Article
Polymer Science
L. M. Valencia, M. de la Mata, M. Herrera, F. J. Delgado, J. Hernandez-Saz, S. Molina
Summary: (S)TEM has valuable applications in materials science, but electron beam induced damage is a challenge for soft materials like acrylic resins. This study explores different methodologies for obtaining suitable resin specimens for (S)TEM analysis and investigates the mechanisms of electron beam induced degradation in acrylic resin and the critical doses involved.
POLYMER DEGRADATION AND STABILITY
(2022)
Article
Chemistry, Multidisciplinary
Viacheslav Shcherbakov, Sergey A. Denisov, Mehran Mostafavi
Summary: The catalytic effect of AuNPs on reactions involving radicals can significantly alter the composition and ratio of products by selectively oxidizing organic radicals. Additionally, the catalytic activity of AuNPs may impact the accuracy of determining reactive oxygen species concentration using organic dyes. Moreover, the role of AuNPs' catalytic activity in the radiosensitization effect for radiotherapy is actively being researched.
Article
Chemistry, Multidisciplinary
Xiaohui Song, Xingyu Zhang, Qiang Chang, Xin Yao, Mufan Li, Ruopeng Zhang, Xiaotao Liu, Chengyu Song, Yun Xin Angel Ng, Edison Huixiang Ang, Zihao Ou
Summary: The rapid advancement of transmission electron microscopy has led to revolutions in various fields, revealing the 3D information of each atom in nanoparticles and capturing the atomic structural kinetics in metal nanoparticles after phase transformation. Quantitative measurements of physical and chemical properties have been made, but high dose rates are incompatible with other ultrathin morphologies, limiting atomic electron tomography primarily to quasi-spherical nanoparticles. This study demonstrates the 3D atomic structure of a complex core-shell nanowire and shows that a new superthin noble metal layer can mitigate electron beam damage on ultrathin nanowires.
Article
Biochemistry & Molecular Biology
Bryan E. J. Lee, Liza-Anastasia DiCecco, Hourieh Exir, Arnaud Weck, Kyla N. Sask, Kathryn Grandfield
Summary: This study presents a successful methodology for imaging mammalian cells adhered to nanostructured titanium using SEM in low-vacuum mode following ionic liquid treatment. By combining different techniques, the shape and location of cells were confirmed to remain unchanged even after multiple irradiation sessions, indicating the potential of this technique for examining cellular behavior on biomaterials with submicron surface features. This demonstrated method has significant implications for understanding cell migration on nanostructured surfaces and exploring simpler SEM preparation methods for cellular imaging.
Article
Chemistry, Multidisciplinary
Ha Rim Lee, Da Woon Kim, Alfi Rodiansyah, Boklae Cho, Joonwon Lim, Kyu Chang Park
Summary: The structural properties of CNT cold cathodes, such as aspect ratio and tip diameter, significantly influence electron beam properties, including beam size and brightness, ultimately determining the resolution of secondary electron images obtained by SEM systems equipped with CNT cold cathode modules. Investigating these correlations is crucial for understanding the contributions of edge-emitted electrons to the total field emission current and establishing a basic model for advanced electron devices.
Article
Chemistry, Multidisciplinary
Junzhe Xiao, Yifan Cui, Can Li, Haibo Xu, Yizhan Zhai, Xue Zhang, Shengming Ma
Summary: The study developed a gold-catalyzed room temperature allenation of terminal alkynes with aldehydes, providing 1,3-disubstituted allenes with diverse functional groups, and demonstrated the practicality and synthetic potentials of this reaction. Mechanistic studies showed that the gold catalyst, the aldehyde effect, the fluoroalkyl hydroxyl solvent, and the structure of the amine are essential for this room temperature ATA reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Ondrej Dyck, Andrew R. Lupini, Stephen Jesse
Summary: In this study, we demonstrate an electron beam direct-write process in an aberration-corrected scanning transmission electron microscope. This process differs from conventional electron-beam-induced deposition techniques as it uses a different mechanism and elemental tin (Sn) as a precursor to enable atom-by-atom direct writing. The atomic-sized electron beam is used to generate chemically reactive point defects in a graphene substrate, allowing the precursor atoms to migrate and bond to the defect sites for deposition.
Article
Chemistry, Multidisciplinary
Yanwei Cao, Yang Huang, Lin He
Summary: In this study, a step- and atom-economic synthesis of N-Boc amines from readily available substrates was reported. The catalytic system showed unique selectivity for N-Boc amines in good yields and demonstrated potential application prospects in industrial syntheses. Mechanistic investigations revealed that gold catalyzed the reaction and copper acted as an electron transfer mediator in the catalytic cycle.
Article
Chemistry, Multidisciplinary
Thais Couasnon, Birk Fritsch, Michael P. M. Jank, Roberts Blukis, Andreas Hutzler, Liane G. G. Benning
Summary: Liquid-Phase Transmission Electron Microscopy (LP-TEM) allows for in situ observations of materials in liquids with high resolution. The irradiation in LP-TEM alters the chemistry of the aqueous solution, affecting the observed reactions. By using goethite's morphological changes as a marker, the influence of radiation on solution chemistry is evaluated. The results provide insights into the interplay between redox reactions and acidity during radiation-induced chemical changes in LP-TEM, opening up new perspectives in studying dissolution processes in various settings.
Article
Engineering, Environmental
Juliana Mendonca Silva de Jesus, Flavio Kiyoshi Tominaga, Allan dos Santos Argolo, Ana Cristina Gomes Nascimento, Sueli Ivone Borrely, Daniel Perez Vieira, Daniele Maia Bila, Antonio Carlos Silva Costa Teixeira
Summary: This study investigates the feasibility of using ionizing sources to degrade progestins hormones in synthetic solutions and real pharmaceutical wastewater. The results show that LNG is more difficult to degrade compared to GES, and LNG exhibits greater reactivity with reducing species. Furthermore, the irradiation process reduces the toxicity of the substances to biological organisms.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Materials Science, Composites
An Zheng, Yingying Tang, Mingxin Zhang
Summary: The effect of electron beam irradiation on the mechanical properties of MUF impregnated wood has been investigated. Low-dose irradiation enhances the mechanical properties and reduces formaldehyde emission, while high-dose irradiation deteriorates the mechanical properties.
POLYMER COMPOSITES
(2022)
Article
Nanoscience & Nanotechnology
Lei Zheng, Urs Zywietz, Tobias Birr, Martin Duderstadt, Ludger Overmeyer, Bernhard Roth, Carsten Reinhardt
Summary: The study demonstrates a simple and low-cost method for rapid generation of high-resolution and accurate optical micro- and nanostructures using UV-LED projection photolithography. The developed system allows for the preparation of photonic devices with various geometrical complexities and dimensions from nanometers to centimeters.
MICROSYSTEMS & NANOENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
David Krug, Maximilian Widemann, Felix Gruber, Shamail Ahmed, Thomas Demuth, Andreas Beyer, Kerstin Volz
Summary: GaP nanowires grown via the VLS mechanism using TBP and TMGa as precursors in an in situ closed gas cell heating holder are studied. The nanowires change their growth direction after certain distances by producing kinks, and the dominant kink angles are found to arise from micro twins. Understanding the defect formation and geometric changes in GaP nanowires can enhance control over their shape during growth and facilitate the development of nanowire devices.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Lei Wang, Mengmeng Ma, Huiqiu Wang, Hao Xiong, Xiao Chen, Fei Wei, Boyuan Shen
Summary: Electron-induced structural changes in materials can be observed using electron microscopy, but it is challenging for beam-sensitive materials. In this study, a new technique was used to image a metal-organic framework, UiO-66 (Zr), at very low electron dose and dose rate, revealing missing organic linkers. The kinetics of missing linkers and lattice deformation were also observed. This research provides visual insight into electron-induced chemistry and helps prevent electron damage to sensitive materials.
Article
Construction & Building Technology
Tingxia Hu, Shanhong Sui, Jiale Li, Pengyi Zhang
Summary: Aldehydes, apart from formaldehyde, are commonly found in indoor environments and pose significant threats to human health. However, there have been limited efforts to catalytically decompose them at room temperature. In this study, hydrothermally synthesized weakly crystallized ultrafine MnO2 nanowires were used to decompose hexanal, a frequently detected indoor odorant. The nanowires formed a three-dimensional porous structure, exposing active sites. With its high specific surface area, abundant oxygen vacancies, and ability to generate superoxide radicals at room temperature, the MnO2 nanowires achieved fast and complete oxidation of hexanal at significantly lower temperatures compared to catalysts reported in previous literatures. Moreover, the nanowires exhibited excellent room-temperature catalytic activity for the removal of hexanal at ppb levels. This work demonstrates the feasibility of catalytically removing aldehydes other than formaldehyde at room temperature.
BUILDING AND ENVIRONMENT
(2022)
Review
Materials Science, Multidisciplinary
Yu Liu, Huy Q. Ta, Xiaoqin Yang, Yue Zhang, Junhua Zhou, Qitao Shi, Mengqi Zeng, Thomas Gemming, Barbara Trzebicka, Lei Fu, Mark H. Ruemmeli
Summary: This review focuses on the fabrication and characterization of free-standing nanostructures suspended in graphene using transmission electron microscopy, which enables the observations with atomic resolution and investigations of the dynamic behavior of atoms/structures in such materials. Additionally, the review discusses the influence of novel metal/nonmetal dopants in graphene vacancies with varying bond configurations and the catalytic activities of single atoms/clusters located at the graphene edges. Moreover, the dynamic forming process of freestanding single-atom-thick two-dimensional (2D) clusters/metal/metallenes and 2D clusters/metal/metallenes oxides is discussed.
SCIENCE CHINA-MATERIALS
(2023)
Article
Chemistry, Physical
Zequn Zhang, Simon Fellner, Sergey Ketov, Megan J. Cordill, Huaping Sheng, Christian Mitterer, Kaikai Song, Christoph Gammer, Juergen Eckert
Summary: The phase evolution of alloys and atomic diffusion are closely related. However, the influence of reactive diffusion on phase formation in high-entropy alloys (HEAs) is still not clear. This study investigates the phase evolution of a multicomponent CoCrFeNi/Al diffusion couple and reveals the combined effects of enthalpy and entropy on phase formation in HEAs at elevated temperatures. Surface modification of HEAs can be achieved through film deposition and annealing processes.
Article
Materials Science, Multidisciplinary
Panpan Zhao, Markus Gusenbauer, Harald Oezelt, Daniel Wolf, Thomas Gemming, Thomas Schrefl, Kornelius Nielsch, Thomas George Woodcock
Summary: In this study, aberration-corrected scanning transmission electron microscopy coupled with electron energy-loss spectroscopy was used to investigate the atomistic structure and chemical composition of twin boundaries in ferromagnetic r-MnAl-C. The results showed that there was Mn enrichment at both coherent and incoherent twin boundaries, and a transition region with Mn enrichment was found at order twin boundaries. Micromagnetic simulations revealed that increasing structural and chemical disorder at the interface led to an increase in coercivity.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Review
Electrochemistry
Baran Sarac, A. Sezai Sarac, Juergen Eckert
Summary: This review provides an introduction to the use of advanced amorphous metal catalysts for hydrogen storage and production via electrochemistry. Pd-based metallic glasses have gained significant attention due to their unique atomic structure and properties for energy applications. The review covers the fabrication techniques, hydrogen sorption, hydrogen evolution, kinetics, and future prospects of Pd-based metallic glasses. Overall, it offers a comprehensive overview for large-scale hydrogen energy storage and production systems.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Ming-Zhi Zhang, Kun Zhang, Kai-Kai Song, Xiao-Yu Zou, Wei-Dong Song, Ke-Feng Li, Li-Na Hu, Ze-Qun Zhang, Juergen Eckert
Summary: In this study, CoCrFeMnNi high-entropy alloys with a surface gradient nanostructure were produced using industrial shot blasting, which significantly improved their mechanical properties. The severely plastically deformed surface layer had a multi-scale hierarchical structure and increased in depth with shot-blasting time. The microhardness and tensile strength of the alloy were significantly higher after shot-blasting. The improved strain hardening and prevention of early necking in the gradient-nanostructured surface layer contributed to its high toughness.
Article
Chemistry, Physical
Monika Antoni, Florian Spieckermann, Niklas Plutta, Christoph Gammer, Marlene Kapp, Parthiban Ramasamy, Christian Polak, Reinhard Pippan, Michael J. J. Zehetbauer, Juergen Eckert
Summary: The effects of severe plastic deformation (SPD) by means of high-pressure torsion (HPT) on Fe73.9Cu1Nb3Si15.5B6.6 and Fe81.2Co4Si0.5B9.5P4Cu0.8 iron-based metallic glasses were compared. HPT processing extended the consolidation and deformation ranges for Fe73.9Cu1Nb3Si15.5B6.6, and achieved consolidation and deformation with minimum cracks for Fe81.2Co4Si0.5B9.5P4Cu0.8 for the first time. Various analyses revealed that Fe81.2Co4Si0.5B9.5P4Cu0.8 exhibited HPT-induced crystallization phenomena, while Fe73.9Cu1Nb3Si15.5B6.6 did not crystallize even at high HPT-deformation degrees.
Review
Chemistry, Multidisciplinary
Jinbo Pang, Songang Peng, Chongyang Hou, Hongbin Zhao, Yingju Fan, Chen Ye, Nuo Zhang, Ting Wang, Yu Cao, Weijia Zhou, Ding Sun, Kai Wang, Mark H. Rummeli, Hong Liu, Gianaurelio Cuniberti
Summary: Graphene remains of great interest in biomedical applications due to its biocompatibility. This review provides an update on the recent progress in graphene-based sensors for mimicking human senses, including artificial retina for image sensors, artificial eardrums, gas sensors, chemical sensors, and tactile sensors. It also discusses brain-like processors based on conventional transistors and memristor-related neuro-morphic computing, as well as the introduction of brain-machine interface. Additionally, the article summarizes the use of graphene-based artificial muscles as actuators to interact with the physical world. Future opportunities for improving human-like sensors and their clinical applications are highlighted.
Article
Chemistry, Multidisciplinary
Umar Rashid, Elarbi Chatir, Leonardo Medrano Sandonas, P. A. Sreelakshmi, Arezoo Dianat, Rafael Gutierrez, Gianaurelio Cuniberti, Saioa Cobo, Veerabhadrarao Kaliginedi
Summary: By using a mechanically controllable break junction technique, we created an ideal single molecular linear actuator based on dithienylethene (DTE) molecular architecture. This actuator undergoes reversible photothermal isomerization when exposed to UV irradiation under normal conditions, achieving both open and closed forms. Interestingly, the actuation occurs without altering the molecular junction's conductivity around the Fermi level, making it an essential property for an ideal single molecular actuator. Our study demonstrates a unique example of achieving a perfect balance between tunneling width and barrier height change during photothermal isomerization, resulting in no conductivity change but a change in molecular length for mechanical actuation at the single molecular level.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Engineering, Electrical & Electronic
Waltenegus Dargie, Jianjun Wen, Luis Antonio Panes-Ruiz, Leif Riemenschneider, Bergoi Ibarlucea, Gianaurelio Cuniberti
Summary: Human beings live and work in close proximity to dangerous gases, which can cause considerable damages to human lives and properties, as well as have high impact on the environment. Hence, diligent monitoring and management of these gases are of profound importance.
IEEE SENSORS JOURNAL
(2023)
Article
Computer Science, Artificial Intelligence
Tianfei Zhou, Fatih Porikli, David J. Crandall, Luc Van Gool, Wenguan Wang
Summary: Video segmentation is crucial in various practical applications such as enhancing visual effects in movies, understanding scenes in autonomous driving, and creating virtual background in video conferencing. Deep learning-based approaches have shown promising performance in video segmentation. This survey comprehensively reviews two main research lines - generic object segmentation and video semantic segmentation - by introducing their task settings, background concepts, need, development history, and challenges. Representative literature and datasets are also discussed, and the reviewed methods are benchmarked on well-known datasets. Open issues and opportunities for further research are identified, and a public website is provided to track developments in this field: https://github.com/tfzhou/VS-Survey.
IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE
(2023)
Article
Engineering, Manufacturing
Ruiqi Wang, Lixia Xi, Lili Feng, Baran Sarac, Konda Gokuldoss Prashanth, Juergen Eckert, Dongdong Gu
Summary: Dual-phase reinforcing approach is an efficient strategy for fabricating advanced aluminum matrix composites. However, designing a dual-phase reinforcing system with synergistic strengthening effect for LPBF process is challenging.
3D PRINTING AND ADDITIVE MANUFACTURING
(2023)
Article
Materials Science, Multidisciplinary
Marietta Seifert, Barbara Leszczynska, Robert Weser, Siegfried Menzel, Thomas Gemming, Hagen Schmidt
Summary: TiAl-based SAW devices were prepared by depositing Ti/Al multilayers on high-temperature stable CTGS substrates, and characterized for their durability and electrical behavior at intermediate high temperatures. The devices exhibited sufficient stability and a linear dependence of the resonant frequency on temperature, making them suitable for long-term applications.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Zahra Hajiahmadi, Mohammad Khazaei, Ahmad Ranjbar, Alireza Mostafaei, Sergii Chertopalov, Thomas D. Kuehne, Gianaurelio Cuniberti, Hamid Hosano, Hannes Raebiger, Kaoru Ohno
Summary: Using first-principles calculations, we investigated the electronic and optical properties of C60 adsorbed on monolayers of Ti2C and Ti3C2, as well as functionalized Ti2CT2 and Ti3C2T2 with T = F, OH, or O. The nature of the contact between C60 and Ti2CT2/Ti3C2T2 depends on the work function of the monolayer. The heterostructures of C60 on Ti2CT2 and Ti3C2T2 with ultrahigh or ultralow work functions exhibit Ohmic contacts. All constructed heterostructures, regardless of being metallic or semiconducting, show good light absorption in the visible region.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Construction & Building Technology
Jitong Zhao, George Karalis, Marco Liebscher, Lazaros Tzounis, Thomas Koeberle, Dieter Fischer, Frank Simon, Muhannad Al Aiti, Gianaurelio Cuniberti, Viktor Mechtcherine
Summary: This proof-of-concept study demonstrates the fabrication of a multifunctional reinforcing grid-building material within a thermoelectric element generator configuration. Carbon fiber yarns were impregnated with a geopolymer-based suspension and tested for their properties. The resulting hardened mineral-impregnated carbon-fiber reinforcements were used as thermoelements to assemble a grid-like TEG, which generated power upon exposure to a temperature difference.
ENERGY AND BUILDINGS
(2023)
Article
Nanoscience & Nanotechnology
Yanyu Lin, Zhangyuan Yan, Chi Shing Tsang, Lok Wing Wong, Xiaodong Zheng, Fangyuan Zheng, Jiong Zhao, Ke Chen
Summary: Recent advancements in TEM have enabled the study of atomic structures at unprecedented small scales. However, accurately detecting atomic positions from TEM images remains challenging, especially in the presence of background noise or contamination. To overcome this, AtomID-Net, a deep neural network model, is introduced for atomic detection from low-SNR experimental images in STEM. The model, trained on real images, achieves robust and efficient detection even in the presence of noise and contamination, outperforming existing peak-finding algorithms.
