Electrospinning Behaviors and Control Technologies for Direct-Writing Polymeric Micro/Nano-Structure

基于近场静电纺丝的电纺直写技术是利用稳定直线射流进行图案化微纳米结构的直接沉积，为聚合物微纳米结构的低成本可控制造及其应用开拓了一个新的途径。本文主要围绕电纺直写喷射与沉积行为、微纳米结构定位沉积和图案化制备控制等方面开展研究工作。 构建了精密直写平台，直写出了直径80~800nm的固态纳米纤维和线宽1~150μm的微米薄膜。分析了微纳米结构直径/线宽的变化规律；研究了纺丝射流喷射运动行为；讨论了收集板匹配运动速度的变化规律；考察了收集板导电率对纳米纤维沉积的作用行为，为电纺直写启停控制和微纳米结构尺寸的精确调控奠定了实验基础。 实现了近场条件下单股射流喷射过程纺丝电流的实时检测。根据纺丝...Straight stable jet is utilized to fabricate patterned polymeric micro/nano-structure directly in the direct-writing technology based on near-field electrospinning, which provides a novel way for the low cost controllable fabrication and application of polymeric micro/nano-structure. The direct-writing ejection deposition behaviors, addressable deposition and patterned fabrication of polymeric mic...学位：工学博士院系专业：物理与机电工程学院机电工程系_机械电子工程学号：1992008015048

新工科背景下《互换性与技术测量》教学模式改革研究

针对当前《互换性与技术测量》课程教学中存在的知识点相对独立、教学过程与工程应用存在较大脱节、难以满足"新工科"背景下课程与知识创新的要求等问题,文章以成果产出为导向,开展课程内容的分层与归类,引入知识模块进行知识梳理与教学组织的重构,实现知识讲授、小组讨论、动手实践等教学环节的有机融合,完成教学闭环,提升案例教学效果。此研究可以较好地推动课程与知识创新,具有较好的实践意义。厦门理工学院2016年度教育教学改革与建设项目（JGY201601

Air filtration performance of nanofibrous membranes electrospuned with different nanofiber diameters

使用静电纺丝的方法,制造出不同直径的纳米纤维薄膜,在低风速下进行空气过滤实验,建立初步分析模型,分析了纤维直径和过滤性能间的关系。实验表明,纳米纤维的直径和过滤效率并不是正比关系,而是在某个纤径尺寸范围存在这一个最优值。对于PM10颗粒,纤维直径分布在400~600nm范围内的纳米纤维薄膜的过滤效果较好。分析模型的建立将促进纳米纤维薄膜空气过滤研究。Nanofibrous membranes of different nanofiber diameters are manufactured from electrospinning for the air filtration experiments,which are set in a mode of low wind velocity.A tentative model of experiment analysis is built up to analyze the relationship between filtration performance and nanofiber diameter.The experiments show that the filtration efficiency is not in direct proportion to the nanofiber diameter,which will be the best when the nanofiber diameter is in a special range.Better filtration performance for PM10 particles will be achieved when the nanofiber diameter is within the range between 400nm and 600nm.This experiment model will certainly further the researches on air filtration performance of nanofibrous membranes.国家自然科学基金资助项目(No.50675184);; 广东工业大学校青年基金资助项目(No.062042

Surface Acoustic Wave Radio Frequency Identification Technology and Its Development

声表面波(SurfACE ACOuSTIC WAVE,SAW)是沿物体表面传播的、能量集中于表面附近的一种弹性波。基于SAW技术实现的射频识别(rAdIO frEQuEnCy IdEnTIfICATIOn,rfId)是应用现代电子学、声学、微电子工艺技术和雷达信号处理技术等的新成就,具有纯无源,阅读距离大,制造成本低,可在高温差、强电磁干扰等恶劣环境下工作等特点,可应用于交通运输、工农业生产制造及监测等各个领域。它是基于集成电路芯片rfId的重要技术补充,逐渐受到了业界的广泛关注。文中基于SAW-rfId的工作原理介绍了SAW-rfId的特点及优势,分析讨论了SAW标签的编码方式、发展状况及关键技术问题等。Surface acoustic wave(SAW) is an acoustic wave traveling along the surface of a material exhibiting elasticity,with most energy concentrated nearby the surface.SAW-based radio frequency identification(RFID) technology is a new achievement involving the modern electronics,acoustics,microelectronic process technology and radar signal processing technology,etc.It is characterized by full passivity,wide-reading range,low cost and can operate under harsh environments,such as high temperature difference,strong electromagnetic interference,etc.It can be used in transport and communications,industrial and agricultural manufacturing and monitoring,etc.As an important complement to the RFID based on integrated circuit chip,it gradually receives increasing attention.In this paper characteristics and advantages of SAW-RFID are introduced based on its operation principle,the encoding modes,development situation and the key technological problems of SAW tags are analyzed and discussed

Advances in Electrospinning Technology for Preparing Nanofibers

通过对近年来大量相关文献进行分析,在介绍最新静电纺丝技术的同时,归纳出静电纺丝技术制造纳米纤维发展的两个方向,即微观控制方向与宏观制造方向.指出微观方向发展主要集中在如何提高纳米线的定位精度与纤维均一性等微观指标的控制;宏观方向上将聚焦于如何提高纺丝效率以及丝线有序性收集等关键问题上,为静电纺丝技术进一步发展提供了新的思路.Based on the analysis of much related literature in recent years,it introduces some of the latest technologies.Meanwhile,it sums up the development of nano-fibers in the two directions,micro-direction and macro-direction.In the micro-direction,more studies will focus on improving positioning accuracy,micro-fiber uniformity and so on.In the maro-direction,spinning efficiency and orderly collection will be emphasized.This study provides a new way of thinking for further development of electrospinning technology.国家自然科学基金资助项目(E051005);广东省自然科学基金资助项目(S2011040004079);广东工业大学博士启动基金资助项目(113010);广东省引进创新科研团队资助;广东省微纳加工技术与装备重点实验室资

Fabrication of micro/nanometer-channel by Near-Field ElectroSpinning

Direct-written polymer micro/nanofiber from Near- Field ElectroSpinning (NFES) was utilized as shadow-mask to fabricate uniform micro/nanometer-channel. Both Single straight microfiber (line-width 2~10?? m) and nanofiber (diameter 200~800nm) were direct-written on the substrate with the NFES setup, and then 2-nm-thick titanium adhesive layer and 10-nm- thick gold layer were sputtered on the substrate successively. By the ultrasonication process in acetone and de-ionized water, the polymer fiber was removed and micro/nanometer-channel with gap width ranging from 7?? m to 700nm was formed. The fabrication process and related technical issues were also outlined in this work. The experimental results revealed that the micro/nanometer channel had a good uniformity, above 90% of the gap length value lied within the deviation range of ±3%. This simple and facile method can be used to define the uniform micro/nano channel for organic thin film transistors. submicron-gap electrode by using an electrospun single fiber as shadow-mask. This is a simple and cost-effective method, yet the nanofiber used as shadow-mask was obtained through the post-stretching process, which increased the complexity and uncertainty of fabrication process. In this paper, Direct-write (DW) technology (9) based on Near-Field ElectroSpinning (NFES) (10) was utilized to obtain single straight micro/nanofiber directly, and used as shadow- mask to fabricate micro/nanometer-channel. The gap length of micro/nanometer-channel was in the range of 700nm to 7?? m. The fabrication process and related technical issues were described, and then the uniformity of micro/nanometer-channel was also evaluated and discussed

Large-scale patterned nanofibers via tip-less electrospinning

Tip-less Electrospinning (TLES) process has been developed to produce polymer nanofibers with high throughput. And the ameliorated collector with parallel top-down configurations of two different materials in conventional electrospinning, such as polyethylene terephthalate (PET)-glass, copper-glass and PET-silicon etc, can achieve patterned nanofibers to expand its future applications. In this paper such patterned collectors array with changed electric field around, are introduced to TLES to deposit large-scale patterned nanofibers. The experiment results show that patterned nanofibers can be collected along the gap between plastic plates in both plastic-glass and plastic-silicon configuration. To the copper-glass collector, nanofibers bridge over the gap and the nanofiber quantity density on the gap is much less than that on the copper. But the patterned effects in all configurations are relatively weaker than that from foremetioned spinning due to their much higher speed, more serious bending instability and repulsive interactions between as-spun nanofibers

Bead-on-string structure formed by electrohydrodynamic printing

A Bead-on-String (B-S) structure which consists of droplet and filament is generated based on electrohydrodynamic printing system. The formation process of the B-S structure is demonstrated and discussed. Subsequently, the influence of the substrate moving speed on the B-S structure is investigated. The size of the droplet in the B-S structure decreases with the substrate moving speed. When the substrate moving speed is higher than the jetting speed, satellite droplet will appear and its number increases with the substrate moving speed. The effect of the solution concentration on the deposited patterns is also studied. A continuous line is printed with 3 wt% PEO solution. The B-S structure is generated when the concentration of the PEO solution is within 5-15 wt%. Moreover, the size of the droplet decreases with the increasing of the solution concentration. At the concentration of 18 wt%, nanofiber is produced and a pattern similar to the B-S structure is deposited on the substrate

Experiment on EHD Printing under DC High Voltage

基于直流电压作用下的电液耦合微喷印系统,考察了溶液浓度和电压两个参数对喷印过程和沉积形态的影响。实验结果表明射流在收集板上沉积的宽度随溶液浓度增大而减小;浓度低时射流沉积为连续形态;浓度增大,射流沉积为液滴-细线相间或者液滴-卫星液滴相间的珠状结构;浓度增大至18%时,产生纳米纤维,直径600nM左右。对给定的EHd实验系统,仅当电压值在2.6kV~4.8kV范围内变化时可保证稳定喷射;且随着电压值增大,珠状结构的直径减小;电压值在该范围之外,无法实现稳定喷射。Based on the EHD printing system under the DC high voltage,the influence of the concentration of solution and the voltage value on jetting process and the collected lines is investigated.Experimental results show that the collected line gets thinner with the concentration of solution increasing.The collected line is continuous at low concentration of solution.The bead form of a droplet with a filament or satellite droplets is collected with the concentration of solution increasing.At 18 % concentration of solution nanofibre with the diameter of 600nm is collected.For a given EHD printing system,when the voltage value is in the range of 2.6 kV ～ 4.8 kV,the jetting process is stable and the diameter of the bead decreases with the voltage value increasing.Outside this range,the stable jetting process can not happen.高等学校科技创新工程重大项目培育资金项目资助(708055);国家863项目资助(2007AA04Z308);国家自然科学基金项目资助(50675184

Design of pH Control System for Electrodialysis Water Treatment

电渗析技术以其独特优势,在水处理、食品和化工等领域有着广泛的应用。针对电渗析水处理系统出水酸碱度可调的应用需求,利用STM32F407RET6单片机开发了一套基于PID算法的pH值控制系统,运用PWM方式完成了电渗析电源电压的快速控制,实现电渗析水处理系统出水pH值的快速调节,调节时间小于30s。所述酸碱度控制系统的开发,有助于提升水处理系统的响应速度,提高水质监控水平。To meet the requirement of adjustable water pH for electrodialysis water treatment system,a pH value control system based on PID algorithm is developed using STM32F407RET6 microcontraller.Then to realize rapid water pH adjust- ment of the electrodialysis water treatment system,the PWM method is utilized for fast control of the electrodialysis power supply voltage,which makes the adjusting time less than 30s.The development of pH value control system contributes to im- proving the response speed of the water treatment system.国家自然科学基金（51405408）; 厦门南方海洋研究中心项目（15GHS019HJ03）; 厦门市科技计划项目（3502Z20163005）; 福建省中青年教师教育科研项目（JAT160002