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Nano-confinement of biomolecules： Hydrophilic confinement promotes structural order and enhances mobility of water molecules

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Nano Research 2016年第2期9卷 273-281页

作者： Bachir Aoun Daniela Russo Argonne National Laboratory Chicago IL 60439 USA CNR-IOM c/o Institut Laue-Langevin 38400 Grenoble France institut Lumiere Matiere Universite de Lyon 69622 Lyon France

Molecular dynamics simulations have been used to investigate the confinement packing characteristics of small hydrophilic （N-acetyl-glycine-methylamide, Nagma） and hydrophobic （N-acetyl-leucine-methylamide, Nalma） biomolecules in large diameter single-wall carbon nanotubes （SWCNTs）. We find that hydrophilic biomolecules easily fill the nanotube and self organize into a geometrical configuration which reminds the water structural organization under SWCNT confinement. The packing of hydrophilic biomolecules inside the cylinder confines all water molecules in its core, which enhances their mobility. Conversely, hydrophobic biomolecules accommodate into the nanotubes with a trend for homogeneous filling, which generate unstable small pockets of water and drive toward a state of dehydration. These results shed light on key parameters important for the encapsulation of biomolecules with direct relevance for long-term storage and prevention of degradation.

关键词： nano-confinement protein folding hydration water carbon nanotube drug delivery

SEPARATION OF SCALES IN ELASTICITY IMAGING:A NUMERICAL STUDY

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Journal of Computational Mathematics 2010年第3期28卷 354-370页

作者： Habib Ammari Pierre Garapon Franois Jouve institut langevin Laboratoire Ondes et Acoustique Laboratoire J.L.Lions Universite Paris Ⅶ Laboratoire J.L.Lions Université Paris Ⅶ

In magnetic resonance elastography, one seeks to reconstruct the shear modulus from measurements of the displacement field in the whole body. In this paper, we present an optimization approach which solves the problem by simply minimizing a discrepancy functional. In order to recover a complex anomaly in a homogenous medium, we first observe that the information contained in the wavefield should be decomposed into two parts, a ＂near-field＂ part in the region around the anomaly and a ＂far-field＂ part in the region away from the anomaly. As will be justified both theoretically and numerically, separating these scales provides a local and precise reconstruction.

关键词： Elastography multi-scale imaging anomaly reconstruction.

Shaping the light amplified in a multimode fiber

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Light(Science & Applications) 2016年第1期5卷 250-258页

作者： Raphael Florentin Vincent Kermene Joel Benoist Agnès Desfarges-Berthelemot Dominique Pagnoux Alain Barthélémy Jean-Pierre Huignard XLIM Research institute Universitéde Limoges-Centre National de la Recherche ScientifiqueUMR 625287060 LimogesFrance institut langevin ESPCI-ParisTech75238 ParisFrance

Propagation of light in multimode optical fibers usually gives a spatial and temporal randomization of the transmitted field similar to the propagation through scattering *** still applies when scattering or multimode propagation occurs in gain *** demonstrate that appropriate structuration of the input beam wavefront can shape the light amplified by a rareearth-doped multimode *** of the wavefront was achieved by a deformable mirror in combination with an iterative optimization *** present experimental results and simulations showing the shaping of a single sharp spot at different places in the output cross-section of an ytterbium-doped fiber *** and narrowing of the amplifier far-field pattern was realized as *** the wavefront to shape the amplified light can also serve to improve the effective *** shaping approach still works under gain saturation,showing the robustness of the *** and experiments attest that the shaping is effective even with a highly multimode fiber amplifier carrying up to 127 modes.

关键词： adaptive optics amplification beam shaping complex media multimode optical fiber

Design,synthesis and performance of Ba-doped derivatives of SrMo_(0.9)Fe_(0.1)O_(3-δ)perovskite as anode materials in SOFCs

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Journal of Materiomics 2019年第2期5卷 280-285页

作者： S.Sydyknazar V.Cascos M.T.Fernandez-Diaz J.A.Alonso instituto de Ciencia de Materiales de Madrid C.S.I.C.CantoblancoE-28049MadridSpain institut Laue langevin BP 156XGrenobleF-38042France

The oxides SrMo_(1-x)Fe_(x)O_(3-δ)(x=0.1 and 0.2)have recently been described as excellent anode materials for solid-oxide fuel cells at intermediate temperatures(IT-SOFC)with LSGM as the *** this work we have partially replaced Sr by Ba in a compound of formula Sr_(0.9)Ba_(0.1)Mo_(0.9)Fe_(0.1)O_(3-δ),in order to expand the unit-cell size and thereby improve the ionic diffusion of O^(2-)ions through the crystal *** anode materials must be stable under reducing conditions,since they work in the presence of the fuel(H_(2))at elevated *** anodes are inspired in the SrMoO_(3)perovskite,which contains Mo4+ions,stable in very reducing *** novel oxide has been structurally characterized from x-ray(XRD)and neutron powder diffraction(NPD)data;the structure is defined at room temperature in the Pm-3m space group,and shows oxygen vacancies,necessary for the performance of this material as mixed ionic-electronic(MIEC)*** single test cells supported on LSGM,the materials generated output powers close to 500 mW/cm^(2)at 850℃using pure H_(2)as *** thermal expansion is linear,with TEC=10.93×10^(-6)K^(-1).The chemical compatibility with the LSGM electrolyte was also verified.

关键词： IT-SOFC Anode Perovskite Neutron diffraction SrMoO_(3)

Single-emitter super-resolved imaging of radiative decay rate enhancement in dielectric gap nanoantennas

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Light(Science & Applications) 2024年第1期13卷 47-54页

作者： R.Margoth Córdova-Castro Bart van Dam Alberto Lauri Stefan A.Maier Riccardo Sapienza Yannick De Wilde Ignacio Izeddin Valentina Krachmalnicoff institut langevin ESPCI ParisPSL UniversityCNRSParisFrance The Blackett Laboratory Department of PhysicsImperial College LondonLondonUK School of Physics and Astronomy Monash UniversityClaytonVictoriaAustralia Chair in Hybrid Nanosystems Ludwig-Maximilians Universität MünchenMuenchenGermany Department of Physics University of OttawaOttawaONCanada

High refractive index dielectric nanoantennas strongly modify the decay rate via the Purcell effect through the design of radiative *** to their dielectric nature,the field is mainly confined inside the nanostructure and in the gap,which is hard to probe with scanning probe *** we use single-molecule fluorescence lifetime imaging microscopy(smFLIM)to map the decay rate enhancement in dielectric GaP nanoantenna dimers with a median localization precision of 14 *** measure,in the gap of the nanoantenna,decay rates that are almost 30 times larger than on a glass *** comparing experimental results with numerical simulations we show that this large enhancement is essentially radiative,contrary to the case of plasmonic nanoantennas,and therefore has great potential for applications such as quantum optics and biosensing.

关键词： dielectric decay radiative

Dynamical properties of water in living cells

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Frontiers of physics 2018年第1期13卷 1-7页

作者： Irina Piazza Antonio Cupane Emmanuel L. Barbier Claire Rome Nora Collomb Jacques Ollivier Miguel A. Gonzalez Francesca Natali Dept. of Physics and Chemistry University of Palermo Viale delle Scienze Ed. 18 90122 Palermo Italy institut Laue-langevin 71 avenue des Martyrs 38042 Grenoble Cedex 9 France institut des Neurosciences Universite Grenoble-Alpes 38044 Grenoble France Inseam U1216 Grenoble France CNR-IOM OGG 6 rue Jules Horowitz 38042 Grenoble Cedex 9 France

With the aim of studying the effect of water dynamics on the properties of biological systems, in this paper, we present a quasi-elastic neutron scattering study on three different types of living cells, differing both in their morphological and tumor properties. The measured scattering signal, which essentially originates from hydrogen atoms present in the investigated systems, has been analyzed using a global fitting strategy using an optimized theoretical model that considers various classes of hydrogen atoms and allows disentangling diffusive and rotational motions. The approach has been carefully validated by checking the reliability of the calculation of parameters and their 99% confidence intervals. We demonstrate that quasi-elastic neutron scattering is a suitable experimental technique to characterize the dynamics of intracellular water in the angstrom/picosecond space/time scale and to investigate the effect of water dynamics on cellular biodiversity.

关键词： quasi-elastic neutron scattering intracellular water water structure and dynamics

Dynamic full-field optical coherence tomography:3D live-imaging of retinal organoids

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Light(Science & Applications) 2020年第1期9卷 665-673页

作者： Jules Scholler Kassandra Groux Olivier Goureau Jose-Alain Sahel Mathias Fink Sacha Reichman Claude Boccara Kate Grieve institut langevin ESPCI ParisPSL UniversityCNRS10 rue VauquelinParisFrance institut de la Vision Sorbonne UniversiteINSERMCNRSF-75012 ParisFrance Quinze-Vingts National Eye Hospital 28 Rue de CharentonParis 75012France Fondation Ophtalmologique Rothschild F-75019 ParisFrance Department of Ophthalmology The University of Pittsburgh School of MedicinePittsburghPA 15213United States

Optical coherence tomography offers astounding opportunities to image the complex structure of living tissue but lacks functional *** present dynamic full-field optical coherence tomography as a technique to noninvasively image living human induced pluripotent stem cell-derived retinal *** images with an endogenous contrast linked to organelle motility are generated,with submicrometre spatial resolution and millisecond temporal resolution,creating a way to identify specific cell types in living tissue via their function.

关键词： optical function image

Synthesis and X-Ray Diffraction Analyses of Calcium Hydroxide Nanoparticles in Aqueous Suspension

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Advances in Materials Physics and Chemistry 2013年第1期3卷 108-112页

作者： G. Taglieri C. Mondelli V. Daniele E. Pusceddu A. Trapananti CNR-IOM-OGG institut Laue langevin Grenoble France CNR-IOM-OGG c/o ESRF Grenoble France institut Laue langevin Grenoble France University of L’Aquila Department of Industrial and Information Engineering and Economics L’Aquila Italy

Calcium hydroxide nanoparticles in aqueous suspensions (also called nanolime) were successfully employed in Cultural Heritage conservation thanks to the ability of favoring readhesion of the pictorial layer on original carbonatic substrates or allowing to a better superficial cohesion and protection of treated stones. In this work, we have synthesized nanolime particles in aqueous suspension by two different methods. The produced particles were characterized in the laboratory, in terms of structural and morphological features, by means of X-Ray diffraction powder (XRD) and by transmission electron microscopy (TEM), respectively. Nanoparticles were crystalline, regularly shaped, hexagonally plated and with side dimensions generally ranging from 300 nm to 30 nm or less. Crystal structure of nanolime particles directly in the aqueous suspension, has been also analyzed by synchrotron diffraction from X-ray synchrotron radiation (SR-XRD);data have been analyzed by means of the Rietveld method and we have investigated the structure of Ca(OH)2 particles in suspension in terms of cell parameters, atomic coordinates, bond lengths and angles.

关键词： Nanoparticles Calcium Hydroxide Crystal Structure X-Ray Diffraction Crystal Morphology

Ni-based catalysts obtained from perovskites oxides for ethanol steam reforming

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燃料化学学报 2018年第11期46卷 1332-1341页

作者： Fabiola Nerina Agüero Jose Antonio Alonso Maria Teresa Fernández-Díaz Luis Eduardo Cadus instituto de Investigaciones en Tecnología Química(INTEQUI) UNSL-CONICETAlmirante Brown 14555700 San LuisArgentina instituto de Ciencia de Materiales de Madrid Consejo Superior de Investigaciones CientíficasCantoblanco28049 MadridSpain institut Laue-langevin B.P.156F-38042 Grenoble Cedex 9France

Perovskites as host structures of cations were used in order to generate in situ active and stable catalysts for ethanol steam reforming. For this purpose,La_(1-x)Mg_xAl_(1-y)Ni_yO_3(x = 0.1; y = 0,0.1,0.2,0.3) perovskites were synthetized by the citrate *** segregation is evident for a substitution level higher than 0. 2. The segregation of Ni as NiO generated species interacts with different metal-support after the reduction step. The y = 0.1 catalyst presents the highest H_2 yield value about 85% during reaction time,with low mean values of CH_4 and CO selectivities of 3.4% and 11%,respectively and a low carbon formation. The better performance of y = 0.1 catalyst could be attributed to the minor proportion of segregated phases,thus a controlled expulsion of Ni is successfully reached.

关键词： perovskites catalyst design ethanol steam reforming