High flexibility of DNA on short length scales probed by atomic force microscopy

2006 ◽  
Vol 1 (2) ◽  
pp. 137-141 ◽  
Author(s):  
Paul A. Wiggins ◽  
Thijn van der Heijden ◽  
Fernando Moreno-Herrero ◽  
Andrew Spakowitz ◽  
Rob Phillips ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Short Length ◽  
Length Scales ◽  
Force Microscopy ◽  
Atomic Force ◽  
High Flexibility

Multiscale Roughness of MEMS Surfaces

2004 ◽  
Author(s):  
Can K. Bora ◽  
Michael E. Plesha ◽  
Erin E. Flater ◽  
Mark D. Street ◽  
Robert W. Carpick ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Power Law ◽  
Multiscale Model ◽  
Length Scales ◽  
Microelectromechanical System ◽  
Force Microscopy ◽  
Atomic Force ◽  
Multiple Length Scales ◽  
Function Approximations

Investigation of contact and friction at multiple length scales is necessary for the design of surfaces in sliding microelectromechanical system (MEMS). A method is developed to investigate the geometry of asperities at different length scales. Analysis of density, height, and curvature of asperities on atomic force microscopy (AFM) images of actual silicon MEMS surfaces show these properties have a power law relationship with the sampling size used to define an asperity. This behavior and its similarity to results for fractal Weierstrass-Mandelbrot (W-M) function approximations indicate that a multiscale model is required to properly describe the surfaces.

Characterization and molecular engineering of surface-grafted polymer brushes across the length scales by atomic force microscopy

2010 ◽  
Vol 20 (24) ◽  
pp. 4981 ◽  
Author(s):  
Xiaofeng Sui ◽  
Szczepan Zapotoczny ◽  
Edmondo M. Benetti ◽  
Peter Schön ◽  
G. Julius Vancso
Keyword(s):  
Atomic Force Microscopy ◽  
Polymer Brushes ◽  
Molecular Engineering ◽  
Length Scales ◽  
Grafted Polymer ◽  
Force Microscopy ◽  
Atomic Force

Hierarchical, self-similar structure in native squid pen

Soft Matter ◽  
2014 ◽  
Vol 10 (30) ◽  
pp. 5541-5549 ◽  
Author(s):  
Fei-Chi Yang ◽  
Robert D. Peters ◽  
Hannah Dies ◽  
Maikel C. Rheinstädter
Keyword(s):  
Atomic Force Microscopy ◽  
Strong Correlation ◽  
Molecular Orientation ◽  
X Ray Diffraction ◽  
Length Scales ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Self Similar

The structure of native squid pen was investigated combining microscopy, atomic force microscopy, and X-ray diffraction. The experiments probed length scales from millimetres down to nanometres and indicate a strong correlation between macroscale structure and molecular orientation.

Atomic force microscopy based quantitative mapping of elastic moduli in phase separated polyurethanes and silica reinforced rubbers across the length scales

2011 ◽  
Vol 1318 ◽  
Author(s):  
Peter Schön ◽  
Kristóf Bagdi ◽  
Kinga Molnár ◽  
Patrick Markus ◽  
Saurabh Dutta ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Tensile Testing ◽  
Elastic Moduli ◽  
Hydroxyl Groups ◽  
Stoichiometric Ratio ◽  
Length Scales ◽  
Rubber Blends ◽  
Force Microscopy ◽  
Rubber Blend ◽  
Atomic Force

ABSTRACTIn the work presented here atomic force microscopy (AFM) based mechanical mapping techniques - HarmoniX imaging and Peak Force Tapping - were applied to determine the surface elastic modulus of phase separated polyurethanes and silica reinforced rubbers across the length scales. Segmented polyether polyurethanes (PUs) were prepared with varying stoichiometric ratio of the isocyanate and hydroxyl groups. The effect of molar mass, as well as the type and number of end-groups on their morphology was investigated. Smooth PU samples for AFM imaging were prepared by ultramicrotonomy. The micro phase separated morphology of the phase separated PUs showed characteristic “fingerprint” AFM phase images. Surface modulus values obtained by AFM were compared to bulk modulus values obtained by tensile testing. The moduli were mapped quantitatively with nanoscale resolution and were in excellent agreement for both AFM modes. Surface mean moduli values do not coincide with bulk values obtained via tensile testing which is attributed to fundamentally different averaging procedures and effects that lead to the respective modulus values obtained via surface and volume averaging. EPDM and SBR rubbers and rubber blends thereof were prepared with varying concentrations of silica nanoparticles and studied in order to investigate the effect of different composition on the resulting morphology (filler distribution) and elastic moduli on a specific rubber or rubber blend sample. Elastic moduli of the rubber and rubber blend samples were first measured by bulk tensile testing. The morphology of the rubber samples was visualized by height and phase imaging. Surface elastic moduli of silica reinforced rubbers and rubber blends were mapped quantitatively and compared with bulk tensile test results. AFM allowed the determination of modulus distributions at the sections imaged. As potential reasons for the observed differences between bulk and surface modulus different averaging procedures like surface and bulk averaging of AFM vs. tensile testing, different filler distributions in SBR and EPDM and the AFM modulus calibration procedures can be named.

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