Silicon Straight Tube Fluid Density Sensor

Abstract

In this paper, a new and simple silicon straight tube is tested as a fluid density sensor. The tube structure has a hexagonal cross section. The fabrication process consists of anisotropic silicon etching and silicon fusion bonding. A tube structure with a length of 2.65 cm was tested. The sample volume is 9.3 µL. The first three modes of vibrations were investigated with a laser Doppler vibrometer for air and five liquid mixtures. The fluid density sensitivity of each mode was measured and the average was −256 ± 6 ppm (kg m −3 ) −1 around the density of water. The density of an unknown fluid can be continuously monitored using this sensor by measuring the resonance frequency of one of the vibration modes and extracting the density from the calibration curves.

2D MOSFET operation of a fully-depleted bulk MoS<inf>2</inf> at quasi-flatband back-gate

“…Note that this method can be applied to the devices with a flake thickness higher than the Debye length (~7.2 nm at this carrier concentration or doping regime). Series resistance: The series resistance, similar to an inversion-mode MOSFET in [4], can be extracted from the yintercept of R tot =V ds /I d vs. 1/(V gs -V fb ) in linear accumulation regime (V ds <V gs -V fb ), see Fig. 4, assuming accumulation as the dominant conduction mechanism in comparison to bulk conduction.…”

Prediction of Vibration Behavior of Micro-Circular Disks at Low Reynolds Number Regime

“…The two subproblems consist of determining the scalar potentials ðiÞ ðr; ; tÞ and ðiÞ ðr; ; tÞ satisfying the Helmholtz Eqs. (6) and (7). Introducing a new auxiliary variable ¼ j ffiffiffiffiffi j!…”

“…3 Like any other technology, to be able to implement microstructures and micro°uidic, 4,5 suitable production techniques have to be discovered. Microstructures and micro°uidics systems can have various applications in microresonators 6 and in targeted drug delivery devices and, in view of their excellent mechanical properties and hollow geometry. Bhirde 7 showed that the hollow geometry, for example, can be considered as drug delivery system in targeted therapy which results in a signi¯cant decrease in tumor size.…”

A Novel Slope Method for Measurement of Fluid Density with a Micro-cantilever under Flexural and Torsional Vibrations

“…For instance, Corman [ 7 ] presented a fully low-pressure encapsulated and closed-loop operated resonant fluid density sensor, where the required sample volume was only 35 µL. A new simple silicon straight tube was tested as a fluid density sensor in the study of Najmzadeh [ 8 ]; the length of the proposed tube was 2.65 cm, and the volume of the fluid sample was only 9.3 µL. The micro-cantilever is one of most common structures used for MEMS vibration devices, as it is simple and reliable [ 9 ].…”