     

机器—基础动力耦合系统最优控制器设计与性能仿真

针对柔性基础上马达和仪器的主动隔振问题，建立了刚性机器-柔性基础动力耦合系统的状态空间方程。利用线性二次调节器理论，对耦合系统的振动功率流传递进行了最优控制。并对系统的瞬态响应与状态观测器构造等问题进行了研究。     

柔性联接对提高转子系统运动稳定性的作用

以柔性联接的两转子系统为研究对象,通过对其在冲击转矩作用下,旋转系统非线性运动方程的建立、求解,得到了转子冲击扭转振动响应的解析解.经过对转子冲击角加速度随线性刚度、阻尼和非线性刚度变化规律的仿真计算发现在相同初始条件下,冲击角加速度随柔性连接器阻尼的增大而减小;随柔性连接器扭转刚度的减小而减小;随柔性连接器硬非线性刚度的增大而增大,随柔性连接器软非线性刚度的增大而减小.说明可以通过调节柔性联接器的刚度和阻尼,提高旋转系统运动的稳定性.     

附加端子及其对智能机器人类型产品电磁兼容检测的适用性分析

讨论和分析了智能机器人类型产品进行电磁兼容检测的标准适用性问题。结合标准CISPR 14-1给出的限值和测试要求,描述了在电源端子和附加端子上进行传导骚扰测试的测量程序。分析了标准CISPR 14-1中对使用不同电源（供电网络供电,或者电池供电）要求的测试要求。使用某型号智能机器人产品分析了其附加端子的特征,讨论了如何对附加端子进行分类,并提供了对此类产品进行电磁兼容检测的规范流程。     

柔性透明基底上纳米银树枝结构的制备及光学特行

采用化学电沉积方法,通过调节沉积电压、沉积时间等电沉积条件,在氧化铟锡(ITO)柔性透明导电薄膜基底上制备二维纳米银树枝.并在其表面电沉积一定厚度的绝缘薄膜后与另外一层二维纳米银树枝叠合组装成银树枝、绝缘薄膜和银树枝的"三明治"复合材料.实验表明,该"三明治"复合材料在可见光频段380～800nm处有多个吸收峰,这种特殊的光透射行为可能是由光波在复合材料中的电磁响应引起的.     

基于银纳米颗粒墨水在柔性基材表面制备导电薄膜及其电阻率

通过两相界面反应制备出小尺寸银纳米颗粒,用喷墨打印技术和热处理工艺在柔性PET基材表面制备导电薄膜。用紫外-可见光吸收光谱、透射电镜和能谱研究了银颗粒粒径、微结构和成分,结果表明所合成的颗粒为多晶结构,粒径为2～5nm。用扫描电镜和四探针薄膜电阻率测量法研究了热处理温度、时间与薄膜形貌、电阻率之间的关系,结果表明柔性PET塑料表面的银颗粒在150℃条件下处理30min,可获得表面平整、无明显裂纹、电阻率～6.4μΩ.cm的导电薄膜。     

三乙醇胺助磨剂对水泥与聚羧酸系减水剂适应性的影响及其机理

测试了以三乙醇胺(Triethanolamine,TEA)为助磨剂所磨制的水泥(TEA-C)的基本物理性质,探究了TEA-C与聚羧酸系减水剂(Polycarboxylate superplasticizer,PCE)体系浆体流动性及经时流动性的变化规律,并通过吸附量测定、水化热分析、TEA溶出量测试分析以及水泥颗粒表面性质分析等方法揭示了TEA的助磨机理及其对水泥与PCE适应性的影响机理。结果表明,TEA作为助磨剂使用时,当其掺量为0%~0.02%时,所磨制的水泥与PCE适应性良好,其原因为少量的TEA改善了水泥颗粒的粒径分布;当其掺量为0.02%~0.04%时,TEA-C与PCE出现适应性不良的现象,其原因为PCE吸附量降低,水泥水化速率加快。     

柔性驱动对转子碰摩运动特性的影响

建立了柔性驱动转子系统的动力学方程，通过求解方程得到了柔性驱动器的扭转响应和转子与定子碰摩后的冲击角加速度响应。讨论分析了柔性驱动在控制转子碰摩运动中的作用，发现转子的冲击角加速度随柔性驱动器扭转刚度的增大而增大，随柔性驱动器扭转刚度的减小而减小，说明在转子系统其他参数不变的情况下，可通过调整柔性驱动器的扭转刚度以达到提高转子运动稳定性的目的。     

熟料煅烧气氛对水泥与减水剂相容性的影响

采用Marsh筒法研究了还原气氛与正常气氛条件下煅烧熟料磨制水泥与减水剂的相容性,并通过XRD与岩相分析法研究了熟料的矿物组成与矿物形态,揭示了煅烧气氛对水泥与减水剂相容性影响的内在原因.结果表明,还原气氛条件下,熟料中三价铁被还原,形成钙铁橄榄石(CaO·FeO·SiO2)类矿物,使C4AF含量减少,原本可固溶在C4AF矿物中的部分氧化铝也随之减少,从而增加了C3A的实际含量;且熟料结粒粗大,升重较高,冷却效果较差,造成C3A大量析晶,导致水泥与减水剂的饱和点增大,流动性经时损失变大,相容性显著变差.     

沙发靠背架上弹性材料对坐姿舒适度影响的研究

本文以沙发靠背框架上的弹性材料即靠筋和蛇形弹簧为研究对象,结合主观评价,利用体压分布测试的方法,分析了靠背框架上弹性材料对人体坐姿舒适度的影响。研究结果表明,框架上的弹性材料对坐姿舒适度有着重要的影响,可以通过提高其弹性来提高坐姿的舒适度。     

16.67% Rigid and 14.06% Flexible Organic Solar Cells Enabled by Ternary Heterojunction Strategy

Ternary heterojunction strategies appear to be an efficient approach to improve the efficiency of organic solar cells (OSCs) through harvesting more sunlight. Ternary OSCs are fabricated by employing wide bandgap polymer donor (PM6), narrow bandgap nonfullerene acceptor (Y6), and PC₇₁BM as the third component to tune the light absorption and morphologies of the blend films. A record power conversion efficiency (PCE) of 16.67% (certified as 16.0%) on rigid substrate is achieved in an optimized PM6:Y6:PC₇₁BM blend ratio of 1:1:0.2. The introduction of PC₇₁BM endows the blend with enhanced absorption in the range of 300–500 nm and optimises interpenetrating morphologies to promote photogenerated charge dissociation and extraction. More importantly, a PCE of 14.06% for flexible ITO‐free ternary OSCs is obtained based on this ternary heterojunction system, which is the highest PCE reported for flexible state‐of‐the‐art OSCs. A very promising ternary heterojunction strategy to develop highly efficient rigid and flexible OSCs is presented.     

刚柔耦合列车半主动悬挂参数自调整模糊控制

为抑制刚柔耦合列车模型车体横向振动,在ANSYS中建立车体有限元模型并将模态中性文件导入ADAMS/Rail,建立考虑车体横向弹性振动的刚柔耦合列车动力学模型,分析弹性振动对车体运行平稳性的影响。提出以车体前后两端横向振动加速度为反馈,采用参数自调整模糊控制对车体前后横向加速度进行双闭环独立控制。联合仿真结果表明,柔性车体的横向振动显著大于刚性车体的横向振动,通过必要的半主动参数自调整模糊控制,有效的降低车体横向振动,获得相比于普通模糊控制更优的控制效果。