Biological surface science

Biological surface science (BioSS), as defined here is the broad interdisciplinary area where properties and processes at interfaces between synthetic materials and biological environments are investigated and biofunctional surfaces are fabricated. Six examples are used to introduce and discuss the subject: Medical implants in the human body, biosensors and biochips for diagnostics, tissue engineering, bioelectronics, artificial photosynthesis, and biomimetic materials. They are areas of varying maturity, together constituting a strong driving force for the current rapid development of BioSS. The second driving force is the purely scientific challenges and opportunities to explore the mutual interaction between biological components and surfaces.

Model systems range from the unique water structures at solid surfaces and water shells around proteins and biomembranes, via amino and nucleic acids, proteins, DNA, phospholipid membranes, to cells and living tissue at surfaces. At one end of the spectrum the scientific challenge is to map out the structures, bonding, dynamics and kinetics of biomolecules at surfaces in a similar way as has been done for simple molecules during the past three decades in surface science. At the other end of the complexity spectrum one addresses how biofunctional surfaces participate in and can be designed to constructively participate in the total communication system of cells and tissue.

Biofunctional surfaces call for advanced design and preparation in order to match the sophisticated (bio) recognition ability of biological systems. Specifically this requires combined topographic, chemical and visco-elastic patterns on surfaces to match proteins at the nm scale and cells at the micrometer scale. Essentially all methods of surface science are useful. High-resolution (e.g. scanning probe) microscopies, spatially resolved and high sensitivity, non-invasive optical spectroscopies, self-organizing monolayers, and nano- and microfabrication are important for BioSS. However, there is also a need to adopt or develop new methods for studies of biointerfaces in the native, liquid state.

For the future it is likely that BioSS will have an even broader definition than above and include native interfaces, and that combinations of molecular (cell) biology and BioSS will contribute to the understanding of the “living state”.  

8～14μm波长低红外发射率涂料的研究

研究了红外隐身涂料粘合剂的物理和化学性能,以及红外隐身涂料粘合剂、填料、颜料颗粒的红外发射率。通过研究发现,铝粉和氧化铅具有较低的发射率,并得到了以有机硅清漆和EPDM(三元乙丙橡胶)接枝聚合物为基体的低红外发射率涂料,它有助于对红外隐身涂料粘合剂、填料、颜料颗粒的选择。  

粘接质量超声检测研究

高波阻抗层下多层低波阻抗层间脱粘的超声检测问题是具有普遍意义又很难解决的检测问题，本文介绍了我们近年来在些方面的一些研究进展，首先从传播特性入手总结出几个有用的特征规律，并结合这些物理特征规律选取相应的信号处理手段，从方法上实现多层界面的脱粘检测，并作了多种技术集成，做出有实际应用价值的检测系统。  

W过渡层结合界面对金刚石薄膜在WC-6%Co上的附着力的影响

 在微波等离子体化学气相沉积装置中，采用负偏压形核等方法，研究两种不同的W过渡层/基体结合界面对金刚石薄膜与WC-6%Co附着力的影响。采用氢等离子体脱碳、磁控溅射镀W、高偏压碳化等方法，在YG6衬底表面形成化学反应型界面，W膜在碳化时和基体WC连为一体，极大地增加了W膜与基体的附着力，明显优于直接镀钨、碳化形成的物理吸附界面。在高负偏压下碳化，能提高表面粗糙度，增加膜与基体机械钳合，而负偏压形核增加核密度，从而增加膜与基体的接触面积，结果极大地提高了金刚石薄膜的附着力。  

激光驱动飞片超高速发射技术实验研究

 介绍了影响激光驱动超高速发射技术的各种因素。分析了激光能量、激光光束空间分布对飞片发射速度及完整性的影响和飞片靶镀膜工艺对飞片速度及完整性的影响。结果表明：空间分布为“平顶型”的激光束有利于发射出完整的飞片。在膜与基底之间增加过渡层Cr可以大大提高膜与基底之间的附着力，从而提高飞片的发射速度。实验上利用波长1 064 nm、脉宽10 ns、能量835 mJ的激光使厚度5 μm、直径1 mm的铝飞片的发射速度达到10.4 km/s。大大提升了对微米级空间碎片速度的发射能力。  

磁控溅射CNx薄膜的附着力、粗糙度与衬底偏压的关系

对磁控溅射生长在单晶Si(001)衬底上的CNx薄膜的附着力、粗糙度与衬底偏压的关系进行了研究。CNx薄膜沉积实验在纯N2的环境下进行．衬底温度(Ts)保持在350℃．衬底偏压(Vb)在0～-150V之间变化。利用原子力显微镜(AFM)和划痕试验机来测量CNx薄膜的表面粗糙度及对衬底的附着力。AFM和划痕实验的结果显示衬底偏压Vb对CNx薄膜的附着力和表面粗糙程度的影响很大，在-100V偏压下生长的CNx薄膜表面最光滑(粗糙度最小)，同时对Si(001)衬底的附着力最好。最后根据实验结果确定了在单晶Si(001)衬底上生长光滑而且附着力好的CNx薄膜的最佳实验条件。  

Studies on influence of zinc immersion and fluoride on nickel electroplating on magnesium alloy AZ91D

The effect of zinc immersion and the role of fluoride in nickel plating bath were mainly investigated in nickel electroplating on magnesium alloy AZ91D. The state of zinc immersion, the composition of zinc film and the role of fluoride in nickel plating bath were explored from the curves of open circuit potential (OCP) and potentiodynamic polarization, the images of scanning electron microscopy (SEM) and the patterns of energy dispersive X-ray (EDX). Results show that the optimum zinc film mixing small amount of Mg(OH)₂ and MgF₂ is obtained by zinc immersion for 30-90 s. The corrosion potential of magnesium alloy substrate attached zinc film will be increased in nickel plating bath and the quantity of MgF₂ sandwiched between magnesium alloy substrate and nickel coating will be reduced, which contributed to produce nickel coating with good performance. Fluoride in nickel plating bath serves as an activator of nickel anodic dissolution and corrosion inhibitor of magnesium alloy substrate. 1.0-1.5 mol dm⁻³ of F⁻ is the optimum concentration range for dissolving nickel anode and protecting magnesium alloy substrate from over-corrosion in nickel plating bath. The nickel coating with good adhesion and high corrosion resistance on magnesium alloy AZ91D is obtained by the developed process of nickel electroplating. This nickel layer can be used as the rendering coating for further plating on magnesium alloys.  

金刚石薄膜的结构特征对薄膜附着性能的影响

在不同实验条件下，用微波等离子体化学气相沉积设备在硬质合金(WC+6%Co)衬底上沉积了 具有不同结构特征的金刚石薄膜.用Raman谱表征薄膜的品质和应力，用压痕实验表征薄膜的 附着性能，考察了薄膜中sp²杂化碳含量、形核密度、薄膜厚度对薄膜附着性能 的影响.结 果表明：sp²杂化碳的缓冲作用使薄膜中sp²杂化碳的含量对薄膜中 残余应力有较大的影 响，从而使薄膜压痕开裂直径统计性地随sp²杂化碳含量的增加而减小；仅仅依 靠超声遗 留的金刚石晶籽提高形核密度并不能有效改变薄膜与硬质合金基体之间的化学结合状况，从 而不能有效提高薄膜在衬底上的附着性能；在薄膜较薄时，晶粒之间没有压应力的存在，开 裂直径并不明显随厚度增加而增加，只有当薄膜厚度增加到一定值，晶粒之间才有较强压应 力存在，开裂直径随厚度的增加而较为迅速地增加.  

杂化溶胶改性紫外光固化胶粘剂的研究

 以自制的杂化溶胶对紫外光固化丙烯酸酯胶粘剂进行改性，得到了具有高粘接强度，对丙酮、乙醇、氯仿等具有明显的耐溶剂性的紫外光固化胶粘剂。实验发现：活性稀释剂中含有较多的羟基、羧基时，此胶粘剂对玻璃的粘接强度较高；胶层粘接力随杂化溶胶用量的增加先增大，后减小，当杂化溶胶中的固体质量为光敏树脂的60％时，胶粘剂的剪切强度达到最大（12MPa）。  

Mo离子注入对金刚石涂层附着性能的影响

采用Mo离子注入工艺对YG6硬质合金基体表面进行处理,用微波等离子体CVD(MPCVD)法沉积金刚石涂层,研究了Mo离子注入工艺对金刚石涂层附着性能的影响.结果表明,Mo离子注入后,硬质合金基体表面的化学成分发生了明显变化;采用适当剂量的Mo离子注入基体,可使CVD金刚石涂层的附着性能显著提高.