Methane monitoring by near infrared photoacoustic spectroscopy: The importance of relaxation phenomena

Chattez avec Graph Search

Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.

AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.

Applications such as optical clocks, gas spectroscopy, and optical coherent tomography stand to benefit significantly from the integration of on-chip supercontinuum sources. Materials exhibiting both second- and third-order nonlinearities are particularly ...

We present a numerically exact approach for evaluating vibrationally resolved electronic spectra at finite temperatures using the coherence thermofield dynamics. In this method, which avoids implementing an algorithm for solving the von Neumann equation fo ...

Atmospheric pressure low power plasma jets operating in noble gases are a widespread tool in plasma medicine studies. We present experimental results obtained in one such device, which combine physical, chemical and biological measurements to assess the ef ...

Solving native structures of such large molecules, like biomolecules, is often challenging, particularly due to the potentially infinite number of non-covalent interactions with water. In this thesis, we report the use of cold ion gas-phase action spectros ...

Infrared spectroscopy provides unique information on the composition and dynamics of biochemical systems by resolving the characteristic absorption fingerprints of their constituent molecules. Based on this inherent chemical specificity and the capability ...

Current agricultural practices are not sustainable; however, the non-thermal plasma treatment of seeds may be an eco-friendly alternative to alter macroscopic plant growth parameters. Despite numerous successful results of plasma-seed treatments reported i ...

We demonstrate novel approach for generation of optical combs in frequency shifting loop based on acousto-optic interaction. This approach provides comb multiplication with different line spacing and generation of dual-comb for spectroscopy applications. ( ...

WC-Co cemented carbides are composites, which combine a hard phase consisting of WC grains and a metallic ductile phase as a binder. Their excellent mechanical properties, combining high hardness, toughness and refractory properties, make them excellent ma ...

X-ray absorption linear dichroism of rutile TiO2 at the Ti K-edge provides information about the electronic states involved in the pre-edge transitions. Here, linear dichroism with high energy resolution is analyzed in combination with ab initio finite dif ...

One of the most prominent consequences of the quantum nature of light atomic nuclei is that their kinetic energy does not follow a Maxwell-Boltzmann distribution. Deep inelastic neutron scattering (DINS) experiments can measure this effect. Thus, the nucle ...

Understanding the relation between the gas-phase structure of biological molecules and their solution-phase structure is important when attempting to use gas-phase techniques to address biologically relevant questions. Directly after electrospray ionizatio ...

We present evidence that following near-UV excitation, protonated tyrosine- or phenylalanine–containing peptides undergo intersystem crossing to produce a triplet species. This pathway competes with direct dissociation from the excited electronic state and ...

The present study measures the sticking probability of heavy water (D2O) on H2O- and on D2O-ice and probes the inﬂuence of selective OD-stretch excitation on D2O sticking on these ices. Molecular beam techniques are combined with infrared laser excitation ...

What are the frequency, shape, kinematics, and luminosity of Ly alpha envelopes surrounding radio-quiet quasars at high redshift, and is the luminosity of these envelopes related to that of the quasar or not? As a first step towards answering these questio ...

We present the first detection of CO emission lines in the Ha filaments at distances as far as 50 kpc from the centre of the galaxy NGC 1275. This gas is probably dense (>= 10(3) cm(-3)). However, it is not possible to accurately determine the density and ...

Polycrystalline zirconia (3Y-TZP grade) specimens unreinforced and reinforced with multiwalled carbon nanotubes (MWCNTs) or silicon carbide whiskers (SiCws) were processed by powder metallurgy and studied by mechanical spectroscopy. The high-temperature me ...

Photoacoustic spectroscopy is a well-established gas traces optical detection technique, which consists in the generation of an acoustic wave in the investigated gas compound excited by a modulated laser beam, and in the detection of this sound wave with a ...

Absorption spectra of silane in the region of the first overtone of the Si-H stretch vibration have been recorded in a seeded supersonic jet expansion by cavity ring-down spectroscopy as well as in a static gas cell at room temperature by photoacoustic spe ...

Sub-ppm (HCl) and (H2O) monitoring using photoacoustic spectroscopy is reported in optical fibre manufacturing for the production of low-water-peak fibres. Contamination sources of the carrier gas used for fibre preforms manufacturing were identified and d ...

Photoacoustic spectroscopy is a widely recognised technique to measure trace gases at parts-per-million (ppm) or parts-per-billion (ppb) level using semiconductor laser in the near infrared range. This technique is based on the generation of an acoustic wa ...

Methane monitoring by near infrared photoacoustic spectroscopy: The importance of relaxation phenomena

Chattez avec Graph Search

Multi-octave bandwidth supercontinuum generation in crystalline Aluminum Nitride-on-sapphire waveguides

Finite-temperature vibronic spectra from the split-operator coherence thermofield dynamics

Combined Characterization of a Plasma Jet: FTIR, Chemical Surveys and Antibacterial Effect

Bridging Native and Intrinsic Structures of Microhydrated Biomolecules by Cold Ion Spectroscopy

Metasurface-Enhanced Infrared Spectroscopy: An Abundance of Materials and Functionalities

An In Situ FTIR Study of DBD Plasma Parameters for Accelerated Germination of Arabidopsis thaliana Seeds

Experimental Investigation of Tunable Acousto-Optic Frequency Combs

Optimization of composition and structure of cemented carbide cutting tools

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO2 single crystal

Nuclear Quantum Effects in Water at the Triple Point: Using Theory as a Link Between Experiments

Spectroscopic studies of kinetically trapped conformations in the gas phase: the case of triply protonated bradykinin

Fragmentation mechanism of UV-excited peptides in the gas phase

The sticking probability of D2O-water on ice: Isotope effects and the inﬂuence of vibrational excitation

Spectroscopy of extended Ly alpha envelopes around z=4.5 quasars

A very extended molecular web around NGC 1275

High-temperature mechanical loss and creep behavior of fine-grained zirconia-containing nano-sized reinforcements

Gas traces measurement by photoacoustic spectroscopy using Helmholtz resonator-based sensors

Cavity ring-down spectroscopy of jet-cooled silane isotopologues in the Si-H stretch overtone region

Optical Sensor for the Detection of OH- Contamination during Optical Fibre Manufacturing

Photoacoustic spectroscopy for multi-gas sensing using near infrared lasers