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1.
Proc Natl Acad Sci U S A ; 119(29): e2203199119, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858350

RESUMO

Lithium-ion battery (LIB) is a broadly adopted technology for energy storage. With increasing demands to improve the rate capability, cyclability, energy density, safety, and cost efficiency, it is crucial to establish an in-depth understanding of the detailed structural evolution and cell-degradation mechanisms during battery operation. Here, we present a laboratory-based high-resolution and high-throughput X-ray micro-computed laminography approach, which is capable of in situ visualizing of an industry-relevant lithium-ion (Li-ion) pouch cell with superior detection fidelity, resolution, and reliability. This technique enables imaging of the pouch cell at a spatial resolution of 0.5 µm in a laboratory system and permits the identification of submicron features within cathode and anode electrodes. We also demonstrate direct visualization of the lithium plating in the imaged pouch cell, which is an important phenomenon relevant to battery fast charging and low-temperature cycling. Our development presents an avenue toward a thorough understanding of the correlation among multiscale structures, chemomechanical degradation, and electrochemical behavior of industry-scale battery pouch cells.

2.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34140413

RESUMO

Multicontrast X-ray imaging with high resolution and sensitivity using Talbot-Lau interferometry (TLI) offers unique imaging capabilities that are important to a wide range of applications, including the study of morphological features with different physical properties in biological specimens. The conventional X-ray TLI approach relies on an absorption grating to create an array of micrometer-sized X-ray sources, posing numerous limitations, including technical challenges associated with grating fabrication for high-energy operations. We overcome these limitations by developing a TLI system with a microarray anode-structured target (MAAST) source. The MAAST features an array of precisely controlled microstructured metal inserts embedded in a diamond substrate. Using this TLI system, tomography of a Drum fish tooth with high resolution and tri-contrast (absorption, phase, and scattering) reveals useful complementary structural information that is inaccessible otherwise. The results highlight the exceptional capability of high-resolution multicontrast X-ray tomography empowered by the MAAST-based TLI method in biomedical applications.


Assuntos
Tomografia Computadorizada por Raios X , Animais , Análise de Dados , Eletrodos , Peixes/anatomia & histologia , Imageamento Tridimensional , Interferometria , Iluminação , Dente/anatomia & histologia , Dente/diagnóstico por imagem
3.
Chem Commun (Camb) ; 55(8): 1052-1055, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30608504

RESUMO

Biological X-ray fluorescence microscopy (XFM) is an important tool for determining quantitative distributions of bioinorganics and essential trace elements. Here we present a new analysis approach for rapid nanoscale ptychographic imaging and simultaneous chemical mapping of large radiation sensitive specimens without image degradation associated with probe evolution.

4.
Sci Rep ; 7(1): 445, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28348401

RESUMO

X-ray microscopy can be used to image whole, unsectioned cells in their native hydrated state. It complements the higher resolution of electron microscopy for submicrometer thick specimens, and the molecule-specific imaging capabilites of fluorescence light microscopy. We describe here the first use of fast, continuous x-ray scanning of frozen hydrated cells for simultaneous sub-20 nm resolution ptychographic transmission imaging with high contrast, and sub-100 nm resolution deconvolved x-ray fluorescence imaging of diffusible and bound ions at native concentrations, without the need to add specific labels. By working with cells that have been rapidly frozen without the use of chemical fixatives, and imaging them under cryogenic conditions, we are able to obtain images with well preserved structural and chemical composition, and sufficient stability against radiation damage to allow for multiple images to be obtained with no observable change.


Assuntos
Congelamento , Processamento de Imagem Assistida por Computador , Microscopia de Fluorescência/métodos , Água/química , Chlamydomonas/citologia , Raios X
5.
J Synchrotron Radiat ; 23(Pt 5): 1151-7, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27577770

RESUMO

Owing to its extreme sensitivity, quantitative mapping of elemental distributions via X-ray fluorescence microscopy (XFM) has become a key microanalytical technique. The recent realisation of scanning X-ray diffraction microscopy (SXDM) meanwhile provides an avenue for quantitative super-resolved ultra-structural visualization. The similarity of their experimental geometries indicates excellent prospects for simultaneous acquisition. Here, in both step- and fly-scanning modes, robust, simultaneous XFM-SXDM is demonstrated.

6.
Opt Express ; 23(5): 5438-51, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836777

RESUMO

Ptychography is a coherent diffraction imaging (CDI) method for extended objects in which diffraction patterns are acquired sequentially from overlapping coherent illumination spots. The object's complex transmission function can be reconstructed from those diffraction patterns at a spatial resolution limited only by the scattering strength of the object and the detector geometry. Most experiments to date have positioned the illumination spots on the sample using a move-settle-measure sequence in which the move and settle steps can take longer to complete than the measure step. We describe here the use of a continuous "fly-scan" mode for ptychographic data collection in which the sample is moved continuously, so that the experiment resembles one of integrating the diffraction patterns from multiple probe positions. This allows one to use multiple probe mode reconstruction methods to obtain an image of the object and also of the illumination function. We show in simulations, and in x-ray imaging experiments, some of the characteristics of fly-scan ptychography, including a factor of 25 reduction in the data acquisition time. This approach will become increasingly important as brighter x-ray sources are developed, such as diffraction limited storage rings.


Assuntos
Imageamento Tridimensional , Movimento (Física) , Raios X , Animais , Simulação por Computador
7.
Proc Natl Acad Sci U S A ; 112(8): 2314-9, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25675478

RESUMO

Trace metals play important roles in normal and in disease-causing biological functions. X-ray fluorescence microscopy reveals trace elements with no dependence on binding affinities (unlike with visible light fluorophores) and with improved sensitivity relative to electron probes. However, X-ray fluorescence is not very sensitive for showing the light elements that comprise the majority of cellular material. Here we show that X-ray ptychography can be combined with fluorescence to image both cellular structure and trace element distribution in frozen-hydrated cells at cryogenic temperatures, with high structural and chemical fidelity. Ptychographic reconstruction algorithms deliver phase and absorption contrast images at a resolution beyond that of the illuminating lens or beam size. Using 5.2-keV X-rays, we have obtained sub-30-nm resolution structural images and ∼90-nm-resolution fluorescence images of several elements in frozen-hydrated green algae. This combined approach offers a way to study the role of trace elements in their structural context.


Assuntos
Clorófitas/anatomia & histologia , Congelamento , Imageamento Tridimensional/métodos , Difração de Raios X/métodos , Clorófitas/citologia , Microscopia de Fluorescência
8.
Proc SPIE Int Soc Opt Eng ; 95922015 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27041790

RESUMO

X-ray fluorescence offers unparalleled sensitivity for imaging the nanoscale distribution of trace elements in micrometer thick samples, while x-ray ptychography offers an approach to image light element containing structures at a resolution beyond that of the x-ray lens used. These methods can be used in combination, and in continuous scan mode for rapid data acquisition when using multiple probe mode reconstruction methods. We discuss here the opportunities and limitations of making use of additional information provided by ptychography to improve x-ray fluorescence images in two ways: by using position-error-correction algorithms to correct for scan distortions in fluorescence scans, and by considering the signal-to-noise limits on previously-demonstrated ptychographic probe deconvolution methods. This highlights the advantages of using a combined approach.

9.
J Synchrotron Radiat ; 21(Pt 6): 1224-30, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25343788

RESUMO

Data Exchange is a simple data model designed to interface, or `exchange', data among different instruments, and to enable sharing of data analysis tools. Data Exchange focuses on technique rather than instrument descriptions, and on provenance tracking of analysis steps and results. In this paper the successful application of the Data Exchange model to a variety of X-ray techniques, including tomography, fluorescence spectroscopy, fluorescence tomography and photon correlation spectroscopy, is described.

10.
Ultramicroscopy ; 143: 88-92, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24209602

RESUMO

Phase-diverse X-ray coherent diffractive imaging (CDI) provides a route to high sensitivity and spatial resolution with moderate radiation dose. It also provides a robust solution to the well-known phase-problem, making on-line image reconstruction feasible. Here we apply phase-diverse CDI to a cellular sample, obtaining images of an erythrocyte infected by the sexual stage of the malaria parasite, Plasmodium falciparum, with a radiation dose significantly lower than the lowest dose previously reported for cellular imaging using CDI. The high sensitivity and resolution allow key biological features to be identified within intact cells, providing complementary information to optical and electron microscopy. This high throughput method could be used for fast tomographic imaging, or to generate multiple replicates in two-dimensions of hydrated biological systems without freezing or fixing. This work demonstrates that phase-diverse CDI is a valuable complementary imaging method for the biological sciences and ready for immediate application.


Assuntos
Diagnóstico por Imagem/métodos , Malária Falciparum/diagnóstico , Parasitos/ultraestrutura , Plasmodium falciparum/ultraestrutura , Difração de Raios X/métodos , Animais , Eritrócitos/parasitologia , Processamento de Imagem Assistida por Computador/métodos , Microscopia Eletrônica/métodos , Imagem Óptica/métodos , Sensibilidade e Especificidade
11.
Opt Express ; 22(26): 32082-97, 2014 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-25607174

RESUMO

Ptychography is an imaging method whereby a coherent beam is scanned across an object, and an image is obtained by iterative phasing of the set of diffraction patterns. It is able to be used to image extended objects at a resolution limited by scattering strength of the object and detector geometry, rather than at an optics-imposed limit. As technical advances allow larger fields to be imaged, computational challenges arise for reconstructing the correspondingly larger data volumes, yet at the same time there is also a need to deliver reconstructed images immediately so that one can evaluate the next steps to take in an experiment. Here we present a parallel method for real-time ptychographic phase retrieval. It uses a hybrid parallel strategy to divide the computation between multiple graphics processing units (GPUs) and then employs novel techniques to merge sub-datasets into a single complex phase and amplitude image. Results are shown on a simulated specimen and a real dataset from an X-ray experiment conducted at a synchrotron light source.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Microscopia/métodos , Refratometria/métodos , Processamento de Sinais Assistido por Computador , Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Microscopia/instrumentação , Refratometria/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Sci Rep ; 3: 2288, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23887204

RESUMO

X-ray tomography can provide structural information of whole cells in close to their native state. Radiation-induced damage, however, imposes a practical limit to image resolution, and as such, a choice between damage, image contrast, and image resolution must be made. New coherent diffractive imaging techniques, such Fresnel Coherent Diffractive Imaging (FCDI), allows quantitative phase information with exceptional dose efficiency, high contrast, and nano-scale resolution. Here we present three-dimensional quantitative images of a whole eukaryotic cell by FCDI at a spatial resolution below 70 nm with sufficient phase contrast to distinguish major cellular components. From our data, we estimate that the minimum dose required for a similar resolution is close to that predicted by the Rose criterion, considerably below accepted estimates of the maximum dose a frozen-hydrated cell can tolerate. Based on the dose efficiency, contrast, and resolution achieved, we expect this technique will find immediate applications in tomographic cellular characterisation.


Assuntos
Análise de Célula Única/métodos , Tomografia Computadorizada por Raios X/métodos , Eritrócitos/citologia , Eritrócitos/parasitologia , Humanos
13.
Opt Express ; 20(21): 24038-48, 2012 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-23188371

RESUMO

A scanning coherent diffraction imaging method was used to reconstruct the X-ray wavefronts produced by a Fresnel zone plate (FZP) and by Kirkpatrick-Baez (KB) focusing mirrors. The ptychographical measurement was conducted repeatedly by placing a lithographed test sample at different defocused planes. The wavefronts, recovered by phase-retrieval at well-separated planes, show good consistency with numerical propagation results, which provides a self-verification. The validity of the obtained FZP wavefront was further confirmed with theoretical predictions.


Assuntos
Lentes , Refratometria/instrumentação , Raios X , Desenho de Equipamento , Análise de Falha de Equipamento
14.
Ultramicroscopy ; 111(8): 1184-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21762656

RESUMO

This paper demonstrates the application of the high sensitivity, low radiation dose imaging method recently presented as phase diverse coherent diffraction imaging, to the study of biological and other weakly scattering samples. The method is applied, using X-ray illumination, to quantitative imaging of the granular precursors of underwater adhesive produced by the marine sandcastle worm, Phragmatopoma californica. We are able to observe the internal structure of the adhesive precursors in a number of states.


Assuntos
Adesivos/química , Poliquetos/química , Algoritmos , Animais , Processamento de Imagem Assistida por Computador , Microscopia/métodos , Estrutura Molecular , Proteínas/química , Difração de Raios X/métodos , Difração de Raios X/estatística & dados numéricos
15.
Opt Lett ; 36(11): 1954-6, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21633413

RESUMO

As the resolution in coherent diffractive imaging improves, interexposure and intraexposure sample dynamics, such as motion, degrade the quality of the reconstructed image. Selecting data sets that include only exposures where tolerably little motion has occurred is an inefficient use of time and flux, especially when detector readout time is significant. We provide an experimental demonstration of an approach in which all images of a data set exhibiting sample motion are combined to improve the quality of a reconstruction. This approach is applicable to more general sample dynamics (including sample damage) that occur during measurement.

16.
Phys Rev Lett ; 106(1): 013903, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21231742

RESUMO

This Letter demonstrates that coherent diffractive imaging (CDI), in combination with phase-diversity methods, provides reliable and artefact free high-resolution images. Here, using x rays, experimental results show a threefold improvement in the available image contrast. Furthermore, in conditions requiring low imaging dose, it is demonstrated that phase-diverse CDI provides a factor of 2 improvement in comparison to previous CDI techniques.

17.
Eur J Radiol ; 68(3 Suppl): S49-53, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18599236

RESUMO

Analyser-based phase contrast X-ray imaging can provide high-contrast images of biological tissues with exquisite sensitivity to the boundaries between tissues. The phase and absorption information can be extracted by processing multiple images acquired at different analyser orientations. Recording both the transmitted and diffracted beams from a thin Laue analyser crystal can make phase retrieval possible for dynamic systems by allowing full field imaging. This technique was used to image the thorax of a mechanically ventilated newborn rabbit pup using a 25 keV beam from the SPring-8 synchrotron radiation facility. The diffracted image was produced from the (111) planes of a 50 mm x 40 mm, 100 microm thick Si analyser crystal in the Laue geometry. The beam and analyser were large enough to image the entire chest, making it possible to observe changes in anatomy with high contrast and spatial resolution.


Assuntos
Imageamento Tridimensional/veterinária , Radiografia Torácica/veterinária , Refratometria/veterinária , Tomografia por Raios X/veterinária , Algoritmos , Animais , Animais Recém-Nascidos , Cães , Imageamento Tridimensional/métodos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Refratometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia por Raios X/métodos
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