多晶硅热驱动微执行器的热流模型及数值模拟

首先建立了一个横向热驱动微执行器的热流模型。由于这个模型比较全面地考虑了热传导、空气自然对流和辐射散热等各种因素 ,因而较为正确地反映器件的温度分布。用合适的数值算法计算了温度分布 ,温度分布的结果可以作为进一步计算器件热应力和位移的基础。最后 ,根据模拟结果分析了一些对温度分布产生影响的因素     

Prototype Fabrication and Preliminary In Vitro Testing of a Shape Memory Endovascular Thrombectomy Device

An electromechanical microactuator comprised of shape memory polymer (SMP) and shape memory nickel-titanium alloy (nitinol) was developed and used in an endovascular thrombectomy device prototype. The microactuator maintains a straight rod shape until an applied current induces electro-resistive (Joule) heating, causing the microactuator to transform into a corkscrew shape. The straight-to-corkscrew transformation geometry was chosen to permit endovascular delivery through (straight form) and retrieval of (corkscrew form) a stroke-causing thrombus (blood clot) in the brain. Thermal imaging of the microactuator during actuation in air indicated that the steady-state temperature rise caused by Joule heating varied quadratically with applied current and that actuation occurred near the glass transition temperature of the SMP (86degC). To demonstrate clinical application, the device was used to retrieve a blood clot in a water-filled silicone neurovascular model. Numerical modeling of the heat transfer to the surrounding blood and associated thermal effects on the adjacent artery potentially encountered during clinical use suggested that any thermal damage would likely be confined to localized areas where the microactuator was touching the artery wall. This shape memory mechanical thrombectomy device is a promising tool for treating ischemic stroke without the need for infusion of clot-dissolving drugs.     

Prototype fabrication and preliminary in vitro testing of a shape memory endovascular thrombectomy device.

An electromechanical microactuator comprised of shape memory polymer (SMP) and shape memory nickel-titanium alloy (nitinol) was developed and used in an endovascular thrombectomy device prototype. The microactuator maintains a straight rod shape until an applied current induces electro-resistive (Joule) heating, causing the microactuator to transform into a corkscrew shape. The straight-to-corkscrew transformation geometry was chosen to permit endovascular delivery through (straight form) and retrieval of (corkscrew form) a stroke-causing thrombus (blood clot) in the brain. Thermal imaging of the microactuator during actuation in air indicated that the steady-state temperature rise caused by Joule heating varied quadratically with applied current and that actuation occurred near the glass transition temperature of the SMP (86 degrees C). To demonstrate clinical application, the device was used to retrieve a blood clot in a water-filled silicone neurovascular model. Numerical modeling of the heat transfer to the surrounding blood and associated thermal effects on the adjacent artery potentially encountered during clinical use suggested that any thermal damage would likely be confined to localized areas where the microactuator was touching the artery wall. This shape memory mechanical thrombectomy device is a promising tool for treating ischemic stroke without the need for infusion of clot-dissolving drugs.     

平板显示器制造中用作精密淀积设备的喷墨印刷头

显示器设备制造商之间有着共同的发展计划,电子流体显色剂和喷墨印刷头的设计者们已成功实现了大型电子显示板平板显示器引导线制造中特制的喷墨印刷头的发展计划。这种喷墨印刷头正在被认作各种大面积液晶显示器制造工艺的精密淀积设备。现这种喷墨型设备的市场需求正在不断增长。对于通过单独整理每个喷嘴通道进行一个128喷嘴的压力式喷墨印刷头流体下降位置控制情况给予了介绍。这种印刷头用作大型电子显示板显示器引导线的制造,通过采用不同的印刷头便可使大面积衬底的生产率得到提高的机会。讨论了通过印刷头和系统设计提高生产率实质。其它的高技术市场为利用精密降落位置和降落量控制。并给出了采用喷嘴制作印刷电路极的一些例子。     

TiNi／Si复合膜微驱动器原理及结构参数优化

应用有限元方法对TiNi/Si复合膜微驱动器的结构设计进行了分析，因TiNi和Si之间的热膨胀系数差别很大，溅射在Si(100)衬底上的TiNi膜，当从晶化的高温降下来时会积聚很大的热应力，这种微驱动器，就是利用了TiNi的形状记忆效应而引起的这些应力的释放与恢复从而引起复合膜的振动，图形化TiNi薄膜制成加热电阻条件为自加热电阻，可降低功耗，提高响应速度，简化结构， 但作为驱动单元的一部分，其图形化的结构参数对复合膜的挠度有很大的影响，通过结构参数优化，可使复合膜的中心挠度值达到最大，从而提高驱动器的性能。     

有机电致发光器件中有机薄膜的制备方法

有机电致发光器件中有机薄膜的制备方法非常重要,不同方法制备的薄膜质量不同,这直接影响着器件的效率;制备方法直接影响到产业化中的器件制备成本。根据材料的不同,有机小分子常用真空蒸镀的方法,而高分子材料常用旋涂的方法制备薄膜。随着有机电致发光器件制备工艺的发展,相继出现了其他的制备工艺,如:有机蒸汽喷印(organic vapor jet printing)、有机气相沉积(organic vapor phase deposition)、丝网印刷(screen printing)和喷墨打印(ink jet printing)技术等,这对有机电致发光显示器产业化发展具有巨大的推动作用。文章综述了这些制备方法,比较了它们的优缺点,以及这些工艺对产业化的影响。     

A magnetically driven linear microactuator with new driving method

Electromagnetically driven microactuators are of interest because they have the potential to generate large deflections. Thus, we have been studying magnetically driven microactuators. This time, a magnetically driven linear microactuator has been newly developed by using microfabrication techniques. The microactuator is composed of a mobile microplatform (mover) with some permanent magnets (PMs) and a stator with a large number of planar coils. In this paper, two types of microplatforms are fabricated and compared with each other. Furthermore, static and dynamic characteristics of the magnetically driven linear microactuator are discussed.     

基于PCB定位圆孔边缘检测技术研究

通信、计算机、消费电子等产业飞速发展,促进了印制电路板(PCB)的快速发展。同时,低碳、环保的要求使PCB行业面临着巨大的挑战。开发高效、低耗、节能、环保的PCB生产技术必定成为主流工艺技术。为此,我公司研制喷墨设备。文章是以我公司研发喷墨设备影像定位系统中检测定位孔为应用背景,介绍Sobel、Prewitt、Roberts、Laplace与Canny边缘检测算子,并用五种算子对大量PCB定位孔(工艺组设计)边缘检测,结合圆孔定位实际检测与喷印成功率对比优缺点,确定Canny算子是本应用中PCB定位圆孔边缘检测的最优算子。     

Full Color Light Responsive Diarylethene Inks for Reusable Paper

“Digitalization” represents one approach to shift society's dependence on paper‐based communication. However, thus far, this tactic has not had a significant impact on global paper consumption, which has risen over the past few decades. The escalating demand of paper making and consumption has resulted in an intensified negative effect on the environment. Because of this, the development of rewritable paper or erasable ink appears to be an ideal approach to alleviate the increasing demand for paper. In the investigation described herein, novel light‐stimulated (UV–vis), reversible color switching, photochromic diarylethene (DE) derivatives are designed, which serve as cyan, magenta, and yellow colored ink materials for full color ink‐jet printing. The structures of the DE derivatives are unique in that they contain hydrophilic ethylene glycol chains that enable them to be compatible with aqueous based, ink‐jet printing systems. The results of these studies demonstrate that the new DE derivatives can be used in a printing system based on the “write–erase–write” concept that utilizes the same paper multiple times. The approach appears to be ideal for reducing the negative environmental consequences of paper production and consumption.     

压电驱动微型喷雾器的研究

研究开发了一种压电驱动微型喷雾器。利用微机械加工技术,制作微米级的喷孔阵列,基于喷墨打印机原理,微喷换能器采用压电驱动方式在其较高阶谐振状态下工作。实验分析了这种微喷换能器的阻抗特性、谐振状态下振动特性以及微型喷雾器的工作性能。实验结果表明,这种喷雾器喷出的雾滴直径大小集中,工作稳定且容易控制喷雾量。     

Thermal ink jet technology

Micromachining and microelectromechanical system (MEMS) technology have enabled the unprecedented cost/performance ratio of thermal ink jet (TIJ) products that currently dominate the desktop color printing market. The generic TIJ operating principles are based on an intimate blend of thermodynamics, fluid dynamics, and large-scale integration (LSI) electronics. This article introduces the generic operating principles and design issues of TIJs, and the fabrication of TIJ printheads is illustrated with an implementation by the Xerox Corporation     

气溶胶喷墨打印在有机器件制备中的应用

气溶胶喷墨打印是近年来新出现的一种打印技术。通过将形成的墨水气溶胶喷射至基底表面而成膜,使得气溶胶喷墨打印对墨水的黏度要求低、打印分辨率好、适用墨水的范围广。文章对气溶胶喷墨打印技术的基本原理、在有机器件制备方面的应用以及将来的改进等方面进行了简介和评价。     

基于红外指纹光谱的快速鉴别黑色记号笔墨水

为了实现对记号笔墨水的检验与认定，采集了广博等5种品牌共计40支黑色记号笔红外指纹图谱数据。采用了多元散射校正、峰面积归一化、自动基线校正和Savitzky-Golay平滑等技术，建立了基于多层感知器的黑色记号笔墨水分类模型，进行了理论分析和实验验证。结果表明，红外指纹图谱能反映分子结构的细微变化，可将水性与油性记号笔区分; 针对4种油性记号笔样本，发现模型在30维矩阵上特征提取最好，准确率为100%, 其中特征12、特征26和特征17对模型区分效果的贡献程度最高，分别为0.0355, 0.0347和0.0346;4种油性品牌记号笔样本均实现了100%的准确区分, 其中乐途品牌样本聚敛程度较高，分布集中，其墨水组分和含量差异较小，宝克品牌样本分布较为分散，其墨水组分和含量相对差异较大; 在验证性分析中，8个待判定样本均实现了100%的准确区分和归类，实验结果理想，利用红外指纹图谱结合多层感知器可实现黑色记号笔墨水品牌间的准确识别与分类。该方法提高了检验鉴定效率、降低了检验鉴定成本、可满足一线执法人员快速、准确的检验需求。研究结果具有一定的普适性和借鉴意义。     

Controlling the Thickness of the Surface Oxide Layer on Cu Nanoparticles for the Fabrication of Conductive Structures by Ink‐Jet Printing

With the aim of preparing a high performance conductive ink, we sought to control the surface chemistry of Cu nanoparticles so as to minimize surface oxidation. Specifically, the surface oxide layer on Cu nanoparticles synthesized in ambient atmosphere was minimized by adjusting the molecular weight of poly(N‐vinylpyrrolidone) capping molecules, as confirmed by high resolution transmission electron microscopy and X‐ray photoelectron spectroscopy analyses. In addition, we demonstrate that by minimizing the thickness of the surface oxide layer, Cu granular films with good conductivity could be obtained by sintering nanoparticle assembles. Finally, we fabricated highly conductive Cu patterns on a plastic substrate by ink‐jet printing.     

红外光谱结合化学计量学检验直液式走珠笔墨水

检验鉴定书写墨水是法庭科学领域中一项重要的工作。利用傅里叶变换红外光谱仪对市面上常见的20种直液式走珠笔墨水样品进行检验,采取化学计量学实现了对直液式走珠笔墨水的快速检验。对傅里叶变换红外光谱数据做标准化处理,采取自动基线矫正、峰面积归一化、Savitzky-Golay 5点平滑3种方法对谱图做预处理,通过误差平方和指标（sum of the squares errors, SSE）确定分类K的最优取值,对样品进行K-均值聚类分析并解释聚类结果。采取主成分分析方法验证K-均值聚类的结果,利用组均值均等检验考察主成分变量对Fisher判别分析（Fisher discriminant analysis, FDA）模型的贡献程度,构建直液式走珠笔墨水的FDA判别模型。结果表明,K-均值聚类将全部墨水样本聚类为3类,PCA-FDA（principal components analysis-fisher discriminant analysis）模型能够对不同类别直液式走珠笔墨水达到100%的预测分类,经交叉验证后正确率达到100%。红外光谱与PCA-FDA模型结合可用于直液式走珠笔墨水的快速、准确检验鉴定。     

Thermal dissolution ink transfer for full-color printing

A thermal dissolution ink-transfer printing (TDIP) method for full-color image reproduction was developed. The TDIP method employs a thermo-melting ink sheet, a thermal head, and synthetic acceptor paper. The acceptor paper can hold a solvent in the many minute pores on its surface. The TDIP operates by dissolving the ink with the solvent. The amount of ink dissolved is controlled by the modulation of energy applied to the thermal head. The printing energy for each color of the TDIP was 1 J/cm². It was possible to obtain a high-quality full-color image by triple overlay printing of yellow, magenta, and cyan colored ink layers     

Silicon charge electrode array for ink jet printing

A monolithic charge electrode array suitable for use in a multiple channel ink jet printing apparatus has been fabricated by anisotropic etching of trapezoidal slots through a     

排放口结构对水下航行器热射流红外特征的影响

水下航行器动力系统循环冷却水经由排放口排出,与环境水体掺混换热形成热射流。热射流在环境水体中扩散、浮升并在水体表面形成红外特征。为探究排放口结构对水下航行器热射流红外特征的影响,文中采用仿真分析结合实验验证的方法进行研究。依托CFD计算软件平台建立水下航行器运动模型,设计不同半径比椭圆形排放口结构并对比热射流红外特征差异。通过缩比水池实验验证椭圆形排放口半径比对热射流红外特征的影响,同时验证仿真计算方法及设计参数的有效性。在椭圆形排放口的基础上,进一步设计排放口数量及分布位置,抑制热射流红外特征,提升水下航行器热隐身性能。根据仿真计算及实验结果可知,在排放流量相同的条件下,半径比越小的椭圆形排放口热射流掺混换热效果越好,红外特征越不明显。同时,增加排放口数量以及排放口分布位置采用两翼排列方式可以进一步加强热射流温度衰减,降低水面最高峰值温度。     

Self‐Organization of Ink‐jet‐Printed Triisopropylsilylethynyl Pentacene via Evaporation‐Induced Flows in a Drying Droplet

We have demonstrated the influence of evaporation‐induced flow in a single droplet on the crystalline microstructure and film morphology of an ink‐jet‐printed organic semiconductor, 6,13‐bis((triisopropylsilylethynyl) pentacene (TIPS_PEN), by varying the composition of the solvent mixture. The ringlike deposits induced by outward convective flow in the droplets have a randomly oriented crystalline structure. The addition of dichlorobenzene as an evaporation control agent results in a homogeneous film morphology due to slow evaporation, but the molecular orientation of the film is undesirable in that it is similar to that of the ring‐deposited films. However, self‐aligned TIPS_PEN crystals with highly ordered crystalline structures were successfully produced when dodecane was added. Dodecane has a high boiling point and a low surface tension, and its addition to the solvent results in a recirculation flow in the droplets that is induced by a Marangoni flow (surface‐tension‐driven flow), which arises during the drying processes in the direction opposite to the convective flow. The field‐effect transistors fabricated with these self‐aligned crystals via ink‐jet printing exhibit significantly improved performance with an average effective field‐effect mobility of 0.12 cm² V^–1 s^–1. These results demonstrate that with the choice of appropriate solvent ink‐jet printing is an excellent method for the production of organic semiconductor films with uniform morphology and desired molecular orientation for the direct‐write fabrication of high‐performance organic electronics.     

柔性膜式微型电磁驱动器的设计与仿真分析

硅橡胶具有生物兼容性好且制作技术与微细加工工艺兼容的优点,采用硅橡胶作为MEMS驱动器中的振动膜具有较好的应用前景。研究了一种微型电磁驱动器,由内嵌永磁体阵列的柔性硅橡胶(PDMS)振动膜和线圈两层构成,采用电镀工艺制作线圈层;采用电镀方法制作磁体阵列,由甩胶机旋涂硅橡胶并进行固化,制作内嵌磁体阵列的硅橡胶膜,对磁体磁化后可作为双向驱动器。对该驱动器进行了理论分析与数值模拟,采用有限元分析工具ANSYS对微驱动器的电磁驱动力及其挠度进行分析,二者结果基本一致,振动膜中心最大挠度的分析误差为7.96%,其一阶固有频率的分析误差为16.1%。