Materials are subject to alteration when exposed to an urban environment and are potentially sensitive to the evolution of environmental parameters (rapidly densifying urbanization and environmental changes). For this reason the sustainable building has lately become a hot topic and the preservation of ancient monuments, an environmental, economic, and cultural challenge. To predict the alteration rates of materials from the built heritage in an evolving environment (climate and pollution), a geochemical model based on physic-chemical processes and kinetics parameters must be developed. Thus, the GLAM project aims at modeling the alteration of two reference materials - stained glass and limestone - widely used in historical buildings exposed to an urban area. They have also been selected because they are different in terms of chemical composition and porosity so that the model could be extended to a large range of materials. To this purpose, we propose to set up dedicated laboratory experiments in realistic conditions of rainfall, condensation and unsaturated conditions. To evaluate the role of the alteration layer formation on the kinetics, materials at different alteration stages will be analyzed: pristine, laboratory weathered, and middle and long-term weathered in a real environment. Their alteration in laboratory will be combined with isotopic tracing of water transfer (D218O) and of secondary phase formation zones (18O, 29Si, 13C and 34S). This will enable to locate and quantify the reaction zones inside the materials in order to provide data on the alteration mechanisms and kinetics. Moreover a fine characterization of the environmental conditions (weathering solution, temperature, relative humidity, composition of the atmosphere) and of the materials (multiscale identification of the alteration pattern and of the pore/crack network) will provide a conceptual formalization of the mechanisms. All these data will be used as inputs in a numerical geochemical alteration model. Two approaches for the models will be developed in parallel and compared: a chemistry-geochemical transport coupled model, and a pore network model to assess the validity of simplifying hypotheses concerning the transport and to reinforce the robustness of the geochemical model. This interdisciplinary project gathers scientists from different communities (cultural heritage, environmental sciences, materials sciences, physics and geochemistry) in order to propose an innovative methodology aiming at understanding the alteration of built heritage materials and to develop alteration models to assess the impact of climate and pollution on their alteration. Thus the results of the GLAM project will be of major importance in the community of the environmental sciences as well as the one of the conservation. First it will help developing more accurate strategies for the preservation of the built cultural heritage. Second it will provide efficient tools to assess the impact of pollution on built heritage that is now a criterion in the reducing and prevention pollution policies (e.g. UNECE Convention on Large-Range Transboundary Air Pollution).

The objective of the B2C project is to spectrally resolve the optical properties of carbonaceous aerosols (black and brown carbon: BC, BrC) and their variability in link with the particle formation process and atmospheric aging in order to provide the required parameterizations to climate models and remote sensing retrievals so to constrain their global and regional radiative effect. The B2C project proposes an original mechanistic study in the controlled and well-characterized atmosphere of the large CESAM simulation chamber and takes advantages of its recent instrumental developments including the new UV-Vis spectrometer that allows measuring aerosol extinction spectra at high spectral resolution and at different relative humidity levels, as required by climate models and remote sensing. B2C builds up on the established expertise of the PI and the LISA team involved in the project to design original laboratory experiments to study the optical properties of 1/ Primary absorbing BC aerosols, taken as representative of freshly emitted combustion BC particles, 2/ Aged primary absorbing BC aerosols, so BC particles after they have undergone heterogeneous reaction with atmospheric constituents inducing the formation of inorganic/organic coatings on them, and 3/ Chemically-generated secondary absorbing BrC aerosols, so BrC particles formed by in situ atmospherically-relevant chemical processing of Secondary Organic Aerosols, including both non-aqueous and aqueous-phase processes. The strategy of the B2C project will consist at generating aerosols in CESAM and make them to age in realistic and atmospheric-relevant conditions, and at characterizing simultaneously their spectral optical properties and physico-chemical state based on state-of-the-art instrumentation, established laboratory protocols, and advanced modelling approaches. B2C will quantify the impact of chemical composition and morphology on the essential optical properties of these particles: the mass extinction, absorption, and diffusion efficiencies (MEC, MAC, MSC), the complex refractive index and the single scattering albedo (SSA). The B2C project will provide original and complementary data to previous studies so permitting the characterization of optical properties over the entire UV-Vis-IR spectrum. These data are required in models to constrain the direct radiative effect of BC and BrC on climate. The deliverable of the B2C project will be the spectrally-resolved CRI, MAC, MSC, MEC and SSA for BC and BrC aerosols in dry and wet conditions, for different aging states, and their relation to particle chemistry and morphology.

The influence of some greenhouses gases (carbon dioxide and methane) on the Earth climate is a major environmental, societal, and political issue. Numerous instruments (ground-based or satellite-borne) aim at monitoring these gases in the Earth atmosphere with very high accuracy. The analysis of the measured data, mostly done through the so-called "inversion" procedures, requires the knowledge of the intrinsic spectroscopic parameters of absorption lines (positions, intensities,...). However the collisions between the molecules also have to be considered as their effects yield a modification of the line shape for most of the atmospheric physical conditions (pressure, temperature). The collisionnal parameters describing these effects (half-widths, line shifts, and their temperature dependence, line-mixing parameters,...), and the line shape models are now recognized as being the main source of systematic errors for the remote determination of the greenhouse gases abundances through the inversion procedures. Most of these procedures use the Voigt line shape, convolution of the Gaussian and Lorentzian profiles, despite its well-known deficiencies which yield biases on the remotely sensed parameters. In order to take into account the deviations from the Voigt profile, numerous empirical (or semi-empirical) models, based on one (or more) ad-hoc parameters adjusted on available experimental data, were developed. Due to their empirical nature, these models do not have strong physical bases so that they can lead to miss-interpretations and erroneous predictions when used for extrapolations. This project aims to answer some of the questions raised by the deviations to the Voigt profile, needed for an accurate determination of the concentrations of the greenhouses gases. Hence, the proposed research should provide new physically-based models and associated software, involving no adjustable parameter when possible, that would be used in the remote sensing and radiative transfer codes. For that, the main tasks proposed here are : (1) the in-depth study of the currently available models; (2) the development of new theoretical approaches and subsequent software; (3) the laboratory measurements; and (4) the study of the atmospheric spectra with the new approaches, and their consequences on the determination of molecular abundances. The methodology proposed for the resolution of these tasks is recent but some have been validated on CO2 by some studies. The hopes are that these new approaches, robust and validated using laboratory measurements and atmospheric spectra, will reduce the uncertainty on the abundances of CO2 and CH4, thus contributing to the success of the actual and future satellite missions devoted to the quantitative cartography of the sinks and sources of these greenhouse gases.

The SFERE project aims to improve the characterisation of extraterrestrial organic matter thanks to the development of supercritical fluid extraction (SFE) of extraterrestrial samples. These samples are precious and generally poor in organic matter. Also, this organic matter is usually strongly linked to the mineral matrices, therefore the extraction must be adapted. The SFE should limit the contamination and chemical evolution risks while increasing the recovery yield of the molecules of prebiotic interest: amino acids, carboxylic acid, sugars, etc. However, the extraction step is challenging and must be optimised. Some meteorites available on Earth will be the first objects to be studied followed by Mars analogues. To develop the extraction by SFE for each category of extraterrestrial object, it is necessary to optimise the various parameters of SFE (temperature, pressure, co-solvents, time of extraction…). The sample characterisation will be carried out by chromatography coupled to mass spectrometry (MS) and more particularly we wish to use on-line supercritical fluid chromatography (SFC) that will improve the separation of the molecules, thus their identification by MS. The optimised parameters will be validated by comparison against other extraction techniques (Soxhlet, ultrasons and ASE) . The results will help the comprehension of organic matter complexification and prebiotic chemistry. This study comes within the scope of the sample return space missions that have developed strongly those past few years. On the long term, the development of a spatial instrument and its implementation on space missions could be contemplated in order to improve the in-situ characterisation.

The objective of the project is to develop a microwave spectrometer capable of high-sensitivity and high-resolution pure rotational spectroscopy for spectral analysis, structure determination, and for three-wave mixing experiments for chiral analysis. This novel apparatus called PARIS-FTMW combines a pulsed jet (narrow-band) resonator-type and a (broadband) chirped-pulse Fourier transform microwave spectrometer. Using a smart design, most electronic components will be used in a dual-purpose setup while all vacuum parts are identical. The two types of spectrometers are operated in either mode at no turn-around time. This highly integrated, innovative machine built at much lower costs yet offers the advantages of both techniques: Rapid broadband capabilities and unchallenged resolving power. Enantiomer-specific detection by multiple resonance experiments is feasible with the spectrometer design. This instrument uses high frequency microwave pulses and applies this pulses in an optimal, time-separated pulse sequence, employing efficiently the nature of close-lying b- and c-type rotational transitions of a chiral molecule with the 1 GHz band-width of the chirped pulse in use. Chiral discrimination is currently not a standard method in microwave spectroscopy. PARIS-FTMW with its flexibility in configuration changes will turn high resolution microwave spectroscopy into a powerful method for a routine application of chiral detections. Studies on bio-active chiral molecules like odorant terpenes, pheromones, and complexes will be performed with chiral discrimination applications, yielding precise parameters of the molecular systems and the handedness of the molecules. This clearly integrates multidisciplinary aspects, especially for astronomy, Earth's atmosphere, and biology. The three molecular systems chosen are linalool, linalyl acetate, and the 1,2-propanediol--propylene oxide complex. All molecules are chiral and thus highlight the capability of PARIS-FTMW for chiral discrimination. Furthermore, they are flexible and floppy, therefore feature complex large amplitude motions which serve as tests for theoretical models and developments.