玫瑰花状氢氧化钴的结构和浸润性研究

在没有任何表面活性剂条件下,通过简单的方法首次合成了玫瑰花状β-Co(OH)₂微晶。玫瑰花状β-Co(OH)₂微晶宽3~5 μm,厚2~3 μm,是由平均厚度为15 nm的纳米片所组成。玫瑰花状β-Co(OH)₂组成的薄膜的接触角为158.5°±1.2°,表面处于任意的角度,水滴都不会滴落。     

自卸汽车装卸粘性土时粘附规律的统计分析

本文通过对自卸汽车的现场施工进行抽样调查，采用数理统计、灰色关联分析和模糊分析等方法，分析了自卸汽车粘土部位的变化规律和自卸汽车粘附积土的影响因素对粘土量的影响，揭示了自卸汽车的粘土规律，为通过工程仿生途径解决自卸汽车粘附积土问题创造了条件。     

利用胶体探针技术研究多巴与纳米、微米及微纳复合结构表面之间的相互作用

通过在硅片表面有机蒸镀不同厚度的二十九烷制备了不同晶体密度的仿生旱金莲叶面蜡质纳米结构表面,采用端基修饰多巴的原子力显微镜胶体探针,对各纳米结构表面进行了粘附性能测试,发现蒸镀200 nm厚度二十九烷结晶的纳米结构表面具有较低粘附力。采用反应离子刻蚀方法制备了不同高度的硅材质仿生鲨鱼皮微米结构表面,并选择了200 nm厚度二十九烷在仿生鲨鱼皮表面进行有机蒸镀制备了微纳复合结构表面,通过胶体探针的研究发现多巴与高度为1、3、5μm微纳复合结构表面的粘附力均小于与200 nm厚度二十九烷结晶的纳米结构表面之间的粘附力,说明微纳复合结构表面具有很强的抗多巴粘附能力,并且这种复合结构表面相对于硅材质的仿生鲨鱼皮微米结构表面还兼有旱金莲叶面的强疏水性和极佳的抗水粘附能力。     

电磁处理对水溶液中碳酸钙微粒沉降及附着性能的影响

通过Zeta电位、表面自由能及其分量、粘附功等热力学参数的测定与分析, 研究了电磁处理对等物质的量Na₂CO₃与CaCl₂溶液混合生成的碳酸钙微粒的沉积特性及阻垢机理. 结果显示电磁处理可以使碳酸钙微粒的Zeta电位绝对值减小约5 mV, 同时加快碳酸钙微粒的沉降速度. 经电磁处理生成的碳酸钙微粒的表面自由能为31.59 mJ•m^－2, 比未经处理时减小30%, 同时表面自由能Lifshitz-van der Waals分量从处理前的43.53 mJ•m^－2下降到25.50 mJ•m^－2, 说明成垢溶液的电磁处理可以提高碳酸钙微粒的热力学稳定性. 水溶液中碳酸钙微粒与316L不锈钢表面之间的理论粘附功计算显示, 电磁处理降低了该理论粘附功, 使碳酸钙微粒在不锈钢表面的附着能力下降.     

复制模塑法制备超疏水表面及其应用

Two kinds of poly(dimethylsiloxane) (PDMS) rough surfaces with different geometries which were square pillars and parallel grating were designed and fabricated by replica molding (REM). Scanning electron microscope (SEM) images showed that the fabricated samples had high fidelity. The contact angles of water droplet on the PDMS square pillars surface and parallel grating surface were (154.6依0.7)° and (160.2依1.9)°, respectively, and the sliding angles were not larger than 6° and 3°, respectively, which attained to the standard of superhydrophobicity. The experimental result of blood platelets adhesion demonstrated that these two superhydrophobic PDMS rough surfaces had better blood compatibility than PDMS planar surface. The crazing and shedding of microstructures in the replica molding were also analyzed and discussed. All results showed that these superhydrophobic materials may be used in industrial and agricultural fields and bioengineering field.     

CONCAVE BIOLOGICAL SURFACES FOR STRONG WET ADHESION

Plant leaves, insects and geckos are masters of adhesion or anti-adhesion by smartly designed refined surface structures with micro- and nano- ＇technologies＇. Understanding the basic principles in the design of the unique surface structures is of great importance in the manufacture or synthesis of micro- and nano- devices in MEMS or NEMS. This study is right inspired by this effort, focusing on the mechanics of wet adhesion between fibers having concave tips and a flat substrate via capillary forces. We show that the concave surface can effectively enhance the wet adhesion by reducing the effective contact angle of the fiber, firmly pinning the liquid bridge at its circumferential edge. A critical contact angle is identified below which the adhesion strength can achieve its maximum, being insensitive to the contact angle between the fiber and liquid. The analytical expression for the critical angle is derived. Then a tentative design for the profile of concave surfaces is proposed, considering the effects of chamfering size, deformation and buckling, etc. The effect of liquid volume on the wet adhesion of multiple-fiber system is also discussed.     

含悬挂羧基手臂聚乳酸材料的合成与血小板粘附性研究

制备了乳酸-β-苹果酸共聚物,并在此基础上进一步修饰合成了含悬挂羟基(PLMAHE)以及悬挂羧基(PCA-PLA)的聚乳酸共聚物,利用原子力显微镜及环境扫描电镜,观察了聚合物膜的表面形貌以及粘附在聚合物膜上的血小板数量与形态.结果表明含悬挂羟基材料表面粘附血小板时发生聚集并有伪足生成,含悬挂羧基材料表面血小板粘附数量较少且形态正常,有望成为优良的抗凝血材料.     

Evaluating of Adhesion Property of ULSI Interconnect Films by the Surface Acoustic Waves

The technique of surface acoustic waves （SAWs） is a very promising method for determining film properties such as Young＇s modulus, density and film thickness nondestructively and accurately. The dispersion property of SAWs is also affected largely from the adhesion property of films, which is revealed by the bonding spring assumption described. This SAW method could offer a quantitative evaluation of the film adhesion from the curvature of SAW dispersion lines affected by the normal and shear spring constants. The method is applied to numerically characterize the adhesion property of the typical ultra-large-scale integrated circuit interconnect layered structure of a thin Cu film deposited on the Si substrate as well as a SiO2 thin film on a Si
substrate.     

Measurement of interaction force between RGD-peptide and Hela cell surface by optical tweezers

Since RGD peptides (R: arginine; G: glycine; D: aspartic acid) are found to promote cell adhesion, they are modified at numerous materials surface for medical applications such as drug delivery and regenerative medicine. Peptide-cell surface interactions play a key role in the above applications. In this letter, we study the adhesion force between the RGD-coated bead and Hela cell surface by optical tweezes. The adhesion is dominated by the binding of α5β1 and RGD-peptide with higher adhesion probability and stronger adhesion strength compared with the adhesion of bare bead and cell surface. The binding force for a single α5β1 -GRGDSP pair is determined to be 16.8 pN at a loading rate of 1.5 nN/s. The unstressed off-rate is 1.65 × 10-2s-1 and the distance of transition state for the rigid binding model is 3.0 nm.