Despite theoretical predictions that graphene should be impermeable to all gases, practical experiments on sealed nanodrums show small leak rates. Thus far, the exact mechanism for this permeation has remained unclear, because different potential leakage pathways have not been studied separately. Here, we demonstrate a sealing method consists of depositing SiO2 across edge suspended multilayer flakes using electron beam-induced deposition. By sealing, along graphene-SiO2 interface is...

The bending rigidity of two-dimensional (2D) materials is a key parameter for understanding the mechanics 2D NEMS devices. apparent graphene membranes at macroscopic scale differs from theoretical predictions micro-scale. This difference believed to originate thermally induced dynamic ripples in these atomically thin membranes. In this paper, we perform modal analysis estimate effective frequency spectrum their Brownian motion. Our method based on fitting resonance frequencies obtained...

In the last decade, graphene membranes have drawn tremendous attention due to their potential application in Nano-Electro-Mechanical Systems. this paper, we show that frequency response curves of resonators are powerful tools for dynamic characterization and extracting equivalent Young's modulus. For purpose, vibrations an electrostatically actuated circular membrane studied both experimentally numerically. The experiments reveal dependency linear nonlinear resonance nano-resonator on...

Characterization of nonlinear behavior micro-mechanical components in MEMS applications plays an important role their design process. In this paper, dynamics, stability and pull-in mechanisms electrically actuated circular micro-plate subjected to a differential pressure are studied. For purpose, reduced-order model based on energy approach is formulated. It has been shown that dynamics micro-plate, the presence pressure, significantly differs from those under purely electrostatic loads. The...

Electrostatic instability is one of the main features many electrostatic MEMS and NEMS devices. In this paper, we investigate how a plate-like electrode can be affected by differential pressure. The results study indicate that presence pressure have significant influence on equilibrium path, number location unstable points, post-instability behavior. As result, while system loaded unloaded electrically, might lead to snapping noticed behavior flat plate makes it very appealing for sensing...

Abstract This study aimed to investigate the biocompatibility and osseointegration of novel titanium (Ti) implants with a perforated part high surface roughness (Ra >4 μm) smooth solid (test group), as compared Ti (control group; Ra < 0.8 μm). Test control were implanted in rabbit femurs. After 4 15 weeks, host tissue reaction quality formed evaluated histopathology, while micro‐CT scans used quantitatively assess bone–implant contact (BIC), surrounding bone formation, ingrowth....

The electrostatic instability (pull-in) of a flat electrode in parallel plate capacitor has been shown to be highly sensitive external mechanical loads such as pressure. In this paper, we substantiate the possibility prompting additional unstable configurations system, with remarkable sensitivity applied This significant advantageous properties for sensing purposes. addition high and robustness pull-in voltage measurements, it can adjusted so that after configuration is met, snap-through new...

Micro-Electro-Mechanical devices have shown enormous popularity in engineering as sensors and actuators. In this paper, the instability, i.e. dynamic pull-in behavior, of an electrically actuated circular micro-membrane is studied. order to investigate periodic solutions, detect bifurcations follow branches solution, non-linear equation motion derived using energy approach, and, solved by a pseudo arc-length continuation collocation technique. It has been that, both hardening and/or...

Owing to their atomic thickness and low bending rigidity, suspended two-dimensional (2D) materials are prone wrinkle formation. Here, we use molecular dynamics (MD) simulations probe the effect of these wrinkles on nonlinear elasticity atomically thin graphene membranes. We observe a stress–strain response that consists two linear regions separated by transition. It is found this transition sharp in membranes where formed uneven stresses at boundaries. However, when crystal defects, seen be...

This paper studies the effective parameters of a skilled service in playing tennis and determines their relationship with skill deals. Effective plays an important role gaining more desirable result most factor success getting scores depends on player’s skills serving service. The characteristics good are high speed ball precision landing ball. several affecting these two characteristic service, studied this paper. Therefore, Kinematic 8 Iranian professional athletes first division league...

Surface stress-based measurement is a relatively new mechanism in biological and chemical sensing. The viability of this depends on the maximum sensitivity, accuracy, precision that can be achieved with these sensors. In paper, an analytical approximate solution finite-element model are employed to describe electromechanical behavior surface sensor capacitive measurements. proposed model, circular membrane assumed as sensing component, while only smaller concentric area its subjected change...

In the last decades, Micro-Electro-Mechanical Systems (MEMS) have drawn immense attention due to their potential use in a wide variety of modern applications, including micro-mechanical sensors and actuators. MEMS are devices combining mechanical electrical components between 1 100 micrometers, all integrated into single chip. The performance these hinges on deflection movement clearly, improvement innovation require comprehensive knowledge in-depth understanding nonlinear mechanics...

The bending rigidity of two-dimensional (2D) materials is a key parameter for understanding the mechanics 2D NEMS devices. apparent graphene membranes at macroscopic scale differs from theoretical predictions micro-scale. This difference believed to originate thermally induced dynamic ripples in atomically thin membrane. In this paper, we perform modal analysis estimate effective frequency spectrum their Brownian motion. Our method based on fitting resonance frequencies obtained motion...

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