微透镜阵列防伪膜制备的新方法

基于微透镜阵列的防伪膜技术便于观察和易于识别的特点,采用高感光度的AZ 1500和较高解像度的AZ MIR-703正性光刻胶以及SU-8负性光刻胶对微透镜阵列防伪膜进行制备,光刻胶热熔法被用来制作微透镜阵列,PDMS被用来制作微透镜阵列的倒模,将SU-8和PDMS倒模配合使用制作最终的微透镜阵列,利用AZ 1500光刻胶制备微缩文字阵列,从而得到具有体视效果的微透镜阵列防伪膜。实验表征和分析表明,这种方法制备的微透镜阵列防伪膜效果明显,均匀性好。该方法与其他方法相比,工艺简单,对材料和设备的要求不高,工艺参数稳定易于控制,是一种微透镜阵列防伪膜制备的简便新方法。     

Liquid droplet as efficient master in thin membrane fabrication of poly(dimethylsiloxane) microfluidic devices

In this paper,liquid droplet master was for the first time used to fabricate thin membranes integrated polymeric microfluidic devices.As demonstration,water liquid droplet master was used to make a thin membrane in PDMS microfluidic devices which were prepared by using printed master.The PDMS membrane can be controlled down to approximately 10 μm thick with considerable vapour permeation which was adjusted by environmental humidity.An array of the microfluidic devices with thin PDMS membranes was also used ...     

Fabrication of high aspect ratio microfiber arrays that mimic gecko foot hairs

In nature, geckos have developed complex adhesion structures capable of smart adhesion, which is the ability to cling to different smooth and rough surfaces, even ceilings, and detach at will. The hierarchical structure of gecko foot hairs consists of microscale setae, branches and nanoscale spatulae, which contributes to their strong adhesion on different surfaces. In this paper, we propose a simple and low-cost method for fabricating two-level high aspect ratio microfiber arrays that mimic gecko foot hairs. SU-8 photoresist was used and single-level SU-8 microfiber arrays were obtained by a thick film photolithography process. Single-level polydimethyl-siloxane (PDMS) microfiber arrays were also obtained by a micromolding process and the master template for this process was fabricated using inductively coupled plasma (ICP) technology. Using the silicon mold with deep-hole arrays as a substrate, an SU-8 layer with microhole arrays was added to it using thick film photolithography and it formed a double stack mold from which the two-level hierarchical PDMS microfiber arrays were replicated. Water contact angle tests showed that the two-level hierarchical structures are extremely hydrophobic (about 148.5° compared with the Tokay gecko’s 160°).     

一种双腔体二甲基硅氧烷液体变焦透镜

针对PDMS(二甲基硅氧烷)液体变焦透镜在使用过程中常会发生边缘脱落从而影响透镜性能甚至毁坏整个器件的问题,提出了一种基于单点金刚石切削和软刻蚀工艺的双腔体可调焦透镜模型,该模型相比仅由单PDMS腔体和PDMS薄膜粘合的结构,能有效防止在大变形条件下变形膜边缘脱落,从而更大可能地保证透镜正常工作.测试结果表明:相比于单腔体的模型,该透镜在保留可调焦透镜性能的同时,具有更好的工作稳定性.     

Fabrication technology of integrated fiber microfluidic electrophoresis chip

The technology of PCB was used to fabricate the chip mould, and the microfluidic electrophoresis chip was fabricated with PDMS material. The fiber integrated on the chip was used as the transmission medium, so the light spot size was near the depth of microchannel. The detection sensitivity was improved, and the optical focusing system was spared. The fabrication process, sealing methods and structure characteristic of PDMS microfluidic electrophoresis chips were discussed. The experiment was achieved by using the fabricated chip to separate FITC fluorescein and FITC-labeled amino acid mixture reagent, and the feasibility of the chip was validated.     

混沌激光器阵列中斑图的形成与冻结

为了研究混沌激光器阵列中激光器同步行为,采用计算机数值模拟方法,对固定边界条件下的二维Lorenz-Haken激光器阵列进行了研究,发现激光器在空间上呈现出了丰富的斑图现象.实验结果表明,不同斑图的形成与激光器阵列数目大小N、激光器间耦合强度α有关.当混沌激光器阵列数目N固定时,随着激光器阵列间耦合强度的增加,激光器阵列在空间上出现的斑图依次呈现为空间无序、空间轴对称、空间中心对称状态,最终被冻结到不同的固定点,仍呈中心对称状态和空间轴对称和空间中心对称和冻结所对应的临界耦合强度αc随着激光器阵列数目大小N的增加而增加.     

A reversible wet/dry adhesive inspired by mussels and geckos

The adhesive strategy of the gecko relies on foot pads composed of specialized keratinous foot-hairs called setae, which are subdivided into terminal spatulae of approximately 200 nm (ref. 1). Contact between the gecko foot and an opposing surface generates adhesive forces that are sufficient to allow the gecko to cling onto vertical and even inverted surfaces. Although strong, the adhesion is temporary, permitting rapid detachment and reattachment of the gecko foot during locomotion. Researchers have attempted to capture these properties of gecko adhesive in synthetic mimics with nanoscale surface features reminiscent of setae; however, maintenance of adhesive performance over many cycles has been elusive, and gecko adhesion is greatly diminished upon full immersion in water. Here we report a hybrid biologically inspired adhesive consisting of an array of nanofabricated polymer pillars coated with a thin layer of a synthetic polymer that mimics the wet adhesive proteins found in mussel holdfasts. Wet adhesion of the nanostructured polymer pillar arrays increased nearly 15-fold when coated with mussel-mimetic polymer. The system maintains its adhesive performance for over a thousand contact cycles in both dry and wet environments. This hybrid adhesive, which combines the salient design elements of both gecko and mussel adhesives, should be useful for reversible attachment to a variety of surfaces in any environment.     

Cellulase Activities and Finishing Effects on Cotton Fabrics

The relationships between cellulase activities and theproperties of treated labrics including weight loss,breaking strength,surface thickness and bending rigiditywere investigated.Three cellulases were used to treattwo kinds of cotton fabrics and the results were com-pared to their activities measured towards filter paper,CMC and dewaxed cotton.The results suggested thatamong the three activities,exo activity(measured to-wards dewaxed cotton)be mostly inclined to reflect theactual hydrolytic capability of the cellulase on cotton fab-rics,while endo activity(measured towards CMC)wasof little use in predicting cellulase efflciency in terms ofweight loss.The investigation also suggested that the rel-atively endo-rich cellulase(Cellusoft Plus)was inclinedto give biopolishing effects by cleaning the surface fibrilof fabrics while the exo-rich cellulase(Cellusoft L,alsoknown as total or full cellulase)tended to deliver soften-ing cffects by decreasing the bending and shearing prop-erties.     

基于ITO玻璃-PDMS复合式低电压电泳芯片的快速制备

提出了一种基于ITO玻璃-PDMS复合式低电压电泳芯片的快速制备新方法.该方法采用Protel软件绘制低电压电泳芯片沟道的形状,利用电路板加工技术加工沟道模具,并采用PDMS整体浇注方法制备芯片微沟道;采用光刻、湿法刻蚀等微加工技术方法对ITO导电玻璃进行加工,并制备出ITO阵列电极.最后经修饰、封装等工序得到基于ITO玻璃-PDMS复合式低电压电泳芯片.实验表明:采用该方法制备的ITO阵列电极线条清晰,沟道侧壁陡直、表面光滑.同时,采用该方法制备芯片周期短,不需要昂贵的制作设备.     

UV-LIGA与微细电火花加工组合制造微细电解阵列电极

采用UV-LIGA与微细电火花加工组合技术制造大长径比微细阵列电极.先通过UV-LI-GA技术制作微细群孔工具电极,然后通过电火花套料加工制作大长径比微细阵列电极.选取优化的工艺参数:前烘110℃保持12h;三步后烘50℃保持5min、70℃保持10min、90℃保持30min;采用谐振式电火花电源,电压200V、峰值电流1.5A、脉宽3.2μs、脉间6.4μs、放电间隙12μm等,制备了直径85μm、长1.5mm,长径比达17.65的微细阵列电极.最后用制作出的微细阵列电极作为工具电极进行微细电解加工实验,在120μm厚不锈钢板上电解加工出直径150μm、形状均匀的微细阵列群孔结构.实验证明:UV-LIGA与微细电加工组合制造技术是一种可行的制作高深宽比微结构的方法;利用微细阵列电极进行电解加工,能实现高效和高精度加工.     

载药金属微针的结构设计及制备

摘要：
提出一种新型载药微针结构设计方案,采用硅的各向异性刻蚀工艺与SU 8胶光刻工艺相结合的方法制备硅与光刻胶复合载药微针模具,将硅的各向异性刻蚀所得棱锥结构用于复制微针的尖端部分,SU 8胶曝光套刻出的带凸起结构的柱体用于复制微针的柱体部分,以此微结构为模具,通过2次聚二甲基硅氧烷（PDMS）浇铸复制而得PDMS凹三维结构.在此结构上,溅射金属种子层后采用小电流电铸技术电镀金属Ni,脱模得到载药金属微针.经力学性能测试,其断裂强度为366 MPa,远大于刺穿皮肤所需断裂强度3.183 MPa. 关键词：
微针; 光刻胶; 各向异性刻蚀; 断裂强度 中图分类号： TN 302
文献标志码： A     

自主虚拟人真实感行为与运动建模的研究

提出一种采用微流控芯片进行微量液体表面张力系数测量的新方法,并对其制作工艺流程进行研究.以聚碳酸酯核孔膜为模,利用毛细作用力使聚二甲基硅氧烷预聚物充满膜孔.固化后与微腔室键合,注入有机溶剂溶模释放出微柱阵列.位于液气分界面处的微柱顶端由于蒸发作用打破表面张力平衡引起微柱发生弯曲形变,通过对微柱形变图像处理,计算得出表面张力系数.实验结果表明该测量方法有效,测量精度达到nN/μm.     

Poly(dimethylsiloxane) based microchip for DNA electrophoresis

A novel poly(dimethylsiloxane)(PDMS) -based microchip for DNA separation through electrophoresis has been developed using a micro-electro-mechanical-system(MEMS) technology. Unlike previous hybrid PDMS microchip, one PDMS film is first created on glass support by pressing method in our microchip. Thus, increased band-broadening phenomena, arising from the material nonuniformity at the walls of microchannel, can be avoided in electrophoresis process. A low-viscosity hydroxypropylmethylcellulose-100 (HPMC-100) is used as the separation medium for fluorescent intercalator-labeled double-stranded DNA (dsDNA) fragments. Mannitol is introduced to PDMS-based microchip as a separation medium additive to enhance separation efficiency. At applied electric field strength of 150 V/cm, excellent separations of the PCR marker could be achieved with an effective separation distance of 25mm .     

氨基硅油改性聚氨酯的合成及性质

Multi-phase segmented siloxane-urethane copolymers have been reported in the literature which were prepared by primary or secondary amine terminated siloxane oligomers with diisocyanates and diols. However, because of the introduction of PDMS into the main chain of     

柔性微热剪切应力传感器阵列 

设计了一种基于微机电系统的、制备在柔性聚酰亚胺衬底上的双热线结构微型热剪切应力传感器阵列,可用于复杂形状物体表面所受剪切应力的矢量化测量.基于传感器的原理,用Comsol软件对传感器进行了温度场和流场的仿真,说明了传感器制作工艺流程,用硅橡胶与聚酰亚胺在酒精中浸泡后易于剥离的特点实现柔性传感器脱膜.对传感器实物进行了温度电阻系数和响应频率的测试.实验结果表明,设计的工艺路线简单,结构参数合理,可以实现所需柔性传感器阵列.
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Morphology and contact mechanics influence adhesive characteristics of Dung Beetle’s bristle and Gecko’s setae

Geckos(Gekko gecko)use their hairy setae to adhere on various solid surfaces and dung beetles(Copris ochus Motschulsky)use their hairy bristles to anti-adhere in sticky environments.We study why two hairy systems express a conflict in functions by using SEM,histological approaches and functional experiments.Adhesion models and various parameters were collected and analyzed.Based on the morphological data and functional experimental results carried out by natural and denatured gecko setae and beetle bristles,we first demonstrated that the stiffness along the hair is 1000 to 30000 times that perpendicular to the hair.This stiffness difference is the key factor leading to the two hairy systems' functional differences.Slope of gecko setae reduces contact stiffness,increases contact points and real contact area that results in amazing adhesive abilities.On the other hand,stiff bristles in a beetle have higher contact stiffness,which reduces the real contact area and decreases the adhesion between two contact surfaces.Deformation of gecko setae destroys the hierarchical structure,increases the contact stiffness and results in a decrease of adhesion forces.Similarly,deformation of beetle bristles destroys the erect structure of the hair,interconnects the separated bristles and thus decreases the anti-adhesive functions.These observations inspire us in designing anti-adhesive and adhesive biomimetic systems     

表面活性剂对Al2O3基泡沫陶瓷性能的影响

采用三维网状的聚氨酯有机泡沫体作为载体制备Al₂O₃基泡沫陶瓷。选用了不同质量分数的木质素磺酸钙溶液作为表面活性剂对泡沫进行了表面活化,研究表面活性剂加入量对氧化铝基小孔泡沫陶瓷过滤器性能的影响。研究表明:随着活化剂质量分数的增大,试样的抗压强度和热震稳定性先升后降,当活化剂木质素质量分数为1.0%时,泡沫陶瓷性能最好,此时强度达到1.147 MPa,热震循环次数达到11次。     

PDMS microchannel fabrication technique based on microwire-molding

Micro-flow channel is basic functional component of microfluidic chip, and every step-forward of its construction technique has been receiving concern all over the world. This article presents a notcomplicated but flexible method for fabrication of micro-flow channels. This method mainly utilizes the conventional molding capability of polydimethylsiloxane （PDMS） and widespread commercial microwires as templates. We have fabricated out some conventional types of microchannels with different topological shapes, as examples for the demonstration of this flexible fabrication route which was not dependent on the stringent demands of photolithographical or microelectromechanical system （MEMS） techniques. The smooth surface, high-intensity, and high flexibility of the wires made it possible to create many types of topological structures of the two-dimensional or three-dimensional microchannel or channel array. The geometric shape of the cross-section of thus forming microchannel in PDMS was the negative of that of embedded-in microwire, in high-fidelity if suitable measures were taken. Moreover, such a microchannel fabrication process can easily integrate the conductivity and low resistivity of the metal wire to create micro-flow devices that are suitable for the electromagnetic control of liquid or the temperature regulation in the microchanneh Furthermore some preliminary optical analysis was provided for the observation of thus forming rounded microchannei. Based on this molding strategy, we even made some prototypes for functional microflow application, such as microsolenoids chip and temperature control gadgets. And an experiment of forming a droplet in the cross channel further confirmed the feasibility and applicability of this flexible microchannel forming technique.     

应用于成像系统的高矢高透镜阵列制备

在移动掩模光刻技术的基础上,本文提出一种可用于成像系统的高矢高透镜阵列制备的二次光刻方法。二次光刻分别用于减小抗蚀剂表面粗糙度和借助移动掩模光刻制备高矢高透镜阵列。通过这种方法,我们成功制备了矢高254 mm的透镜阵列。透镜矢高约为传统移动掩模光刻技术制备透镜阵列矢高的二倍。进而,制备的透镜阵列被用于集成成像系统,获得了高质量的三维图像。这一结果很好的证明了该种二次光刻方法可用于成像系统高矢高透镜阵列的制备,具有较好的应用前景。     

TiO_2光阳极有序微结构的纳米压印工艺

提出一种以常温紫外固化纳米压印技术实现定制化微结构TiO_2纳米晶岛薄膜制备的工艺,用于制备垂直于透明导电基底的TiO_2薄膜光阳极.混合TiO_2粉体、分散剂、乳化剂、酒精和光固化树脂等,制备可紫外光固化的TiO_2溶胶,并经步进压印形成宽度为3μm的具有离散纳米晶岛微结构的薄膜,经保压复型优化压印工艺后处理,保证了离散纳米晶岛微结构的高保真度.经600℃烧结去除薄膜中的掺杂物,退火至450℃后获得了定制化微特征的锐钛矿型TiO_2半导体薄膜.在N719染料敏化条件下,制备出了定制化微结构光阳极的染料敏化太阳能电池.AM1.5(0.1w/cm~2)光照条件下的测试实验结果表明,该电池的光电转化效率可达2.7%.此工艺有望应用于制备高稳定性固态或准固态电解质染料敏化太阳能电池.