Optimizing the geometry of aerodynamic lens injectors for single-particle coherent diffractive imaging of gold nanoparticles

Single-particle X-ray diffractive imaging (SPI) of small (bio-)nanoparticles (NPs) requires optimized injectors to collect sufficient diffraction patterns to allow for the reconstruction of the NP structure with high resolution. Typically, aerodynamic lens-stack injectors are used for NP injection. However, current injectors were developed for larger NPs (>100 nm), and their ability to generate high-density NP beams suffers with decreasing NP size. Here, an aerodynamic lens-stack injector with variable geometry and a geometry-optimization procedure are presented. The optimization for 50 nm gold-NP (AuNP) injection using a numerical-simulation infrastructure capable of calculating the carrier-gas flow and the particle trajectories through the injector is also introduced. The simulations were experimentally validated using spherical AuNPs and sucrose NPs. In addition, the optimized injector was compared with the standard-installation `Uppsala injector' for AuNPs. Results for these heavy particles showed a shift in the particle-beam focus position rather than a change in beam size, which results in a lower gas background for the optimized injector. Optimized aerodynamic lens-stack injectors will allow one to increase NP beam density, reduce the gas background, discover the limits of current injectors and contribute to structure determination of small NPs using SPI.

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Hard X-ray polarizer to enable simultaneous three-dimensional nanoscale imaging of magnetic structure and lattice strain

Journal of Synchrotron Radiation ◽

10.1107/s1600577516009632 ◽

2016 ◽

Vol 23 (5) ◽

pp. 1210-1215 ◽

Cited By ~ 3

Author(s):

Jonathan Logan ◽

Ross Harder ◽

Luxi Li ◽

Daniel Haskel ◽

Pice Chen ◽

...

Keyword(s):

Magnetic Circular Dichroism ◽

Three Dimensional ◽

Control Sample ◽

Magnetic Ordering ◽

X Rays ◽

Diffractive Imaging ◽

X Ray ◽

Coherent Diffractive Imaging ◽

Diffraction Patterns ◽

A New Technique

Recent progress in the development of dichroic Bragg coherent diffractive imaging, a new technique for simultaneous three-dimensional imaging of strain and magnetization at the nanoscale, is reported. This progress includes the installation of a diamond X-ray phase retarder at beamline 34-ID-C of the Advanced Photon Source. The performance of the phase retarder for tuning X-ray polarization is demonstrated with temperature-dependent X-ray magnetic circular dichroism measurements on a gadolinium foil in transmission and on a Gd5Si2Ge2crystal in diffraction geometry with a partially coherent, focused X-ray beam. Feasibility tests for dichroic Bragg coherent diffractive imaging are presented. These tests include (1) using conventional Bragg coherent diffractive imaging to determine whether the phase retarder introduces aberrations using a nonmagnetic gold nanocrystal as a control sample, and (2) collecting coherent diffraction patterns of a magnetic Gd5Si2Ge2nanocrystal with left- and right-circularly polarized X-rays. Future applications of dichroic Bragg coherent diffractive imaging for the correlation of strain and lattice defects with magnetic ordering and inhomogeneities are considered.

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Single-particle coherent diffractive imaging with a soft x-ray free electron laser: towards soot aerosol morphology

Journal of Physics B Atomic Molecular and Optical Physics ◽

10.1088/0953-4075/43/19/194013 ◽

2010 ◽

Vol 43 (19) ◽

pp. 194013 ◽

Cited By ~ 26

Author(s):

Michael J Bogan ◽

Dmitri Starodub ◽

Christina Y Hampton ◽

Raymond G Sierra

Keyword(s):

Single Particle ◽

Free Electron ◽

Free Electron Laser ◽

Diffractive Imaging ◽

X Ray ◽

Coherent Diffractive Imaging ◽

Soot Aerosol

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Study on CO2 Adsorption on LiOH-Modified Al2O3

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.342 ◽

2013 ◽

Vol 284-287 ◽

pp. 342-346 ◽

Cited By ~ 5

Author(s):

Young Min Cho ◽

Young Min Yang ◽

Duck Shin Park ◽

Soon Bark Kwon ◽

Woo Sung Jung ◽

...

Keyword(s):

Flow Rate ◽

Gas Flow ◽

Gas Flow Rate ◽

Carrier Gas ◽

Adsorption Performance ◽

Contact Points ◽

Zeolite 5A ◽

Inflow Condition ◽

Diffraction Patterns ◽

Carrier Gas Flow

LiOH is known to be one of the most efficient CO2adsorbent because it reacts with CO2to form Li2CO3. However, LiOH still suffers from lack of enough hardness for practical use. In this study, various substrates, were modified with LiOH. Their X-ray diffraction patterns were investigated, and LiOH peak was observed from all prepared samples. CO2adsorption capacity of each prepared sample was measured by monitoring CO2concentration change during the adsorption process under constant CO2gas inflow condition. LiOH-modified Al2O3and zeolite 5A showed good CO2adsorption performance, while LiOH-modified AC and SiO2showed relatively poor CO2adsorption. Al2O3and zeolite 5A contains many basic functional groups of Al3+, which promote the neutralization reaction with acidic CO2. The effect of carrier gas, carrier gas flow rate, initial CO2concentration, and amount of LiOH-modified Al2O3loading was investigated. CO2 adsorption performance was better when the carrier gas was N2, because O2competes with CO2on LiOH. CO2adsorption performance was better with lower carrier gas flow rate, lower initial CO2concentration, and less loading of adsorbent due to the increase of contact time and contact points.

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A Monte Carlo ray-tracing simulation of coherent X-ray diffractive imaging

Journal of Synchrotron Radiation ◽

10.1107/s1600577519014425 ◽

2020 ◽

Vol 27 (1) ◽

pp. 134-145 ◽

Cited By ~ 1

Author(s):

Giovanni Fevola ◽

Erik Bergbäck Knudsen ◽

Tiago Ramos ◽

Dina Carbone ◽

Jens Wenzel Andreasen

Keyword(s):

Ray Tracing ◽

Phase Retrieval ◽

Computational Effort ◽

Retrieval Algorithm ◽

Theoretical Formulation ◽

Thin Sample ◽

Diffractive Imaging ◽

X Ray ◽

Coherent Diffractive Imaging ◽

Diffraction Patterns

Coherent diffractive imaging (CDI) experiments are adequately simulated assuming the thin sample approximation and using a Fresnel or Fraunhofer wavefront propagator to obtain the diffraction pattern. Although this method is used in wave-based or hybrid X-ray simulators, here the applicability and effectiveness of an alternative approach that is based solely on ray tracing of Huygens wavelets are investigated. It is shown that diffraction fringes of a grating-like source are accurately predicted and that diffraction patterns of a ptychography dataset from an experiment with realistic parameters can be sampled well enough to be retrieved by a standard phase-retrieval algorithm. Potentials and limits of this approach are highlighted. It is suggested that it could be applied to study imperfect or non-standard CDI configurations lacking a satisfactory theoretical formulation. The considerable computational effort required by this method is justified by the great flexibility provided for easy simulation of a large-parameter space.

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3D Bragg coherent diffractive imaging of five-fold multiply twinned gold nanoparticle

Nanoscale ◽

10.1039/c7nr05028c ◽

2017 ◽

Vol 9 (35) ◽

pp. 13153-13158 ◽

Cited By ~ 6

Author(s):

Jong Woo Kim ◽

Andrew Ulvestad ◽

Sohini Manna ◽

Ross Harder ◽

Eric E. Fullerton ◽

...

Keyword(s):

Gold Nanoparticle ◽

Formation Mechanism ◽

Diffractive Imaging ◽

Coherent Diffractive Imaging

The formation mechanism of five-fold multiply twinned nanoparticles has been a long-term topic because of their geometrical incompatibility.

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On factors affecting surface free energy of carbon black for reinforcing rubber

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0015 ◽

2020 ◽

Vol 9 (1) ◽

pp. 170-181 ◽

Cited By ~ 2

Author(s):

Shangyong Zhang ◽

Ruipeng Zhong ◽

Ruoyu Hong ◽

David Hui

Keyword(s):

Free Energy ◽

Carbon Black ◽

Surface Free Energy ◽

Surface Activity ◽

Gas Flow ◽

Influential Factors ◽

Chromatographic Column ◽

Factors Affecting ◽

Carrier Gas Flow

AbstractThe surface activity of carbon black (CB) is an important factor affecting the reinforcement of rubber. The quantitative determination of the surface activity (surface free energy) of CB is of great significance. A simplified formula is obtained to determine the free energy of CB surface through theoretical analysis and mathematical derivation. The surface free energy for four kinds of industrial CBs were measured by inverse gas chromatography, and the influential factors were studied. The results showed that the aging time of the chromatographic column plays an important role in accurate measurement of the surface free energy of CB, in comparison with the influences from the inlet pressure and carrier gas flow rate of the chromatographic column filled with CB. Several kinds of industrial CB were treated at high temperature, and the surface free energy of CB had a significant increase. With the increase of surface free energy, the maximum torque was decreased significantly, the elongation at break tended to increase, the heat generation of vulcanizates was increased, and the wear resistance was decreased.

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An encryption–decryption framework to validating single-particle imaging

Scientific Reports ◽

10.1038/s41598-020-79589-0 ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Zhou Shen ◽

Colin Zhi Wei Teo ◽

Kartik Ayyer ◽

N. Duane Loh

Keyword(s):

Conceptual Framework ◽

Single Particle ◽

Latent Variables ◽

Ground Truth ◽

Resolving Power ◽

Validation Measure ◽

Encryption Decryption ◽

Diffraction Patterns ◽

Particle Imaging ◽

Single Particle Imaging

AbstractWe propose an encryption–decryption framework for validating diffraction intensity volumes reconstructed using single-particle imaging (SPI) with X-ray free-electron lasers (XFELs) when the ground truth volume is absent. This conceptual framework exploits each reconstructed volumes’ ability to decipher latent variables (e.g. orientations) of unseen sentinel diffraction patterns. Using this framework, we quantify novel measures of orientation disconcurrence, inconsistency, and disagreement between the decryptions by two independently reconstructed volumes. We also study how these measures can be used to define data sufficiency and its relation to spatial resolution, and the practical consequences of focusing XFEL pulses to smaller foci. This conceptual framework overcomes critical ambiguities in using Fourier Shell Correlation (FSC) as a validation measure for SPI. Finally, we show how this encryption-decryption framework naturally leads to an information-theoretic reformulation of the resolving power of XFEL-SPI, which we hope will lead to principled frameworks for experiment and instrument design.

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