共查询到19条相似文献,搜索用时 93 毫秒
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提出了一种测量物体微位移的新方法。原子力显微镜作为测量工具,样品和扫描器置于待测物体上,物体每移动一定距离就由AFM扫描获得一幅样品图像,由此获得一系列连续的序列图像。采用模板匹配方法检测相邻序列图像的偏移,从而可计算出物体的微位移。实验结果表明,用该方法还可实现物体二维方向的微位移测量,且精度达到纳米量级。 相似文献
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基于弯曲法的AFM微悬臂梁弹性常数标定技术 总被引:1,自引:0,他引:1
原子力显微镜(atomic force microscopy,AFM)在微纳米尺度力学测量领域有着广泛应用,其微悬臂梁探针的弹性常数是直接影响测量结果准确性的关键因素之一.弯曲法是标定微悬臂梁弹性常数的一类重要方法,基于弯曲标定原理提出了一种新的技术实现方案,并研制了相应的标定系统.借助精密运动定位台使微悬臂梁接触超精密天平并产生弯曲,分别以天平和光杠杆机构同步测得接触力和梁的弯曲量,再根据胡克定律直接算得弹性常数.利用所研制的系统对多种型号的微悬臂梁进行了标定,实验结果表明该系统具有良好的准确性和重复性,测量相对标准差小于5%. 相似文献
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以原子力显微镜单自由度模型为研究对象,在考虑激励和摩擦的情况下,应用相轨迹、Poincare图、分叉图等对Lennard-Jones potential力场模型系统进行分析计算,说明在其他参数不变激励频率为基频率时激励振幅对杆的影响,显示随着激励振幅的增大系统将发生分叉,在经过倍周期分叉后系统产生混沌. 相似文献
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分析了影响构件弯曲变形的主要因素及弯曲刚度与弯曲变形的联系和区别。对其在概念上的不同进行论述,并分析影响机械构件弯曲的主要因素,找出提高构件刚度的有效措施是零件结构设计的主要内容。 相似文献
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硅基微机械表面粘附及摩擦性能的AFM试验研究 总被引:1,自引:0,他引:1
在Si(100)基片上制备了十八烷基三氯硅烷(OTS)分子润滑膜,并用原子力显微镜(AFM)对比研究了施加OTS膜前后的硅表面的粘附、摩擦磨损性能。试验考虑了相对湿度和扫描速度对粘附、摩擦性能的影响。结果表明,相对于硅构件来讲,OTS膜表面粘附力较小,具有较小的摩擦因数,呈现较好的润滑性能;硅构件受湿度变化的影响比OTS膜明显。微构件的摩擦性能由于水合化学作用生成Si(OH)。润滑膜,使得其受相互间运动速度影响很大。OTS膜不仅是一种耐磨性较好的润滑膜,而且有良好的稳定性。 相似文献
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Atomic force microscope (AFM) is adapted to characterize an ultrasensitive piezoresistive pressure sensor based on microelectromechanical system (MEMS) technology. AFM is utilized in contact mode to exert force on several different micromachined diaphragm structures using a modified silicon cantilever with a particle attached to its end. The applied force is adjusted by changing the trigger voltage during each engage step of the probe-tip on the diaphragm surface. The contact force is determined from the force plots obtained for each trigger voltage in advanced force mode. Low force values in the range of 0.3–5 μN have been obtained with this method. This force induces strain on the bridge-arm of the diaphragm where the polysilicon resistor is located. The resultant change in the resistance produced due to varying force/pressure is measured using a delta mode current–voltage (I–V) measurement set-up. The contact mode AFM in conjunction with a nanovoltmeter enables the calibration of very sensitive force sensors down to 0.3 μN. 相似文献
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本文首次利用原子力显微镜(atomic force microscope,AFM)的超高分辨率功能研究H_2O_2处理引起的红细胞膜超微结构的变化,及低强度He-Ne激光照射H_2O_2处理过的红细胞使膜结构恢复的情况。实验结果表明,无论是H_2O_2作用还是激光照射红细胞整体都能维持双凹圆盘状结构;但用AFM得到的超微结构图显示H_2O_2作用的红细胞膜表面高低起伏明显,面上平均粗糙度增加,出现较宽、较深的孔洞。随着激光照射剂量的增加,红细胞膜表面的高低起伏减弱,面上平均粗糙度下降,孔洞变浅、变窄,细胞表面趋于平滑。分析表明,H_2O_2与红细胞内游离铁离子发生类Fenton反应产生的羟自由基(·OH)损伤红细胞膜的结构,细胞的超微结构发生较明显的变化,细胞膜表面的平均粗糙度明显增大,出现较深、较宽的孔洞;激光照射消除部分自由基的作用,较小剂量的激光照射能使损伤部分减弱,膜表面的平均粗糙度降低,孔洞变浅、变窄;较大剂量的激光照射使膜表面平均粗糙度进一步降低,孔洞进一步变浅、变窄,损伤进一步恢复。 相似文献
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基于AFM的机器人化纳米操作系统综述 总被引:1,自引:0,他引:1
对基于扫描隧道显微镜(Scanning tunnel microscope,STM)及原子力显微镜(Atomicforcemicroscope,AFM)的纳米操作技术发展进行阐述,针对其中存在的主要问题,引述出机器人化纳米操作的必要性。接着,对国内外机器人化纳米操作系统的研究进展、现状及存在的主要问题进行详细分析,提出基于AFM的机器人化纳米操作系统的结构原型,并指出实现机器人化纳米操作所需解决的关键技术问题及相应的解决方案之一,为进行深入的机器人化纳米操作研究提供了可以借鉴的研究方向。 相似文献
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This paper describes an interferometric platform for measuring the full-field deflection of atomic force microscope (AFM) probes and generic cantilevers during quasi-static loading. The platform consists of a scanning white light interferometer (SWLI), holders for the cantilevers, a translation stage, a rotation (tip-tilt) stage, and an adapter plate to connect these items to the SWLI table. Visualization of cantilever bending behavior is demonstrated for snap-in against a rigid surface, cantilever-on-cantilever tests, and a damaged AFM probe. A new approach to normal force calculation using a polynomial fit to the cantilever deflection profile is also presented and verified experimentally. The method requires only the coefficient for the third order (cubic) term from the fit to the deflection profile, the elastic modulus, and the area moment of inertia for the cantilever under test. 相似文献
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Yoomin Ahn Takahito Ono Masayoshi Esashi 《Journal of Mechanical Science and Technology》2008,22(2):308-311
Silicon cantilever arrays with a very small pitch for parallel AFM operations were studied. We fabricated 1x104 in eight groups
and 1x30 Si probe arrays and produced a smaller pitch (15 μm) between probe tips by using Si anisotropic etching with a vertical
wall shaped oxide mask. The vertical controls of Si probes were able to operate individually or in a group by integrating
electrostatic actuators into the cantilevers of the probes. The fabricated Si cantilever arrays showed reasonable dynamic
characteristics for the probe cantilever and reliable parallel operation of AFM. 相似文献
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To develop force measurements using an atomic force microscope (AFM) in a quantitative manner, it is necessary to estimate the number density of target molecules on a sample surface, and for this, the sensitivity of detection should be known. In this study, the AFM was used as a mechanical detector and an antigen and its antibody were used as a model to evaluate the sensitivity of detection. Antigens were immobilized on a glass surface and number density was estimated by monitoring optical absorbance due to product formation by the reaction of crosslinkers. The concentration of antigen was controlled by mixing control peptides. A microbead was used as a probe and antibodies were immobilized on the bead. AFM force measurements were then made for a range of number densities in the order of 10–106 antigen molecules per square micrometer of surface and were compared to evaluate the sensitivity of detection. Our result establishes the reliability of estimating a number of molecules like receptors on the cell surface, and indicates that the AFM is useful as a mechanical detector with high sensitivity. 相似文献
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We have developed a high-speed scanning near-field optical microscope (SNOM)/atomic force microscope (AFM) system including dual feedback controllers. The system includes an additional piezoelectric actuator with fast response in the z direction and a correction circuit to eliminate unnecessary components from the feedback signal. From the measurement of a patterned chromium layer of 2 × 2 μm2 checks on a quartz glass plate, we confirmed that our system had more effective feedback control and faster scanning than current SNOM/AFM systems that use only a piezo-tube. The scanning speed of the present system was estimated to be about five times faster than that of current SNOM/AFM systems. 相似文献