Innovative Wearable Sensors Based on Hybrid Materials for Real-Time Breath Monitoring

This chapter will present the importance of innovative hybrid materials for the development of a new generation of wearable sensors and the high impact on improving patient’s health care. Suitable conductive nanoparticles when embedded into a polymeric or glass host matrix enable the fabrication of flexible sensor capable to perform automatic monitoring of human vital signs. Breath is a key vital sign, and its continuous monitoring is very important including the detection of sleep apnea. Many research groups work to develop wearable devices capable to monitor continuously breathing activity in different conditions. The tendency of integrating wearable sensors into garment is becoming more popular. The main reason is because textile is surrounding us 7 days a week and 24 h a day, and it is easy to use by the wearer without interrupting their daily activities. Technologies based on contact/noncontact and textile sensors for breath detection are addressed in this chapter. New technology based on multi-material fiber antenna opens the door to future methods of noninvasive and flexible sensor network for real-time breath monitoring. This technology will be presented in all its aspects

New Generation Wearable Antenna Based on Multimaterial Fiber for Wireless Communication and Real-Time Breath Detection

Smart textiles and wearable antennas along with broadband mobile technologies have empowered the wearable sensors for significant impact on the future of digital health care. Despite the recent development in this field, challenges related to lack of accuracy, reliability, user’s comfort, rigid form and challenges in data analysis and interpretation have limited their wide-scale application. Therefore, the necessity of developing a new reliable and user friendly approach to face these problems is more than urgent. In this paper, a new generation of wearable antenna is presented, and its potential use as a contactless and non-invasive sensor for human breath detection is demonstrated. The antenna is made from multimaterial fiber designed for short-range wireless network applications at 2.4 GHz frequency. The used composite metal-glass-polymer fibers permits their integration into a textile without compromising comfort or restricting movement of the user due to their high flexibility, and shield efficiently the antenna from the environmental perturbation. The multimaterial fiber approach provided a good radio-frequency emissive properties, while preserving the mechanical and cosmetic properties of the garments. With a smart textile featuring a spiral shape fiber antenna placed on a human chest, a significant shift of the operating frequency of the antenna was observed during the breathing process. The frequency shift is caused by the deformation of the antenna geometry due to the chest expansion, and to the modification of the dielectric properties of the chest during the breath. We demonstrate experimentally that the standard wireless networks, which measure the received signal strength indicator (RSSI) via standard Bluetooth protocol, can be used to reliably detect human breathing and estimate the breathing rate in real time. The mobile platform takes the form of a wearable stretching T-shirt featuring a sensor and a detection base station. The sensor is formed by a spiral-shaped antenna connected to a compact Bluetooth transmitter. Breathing patterns were recorded in the case of female and male volunteers. Although the chest anatomy of females and males is different compared, the sensor’s flexibility allowed recording successfully a breathing rate of 0.3 Hz for the female and 0.5 Hz for the male, which corresponds to a breathing rate of 21 breaths per minutes (bpm) and 30 bpm, respectively

Etude expérimentale et théorique des spectres d'émission et d'absorption VUV des molécules H2, D2 et HD

H2, HD and D2 molecules take a fundamental place in molecular physics, astrophysics and plasma physics. H2 is the most abundant molecule in the universe. The recent observations with high resolution of VUV transitions of this molecule and its isotope HD were carried out by the FUSE satellite in the range 90.5-118.7 nm. These observations make it possible to determine the intensity ratio HD/H2 of lines, considered as a new tool to evaluate the abundance ratio of D/H, which is known to be a tracer of the chemical evolution of the Universe. In addition, the H2, HD and D2 molecules are formed in the plasma of edge of the tokamaks and contribute to the radiative losses of the medium. Consequently, it is important to have spectroscopic data obtained in laboratory with high accuracy for a reliable exploitation of the results of observations or for a modeling of plasmas of fusion. The aim of this thesis is to carry out an experimental study of the absorption and emission spectra of the D2 and HD isotopes, with high resolution, in the VUV and to supplement it by a theoretical study of the excited electronic states involved in the observed transitions. Such a study had been carried out in our laboratory and had led to the realization of an atlas VUV in the range 70-170 nm for the H2 molecule. The emission spectra of HD and D2 are produced by Penning discharge source operating under low pressure, and are recorded in the spectral range 78 -170 nm using the high resolution vacuum spectrograph of 10 m (~150 000) of Meudon Observatory, either on photographic plates, or on image plates for measurement of intensities. The recorded spectra contain more than 20 000 lines. The wavelengths are measured with a precision of Δλ/λ= 10-6. The lines of the D2 molecules and H2 being present in the spectrum of HD, we initially start to carry out the analysis of the spectrum of D2, which consists to identify and to assign the lines to the electronic transitions between energy levels of the molecule. The present analysis is based on our theoretical calculations of the ro-vibrational energy levels of the excited electronic states and the transition probabilities from these states towards the energy levels of the fundamental state. In addition, we carried out a study of the absorption spectra of the HD and D2 molecules in the Laser Center LCVU of Amsterdam, using the two photons 1 XUV+1 UV laser spectroscopy. New wavelengths with a very high precision of Δλ/λ= 10-8 in the spectral range 99.9 -104 nm has been measured. These new wavelengths will constitute a data base of reference lines for the calibration of the molecular spectra, but their importance goes beyond the laboratory uses. Indeed, the new lines of HD measured by laser spectroscopy, added to the H2 lines already measured with a similar precision, will be used as references to study a possible cosmological variation of the masses ratio proton-to-electron μ= mp/me, by comparison with wavelengths of lines of H2 or HD observed in the absorption spectra of quasars at high red shift. This study requires the knowledge of the sensitivity coefficients of the wavelengths to the possible variation of μ, which we calculated by the resolution of coupled equations system for the electronic states B, B', C and D of the molecule H2 and HD for various values of μ.During my thesis, we were also interested in transitions between free-free and free-bound states of the H2 molecule. These transitions occur during the H-H collision forming a quasi-molecule and leads to the formation of satellites in the wing of the lines of the hydrogen atom. We carried out a quantum study of the quasi-molecular satellite of the Lymanβ line and calculated the profile of absorption of the satellite according to the temperature. This variation is an important tool for diagnosis for the determination of the characteristics of the atmospheres of dwarf white.Les molécules H2, HD et D2 occupent une place fondamentale en physique moléculaire, en astrophysique et en physique des plasmas. H2 est la molécule la plus abondante dans l'univers. Les récentes observations à haute résolution des transitions VUV de cette molécule et de son isotope HD ont été effectuées par le satellite FUSE dans le domaine 90.5 -118.7 nm. Ces observations permettent de déterminer le rapport d'intensités des raies HD/H2, considéré comme un outil nouveau pour évaluer le rapport d'abondances D/H, qui est connu pour être un traceur efficace de l'évolution chimique de l'Univers. Par ailleurs, les molécules H2, HD et D2 sont formées dans le plasma de bord des tokamaks et contribuent aux pertes radiatives du milieu. Par conséquent, il est indispensable de disposer de données spectroscopiques de haute qualité obtenues en laboratoire pour une exploitation fiable des résultats d'observations ou pour une modélisation réaliste des plasmas de fusion. L'objectif de cette thèse est d'effectuer une étude expérimentale à haute résolution des spectres d'émission et d'absorption des isotopes D2 et HD de l'hydrogène moléculaire dans le VUV et de la compléter par une étude théorique des états électroniques excités en relation avec les transitions observées. Une telle étude avait été effectuée dans notre laboratoire et avait abouti à la réalisation d'un atlas VUV dans le domaine 78-170 nm. Les spectres d'émission de HD et D2 sont produits par une source à décharge Penning opérant sous faible pression, et sont enregistrés dans la région spectrale 78 -170 nm à l'aide du spectrographe sous vide de 10 mètres à haute résolution (~ 150 000) de l'Observatoire de Meudon, soit sur plaques photographiques, soit sur des écrans phosphore photostimulables pour mesure d'intensités. Les spectres enregistrés contiennent plus de 20 000 raies. Les longueurs d'onde sont mesurées avec une précision de Δλ/λ= 10-6.Les raies des molécules D2 et H2 étant inévitablement présentes dans le spectre de HD, nous avons d'abord cherché à réaliser l'analyse du spectre de D2, qui consiste à identifier et à assigner les raies aux transitions électroniques entre des niveaux d'énergie de la molécule. Nous avons par ailleurs réalisé une étude en absorption des molécules HD et D2 au Centre Laser LCVU d'Amsterdam. Nous avons mesuré par spectroscopie laser à deux photons 1XUV+1UV, de nouvelles longueurs d'onde avec une précision inégalée de Δλ/λ= 10-8 dans le domaine spectral 99.9-104 nm permis par l'accordabilité du laser XUV. Ces nouvelles longueurs d'ondes constitueront une base de données de raies de référence pour la calibration des spectres moléculaires, mais leurs intérêts ne s'arrêtent pas au laboratoire. En effet, les nouvelles raies de HD mesurées par spectroscopie laser, ajoutées aux raies de H2 déjà mesurées avec une précision similaire, seront utilisées comme référence pour mettre en évidence une possible variation cosmologique du rapport de masse proton-électron μ= mp/me, par comparaison avec des longueurs d'onde de raies de H2 ou de HD observées dans les spectres d'absorption de quasars à grands déplacements vers le rouge. Cette étude nécessite la connaissance des coefficients de sensibilité des longueurs d'onde par rapport à la possible variation de μ, que nous avons calculés par la résolution d'un système d'équations couplées pour les états électroniques B, B', C et D de la molécule H2 et HD pour diverses valeurs de μ. Durant ce travail de thèse, nous nous sommes également intéressés à des transitions entre états libres-libres et états libres-liés de la molécule H2. Ces transitions se produisent lors d'une collision H-H formant une quasi-molécule et sont responsables de l'apparition de satellites dans l'aile des raies de l'atome d'hydrogène. Nous avons effectué une étude quantique du satellite quasi-moléculaire de la raie Lymanβ et calculé le profil d'absorption du satellite en fonction de la température. Cette variation est un outil important de diagnostic pour la détermination des caractéristiques des atmosphères des naines blanches

OBSERVATION OF TWO La(C3_3H2_2) ISOMERS FORMED BY DEHYDROGENATION OF PROPYNEOBSERVATION OF TWO La(C3_3H2_2) ISOMERS FORMED BY DEHYDROGENATION OF PROPYNE

Author Institution: Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055; Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055C-H bond activation of small hydrocarbons is of importance in chemistry and industrial applications. La(C$_3$H$_2$) was formed by the reaction of laser-ablated La atoms and propyne (C$_3$H$_4$) in supersonic molecular beams. Two isomers of La(C$_3$H$_2$) were detected for the first time by mass-analyzed threshold ionization (MATI) spectroscopy. From the MATI spectra, the two isomers exhibit origin bands at 42953(5) and 43609(5) cm$^{-1}$ and vibrational intervals of 425 and 535 cm$^{-1}$, respectively. They were identified as La(CCCH$_2$) formed from 1,3-dehydrogantion and La(HCCCH) formed by 3,3-dehydrogenation and were confirmed by measurements with deuterium substituted propyne (C$_3$D$_4$) as the precursor. The 1,3-dehydrogenated complex shows a higher ionization energy and larger metal-ligand stretching frequencies than the 3,3-dehydrogenated species. Based on DFT/B3LYP calculations, the electronic transitions responsible for the observed MATI spectrum of La(HCCCH)isomer is $^1$A $\leftarrow$ $^2$A,and that of La(CCCH$_2$)isomer is $^1$A$^{\prime}$ $\leftarrow$ $^2$A$^{\prime}$. C-H bond activation of small hydrocarbons is of importance in chemistry and industrial applications. La(C$_3$H$_2$) was formed by the reaction of laser-ablated La atoms and propyne (C$_3$H$_4$) in supersonic molecular beams. Two isomers of La(C$_3$H$_2$) were detected for the first time by mass-analyzed threshold ionization (MATI) spectroscopy. From the MATI spectra, the two isomers exhibit origin bands at 42959(5) and 43614(5) cm$^{-1}$ and vibrational intervals of 468/540 and 407/448 cm$^{-1}$, respectively. They were identified as La(CCCH$_2$) formed from 1,3-dehydrogantion and La(HCCCH) formed by 3,3-dehydrogenation and were confirmed by measurements with deuterium substituted propyne (C$_3$D$_4$) as the precursor. The 1,3-dehydrogenated complex shows a higher ionization energy and larger metal-ligand stretching frequencies than the 3,3-dehydrogenated species. The electronic transitions responsible for the observed MATI spectra of both isomers are $^1$A $\leftarrow$ $^2$A and will be discussed with aid of B3LYP/SDD calculations and Franck-Condon vibrational analysis

Validity of the Langevin capture model for charge exchange processes at thermal energies

International audienceA detailed coupled state quantum mechanical calculation using an adiabatic basis is analysed to investigate the validity of the Langevin model for very low energy charge transfer processes in ion-atom collisions. Taking as an example the N3+/H system, it is shown that the success of the Langevin model in describing the energy variation of the cross section is due to the accuracy of the phase averaging procedure in the double passage through the avoided crossing. On the other hand, the model does not yield the correct isotopic dependence of the cross sections. These can only be accurately determined by a coupled state calculation. At low thermal and sub-thermal energies less than 1 meV, the phase averaging procedure breaks down and quantum tunnelling effects become important. In these conditions, the energy variation of the cross section exhibits an appreciable departure from the Langevin model

VIBRATIONAL AND GEOMETRIC STRUCTURES OF La3{_3}C2{_2}O AND La3{_3}C2{_2}O+^+ FROM MASSE-ANALYZED THRESHOLD IONIZATION

Author Institution: Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055La${_3}$C${_2}$O is produced for the first time by laser vaporization in a pulsed cluster source and identified by photoionization time-of-flight mass spectrometry. Vibrationally-resolved ion spectra are obtained with mass-analyzed threshold ionization (MATI) spectroscopy. The adiabatic ionization energy of La${_3}$C${_2}$O is measured to be 30891(5) cm$^{-1}$. The spectra display several short vibrational progressions, and these progressions are associated mainly with La-La, La-C and La${_3}$C${_2}$O stretching excitations. The electron-spin multiplicities and molecular symmetries of La${_3}$C${_2}$O and La${_3}$C${_2}$O$^+$ are determined by combining the experimental measurements with ab initio calculations at MP2 level. Preliminary data analysis shows that the $^1$A$_1$ $\leftarrow$ $^2$A$_1$ transition is responsible for the observed MATI spectra. The cluster has C$_{2v}$ symmetry with La${_3}$C${_2}$O in a bi-pyramid structure and oxygen being attached to the La$_3$ plane

ULTRA-HIGH RESOLUTION SYNCHROTRON-BASED VUV SPECTROSCOPY USING A NEW FOURIER TRANSFORM SPECTROMETER: FIRST APPLICATION TO THE ABSORPTION SPECTRA OF THE RARE GASES.

De Oliveira, N.;Joyeux, D.; Phalippou, D.; Rodier, J.C.; Nahon, L.; Polack,F.,(to be published).De Oliveira, N.; Joyeux, D.; Phalippou, D.; Rodier, J.C.; Nahon, L.; Polack,F.; Vervloet, M. AIP Conference Proceedings, Vol 879K. Ito, K. Ueda, T. Namioka, K. Yoshino and Y. Morioka, J. Opt. Soc. Am. B5K. Yoshino. J. Opt. Soc. Am. 65L. Minnhagen, J. Opt. Soc. Am. 63E. B. Saloman, Phys. Chem. Ref. Data., 33Author Institution: Synchrotron SOLEIL, L'orme des Merisiers, St. Aubin Bp 48, 91192 Gif sur Yvette Cedex, France.A newly-developped Fourier Transform spectrometer (FTS), based upon a wave-front division interferometer, has recently been connected to the VUV beamline DESIRS on the French synchrotron facility SOLEIL. This instrument, unique in the world, using the pseudo-white coherent background continuum of an undulator, allows to perform ultra-high resolution absorption spectroscopy in the 140 - 40 nm spectral range}}, pp. 447-450 (2007).}, with a theoretical resolving power reaching 1000\,000 over the full range. With the intrinsic multiplex capability of FTS over a wide spectral range (typically 5 \% of the central wavelength) it should be a unique tool for the study of high lying electronic states of small diluted matter samples, in particular of atmospheric and astrophysical interest. As a first application and performance test of this new spectrometer, we have re-investigated at ultra-high resolving power ($\approx$ 700\,000) the VUV absorption spectrum of Ne, Ar, Kr and Xe rare gases involving Rydberg series in the spectral range \mbox{[54-104] nm}, using a windowless room-temperature absorption cell. The comparison of our first results with previous data for these rare gases}, 10 (1988).}}, 9 (1970).}}, 1185 (1973).}}. 33 (2004).} led to the identification of several new transitions between the ground state and the five Rydberg {\it{ns}},{\it{ns'}} and {\it{nd}},{\it{nd'}} series and to a refined determination of the autoionization parameters of the {\it{ns'}} and {\it{nd'}} series

Etude expérimentale et théorique des spectres d'émission et d'absorption VUV des molécules H2, D2 et HD

PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

DEHYROGENATION OF ETHYLENE: SPECTROSCOPY AND STRUCTURES OF La(C2_2H2_2) AND La(C4_4H6_6) COMPLEXES

Author Institution: Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055Hydrogen elimination is observed in the reaction of laser-ablated La atoms and ethylene (C$_2$H$_4$) in a pulsed molecular beam source. Dehydrogenated products, La(C$_2$H$_2$) and La(C$_4$H$_6$), are identified by time-of-flight mass spectrometry and studied by pulsed-field-ionization zero-electron kinetic energy spectroscopy and density functional theory calculations. La(C$_2$H$_2$) is determined as a triangle (C$_{2v}$) in the $^2$A$_2$ ground electronic state, where La binds with C$_2$H$_2$ in a two-fold mode ($\eta^2$). La(C$_4$H$_6$) is identified as a diligand species with La being sandwiched between C$_2$H$_2$ and C$_2$H$_4$, each in a two-fold binding mode, and the complex is in the $^2$A$_1$ ground electronic state. The adiabatic ionization energies of La($\eta^2$-C$_2$H$_2$) and La($\eta^2$-C$_2$H$_2$)($\eta^2$-C$_2$H$_4$) are measured to be 41174(5) and 39405(5) cm$^{-1}$, respectively. La$^+$-C$_2$H$_2$ and La$^+$-C$_4$H$_6$ stretching and C-H bending frequencies of the corresponding ions are also determined, and the vibrational assignments are confirmed with deuterated ethylene measurements