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Paul-Émile (François) Lecoq de Boisbaudran (1838-1912) was an important French chemist in the second half of the XIX century and the first decade of the XX century. He was one of the founders of spectroscopy. He discovered gallium (1875), samarium (1879), and dysprosium (1886) and improved methods for the separation of rare earths elements. The purpose of this paper is to familiarize readers with the important events in the life of Lecoq de Boisbaudran and his great discoveries. In addition, literature on his selected papers and books, as well as literature on his chapters in books is presented. [ABSTRACT FROM AUTHOR]

Several generations of chamosite, including a red variety, occur in the Ordovician hydrothermalized oolitic ironstone from Saint-Aubindes-Châteaux (Armorican Massif, France). Their chemical re-examination indicates a low Mg content (0.925 < Fe/(Fe + Mg) < 0.954), but a significant variation in IVAl. Minor vanadium is present at up to 1.1 wt.% oxide. Variations in IVAl, the vanadium content and the colour of chamosite are related to the hydrothermal reworking of the ironstone. Taking into account other published data, the ideal composition of chamosite is (Fe5-xAl1+x)(Si3-xAl1+x)O10(OH)8, with 0.2 < x < 0.8 (0.2: equilibrium with quartz; 0.8: SiO2 deficit). The red chamosite (IIb polytype) has a mean composition of (Fe3.87Mg0.23Mn0.01X0.07Al1.74V0.07)(Si2.33Al1.67)O10(OH)8. This chamosite is strongly pleochroic, from pale yellow (E || (001)) to deep orange red (E = (001)). Visible-near-infrared absorbance spectra show a specific absorption band centred at ~550 nm for E = (001), due to a proposed new variety of Fe/V intervalence charge-transfer mechanism in the octahedral sheet, possibly Fe2+ - V4+ = Fe3+ - V3+. While the formation of green chamosite varieties is controlled by reducing conditions due to the presence of organic matter as a buffer, that of red chamosite would indicate locally a weak increase of fO2 related to oxidizing hydrothermal solutions. [ABSTRACT FROM AUTHOR]

Raman spectroscopy and X-ray fluorescence spectrometry are powerful analytical techniques that allow for molecular and elemental analysis, respectively. Recent developments allowed for the miniaturization of equipment to an extent that in-situ experiments become available. There are many advantages in using portable instruments, but this requires sacrifices regarding the acquisition of the spectra and the quality of the analysis. How much information is lost with this exchange is not clear, neither how important this is for the use of these techniques as forensic tools. In this work, the damage of a façade of Villa Belza, a historic building in Biarritz, France, was evaluated using both portable and benchtop versions of X-ray fluorescence (XRF) and Raman spectroscopy and the approaches were compared. As the comparison of instruments designed for different conditions is not straightforward, the authors use a number of settings to discuss what would be a realistic juxtaposition of results and how this affects the diagnosis of the structure. Furthermore, some hand-held XRF spectrometers are not connected to appropriate software to proceed with the data treatment and the processing of such signals can be tedious or too time consuming. Thus this work also proposes an algorithm for the automatic identification and comparison of elements in the XRF spectra acquired on site. After discussing the trade-off involved with each technique and the respective effect in the limit of detection, the authors conclude that the extra information from benchtop instruments was negligible for this case study. • Comparison between accuracy of hand-held and benchtop Raman and XRF spectrometry • Creation of freely available MATLAB script for analysis of XRF spectra from hand-held device • In-situ spectroscopy suffices to find salt weathering agents in historic building in marine environment • Laboratory spectroscopy provides additional information of second order on degradation phenomena. [ABSTRACT FROM AUTHOR]

We investigate the statistical properties of votes of customers for spots of France collected by the startup company Nomao. The frequencies of votes per spot and per customer are characterized by a power law distribution which remains stable on a time scale of a decade when the number of votes is varied by almost two orders of magnitude. Using the computer science methods we explore the spectrum and the eigenvalues of a matrix containing user ratings to geolocalized items. Eigenvalues nicely map to large towns and regions but show certain level of instability as we modify the interpretation of the underlying matrix. We evaluate imputation strategies that provide improved prediction performance by reaching geographically smooth eigenvectors. We point on possible links between distribution of votes and the phenomenon of self-organized criticality. [ABSTRACT FROM AUTHOR]

As new experimental data arrive from the LHC the prospect of indirectly detecting new physics through precision tests of the Standard Model grows more exciting. Precise experimental and theoretical inputs are required to test the unitarity of the CKM matrix and to search for new physics effects in rare decays. Lattice QCD calculations of non-perturbative inputs have reached a precision at the level of a few percent; in many cases aided by the use of lattice perturbation theory. This review examines the role of lattice perturbation theory in B physics calculations on the lattice in the context of two questions: how is lattice perturbation theory used in the different heavy quark formalisms implemented by the major lattice collaborations? And what role does lattice perturbation theory play in determinations of non-perturbative contributions to the physical processes at the heart of the search for new physics? Framing and addressing these questions reveals that lattice perturbation theory is a tool with a spectrum of applications in lattice B physics. [ABSTRACT FROM AUTHOR]

Abstract: We provide a complete extension of Minimal Walking Technicolor able to account for the Standard Model fermion masses. The model is supersymmetric at energies greater or equal to the technicolor compositeness scale. We integrate out, at the supersymmetry breaking scale, the elementary Higgses. We use the resulting four-fermion operators to derive the low energy effective theory. We then determine the associated tree-level vacuum and low energy spectrum properties. Furthermore we investigate the phenomenological viability of the model by comparing its predictions with electroweak precision tests and experimental bounds on the mass spectrum. We then turn to the composite Higgs phenomenology at the LHC and show that current data are already constraining the parameter space of the model. [Copyright &y& Elsevier]

Abstract: We celebrate the recent Higgs discovery announcement with our experimental colleagues at the LHC and look forward to the implications that this success will bring to bear upon the continuing search for supersymmetry (SUSY). The model framework named No-Scale – possesses the rather unique capacity to provide a light CP-even Higgs boson mass in the favored 124–126 GeV window while simultaneously retaining a testably light SUSY spectrum that is consistent with emerging low-statistics excesses beyond the Standard Model expectation in the ATLAS and CMS multijet data. In this Letter we review the distinctive – mechanism that forges the physical 125 GeV Higgs boson and make a specific assessment of the ATLAS multijet SUSY search observables that may be expected for a 15 fb−1 delivery of 8 TeV data in this model context. Based on our Monte Carlo study, we anticipate that the enticing hints of a SUSY signal observed in the 7 TeV data could be amplified in the 8 TeV results. Moreover, if the existing signal is indeed legitimate, we project that the rendered gains in significance will be sufficient to conclusively rule out an alternative attribution to statistical fluctuation at that juncture. [Copyright &y& Elsevier]

Phenomenological Tsallis fits to the CMS and ATLAS transverse spectra of charged particles were found to extend for pT from 0.5 to 181 GeV in pp collisions at the LHC at √s = 7 TeV, and for pT from 0.5 to 31 GeV at √s = 0:9 TeV. The simplicity of the Tsallis parametrization and the large range of the fitting transverse momentum raise questions on the physical meaning of the degrees of freedom that enter into the Tsallis distribution or q-statistics. [ABSTRACT FROM AUTHOR]

The ability of near-infrared spectroscopy to trace cow feeding systems and farming altitude was tested on 486 bulk milk samples from France and northwestern Italy. Milks were grouped into feeding systems according to the main forage in the diet. Partial least square discriminant analysis correctly classified 95.5, 91.5, and 93.3% of pasture versus maize silage, hay, and fermented herbage feeding systems, respectively. Discrimination was slightly less successful when diets with large proportions of the nondominant forage were included in each group. Near-infrared spectroscopy correctly discriminated no-pasture from pasture milk, even with only 30% of pasture in the diet (5.4% crossvalidation error), and the error stabilized when pasture exceeded 70% (2.5% error). Near-infrared spectroscopy did not reliably trace milk geographic origin when the feeding system effect was isolated from the altitude effect. These findings may be usefully exploited for the authentication of dairy products. [ABSTRACT FROM AUTHOR]

Hadron physics represents the study of strongly interacting matter in all its manifestations and understanding its properties and interactions. The interest in this field has been revitalized by the discovery of new light hadrons, charmonium- and bottomonium-like states. In this paper, the most recent experimental results from different experiments are reviewed. [ABSTRACT FROM AUTHOR]

Abstract: We present the production cross-section of γ-rays based on data of p–p collisions at the Large Hadron Collider (LHC), revising the previous semi-empirical formula mainly for (1) the inelastic cross-section in p–p collisions, , and 2) the inclusive γ-ray spectrum in the forward region, . We find that the previous cross-section gives a significantly softer spectrum than found in the data of LHC. In this paper, we focus our interest mainly upon the LHC forward (LHCf) experiment, giving γ-ray spectra in the very forward region with the pseudo-rapidity in the center of mass system (CMS), which have not been reported so far. We also give the pseudo-rapidity distribution of charged hadrons with obtained by ALICE and TOTEM experiments, both with LHC. We find that the revised cross-section reproduces quite well the accelerator data over the wide energy range from GeV to 30PeV for projectile protons, corresponding approximately to 100MeV to 3PeV for secondary γ-rays. The production cross-section of γ-rays produced in the forward region is essential for the study of γ-ray astronomy, while not important are those produced in the central region in CMS, and of much less importance in the backward. We discuss also the average transverse momentum of γ-rays, , and the average inelasticity transferred to γ-rays, , obtaining that the former increases very slowly with for , and the latter is almost independent of , with , while we cannot exclude the possibility of a small increase of . [Copyright &y& Elsevier]

Single particle momentum spectra are calculated within three microcanonical statistical ensembles, namely, with conserved system energy, system momentum, as well as system energy and momentum. Deviations from the exponential spectrum of the grand canonical ensemble are quantified and discussed. For mean particle multiplicity and temperature, typical for p + p interactions at the LHC energies, the effect of the conservation laws extends to transverse momenta as low as about 3GeV/c. The presented results should be considered as the next step in development of statistical models for particle production in high energy collisions. They can be useful to interpret spectra measured in nuclear collisions at high energies, in particular, their system size dependence. [ABSTRACT FROM AUTHOR]

The single-freeze-out model with parametrized hypersurface and flow geometry is employed to analyze the transverse-momentum spectra of hadrons produced in the Pb + Pb collisions at the collision energy of &radicsNN; = 2.76 TeV at the CERN Large Hadron Collider (LHC). With the notable exception for protons and antiprotons, we find a very good agreement between the model results and the data for the measured hadron species. The additional analysis of the Hanbury-Brown-Twiss (HBT) radii of pions helps us to select, from several different types of freeze-out studied in this work, the most realistic form of the freeze-out hypersurface. We find that the discrepancy ratio between the model and experiment for the proton and antiproton spectra depends on pT, dropping from 2 in the soft region to 1 around pr = 1.5 GeV. [ABSTRACT FROM AUTHOR]

Abundances of europium for 112 FGK dwarf stars of thick and thin disks have been determined in the metallicity range of −1.0 < [Fe/H] < +0.3. Spectra of the studied stars have been obtained using the 1.93-m telescope of Haute-Provence Observatory (France) with spectral resolution R = 42000 and signal-to-noise ratio S/N = 100−300. Eu content has been calculated with assumption of LTE using the synthetic spectrum approach with detailed consideration of superfine structure. Analysis of europium abundances as a function of metallicity in kinematically selected stars of the Galactic thick and thin disks revealed different values in the disks. Comparison of europium abundances with magnesium abundances makes it possible to assume that at [Fe/H] < −0.2 dex the origins of these elements are similar and at [Fe/H] > −0.2 dex they are, probably, different. [ABSTRACT FROM AUTHOR]

Thanks to its unique capabilities the ALICE experiment can measure the production of identified particles and resonances over a wide momentum range both in pp and Pb--Pb collisions at the LHC. In this report, particle-identification detectors and techniques, as well as achieved performance, are shortly reviewed. The current results on hadron transverse momentum spectra measured in pp collisions at √s = 0.9TeV and 7TeV, and in Pb--Pb collisions at √SNN = 2.76TeV are shown. In particular, proton-- proton results on particle production yields, spectral shapes and particle ratios are presented as a function of the collision energy and compared to previous experiments and commonly-used Monte Carlo models. Particle spectra, yields and ratios in Pb--Pb are measured as a function of the collision centrality and the results are compared with published RHIC data in Au--Au collisions at √SNN = 0:2TeV and predictions for the LHC. [ABSTRACT FROM AUTHOR]

The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio of events of 0.944 ± 0.016(stat) ± 0.040(syst) was obtained in 101 days of running at the Chooz nuclear power plant in France, with two 4.25 GWth reactors. The results were obtained from a single 10 m3 fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 flux measurement after correction for differences in core composition. The deficit can be interpreted as an indication of a nonzero value of the still unmeasured neutrino mixing parameter sin22&thgr;13. Analyzing both the rate of the prompt positrons and their energy spectrum, we find sin22&thgr;13 = 0.086 ± 0.041(stat) ± 0.030(syst), or, at 90% C.L., 0.017 < sin22&thgr;13 < 0.16. [ABSTRACT FROM AUTHOR]

The transverse-momentum distributions of identified hadrons produced in Pb-Pb collisions at the Large Hadron Collider (LHC) are studied in the low and intermediate range for pT < 5 GeV/c. All four spectra (π. K. p. Λ) can be well reproduced in the recombination model based on a common thermal parton distribution of light and strange quarks and on shower partons emitted in hard and semihard jets. Two essential parameters are adjusted to fit the data, one being the inverse slope of the thermal distribution and the other revealing the degree of momentum degradation in the medium. Various combinations of thermal and shower-parton components are calculated, showing the dominance of minijets. The effect of minijets is to produce harder baryons than mesons, resulting in their ratio to peak at around pT ∼ 3 GeV/c. A substantial portion of the jet energy is found to be lost to the dense medium before the partons emerge at the surface to undergo hadronization by recombination. [ABSTRACT FROM AUTHOR]

The original Standard Model has massless neutrinos, but the observation of neutrino oscillations requires that neutrinos are massive. The simple extension of adding gauge singlet fermions to the particle spectrum allows normal Yukawa mass terms for neutrinos. The seesaw mechanism then suggests an explanation for the observed smallness of the neutrino masses. After reviewing the framework of the seesaw we suggest a parametrization that directly exhibits the smallness of the mass ratios in the seesaw for an arbitrary number of singlet fermions and we present our plans to perform calculations for a process that might be studied at the LHC. [ABSTRACT FROM AUTHOR]

The article offers information on the ground-based Forier-transformed infrared solar (FTIR) absorption spectroscopy and its effectiveness in collecting data about the ozone columns in Paris, France. It mentions the FTIR's capacity to collect information on different atmospheric elements, particularly the tropospheric ozone columns. The FTIR's measurement derivation from Infrared Atmospheric Sounding Interferometer (IASI) is also discussed.

The observation of long range near side angular correlation (the so-called ridge effect) in pp collisions at the LHC is presented. Data on such correlations in heavy ion collisions at RHIC are shown. Previous informations on angular correlations in high energy pp collisions are critically reviewed. A spectrum of many recent interpretations concerning the effect is presented. [ABSTRACT FROM AUTHOR]

The article discusses the application of the information operator approach for retrieving the vertical profile information from ground-based Fourier Transform infrared (FTIR) measurements. It explores the adoption and testing of the algorithm within the retrieval code, SFIT2. It also examines the feasibility of the method when applied to FTIR spectra taken in the frame of the Network for the Detection of Atmospheric Composition Change (NDACC) at Ile de La R'eunion, France.

Abstract: We report on a first measurement of forward jet production and forward energy flow in pp collisions up to highest energies of . Inclusive spectra of jets are presented with in the region of . The energy flow in the forward region is measured for minimum bias events and for events with a high dijet in the central region. In addition, the absence of energy deposition in the forward region is used to observe diffractive events. We compare our results with predictions from Monte Carlo event generators including a simulation of multi-parton scattering. [Copyright &y& Elsevier]

Abstract: We present a measurement of the transverse momentum spectrum and of the ratio in proton-proton collisions at at the CERN LHC. In this analysis the reconstruction of and η mesons has been done via photon conversions in the central tracking system of ALICE. Therefore, this method is completely independent from the electromagnetic calorimeters. It makes the (η) measurement possible down to with a very good resolution and a very small background. For 108 pp collisions the reach is 7 GeV/c. The results are compared to NLO pQCD calculations. [Copyright &y& Elsevier]

Abstract: The ATLAS experiment has extensive charged particle tracking over full azimuth and within . The performance of this system is illustrated and some of the first results for pp collisions are presented. The prospects for tracking in the expected high-multiplicity heavy ion environment are shortly commented. The tracking performance within jets, which is essential for the measurement of jet fragmentation functions, will also be shortly presented. [Copyright &y& Elsevier]

Abstract: The LHCf experiment aims to improve knowledge of forward neutral particle production spectra at the LHC energy which is relevant for the interpretation of air shower development of high energy cosmic rays. Two detectors, each composed of a pair of sampling and imaging calorimeters, have been installed at the forward region of IP1 to measure π 0 energy spectra above 600GeV. In this paper, we present a Monte Carlo study of the π 0 measurements to be performed with one of the LHCf detectors for proton–proton collisions at TeV. In approximately 40min of operation at luminosity during the beam commissioning phase of LHC, about 1.5×104 π 0 events are expected to be obtained at two transverse positions of the detector. The backgrounds from interactions of secondary particles with beam pipes and interactions of beam particles with residual gas in the beam pipes are expected to be less than 0.1% of the signal from π 0s. We also discuss the capability of LHCf measurements to discriminate between the various hadron interaction models that are used for simulation of high energy air showers, such as DPMJET3.03, QGSJETII-03, SIBYLL2.1 and EPOS1.99. [Copyright &y& Elsevier]

Abstract: The inclusive charged particle transverse momentum distribution is measured in proton–proton collisions at at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region over the transverse momentum range . The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for is and , respectively. The data exhibit a slightly larger than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET. [ABSTRACT FROM AUTHOR]

Abstract: We present a first precision analysis of the transverse-momentum spectrum of gaugino pairs produced at the Tevatron and the LHC with center-of-mass energies of 1.96 and 10 or 14 TeV, respectively. Our calculation is based on a universal resummation formalism at next-to-leading logarithmic accuracy, which is consistently matched to the perturbative prediction at . Numerical results are given for the “gold-plated” associated production of neutralinos and charginos decaying into three charged leptons with missing transverse energy as well as for the pair production of neutralinos and charginos at two typical benchmark points in the constrained MSSM. We show that the matched resummation results differ considerably from the Monte Carlo predictions employed traditionally in experimental analyses and discuss the impact on the determination of SUSY mass parameters from derived transverse-mass spectra. We also investigate in detail the theoretical uncertainties coming from scale and parton-density function variations and non-perturbative effects. [Copyright &y& Elsevier]

The article discusses the technical aspects of the reflectometer device which was made by the French Atomic Energy Commission (CEA). The study found that the reflectance measurements of the device with eight ball bearings in different diameters have a wide range in checking the authenticity of the measure depending on the curvature radius of the measuring system. Information regarding how the reflectance and signals operate in the spherical components using spectroscopy is also elaborated.

Abstract: Bromine chemistry in the marine boundary layer is recognized to play an important role through catalytic ozone destruction, changes to the atmospheric oxidising capacity (by changing the OH/HO2 and NO/NO2 ratio) and oxidation of compounds such as dimethyl sulphide (DMS). However, the chemistry of bromine in polluted environments is not well understood and its effects are thought to be inhibited by reactions involving NO x (NO2 & NO). This paper describes long-path Differential Optical Absorption Spectroscopy (DOAS) observations of bromine oxide (BrO) at a semi-polluted coastal site in Roscoff, France. Significant concentrations of BrO (up to 7.5 ± 1.0 pptv) were measured during daytime, indicating the presence of unknown sources or efficient recycling of reactive bromine from bromine nitrate (BrONO2), which should be the major reservoir for bromine in a high NO x environment. These measurements indicate that bromine chemistry can play an important role in polluted environments. [Copyright &y& Elsevier]

Abstract: We propose a simple renormalizable left–right theory where R-parity is spontaneously broken and neutrino masses are generated through the Type I seesaw mechanism and R-parity violation. In this theory R-parity and the gauge symmetry are broken by the sneutrino vacuum expectation values and there is no Majoron problem. The and R-parity violation scales are determined by the SUSY breaking scale making the model very predictive. We discuss the spectrum and possible tests of the theory through the neutralinos, charginos, and decays at the Large Hadron Collider. [Copyright &y& Elsevier]

Abstract: Seven well-characterized clay-rocks have been taken from three test sites to perform spectral induced polarization (SIP) measurements during desiccation of these samples. These test sites include (1) the Tournemire site (IRSN) located in south of France, (2) The Bure test site (ANDRA) located in west of France, and (3) the Super-Sauze earthflow located in south western of France. We dried the samples at ambient temperature followed by heating between 65 °C and 105 °C. The quadrature conductivity, at very low-frequency, was able to discriminate between the loss of free water from the macropores and the loss of water in the micropores associated with textural changes. The calcite and quartz grain size distributions had a significant effect on the low-frequency spectrum. The inversion of our SIP data demonstrated that the generalized Cole–Cole model is an appropriate empirical and practical model for monitoring changes in water content of clay-rocks. [Copyright &y& Elsevier]

The use of zinc (Zn) isotope ratios as a tracer of anthropogenic contamination has been assessed using an extensive collection of river water samples from the Seine River basin (France) collected between 2004 and 2007. The 66Zn/64Zn ratios (expressed as δ66Zn) of dissolved Zn have been measured by MC-lCP-MS after chemical separation of Zn using an improved technique adapted to large volumes of water. Significant isotopic variations (0.07-0.58‰) occur along a transect from pristine areas of the Seine basin to the estuary and with time in Paris, and are coherent with the Zn enrichment factor. Dissolved Zn in the Seine River displays conservative behavior, making Zn isotopes a good tracer of the different sources of contamination. Dissolved Zn in the Seine River is essentially of anthropogenic origin (>90%) compared to natural sources (<7%). Roof leaching from Paris conurbation is a major source of Zn, characterized by low δ66Zn values that are distinct from other natural and anthropogenic sources of Zn. Our study highlights the absence of distinctive δ66Zn signatures of fertilizer, compost or rain in river waters of rural areas, and therefore suggests the strong retention of Zn in the soils of the Basin. Our study demonstrates that Zn isotope ratios will be a powerful new tool to trace pathways of anthropogenic Zn in the environment. [ABSTRACT FROM AUTHOR]

The article presents a case study concerning the nalbuphine misuse of a nurse in France. Analysis was performed through liquid chromatography-mass spectrometry method on urine, blood and head hair of the nurse. This method describes the criteria of nalbuphine identification and the quantity of head hair which provides evidence of chronic exposure of nalbuphine or any drug exposure by initiating historical records not possible by blood and urine analysis.

Platinum, palladium, and rhodium have been measured in fresh snow samples from 14 locations within the Aspe Valley (Pyrenees Mountains, France) during two winter seasons, February 2003 and March 2004. Ultraclean procedures were employed for the sampling, sample treatment, and analysis in order to reduce sample contamination. Possible spectral interferences on platinum group element (PGE) analysis by inductively coupled plasma mass spectrometry (ICP-MS) were controlled and corrected. The detection limits obtained were 0.05, 0.45, and 0.075 pg g-1 for Pt, Pd, and Rh, respectively. PGE content in fresh snow from the Pyrenees Mountains range from 0.20 to 2.51 pg g-1 for Pt, 1.45–14.04 pg g-1 for Pd, and 0.24–0.66 pg g-1 for Rh. The higher PGE concentration, generally measured in sites located close to road traffic, exhibit potential resuspension of PGE-enriched particles emitted locally from the car exhaust, although no direct relationship could be observed with the number of vehicles. Measured atmospheric synoptic conditions allowed identification of the origin of air masses reaching the Aspe Valley and therefore provided information about the possible sources of platinum group elements. Higher POE concentrations measured in 2004 samples, compared to the ones collected in 2003, indicate the influence of atmospheric synoptic conditions on the studied area. Fresh snow samples collected in 2003 could not be linked to a specific source, whereas 2004 samples could be influenced by PGE emissions from European vehicle fleet and Russian POE-containing mining activities. [ABSTRACT FROM AUTHOR]

The H/V spectral ratio method based on seismic noise (HVSRN) was used in the Grenoble Basin (France), an Alpine valley characterized by a small apex ratio. The resonance frequencies obtained in the experiments were compared to the thickness of the sediments deduced from a microgravimetric survey and to the 1-D theoretical assessment of site responses. Given the abundance of data on the sediments and depth of the basin, the values of the theoretical resonance frequency f o can be determined quite accurately. However, it has been observed that the effects of basin geometry can disturb f o measurements using the HVSR method, in particular for a case like the Grenoble Basin, which has a small apex ratio (w/H) and strong suspected 2-D and/or 3-D effects. Interpretation of f o values in terms of bedrock depth gives rise to estimation errors of about 10% in certain cases, with the most significant errors (>50%) occurring on the edges of the basin, where subsurface layers are characterised by larger heterogeneities and where the basin topography is accentuated. This study suggests that great care must be taken when using the HVSRN method as an exploration tool, at least in valleys with a small apex ratio. [ABSTRACT FROM AUTHOR]

In this study, charcoal-based data for Pinus cembra L . (arolla pine) were gathered from soil and travertine sequences in order to reconstruct its historical biogeography at the landscape level in the inner western Alps during the Holocene. The study sites are located between 1700 and 2990 m a.s.l., in the southern (Queyras Massif and Ubaye Valley) and the northern (Maurienne Valley) parts of the inner French Alps. Charcoal fragments were extracted from sediments by water sieving, using meshes of 5, 2, 0.8 and 0.4 mm. The charcoal mass of P. cembra was determined in each charcoal assemblage. Accelerator mass spectrometry and conventional 14C measurements were used to date the fragments. Supported by 40 14C datings, the fragments show that, over 2000 m a.s.l., P. cembra accounts for around 40% (mean value) of identified fragments. Data reveal that arolla pine once extended between 260 and 375 m above the present-day local tree lines. It was established in the southern and the northern French Alps from at least c. 9000 and 6000 cal yr bp, respectively. While present-day populations of P. cembra are very fragmented in the inner French Alps, charcoal records indicate large past occurrences of this tree since the early Holocene. Human disturbance since the Neolithic seems to be the main reason for the regression of the arolla pine woodlands. On the south-facing slopes of the study sites, currently deforested, this species extended up to 2800 m a.s.l. In the northern areas, charcoal records of the P. cembra expansion are consistent with the regional pollen archives, but in the southern massifs charcoal records indicate its presence c. 2600 years earlier than other palaeobotanical studies suggest. This discrepancy highlights the necessity to crosscheck data using several different proxies in order to assess the validity of conclusions regarding tree development in space and time. [ABSTRACT FROM AUTHOR]

Abstract: Different diagenetic transformations and their relative chronological sequence are studied in the meteoric diagenetic zone from the Upper Oligocene limestone at the North of the Aquitaine Basin (France), by combining high-resolution cathodoluminescence spectroscopy and electron-microprobe analyses. More than 128 spot analyses by electron microprobe and 60 analyses by cathodoluminescence spectroscopy are done on different meteoric cements firstly identified by classic optical microscopy. Three cement types are identified according to the relative intensity of the bands of their respective cathodoluminescence spectra (350, 380, 430, 500, and 620 nm). From these investigations, we could identify for each meteoric cement different phases of crystalline growth and crystalline dissolution. As a result, a better and more realistic meteoric diagenetic model is proposed. It illustrates the cyclic transformations from vadose zone (unsaturated) to meteoric zone (saturated). To cite this article: R. Chapoulie et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

A field experiment, conducted on a sandy, barred beach situated on the southern part of the French Atlantic coastline, allowed us to investigate the formation of secondary waves when a moderate (significant wave height of about 0.8 m in 3.7-m water depth), long (11–14 s) narrowband swell propagated over an intertidal ridge and runnel system, in both breaking and nonbreaking conditions. Field evidence using higher spectral analysis is given for the sum interactions between pairs of waves at the primary spectral peak and the consequent energy transfer to nearly harmonic wave components. Although wave breaking appears to weaken the strength of nonlinear couplings, the generation of high-frequency energy is hardly affected by wave breaking. The phenomenon of harmonic decoupling, which takes place behind the bar, cannot be completely ascribed to the increase in water depth and the so-called deshoaling effect. Indeed, the variation in the values of the maximum bicoherence was very moderate when no breaking occurred. Finally, the doubling in the number of wave crests and the consequent decrease in the significant wave period delay the energy dissipation on the beach face. [Copyright &y& Elsevier]

The article discusses the study regarding the phototransformation of 2-chloroaniline in aqueous solution, in France. The study is aimed to analyze the main photoproducts formed in aqueous solution, and to compare them with the photochemical behaviors previously published. An evaluation of the pKa from the protonated form of 2-chloroaniline was made at 2.6 from the variation of UV spectrum with pH. It was observed that after irradiation of 1 minute, in which after about 22 percent conversion, the solution was brownish, but only one main product could be observed on the HPLC chromatogram. Therefore, it was concluded that 2-chloroaniline behaves as a 2-chlorophenolate that leads to a photocontraction of the ring, in aqueous solution.