35 research outputs found
A Fully-Integrated Semicircular Canal Processor for an Implantable Vestibular Prosthesis
Published versio
Separation of Enantiomers by Inclusion Gas Chromatography: On the Influence of Water in the Molecular Complexation of Methyl 2-Chloropropanoate Enantiomers and the Modified γ-Cyclodextrin Lipodex-E
A profound influence of water has previously been detected in the complexation of the enantiomers of methyl 2-chloropropanoate (MCP) and the chiral selector octakis(3-O-butanoyl-2,6-di-O-pentyl)-γ-cyclodextrin (Lipodex-E) in NMR and sensor experiments. We therefore investigated the retention behavior of MCP enantiomers on Lipodex-E by gas chromatography (GC) under hydrous conditions. Addition of water to the N2 carrier gas modestly reduced the retention factors k of the enantiomers, notably for the second eluted enantiomer (S)-MCP. This resulted in an overall decrease of enantioselectivity -ΔS,R(ΔG) in the presence of water. The effect was fully reversible. Consequently, for a conditioned column in the absence of residual water, the determined thermodynamic data, i.e. ΔS,R(ΔH) = -12.64 ± 0.08 kJ mol-1 and ΔS,R(ΔS) = -28.18 ± 0.23 J K-1 mol-1, refer to a true 1:1 complexation process devoid of hydrophobic hydration. Chirality 28:124-131, 2015
Null Point and Gain Adjustable Capacitive Microsensor
文中介绍一种可调零点和增益的电容式微型传感器。通过对MOS电流镜电路的深入探讨 ,给出了由MOS电流镜电路组成的零点和增益可调的电容式微型传感器测量电路 ;通过对传感器测量电路的动态过程仿真 ,明确了测量电路的最佳工作频率范围 ;通过对传感器测量电路静态过程的仿真 ,确定了这种测量电路的线性度和增益。由以上研究表明 ,零点和增益可调的电容式微型传感器具有线性度好和测量增益高的特点 ,并能有效地消除电路中的寄生电容对测量的影响 ,大大降低测量噪声。A type of capacitive microsensor whose null point and gain can be regulated is introduced here. The paper presents the measurement circuit of this microsensor through the application of the MOS current mirror circuit. It can clarifies the best working frequency range of the measurement circuit through the simulation of the dynamic and process of the circuit and get its linearity and gain through the simulation of the process of the circuit. Above researches have proved that such type of microsensor has good linearity and high gain and it can eliminate the influence of the stray capacitance on measurement, moreover it can decrease the noise of measurement
The Microsensor Technology Using to Identify the Initiation Time of Impact Induced Elastic Waves
[[abstract]]The microsensor technology was used here to identify the initiation time of an impact shock. The shock excitation caused by an impact sphere with a diameter of 4-6 minimeters could generate transient elastic waves in concrete structures. Such elastic waves with frequency above 100 kHz are the active emission sources for defect detection in the non-destructive testing (NDT) of concrete using transient elastic waves. In this paper, an impact sphere, which was packaged with a piezoresistive microsensor, was fabricated to verify this new idea. The microsensor after packaging has the maximum output voltage of 100 mV and the rise time less than 5 microsecond subjected to a sphere impact. The promising result of the initiation time experiment showed that the calibrated (short circuit) signal was left behind the microsensor signal for 40 nanoseconds.[[notice]]補正完畢[[incitationindex]]E
Real-Time Remote Monitoring of Temperature and Humidity Within a Proton Exchange Membrane Fuel Cell Using Flexible Sensors
This study developed portable, non-invasive flexible humidity and temperature microsensors and an in situ wireless sensing system for a proton exchange membrane fuel cell (PEMFC). The system integrated three parts: a flexible capacitive humidity microsensor, a flexible resistive temperature microsensor, and a radio frequency (RF) module for signal transmission. The results show that the capacitive humidity microsensor has a high sensitivity of 0.83 pF%RH−1 and the resistive temperature microsensor also exhibits a high sensitivity of 2.94 × 10−3 °C−1. The established RF module transmits the signals from the two microsensors. The transmission distance can reach 4 m and the response time is less than 0.25 s. The performance measurements demonstrate that the maximum power density of the fuel cell with and without these microsensors are 14.76 mW·cm−2 and 15.90 mW·cm−2, with only 7.17% power loss
Micropower front-end interface for differential-capacitive sensor systems
Accepted versio
Interface Circuits for Microsensor Integrated Systems
ca. 200 words; this text will present the book in all promotional forms (e.g. flyers). Please describe the book in straightforward and consumer-friendly terms. [Recent advances in sensing technologies, especially those for Microsensor Integrated Systems, have led to several new commercial applications. Among these, low voltage and low power circuit architectures have gained growing attention, being suitable for portable long battery life devices. The aim is to improve the performances of actual interface circuits and systems, both in terms of voltage mode and current mode, in order to overcome the potential problems due to technology scaling and different technology integrations. Related problems, especially those concerning parasitics, lead to a severe interface design attention, especially concerning the analog front-end and novel and smart architecture must be explored and tested, both at simulation and prototype level. Moreover, the growing demand for autonomous systems gets even harder the interface design due to the need of energy-aware cost-effective circuit interfaces integrating, where possible, energy harvesting solutions. The objective of this Special Issue is to explore the potential solutions to overcome actual limitations in sensor interface circuits and systems, especially those for low voltage and low power Microsensor Integrated Systems. The present Special Issue aims to present and highlight the advances and the latest novel and emergent results on this topic, showing best practices, implementations and applications. The Guest Editors invite to submit original research contributions dealing with sensor interfacing related to this specific topic. Additionally, application oriented and review papers are encouraged.
NASA SBIR abstracts of 1992, phase 1 projects
The objectives of 346 projects placed under contract by the Small Business Innovation Research (SBIR) program of the National Aeronautics and Space Administration (NASA) are described. These projects were selected competitively from among proposals submitted to NASA in response to the 1992 SBIR Program Solicitation. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 346, in order of its appearance in the body of the report. Appendixes to provide additional information about the SBIR program and permit cross-reference of the 1992 Phase 1 projects by company name, location by state, principal investigator, NASA Field Center responsible for management of each project, and NASA contract number are included