Plasmons in Liquid Metals Studied by Inelastic X-ray Scattering

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Koji Kimura ◽  
Toru Hagiya ◽  
Kazuhiro Matsuda ◽  
Nozomu Hiraoka

AbstractPlasmon is a collective excitation of electrons in materials. Since plasmon can be observed in a wide range of the phase diagram including the solid, liquid, and classical plasma phases, the investigation of the electronic states through the plasmon is of great significance in order to obtain a unified insight into the electronic states in various phases of matter. Inelastic X-ray scattering (IXS) is an ideal tool for such an investigation, because it can be applied to the samples in the liquid state and those in an extreme conditions. In this review, we discuss IXS results on the plasmons in liquid metals, and also describe a formulation to predict the plasmon energy and the lifetime in liquid metals. The formulation takes into account the effect of the ionic structure within the nearly free electron approximation, and reproduces well the experimental results.

Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 730
Author(s):  
Erik Sarnello ◽  
Tao Li

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.


2019 ◽  
Vol 92 ◽  
pp. 01005
Author(s):  
Georgios Birmpilis ◽  
Reza Ahmadi-Naghadeh ◽  
Jelke Dijkstra

X-ray scattering is a promising non-invasive technique to study evolving nano- and micromechanics in clays. This study discusses the experimental considerations and a successful method to enable X-ray scattering to study clay samples at two extreme stages of consolidation. It is shown that the proposed sample environment comprising flat capillaries with a hydrophobic coating can be used for a wide range of voids ratios ranging from a clay suspension to consolidated clay samples, that are cut from larger specimens of reconstituted or natural clay. The initial X-ray scattering results using a laboratory instrument indicate that valuable information on, in principal evolving, clay fabric can be measured. Features such as characteristic distance between structural units and particle orientations are obtained for a slurry and a consolidated sample of kaolinite. Combined with other promising measurement techniques from Materials Science the proposed method will help advance the contemporary understanding on the behaviour of dense colloidal systems of clay, as it does not require detrimental sample preparation


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Christoph Eckart Schrank ◽  
Oliver Gaede ◽  
Tomasz Blach ◽  
Katherine Carmen Michelle Gioseffi ◽  
Stephen Mudie ◽  
...  

AbstractThe dehydration of gypsum to hemihydrate has been studied for decades because it is an important model reaction for understanding fluid-triggered earthquakes, and due to the global use of plaster of Paris in the construction industry. The dehydration kinetics of gypsum strongly depend on temperature and water vapour pressure. Here, we perform fast, time-resolved synchrotron X-ray scattering on natural alabaster samples, finding that a small elastic load accelerates the dehydration reaction significantly. The mechanical acceleration of the reaction consumes about 10,000 times less energy than that due to heating. We propose that this thermodynamically surprising finding is caused by geometry-energy interactions in the microstructure, which facilitate nucleation and growth of the new crystalline phase. Our results open research avenues on the fundamental thermo-mechanics of crystal hydrates and the interaction of stress and chemical reactions in crystalline solids with a wide range of implications, from understanding dehydration-triggered earthquakes to the energy-efficient design of calcination processes.


2013 ◽  
Vol 46 (5) ◽  
pp. 1508-1512 ◽  
Author(s):  
Byron Freelon ◽  
Kamlesh Suthar ◽  
Jan Ilavsky

Coupling small-angle X-ray scattering (SAXS) and ultra-small-angle X-ray scattering (USAXS) provides a powerful system of techniques for determining the structural organization of nanostructured materials that exhibit a wide range of characteristic length scales. A new facility that combines high-energy (HE) SAXS and USAXS has been developed at the Advanced Photon Source (APS). The application of X-rays across a range of energies, from 10 to 50 keV, offers opportunities to probe structural behavior at the nano- and microscale. An X-ray setup that can characterize both soft matter or hard matter and high-Zsamples in the solid or solution forms is described. Recent upgrades to the Sector 15ID beamline allow an extension of the X-ray energy range and improved beam intensity. The function and performance of the dedicated USAXS/HE-SAXS ChemMatCARS-APS facility is described.


2018 ◽  
Vol 51 (3) ◽  
pp. 867-882 ◽  
Author(s):  
Jan Ilavsky ◽  
Fan Zhang ◽  
Ross N. Andrews ◽  
Ivan Kuzmenko ◽  
Pete R. Jemian ◽  
...  

Following many years of evolutionary development, first at the National Synchrotron Light Source, Brookhaven National Laboratory, and then at the Advanced Photon Source (APS), Argonne National Laboratory, the APS ultra-small-angle X-ray scattering (USAXS) facility has been transformed by several new developments. These comprise a conversion to higher-order crystal optics and higher X-ray energies as the standard operating mode, rapid fly scan measurements also as a standard operational mode, automated contiguous pinhole small-angle X-ray scattering (SAXS) measurements at intermediate scattering vectors, and associated rapid wide-angle X-ray scattering (WAXS) measurements for X-ray diffraction without disturbing the sample geometry. With each mode using the USAXS incident beam optics upstream of the sample, USAXS/SAXS/WAXS measurements can now be made within 5 min, allowingin situandoperandomeasurement capabilities with great flexibility under a wide range of sample conditions. These developments are described, together with examples of their application to investigate materials phenomena of technological importance. Developments of two novel USAXS applications, USAXS-based X-ray photon correlation spectroscopy and USAXS imaging, are also briefly reviewed.


Author(s):  
Jonathan Almer

Acquisition of microstructural information during realistic service conditions is an ongoing need for fundamental materials insight and computational input. In addition, for engineering applications it is often important to be able to study materials over a wide range of penetration depths, from the surface to bulk. In this presentation we discuss developments at the Sector 1-ID beamline of the Advanced Photon Source (APS) to utilize high-energy x-ray scattering for such studies. The use of high-energies (~80 keV) provides a highly penetrating probe, with sampling depths up to several mm in most materials. Through the development and use of high-energy optics, we can perform both small- and wide-angle scattering (SAXS/WAXS), to probe a large range of sample dimensions in reciprocal space (ranging from Angstroms to hundreds of nanometers), with real space resolutions ranging from microns to mm.


2020 ◽  
Vol 48 (14) ◽  
pp. 8090-8098
Author(s):  
Thomas Zettl ◽  
Xuesong Shi ◽  
Steve Bonilla ◽  
Steffen M Sedlak ◽  
Jan Lipfert ◽  
...  

Abstract The DNA four-way (Holliday) junction is the central intermediate of genetic recombination, yet key aspects of its conformational and thermodynamic properties remain unclear. While multiple experimental approaches have been used to characterize the canonical X-shape conformers under specific ionic conditions, the complete conformational ensemble of this motif, especially at low ionic conditions, remains largely undetermined. In line with previous studies, our single-molecule Förster resonance energy transfer (smFRET) measurements of junction dynamics revealed transitions between two states under high salt conditions, but smFRET could not determine whether there are fast and unresolvable transitions between distinct conformations or a broad ensemble of related states under low and intermediate salt conditions. We therefore used an emerging technique, X-ray scattering interferometry (XSI), to directly probe the conformational ensemble of the Holliday junction across a wide range of ionic conditions. Our results demonstrated that the four-way junction adopts an out-of-plane geometry under low ionic conditions and revealed a conformational state at intermediate ionic conditions previously undetected by other methods. Our results provide critical information to build toward a full description of the conformational landscape of the Holliday junction and underscore the utility of XSI for probing conformational ensembles under a wide range of solution conditions.


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