Vascular journey and adhesion mechanics of micro-sized carriers in narrow capillaries

The adhesion feature of graphene on metal substrates is important in graphene synthesis, transfer and applications, as well as for graphene-reinforced metal matrix composites. We investigate the adhesion energy of graphene nanosheets (GNs) on iron substrate using molecular dynamic (MD) simulations. Two Fe–C potentials are examined as Lennard–Jones (LJ) pair potential and embedded-atom method (EAM) potential. For LJ potential, the adhesion energies of monolayer GN are 0.47, 0.62, 0.70 and 0.74 J/m2 on the iron {110}, {111}, {112} and {100} surfaces, respectively, compared to the values of 26.83, 24.87, 25.13 and 25.01 J/m2 from EAM potential. When the number of GN layers increases from one to three, the adhesion energy from EAM potential increases. Such a trend is not captured by LJ potential. The iron {110} surface is the most adhesive surface for monolayer, bilayer and trilayer GNs from EAM potential. The results suggest that the LJ potential describes a weak bond of Fe–C, opposed to a hybrid chemical and strong bond from EAM potential. The average vertical distances between monolayer GN and four iron surfaces are 2.0–2.2 Å from LJ potential and 1.3–1.4 Å from EAM potential. These separations are nearly unchanged with an increasing number of layers. The ABA-stacked GN is likely to form on lower-index {110} and {100} surfaces, while the ABC-stacked GN is preferred on higher-index {111} surface. Our insights of the graphene adhesion mechanics might be beneficial in graphene growing, surface engineering and enhancement of iron using graphene sheets.

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Adhesion mechanics of graphene membranes

Solid State Communications ◽

10.1016/j.ssc.2012.04.029 ◽

2012 ◽

Vol 152 (15) ◽

pp. 1359-1364 ◽

Cited By ~ 94

Author(s):

J.S. Bunch ◽

M.L. Dunn

Keyword(s):

Adhesion Mechanics ◽

Graphene Membranes

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Attachment of zebra and quagga mussel adhesive plaques to diverse substrates

Scientific Reports ◽

10.1038/s41598-021-03227-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bryan D. James ◽

Kenneth M. Kimmins ◽

Minh-Tam Nguyen ◽

Alexander J. Lausch ◽

Eli D. Sone

Keyword(s):

Failure Mode ◽

Protein Composition ◽

Freshwater Mussel ◽

Marine Mussel ◽

Quagga Mussels ◽

Spreading Dynamics ◽

Marine Mussels ◽

Adhesion Mechanics ◽

Mussel Adhesive ◽

The Individual

AbstractLike marine mussels, freshwater zebra and quagga mussels adhere via the byssus, a proteinaceous attachment apparatus. Attachment to various surfaces allows these invasive mussels to rapidly spread, however the adhesion mechanism is not fully understood. While marine mussel adhesion mechanics has been studied at the individual byssal-strand level, freshwater mussel adhesion has only been characterized through whole-mussel detachment, without direct interspecies comparisons on different substrates. Here, adhesive strength of individual quagga and zebra mussel byssal plaques were measured on smooth substrates with varying hydrophobicity—glass, PVC, and PDMS. With increased hydrophobicity of substrates, adhesive failures occurred more frequently, and mussel adhesion strength decreased. A new failure mode termed 'footprint failure' was identified, where failure appeared to be adhesive macroscopically, but a microscopic residue remained on the surface. Zebra mussels adhered stronger and more frequently on PDMS than quagga mussels. While their adhesion strengths were similar on PVC, there were differences in the failure mode and the plaque-substrate interface ultrastructure. Comparisons with previous marine mussel studies demonstrated that freshwater mussels adhere with comparable strength despite known differences in protein composition. An improved understanding of freshwater mussel adhesion mechanics may help explain spreading dynamics and will be important in developing effective antifouling surfaces.

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Adhesion Interaction and Adhesion Mechanics. Theory and Its Application

Polymer Science Series D ◽

10.1134/s1995421221040250 ◽

2021 ◽

Vol 14 (4) ◽

pp. 522-531

Author(s):

R. A. Turusov

Keyword(s):

Adhesion Interaction ◽

Adhesion Mechanics

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Macroscale adhesion of gecko setae reflects nanoscale differences in subsurface composition

Journal of The Royal Society Interface ◽

10.1098/rsif.2012.0587 ◽

2013 ◽

Vol 10 (78) ◽

pp. 20120587 ◽

Cited By ~ 35

Author(s):

Peter Loskill ◽

Jonathan Puthoff ◽

Matt Wilkinson ◽

Klaus Mecke ◽

Karin Jacobs ◽

...

Keyword(s):

Layer Thickness ◽

Interfacial Adhesion ◽

Theoretical Calculations ◽

Van Der Waals ◽

Adhesion Forces ◽

Inhomogeneous Materials ◽

Subsurface Layers ◽

Adhesion Mechanics ◽

Van Der Waals Energies ◽

Theoretical Results

Surface energies are commonly used to determine the adhesion forces between materials. However, the component of surface energy derived from long-range forces, such as van der Waals forces, depends on the material's structure below the outermost atomic layers. Previous theoretical results and indirect experimental evidence suggest that the van der Waals energies of subsurface layers will influence interfacial adhesion forces. We discovered that nanometre-scale differences in the oxide layer thickness of silicon wafers result in significant macroscale differences in the adhesion of isolated gecko setal arrays. Si/SiO 2 bilayer materials exhibited stronger adhesion when the SiO 2 layer is thin (approx. 2 nm). To further explore how layered materials influence adhesion, we functionalized similar substrates with an octadecyltrichlorosilane monolayer and again identified a significant influence of the SiO 2 layer thickness on adhesion. Our theoretical calculations describe how variation in the SiO 2 layer thickness produces differences in the van der Waals interaction potential, and these differences are reflected in the adhesion mechanics. Setal arrays used as tribological probes provide the first empirical evidence that the ‘subsurface energy’ of inhomogeneous materials influences the macroscopic surface forces.

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