Real-time increase in depth of field of an uncooled thermal camera using several phase-mask technologies

Imaging systems that combine a phase mask in the pupil and digital postprocessing may have better performance than conventional ones. We have built such a system to enhance the depth of field of an uncooled thermal camera. The phase masks are binary, their structures are optimized thanks to an image quality criterion, and they have been realized with three different technologies that give equivalent results. The deconvolution postprocessing is performed in real time with a graphics processing unit. A significant increase of the depth of field of a factor 3 has been obtained.     

Adult zebrafish as a model organism for behavioural genetics

Recent research has demonstrated the suitability of adult zebrafish to model some aspects of complex behaviour. Studies of reward behaviour, learning and memory, aggression, anxiety and sleep strongly suggest that conserved regulatory processes underlie behaviour in zebrafish and mammals. The isolation and molecular analysis of zebrafish behavioural mutants is now starting, allowing the identification of novel behavioural control genes. As a result of this, studies of adult zebrafish are now helping to uncover the genetic pathways and neural circuits that control vertebrate behaviour.     

57Fe Mössbauer study of the electrochemical reaction of Li with FeP y (y = 1,2)

A complete ⁵⁷Fe Mössbauer study was undertaken to elucidate the electrochemical mechanism occuring during the cycling of the FeP _x (x?= 1,2)/Li batteries. Upon discharge, for FeP, the conversion reaction FeP + 3Li → Fe + Li₃P was confirmed, whereas for FeP₂, FeP and a disordered magnetic unknown phase A are observed. On charge, the starting material is partially reconstructed only in the case of FeP. Once the first cycle is achieved, the same redox process occurs in both the FeP/Li and FeP₂/Li cells, between LiFeP, FeP, Fe° (or phase A) and Li₃P.     

Electrolyte based on fluorinated cyclic quaternary ammonium ionic liquids

Ionic liquids, ILs, based on fluorinated pyrrolidinium and piperidinium ammonium cations and imide anion were prepared and characterized. The physicochemical and electrochemical properties of these ILs including melting point, glass transition and degradation temperatures, viscosity, ionic conductivity, and electrochemical stability were determined and compared to alkyl pyrrolidinium and piperidinium ILs. The incorporation of a CF₃ group instead of a CH₃ induces an increase of the IL viscosity, thus a conductivity decrease. However, good ionic conductivity is obtained with fluorinated pyrrolidinium IL. Cyclic amine ILs with propyl alkyl chain or fluorinated ammonium exhibit very high electrochemical stability toward oxidation. The effect of the addition of LiTFSI on the IL properties was studied with the same methodology.     

The electrochemical reactivity of the NiP<Subscript>3</Subscript> skutterudite-type phase with lithium

We report the electrochemical Li reactivity of the cubic NiP₃ phase, a candidate for anode applications for Li-ion batteries. NiP₃ reacts with nine lithium per formula unit leading to a first cycle reversible capacity of 1,475 mAh/g at an average potential of 0.9 V vs. Li+/Li°. Electrochemical measurements and complementary X-ray diffraction showed that NiP₃ presents a conversion process competing with an insertion process. A good cycleability may only be obtained on a limited potential window, excluding the low-potential region. This paper was presented at the 11th EuroConference on the Science and Technology of Ionics, Batz-sur-Mer, Sept. 9–15, 2007.     

Spectroscopic Properties and Laser Induced Fluorescence Determination of Some Endocrine Disrupting Compounds

This work presents spectroscopic properties of some Endocrine Disrupting Compounds (EDCs), frequently found in food and in natural water. Studied molecules belong to the groups of phenolic and phthalate EDCs. In a first part, we have examined their absorption and fluorescence properties. Fluorescence emission wavelengths are about 300 nm for phenolic compounds and 360 nm for phtalate compounds; main excitation wavelengths being comprised between 210 nm and 230 nm. Fluorescence lifetimes measured are short (about 4 ns) and the fluorescence quantum yield has been determined. In a second part, to avoid the time consuming solvent extraction step, an analytical application to evaluate the performance of a direct analysis by laser induced fluorescence spectroscopy of ECDs traces in tap water and in raw water is presented. Good detection limits have been obtained, i.e.: 0.35 μg.L⁻¹ of chlorophenol in tap water, which are always lower than the reported Predictive Non Efficient Concentration (PNEC).     

Progress in the lithium insertion mechanism in Cu3P

Copper phosphide, Cu₃P has been synthesized using a ceramic route, and its electrochemical behaviour versus lithium has been studied studied galvanostatic and potentiodynamic measurements and in situ X-ray diffraction analysis. The insertion/extraction mechanism proceeds with the formation of at least three different Li_xCu_3−xP (x=1, 2, 3) phases. The electrochemical behaviour of Cu₃P samples obtained from ceramic and solvothermal syntheses are compared to further understanding of the complex redox mechanism occurring during insertion/extraction. First-principle electronic structure calculations show that discharge probably begins with the formation of a solid solution Li_xCu_3−yP (x<0.5). Paper presented at the Patras Conference on Solid State Ionics-Transport Properties, Patras, Greece, Sept. 14 – 18, 2004.     

Small dissymmetry,yet large effects on the transport propertiesof electrolytes based on imide salts: Consequences on performancein Li-ion batteries

To gain better insight into the influence of the anion size and symmetry on the transport properties and thermal stability of an electrolyte based on lithium(fluorosulfonyl)(trifluoromethanesulfonyl)-imide(FTFSI)salt,we performed the physical and electrochemical characterization of an electrolyte based on FTFSI incorporated in standard binary(3 EC/7 EMC)and ternary(EC/PC/3 DMC)alkylcarbonate mixtures.By applying the Jones-Dole-Kaminsky(JDK),Eyring and Arrhenius empirical models to the electrolyte viscosity we show that the activation enthalpy and entropy energy barriers(ΔH≠,ΔS≠)for viscous flow are between 12 and 15 kJ·mol^-1.They are strongly dependent on the solvent nature and are significantly lower than their symmetric anions LiFSI and LiTFSI(19-20 kJ·mol^-1)in the binary mixture.Furthermore,the hydrodynamic radius,rs,calculated by JDK,and the ionicity behavior illustrated by the Walden role,showed that the FTFSI anion is outside the solvation sphere(rs>0.6 nm)which is smaller in the case of an EC/EMC solvent base.In the 3 EC/7 EMC solvent mixture,LiFTFSI is less conductive than in the ternary mixture i.e.,σ_max=8.9 mS cm^-1 at C_max=1.1 mol L^-1 for 3 EC/7 EMC and,σ_max=10.5 mS cm^-1 at max=0.7 mol L^-1 for EC/PC/3 DMC,due to a strong solvation and a greater association of FTFSI ions in the binary solvent mixture.The thermal stability of FTFSI based electrolytes was determined by the shift of the evaporation temperature of the volatile solvents(DMC,EMC)in the presence of salt,towards the higher temperatures.This feature is visible on the thermograms obtained by DSC both with the liquid electrolyte and with charged LMO cathodes in presence of electrolytes.The consequences of these properties on the electrochemical behavior of a graphite(Gr)half-cell,a lithium metal(Li)anode and a manganese lithium oxide(LMO)cathode demonstrated on the one hand the formation of a thick solid electrolyte interphase(SEI)on graphite that consumed a significant amount of lithium i.e.,18%of total capacity of the first charge.Furthermore,LiFTFSI delivered 95%of the initial capacity C=360 mAh g^-1 at C/10 with EC/PC/3 DMC versus 91%when it was combined with 3 EC/7 EMC C=348 mAh g^-1,while the capacities obtained for LiTFSI in EC/PC/3 DMC were the lowest(C=275 mAh g^-1)compared to those of the other salts.After 10 cycles,the capacity loss at C/20 is<2%for LiFSI and LiFTFSI with the two solvent mixtures.On the other hand,manganese dissolution from LMO as well as current collector corrosion were confirmed by post-mortem examination of opened coin cells.The incompatibility of the LMO cathode with an electrolyte based on FTFSI was confirmed by the position of the decomposition peak of charged LMO in contact with this electrolyte observed by DSC These results demonstrate that the nature of the anion as well as the composition of the solvent considerably influence the performance of imide-based lithium salts both on the anode,but especially on the high voltage cathode.     

Capillary HPLC–ICP MS mapping of selenocompounds in spots obtained from the 2-D gel electrophoresis of the water-soluble protein fraction of selenized yeast

A method based on ICP collision-cell MS detection in capillary HPLC was developed to gain an insight into the purity and identity of selenium-containing proteins separated by 1-D and 2-D electrophoresis. The bands and spots obtained after the separation of water-soluble proteins in selenized yeast were digested with trypsin prior to chromatography. Selenium could be detected down to the subpicogram level. The method, assisted by information obtained by MALDI TOF MS on the 5000 Da cut-off fraction, permitted the purity of bands and spots to be estimated and the efficiency of tryptic digestion and the quantity of selenium present in individual peptides to be evaluated. Owing to the high sensitivity and the lack of matrix suppression effects, the method provided chromatograms with signal-to-noise ratios of 10–1000 in conditions where the common ES Q–TOF MS detection failed.