375 results match your criteria: "Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons[Affiliation]"
Commun Chem
November 2023
Laboratory for Waste Management, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.
The understanding and prediction of mineral precipitation processes in porous media are relevant for various energy-related subsurface applications. While it is well known that thermodynamic effects can inhibit crystallization in pores with sizes <0.1 µm, the retarded observation of mineral precipitation as function of pore size is less explored.
View Article and Find Full Text PDFAdv Mater
February 2024
Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany.
Polymorphism (and its extended form - pseudopolymorphism) in solids is ubiquitous in mineralogy, crystallography, chemistry/biochemistry, materials science, and the pharmaceutical industries. Despite the difficulty of controlling (pseudo-)polymorphism, the realization of specific (pseudo-)polymorphic phases and associated boundary structures is an efficient route to enhance material performance for energy conversion and electromechanical applications. Here, this work applies the pseudopolymorphic phase (PP) concept to a thermoelectric copper sulfide, Cu S (x ≤ 0.
View Article and Find Full Text PDFInorg Chem
October 2023
Inorganic Chemistry and Centre for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Essen 45117, Germany.
Microsc Microanal
April 2023
Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich, Jülich 52425, Germany.
When using the unit cell average of first moment data from four-dimensional scanning transmission electron microscopy (4D-STEM) to characterize ferroelectric materials, a variety of sources of systematic errors needs to be taken into account. In particular, these are the magnitude of the acceleration voltage, STEM probe semi-convergence angle, sample thickness, and sample tilt out of zone axis. Simulations show that a systematic error of calculated electric fields using the unit cell averaged momentum transfer originates from violation of point symmetry within the unit cells.
View Article and Find Full Text PDFMicrosc Microanal
June 2023
Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich, 52425 Jülich, Germany.
We propose a modification of Wigner distribution deconvolution (WDD) to support live processing ptychography. Live processing allows to reconstruct and display the specimen transmission function gradually while diffraction patterns are acquired. For this purpose, we reformulate WDD and apply a dimensionality reduction technique that reduces memory consumption and increases processing speed.
View Article and Find Full Text PDFInorg Chem
October 2023
Institute of Materials Science, Technical University of Darmstadt, 64287 Darmstadt, Germany.
This work investigates the effect of copper substitution on the magnetic properties of SmCo thin films synthesized by molecular beam epitaxy. A series of thin films with varying concentrations of Cu were grown under otherwise identical conditions to disentangle structural and compositional effects on the magnetic behavior. The combined experimental and theoretical studies show that Cu substitution at the Co sites not only stabilizes the formation of the SmCo structure but also enhances magnetic anisotropy and coercivity.
View Article and Find Full Text PDFTrends Biochem Sci
November 2023
Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Germany; Institute of Molecular Physiology, Johannes Gutenberg University Mainz, Mainz, Germany. Electronic address:
Structural and evolutionary studies of cyanobacterial phage shock protein A (PspA) and inner membrane-associated protein of 30 kDa (IM30) have revealed that these proteins belong to the endosomal sorting complex required for transport-III (ESCRT-III) superfamily, which is conserved across all three domains of life. PspA and IM30 share secondary and tertiary structures with eukaryotic ESCRT-III proteins, whilst also oligomerizing via conserved interactions. Here, we examine the structures of bacterial ESCRT-III-like proteins and compare the monomeric and oligomerized forms with their eukaryotic counterparts.
View Article and Find Full Text PDFiScience
September 2023
Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University, Tancha, Onna-son, Okinawa 904-0495, Japan.
Nat Nanotechnol
December 2023
Department of Physics, Indian Institute of Technology Patna, Bihar, India.
Dirac materials are characterized by the emergence of massless quasiparticles in their low-energy excitation spectrum that obey the Dirac Hamiltonian. Known examples of Dirac materials are topological insulators, d-wave superconductors, graphene, and Weyl and Dirac semimetals, representing a striking range of fundamental properties with potential disruptive applications. However, none of the Dirac materials identified so far shows metallic character.
View Article and Find Full Text PDFAdv Healthc Mater
December 2023
University Duisburg-Essen, Technical Chemistry I, Universitaetsstr. 7, 45141, Essen, Germany.
The bactericidal effects of silver nanoparticles (Ag NPs) against infectious strains of multiresistant bacteria is a well-studied phenomenon, highly relevant for many researchers and clinicians battling bacterial infections. However, little is known about the uptake of the Ag NPs into the bacteria, the related uptake mechanisms, and how they are connected to antimicrobial activity. Even less information is available on AgAu alloy NPs uptake.
View Article and Find Full Text PDFJ Appl Crystallogr
August 2023
Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom.
An interactive simulation of a transmission electron microscope (TEM) called is developed here, which enables users to understand how to operate and control an electron beam without the need to access an instrument. allows users to familiarize themselves with alignment procedures offline, reducing the time and money required to become a proficient TEM operator. In addition to teaching the basics of electron beam alignments, the software enables users to create bespoke microscope configurations and develop an understanding of how to operate the configurations without sitting at a microscope.
View Article and Find Full Text PDFACS Nano
August 2023
Maastricht MultiModal Molecular Imaging Institute (M4i), Maastricht University, 6200 MD Maastricht, The Netherlands.
Cryogenic electron microscopy can provide high-resolution reconstructions of macromolecules embedded in a thin layer of ice from which atomic models can be built . However, the interaction between the ionizing electron beam and the sample results in beam-induced motion and image distortion, which limit the attainable resolutions. Sample charging is one contributing factor of beam-induced motions and image distortions, which is normally alleviated by including part of the supporting conducting film within the beam-exposed region.
View Article and Find Full Text PDFNano Lett
August 2023
Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France.
The hallmark of spintronics has been the ability of spin-orbit interactions to convert a charge current into a spin current and vice versa, mainly in the bulk of heavy metal thin films. Here, we demonstrate how a light metal interface profoundly affects both the nature of spin-orbit torques and its efficiency in terms of damping-like () and field-like () effective fields in ultrathin Co films. We measure unexpectedly / ratios much larger than 1 by inserting a nanometer-thin Al metallic layer in Pt|Co|Al|Pt as compared to a similar stacking, including Cu as a reference.
View Article and Find Full Text PDFACS Appl Mater Interfaces
July 2023
Institute of Metallic Biomaterials, Helmholtz-Zentrum Hereon, Max-Planck-Strasse 1, Geesthacht 21502, Germany.
Functional materials feature hierarchical microstructures that define their unique set of properties. The prediction and tailoring of these require a multiscale knowledge of the mechanistic interaction of microstructure and property. An important material in this respect is biodegradable magnesium alloys used for implant applications.
View Article and Find Full Text PDFUltramicroscopy
November 2023
Department of Chemistry and Centre for NanoScience, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 Munich, Germany; Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C), Forschungszentrum Jülich, 52425 Jülich, Germany. Electronic address:
Stray electric fields in free space generated by two biased gold needles have been quantified in comprehensive finite-element (FE) simulations, accompanied by first moment (FM) scanning TEM (STEM) and electron holography (EH) experiments. The projected electrostatic potential and electric field have been derived numerically under geometrical variations of the needle setup. In contrast to the FE simulation, application of an analytical model based on line charges yields a qualitative understanding.
View Article and Find Full Text PDFMicrob Biotechnol
January 2024
Institute of Molecular Enzyme Technology (IMET), Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
Pseudomonas species have become promising cell factories for the production of natural products due to their inherent robustness. Although these bacteria have naturally evolved strategies to cope with different kinds of stress, many biotechnological applications benefit from engineering of optimised chassis strains with specially adapted tolerance traits. Here, we explored the formation of outer membrane vesicles (OMV) of Pseudomonas putida KT2440.
View Article and Find Full Text PDFNat Commun
July 2023
Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52428, Jülich, Germany.
Magnetoelasticity is the bond between magnetism and mechanics, but the intricate mechanisms via which magnetic states change due to mechanical strain remain poorly understood. Here, we provide direct nanoscale observations of how tensile strain modifies magnetic domains in a ferromagnetic Ni thin plate using in situ Fresnel defocus imaging, off-axis electron holography and a bimetallic deformation device. We present quantitative measurements of magnetic domain wall structure and its transformations as a function of strain.
View Article and Find Full Text PDFIUCrJ
July 2023
Department of Chemistry and Centre for NanoScience, Ludwig-Maximilians-University Munich, Butenandtstrasse 11, 81377 Munich, Germany.
Structure determination of biological macromolecules using cryogenic electron microscopy is based on applying the phase object (PO) assumption and the weak phase object (WPO) approximation to reconstruct the 3D potential density of the molecule. To enhance the understanding of image formation of protein complexes embedded in glass-like ice in a transmission electron microscope, this study addresses multiple scattering in tobacco mosaic virus (TMV) specimens. This includes the propagation inside the molecule while also accounting for the effect of structural noise.
View Article and Find Full Text PDFiScience
June 2023
Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
We have investigated magnetism of the AlCoCrFeNi single-crystalline high-entropy alloy. The material is nanostructured, composed of a B2 matrix with dispersed spherical-like A2 nanoparticles of average diameter 64 nm. The magnetism was studied from 2 to 400 K via direct-current magnetization, hysteresis curves, alternating-current magnetic susceptibility, and thermoremanent magnetization time decay, to determine the magnetic state that develops in this highly structurally and chemically inhomogeneous material.
View Article and Find Full Text PDFMembranes (Basel)
April 2023
Institute of Energy and Climate Research IEK-1, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
Dual-phase membranes are increasingly attracting attention as a solution for developing stable oxygen permeation membranes. CeGdO-FeCoO (CGO-F(3-x)CxO) composites are one group of promising candidates. This study aims to understand the effect of the Fe/Co-ratio, i.
View Article and Find Full Text PDFBiol Chem
June 2023
Ruhr University Bochum, Protein Crystallography, Department of Biophysics, Universitätsstraße 150, D-44780 Bochum, Germany.
The essential ATPase MsbA is a lipid flippase that serves as a prototype for multi drug resistant ABC transporters. Its physiological function is the transport of lipopolisaccharides to build up the outer membranes of Gram-negative bacteria. Although several structural and biochemical studies of MsbA have been conducted previously, a detailed picture of the dynamic processes that link ATP hydrolysis to allocrit transport remains elusive.
View Article and Find Full Text PDFPolymers (Basel)
April 2023
Helmholtz Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstr. 46, 48149 Münster, Germany.
Poly(ethylene oxide) block copolymers (PEO BCP) have been demonstrated to exhibit remarkably high lithium ion (Li) conductivity for Li batteries applications. For linear poly(isoprene)--poly(styrene)--poly(ethylene oxide) triblock copolymers (PIPSPEO), a pronounced maximum ion conductivity was reported for short PEO molecular weights around 2 kg mol. To later enable a systematic exploration of the influence of the PI and PS block lengths and related morphologies on the ion conductivity, a synthetic method is needed where the short PEO block length can be kept constant, while the PI and PS block lengths could be systematically and independently varied.
View Article and Find Full Text PDFMicroscopy (Oxf)
November 2023
DENSsolutions B.V., Informaticalaan 12, Delft 2628 ZD, The Netherlands.
Liquid-phase transmission electron microscopy (LPTEM) technique has been used to perform a wide range of in situ and operando studies. While most studies are based on the sample contrast change in the liquid, acquiring high qualitative results in the native liquid environment still poses a challenge. Herein, we present a novel and facile method to perform high-resolution and analytical electron microscopy studies in a liquid flow cell.
View Article and Find Full Text PDFUltramicroscopy
August 2023
Department of Chemistry, University College London, 20 Gordon St, London, WC1H 0AJ, United Kingdom. Electronic address:
Characterisation of the electron beams trajectory in an electron microscope is possible in a few select commercial software packages, but these tools and their source code are not available in a free and accessible manner. This paper introduces the free and open-source software TEMGYM Advanced, which implements ray tracing methods that calculate the path of electrons through a magnetic or electrostatic lens and allow evaluation of the first-order properties and third-order geometric aberrations. Validation of the aberration coefficient calculations is performed by implementing two independent methods - the aberration integral and differential algebra (DA) methods and by comparing the results of each.
View Article and Find Full Text PDFNat Commun
April 2023
Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Mainz, Germany.
Dynamin-like proteins are membrane remodeling GTPases with well-understood functions in eukaryotic cells. However, bacterial dynamin-like proteins are still poorly investigated. SynDLP, the dynamin-like protein of the cyanobacterium Synechocystis sp.
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