scholarly journals Coupled WGMs in a Dielectric Microsphere: Proof-of-Concept of Optical Pressure Microsensor

2021 ◽  
Author(s):  
Igor Minin ◽  
Oleg Minin ◽  
Yuri Geints
Keyword(s):  
Ambient Pressure ◽  
Resonant Mode ◽  
Proof Of Concept ◽  
Sensing Element ◽  
Particle Volume ◽  
Pressure Sensing ◽  
Whispering Gallery ◽  
Pressure Sensitive ◽  
Exact Position ◽  
Optical Pressure

We propose the physical proof-of-concept of a new simple miniature pressure sensor based on the whispering gallery modes (WGMs) optically excited in a dielectric microsphere placed near a flexible reflective membrane, which acts as an ambient pressure sensing element. WGMs excitation is carried out by free-space coupling of optical radiation to a microsphere. The distinctive feature of proposed sensor design is double excitation of optical eigenmodes by forward and backward propagating radiation reflected from a membrane that causes WGMs interference in particle volume. The optical intensity of resulting resonant field established in the microsphere carries information about the exact position of the pressure-loaded reflecting membrane. The sensitivity of the proposed sensor strongly depends on the quality factor of the excited resonant mode, as well as geometrical and mechanical parameters of the flexible membrane. We propose to register not the displacement of the position of the WGM resonance, but the change in its amplitude under the influence of the change in the distance between the sphere and the mirror under the influence of pressure. Important advantages of the proposed sensor are miniature design (linear sensor dimensions depends only on the membrane diameter) and the absence of a mechanical contact of pressure-sensitive element with WGM resonator.

scholarly journals Strategy for fast manufacturing of 3D hydrodynamic focusing multilayer microfluidic chips and its application for flow-based synthesis of gold nanoparticles

2021 ◽  
Vol 25 (8) ◽  
Author(s):  
Yanwei Wang ◽  
Michael Seidel
Keyword(s):  
Gold Nanoparticles ◽  
Microfluidic Devices ◽  
Microfluidic Chips ◽  
Proof Of Concept ◽  
Hydrodynamic Focusing ◽  
Pressure Sensitive Adhesive ◽  
Pmma Sheet ◽  
Pressure Sensitive ◽  
Working Device ◽  
Channel Structures

AbstractFabrication of 3D microfluidic devices is normally quite expensive and tedious. A strategy was established to rapidly and effectively produce multilayer 3D microfluidic chips which are made of two layers of poly(methyl methacrylate) (PMMA) sheets and three layers of double-sided pressure sensitive adhesive (PSA) tapes. The channel structures were cut in each layer by cutting plotter before assembly. The structured channels were covered by a PMMA sheet on top and a PMMA carrier which contained threads to connect with tubing. A large variety of PMMA slides and PSA tapes can easily be designed and cut with the help of a cutting plotter. The microfluidic chip was manually assembled by a simple lamination process.The complete fabrication process from device design concept to working device can be completed in minutes without the need of expensive equipment such as laser, thermal lamination, and cleanroom. This rapid frabrication method was applied for design of a 3D hydrodynamic focusing device for synthesis of gold nanoparticles (AuNPs) as proof-of-concept. The fouling of AuNPs was prevented by means of a sheath flow. Different parameters such as flow rate and concentration of reagents were controlled to achieve AuNPs of various sizes. The sheet-based fabrication method offers a possibility to create complex microfluidic devices in a rapid, cheap and easy way.

CMOS-MEMS Based Current Mirror MOSFET Embedded Pressure Sensor for Healthcare and Biomedical Applications

2013 ◽  
Vol 647 ◽  
pp. 315-320 ◽  
Author(s):  
Pradeep Kumar Rathore ◽  
Brishbhan Singh Panwar
Keyword(s):  
Pressure Sensor ◽  
Biomedical Applications ◽  
Circuit Simulation ◽  
Applied Pressure ◽  
Pressure Sensors ◽  
Cmos Technology ◽  
Current Mirror ◽  
Sensing Element ◽  
Pressure Sensing ◽  
Cmos Mems

This paper reports on the design and optimization of current mirror MOSFET embedded pressure sensor. A current mirror circuit with an output current of 1 mA integrated with a pressure sensing n-channel MOSFET has been designed using standard 5 µm CMOS technology. The channel region of the pressure sensing MOSFET forms the flexible diaphragm as well as the strain sensing element. The piezoresistive effect in MOSFET has been exploited for the calculation of strain induced carrier mobility variation. The output transistor of the current mirror forms the active pressure sensing MOSFET which produces a change in its drain current as a result of altered channel mobility under externally applied pressure. COMSOL Multiphysics is utilized for the simulation of pressure sensing structure and Tspice is employed to evaluate the characteristics of the current mirror pressure sensing circuit. Simulation results show that the pressure sensor has a sensitivity of 10.01 mV/MPa. The sensing structure has been optimized through simulation for enhancing the sensor sensitivity to 276.65 mV/MPa. These CMOS-MEMS based pressure sensors integrated with signal processing circuitry on the same chip can be used for healthcare and biomedical applications.

scholarly journals Sustainable Hydrogenation of Nitroarenes to Anilines with Highly Active In-Situ Generated Copper Nanoparticles

2020 ◽  
Author(s):  
Fatma Pelin Kinik ◽  
Tu Ngugen ◽  
Mounir Mensi ◽  
Christopher Ireland ◽  
Kyriakos Stylianou ◽  
...  
Keyword(s):  
Ambient Pressure ◽  
Hydrogenation Reaction ◽  
Hydrogen Gas ◽  
Proof Of Concept ◽  
Drug Molecules ◽  
Highly Active ◽  
The Earth ◽  
Earth Abundant ◽  
Stability Issues

<div> <div> <div> <p>Metal nanoparticles (NPs) are usually stabilized by a capping agent, a surfactant, or a support material, to maintain their integrity. However, these strategies can impact their intrinsic catalytic activity. Here, we demonstrate that the in-situ formation of copper NPs (Cu0NPs) upon the reduction of the earth-abundant Jacquesdietrichite mineral with ammonia borane (NH3BH3, AB) can provide an alternative solution for stability issues. During the formation of Cu0NPs, hydrogen gas is released from AB, and utilized for the reduction of nitroarenes to their corresponding anilines, at room temperature and under ambient pressure. After the nitroarene-to-aniline conversion is completed, regeneration of the mineral occurs upon the exposure of Cu0NPs to air. Thus, the hydrogenation reaction can be performed multiple times without the loss of the Cu0NPs’ activity. As a proof-of-concept, the hydrogenation of drug molecules “flutamide” and “nimesulide” was also performed and isolated their corresponding amino-compounds in high selectivity and yield. </p> </div> </div> </div>

scholarly journals B3.1 - Novel Silicon High Pressure Sensing Element

2009 ◽  
Author(s):  
Patrik Heinickel ◽  
Roland Werthschuetzky
Keyword(s):  
High Pressure ◽  
Sensing Element ◽  
Pressure Sensing

Pressure Sensing Fabric

2006 ◽  
Vol 920 ◽  
Author(s):  
Zhang Hui ◽  
Tao Xiao Ming ◽  
Yu Tong Xi ◽  
Li Xin Sheng
Keyword(s):  
Pressure Sensor ◽  
Fabrication Process ◽  
Sensing Element ◽  
Large Area ◽  
Pressure Sensing ◽  
Conductive Yarns ◽  
Flexible Pressure Sensor ◽  
Fabric Surface ◽  
The Cost ◽  
Resistive Grids

AbstractThis paper presents an approach for decoding the pressure information exerted over a piece of fabric by means of resistive sensing. The proposed sensor includes a distributed resistive grids constructed by two systems of orthogonally contacted electrical conductive yarns, with no external sensing element to be attached on the fabric. Since the conductive yarns serve as the sensing and wiring elements simultaneously, this design simplifies the fabrication process, reduces the cost and makes the production of large area flexible pressure sensor possible. The location of the pressure applied on the fabric can be identified by detecting the position where the change of the resistances occurs between two embroidered yarns. Meanwhile, the magnitude of the pressure can be acquired by measuring the variations of the resistance. In order to eliminate the “crosstalk” effect between adjoining fibers, the yarns were separately wired on the fabric surface.

Flexible hemispheric microarrays of highly pressure-sensitive sensors based on breath figure method

Nanoscale ◽  
2018 ◽  
Vol 10 (22) ◽  
pp. 10691-10698 ◽  
Author(s):  
Zhihui Wang ◽  
Ling Zhang ◽  
Jin Liu ◽  
Hao Jiang ◽  
Chunzhong Li
Keyword(s):  
Pressure Sensor ◽  
Pressure Sensors ◽  
Pressure Sensing ◽  
Sensing Range ◽  
Pressure Sensitive ◽  
Breath Figure ◽  
Breath Figure Method ◽  
Flexible Pressure Sensors

Flexible pressure sensors with interlocked hemispheric microstructures are prepared by a novel breath figure strategy. The subtle microstructure remarkably improves the sensitivity and pressure sensing range of the pressure sensor.

A bubble-based microfluidic gas sensor for gas chromatographs

Lab on a Chip ◽  
2015 ◽  
Vol 15 (1) ◽  
pp. 94-104 ◽  
Author(s):  
Ashrafuzzaman Bulbul ◽  
Hanseup Kim
Keyword(s):  
Gas Chromatography ◽  
Gas Sensor ◽  
Proof Of Concept ◽  
Sensing Element ◽  
Unique Relationship

This work is a new proof-of-concept bubble-based gas sensor for a gas chromatography system, which utilizes the unique relationship between the diameters of the produced bubbles with the gas types and mixture ratios as a sensing element.

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