Patrizio Primiceri

Hardware Design and Software Development for a White LED-Based Experimental Spectrophotometer Managed by a PIC-Based Control System

In this paper, the design and testing of a PC-interfaced PIC-based control unit used to manage an absorption spectrophotometer, employing a white LED as light source, are described. LED technology allows to perform the absorption measurements reducing the analyte temperature variations and thus noise generation, which occur if a Xenon light source, usually employed, is used; also thanks to LED technology, the system results low cost, easy to use and with a low power consumption. The realized spectrophotometer can be used for atmospheric and industrial pollutant detection or for indoor air monitoring (e.g., in hospital rooms), being able to detect particulate matter, pesticides, volatile organic compounds as well as pollution produced by heavy metals. The realized system manages the different required functionalities, such as acquisition and processing, via firmware, of raw data provided by sensors, actuation of mechanical devices (stepper motor and solenoid valve), and synchronizing and controlling the data exchange between hardware sections, microcontroller, and PC. Both hardware and software sections were designed carrying out the appropriate tests to verify their proper operation. Results confirm the correct system functioning and interaction, via PC terminal, between user and the realized control unit.

Solar powered WSN for monitoring environment and soil parameters by specific app for mobile devices usable for early flood prediction or water savings

This paper describes the design and realization of a smart electronic system, based on a Wireless Sensor Network, for wide-area monitoring of availability level and rapid changes of the water presence in the monitored soil in order to guarantee flood prediction, water savings in the optimized farmland irrigation, waste reduction and optimal use of water resources where its availability is low. The designed sensor node, by means of the different embedded sensors, is capable of detecting environmental parameters, the solar radiation level and soil temperature and moisture (i.e. water volume content) values. The sensors communicate with a central processing unit located on board, used both as data processing unit and as Wi-Fi transceiver to receive/transmit the sensors data. The user near a sensor node, by a tablet or smartphone with an appropriate app, can collect information provided from sensors and share them with all users who use the same app on the Cloud, through peer to peer Wi-Fi or other internet connection.

Photo-Induced Ignition of Different Gaseous Fuels Using Carbon Nanotubes Mixed with Metal Nanoparticles as Ignitor Agents

ABSTRACT This article describes the photo-induced ignition process of multi-walled carbon nano-tubes (MWCNTs)/ferrocene mixtures by pulsed Xe lamps using programmable driving boards with adjustable parameters, such as variable flash rate and pulse’s energy/intensity. Varying the energy of incident light pulse, minimum ignition energy values were found as a function of mixture weight ratio, observing that a higher MWCNT amount with respect to metal nano-particles leads to lower ignition energy. The photo-induced ignition of CNTs mixed with nano-particles was then used in a properly realized experimental setup for triggering the combustion of CNT-enriched fuel mixtures. Different types of gaseous fuels mixed with air (CH4, liquid propane, and H2) were tested. The combustion process triggered by MWCNTs/ferrocene photo-ignition shows better performances, for all used gaseous fuels and for all tested air/fuel ratios, compared with those obtained by using a traditional spark plug. In particular, CNT-based photo-induced combustion evolves more rapidly with shorter ignition delays, higher peak pressure values, and a higher fuel burning rate as observed by reported experimental tests.

Photo-ignition process of multiwall carbon nanotubes and ferrocene by continuous wave Xe lamp illumination

This work aims to investigate and characterize the photo-ignition phenomenon of MWCNT/ferrocene mixtures by using a continuous wave (CW) xenon (Xe) light source, in order to find the power ignition threshold by employing a different type of light source as was used in previous research (i.e., pulsed Xe lamp). The experimental photo-ignition tests were carried out by varying the weight ratio of the used mixtures, luminous power, and wavelength range of the incident Xe light by using selective optical filters. For a better explanation of the photo-induced ignition process, the absorption spectra of MWCNT/ferrocene mixtures and ferrocene only were obtained. The experimental results show that the luminous power (related to the entire spectrum of the Xe lamp) needed to trigger the ignition of MWCNT/ferrocene mixtures decreases with increasing metal nanoparticles content according to previously published results when using a different type of light source (i.e., pulsed vs CW Xe light source). Furthermore, less light power is required to trigger photo-ignition when moving towards the ultraviolet (UV) region. This is in agreement with the measured absorption spectra, which present higher absorption values in the UV–vis region for both MWCNT/ferrocene mixtures and ferrocene only diluted in toluene. Finally, a chemo-physical interpretation of the ignition phenomenon is proposed whereby ferrocene photo-excitation, due to photon absorption, produces ferrocene itself in its excited form and is thus capable of promoting electron transfer to MWCNTs. In this way, the resulting radical species, FeCp2+∙ and MWCNT−, easily react with oxygen giving rise to the ignition of MWCNT/ferrocene samples.

Programmable driving boards of Xenon flash lamps for photo-ignition process of carbon nanotubes added to air/methane fuel mixture

This paper describes the design and testing of programmable driving boards for turning on Xenon flash lamps, with the aim to photo-ignite a gaseous fuel/air mixture enriched with Multi-walled carbon nanotubes with added metal impurities, makers of photo-ignition process. The key factor of realized electronic boards is the availability to adjust the triggering parameters of pulsed Xe lamps, allowing to fully characterize the combustion process under investigation. By using the designed PC-configurable boards in the realized experimental setups, the effects of Xenon light sources parameters such as pulse luminous intensity, flash-rate and time duration have been investigated in order to find the needed light energy/power to ignite MWCNT/Fe mixtures with different weight ratio (from 1:4 to 4:1). Experimental results show that lower energy thresholds are required with increasing MWCNTs amount respect to ferrocene.

Improved Photo-Ignition of Carbon Nanotubes/Ferrocene Using a Lipophilic Porphyrin under White Power LED Irradiation

The aim of this work is to investigate and characterize the photo-ignition process of dry multi-walled carbon nanotubes (MWCNTs) mixed with ferrocene (FeCp2) powder, using an LED (light-emitting diode) as the light source, a combination that has never been used, to the best of our knowledge. The ignition process was improved by adding a lipophilic porphyrin (H2Pp) in powder to the MWCNTs/FeCp2 mixtures—thus, a lower ignition threshold was obtained. The ignition tests were carried out by employing a continuous emission and a pulsed white LED in two test campaigns. In the first, two MWCNT typologies, high purity (HP) and industrial grade (IG), were used without porphyrin, obtaining, for both, similar ignition thresholds. Furthermore, comparing ignition thresholds obtained with the LED source with those previously obtained with a Xenon (Xe) lamp, a significant reduction was observed. In the second test campaign, ignition tests were carried out by means of a properly driven and controlled pulsed XHP70 LED source. The minimum ignition energy (MIE) of IG-MWCNTs/FeCp2 samples was determined by varying the duration of the light pulse. Experimental results show that ignition is obtained with a pulse duration of 110 ms and a MIE density of 266 mJ/cm2. The significant reduction of the MIE value (10–40%), observed when H2Pp in powder form was added to the MWCNTs/FeCp2 mixtures, was ascribed to the improved photoexcitation and charge transfer properties of the lipophilic porphyrin molecules.

Development and Characterization of a white Led-Based Spectrophotometer for UV/VIS Gaseous Pollutants Detection Employing Michelson Interferometer and an Optical Filtering System

Aim of this paper is the design of an absorption spectrophotometer based on LED technology presenting several advantages such as high luminous efficiency, reliability, long operating duration, low maintenance and low power consumption besides the reduction of analyte temperature variations which occur if Xenon light source is used. An optical filtering system was realized to detect analyte absorption for each wavelength range selected by proper optical filters; also to characterize filtered light beam in terms of its coherence length, thus correlating measured absorption spectrum with light source characteristics, the Michelson interferometer was used. Realized white LED-based spectrophotometer can be used to monitor air quality in hospital rooms or to detect atmospheric pollution deriving from vehicular traffic and different typology of pollutants (e.g., heavy metals deriving by industrial activities). A PC-interfaced control unit acquires and processes raw data provided by sensors (pressure, temperature, humidity, luminosity) and manages the optical filtering system motion by actuating a stepper motor. Whole system operation was tested and obtained results confirm the proper functioning and correct interaction, through PC terminal, between user and control unit.

An innovative approach for monitoring elderly behavior by detecting home appliance's usage

Detecting how elderly people interact with their surrounding environment, especially with domestic electrical appliances, is an important parameter to assess Mild Cognitive Impairments and frailty issues. This paper proposes an innovative approach for monitoring elderly behavior by detecting home appliances usage. It is based on an unobtrusive smart meter that periodically measures the global power consumption in the house, associated with some smart plugs for punctually monitoring specific electrical devices. This infrastructure has been implemented and validated within the Personal Data Capturing System of the City4Age Platform, where, joined with other provided monitoring systems, can feed risk detection algorithms with more accurate data. Summarizing, implemented system, although simple and at low cost, is able to combine data provided by designed power meter with those of smart meter plugs and, by means of implemented algorithms, to detect unusual elder behavior, moreover resulting reliable and accurate.

Photo-induced combustion of gaseous fuels using carbon nanotubes as ignitor agents: Driving and measuring systems, characterizations

Aim of this work is to describe the electronic driving system and the entire experimental setup realized in order to photo-ignite a gaseous fuel/air mixture enriched with Multi-wall carbon nanotubes (MWCNTs) with added metal impurities, makers of photo-ignition process. The realized electronic boards present different features such as variable flash brightness, pulse duration and high flash rate, allowing to fully characterize the combustion process under investigation. Varying the Xenon light sources parameters, the needed light energy/power to ignite MWCNT/Fe mixtures with different weight ratio was found. Experimental results show that lower energy thresholds are required with increasing MWCNTs amount respect to ferrocene. Then, the photo-induced ignition of CNTs mixed with nanoparticles was used in a properly realized experimental setup for triggering the combustion of different CNT-enriched air/fuel mixtures (CH4, Liquid Propane and H2). The combustion tests triggered by MWCNTs/ferrocene photo-ignition show better performances (shorter ignition delays, higher peak pressure values and a higher fuel burning rate), for all used gaseous fuels and all tested air / fuel ratios, compared with those obtained by using a traditional spark plug.

Experimental setup for calibration and optimized operation of Maximum Power Point Tracker applied to an innovative under-test photovoltaic system

This paper describes the operation and calibration modes for an experimental monitoring system of a photovoltaic (PV) plant with greater emphasis on the Maximum Power Point Tracker (MPPT). In order to optimize the energy production and therefore the economic convenience, it is very important that MPPT device works properly and that the measurement of PV electrical quantities is not affected by excessive errors. In this regard, the operation and related features of the MPPT3000, multifunction testing device used in the proposed measuring chain, are described in detail. More specifically, in addition to multi-parameter data acquisition system for PV plants, an experimental setup for calibration and operation check of MPPT devices has been developed, during their normal operation directly connected to the PV panels. From the collected data, it is observed a low measurement error (less than 1,5%) and verified the correct functioning of MPPT3000 devices, able to maximize the PV produced power even in case of abrupt variations in the solar irradiation level.