Relevant bibliographies by topics / THz simultaneous spectroscopy

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  2. Dissertations / Theses
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Academic literature on the topic 'THz simultaneous spectroscopy'

Author: Grafiati
Published: 25 May 2024

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Journal articles on the topic "THz simultaneous spectroscopy"

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Yamaguchi, Masashi, Minfeng Wang, and Pablo Suarez. "TERAHERTZ PHONON-POLARITON IMAGING FOR THE APPLICATION OF CHEMICAL DETECTION." International Journal of High Speed Electronics and Systems 17, no. 02 (June 2007): 355–65. http://dx.doi.org/10.1142/s0129156407004552.

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A combination of Terahertz (THz) polariton spectroscopy and polariton imaging technique for the application to chemical sensing is presented. We use phonon-polaritons, a coupled oscillation of the lattice vibration and radiation field, as an intense radiation source for THz spectroscopy. The propagation process of the polaritons generated in one of the two LiNbO 3 transducer crystals through the sample sandwiched between the crystals is visualized using a polariton imaging technique. Partially reflected polaritons at the transducer-sample interface and polaritons partially transmitted through the sample are visualized simultaneously in a single frame of an image. The temporal profile of reflected and transmitted phonon-polaritons can be obtained without scanning the delay time between the pump and probe femtosecond laser pulses unlike THz time-domain spectroscopy which requires point-by-point acquisition of the temporal pulse profile using conventional pump-probe scheme. The results suggest possible application of this technique to the chemical sensing with fast acquisition rate. The technique has been successfully applied to the measurement of liquid and solid samples, and simultaneous measurement of multiple samples has also been achieved.
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Oishi, Shingo, Yasuto Hijikata, Hiroyuki Yaguchi, and Sadafumi Yoshida. "Simultaneous Determination of the Carrier Concentration, Mobility and Thickness of SiC Homo-Epilayers Using Terahertz Reflectance Spectroscopy." Materials Science Forum 556-557 (September 2007): 423–26. http://dx.doi.org/10.4028/www.scientific.net/msf.556-557.423.

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We have simultaneously determined the carrier concentration, mobility, and thickness of 4H-SiC homo-epilayers with carrier concentration of 1016–1018 cm-3 from reflectance spectroscopy in the wavenumber range of 20–2000 cm-1. The spectra at 20–100 cm-1 and at 80–2000 cm-1 were measured by using the terahertz time domain spectrometer (THz-TDS) and the Fourier-transform infrared (FTIR) spectrometer, respectively. A modified classical dielectric function (MDF) model was employed for the curve fitting. We have compared the values of free carrier concentrations estimated from the reflectance spectroscopy with the net doping concentrations obtained from C–V measurements, and have discussed the validity of the electrical properties estimated from the reflectance spectroscopy.
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Denisov, Grigory, Irina Zotova, Ilya Zheleznov, Andrey Malkin, Alexander Sergeev, Roman Rozental, and Mikhail Glyavin. "Towards Watt-Level THz Sources for High-Resolution Spectroscopy Based on 5th-Harmonic Multiplication in Gyrotrons." Applied Sciences 12, no. 22 (November 9, 2022): 11370. http://dx.doi.org/10.3390/app122211370.

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We propose the concept of high-power THz radiation sources based on five-fold frequency multiplication in gyrotrons intended for plasma applications. The efficient excitation at the 5th cyclotron harmonic is due to the specific property of the eigenmodes of cylindrical waveguides, as a result of which, the conditions of simultaneous electrodynamic resonance at two selected TE modes are satisfied asymptotically with very high accuracy. Previously, we have verified this principle in experiments with a low-frequency kilowatt-level gyrotron in which, due to the low-density spectrum, the operating mode is excited with no competition from parasitic oscillations. The novel concept is a development of this idea applied to the systems with a denser spectrum, which is inevitable in higher frequency and power devices. Simulations within the averaged time-domain model demonstrate that, despite the mode competition, it is possible to excite Watt-level 1.25 THz 5th cyclotron harmonic in a recently developed sub-MW 0.25 THz gyrotron with TE19,8 operating mode. The obtained results open a possibility for implementation of radiation sources with output power/frequency combination, practically inaccessible using other THz generation methods and highly sought for a number of applications, including high-resolution molecular spectroscopy.
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Ferrante, Carino, Leonardo Lucchesi, Alessia Cemmi, Ilaria Di Sarcina, Jessica Scifo, Adriano Verna, Andrea Taschin, et al. "Gamma Irradiation Effect on Polymeric Chains of Epoxy Adhesive." Polymers 16, no. 9 (April 25, 2024): 1202. http://dx.doi.org/10.3390/polym16091202.

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The study of materials for space exploration is one of the most interesting targets of international space agencies. An essential tool for realizing light junctions is epoxy adhesive (EA), which provides an elastic and robust material with a complex mesh of polymeric chains and crosslinks. In this work, a study of the structural and chemical modification of a commercial two-part flexible EA (3M™ Scotch-Weld™ EC-2216 B/A Gray), induced by 60Co gamma radiation, is presented. Combining different spectroscopic techniques, such as the spectroscopic Fourier transform infrared spectroscopy (FTIR), the THz time-domain spectroscopy (TDS), and the electron paramagnetic resonance (EPR), a characterization of the EA response in different regions of the electromagnetic spectrum is performed, providing valuable information about the structural and chemical properties of the polymers before and after irradiation. A simultaneous dissociation of polymeric chain and crosslinking formation is observed.The polymer is not subject to structural modification at an absorbed dose of 10 kGy, in which only transient free radicals are observed. Differently, between 100 and 500 kGy, a gradual chemical degradation of the samples is observed together with a broad and long-living EPR signal appearance. This study also provides a microscopic characterization of the material useful for the mechanism evaluation of system degradation.
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Huang, Hsin-hui, Takeshi Nagashima, Tetsu Yonezawa, Yasutaka Matsuo, Soon Hock Ng, Saulius Juodkazis, and Koji Hatanaka. "Giant Enhancement of THz Wave Emission under Double-Pulse Excitation of Thin Water Flow." Applied Sciences 10, no. 6 (March 17, 2020): 2031. http://dx.doi.org/10.3390/app10062031.

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Simultaneous measurements of THz wave and hard X-ray emission from thin and flat water flow when irradiated by double femtosecond laser pulses (800 nm, 35 fs/transform-limited, 0.5 kHz, delay times up to 15 ns) were carried out. THz wave measurements by time-domain spectroscopy and X-ray detection by Geiger counters were performed at the transmission and the reflection sides of the flow. THz wave emission spectra show their dynamic peak shifts toward the low frequency with the highest intensity enhancements more than 1.5 × 10 3 times in |E| 2 accumulated over the whole spectrum range of 0–3 THz at the delay time of 4.7 ns between the two pulses. On the other hand, X-ray intensity enhancements are limited to about 20 times at 0 ns under the same experimental conditions. The mechanisms for the spectral changes and the intensity enhancements in THz wave emission are discussed from the viewpoint of laser ablation on the water flow induced by the pre-pulse irradiation.
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Huang, Hsin-hui, Takeshi Nagashima, Wei-hung Hsu, Saulius Juodkazis, and Koji Hatanaka. "Dual THz Wave and X-ray Generation from a Water Film under Femtosecond Laser Excitation." Nanomaterials 8, no. 7 (July 13, 2018): 523. http://dx.doi.org/10.3390/nano8070523.

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Simultaneous emission of the THz wave and hard X-ray from thin water free-flow was induced by the irradiation of tightly-focused femtosecond laser pulses (35 fs, 800 nm, 500 Hz) in air. Intensity measurements of the THz wave and X-ray were carried out at the same time with time-domain spectroscopy (TDS) based on electro-optic sampling with a ZnTe(110) crystal and a Geiger counter, respectively. Intensity profiles of the THz wave and X-ray emission as a function of the solution flow position along the incident laser axis at the laser focus show that the profile width of the THz wave is broader than that of the X-ray. Furthermore, the profiles of the THz wave measured in reflection and transmission directions show different features and indicate that THz wave emission is, under single-pulse excitation, induced mainly in laser-induced plasma on the water flow surface. Under double-pulse excitation with a time separation of 4.6 ns, 5–10 times enhancements of THz wave emission were observed. Such dual light sources can be used to characterise materials, as well as to reveal the sequence of material modifications under intense laser pulses.
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Gokus, Tobias. "Nano-FTIR Correlation Nanoscopy for Organic and Inorganic Material Analysis." ECS Meeting Abstracts MA2022-01, no. 7 (July 7, 2022): 622. http://dx.doi.org/10.1149/ma2022-017622mtgabs.

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Significance: Correlation scanning probe techniques to complement nanoscale IR measurements for next generation sample characterization Scattering-type Scanning Near-field Optical Microscopy (s-SNOM) is a scanning probe approach to optical microscopy and spectroscopy, bypassing the ubiquitous diffraction limit of light to achieve a spatial resolution below 20 nanometers. s-SNOM employs the strong confinement of light at the apex of a sharp metallic atomic force microscopy (AFM) tip to create a nanoscale optical hot-spot. Analyzing the scattered light from the tip enables the extraction of the optical properties of the sample directly below the tip and yields nanoscale resolved images simultaneous to topography [1]. In addition, the technology has been advanced to enable Fourier-Transform Infrared Spectroscopy on the nanoscale (nano-FTIR) [2] using broadband radiation from the visible spectral range to THz frequencies. Recently, the combined analysis of complex nanoscale material systems by correlating near-field optical data with information obtained by other scanning probe microscopy (SPM)-based measurement methodologies has gained significant interest. For example, the material-characteristic nano-FTIR spectra of a phase-separated polystyrene/low-density polyethylene (PS/LDPE) polymer blend verifies sharp material interfaces by measuring a line profile across a ca. 1 μm sized LDPE island. Near-field reflection/absorption imaging at 1500cm-1 of the ca. 50nm thin film allows to selectively highlight the distribution of PS in the blend and simultaneously map the mechanical properties like adhesion of the different materials [3,4]. Further, we present results that correlate the near-field optical response of semiconducting samples like graphene (2D) or functional SRAM devices (3D) in different frequency ranges (mid-IR & THz) to Kelvin Probe Force Microscopy (KPFM) measurements. Thus, s-SNOM systems represent an ideal platform to gain novel insights into complex material systems by different near-field and AFM-based method. [1] F. Keilmann, R. Hillenbrand, Phil. Trans. R. Soc. Lond. A 362, 787 (2004). [2] F. Huth, et al., Nano Lett. 12, 3973 (2012). [3] B. Pollard, et al., Beilstein J. of Nanotechn. 7, 605 (2016). [4] I. Amenabar, et al., Nature Commun. 8, 14402 (2017).
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Lan, Yang, Benjamin J. Dringoli, David A. Valverde-Chávez, Carlito S. Ponseca, Mark Sutton, Yihui He, Mercouri G. Kanatzidis, and David G. Cooke. "Ultrafast correlated charge and lattice motion in a hybrid metal halide perovskite." Science Advances 5, no. 5 (May 2019): eaaw5558. http://dx.doi.org/10.1126/sciadv.aaw5558.

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Hybrid organic-inorganic halide perovskites have shown remarkable optoelectronic properties, exhibiting an impressive tolerance to defects believed to originate from correlated motion of charge carriers and the polar lattice forming large polarons. Few experimental techniques are capable of directly probing these correlations, requiring simultaneous sub–millielectron volt energy and femtosecond temporal resolution after absorption of a photon. Here, we use time-resolved multi-THz spectroscopy, sensitive to the internal excitations of the polaron, to temporally and energetically resolve the coherent coupling of charges to longitudinal optical phonons in single-crystal CH3NH3PbI3 (MAPI). We observe room temperature intraband quantum beats arising from the coherent displacement of charge from the coupled phonon cloud. Our measurements provide strong evidence for the existence of polarons in MAPI at room temperature, suggesting that electron/hole-phonon coupling is a defining aspect of the hybrid metal-halide perovskites contributing to the protection from scattering and enhanced carrier lifetimes that define their usefulness in devices.
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Viščor, Petr, and Martin Viščor. "Electrical Impedance Spectroscopy: “First Principles” analysis and simulations of electrical response in the classical range of frequencies below 1 THz and the resulting new role of Electrical Impedance Spectroscopy in electrical characterisation within Condensed Matter Physics." Pure and Applied Chemistry 91, no. 11 (November 26, 2019): 1837–56. http://dx.doi.org/10.1515/pac-2018-1107.

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Abstract In order to investigate the full potential of the Electrical Impedance Spectroscopy (EIS) when used to address various aspects of conductive and dielectric response within the field of Condensed Matter Physics and Electrochemistry, a new analysis of the electrical impedance experiments has been undertaken. Within the framework of quantum mechanical band structure and using the concept of electrochemical potential for each of the relevant energies, the problem of electrical response in condensed phase has been formulated, using augmented Maxwell equations of Classical Electrodynamics, as a boundary value problem of a set of coupled, non-linear parabolic equations in energy, space and time. The result of this numerical analysis is a principal possibility of a complete electrical characterisation of both monocrystals, glassy solids and liquids. The EIS has been put in this way on a new qualitative level and should be considered now as the most general electrical experimental characterisation tool available. In this article, a methodology of numerical simulations of electrical response in condensed matter systems at classical frequencies (from ~1 THz down to dc) is presented and the numerical simulation results are then discussed, using monocrystalline Silicon, chalcogenide glass ion conductor Agx(AsS2)1−x and simple aqueous chloride solution as experimental test cases. Some other unique results of the new EIS analysis will also be discussed. These include the possibility of a clear distinction between the contribution to the electrical response from bound and mobile electrical charges, the possibility of simultaneous and independent determination of the mobile electrical charges mobility and their density in one EIS experiment and incorporation of the interfacial regions of the system under test (SUT) as an essential part of the overall electrical response.
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Grychtol, P., N. Kohlstrunk, J. Buck, S. Thiess, V. Vardanyan, D. Doblas-Jimenez, J. Ohnesorge, et al. "The SXP instrument at the European XFEL." Journal of Physics: Conference Series 2380, no. 1 (December 1, 2022): 012043. http://dx.doi.org/10.1088/1742-6596/2380/1/012043.

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Abstract The successful implementation of the baseline instruments at the European XFEL has triggered a second phase of instrument developments aiming to extend the portfolio of available techniques. At the soft X-ray undulator (SASE 3), the Soft X-ray Port (SXP) instrument is currently under construction. Conceived as an open port, it focuses primarily on femtosecond time-resolved X-ray photoelectron spectroscopy (TR-XPES), which has proven to be a powerful tool to understand the properties of materials and the interaction between their internal degrees of freedom. The extension of this technique to the soft X-ray energy range is only possible at MHz free electron lasers (FELs) due to space-charge effects which limit the maximum photon flux per pulse on the sample. In this contribution, the SXP instrument at the European XFEL and the implementation of TR-XPES using a momentum microscope are presented. The photon energy range available at SASE 3, 0.25 keV to 3.5 keV, and the variable polarization will allow for the simultaneous characterization of the electronic, magnetic, chemical and structural properties of materials with femtosecond time resolution. To this end, a wide range of laser excitation wavelengths, ranging from the XUV to the THz region, will be available.
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Dissertations / Theses on the topic "THz simultaneous spectroscopy"

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Tchana, betnga Wilfried. "Développement d'instrumentation pour une spectroscopie simultanée THz et IR : application à l'équilibre de HONO." Electronic Thesis or Diss., Université Paris Cité, 2023. http://www.theses.fr/2023UNIP7134.

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La mesure des concentrations d'espèces traces, susceptibles d'avoir un impact notable sur la santé, le climat ou la stabilité de la couche d'ozone constitue un véritable défi. Les prochaines missions spatiales, prévues à haute sensibilité (FORUM et IASI-NG), apporteront un progrès seulement si les paramètres spectraux nécessaires sont disponibles. Pour certaines espèces réactives, telles que l'acide nitreux (HONO) et l'acide hypobromeux (HOBr), les données spectroscopiques sont incomplètes ou quasiment inexistantes. Le défi dans cette thèse consiste à obtenir des paramètres spectroscopiques quantitatifs pour ces espèces. Pour atteindre cet objectif, un dispositif instrumental novateur impliquant l'utilisation simultanée de deux instruments, une expérience IR/THz, a été construit : une cellule thermostatée (200-350K) conçue en matériaux inertes, verre et téflon, est combinée à un spectromètre THz dans la région 0.1-1.1 THz et un spectromètre à Transformée de Fourier (FTS) à haute résolution (HR) dans le domaine IR. Le spectromètre THz permet de sélectionner plusieurs raies purement rotationnelles de la molécule cible pour la détermination de la pression partielle et le FTS la mesure simultanée du spectre rovibrationnel dans une fenêtre atmosphérique IR utilisable pour la quantification de l'espèce d'intérêt. La stratégie s'appuie donc sur le fait que les intensités des raies de rotation pure dépendent uniquement du moment dipolaire moléculaire, qui est connu avec précision à partir de mesures existantes par effet Stark. Dans le cas de HONO qui n'existe au laboratoire que sous la forme d'un équilibre avec H2O, NO et NO2, la méconnaissance de la pression partielle dans le mélange gazeux entraîne de sérieuses difficultés pour effectuer des mesures quantitatives. De plus, HONO possède deux formes isomériques et la hauteur de la barrière d'isomérisation entre le cis- et le trans-HONO DeltaCis-Trans est encore mal connue, ce qui affecte les positions et surtout les intensités de raies. Pour obtenir une valeur plus précise de cette barrière, des spectres ont été enregistrés à HR dans la gamme 50 - 200 cm-1, à 3 températures (240, 270 et 296 K), en utilisant le rayonnement synchrotron de la ligne AILES à SOLEIL. Des modélisations précises ont été effectuées et ont permis de déterminer la hauteur de la barrière DeltaCis-Trans = 95.8 ± 9.2 cm-1. Notre valeur est en bon accord avec la détermination précédente de Sironneau et al. (99 ± 25 cm-1) mais nous avons amélioré la précision d'un facteur 2.6. Nous avons utilisé cette nouvelle valeur de DeltaCis-Trans et les paramètres du moment dipolaire pour un calcul du spectre synthétique. Une liste de raies précise dans la région de l'IR lointain (0 - 200 cm-1) incluant les positions et intensités absolues a été compilée et s'est avérée plus robuste pour une meilleure détection de HONO dans les objets astrophysiques. Pour la détermination des intensités absolues dans la région IR moyen où HONO est actuellement détectée, des spectres simultanés IR/THz ont été enregistrés au LISA en utilisant l'instrumentation innovante développée durant cette thèse. Une première modélisation de ces spectres est présentée dans cette thèse et in fine, il en découlera une liste de raies pour HONO dans la région 730 - 920 cm-1 qui sera fourni à la communauté scientifique via les bases de données HITRAN et GEISA et exploitée dans l'analyse des observations satellitaires. Concernant HOBr, l'objectif sera de compiler une base de données spectroscopiques dans l'IR vers 8.6 um qui sera utilisée par IASI-NG et FORUM pour une détection et quantification dans l'atmosphère terrestre. Notons que HOBr joue un rôle important dans la chimie atmosphérique et n'existe au laboratoire que dans un mélange caractérisé par l'équilibre chimique : H2O + Br2O = 2(HOBr). La méthodologie et les outils expérimentaux développés durant cette thèse sont un atout pour la mise en oeuvre de ce projet qui, constitue les perspectives de ce travail
Measuring trace gases having a notable impact on human health, climate and the stability of the ozone layer constitutes an extremely important challenge. In the coming years, new, higher sensitivity satellite instruments will improve atmospheric sounding only if the necessary spectral parameters are available. For some species of atmospheric interest such as nitrous acid (HONO) and hypobromous acid (HOBr), spectroscopic data are incomplete or almost non-existent. The challenge in this thesis is to get quantitative spectroscopic parameters for these species. To achieve this objective, an innovative instrumental set-up involving the simultaneous use of two instruments, an IR/THz dual beam experiment, has been built: a thermostatically controlled cell (200-350K) made of inert materials, glass and Teflon, capable of accommodating a 0.1-1.1 THz spectrometer and coupled to a high resolution (HR) Fourier Transform spectrometer (FTS) in the IR range. The THz spectrometer allows to select rotational lines of the target molecule for partial pressure determination, and the FTS enables simultaneous measurement of the rovibrational spectrum in an IR atmospheric window for quantification of the species of interest. The adopted strategy relies on the fact that the intensities of the rotational spectra simply depend on the permanent dipole moment of the molecule of interest, determined with high accuracy from Stark effect measurements. In the case of HONO, which only exists in laboratory conditions in the form of an equilibrium mixture with other species like H2O, NO and NO2, the lack of knowledge of the partial pressure in the gas mixture leads to serious difficulties for quantitative measurements. In addition, HONO exists in two conformer forms, and the height of the conformer barrier between cis- and trans-HONO DeltaCis-Trans is still poorly known, which affects lines positions and especially lines intensities. To improve the determination of the energy difference between the ground vibrational state of the cis- and trans-HONO conformers of HONO, high resolution spectra were recorded in the 50-200 cm-1 spectral region at three different temperatures (240, 270 and 296 K), using the synchrotron radiation of the AILES beamline at SOLEIL. Precise modelling has been performed and were used to determine the height of the conformer barrier DeltaCis-Trans = 95.8 ± 9.2 cm-1. Our value is in good agreement with the previous determination by Sironneau et al (99 ± 25 cm-1), but we have improved the accuracy of this determination by a factor of 2.6. We used this new value of DeltaCis-Trans and the dipole moment parameters for a synthetic spectrum calculation. A precise line list in the far-IR region (0 - 200 cm-1), including positions and absolute lines intensities was generated and, proved to be more robust for an improved detection of HONO in astrophysical objects. To determine absolute intensities in the mid-IR region where HONO is currently detected, simultaneous IR/THz spectra were recorded at LISA using innovative instrumentation developed during this thesis. A first modelling of these spectra is presented in this thesis, and in fine will lead to a much more precise line list for HONO in the 730 - 920 cm-1 region, which will be provided to the scientific community via the HITRAN and GEISA databases and used in the analysis of satellite observations. Regarding HOBr, the aim will be to generate a spectroscopic database in the IR region around 8.6 um, to be used by IASI-NG and FORUM for detection and quantification in the Earth's atmosphere. HOBr plays an important role in atmospheric chemistry and, only exists in laboratory conditions in a mixture characterized by chemical equilibrium: H2O + Br2O = 2(HOBr). The methodology and experimental tools developed during this thesis will be an advantage for implementation of this project, which constitutes the outlook for this work
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Steedman, David John. "Simultaneous measurement of human brain activity using near infra-red spectroscopy, electroencephalogram and the steady state visually evoked potential." Swinburne Research Bank, 2008. http://hdl.handle.net/1959.3/48535.

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Thesis (M.Sc.) - Swinburne University of Technology, Brain Sciences Institute, 2008.
A thesis submitted for M.Sc by Research, Brain Sciences Institute, Swinburne University of Technology - 2008. Typescript. Includes bibliographical references (p. 117-153)
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Bacak, Michael. "Development of a detector for the simultaneous measurement and for the study of uranium-233 capture and fission yields at the CERN n_TOF neutron source." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS313/document.

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Des perspectives énergétiques sobres en carbone pour atténuer le changement climatique nécessitent le remplacement des combustibles fossiles par des sources produisant peu de CO2, par exemple l’énergie nucléaire. L'une des options discutées par le Forum international Gen-IV pour la prochaine génération de réacteurs nucléaires consiste à utiliser le cycle du thorium. L'isotope fissile 233U est l'un des isotopes les plus importants du cycle du thorium et est directement responsable du bilan neutronique. L'une des particularités de ce noyau est d'avoir une section efficace de capture qui est inférieure d'un ordre de grandeur à celle de fission. Cette circonstance rend très difficile la mesure de sa section efficace de capture, comme l'atteste seulement deux jeux de données à haute résolution disponibles depuis les années 1960. Dans cette thèse, une nouvelle mesure auprès de la source de neutrons n_TOF est décrite utilisant une nouvelle chambre à fission compacte insérée au centre d'un détecteur de rayons gamma, le calorimètre à absorption totale. La chambre à fission permet d’identifier et de soustraire les rayons gamma de la réaction de fission dans le but d’améliorer la précision de la section efficace de capture de 233U. La chambre à fission est conçue dans cet objectif. Son excellente performance est décrite en détail et permet d'extraire des informations sur les rayons gamma de fission. Une discussion détaillée du processus de réduction des données et des éléments clés de l’analyse, est présentée et aboutit au calcul du rapport alpha de 233U, le rapport entre la section efficace de capture et celle de fission
A low-carbon energy outlook to mitigate the climate change requires the replacement of fossil fuel by sources with low CO2 emissions, like nuclear energy.. One of the options discussed in the Gen-IV International Forum for the the next generation of nuclear reactors is to use the thorium cycle. The fissile isotope 233U is among the most important isotopes in the thorium cycle and directly responsible for the neutron economy. One of the particularities of this nucleus is to have a capture cross section which is one order of magnitude lower than fission, making the measurement of the 233U capture cross section very challenging as indicated by only two high resolution data sets available since the 1960s. In this thesis, a new measurement at the n_TOF neutron source is described employing a novel compact fission chamber inserted in the center of the Total Absorption Calorimeter g-ray detector. The fission chamber allows to tag and subsequently subtract the gamma rays from the fission reaction aiming to improve the accuracy of the 233U capture cross section.The performance of the custom tailored fission chamber is described in detail and allows to extract information about the prompt fission g-rays. A detailed discussion of the data reduction process and the key elements in the analysis is given resulting in the calculation of the 233U-alpha-ratio, the ratio between the capture and fission cross-section
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Le, Van-Hoan. "Analyses de microvolumes de gaz par spectroscopie Raman : expériences quantitatives et modélisation des mélanges CO₂-CH₄-N₂." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0178.

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Les inclusions fluides naturelles peuvent fournir des informations quantitatives précieuses pour reconstruire les conditions de circulation des paléofluides. CO₂, CH₄ et N₂ sont les espèces gazeuses majoritaires le plus souvent rencontrées dans divers environnements géologiques. Cependant les données d’étalonnage des mélanges constitués de ces espèces pour une quantification de leurs propriétés PVX ne sont pas encore complètement établies. L'utilisation des données de calibration disponible dans la littérature peut donc entraîner des erreurs significatives. L'objectif central de ce travail de thèse est d’apporter des données d’étalonnage du signal Raman des gaz CO₂, CH₄, N₂ et de leurs mélanges, sur une gamme de pression de 5 à 600 bars, afin de pouvoir déterminer simultanément les propriétés PVX à une température fixée. Pour cela, des mélanges de gaz ont été préparés à haute pression par le biais d'un mélangeur (GasMix AlyTech) couplé avec un système de pressurisation développé au laboratoire GeoRessources. Des analyses in situ Raman des mélanges de gaz ont été réalisées dans des conditions contrôlées en utilisant le système HPOC couplé avec un microcapillaire transparent placé sur une platine microthermométrique (Linkam CAP500). L’incertitude des mesures des propriétés PVX à 22 ou 32 °C à partir de nos équations d’étalonnage est de < 1 mol%, ~ ± 20 bars et ~ ± 0,02 g.cm-³ pour la composition, la pression et la densité, respectivement. Un autre objectif du projet est d'interpréter la tendance de variation de la position du pic du N₂ et/ou CH₄ pour une compréhension approfondie. Deux modèles théoriques, i.e., le potentiel de Lennard-Jones 6-12 et le modèle « Perturbed hard-sphere fluid » ont été utilisés pour évaluer quantitativement la contribution des forces d'interaction intermoléculaire attractives et répulsives aux décalages des bandes de CH₄ et N₂. Un modèle prédictif a été proposé pour prédire la tendance de la variation de la position du pic du CH₄ jusqu'à 3000 bars en fonction de la pression et de la composition. En fin, l'applicabilité de nos données d'étalonnage aux autres systèmes gazeux ou dans d’autres laboratoires est discutée et évaluée. Des nouvelles données d’étalonnage universelles applicables dans d’autres laboratoires sont fournies. Un programme de calcul « FRAnCIs » avec une interface utilisateur a été développé pour rendre l'utilisation de nos données d'étalonnage accessibles au plus grand nombre
Quantitative knowledge of species trapped within fluid inclusions provides key information to better understand geological processes as well as to reconstruct the conditions of paleofluid circulation. CO₂, CH₄, and N₂ are among the most dominant gas species omnipresent in various geological environments, but their quantitative PVX calibration data are not fully established yet. Using the previously published data can therefore lead to non-quantified errors, especially when applied to geological fluids containing generally several substances at elevated pressure and density. The aim of this work is to provide accurate calibration data for the simultaneous determination of PVX properties of pure gases or any binary and ternary mixtures of CO₂, CH₄, and N₂ over 5 to 600 bars at a fixed temperature, directly from Raman spectra. For this, gas mixtures were prepared and compressed using a mixer (GasMix AlyTech) coupled with a homemade pressurization system. Raman in situ analyses of gas mixtures were performed at controlled conditions using an improved HPOC system (High-Pressure Optical Cell) with a transparent microcapillary containing the prepared gas mixtures, placed on a heating-cooling stage (Linkam CAP500). Overall, the uncertainty of the measurement of the PVX properties of fluid inclusions from our calibration equations at 22 or 32 °C is < ± 1 mol%, ~ ± 20 bars, and ~ ± 0.02 g.cm-³ for molar proportion, pressure and density, respectively. The ensuing aim of the project is to interpret the variation trends of the peak position of the CH₄ and N₂ ν1 band for an in-depth understanding. Two theoretical models, i.e., Lennard-Jones 6-12 potential energy approximation and Perturbed hard-sphere fluid model were involved to quantitatively assess the contribution of the attractive and repulsive intermolecular interaction forces to the pressure-induced frequency shifts. A predictive model was also provided to predict the variation trend of the CH₄ ν1 band over a pressure range up to 3000 bars as a function of pressure and composition. Furthermore, the applicability of our calibration data to other laboratories and apparatus and to gas mixtures that contain a small amount of other species (e.g., H2, H2S) was discussed and evaluated. New universal calibration data applicable for other laboratories were then provided. A computer program “FRAnCIs” was also developed to make the application of our calibration data as convenient as possible via a user-friendly interface
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Larabi, Islam Amine. "Nouveaux produits de synthèse : analyse, consommation et métabolisme ; Applications cliniques et médicolégales Rapid and simultaneous screening of new psychoactive substances and conventional drugs of abuse. A comparative study of Biochip Array Technology versus LC-MS/MS in whole blood and urine Development of a sensitive untargeted liquid chromatography– high resolution mass spectrometry screening devoted to hair analysis through a shared MS2 spectra database: A step toward early detection of new psychoactive substances Validation of an UPLC-MS/MS method for the determination of sixteen synthetic cannabinoids in human hair. Application to document chronic use of JWH-122 following a non-fatal overdose Development and validation of liquid chromatography-tandem mass spectrometry targeted screening of 16 fentanyl analogs and U-47700 in hair: Application to 137 authentic samples Prevalence and Surveillance of Synthetic Cathinones Use by Hair Analysis: An Update Review Prevalence of New Psychoactive Substances(NPS) and conventional drugs of abuse (DOA) in high risk populations from Paris(France) and its suburbs A cross sectional study by hair testing(2012–2017) Evaluation of drug abuse by hair analysis and self-reported use among MSM under PrEP: Results from a sub-study of the ANRS-IPERGAY trial. Hair testing for 3‑fluorofentanyl, furanylfentanyl, methoxyacetylfentanyl, carfentanil, acetylfentanyl and fentanyl by LC–MS/MS after unintentional overdose Drug‐facilitated sexual assault (DFSA) involving 4‐methylethcathinone (4‐MEC),3,4‐Methylenedioxypyrovalerone (MDPV), and doxylamine highlighted by hair analysis Metabolic Profiling of Deschloro-N-ethyl-ketamine (O-PCE) and identification of new target metabolites in urine and hair using human liver microsomes and high-resolution accurate mass spectrometry." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASL029.

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L’objectif de ce travail a été de développer deux approches analytiques dédiées à l’analyse toxicologique des nouveaux produits de synthèse (NPS) dans différentes matrices biologiques (sang, urine et cheveux). La première est basée sur le criblage non ciblé par chimiluminescence sur biopuces et chromatographie liquide couplée à la spectrométrie de masse haute résolution (LC-HRMS) et la deuxième correspond à un criblage ciblé par spectrométrie de masse en tandem (LC-MS/MS). Ces deux approches ont ensuite été appliquées dans des études observationnelles pour évaluer la consommation de NPS dans des populations à risques de surdosage, de pharmacodépendance ou de soumission chimique dans un contexte clinique ou médico-judiciaire.La dernière partie a été consacrée au développement d’un nouvel outil analytique de traitement des données issues de la LC-HRMS qui a permis d’étudier le métabolisme de 9 NPS in vitro sur des cultures de microsomes du foie humain (HLM) et in vivo sur des échantillons biologiques d’usagers de ces drogues. Cette dernière approche a permis la création d’une bibliothèque de spectres de haute résolution composée de 228 métabolites dont certains ont été proposés comme marqueurs pertinents d’exposition aux NPS dont ils sont issus.Ce travail a été concrétisé par la rédaction de 10 publications scientifiques et a permis d’initier plusieurs collaborations pluridisciplinaires
The aim of the present work was to develop two analytical approaches dedicated to the analysis of new psychoactive substances in different biological matrices (blood, urine and hair). The first approach is based on untargeted screening by both biochip array technology chemiluminescence assay and liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) and the second corresponds to a targeted screening by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). These two approaches were then applied in observational studies to assess the consumption of NPS in high risk populations (overdose, drug abuse, drug facilitated crimes) in clinical and forensic settings. The last part of the work was devoted to the development of a new analytical tool for LC-HRMS data processing which made it possible to study the metabolism of 9 NPS In vitro on human liver microsomes (HLM) and In vivo in biological samples from drug users. This approach has enabled the creation of HRMS spectral library containing 228 metabolites, some of which have been proposed as relevant markers of NPS exposure.This work has resulted on 10 scientific publications and allowed to initiate many multidisciplinary collaborations
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Lin, Wei-Chen, and 林威呈. "A new approach for simultaneous characterization of the material's permittivity and permeability by THz time-domain spectroscopy." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/39400506040474816320.

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Hung, Yin Chem, and 程惠吟. "The Simultaneous Analysis of Aliphatic Chlorides in Air by Fourier Transform Infrared Spectroscopy." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/41013683993247258239.

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碩士
逢甲大學
化學工程研究所
83
Gas chromatographic (GC)technique was one of the most popular methods for the quantitative analysis of volatile or semi- volatile organic compounds. However, the pretreatments of concentrated sampling, the selection of columns, and the best separation conditions for the GC technique were tedious and complicated. Although the couple instruments of gas chromatography with mass spectrometer (GC/MS) were used successfully in both qualitative and quantitative analyses for the muticomponent sample. The usage of the GC/MS was not economical because of high costs and hard maintenance of mass spectrometer. Fourier Transform Infrared Spectroscopy(FTIR) with long path gas cell was an alternative technique for the analysis of gas samples. In this investigation, thirteen aliphatic chlorides : 1,2-Dichloroethane, 1,1,1-Trichloroethane, Tetrachloroethylene, Trichloroethylene, 1,2-Dichloropro-pane, 1,3-Dichloropropane , Carbon tetrachloride, Chloroform, Dichloromethane, 1,1-Dichloroethane, trans-1,2-Dichloroethylene, 1,1,2-Trichloroethane, 1,1,2,2-Tetrachloroethane were analyzed. The concentration of single component compound was obtained by FTIR technique down to 7 ppm. The multicomponent samples of ten aliphatic chlorides mixtures were also analyzed simultaneous from FTIR method. The results were calculated and compared with those from GC/FID technique. They were consistent within 12% 。
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Morais, Micael. "Application of simultaneous thermal analysis and mass spectroscopy on the characterization of lithium-sulfur batteries." Dissertação, 2013. http://hdl.handle.net/10216/74917.

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Morais, Micael Ângelo Preciso. "Application of simultaneous thermal analysis and mass spectroscopy on the characterization of lithium-sulfur batteries." Master's thesis, 2013. https://repositorio-aberto.up.pt/handle/10216/68813.

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Morais, Micael Ângelo Preciso. "Application of simultaneous thermal analysis and mass spectroscopy on the characterization of lithium-sulfur batteries." Dissertação, 2013. https://repositorio-aberto.up.pt/handle/10216/68813.

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Books on the topic "THz simultaneous spectroscopy"

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Geological Survey (U.S.), ed. The U.S. Geological Survey instrument for simultaneous multi-element atomic absorption spectrometry: Description of the hardware and of the system control and data aquisition software. [Reston, Va.?]: U.S. Dept. of the Interior, Geological Survey, 1987.

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Geological Survey (U.S.), ed. The U.S. Geological Survey instrument for simultaneous multi-element atomic absorption spectrometry: Description of the hardware and of the system control and data aquisition software. [Reston, Va.?]: U.S. Dept. of the Interior, Geological Survey, 1987.

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Geological Survey (U.S.), ed. The U.S. Geological Survey instrument for simultaneous multi-element atomic absorption spectrometry: Description of the hardware and of the system control and data acquisition software. [Reston, Va.?]: U.S. Dept. of the Interior, Geological Survey, 1987.

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Geological Survey (U.S.), ed. The U.S. Geological Survey instrument for simultaneous multi-element atomic absorption spectrometry: Description of the hardware and of the system control and data acquisition software. [Reston, Va.?]: U.S. Dept. of the Interior, Geological Survey, 1987.

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The U.S. Geological Survey instrument for simultaneous multi-element atomic absorption spectrometry: Description of the hardware and of the system control and data acquisition software. [Reston, Va.?]: U.S. Dept. of the Interior, Geological Survey, 1987.

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Book chapters on the topic "THz simultaneous spectroscopy"

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Mallik, Sushma V., N. S. Brickhouse, and A. K. Dupree. "Simultaneous X-ray and Optical Observations of the T Tauri star TW Hya." In Recent Advances in Spectroscopy, 193–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-10322-3_18.

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Dulin, David. "An Introduction to Magnetic Tweezers." In Single Molecule Analysis, 375–401. New York, NY: Springer US, 2023. http://dx.doi.org/10.1007/978-1-0716-3377-9_18.

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AbstractMagnetic tweezers are a single-molecule force and torque spectroscopy technique that enable the mechanical interrogation in vitro of biomolecules, such as nucleic acids and proteins. They use a magnetic field originating from either permanent magnets or electromagnets to attract a magnetic particle, thus stretching the tethering biomolecule. They nicely complement other force spectroscopy techniques such as optical tweezers and atomic force microscopy (AFM) as they operate as a very stable force clamp, enabling long-duration experiments over a very broad range of forces spanning from 10 fN to 1 nN, with 1–10 milliseconds time and sub-nanometer spatial resolution. Their simplicity, robustness, and versatility have made magnetic tweezers a key technique within the field of single-molecule biophysics, being broadly applied to study the mechanical properties of, e.g., nucleic acids, genome processing molecular motors, protein folding, and nucleoprotein filaments. Furthermore, magnetic tweezers allow for high-throughput single-molecule measurements by tracking hundreds of biomolecules simultaneously both in real-time and at high spatiotemporal resolution. Magnetic tweezers naturally combine with surface-based fluorescence spectroscopy techniques, such as total internal reflection fluorescence microscopy, enabling correlative fluorescence and force/torque spectroscopy on biomolecules. This chapter presents an introduction to magnetic tweezers including a description of the hardware, the theory behind force calibration, its spatiotemporal resolution, combining it with other techniques, and a (non-exhaustive) overview of biological applications.
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Nara, Issei, Toshiyuki Shiogai, Nahoko Tanaka, Manabu Tokitsu, and Isamu Saito. "Bilateral Simultaneous Monitoring of Regional Cerebrovascular Oxygen Saturation Using Near-Infrared Spectroscopy." In Neurochemical Monitoring in the Intensive Care Unit, 218–25. Tokyo: Springer Japan, 1995. http://dx.doi.org/10.1007/978-4-431-68522-7_27.

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Štefl, S., D. Baade, P. Harmanec, and L. A. Balona. "Simultaneous Photometry and Spectroscopy of the Rapid Variability of the Be Star η Cen." In Pulsation, Rotation and Mass Loss in Early-Type Stars, 307–8. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1030-3_83.

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Vittone, A., C. Rossi, E. Covino, and F. Giovannelli. "High S/N simultaneous optical and IR spectrophotometric observations of Herbig Ae/Be stars." In The Impact of Very High S/N Spectroscopy on Stellar Physics, 109–15. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2937-1_20.

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Seliverstov, M., A. Andreyev, N. Barré, H. De Witte, D. Fedorov, V. Fedoseyev, S. Franchoo, et al. "Study of the neutron deficient 182–190Pb isotopes by simultaneous atomic- and nuclear-spectroscopy." In LASER 2006, 225–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71113-1_23.

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Quack, Salina, and David Dulin. "Surface Functionalization, Nucleic Acid Tether Characterization, and Force Calibration for a Magnetic Tweezers Assay." In Single Molecule Analysis, 403–20. New York, NY: Springer US, 2023. http://dx.doi.org/10.1007/978-1-0716-3377-9_19.

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AbstractMagnetic tweezers are a force spectroscopy single-molecule technique. They enable the mechanical manipulation of biomolecules via the means of a magnetic particle under an attractive force applied by a magnetic field source. The magnetic particle is tethered to the glass surface of a flow chamber by the biomolecule, and functionalization strategies have been developed to reduce the nonspecific interactions of either the magnetic particles or biomolecules with the surface. Here, we describe two complementary strategies to achieve a high tether density while reducing the interactions of both the magnetic particle and the biomolecule of interest with the glass surface. Using a large detector CMOS camera, the simultaneous observation of several hundreds of tethered magnetic beads is achievable, allowing high-throughput single-molecule measurements. We further describe here a simple procedure to perform the calibration in force of a magnetic tweezers assay.
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Georg, Holger, Andreas Barth, Werner Kreutz, and Werner Mäntele. "Simultaneous Monitoring of Infrared Absorbance Changes and Related Changes in Intrinsic Fluorescence Due to Ca2+-Binding to Sarcoplasmic Reticulum (SR) Ca2+- ATPase." In Fifth International Conference on the Spectroscopy of Biological Molecules, 383–84. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1934-4_137.

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Oishi, Shingo, Yasuto Hijikata, Hiroyuki Yaguchi, and Sadafumi Yoshida. "Simultaneous Determination of the Carrier Concentration, Mobility and Thickness of SiC Homo-Epilayers Using Terahertz Reflectance Spectroscopy." In Materials Science Forum, 423–26. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-442-1.423.

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Farantatos, Panagiotis, Irene Karanasiou, and Nikolaos Uzunoglu. "An Integrated Approach towards Functional Brain Imaging Using Simultaneous Focused Microwave Radiometry, Near-Infrared Spectroscopy and Electroencephalography Measurements." In Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 351–57. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29734-2_48.

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Conference papers on the topic "THz simultaneous spectroscopy"

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Mieloszyk, Magdalena, Katarzyna Majewska, and Wieslaw Ostachowicz. "THz spectroscopy application for fibre reinforced polymer structures under influence of simultaneous temperature and humidity action." In Health Monitoring of Structural and Biological Systems XV, edited by Paul Fromme and Zhongqing Su. SPIE, 2021. http://dx.doi.org/10.1117/12.2581276.

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Nemec, H., P. Kuzel, F. Kadlec, L. Duvillaret, and J. L. Coutaz. "Simultaneous Determination of Dielectric Permittivity and Magnetic Permeability of Bulk Samples by THz Time-Domain Spectroscopy." In >2006 Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Teraherz Electronics. IEEE, 2006. http://dx.doi.org/10.1109/icimw.2006.368694.

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MAJEWSKA, KATARZYNA, MAGDALENA MIELOSZYK, and WIESLAW OSTACHOWICZ. "Fibre Reinforced Polymer Structure Under Simultaneous Temperature and Humidity Influence—FBG Sensors, THz Spectroscopy, and Vibrothermography Methods." In Structural Health Monitoring 2019. Lancaster, PA: DEStech Publications, Inc., 2019. http://dx.doi.org/10.12783/shm2019/32418.

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Madej, A. A., B. G. Whitford, K. J. Siemsen, and J. D. Sankey. "Absolute frequency measurement of a single-ion optical transition: the 24-THz excited-state transition in Ba+." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/oam.1993.tua.1.

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A single, laser cooled ion held in a radio-frequency trap is a near ideal system for high resolution spectroscopy and for new optical frequency standards. We report the first absolute frequency measurement of a single ion optical transition using a frequency chain referenced to a primary frequency standard. The D-D excited state, fine structure transition at 24 THz of a single, laser cooled ion was probed using an electro-optic shifted, frequency sideband from an optically pumped ammonia laser operating on the sP (8,6) line. By recording the ion quantum jump rate as a function of laser detuning, single ion lineshapes were obtained free of any Doppler broadening. Measurements of the ion motional temperature gave estimates below 15 mK and a time dilation shift below 2 × 1017. A phase-locked, optical frequency synthesis chain starting from a primary cesium standard to the 24.029 THz ammonia probe laser frequency has been constructed and can provide accuracies of 1013. Simultaneous measurement of the ammonia probe laser frequency and the shifted sideband frequency have enabled an absolute frequency determination with an uncertainty below the kilohertz level at the optical probe frequency of 24 THz limited by the current linewidth and stability of the ammonia probe laser.
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Kawada, Yoichi, Katsumasa Yoshioka, Yusuke Arashida, Ikufumi Katavama, Jun Takeda, and Hironori Takahashi. "Spectroscopic Measurement of Birefringent Materials by Simultaneous Acquisition of Two-Polarization-State THz Pulse Responses." In 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz 2018). IEEE, 2018. http://dx.doi.org/10.1109/irmmw-thz.2018.8510362.

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Vilimpoc, V., B. Sarka, W. L. Weaver, J. R. Gord, and S. Anderson. "Techniques to Characterize the Thermal-Oxidation Stability of Jet Fuels and the Effects of Additives." In ASME 1996 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-gt-044.

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Three techniques integrated into a single instrumented platform allow simultaneous measurement in real time of particle-size growth rate, surface mass-deposition rate, and concentration of dissolved oxygen in thermally stressed jet fuel. Particle growth rate is studied using Photon Correlation Spectroscopy (PCS); surface mass-deposition rate is measured with a Quartz Crystal Microbalance (QCM); and dissolved-oxygen concentration is monitored by Pyrene Fluorescence Quenching (PFQ). The three techniques have been used simultaneously to study the behavior of a jet fuel undergoing thermal stressing and to evaluate the performance of an anti-oxidant, a dispersant, and a metal deactivator in another jet fuel.
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Lieberman, R. A. "Fiber-optic sensors for environmental applications." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/oam.1993.thp.1.

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The use of optical fibers for chemical monitoring predates communications uses. In recent years, advances in fiber optic and semiconductor technology, as well as in analytical chemistry and biochemistry, have made fiber optic chemical sensors very attractive for a wide variety of environmental applications. Remote spectroscopic measurements via optical fibers (passive fiber optic chemical sensing), including fluorescence and Raman spectroscopy, and often multiplexing many fibers to provide simultaneous multipoint chemical information, have become well accepted in the process control and environmental monitoring industries. Active techniques, in which chemically sensitive devices, or “optrodes”, are attached to fibers, are being intensively studied, and a few sensor systems based on these are beginning to appear as commercial products. Intrinsic sensors, in which optical fibers are the actual chemical transduction devices, have begun to attract wide attention, because of their potential for continuous long-path monitoring. Chemical sensing requirements challenge fiber optic researchers: new optical fiber designs (D-fibers, hollow waveguides, multi-core, off-center core, tapered geometries, and others) are being investigated to enhance fiber chemical sensitivity. New fiber materials (fluorozirconate, chalcogenide, sapphire, silver halide, and others) are being developed to extend transmission into the infrared “chemical fingerprint” region of the electromagnetic spectrum.
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Kawasaki, Naoki, Bin Fan, Kei-ichi Namiki, Yunglin Chang, Takayuki Kobayashi, and Hyuga Taniguchi. "Accurate optical properties by simultaneous fitting of spectroscopic datasets of single- & multi-layers." In Optical Interference Coatings. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/oic.2022.tha.7.

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We have developed an analytical method to determine accurate optical properties by a simultaneous fitting of spectroscopic measurements of single- and multilayers. Here, TiN and TiN/SiN samples are subjected to an evaluation of the method.
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Jiao, Tengfei, Kin-Pang Cheong, Wenju Hu, and Liuhao Ma. "Simultaneous Measurements of Temperature, H2O concentration and Pressure by Multiline Laser Absorption Spectroscopy." In Applied Industrial Spectroscopy. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/ais.2023.jtu4a.9.

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Based on multiline laser absorption spectroscopy, numerical study is conducted to demonstrate the simultaneous measurements of temperature, H2O concentration and pressure by fully utilization of two segments of near infrared spectra.
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Cristescu, S. M., K. E. Jahromi, A. Khodabakhsh, V. Bosman, F. J. M. Harren, M. K. Dasa, E. Rokx, H. Martin, and M. Nematollahi. "Volatiles detection using broadband mid-IR spectroscopy: from a research idea to application in fruit storage facilities." In Applied Industrial Spectroscopy. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/ais.2023.atu5a.2.

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A broadband mid-infrared gas sensor using a supercontinuum light source is developed for simultaneous multispecies detection. We present the journey from a laboratory setup towards a market-ready prototype for application in fruit storage facilities.
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Reports on the topic "THz simultaneous spectroscopy"

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Agassi, Menahem, Michael J. Singer, Eyal Ben-Dor, Naftaly Goldshleger, Donald Rundquist, Dan Blumberg, and Yoram Benyamini. Developing Remote Sensing Based-Techniques for the Evaluation of Soil Infiltration Rate and Surface Roughness. United States Department of Agriculture, November 2001. http://dx.doi.org/10.32747/2001.7586479.bard.

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The objective of this one-year project was to show whether a significant correlation can be established between the decreasing infiltration rate of the soil, during simulated rainstorm, and a following increase in the reflectance of the crusting soil. The project was supposed to be conducted under laboratory conditions, using at least three types of soils from each country. The general goal of this work was to develop a method for measuring the soil infiltration rate in-situ, solely from the reflectance readings, using a spectrometer. Loss of rain and irrigation water from cultivated fields is a matter of great concern, especially in arid, semi-arid regions, e.g. much of Israel and vast area in US, where water is a limiting factor for crop production. A major reason for runoff of rain and overhead irrigation water is the structural crust that is generated over a bare soils surface during rainfall or overhead irrigation events and reduces its infiltration rate (IR), considerably. IR data is essential for predicting the amount of percolating rainwater and runoff. Available information on in situ infiltration rate and crust strength is necessary for the farmers to consider: when it is necessary to cultivate for breaking the soil crust, crust strength and seedlings emergence, precision farming, etc. To date, soil IR is measured in the laboratory and in small-scale field plots, using rainfall simulators. This method is tedious and consumes considerable resources. Therefore, an available, non-destructive-in situ methods for soil IR and soil crusting levels evaluations, are essential for the verification of infiltration and runoff models and the evaluation of the amount of available water in the soil. In this research, soil samples from the US and Israel were subjected to simulated rainstorms of increasing levels of cumulative energies, during which IR (crusting levels) were measured. The soils from the US were studied simultaneously in the US and in Israel in order to compare the effect of the methodology on the results. The soil surface reflectance was remotely measured, using laboratory and portable spectrometers in the VIS-NIR and SWIR spectral region (0.4-2.5mm). A correlation coefficient spectra in which the wavelength, consisting of the higher correlation, was selected to hold the highest linear correlation between the spectroscopy and the infiltration rate. There does not appear to be a single wavelength that will be best for all soils. The results with the six soils in both countries indeed showed that there is a significant correlation between the infiltration rate of crusted soils and their reflectance values. Regarding the wavelength with the highest correlation for each soil, it is likely that either a combined analysis with more then one wavelength or several "best" wavelengths will be found that will provide useful data on soil surface condition and infiltration rate. The product of this work will serve as a model for predicting infiltration rate and crusting levels solely from the reflectance readings. Developing the aforementioned methodologies will allow increased utilization of rain and irrigation water, reduced runoff, floods and soil erosion hazards, reduced seedlings emergence problems and increased plants stand and yields.
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