scholarly journals The Effect of Edge Mode on Mass Sensing for Strained Graphene Resonators

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 189
Author(s):  
Xing Xiao ◽  
Shang-Chun Fan ◽  
Cheng Li
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Fundamental Mode ◽  
Mass Measurement ◽  
Mass Detection ◽  
Edge Mode ◽  
Mass Sensing ◽  
Constant Frequency ◽  
Strained Graphene ◽  
Dynamics Simulations

Edge mode could disturb the ultra-subtle mass detection for graphene resonators. Herein, classical molecular dynamics simulations are performed to investigate the effect of edge mode on mass sensing for a doubly clamped strained graphene resonator. Compared with the fundamental mode, the localized vibration of edge mode shows a lower frequency with a constant frequency gap of 32.6 GHz, despite the mutable inner stress ranging from 10 to 50 GPa. Furthermore, the resonant frequency of edge mode is found to be insensitive to centrally located adsorbed mass, while the frequency of the fundamental mode decreases linearly with increasing adsorbates. Thus, a mass determination method using the difference of these two modes is proposed to reduce interferences for robust mass measurement. Moreover, molecular dynamics simulations demonstrate that a stronger prestress or a higher width–length ratio of about 0.8 could increase the low-quality factor induced by edge mode, thus improving the performance in mass sensing for graphene resonators.

scholarly journals Fast leaps between millisecond confinements govern Ase1 diffusion along microtubules

2021 ◽  
Author(s):  
Łukasz Bujak ◽  
Kristýna Holanová ◽  
Antonio García Marín ◽  
Verena Henrichs ◽  
Ivan Barvík ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Cell Division ◽  
Molecular Dynamics Simulations ◽  
Interaction Potential ◽  
Electrostatic Potential ◽  
Fundamental Mode ◽  
Protein Translocation ◽  
Periodic Surface ◽  
Tubulin Dimer ◽  
Dynamics Simulations

AbstractDiffusion is the most fundamental mode of protein translocation within cells. Confined diffusion of proteins along the electrostatic potential constituted by the surface of microtubules, although modeled meticulously in molecular dynamics simulations, has not been experimentally observed in real-time. Here, we used interferometric scattering microscopy to directly visualize the movement of the microtubule-associated protein Ase1 along the microtubule surface at nanometer and microsecond resolution. We resolved millisecond confinements of Ase1 and fast leaps between these positions of dwelling preferentially occurring along the microtubule protofilaments, revealing Ase1’s mode of diffusive translocation along the microtubule’s periodic surface. The derived interaction potential closely matches the tubulin-dimer periodicity and the distribution of the electrostatic potential on the microtubule lattice. We anticipate that mapping the interaction landscapes for different proteins on microtubules, finding plausible energetic barriers of different positioning and heights, will provide valuable insights into regulating the dynamics of essential cytoskeletal processes, such as intracellular cargo trafficking, cell division, and morphogenesis, all of which rely on diffusive translocation of proteins along microtubules.

SPIN IN CARBON NANOTUBE-BASED OSCILLATORS

2006 ◽  
Vol 05 (01) ◽  
pp. 47-55 ◽  
Author(s):  
SHAOPING XIAO ◽  
RAY HAN ◽  
WENYI HOU
Keyword(s):  
Molecular Dynamics ◽  
Carbon Nanotube ◽  
Energy Dissipation ◽  
Angular Velocity ◽  
Molecular Dynamics Simulations ◽  
Room Temperature ◽  
Constant Frequency ◽  
Oscillator System ◽  
Rocking Motion ◽  
Dynamics Simulations

In this paper, molecular dynamics simulations are performed on a [10, 10]/[5, 5] carbon nanotube-based oscillator. In our work, we observed a spin phenomenon of the inner tube when it oscillated in an isolated oscillator system. If there exist a rocking motion when the inner tube started to oscillate, an axial torque would be observed, and it would drive the inner tube to spin. When the oscillation became stable, the torque almost vanished, and the spin was stabilized with a constant frequency of 21.78 GHz. Such a spin phenomenon was also observed when the oscillator system was at a room temperature of 300 K. However, both magnitude and direction of the spin angular velocity varied from time to time, even after the oscillation of the inner tube stopped due to the energy dissipation.

Sign in / Sign up

Export Citation Format

Share Document