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The purpose of this research is to screen different processes that could potentially decrease or even eliminate rotenone, a toxic isoflavonoid, from Pachyrhizus seeds. Yam bean seeds have very interesting nutritional characteristics, especially their high protein and lipid contents, and could potentially increase food security in under-nourished populations. However, they contain rotenone, a natural molecule previously used as an insecticide inhibiting the respiratory mitochondrial chain. It was also proven to be toxic to mammals as chronic exposure leads to the development of Parkinson-like symptoms in rats. As the thermosensitivity of rotenone had been reported, this study tested different processes (drying, roasting, boiling, frying, alcohol extraction), tegument removal, and traditional Beninese culinary recipes. Rotenone was then quantified in end-products by a validated method, associating microwave extraction, solid phase extraction (SPE), and HPLC-UV. With these processes a rotenone removal of up to 80% was obtained. The most effective methods were the drying and roasting of the seeds and the maceration of their flour in local alcohol. Rotenone degradation and elimination were confirmed by cytotoxic assays, effectively inducing a decrease in sample toxicity.

The aim of this study was to find if fast microwave-assisted extraction could be an alternative to the conventional Soxhlet extraction for the quantification of rotenone in yam bean seeds by SPE and HPLC-UV. For this purpose, an experimental design was used to determine the optimal conditions of the microwave extraction. Then the values of the quantification on three accessions from two different species of yam bean seeds were compared using the two different kinds of extraction. A microwave extraction of 11 min at 55°C using methanol/dichloromethane (50:50) allowed rotenone extraction either equivalently or more efficiently than the 8-h-Soxhlet extraction method and was less sensitive to moisture content. The selectivity, precision, trueness, accuracy, and limit of quantification of the method with microwave extraction were also demonstrated.

This study describes the development of a validated method for the quantification of rotenone in yam bean. The milled seeds were submitted to a Soxhlet dichloromethane extraction which allowed extracting 90% of the seeds rotenone. Elimination of the lipids was obtained via solid phase extraction. Rotenone was eluted with dichloromethane/methanol and the solution dried under vacuum and solubilised directly in methanol before injection in HPLC. The whole process was realised as much as possible protected from light and at temperatures lower than 40 °C which allowed high recovery rates of spiked rotenone. Total error was used as criterion for the validation process and accuracy profiles drawn. The method allows the quantification of rotenone in yam bean seeds from 0.07% up to 1.25% (w/w). This method was applied to the quantification of rotenone in the seeds of several accessions of Pachyrhizus erosus and Pachyrhizus ahipa. The results range from 1.13 to 2.76 mg/g dry material.

Recent advancements in the development of passive millimeter and sub-millimeter wave heterodyne techniques for ground-based, air-borne, and space-borne observations of key parameters in Earth's middle atmosphere have triggered the development of adequate data analysis methods and models. This paper provides a detailed description of the versatile forward- and inversion-model for the millimeter- and sub-millimeter wavelength range, MOLIERE (v5) (Microwave Observation LIne Estimation and REtrieval, version 5). Present applications of the model include data analysis for ground-based and space-borne heterodyne instruments such as the sub-millimeter radiometer (SMR) on board the Odin satellite as well as definition studies for future limb sensors dedicated to Earth observation and Mars exploration. The physical and mathematical basics of the forward- and retrieval-model parts are presented. The main emphasis is then put on the description of the numerical implementation of the algorithms for radiative transfer and weighting function computations as well as on the employed method for modeling atmospheric refraction.

The Sub‐Millimetre Radiometer (Odin/SMR) on board the Odin satellite, launched on 20 February 2001, performs regular measurements of the global distribution of stratospheric nitrous oxide (N2O) using spectral observations of the J = 20 → 19 rotational transition centered at 502.296 GHz. We present a quality assessment for the retrieved N2O profiles (level 2 product) by comparison with independent balloonborne and aircraftborne validation measurements as well as by cross‐comparing with preliminary results from other satellite instruments. An agreement with the airborne validation experiments within 28 ppbv in terms of the root mean square (RMS) deviation is found for all SMR data versions (v222, v223, and v1.2) under investigation. More precisely, the agreement is within 19 ppbv for N2O volume mixing ratios (VMR) lower than 200 ppbv and within 10% for mixing ratios larger than 150 ppbv. Given the uncertainties due to atmospheric variability inherent to such comparisons, these values should be interpreted as upper limits for the systematic error of the Odin/SMR N2O measurements. Odin/SMR N2O mixing ratios are systematically slightly higher than nonvalidated data obtained from the Improved Limb Atmospheric Spectrometer‐II (ILAS‐II) on board the Advanced Earth Observing Satellite‐II (ADEOS‐II). Root mean square deviations are generally within 23 ppbv (or 20% for VMR‐N2O > 100 ppbv) for versions 222 and 223. The comparison with data obtained from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the Envisat satellite yields a good agreement within 9–17 ppbv (or 10% for VMR‐N2O > 100 ppbv) for the same data versions. Odin/SMR version 1.2 data show somewhat larger RMS deviations and a higher positive bias.

The differential scaning calorimetry study of the compound of formula CH3NH3PbCl3 in the temperature range 168 K–181 K shows two phase transitions according to the phase sequence: phase III (P2221) ← (172K) → phase II (P4/mmm) ← (179K) → phase I (Pm3m) These transitions were characterized by X-ray diffraction, DSC and Raman scattering. The III transition involves mainly the rotational and orientational motions of the organic cation, whereas the antiferroelectric transition at 172K is connected with a complex mechanism involving the freezing of the cation motions coupled with the distorsion of the PbCl6 octahedra This sequence has been also analysed in terms of pseudo-spin theory.

Raman spectra of polycrystalline samples of CH3NH3PbCl3 were studied at temperature ranging from 80 K to 300 K. An assignment of most of the observed bands is proposed. The first order phase transitions previously detected at 172 and 179 K were characterized: III←(172 K )→II←(179 K )→I (P222 1 ) (P4/mmm) (Pm3m) The spectral evolution and the mechanism proposed is in agreement with the theoretical analysis of normal vibrations and with previous X-ray diffraction studies and dielectric measurements. The I ↔ II transition involves mainly the conformational and orientational motions of the organic cation, whereas the antiferroelectric transition at 172 K is connected with a complex mechanism involving the freezing of the cation motions coupled with the distorsion of the PbCl6 octahedra. A systematic measurement of the CH3NH3+ torsional vibration (at 483 cm−1) was performed and the activation energy Ea = 10.1 kJ mol−1 was extracted from the half width vs temperature curve.

The purpose of the research was to develop and validate a rapid quantification method able to screen many samples of yam bean seeds to determine the content of two toxic polyphenols, namely pachyrrhizine and rotenone. The analytical procedure described is based on the use of an internal standard (dihydrorotenone) and is divided in three steps: microwave assisted extraction, purification by solid phase extraction and assay by ultra high performance liquid chromatography (UHPLC). Each step was included in the validation protocol and the accuracy profiles methodology was used to fully validate the method. The method was fully validated between 0.25 mg and 5 mg pachyrrhizin per gram of seeds and between 0.58 mg/g and 4 mg/g for rotenone. More than one hundred samples from different accessions, locations of growth and harvest dates were screened. Pachyrrhizine concentrations ranged from 3.29 mg/g to lower than 0.25 mg/g while rotenone concentrations ranged from 3.53 mg/g to lower than 0.58 mg/g. This screening along with principal component analysis (PCA) and discriminant analysis (DA) analyses allowed the selection of the more interesting genotypes in terms of low concentrations of these two toxic polyphenols.

Four crystalline phases (called III, II, and I) have been observed in the perovskite-type layer compound using differential scanning calorimetry, x-ray diffraction and spectroscopic studies. The crystallographic evolution with increasing temperature appears to be triclinic . An intermediate disordered phase II', stable in a narrow temperature range and structurally similar to phase II, has also been observed, such that the transformation proceeds, in fact, two steps . Phase III, stable at low temperature, has an ordered structure. The phase transition , which is of first-order type, corresponds to an order - disorder mechanism involving the organic part of the structure (alkylammonium chains) and deformation of octahedra. The phase transition , which is of second-order type, is related to the arrangement of octahedra of perovskite layers. The transition is of first-order type and involves conformational disorder of the chains. In phase I chain melting sets in.

The infrared solid state, Raman solid state and tetrachloride solution spectra of flavone have been obtained. Assignments of most of the vibrational data have been performed by comparison between the spectra of flavone and three isotopic species, deuterated on the A, B and C rings, respectively. The vibrational frequencies for all the investigated compounds have been calculated from the conformational analysis of flavone using the semi-empirical AM1 method and compared with experimental values. The correlation is more or less satisfactory; however, for some vibrational modes, the calculated isotopic shifts agree better with experiment than do the frequencies themselves. Specific vibrational modes which retain a benzene ring mono-substituted and ortho-distributed character have been recognized in the spectra, according to literature data, isotopic frequency shifts and graphic representation of the atomic displacements.

In order to give a better insight into the vibrational properties of anthocyanins, the synthesis and the vibrational studies of some hydroxyflavylium derivatives with a controlled substitution pattern have been performed. The IR, Raman and resonance Raman spectra of the investigated hydroxyflavylium compounds have been recorded in the solid and solution states. A number of lines have been assigned on the basis of deuterium isotopic shifts, resonance enhancement and previous studies on parent compounds. An attempt has been made to analyze the influence of hydroxy substituents on vibrational properties of the investigated flavylium cations.

Deuterated thiophene has been studied by powder neutron diffraction spectroscopy from ∼ 60 K to melting temperature. Preliminary DSC measurements have shown that the thermodynamic behaviours of hydrogenated and deuterated thiophene are almost identical, so that the conclusions drawn from the present structural studies of C 4 D 4 S are valid for both compounds. The structures of stable phases IV and V have been observed for the first time: phase V lattice is obtained by multiplying by 2 parameter c of orthorhombic phase III and has been assigned space group P2 1 ma; phase IV also corresponds to a superstructure of phase III, but, as expected because of the quasi-fivefold molecular symmetry and of its reorientational dynamics, it can be thought to be an incommensurate phase.

Butylenediammonium lead tetrachloride exhibits three structural phase transitions according to the sequence I-(324 K) to gamma to (341 K) to beta to (420 K) to alpha . These transitions are characterized by DSC measurements and Raman scattering on polycrystalline samples. The space groups and the cell parameters of I, gamma and beta phases were determined by X-ray diffraction on single crystals and powder samples. The three phases I, gamma and beta have the same space group P21/c with Z = 4. The first-order phase transition at 324 K is driven by orientational and conformational motions of the butylenediammonium chains. The transition at 341 K is also of first-order type and involves both organic cation motions and PbCl6 octahedra deformations. The transition at 420 K was evidenced by Raman scattering; it leads to a plastic phase similar to that observed in the homologous monoammonium compound (C3H7NH3)2PbCl4. This transitional behaviour and the crystal dynamics will be discussed and compared with those of homologous compounds.

The structures of Li and K methyl and tert-butyl phenylacetate enolates A,M and B,M have been examined by IR and 13 C NMR spectroscopy in different solvents and solvent mixtures. In the IR, coupling of aromatic ring mode with the v(C . - . O) stretching vibration allows assignment of the E (or Z) configuration to the corresponding enolate. The IR mode assignments are secured by specific deuteration of the phenyl or methyl moieties in methyl phenylacetate.

Low-frequency Raman spectra (5–250 cm−1) of a polycrystalline sample of bis(n-propylammonium) lead tetrachloride were recorded at different temperatures between 4 and 300 K. A new first-order reentrant phase transition was observed near 35 K. The phase diagram is: Both phases II and IV present the same degree of disorder and are believed to be isomorphic with a monoclinic cell symmetry. Spectral evolution analysis and analogy with a manganese homologous compound suggest an incommensurate character for phase III between 35 K and 91 K. The pseudo-phase mode characteristic of the incommensurability was identified at about 10 cm−1

The Raman spectra (260-10 cm −1 ) and differential scanning calorimetry of polycrystalline samples of (C 3 H 7 NH 3 ) 2 PbCl 4 were investigated in the temperature range 300–450 K. This work shows three first-order phase transitions I → γ → β → α, respectively at 340 K (Δ H 1 = 3.73 kJ mol −1 ), 371 K (Δ H 2 = 0.22 kJ mol −1 ) and 406 K (Δ H 3 = 0.25 kJ mol −1 ). The thermal behaviour and crystal structure analogy with the Mn derivative suggest an incommensurability of the γ phase, embedded between two commensurate phases I and β, both belonging to the same space group. The phase transition I → γ is governed by an order-disorder mechanism involving mainly alkylammonium chains; the other transitions are driven by displacive mechanisms involving deformation of PbCl 6 octahedra. The highest temperature phase α seems to be a plastic phase.

Picolines and 2,6-lutidines partially deuterated on the methyl group or fully deuterated have been prepared with high isotopic purity. Monodeuteration of the methyl group was obtained either by deuterolysis of lithiated derivatives or by reduction of CH2X group with Bu3SnD. Dideuteriomethyl compounds were synthesized by reduction of the corresponding esters with LiAlD4 and conversion of the alcohol to chloromethyl derivatives which were finally reduced by an acetic acid-zinc mixture. Exchanges with heavy water on platinum yield γ-picoline-D7 and 2,6-lutidine-D9.

Gas-phase infrared and Raman spectra of the three isomeric selectively deuteratedγ-, β- and α-picolines (C5ND4CHD2) were recorded in the CH stretching region. They are each characterized by a strong band and a weaker band at a lower frequency, the intensity of which increases progressively from the Para (γ-) to the ortho (α-) isomer. These bands exhibit simple Raman profiles but their infrared contours are of A and C type, respectively. A quantum treatment of these spectra, assuming an anharmonic coupling of the ν(CH) mode with the internal rotation of the CHD2 group, is developed in the adiabatic approximation. This model leads to a good fit of the experimental Raman band shapes and a good picture of the observed infrared spectra. The frequency of the intense band is assigned to the frequency of the ν(CH) mode during the almost free rotation of the CHD2 group; the weaker band corresponds to the frequency of the CH bond in the plane perpendicular to the pyridine ring (γ-picoline) or in a plane tilted by about ± 120° from the pyridine ring (β- and α-picoline). The frequency difference between ν∥(CH in the molecular plane) and ν⟂ (CH in the plane perpendicular to the molecular plane) is found to increase from γ- to α-picoline, as does the internal rotation barrier height; the most stable conformations of the methyl group with respect to the pyidine ring are thus determined. These results provide new evidence for the importance of hyperconjugation effects in such methylated aromatic molecules.

Some physico-chemical processes taking place at a sliding CaTiO/sub 3/-ceramic/unlubed carbon-film interface of a rigid disk drive are described. A major cause of frictional buildup is the tribochemical wear of the carbon surface atoms in the oxygen-containing atmosphere. Based on indirect evidence, a mechanism involving oxygen chemisorption on surface dangling bonds and CO/CO/sub 2/ desorption under the sliding motion of the read/write head is proposed. Raman data providing evidence of the formation of a graphite transfer film at the interface of some carbon films are shown. Catalytic activity of the slider ceramic towards oxidation is also demonstrated. Methods for slowing down the frictional-buildup process are discussed. They include heavier texture, carbons with higher sp/sup 3//sp/sup 2/ ratio, active sites blocking, and application of topical lubricant. >

The airborne submillimeter radiometer ( ASUR) was deployed onboard the Falcon research aircraft during the scanning imaging absorption spectrometer for atmospheric cartography ( SCIAMACHY) validation and utilization experiment ( SCIAVALUE) and the European polar stratospheric cloud and lee wave experiment ( EuPLEx) campaigns. A large number of ozone profile measurements were performed over a latitude band spanning from 5 degrees S to 80 degrees N in September 2002 and February/March 2003 during the SCIAVALUE and around the northern polar latitudes in January/February 2003 during the EuPLEx. Both missions amassed an ample microwave ozone profile data set that is used to make quantitative comparisons with satellite measurements in order to assess the quality of the satellite retrievals. In this paper, the ASUR ozone profile measurements are compared with measurements from SCIAMACHY and Michelson interferometer for passive atmospheric sounding ( MIPAS) on Environmental Satellite and optical spectrograph and infrared imager system ( OSIRIS) and submillimeter radiometer ( SMR) on the Odin satellite. The cross comparisons with the criterion that the ASUR measurements are performed within +/- 1000 km and +/- 6 hrs of the satellite observations show a good agreement with all the four satellite sensors. The differences in data values are the following: -4 to +8% for ASUR-SCIAMACHY ( operational product, v2.1), within +/- 15% for ASUR-SCIAMACHY ( scientific product, v1.62), up to +6% for ASUR-MIPAS ( operational product v4.61) and ASUR- MIPAS ( scientific product v1-O(3)-1), up to 17% for ASUR- OSIRIS ( v012), and -6 to 17% for ASUR- SMR ( v222) between the 20- and 40- km altitude range depending on latitude. Thus, the intercomparisons provide important quantitative information about the quality of the satellite ozone profiles, which has to be considered when using the data for scientific analyses.

Water vapour plays an important role for the chemistry and dynamics of the atmosphere. It is a strong greenhouse gas in the troposphere and contributes to cooling in the stratosphere. As the main source of chemically active HOx radicals, it is linked to many photo-chemical cycles controlling the composition of the middle atmosphere. In order to improve our knowledge of the amount and variability of water in the middle atmosphere, the Sub-Millimetre Radiometer (SMR) on board the Odin satellite, launched in February 2001, observes several thermal emission lines of water vapour in the 486–581 GHz spectral range from the Earth's limb. Bands centred at 488.9 and 490.4 GHz are used to study water vapour and its isotopes, on the basis of four observation days per month. Vertical profiles of View the MathML source, View the MathML source, and HDO are retrieved between roughly 20 and 70 km in the stratosphere and mesosphere. A strong water vapour line at 556.9 GHz is simultaneously measured in a second band, providing information in the mesosphere and lower thermosphere between about 40 and 100 km. Measurements of View the MathML source at 552.0 GHz in monthly intervals complete the picture of middle atmospheric water vapour provided by Odin/SMR. The measurements of the isotope HDO in the 20–70 km altitude range allow to study the isotopic ratio of deuterium in stratospheric water vapour (D/H), potentially supplying information on the origin of stratospheric water vapour: transport of tropospheric air through the tropical tropopause layer (TTL) versus in situ chemical production such as from methane oxidation. The unique measurements of the molecules View the MathML source and View the MathML source containing heavy isotopes of oxygen may provide a crucial test for our understanding of the complex chemical reaction mechanisms controlling the exchange of oxygen between water vapour and ozone.

International audience; The Airborne Submillimetre Radiometer (ASUR) was deployed onboard theFalcon research aircraft during the SCIAVALUE (SCIAMACHY-SCanning Imaging Ab-4 sorption SpectroMeter for Atmospheric CartograpHY-Validation and Utilization Exper-5 iment) and EuPLEx (European Polar and Lee wave Experiment) campaigns. A large num-6 ber of ozone profile measurements were performed over a latitude band spanning from7 5

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The Sub-Millimetre Radiometer (SMR) on board the Odin satellite, launched on 20 February 2001, observes key species with respect to stratospheric chemistry and dynamics such as O-3, ClO, N2O, and HNO3 using two bands centered at 501.8 and 544.6 GHz. We present the adopted methodology for level 2 processing and the achieved in-orbit measurement capabilities of the SMR radiometer for these species in terms of altitude range, altitude resolution, and measurement precision. The characteristics of the relevant level 2 data versions, namely version 1.2 of the operational processor as well as versions 222 and 223 of the reference code, are discussed and differences are evaluated. An analysis of systematic retrieval errors, resulting from spectroscopic and instrumental uncertainties, is also presented.

We use measurements of chlorine monoxide (ClO) by the SMR instrument onboard the Odin satellite to study the nighttime thermal equilibrium between ClO and its dimer Cl2O2. Observations performed in the polar vortex during the 2002-2003 Arctic winter showed enhanced amounts of nighttime ClO over a wide range of stratospheric temperatures (185 < T < 225 K). Odin/SMR measurements are here compared to three-dimensional model calculations using various published estimations of the K-eq equilibrium constant between ClO and Cl2O2. Our results show that the value of K-eq currently recommended by JPL (Sander et al., 2003) leads to a large underestimation of the observed nighttime ClO amounts, and that a realistic estimation of K-eq must lie between the values determined by Cox and Hayman (1988) and Von Hobe et al. (2005).

In September 2002 the Antarctic polar vortex split in two under the influence of a sudden warming. During this event, the Odin satellite was able to measure both ozone (O3) and chlorine monoxide (ClO), a key constituent responsible for the so-called “ozone hole”, together with nitrous oxide (N2O), a dynamical tracer, and nitric acid (HNO3) and nitrogen dioxide (NO2), tracers of denitrification. The submillimeter radiometer (SMR) microwave instrument and the Optical Spectrograph and Infrared Imager System (OSIRIS) UV-visible light spectrometer (VIS) and IR instrument on board Odin have sounded the polar vortex during three different periods: before (19–20 September), during (24–25 September), and after (1–2 and 4–5 October) the vortex split. Odin observations coupled with the Reactive Processes Ruling the Ozone Budget in the Stratosphere (REPROBUS) chemical transport model at and above 500 K isentropic surfaces (heights above 18 km) reveal that on 19–20 September the Antarctic vortex was dynamically stable and chemically nominal: denitrified, with a nearly complete chlorine activation, and a 70% O3 loss at 500 K. On 25–26 September the unusual morphology of the vortex is monitored by the N2O observations. The measured ClO decay is consistent with other observations performed in 2002 and in the past. The vortex split episode is followed by a nearly complete deactivation of the ClO radicals on 1–2 October, leading to the end of the chemical O3 loss, while HNO3 and NO2 fields start increasing. This acceleration of the chlorine deactivation results from the warming of the Antarctic vortex in 2002, putting an early end to the polar stratospheric cloud season. The model simulation suggests that the vortex elongation toward regions of strong solar irradiance also favored the rapid reformation of ClONO2. The observed dynamical and chemical evolution of the 2002 polar vortex is qualitatively well reproduced by REPROBUS. Quantitative differences are mainly attributable to the too weak amounts of HNO3 in the model, which do not produce enough NO2 in presence of sunlight to deactivate chlorine as fast as observed by Odin.

A method for assimilating observations of long-lived species such as ozone (O-3) and nitrous oxide (N2O) in a three-dimensional chemistry transport model (3D-CTM) is described. The model is forced by the temperature and wind analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF). The O-3 and N2O fields used in this study are obtained from the Sub-Millimeter Radiometer (SMR) aboard the Odin satellite. The assimilation technique used is the sequential statistical interpolation approach. The parametrization of the error covariance matrix of the model forecast field is described. A sensitivity study of the system parameters is done in terms of the OMF (observation minus forecast) vector also called "innovation'' vector and in terms of the chi(2) (chi-square) test. The effect of the correlation distances is critical for the assimilated field. The RMS ( root mean square) of the OMF for the correlation distances is minimal for values of 1500 km in the meridional direction and 500 km in the zonal direction for both O-3 and N2O. The treatment of the meridional distance as a function of latitude does not reveal an important improvement. The chi(2) diagnostic shows that the asymptotic value of the model error ( the model error of saturation) is optimal for the value of 12.5% for O-3 and 18% for N2O. We demonstrate the applicability of the developed assimilation method for the Odin/SMR data. We also present first results of the assimilation of Odin/SMR ozone and nitrous oxide for the period from 22 December 2001 to 17 January 2002.

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The Odin satellite carries two instruments measuring ozone spectra from which strato- spheric ozone profiles are retrieved. Onboard Odin, the Sub-Millimeter Radiometer (SMR) measures an ozone spectral line at 501.4 GHz. Forward model and inversion codes using the Optimal Estimation Method permit the retrieval of vertical profiles in the altitude range 20-65 km. The UV-visible spectrograph of the OSIRIS instru- ment measures ozone absorption limb spectra in the ranges 300-340 and 400-700 nm. A code based on the technique described by Flittner et al. (2000) and McPeters et al. (2000) provides vertical profiles from 20 to 60 km. This work presents a comparison of Odin ozone profiles with those obtained by ground-based measurements from primary or complementary stations of the Network for the Detection of Stratospheric Change (NDSC) such as lidars, microwave radiometers and ozonesondes. Some additional comparisons are also performed with ozone profiles obtained by balloon flights, air- craft experiments, other satellite measurements and model computations. These largesets of comparisons is also used to confirm the soundness of the Odin ozone measure- ments.