A single slice approach for simulating two-beam electron diffraction of nanocrystals

[EN] A simple computational method that can be used to simulate TEM image contrast of an electron beam diffracted by a crystal under two-beam dynamical scattering conditions is presented. The approach based on slicing the shape factor is valid for a general crystal morphology, with and without crystalline defects, avoids the column approximation, and provides the complex exit wave at the focal and the image planes also under weak-beam conditions. The approach is particularly efficient for large crystals and the 3D model required for the calculations can be measured experimentally using electron tomography. The method is applied to show that the shape of a diffracted spot can be affected by shifts, broadening and secondary maxima of appreciable intensity, even for a perfect crystal. The methodology is extended for the case of electron precession diffraction, and to show how can be used to improve nanometrology from diffraction patterns. The method is used also to perform simulations of simple models of crystalline defects. The accuracy of the method is demonstrated through examples of experimental and simulated dark-field images of MgO and ZrO2 nanocrystals and thin layers of CeO2

TEMAS: A Flexible Non-AI Algorithm for Metrology of Single-Core and Core-Shell Nanoparticles from TEM Images

An essential application of electron microscopy is to provide feedback to tune the fabrication of nanoparticles (NPs). Real samples tend to follow a size distribution commonly linked to the synthesis process used and in turn to their functional properties. This study presents an algorithm for measuring particle size distributions in electron microscopy images. State-of-the-art methods based on Artificial Intelligence (e.g., Deep Learning) require extensive datasets of labeled images similar to those expected to be analyzed, and extensive supervised re-training is often required for cross-domain application. In contrast, the non-AI algorithm described in this study is accurate and can be quickly set up for measuring new experimental images in different domains. The accuracy of the method is validated quantitatively and comparing graphical and descriptive statistics. Different size distributions are measured on images of platinum and gold nanocatalysts supported on carbon black, amorphous carbon, and titanium dioxide crystals. Also, images of platinum-iron core-shell NPs supported on thin amorphous carbon film are successfully analyzed. The limitation of evaluating different algorithms for NPs metrology is the lack of standards that different researchers can use as ground truth. In order to overcome this limitation, the images and the ground truth measurements presented here are shared as an open dataset. © 2023 The Authors. Particle & Particle Systems Characterization published by Wiley-VCH GmbH

Automatic segmentation of ventricular volume by 3D ultrasonography in post haemorrhagic ventricular dilatation among preterm infants

To train, evaluate, and validate the application of a deep learning framework in three-dimensional ultrasound (3D US) for the automatic segmentation of ventricular volume in preterm infants with post haemorrhagic ventricular dilatation (PHVD). We trained a 2D convolutional neural network (CNN) for automatic segmentation ventricular volume from 3D US of preterm infants with PHVD. The method was validated with the Dice similarity coefficient (DSC) and the intra-class coefficient (ICC) compared to manual segmentation. The mean birth weight of the included patients was 1233.1 g (SD 309.4) and mean gestational age was 28.1 weeks (SD 1.6). A total of 152 serial 3D US from 10 preterm infants with PHVD were analysed. 230 ventricles were manually segmented. Of these, 108 were used for training a 2D CNN and 122 for validating the methodology for automatic segmentation. The global agreement for manual versus automated measures in the validation data (n=122) was excellent with an ICC of 0.944 (0.874-0.971). The Dice similarity coefficient was 0.8 (+/- 0.01). 3D US based ventricular volume estimation through an automatic segmentation software developed through deep learning improves the accuracy and reduces the processing time needed for manual segmentation using VOCAL. 3D US should be considered a promising tool to help deepen our current understanding of the complex evolution of PHVD

Sensor de electrones para microscopía electrónica

This invention consists of an electron sensor (1) and a system with a plurality of electron sensors (1) for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam (10) that comprises at least one electron that impacts on a lateral reception surface (3) of said electron sensor (1) and this generates an electrical charge of hole-electron pairs (h-e) that are detected and/or measured by at least electrodes (6, 7) linked to an electric circuit unit (12) to form a high dynamic range image (11) and measure the energy of the electrons impacting each pixel of the image. [EN]La presente invención es un sensor de electrones (1), y un sistema con una pluralidad de sensores de electrones (1) para microscopía electrónica realizada mediante un microscopio electrónico. Más concretamente, el microscopio electrónico genera un haz de electrones (10) que comprende al menos un electrón que incide sobre una superficie de recepción lateral (3) de dicho sensor de electrones (1) y este genera una carga eléctrica de pares electrón-hueco (e-h) que son detectados y/o medidos por al menos electrodos (6,7) vinculados con una unidad de circuitería eléctrica (12) para formar una imagen (11) con elevado rango dinámico y medir la energía de los electrones incidentes en cada pixel de la imagen. [ES]Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patente con informe sobre el estado de la técnic

Sensor de electrones para microscopía electrónica

Sensor de electrones para microscopia electrónica. La presente invención es un sensor de electrones (1), y un sistema con una pluralidad de sensores de electrones (1) para microscopia electrónica realizada mediante un microscopio electrónico. Más concretamente, el microscopio electrónico genera un haz de electrones (10) que comprende al menos un electrón que incide sobre una superficie de recepción lateral (3) de dicho sensor de electrones (1) y este genera una carga eléctrica de pares electrón-hueco (e-h) que son detectados y/o medidos por al menos electrodos (6, 7) vinculados con una unidad de circuitería eléctrica (12) para formar una imagen (11) con elevado rango dinámico y medir la energía de los electrones incidentes en cada pixel de la imagen. [ES]This invention consists of an electron sensor (1) and a system with a plurality of electron sensors (1) for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam (10) that comprises at least one electron that impacts on a lateral reception surface (3) of said electron sensor (1) and this generates an electrical charge of hole-electron pairs (h-e) that are detected and/or measured by at least electrodes (6, 7) linked to an electric circuit unit (12) to form a high dynamic range image (11) and measure the energy of the electrons impacting each pixel of the image. [EN]Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patente con informe sobre el estado de la técnic

Sensor de electrones para microscopia electrónica

Sensor de electrones para microscopia electrónica. La presente invención es un sensor de electrones (1), y un sistema con una pluralidad de sensores de electrones (1) para microscopia electrónica realizada mediante un microscopio electrónico. Más concretamente, el microscopio electrónico genera un haz de electrones (10) que comprende al menos un electrón que incide sobre una superficie de recepción lateral (3) de dicho sensor de electrones (1) y este genera una carga eléctrica de pares electrón-hueco (e-h) que son detectados y/o medidos por al menos electrodos (6, 7) vinculados con una unidad de circuitería eléctrica (12) para formar una imagen (11) con elevado rango dinámico y medir la energía de los electrones incidentes en cada pixel de la imagenPeer reviewedConsejo Superior de Investigaciones Científicas (España)B1 Patente sin examen previ

Capteur d'électrons pour microscopie électronique

This invention is an electron sensor (1) and a system with a plurality of electron sensors (1) for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam (10) that comprises at least one electron that impacts on a lateral reception surface (3) of said electron sensor (1) and this generates an electrical charge of electron-hole (e-h) pairs that are detected and/or measured by at least electrodes (6, 7) linked to an electric circuit unit (12) to form a high dynamic range image (11) and measure the energy of the electrons impacting each pixel of the imagePeer reviewedConsejo Superior de Investigaciones Científicas (España)B1 Patente sin examen previ

Electron sensor for electron microscopy

An electron sensor and a system with a plurality of electron sensors for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam that includes at least one electron that impacts on a lateral reception surface of said electron sensor and this generates an electrical charge of electron-hole (e-h) pairs that are detected and/or measured by at least electrodes linked to an electric circuit unit to form a high dynamic range image and measure the energy of the electrons impacting each pixel of the imagePeer reviewedConsejo Superior de Investigaciones Científicas (España)B2 Patente con examen previ

Electron sensor for electron microscopy

An electron sensor and a system with a plurality of electron sensors for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam that includes at least one electron that impacts on a lateral reception surface of said electron sensor and this generates an electrical charge of electron-hole (e-h) pairs that are detected and/or measured by at least electrodes linked to an electric circuit unit to form a high dynamic range image and measure the energy of the electrons impacting each pixel of the imagePeer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patente con informe sobre el estado de la técnic

Electron sensor for electron microscopy

This invention is an electron sensor (1) and a system with a plurality of electron sensors (1) for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam (10) that comprises at least one electron that impacts on a lateral reception surface (3) of said electron sensor (1) and this generates an electrical charge of electron-hole (e-h) pairs that are detected and/or measured by at least electrodes (6, 7) linked to an electric circuit unit (12) to form a high dynamic range image (11) and measure the energy of the electrons impacting each pixel of the imagePeer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patente con informe sobre el estado de la técnic