Tesi sul tema "Spectroscopie laser infrarouge"
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Weidmann, Damien. "Radiométrie hétérodyne infrarouge par diode laser accordable". Reims, 2002. http://www.theses.fr/2002REIMS005.
Testo completoPetitprez, Denis. "Spectroscopie infrarouge par laser à diode d'espèces réactives d'intérêt astrophysique". Lille 1, 1991. http://www.theses.fr/1991LIL10083.
Testo completoMacaleese, Luke. "Spectroscopie Infrarouge d'Intermédiaires Réactionnels Organométalliques". Phd thesis, Université Paris Sud - Paris XI, 2006. http://tel.archives-ouvertes.fr/tel-00180742.
Testo completoNous avons développé cette technique avec deux spectromètres de masse (un piège ICR et un piège quadripolaire de Paul) couplés au laser à électrons libres d'Orsay. Cette source infrarouge a l'intensité requise pour induire l'absorption résonante de multiples photons, et son accordabilité dans l'infrarouge (700-2200cm-1) a été exploitée pour caractériser une grande variété d'ions sélectionnés en masse, en particulier des systèmes organométalliques.
Une partie de cette thèse a été dédiée à la mise au point des deux montages expérimentaux, ainsi qu'à la modélisation des spectres IRMPD. Nous montrons que ceux-ci sont très semblables aux spectres infrarouges d'absorption calculés à l'aide de la fonctionnelle de la densité B3LYP. Nous montrons que l'IRMPD permet de caractériser le spin du métal et le mode de coordination d'un ligand polydentate dans des espèces organométalliques réactives très difficiles à caractériser en phase condensée.
La réaction d'allylation des amines par un alcool allylique, catalysée par un complexe du palladium, a été étudiée. Plusieurs cycles catalytiques sont proposés, et le spectre IRMPD des intermédiaires réactionnels observés permet, en caractérisant leur structure, de valider un cycle catalytique.
Moumdji, Souad. "Lasers à cristaux photoniques pour la spectroscopie infrarouge". Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2011. http://tel.archives-ouvertes.fr/tel-01068165.
Testo completoEl, Romh Jamila. "Spectroscopie laser des isotopologues de la molécule d’ammoniac dans le proche infrarouge". Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10128/document.
Testo completoThe ammonia molecule is one of the most abundant species in the atmosphere of solar planets and isotopic ratio 14N/15N is an important parameter to measure. Spectroscopy of ammonia was recently updated for 14NH3 by Sung et al [JQSRT, vol. 113, 11,1066 2012] in the range 6300-7000 cm−1 and included in HITRAN 2012 database.For the 15NH3 isotopologue, Lees et al [JMS, 251, no. 1-2, 241–251, 2008] assigned some transitions belonging to ν1 + ν3, ν1 + 2ν4 et ν3 + 2ν4 in the range 6412 to 6819 cm−1.Furthermore few line positions and strengths of transitions have been measured by Linsand al [App.Phy. B,102, 293–301, 2011.] with the goal of isotopic ratio measurement. In our work the spectroscopy of 14NH3 and 15NH3 have been extended with the help of an External Cavity Diode Tunable Laser spectrometer (ECDTLS) in the range 6369 to 6578 cm−1 and recordings at four temperatures (150K, 180K, 220K,296K).The spectra has been calibrated and each transition fitted to Voigt profile. Lines positions and strengths have been measured. The intensity ratio temperature dependence have been used to derive the energy of lower state for each transition. A specific treatment has been developed considering pairs of transitions intensities removing pressure dependence.For 14NH3 a transition list has been proposed including line position, strength and lower stateenergy. Compared with Sung et al 's work, the knowledge is increased by one third. For 15NH3 compared to the Lees et al 's work (240 lines), a line list including position and strength for 2604 transitions at room temperature has been proposed for the first time
Grouiez, Bruno Parvitte Bertrand Zéninari Virginie. "Applications des lasers à cascade quantique pulsés à l'étude de l'atmosphère". Reims : S.C.D. de l'Université, 2008. http://scdurca.univ-reims.fr/exl-doc/GED00000980.pdf.
Testo completoGillet, Jean-Christophe. "Spectroscopie laser infrarouge : application aux structures de biomolécules sélectionnées en sepctrométrie de masse". Paris 13, 2008. http://www.theses.fr/2008PA132019.
Testo completoThis manuscript presents a study of gas phase biomolecular systems obtained through the coupling of infrared spectroscopy and mass spectrometry. In the first part, we investigate cold neutral polar molecular systems using a technique that combines dipole-bound anion formation by Rydberg electron transfer and infrared spectroscopy, using a technique that combines dipole-bound anion formation by Rydberg electron transfer and infrared spectroscopy, using a home-made OPO laser. We obtain well-resolved IR spectra directly comparable to ab initio calculations. In a second part, we consider infrared spectroscopy of ions produced by electroscopy of ions produced by electrospray (ESI) and mass-selected in a quadrupole trap. We use infrared multiphoton dissociation (IRMPD) induced by the radiation issued from the free electron laseer CLIO. The studied systems are sequences of telomeres present at ends of chromosomes, small peptides as well as the 1-28 bêta-amyloid peptide involved in Alzheimer's disease. This experiment has less resolution than the first one but the experiments are conducted at the biologically-relevant temperature. The interpretation is then conducted with the help of structure calculations at the DFT level of theory and through quantum molecular dynamics. In the third part, we have established transferable local scaling factors provided for harmonic calculations at the DFT B3LYP and DFT B3PW91 levels in order to improve interpretation of infrared spectra
Jacquet, Patrick. "Interférométrie avec des lasers femtosecondes infrarouges". Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00598680.
Testo completoBELAIDI, HAKIMA. "Spectroscopie laser infrarouge dans un systeme a trois niveaux dans l'iode, pompe optiquement par laser, et d'interet metrologique". Paris, CNAM, 1995. http://www.theses.fr/1995CNAM0224.
Testo completoFlaud, Pierre-Marie. "Développement et caractérisation d'un spectromètre laser infrarouge par différence de fréquences : application à la spectroscopie infrarouge à très haute résolution". Paris 11, 2005. http://www.theses.fr/2005PA112285.
Testo completoFor laboratory studies and field measurements of atmospheric molecules, single-mode tuneable lasers are more and more used, in order to complete other instruments such as Fourier-transform spectrometers because of their limitations (in particular spectral resolution and signal-to-noise ratio that have an important impact on the accurate determination of molecular line parameters). We report here the development and characterization of a compact tuneable continuous-wave infrared laser, based on difference-frequency generation (DFG) using quasi phase-matching in periodically poled LiNbO3 (PPLN). Several 0. 1 microW of infrared radiation (tuneable in the 1800 à 3100 cm-1 range) are obtained using a diode-pumped Nd:YAG laser (output power about 800 mW at 1064 nm, linewidth 1 kHz) together with a tuneable external-cavity diode laser (output power about 10-50 mW in the 805-885 nm region, linewidth 1 MHz). Using this infrared DFG laser for absorption experiments of gas-phase molecules, both very high resolution (1 MHz) and a high signal-to-noise ratio (up to several 1000) can be achieved in measurement time of only a few minutes, as demonstrated using absorption spectra of N2O in different wavelength regions. Using this laser we have determined absolute intensities of infrared lines of NO2 (using a UV-visible set-up to measure the NO2 amounts) observing a systematic difference of about 5 % with respect to the HITRAN 2004 database. We have used the same laser for the first observation of collisional line-mixing between nuclear hyperfine components of HI lines (a phenomenon predicted over 20 years ago)
Garnache, Arnaud. "Etude et réalisation de nouveaux types de lasers proche infrarouge pour la spectroscopie d'absorption intracavité laser : dynamique des lasers fortement multimodes". Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10256.
Testo completoMaisons, Grégory. "Réalisation de source lasers monomodes innovantes émettant dans le moyen infrarouge : application à la spectroscopie". Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENY058.
Testo completoThis thesis work is focused on the top metal grating applied to the Quantum Cascade Lasers operating in the mid-infrared range of the electromagnetic spectrum. Physic phenomena involved in such structure have been understood thank to simple models which have been powerful tools to design devices. Results are confirmed by numerical studies based on the more complex S-matrix formalism. This study leads to several realizations: (i) The processing of single-mode sources with a precise control of the wavelength. The originality of these devices comes from the low loss interaction of the electromagnetic field with the metal. This configuration enables the processing of room temperature continuous wave distributed feedback (DFB) QCLs. (ii) The development of low divergence new devices, based on the combining of a first-order and a second order grating. (iii) The demonstration of the capability of a QCL optically coupled to a high finesse cavity (OF-CEAS : Optical-Feedback Cavity-Enhanced Absorption Spectroscopy) for the high sensitive molecular spectroscopy. All these developments have demonstrated the high maturity level of the top metallic grating, well adapted to the quantum cascade laser for their integration in spectroscopic systems
Ibrahim, Nofal. "Spectroscopie infrarouge à haute résolution par lasers accordables : applications à l'étude de composés d'intérêt atmosphérique". Paris 11, 2006. http://www.theses.fr/2006PA112259.
Testo completoHigh resolution infrared laser spectroscopy is a powerful technique for measuring a wide variety of atmospheric trace gases and for characterizing and quantifying of their physico-chemical properties. The use of tunable lasers provides the opportunity to scan over small spectral intervals with a very high spectral resolution and very high signal to noise ratio. The experimental determination of spectroscopic parameters using laser spectroscopy completes other techniques like Fourier transform spectroscopy. This work describes the development of three diode-laser spectrometers and the use of another two laser spectrometers tunable in the near- and mid-infrared regions for the measurement of atmospheric species. We have carried out four different studies: Measurements of H2O lines strengths, self- and air-broadenings coefficients in the 820 nm spectral region using an external cavity diode laser (ECDL) and a long-path absorption cell. Intercomparaison of the ozone absorption coefficients in the mid-infrared (10 micron) and ultraviolet (270-290 nm) spectral regions. Study of direct absorption and photoacoustic spectroscopy of NH3 in the 1550 nm region. The first measurement of the air-broadening coefficients of the HO2 radical using CRDS in the region around 1550 nm
Poisson, Antonin. "Spectroscopie adaptative à deux peignes de fréquences". Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00852102.
Testo completoJahjah, Mohammad. "Mise au point d'un système innovant de spectroscopie d'absorption multigaz par diodes lasers accordables dans le moyen infrarouge". Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20158/document.
Testo completoThe measurement of the pollutants is the subject since the late twentieth century especially in attention to protecting the planet. The gaseous species, specifically methane, present in the MIR, has strengths rays very intense, making the technique more sensitive.The detection technique of gas used during my PhD was chosen after an extensive comparison of different techniques belonging to the SDLA. This technique is the QEPAS technique. It has shown since its invention in 2002, a high sensitivity and selectivity in gas analysis. The light source used in the QEPAS is a tunable diode laser (Laser SC), thus making the technique more selectively, by varying the wavelength of emission as a function of injected current and / or control temperature to be located on a line desired to detect. The detector is QEPAS of quartz tuning fork (QTF). The latter is very sensitive to small force applied by the acoustic wave, which makes the technique very sensitive to low concentrations. Several steps are required characterization to determine the characteristics of the laser diode and the QTF. After choosing the laser diode and the QTF, ideal for spectroscopy, we pass to the evaluation of the technique QEPAS in gas analysis. The detection limits of methane obtained with the technique are QEPAS 0.8 ppmv and 400 ppbv to 2.3 microns with a Fabry-Perot laser and a photonic crystal laser, respectively, and 100 ppbv to 3.3 microns with a DFB laser.This work has provided a powerful technique (sensitive, selective, cheap ...) in gas analysis
Dobroc, Alexandre. "Etude et réalisation de dispositifs optiques à large couverture spectrale pour la détection multi-gaz à distance". Phd thesis, Ecole Polytechnique X, 2013. http://pastel.archives-ouvertes.fr/pastel-00959752.
Testo completoHerbin, Hervé. "Spectroscopie sélective de TiCl et NO : détection infrarouge ultrasensible de N2O et N2". Paris 11, 2005. http://www.theses.fr/2005PA112279.
Testo completoThis PhD thesis deals with the application of recent high resolution spectroscopic methods that are either selective or ultrasensitive. Spectroscopic parameters of stable and transient molecular species, difficult to reach otherwise, are determined. First, selective Fourier transform spectroscopy is used to characterize TiCl4/He and N2O/He plasmas. The spectrum of the whole emission of a plasma and spectra, which select a given class of molecules (for instance short-lived or ions) are simultaneously recorded. In particular, the rovibronic transition X - C of the 48Ti35Cl radical is observed around 3 µm. Its analysis has shown a very weak perturbation, which affects the C 4D1/2 state. Moreover, selective spectra of a N2O/He plasma, expected to only retain the ion lines, have revealed NO rovibronic transitions between the A, C, D and E Rydberg states. Under specific experimental conditions, a Doppler shift of the NO transitions, similar to the one of a positive ion, is observed. An interpretation of this unexpected phenomenon, highlighted for the first time for a neutral molecule, is proposed. Second, spectra with absorption lengths of several tens kilometers are recorded by coupling intracavity laser absorption spectroscopy (ICLAS) and time-resolved Fourier transform spectroscopy (TRFTS). Two different experiments have make it possible to probe, with high sensitivity, relatively wide infrared spectral ranges. Around 2. 5 µm, lots of weak intensity rovibrational transitions of the atmospherically relevant molecule N2O are identified and analysed. Unstable species created in a N2/He plasma are also detected for the first time around 1. 05 µm
De, Backer Andrée. "Étude d'un nouveau cristal laser et développement d'un laser de puissance dans le proche infrarouge pompé par diode laser". Lille 1, 2003. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2003/50376-2003-233.pdf.
Testo completoChevrollier, Martine. "Spectroscopie de réflexion sélective à une interface diélectrique/vapeur de césium : Observation de l'attraction Van der Waals de surface". Paris 13, 1992. http://www.theses.fr/1992PA132007.
Testo completoMulier, Maxime. "Mise en place d'un spectromètre laser infrarouge pour l'étude de la diffusion du CO2 gazeux hors du champagne et de quelques boissons effervescentes". Reims, 2009. http://theses.univ-reims.fr/sciences/2009REIMS034.pdf.
Testo completoRecent studies on champagne wine's CO2 bubbles attempt to draw the link between bubbles ascending in a champagne glass, CO2 gas diffusion from champagne and champagne flavour molecules freeing at the liquid/air surface. In order to progress in the understanding of the role of champagne bubbles in the CO2 diffusion mecanism, we have set up a direct absorption spectrometer based on near-infrared technology; relatively precise CO2 gas concentrations are measured and the mounting is thought to be adapted to a glass-shape change. Our open to the atmosphere spectrometer is based on a new generation laser diode emitting at 2,7 µm, centered at 3728 cm-1, resulting in an optimum absorption scale with a little pathlength. We have defined a protocol insuring a quite good measurements reproducybility with conditions very close to the champagne tasting conditions: thus, we paied attention to human activity "insulation", beverage temperature stabilisation, and champagne glass cleaning. First application of the sensor to a glass fullfilled with champagne showed the effect of temperature on CO2 diffusion with time. Also, second application of the sensor has been done to a glass fullfilled with some other sparkling beverages, each other having different initial CO2 concentrations; the solubility of CO2 in the beverage seems to influence CO2 diffusion with time. Finally, a mathematical model of the CO2 outgassing from a glass of champagne is required in order to complete the results and some elements are drawn in this work to describe the diffusion by mass convection at the free surface
Mandon, Julien. "Spectroscopie de Fourier par peignes de fréquences femtosecondes". Phd thesis, Université Paris Sud - Paris XI, 2009. http://tel.archives-ouvertes.fr/tel-00519027.
Testo completoPoullet, Emmanuelle. "Analyse et quantification de Composés Organiques Volatils (COV) par spectroscopie infrarouge à l'aide d'une source laser à différence de fréquences". Littoral, 2002. http://www.theses.fr/2002DUNK0087.
Testo completoAtmospheric pollution is of main concern. In this context we are interested in analysis and quantification of volatil organic compounds (VOC) using spectroscopy in the infrared. Many of these molecules exhibit signatures, usually used for their identification and quantification, in this spectral region. An infrared spectrometer based on difference frequency generation has been developed in our laboratory. It has the advantage of being continuously tunable between 8. 8 and 19 µm. Several absorption cells were used for varying the interaction length from 0. 11 to 106 m, which enables optimisation of the recorded signal for each concentration. This spectrometer enabled the recording of several VOC absorption spectra such as ethylene, toluene and benzene. Researches have been realised on spectroscopic parameters of the 8₂,₇ ← 8₁,₇ transition of the V7 vibration band of ethylene. In the first investigation, we determined the line intensity and broadening coefficient for different perturbing gazes. A method for quantification of heavy molecules such as toluene has been developed. The relevance of this method, called "absorbances correlation", is studied using ethylene molecule. Moreover, this method is available for simultaneous detection of several components whose signatures overlap. It has been used for a mixture of toluene and carbon dioxide
Humbert, Bernard. "Développements expérimentaux et théoriques en spectrométries infrarouge et Raman : application à l'étude des silices divisées". Nancy 1, 1991. http://www.theses.fr/1991NAN10028.
Testo completoRaynaud, Fabrice. "Perfectionnement d'un spectromètre infrarouge à diode laser : analyse de la bande v16 du 1-1 difluoroéthane en jet supersonique". Lille 1, 1997. http://www.theses.fr/1997LIL10231.
Testo completoGrouiez, Bruno. "Applications des lasers à cascade quantique pulsés à l’étude de l’atmosphère". Reims, 2008. http://www.theses.fr/2008REIMS025.
Testo completoThis thesis work presents atmospheric applications using Quantum Cascade lasers (QCL) emitting in mid-Infrared. Parts I & II present the context of my thesis work, the principle of QCL and the study of _1 band of SO2 around 9 μm by continuous wave operation QCL. In the third part, we present the first method we have employed to command the laser which is also the most popular in pulsed operation. This one consists of operating the laser with a short pulse duration (_ 10 ns). This method has been applied to the study of NH3 and has put in evidence many troubles which limit considerably the interest in spectroscopic applications. In the fourth part, the command of QCL using long pulses (> 500 ns) is presented. We demonstrate the possibility to record an intra-pulse spectrum in about one microsecond. This technic has been applied to the study of SO2 in 9 μm region and the results have been compared with results obtained by continuous wave operation. The conclusion of our previous works (in parts III & IV) drove us to consider a third way with intermediatesize pulse width (< 100 ns). This is presented in the fifth part. This method has solved many troubles of this kind of laser and furthermore it has put into the light the most importants points about "rapid passage" effects
Depiesse, Cédric. "Spectrométrie ultrasensible par transformée de Fourier couplée à un montage laser intracavité: application à l'étude des niveaux de vibration-rotation de l'acétylène". Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211007.
Testo completoNous avons ensuite couplé le dispositif ICLAS avec un spectromètre à transformée de Fourier en synchronisant l’acquisition des données avec les impulsions. L’avantage de ce couplage réside dans l’obtention d’une technique à la fois très sensible grâce à l’ICLAS mais aussi possédant une haute résolution et une large couverture spectrale grâce au spectromètre. La réalisation de ce dispositif est décrite dans la première partie de ce travail.
Nous avons ensuite appliqué ce dispositif instrumental à l'étude des molécules C2HD et 13C12CH2. L’analyse des spectres enregistrés est détaillée dans la seconde partie de ce travail. Celle-ci inclut également une introduction à la description théorique des niveaux d’énergie de vibration-rotation adaptée au cas de la molécule d’acétylène. L’analyse est axée principalement sur la structure rotationnelle et l’identification vibrationnelle des nouvelles bandes observées grâce aux performances du nouveau spectromètre. Les premières étapes vers la construction d’un modèle rovibrationnel global pour les deux molécules étudiées sont également décrites.
Doctorat en sciences, Spécialisation physique
info:eu-repo/semantics/nonPublished
Duan, Chuanxi Bogey Marcel Liu Yuyan. "Spectroscopie rovibronique et rotationnelle de molécules réactives". [S.l.] : [s.n.], 2003. http://www.univ-lille1.fr/bustl-grisemine/pdf/extheses/50376-2003-273-274.pdf.
Testo completoThèse en co-tutelle. N° d'ordre (Lille 1) : 3285. Texte de la thèse en chinois. Articles en anglais en annexe. Résumé en chinois, français et anglais. Bibliogr. p. 125-126.
Amir, Wafa. "Spectroscopie infrarouge résolue en temps pour l'étude de la dynamique femtoseconde du proton en phase liquide". Phd thesis, Ecole Polytechnique X, 2003. http://pastel.archives-ouvertes.fr/pastel-00000700.
Testo completoBenzerhouni, Kaddour. "Spectroscopie d'absorption de l'ammoniac et étude du laser (¹⁵NH₃+ N₂) à inversion de population". Paris 11, 1988. http://www.theses.fr/1988PA112097.
Testo completoThis work is a study of the ammonia molecule under its two isotopic species ¹⁴ NH₃ and ¹⁵NH₃. The two following topics are developed:On one hand, the spectroscopic aspect of the molecule is studied related to the spectral profile of the absorption tine. On the other hand, we perform ammonia laser working in mid infrared by optical pumping with a CO2 laser. In chapter I all spectroscopic data about this ammonia molecule are reported, especially the -√2 absorption band in the 10,5 µm spectral range. This band gives rise to a lot of quasi coïncidences with the emission lines of the C02 for the two isotopic species ¹⁴ NH₃ and ¹⁵NH₃. In chapter ll, the profile of the absorption lines is studied. The intensities and line-width of some tines have been measured using a diode laser spectrometer. The way to determine collisional line-width is described. Several methods are used to determine intensities. Advantages and disadvantages of each method are discussed. In chapter Ill, ail previous works about the ammonia laser are recalled, especially the off-resonant optical pumping giving rise to the powerful Raman laser. We report the work made with this "Raman laser" at 12,08 μm, in order to study the absorption profile of the sP(7,0) line of ammonia. The results obtained with ¹⁴ NH₃ specie self-broadened, or with buffer gases, N₂ or He, are reported and discussed. In chapter IV, we describe our work about the resonant optical pumping on ¹⁵NH₃ in a ring configuration. The study, realization and optimization for the population inversion laser (¹⁵NH₃+ N₂) giving a laser line at 11,76 μm, is developed. The main experimental results about the properties of this laser are reported. A rate equation model is established for the small signal gain. An analysis of the gain according to the different parameters of the laser gives a good comparison with experimental results
Rusinek, Eric. "Spectroscopie subdoppler par source laser infrarouge : évolution d'un prototype vers un spectromètre automatisé à large gamme d'accord en fréquence". Lille 1, 1997. http://www.theses.fr/1997LIL10138.
Testo completoDusanter, Sebastien. "Application des diodes laser infrarouges accordables à deux problématiques : la métrologie de polluants : la cinétique des réactions élémentaires". Lille 1, 2002. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2002/50376-2002-247.pdf.
Testo completoMammez, Dominique. "Détection de molécules gazeuses d’intérêt atmosphérique par spectrométrie infrarouge avec laser à cascade quantique largement accordable". Thesis, Reims, 2013. http://www.theses.fr/2013REIMS003/document.
Testo completoAs the study of the atmosphere is growing strongly in response to environmental issues, the needs in terms of laser sources for spectroscopy of complex molecules require the development of widely tunable sources. The PhD work presented in this manuscript is focused on the implementation of quantum cascade lasers in external cavity (EC-QCL). Part of this work deals with the characterization of a commercial EC-QCL source and its application to gas detection by photoacoustic spectrometry. Measurements were performed on carbon dioxide in exhaled air and butane. The central part of this thesis consists in the development of ECQCL sources based on quantum cascade laser chips from III-V Lab. The aim is to obtain widely tunable sources that can be used for the detection of complex molecules. This includes simulation, design and implementation of external cavity systems. Two EC-QCL sources were implemented. The first one is a pulsed laser emitting around 4,5μm. The second one emits around 7,5μm and is operated at room temperature in continuous wave mode. This laser was used to record the spectra of acetone and phosphoryl chloride
Elhanine, Mohammed. "Spectroscopies sélectives par transformation de Fourier et laser à diodes : étude infrarouge à haute résolution d’espèces moléculaires transitoires". Paris 11, 1989. http://www.theses.fr/1989PA112169.
Testo completoThe infrared emission of an H2S plasma has been recorded at high resolution over a wide spectral range using a Fourier transform interferometer. The plasma is excited by a radiofrequency discharge in a flow reactor at low pressure. Four vibration-rotation bands of the ground electronic state (X2Π) of the SH radical have been observed, each with the expected anomalous weak P branch intensity. This effect can be explained by a strong vibration-rotation Coriolis coupling. In the same spectrum, vibration-rotation bands of SH- have also been identified. This is the first observation of a negative ion by Fourier transform spectroscopy. The existing molecular constants of SH- have been improved in a least squares fit. For improving the detection of paramagnetic transient species, two new selective methods for use with high resolution infrared spectroscopy have been developed. These techniques, Zeeman modulation and polarization modulation, are essentially based on magneto-optics properties. They have been successfully demonstrated with both Fourier transform and diode laser spectrometers. The results obtained with the NO radical illustrate the selectivity of these methods. Comparison of the two shows that polarization modulation is the more sensitive. Particular attention is paid to the interpretation of the observed lines shapes, which have been accurately simulated. In conclusion, it is hoped that the selective detection techniques described here will be useful for the discovery of new paramagnetic transient species
Cheikh, Monia. "Spectroscopie infrarouge à haute résolution et photodissociation à l'aide d'un laser à CO d'une molécule asymétrique : le chlorure de nitrosyle". Paris 11, 1988. http://www.theses.fr/1988PA112085.
Testo completoONCI est une toupie asymétrique §table en phase ga,euse. Son énergie de dissociation est relativement basse vers 1300 cm⁻ ᴵ ce qui permet d'envisager sa photodissociation rnultiphotonique ou par tranfert VV. Elle possède trois vibrations fondamentales v ₁ , v₂ et v ₃. V ₁ située à 1800 cm⁻ ᴵ et associée à la vibration NO, peut donner lieu à des coïncidences avec l'émission du laser à CO. V₂et et v ₃sont beaucoup plus basses à 596 et 332 cm⁻ ᴵ, ce qui donne une forte densité de niveaux à haute énergie vibrationnelle. L'irradiation de ONCI par le laser à CO utilisé en multiraies, la porte dans les états excités du mode v ₁. Le couplage éventuel entre les niveaux rotationnels des autres modes de combinaison peut conduire la dissociation de ONCI. L'étude par spectroscopie infrarouge à haute résolution de ONCI est nécessaire. En effet, l'étude de la bande v ₁ nous a permis de connaître les coincidences des raies d'absorption de ONCI avec celles émises par le laser à CO. Afin d'améliorer ces coincidences, on élargit les raies de ONCI par un "Puffer" : l'Argon. On a ausi interprété la bande v ₁ + v ₃ qui se prêterait à une excitation par le laser à co₂. Cette étude spectroscopique nous a permis de déterminer des constantes rotationnelles des états (100), (101) et (011). On a monté le dispositif expérimental nécessaire à l'expérience de photodissociation de ONCI. L'excitation infrarouge du mélange ONCI-Ar, par le laser à CO utilisé en multiraies conduît à la dissociation. Les produits sont analysés par spectroscopie d'absorption infrarouge à l'aide d'une diode laser. On a observé la croissance de l'absorption de NO
Mayet, Céline. "Spectromicroscopie infrarouge à l'échelle nanométrique : Application à l'étude d'objets biologiques". Paris 11, 2010. http://www.theses.fr/2010PA112272.
Testo completoInfrared spectromicroscopy is an extremely powerful analytical technique able both to characterize chemical compounds by their absorption bands and to locate them spatially through a microscope. The AFMIR facility (Atomic Force Microscope InfraRed) is a new and original technique of sub-wavelength infrared spectromicroscopy that combines a tunable pulsed infrared laser and an atomic force microscope (AFM). By using the photothermal effect, it allows the experimenter to do « ultra local» infrared spectroscopy and to achieve chemical mappings with a very good lateral resolution (a few tens of nanometers). During this thesis, a modeling work was conducted to estimate the spatial resolution of the AFMIR technique and to understand all involved physical phenomenons. Parallel to this theoretical study, a stage of instrumental development was necessary to adapt the facility to studies in liquid medium and to allow analysis of live biological samples. Finally, three scientific questions were addressed: infection of the bacterium Escherichia coli by the phage T5, production of the polymer PHB by the bacterium Rhodobacter capsulatus and identification of the organelle target for a hormone in a hormone independente breast cancer cellline. All results were confirmed with measurements by transmission electron microscopy and conventional infrared absorption spectroscopy. The AFMIR technique is now operational to be offered to other researchers in the field of biology
Cheikh, Monia. "Spectroscopie infrarouge à haute résolution et photodissociation à l'aide d'un laser à CO d'une molécule asymétrique le chlorure de nitrosyle /". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376038787.
Testo completoDuan, Chuanxi. "Spectroscopie rovibronique et rotationnelle de molécules réactives". Lille 1, 2003. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2003/50376-2003-273-274.pdf.
Testo completoCousin, Julien. "Instruments de Mesure Multi-Polluants par Spectroscopie Infrarouge basés sur des Lasers Fibrés et par Génération de Différence de Fréquences : Développement et Applications". Phd thesis, Université du Littoral Côte d'Opale, 2006. http://tel.archives-ouvertes.fr/tel-00124729.
Testo completoTran, Dang Bao An. "Widely tunable and SI-traceable frequency-comb-stabilised mid-infrared quantum cascade laser : application to high precision spectroscopic measurements of polyatomic molecules". Thesis, Sorbonne Paris Cité, 2019. http://www.theses.fr/2019USPCD060.
Testo completoThe thesis consists in developing a high-resolution mid-infrared spectrometer traceable to primary frequency standards and providing a unique combination of resolution, tunability, detection sensitivity and frequency control. A quantum cascade laser (QCL) emitting at 10.3 µm is phase locked to an optical frequency comb stabilized to a remote 1.55 µm ultra-stable reference developed at LNE-SYRTE, monitored against primary frequency standards and transferred to LPL via an active noise compensated fibre link. This results in a 0.1 Hz QCL linewidth, a stability below 10⁻¹⁵ at 1 s and an uncertainty on its absolute frequency below 4 × 10⁻¹⁴. Moreover, the setup allows the QCL to be widely scanned over 1.4 GHz while maintaining the highest stabilities and precision. This QCL was used to carry out saturated absorption spectroscopy of several molecules in a compact multipass cell. We demonstrated statistical uncertaintyon line-center frequencies at the kHz level and sub-10 kHz systematic uncertainty. We have recorded several singular K-doublets and many rovibrational transitions of methanol, in particular weak transitions and weak doublets - unreported so far. Precise parameters modelling trioxaneh ave been determined with only a few tens of rovibrational transitions recorded at unprecedented accuracy. The quadrupole hyperfine structure of an ammonia transition has been resolved for thefirst time. This setup constitutes a key element for the project aiming at the first observation of parity violation in molecules currently held at LPL, and, more generally, for various fields of physics, from atmospheric and interstellar physics to fundamental physics beyond the standard model
Delbarre, Hervé. "Etude de l'origine des instabilités spectrales dans un laser à électrons libres en régime compton". Lille 1, 1993. http://www.theses.fr/1993LIL10127.
Testo completoSIMONDI, TEISSEIRE BEATRICE. "Cristallogenese, spectroscopie optique et proprietes laser dans le proche infrarouge de materiaux de type melilite dopes yb, er et yb-er". Paris 6, 1996. http://www.theses.fr/1996PA066757.
Testo completoTigréat, Pierre-Yves. "Synthèse et étude optique de cristaux dopés Dy3+ et codopés Tm3+ et Yb3+ pour applications laser dans le moyen infrarouge". Caen, 2001. http://www.theses.fr/2001CAEN2046.
Testo completoAndrieux, Emeline. "Réalisation d’un oscillateur paramétrique optique stabilisé en fréquence et accordable continûment sur 500ghz pour la spectroscopie infrarouge". Thesis, Paris, CNAM, 2011. http://www.theses.fr/2011CNAM0796/document.
Testo completoWe developed a singly-resonant optical parametric oscillator (SRO) based on a nonlinear crystal of 5%-ppMgCLN congruent lithium niobate chip and pumped at 1064 nm by an extended cavity diode laser widely tuneable from 1050 to 1070 nm injecting a 10 W Yb-fiber amplifier. It generates an idler wave between 3 and 4 µm and a signal wave between 1450 and 1650 nm. The SRO cavity is stabilized to the top of a Fabry-Perot transmission fringe. We then demonstrated a mode-hop-free idler tuning range of 500 GHz. This broad continuous tunability could be used for multi-species high resolution spectroscopy in the mid-infrared. Moreover, we have revisited the plane waves SRO theory, whose analytical solutions were given for the first time in 1969 by Kreuzer in the form of a transcendental equation, using a very powerful perturbative method which takes into account the depletion of the pump. We were able to determine the input-output relations of SRO in the form of very simple explicit relationships, showing that the output powers are proportional to the cubic root of the pump power
Girard, Véronique. "Spectroscopie d’absorption ultrasensible dans l’infrarouge des molécules d’intérêt astrophysique N2 et C2H2". Paris 11, 2007. http://www.theses.fr/2007PA112243.
Testo completoThe work presented in this thesis concerns the development and application of a new method of high-resolution gas phase infrared spectroscopy based on the coupling of the time-resolved Fourier transform spectroscopy (TRFTS) and the intracavity laser absorption spectroscopy (ICLAS). This coupling allows combining the qualities of these two techniques: high sensitivity, Doppler-limited resolution and broad spectral domain. An ICLAS-TRFTS experience based on a Cr4+:YAG solid-state laser was set up. By tuning the laser emission, this one can be put inside an atmospheric window where the absorption by atmospheric water molecules is weaker. Currently, tunability has been acquired under vacuum between 1. 442 and 1. 557 µm. Nitrogen and acetylene are molecules of astrophysical interest since they are part of the atmosphere of numerous planets and satellites. Thanks to an ICLAS-TRFTS experience based on a VCSEL-type surface emitting semiconductor laser, spectra from nitrogen plasma have been recorded between 1. 028 and 1. 054 µm. Lines of the (0-0) band of the B 3Πg – A 3Σu+ system of the 14N15N isotopologue have been reported for the first time, as well as lines from (4-5) and (5-6) bands of the B 3Πg – A 3Σu+ system and (2-0) band of the B' 3Σu- – B 3Πg system of the 14N2 isotopologue. Then, thanks to an ICLAS-TRFTS experience based on Cr2+:ZnSe solid-state laser, acetylene spectra have been recorded between 2. 424 and 2. 561 µm. This represents the extreme limit reached by ICLAS towards the infrared domain. Besides, two cold bands ν1+ν41 and ν3+ν51 of the 12C13CH2 isotopologue have been reported for the first time
Boudjaadar, Djamel. "Spectroscopies infrarouges laser et par T. F. Des espèces instables SiH et NH : détermination des constantes moléculaires de l'état électronique fondamental ³sigma⁻ de NH". Paris 11, 1985. http://www.theses.fr/1985PA112296.
Testo completoGolebiowski, Dariusz. "High resolution FTIR spectroscopy using a femto-OPO laser source and cavity enhanced absorption". Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/221150.
Testo completoDoctorat en Sciences
info:eu-repo/semantics/nonPublished
Duplouy, Lucie. "Etude spectroscopique UV-vis et infrarouge de la photoséparation de charges de molécules adsorbées dans des matériaux zéolithiques de type MFI : cas de dérivés cyano-aromatiques et du trans-stilbène". Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R066.
Testo completoThe particular environment within the porous structure of zeolites allows these materials to act as micro-reactors to optimize the photoreactivity of adsorbed molecules. In this context, we report the reaction mechanisms occurring after photoionization of t-stilbene confined into crystals of ZSM-5 zeolites of different sizes and morphologies. In the micro and nanocrystals of ZSM-5, the photoinduced cation radical evolves into a very stable charge transfer complex (CTC), formed by the ejection of an electron and stabilized by a compartmentalization process. In nanosheets, the cation radical is the stabilized species because the ejected electron cannot be trapped far enough from the cation radical to allow the formation of the CTC. Finally, in nanosponges, CTC is not formed and the lifetime of the radial cation is reduced to a few hundred µs. The case of anionic species formation was also studied. Thus, in aluminized MZSM-5s (M = H+, Na+ and Cs+), the photoexcitation of the incorporated 1,4-dicyanobenzene leads to the formation of an anion radical (RA) thanks to the zeolite donor character, whereas in silicalite-1, the Al-free MFI analogue, this reaction does not occur. In particular, nanosecond UV-vis spectroscopy highlighted the key role of aluminum and the influence of the charge-compensating cation on the lifetime of the RA. The activation energies required for the recombination of the electron of the anion radical with the positive electron hole created in the zeolite were determined and discussed. Finally, the work carried out on the study of the primary steps of charge separation processes in the case of the 9,10-dicyanoanthracene (DCA) molecule crystallized on the surface of ZSM-5 zeolites by photon counting (TCSPC) and femtosecond IR absorption spectroscopy techniques showed the ultrafast and quasi-simultaneous formation of the excited S1 singlet state, a state of charge transfer and excimer forms whose distribution depends on the polymorphism of the DCA crystal on the external surface of the zeolite. (Co-funding Region Hauts-de-France/Université de Lille)
Simeni, Simeni Marien. "Quantum cascade laser absorption studies of nitric oxide production by nanosecond pulsed discharges in air and in combustible mixtures". Thesis, Châtenay-Malabry, Ecole centrale de Paris, 2015. http://www.theses.fr/2015ECAP0033/document.
Testo completoAtmospheric pressure plasmas have numerous potential applications. These applications include for instance biomedicine, material processing, environmental biodecontamination and plasma-assisted combustion. The versatility of plasma discharges results from their ability to produce high quantities of active species without increasing the temperature of the gas appreciably. Nanosecond Repetitively Pulsed discharges (NRP) have received great attention owing to their capacity to generate high electron densities, which lead to the creation of a high density of active species such as atomic oxygen. Optical Emission Spectroscopy (OES) showed that excited nitric oxide (NO) was released by NRP discharges in air or in air/fuel mixtures.Although NRP discharges have already been the object of several investigations, the kinetic mechanisms of NO production by NRP discharges at atmospheric pressure remain somewhat unclear. This is one of the motivations for the investigations conducted in this thesis. In addition, NRP discharges were found to produce large amounts of atomic oxygen, which is of great interest for applications such as plasma-assisted combustion. It was shown in particular that thanks to this high production of active species, NRP discharges can effectively stabilize lean flames at atmospheric pressure. However, the production of NO in NRP discharges and in plasma-stabilized flames remains to be investigated. This is the second purpose of this thesis.Absolute and in-situ NO density measurements in atmospheric pressure plasma or/and flame environments are very challenging. Fluorescence-based techniques such as Laser Induced Fluorescence (LIF) require complex calibration methods. These techniques also require the knowledge of the quenching rates of the excited states (particularly at atmospheric pressure), which strongly depend on the temperature, density and nature of the species and can be very different for plasma or/and flame environments. Other techniques, such as chemiluminescence probe sampling also have quenching and calibration issues, and ex-situ UV and IR absorption-based gas analyzers can lead to errors, in particular for radicals.In this study, we developed Quantum Cascade Laser Absorption Spectroscopy (QCLAS) for in-situ nitric oxide absolute density measurements in open-air and in combustion environments. This technique overcomes the difficulties of the previous ones by using high-resolution (10-3 cm-1) rotational-vibrational absorption spectroscopy. This technique presents the advantages of high spectral selectivity, no calibration requirement, and high sensitivity. Two experimental setups were developed to measure NO densities and temperature, (1) within a NRP discharge in air, with 300-µm spatial resolution, and (2) downstream of NRP discharges in air and in plasma-assisted methane/air flames, using multi pass cell. [...]
Salhi, Abdelmajid. "Elaboration par EJM de diodes laser à base de GaSb pour des applications de puissance et de spectroscopie dans le moyen infrarouge". Montpellier 2, 2004. http://www.theses.fr/2004MON20073.
Testo completoPERMOGOROV, DMITRI. "Spectroscopie intracavite laser des transitions harmoniques du methane, silane, germane et de leurs derives deuteres dans les domaines visible et proche infrarouge". Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10074.
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