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Based on the classical Gram staining technique we created an adapted protocol so it could be used in bacterial suspensions for Gram positive and negative bacteria. The differences between these two types are determined by spectrophotometry. This is a rapid and low cost procedure to classify bacteria.
Electronic noses are systems that try to mimic the human nose. Currently gas sensors based on quartz crystal microbalance are frequently used to form such systems. These sensors have a sensing film deposited by the method of ultrasonic atomization. The sensor sensitivity is proportional to the square of the resonant frequency, therefore if it is desired to increase the sensitivity is necessary to...
In this paper we present the design of a mobile system for ethanol leak localization in the environment with wireless transmission to a computer. The system is composed of two operating modules: a communication module that transmits and receives information about the localization in a full-duplex wireless manner through a pair of transceivers, and a motion module that has an ultrasonic displacement...
In this paper a series of sensors based on SnO2 doped by impregnation with Pd, with a ratio of 1% to 5% were prepared. These sensors have shown good sensitivity for different alcohols (ethanol, n-butanol and 1-octanol). The characterization of the doped SnO2 was performed using N2 adsorption-desorption by the Brunauer-Emmett-Teller (SBET) surface area analysis, and Scanning Electron Microscopy (SEM)...
In this paper we present the implementation of a capacitive pressure sensor using interdigitated electrodes and a polymer cavity, the sensor functionality is based on the compression of a sealed cavity which changes the dielectric properties on top of two planar interdigitated electrodes (IDE). COMSOL was used to perform multiphysics simulations of the mechanical and electrical behavior of the sensor...
The study of transient response is necessary to characterize gas sensors in a dynamical system to be used in real time. The transient response to a step function is often used since it is the easiest stimulus to generate and provides useful information about the characteristics of the sensor. We implemented a system to measure the transient response which is based on a vapor generator of volatile...
Chitosan-gold nanocomposite has been synthesized by the Turkevich method and the final properties of nanocomposite have been investigated using electrical impedance spectroscopy, UV-vis spectroscopy, TEM and potentiometric measurements. We explore the possibility to detect copper ions using electrical impedance measurements in a linear range of 1–60 ppm, and using potentiometric measurements in a...
In this work, Aluminum Nitride (AIN) pedestal-type optical waveguides were fabricated and characterized. For the fabrication of these devices, a 0.6 μm-thick AIN film and a 1.5 μm-thick thermally grown silicon dioxide (SiO2) film were used as core and cladding layer, respectively. AlN films were deposited by RF reactive magnetron sputtering using parameter conditions studied previously. The pedestal...
Considerable research efforts have been devoted to the development of MEMS sensor packaging based on different material types (ceramic, plastic and metal). In this work, we describe the design, fabrication and test of a metal packaging with high reliability and low cost. The novelty of our research is on the packaging assembly by mechanical interference replacing the expensive plasma welding process...
Copper phthalocyanine particles were added to polymer solution of Polyacrylonitrile (PAN) 6.0 wt % and to Polyvinylidene Fluoride (PVDF) 20.0 wt %. Using electrospinning process we obtained composite PAN/CuPc and PVDF/CuPc fibers. As copper phthalocyanine has sensitivity to ammonia, it was possible depositing nanofibers on the substrate of a micro device constructed with an Piezoelectric Quartz Crystal...
Nowadays some surgery protocols includes Patient Empowerment as a key factor to enhance patient's mental state to achieve better surgical results. Since 2011, the “Fast Track Prosthetic Knee Project” at the Clinic Hospital of Barcelona (Spain) includes an educational session as patient empowerment previous to knee arthroplasty surgery. This paper presents a study performed in 41 patients measuring...
A non-invasive breath sensor that allows a continuous measurement of person's breathing, while they are making a physical effort is the target of this work. This work achieved the design, implementation and evaluation of a sensor for breathing measurement. After testing the sensor, we observed that it has a response in the presence of the CO2. This response was proportional to the quantity of the...
The main aim of this research is to find out the technical causes of the degradation of LTE (Long Term Evolution) service using the band of 700MHz with the simulator ns-3. We analyze how the QoS (Quality of Service) parameters change when more devices are aggregated to the base station and the scheduler allocates radio resources for each user. In this scenario, the QoS depends on the type of CQI Feedback...
In this paper we present the results of electronic transport calculations of an InAs/InP triple-barrier heterostructure that can be used as a gas sensor to recognize the vibrations of odorant molecules at room temperature. We modeled the nanostructure using a 1D approach, and calculated the transmission, density of states and the current vs. voltage characteristics using the non-equilibrium Green's...
The progress in the development of a piezoelectric immunosensor for the detection of a secretion protein (38 kDa) from Mycobacterium tuberculosis are described. A high affinity and specificity monoclonal antibody was obtained from a recombinant form of the target protein. This immunoreagent was employed for the development of a competitive ELISA, as a previous diagnostic test and reference assay for...
We present the design and fabrication process for an electrochemical “electronic nose” type sensor. This metal oxide based system focuses on the detection of ammonia as a possible sign of Ammonium nitrate based explosives, the main ingredients used by Armed Groups outside the law in Colombia for their Improvised Explosive Devices. The characterization of the conductivity variations of the zinc oxide...
In the bio-mining industry there are various compounds which need to be frequently monitored, one of which is iron, since its concentration can seriously affect the industrial process. This study describes the development of an electrochemical method of speciation and rapid quantification of iron in bio-mining processes conditions. Speciation and quantification was carried out in a flow injection...
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