Seismic full-waveform inversion tries to estimate subsurface medium parameters from seismic data. Areas with salt bodies are of particular interest because they often have hydrocarbon reservoirs on their sides or underneath. Accurate reconstruction geometry is a challenge for current techniques. This paper presents parametric level-set method the salt-bodies in inversion. We split model two parts: background velocity and body known but undetermined shape. The represented by function that...

Chirality in inorganic nanoparticles and nanostructures has gained increasing scientific interest, because of the possibility to tune their ability interact differently with left- right-handed circularly polarized light. In some cases, optical activity is hypothesized originate from a chiral morphology nanomaterial. However, quantifying degree chirality objects sizes tens nanometers far straightforward. Electron tomography offers faithfully retrieve three-dimensional nanomaterials, but only...

Electron tomography has become a commonly used tool to investigate the three-dimensional (3D) structure of nanomaterials, including colloidal nanoparticle assemblies. However, electron microscopy is typically done under high-vacuum conditions, requiring sample preparation for assemblies obtained by wet colloid chemistry methods. This involves solvent evaporation and deposition on solid support, which consistently alters organization. Here, we suggest using study in their original liquid...

Morphological characterization of nanoparticle assemblies and hybrid nanomaterials is critical in determining their structure-property relationships as well the development structures with desired properties. Electron tomography has become a widely utilized technique for three-dimensional assemblies. However, extraction quantitative morphological parameters from reconstructed volume can be complex labor-intensive task. In this study, we aim to overcome challenge by automating volumetric...

In seismic exploration, the delineation of large bodies with hard exterior contrasts but nearly constant interior properties is a challenge. Examples include salt diapirs, slabs, anhydrite or basalt layers. Salt geometries are particular interest because they often have hydrocarbon reservoirs on their sides underneath. This papers introduces parametric level-set method for reconstruction such in full-waveform inversion (FWI). The determines outline geometry and evolves during terms its...

The increasing use of metallic nanoparticles (NPs) is significantly advancing the field electrocatalysis. In particular, Cu/Ag bimetallic interfaces are widely used to enhance electrochemical CO2 reduction reaction (eCO2RR) toward CO and, more recently, C2 products. However, drastic changes in product distribution and performance when Cu@Ag core–shell configurations can often be observed under conditions, especially during first few minutes reaction. Possible structural that generate these...

Electron tomography is essential for investigating the three-dimensional (3D) structure of nanomaterials. However, many these materials, such as metal–organic frameworks (MOFs), are extremely sensitive to electron radiation, making it difficult acquire a series projection images without inducing electron-beam damage. Another significant challenge high contrast in high-angle annular dark field scanning transmission microscopy that can be expected nanocomposites composed metal nanoparticle and...

Electron tomography is a widely used technique for 3D structural analysis of nanomaterials, but it can cause damage to samples due high electron doses and long exposure times. To minimize such damage, researchers often reduce beam by acquiring fewer projections through tilt undersampling. However, this approach also introduce reconstruction artifacts insufficient sampling. Therefore, important determine the optimal number that minimizes both undersampling accurate reconstructions...

Binary tomography is concerned with the recovery of binary images from a few their projections (i.e., sums pixel values along various directions). To reconstruct an image noisy projection data, one can pose it as constrained least-squares problem. As constraints are nonconvex, many approaches for solving rely on either relaxing or heuristics. In this paper, we propose novel convex formulation, based Lagrange dual The resulting problem generalized least absolute shrinkage and selection...

3D characterization of assemblies nanoparticles is great importance to determine their structure–property connection. Such investigations become increasingly more challenging when the larger and compact. In this paper, we propose an optimized approach for electron tomography minimize artifacts related beam broadening in high angle annular dark-field scanning transmission microscopy mode. These are typically present at one side reconstructed data set thick nanoparticle assemblies. To overcome...

Inverse scattering is the process of estimating spatial distribution potential an object by measuring scattered wavefields around it. In this article, we consider reflection tomography high contrast objects that commonly occurs in ground-penetrating radar, exploration geophysics, terahertz imaging, ultrasound, and electron microscopy. Unlike conventional transmission tomography, regime severely ill-posed since measured contain far less frequency information target object. We propose a...

Summary With the advent of efficient seismic data acquisition, we are having a surplus data, which is improving imaging earth using full-waveform inversion. However, such inversion suffers from many issues, including (i) substantial network waiting time due to repeated communications function and gradient values in distributed environment, (ii) requirement sophisticated optimizer solve an optimization problem involving non-smooth regularizers. To circumvent these propose decentralized...

Journal Article Electron Tomography in Liquids: Characterizing Nanoparticle Self-Assemblies a Relevant Environment Get access Da Wang, Wang EMAT-University of Antwerp, BelgiumNANOlab Center Excellence, University Belgium Search for other works by this author on: Oxford Academic Google Scholar Daniel Arenas Esteban, Esteban Ajinkya Kadu, Kadu Ana Sánchez-Iglesias, Sánchez-Iglesias CIC biomaGUNE, Donostia-San Sebastián, SpainCentro de Investigación Biomédica en Red, Bioingeniería,...

Electron tomography has become a commonly used tool to investigate the three-dimensional (3D) structure of nanomaterials, including colloidal nanoparticle assemblies. However, electron microscopy is typically carried out under high vacuum conditions. Therefore, pre-treatment sample preparation needed for assemblies obtained by (wet) colloid chemistry methods, solvent evaporation and deposition on solid TEM support. As result this procedure, changes are consistently imposed actual...

We introduce single-shot X-ray tomography that aims to estimate the target image from a single cone-beam projection measurement. This linear inverse problem is extremely under-determined since measurements are far fewer than number of unknowns. Moreover, it more challenging conventional where sufficiently large angles forms measurements, allowing for simple inversion process. However, becomes less severe if only composed known shapes. Hence, shape prior transforms ill-posed estimation...

Full-waveform inversion attempts to estimate a high-resolution model of the Earth by inverting all seismic data. This procedure fails if contains high-contrast bodies such as salt and su ciently low frequencies are absent from Salt important for hydrocarbon exploration because oil or gas reservoirs often located on their sides underneath. We represent shape body with level set, constructed radial basis functions keep its dimensionality low. have shown earlier that can be completely recovered...

Reflection tomography is an inverse scattering technique that estimates the spatial distribution of object's permittivity by illuminating it with a probing pulse and measuring scattered wavefields receivers located on same side as transmitter. Unlike conventional transmission tomography, reflection regime severely ill-posed since measured contain far less frequency information about object. In this paper, we propose incremental inversion framework requires no initial target model, leverages...