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2019

ILL and ESRF Colloquium

Friday 6 December 2019 at 14.00 in Chadwick Amphitheatre

Prof. Arnaud Desmedt
Groupe Spectroscopie Moléculaire
ISM UMR5255 CNRS
University Bordeaux, France
arnaud.desmedt@remove-this.u-bordeaux.fr

Gas hydrates are ice-like systems made of a network of hydrogen-bonded water molecules (forming host cages) that is stabilized by the presence of foreign guest molecules [1]. The natural existence of large quantities of hydrocarbon hydrates in deep oceans and permafrost is certainly at the origin of numerous applications in areas such as energy, geophysics sciences and innovative technologies [2]. Their hypothetical occurrence in extraterrestrial objects (planets, comets and planetesimal) is also the subject of numerous researches in astrophysics [3]. At a fundamental level, their nanostructuration confers on these materials specific properties (e.g. molecular selectivity, transport properties) for which the host-guest interactions play a key role [4,5]. These interactions occur on a broad timescale and thus require the use of a multi-technique approach (Neutron scattering, Raman, NMR, Classical and ab-initio Molecular Dynamics Simulations). The presentation will review recent results obtained on the physical chemistry of clathrate hydrates towards two main issues - for which neutron scattering brings significant contributions: gas selectivity and structural metastability on one hand, and super-protonic conduction on the other hand.
Recent theoretical works suggest that the nitrogen depletion observed on the Jupiter family comet 67P/Churyumov-Gerasimenko might be due to preferential encapsulation of carbon monoxide with respect to nitrogen inside mixed gas hydrate [6]. The presentation will report the first experimental investigations of such a preferential trapping, together with unusual structural metastability, as revealed by means of Raman scattering, Neutron diffraction and Quantum Mechanics calculations in various mixed gas (CO, CO2, N2) hydrates [7-13].
In addition to gaseous species, clathrate hydrates may encapsulate strong acids. Such supramolecular assembly leads to generate super-protonic conductors (i.e. with protonic conduction of the order of 0.1S/cm) [14]. Quasi-elastic neutron scattering is a unique technique for disentangling the proton transport mechanism involved in such ice-like systems [15,16]. This issue will be reviewed by outlining the contributions of Neutron scattering together with complementary techniques such as ab-initio Molecular Dynamics, Raman imaging or pulsed-field gradient proton NMR. Moreover, new opportunities in the area of energy (electrochemical energy production [17] and hydrogen storage [18-20]) are offered thanks to the strong acidic character of clathrate hydrates. These points will be outlined.

[1] E. D. Sloan and C. A. Koh, Clathrate Hydrates of natural gases, Taylor & Francis-CRC Press, Boca Raton, FL, 3rd edn, 2008.
[2] L. Ruffine, D. Broseta, A. Desmedt, Eds, Gas Hydrates 2: Geoscience Issues and Potential Industrial Applications, Wiley: London (2018).
[3] e.g. G. Tobie et al, Nature 2006, 440, P.61 // Nature 2015, 519, p.162.
[4] D. Broseta, L. Ruffine, A. Desmedt, Eds, Gas hydrates 1: Fundamentals, Characterization and Modeling, Wiley: London (2017)
[5] A. Desmedt, et al. Eur. Phys. J. Special Topics 213 (2012) 103-127
[6] S. Lectez, et al, Astrophys. J. Lett., 2015, 805: L1.
[7] C. Petuya, et al, J. Phys. Chem. C 121(25) (2017) 13798–13802.
[8] C. Petuya, et al, J. Phys. Chem. C 122(1) (2018) 566 –573.
[9] C. Petuya, et al, Crystals 8 (2018) 145(1-13).
[10] C. Petuya, et al, Chem. Comm. 54 (2018) 4290-4293.
[11] C. Petuya, et al, J. Phys. Chem. C 123(8) (2019) 4871-4878.
[12] C. Petuya, et al, J. Chem. Phys. 150(18) (2019) 184705.
[13] C. Métais, et al, in preparation.
[14] J. Cha, et al. J. Phys. Chem. C 2008, 112, 13332−13335.
[15] L. Bedouret, et al, J. Phys. Chem. B 118 (2014) 13357−13364.
[16] A. Desmedt, et al, Solid State Ionics, 252 (2013) 19-25
[17] S. Desplanche et al, article in preparation // A. Desmedt, S. Desplanche et al, Patent FR 18 53886 (2018).
[18] E. Pefoute, et al, J. Phys. Chem. C 116(32) (2012) 16823
[19] A. Desmedt, et al, J. Phys. Chem. C 119 (2015) 8904-8911
[20] T.T. Nguyen, et al, in preparation.

Presentation (pdf - 16.70 Mi)

ILL Colloquium

Thursday 28 November 2019 at 14.00 in Seminar Room ILL 4, 1st floor

Prof. Robert Mc Greevy
Director of ISIS Neutron and Muon Source
Science & Technology Facilities Council
Rutherford Appleton Laboratory
Harwell Campus
Didcot OX11 0QX

2019 is a watershed year for neutrons in Europe, with the closure of three facilities. It is not only timely, but necessary, to take a hard look at the future role of neutrons and our neutron facilities. The success of the past 50 years does not imply relevance for the next 50. How do we ensure capability to address the evolving scientific challenges as well as capacity to support a viable but less expert user community, over an increasingly broad range of science, and all within a finite budget? How do we best distribute that budget across the neutron source(s), the instruments, sample environment and software/data to maximise our impact, and what is the impact we are trying to maximise? How do we address societal concerns such as security or environmental sustainability? Will artificial intelligence help us or is it just a distraction?  
In this colloquium I will take a (hopefully) thought provoking look at these questions – and more.   All opinions expressed will be solely my own and do not represent the views or opinions of my employer!

Presentation (pdf - 6.56 Mi)

ILL - ESRF COLLOQUIUM

Friday 15 november at 14.00 in Chadwick Amphitheatre

Dr. Anders MADSEN
European XFEL
Hamburg, Germany
anders.madsen@remove-this.xfel.eu

The European XFEL (EuXFEL) is the world’s most powerful hard X-ray laser since its inauguration in 2017. In the talk, I will discuss the science goals of the MID station at EuXFEL as well as the beamline design and scientific instrumentation. The design work started in 2011 with first beam received in Dec 2018 and a round of early experiments conducted in 2019. MID focuses on the use of extremely short, intense, and coherent hard X-ray beams that EuXFEL can produce to investigate dynamics processes in materials by imaging and scattering. Results of the commissioning and early science results will be presented. In 2020 the capabilities of the MID station will be further enhanced to include femtosecond optical lasers for pump-probe experiments as well as an X-ray split-delay line for speckle visibility studies of ultrafast dynamics.

Presentation (pdf - 13.19 Mi)

ILL COLLOQUIUM

Friday 8 November at 14.00 in Chadwick Amphitheatre

Dr Yoshie OTAKE
Neutron Beam Technology Team  Team Leader
RIKEN Center for Advanced Photonics (RAP)
2-1 Hirosawa, Wako-shi, Saitama, 315-0198, Japan
Neutron Application Facilities  building
yotake@remove-this.riken.jp

Neutron beam has high penetration power for such metals as iron and steel, aluminum and so on, and high sensitivities for such light elements as hydrogen, boron, lithium, while it interacts with nucleus. Until now, neutron beam can only be used at such large facilities as SNS in US, J-PARC in Japan, ILL in France, and so on. Now strong requests for the non-destructive quantitative analysis on-site for such bulk samples as iron deformed plate with some mm thickness, and for the development of Nano-materials in the universities, companies are increasing.

RIKEN Accelerator-driven compact neutron source, RANS, has been operated since 2013[1], with 7MeV proton with beryllium target.

There are two major goals of RANS research and development. One is to establish a popular compact neutron system of floor-standing type for industrial use as a non-destructive analysis equipment. Another goal is to invent a novel transportable compact neutron system for the preventive maintenance of large scale construction such as a bridge.

There are more than six kinds of instruments, and neutron measurements are available with RANS. The low energy transmission imaging, neutron diffractometer [2], small angle scattering instruments, fast neutron transmission imaging [3], fast neutron reflected imaging [4], neutron induced prompt gamma-ray analysis and neutron activation analysis are available with RANS. As an example of the results, neutron diffraction technique for the measurement of retained austenite volume fraction has been newly developed by using RANS, which allows us to perform the "on-site" measurement with the accuracy of 1%. Retained austenite is one of the key factors that dominate the mechanical properties of an advanced high strength steel sheet. Neutron beam has an important advantage in its large penetration depth which enables the measurement of bulk-average quantities. The developed measurement technique has a possibility to utilize the above advantages of neutron beam by installing the compact neutron source in laboratories.

For further compact neutron system, RANS-II with 2.49 MeV proton linac starts generating neutron. The neutron applications with RANS will be discussed in detail.

[reference]

[1] Y.Otake, "A Compact Proton Linac Neutron Source at RIKEN", “Applications of Laser-Driven Particle Acceleration” eds. Paul Bolton, et al. (2018) Chapter 19 pp.291-314 CRC Press
[2] Y. Ikeda, et al. "Prospect for application of compact accelerator-based neutron source to neutron engineering diffraction", Nucl. Instr. Meth. An 833(2016) pp 61-67
[3] Y. Seki et al. “Fast neutron transmission imaging of the interior of large-scale concrete structures using a newly developed pixel-type detector", Nucl Inst. Methods Phys Res A 870 (2017) pp. 148-155
[4] Y. Ikeda, et al. "Nondestructive measurement for water and voids in concrete with compact neutron source", Plasma and Fusion Research Vol.13(2018) pp.2406005-1-5
 

ILL Colloquium: MLZ – present status and vision 2030

Friday 20 September at 14.00 in Chadwick Aphitheatre

Prof. Dr. Peter Müller-Buschbaum 1,2
1 Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien,
James-Franck-Str. 1, 85748 Garching, Germany
2 Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München,
Lichtenbergstr. 1, 85748 Garching, Germany
E-mail: muellerb@remove-this.ph.tum.de

The Heinz Maier-Leibnitz Zentrum (MLZ) is a leading center for cutting-edge research with neutrons and positrons, offering a unique suite of high-performance neutron scattering instruments. The MLZ represents the cooperation between the Technische Universität München (TUM) and three research centres of the Helmholtz Association, namely Forschungszentrum Jülich, Helmholtz-Zentrum Geesthacht (HZG) and the Helmholtz-Zentrum Berlin (HZB, inactive partner) to exploit the scientific use of the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) in Garching near Munich. The MLZ relies on a network of strong partners such as the FRM II, the Jülich Centre for Neutron Science (JCNS), the German Engineering Materials Science Centre (GEMS) at HZG as well as 10 different German universities and institutes of the Max-Planck-Society.
The present status of MLZ and future vision 2030 will be presented. Our recently formulated road map identifies the main scientific drivers for research at MLZ, the present status for the key scientific areas, and the consequential science driven development of instrumentation and services offered to the users.
With selected scientific highlights, the possibilities of neutron-based research will be briefly illustrated.

ILL Colloquium: Scientific Babel: English, German, and the Fall of Polyglot Natural Science.

Friday 12 July at 14.00 a.m. in Chadwick Amphitheatre

Prof. Michael D Gordin
Rosengarten Professor of Modern and Contemporary History
Director, Society of Fellows in the Liberal Arts
Princeton University, USA
www.michaelgordin.com

Abstract

Communication, especially publication, in the natural sciences today takes place almost exclusively in English. This phenomenon is relatively recent, with a strong shift toward monoglot natural science taking place roughly half a century ago. This talk offers an account of the transformation of communication in the natural sciences from a primarily trilingual situation in 1850 (English, French, and German) to a bilingual situation after the Second World War (English primary, Russian secondary), to the monoglot system of today. In particular, the significant and sudden decline of German, due to political upheaval during the twentieth century (especially the First World War) and cultural processes within the scientific community, was the primary condition for the transformation of a polyglot linguistic system in the natural sciences to a monoglot one.

ILL and ESRF Colloquium: Bionic Hearing: The Science and the Experience

Tuesday 4 June at 11.00 am in Chadwick Amphitheatre

Prof. Ian Shipsey
Henry Moseley Centenary Professor of Physics
Head, Department of Physics
University of Oxford

ian.shipsey@physics.ox.ac.uk

Abstract

Cochlear implants are the first device to successfully restore neural function.  They have instigated a popular but controversial revolution in the treatment of deafness, and they serve as a model for research in neuroscience and biomedical engineering.  After a visual tour of the physiology of natural hearing the function of cochlear implants will be described in the context of electrical engineering, psychophysics, clinical evaluation, and my own personal experience.  
The audience will have the opportunity to experience speech and music heard through a cochlear implant. The social implications of cochlear implantation and the future outlook for auditory prostheses will also be discussed.

About the speaker:
Ian Shipsey is a particle physicist, and a Professor of Physics at Oxford University.  He has been profoundly deaf since 1989. In 2002 he heard the voice of his daughter for the first time, and his wife's voice for the first time in thirteen years thanks to a cochlear implant.

The presentation will be at the level of Scientific American.

Presentation (pdf - 4.13 Mi)

ILL – ESRF Colloquium: Spatial and Temporal CryoEM of Soft Molecular Assemblies and other Colloids

Friday 8 February at 2.00 pm in Chadwick Amphitheatre, ILL 4

Prof Dganit Danino
Biotechnology and Food engineering and the Russell Berrie Nanotechnology Institute,
Technion-Israel Institute of Technology,
Haifa, 32000,  Israel.
email CryoEM@Technion.ac.il

“The Nobel Prize in Chemistry 2017 was awarded for the development of cryoelectron microscopy, which both simplifies and improves the imaging of Biomolecules".

For nearly 20 years we use this powerful tool to unfold structure-function property relations of molecular assemblies, soft nanostructures and colloids, of natural and synthetic building blocks. Our work focuses on resolving complex structures and dynamic processes, using the unique ability of cryo-EM to simultaneously disclose coexisting structures, capture infrequent and short-lived intermediates, and directly illuminate fine structural details at ~1nm resolution, all at the hydrated state. Recent cutting edge improvements e.g., in detection by direct detectors, in optics through phase plates and in software, provide higher resolution, clearer and more precise structural, spatial, temporal and quantitative data.
We will discuss past, current and prospect application of cryo-EM to soft materials and colloids [1]. Specific examples will include complete analysis of micellar systems [2] including first presentation of their spatial organization achieved through cryo-electron tomography (CryoET), time-resolution investigations e.g., of 1-dimensional ribbons and nanotubes [3], lipid-nanoparticles and lipid-nucleic acid structures [4-6], and protein-membrane complexes. In line with the research in the EPN campus, we will emphasize the synergy between CryoEM and scattering, as well as the strength in combining morphological and high-resolution CryoEM for resolving biological and nanomedical questions.

References :
[1] Danino, Curr Opin Colloid In (2012) 17, 316–329;
[2] Danino et al., J Phys Chem Lett (2016) 7, 1434–1439;
[3] Danino and Egelman, Curr Opin Colloid In (2018) 34, 100-113;
[4] Michel et al., Angew Chem (2014) 3, 12441-12445;
[5] Dahlman et al., Nature Nanotechnology (2014) 9, 648-655;
[6] Dong et al., Nano Letters (2016) 16, 842-848;

Presentation (pdf - 34 Mi)