@article{39412, abstract = {{ The Eringen’s nonlocal elastica equation does not possess a Lagrangian formulation. In this article, we find a variational integrating factor which enables us to provide a Lagrangian and Hamiltonian structure associated to this equation. Explicit expressions of the solutions in terms of elliptic integrals of the first kind are then deduced. We then derive discrete version of the Eringen’s nonlocal elastica preserving the Lagrangian and Hamiltonian structure and compare it with Challamel’s and co-worker definition of a discrete Eringen’s nonlocal elastica. }}, author = {{Cresson, Jacky and Hariz-Belgacem, Khaled}}, issn = {{1081-2865}}, journal = {{Mathematics and Mechanics of Solids}}, keywords = {{Mechanics of Materials, General Materials Science, General Mathematics}}, publisher = {{SAGE Publications}}, title = {{{About the structure of the discrete and continuous Eringen’s nonlocal elastica}}}, doi = {{10.1177/10812865221108094}}, year = {{2022}}, } @article{39400, abstract = {{ The Eringen’s nonlocal elastica equation does not possess a Lagrangian formulation. In this article, we find a variational integrating factor which enables us to provide a Lagrangian and Hamiltonian structure associated to this equation. Explicit expressions of the solutions in terms of elliptic integrals of the first kind are then deduced. We then derive discrete version of the Eringen’s nonlocal elastica preserving the Lagrangian and Hamiltonian structure and compare it with Challamel’s and co-worker definition of a discrete Eringen’s nonlocal elastica. }}, author = {{Cresson, Jacky and Hariz Belgacem, Khaled}}, issn = {{1081-2865}}, journal = {{Mathematics and Mechanics of Solids}}, keywords = {{Mechanics of Materials, General Materials Science, General Mathematics}}, publisher = {{SAGE Publications}}, title = {{{About the structure of the discrete and continuous Eringen’s nonlocal elastica}}}, doi = {{10.1177/10812865221108094}}, year = {{2022}}, } @article{46479, author = {{Bobzin, K. and Kalscheuer, C. and Grundmeier, Guido and Kollmann, S. and Carlet, M. and de los Arcos de Pedro, Maria Teresa}}, issn = {{0257-8972}}, journal = {{Surface and Coatings Technology}}, keywords = {{Materials Chemistry, Surfaces, Coatings and Films, Surfaces and Interfaces, Condensed Matter Physics, General Chemistry}}, publisher = {{Elsevier BV}}, title = {{{Oxidation stability of chromium aluminum oxynitride hard coatings}}}, doi = {{10.1016/j.surfcoat.2022.128927}}, volume = {{449}}, year = {{2022}}, } @article{32088, abstract = {{Subwavelength dielectric resonators assembled into metasurfaces have become a versatile tool for miniaturizing optical components approaching the nanoscale. An important class of metasurface functionalities is associated with asymmetry in both the generation and transmission of light with respect to reversals of the positions of emitters and receivers. The nonlinear light–matter interaction in metasurfaces offers a promising pathway towards miniaturization of the asymmetric control of light. Here we demonstrate asymmetric parametric generation of light in nonlinear metasurfaces. We assemble dissimilar nonlinear dielectric resonators into translucent metasurfaces that produce images in the visible spectral range on being illuminated by infrared radiation. By design, the metasurfaces produce different and completely independent images for the reversed direction of illumination, that is, when the positions of the infrared emitter and the visible light receiver are exchanged. Nonlinearity-enabled asymmetric control of light by subwavelength resonators paves the way towards novel nanophotonic components via dense integration of large quantities of nonlinear resonators into compact metasurface designs.}}, author = {{Kruk, Sergey S. and Wang, Lei and Sain, Basudeb and Dong, Zhaogang and Yang, Joel and Zentgraf, Thomas and Kivshar, Yuri}}, issn = {{1749-4885}}, journal = {{Nature Photonics}}, keywords = {{Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}}, pages = {{561–565}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Asymmetric parametric generation of images with nonlinear dielectric metasurfaces}}}, doi = {{10.1038/s41566-022-01018-7}}, volume = {{16}}, year = {{2022}}, } @article{29790, abstract = {{The free exciton transition (near-band-edge emission, NBE) of ZnO at ≈388 nm can be strongly enhanced and even stimulated by an underlying photonic structure. 1D Photonic crystals, so-called distributed Bragg reflectors, are utilized to suppress the deep-level emission of ZnO (DLE, ≈500–530 nm). The reflector stacks are fabricated in a layer-by-layer procedure by wet-chemical synthesis. They consist of low-ε porous SiO2 layers and high-ε TiO2 layers. Varying the thickness of the SiO2 layers allows tuning the optical bandgap in a wide range between ≈420 and 800 nm. A ZnO layer is deposited on top of the reflector stacks by sol–gel synthesis. The spontaneous photoluminescence (PL) emission of the ZnO film is modulated by the photonic structure. When the optical bandgap of the reflector is in resonance with the deep-level emission of ZnO (DLE, ≈500–530 nm), then this defect-related emission mode is suppressed. Strong NBE emission is observed even when the ZnO layer does not show any NBE emission (due to low crystallinity) in the absence of the photonic structure. With this cost-efficient synthesis method, emitters for, e.g., luminescent gas sensors can be fabricated.}}, author = {{Kothe, Linda and Albert, Maximilian and Meier, Cedrik and Wagner, Thorsten and Tiemann, Michael}}, issn = {{2196-7350}}, journal = {{Advanced Materials Interfaces}}, keywords = {{Mechanical Engineering, Mechanics of Materials}}, publisher = {{Wiley}}, title = {{{Stimulation and Enhancement of Near‐Band‐Edge Emission in Zinc Oxide by Distributed Bragg Reflectors}}}, doi = {{10.1002/admi.202102357}}, volume = {{9}}, year = {{2022}}, } @article{51197, abstract = {{Clinching is a cost efficient method for joining components in series production. To assure the clinch point’s quality, the force displacement curve during clinching or the bottom thickness are monitored. The most significant geometrical characteristics of the clinch point, neck thickness and undercut, are usually tested destructively by microsectioning. However, micrograph preparation goes ahead with a resetting of elastic deformations and crack-closing after unloading. To generate a comprehensive knowledge of the clinch point’s inner geometry under load, in-situ computed tomography (CT) and acoustic testing (TDA) can be combined. While the TDA is highly sensitive to the inner state of the clinch point, it could detect critical events like crack development during loading. If such events are indicated, the loading process is stopped and a stepped in-situ CT of the following crack and deformation development is performed. In this paper, the concept is applied to the process of clinching itself, providing a detailed three-dimensional insight in the development of the joining zone. A test set-up is used which allows a stepwise clinching of two aluminium sheets EN AW 6014. Furthermore, this set-up is positioned within a CT system. In order to minimize X-ray absorption, a beryllium cylinder is used within the set-up frame and clinching tools are made from Si3N4. The actuator and sensor necessary for the TDA are integrated in the set-up. In regular process steps, the clinching process is interrupted in order to perform a TDA and a CT scan. In order to enhance the visibility of the interface, a thin tin layer is positioned between the sheets prior clinching. It is shown, that the test-set up allows a monitoring of the dynamic behaviour of the specimen during clinching while the CT scans visualize the inner geometry and material flow non-destructively.}}, author = {{Köhler, Daniel and Stephan, Richard and Kupfer, Robert and Troschitz, Juliane and Brosius, Alexander and Gude, Maik}}, issn = {{1662-9795}}, journal = {{Key Engineering Materials}}, keywords = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}}, pages = {{1489--1497}}, publisher = {{Trans Tech Publications, Ltd.}}, title = {{{Investigations on Combined <i>In Situ</i> CT and Acoustic Analysis during Clinching}}}, doi = {{10.4028/p-32330d}}, volume = {{926}}, year = {{2022}}, } @article{51193, author = {{Kupfer, Robert and Köhler, Daniel and Römisch, David and Wituschek, Simon and Ewenz, Lars and Kalich, Jan and Weiß, Deborah and Sadeghian, Behdad and Busch, Matthias and Krüger, Jan and Neuser, Moritz and Grydin, Olexandr and Böhnke, Max and Bielak, Christian-Roman and Troschitz, Juliane}}, issn = {{2666-3309}}, journal = {{Journal of Advanced Joining Processes}}, keywords = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}}, publisher = {{Elsevier BV}}, title = {{{Clinching of Aluminum Materials – Methods for the Continuous Characterization of Process, Microstructure and Properties}}}, doi = {{10.1016/j.jajp.2022.100108}}, volume = {{5}}, year = {{2022}}, } @article{51196, author = {{Meschut, G. and Merklein, M. and Brosius, A. and Drummer, D. and Fratini, L. and Füssel, U. and Gude, M. and Homberg, W. and Martins, P.A.F. and Bobbert, M. and Lechner, M. and Kupfer, R. and Gröger, B. and Han, D. and Kalich, J. and Kappe, F. and Kleffel, T. and Köhler, D. and Kuball, C.-M. and Popp, J. and Römisch, D. and Troschitz, J. and Wischer, C. and Wituschek, S. and Wolf, M.}}, issn = {{2666-3309}}, journal = {{Journal of Advanced Joining Processes}}, keywords = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}}, publisher = {{Elsevier BV}}, title = {{{Review on mechanical joining by plastic deformation}}}, doi = {{10.1016/j.jajp.2022.100113}}, volume = {{5}}, year = {{2022}}, } @article{52612, abstract = {{During resistance spot welding of zinc-coated advanced high-strength steels (AHSSs) for automotive production, liquid metal embrittlement (LME) cracking may occur in the event of a combination of various unfavorable influences. In this study, the interactions of different welding current levels and weld times on the tendency for LME cracking in third-generation AHSSs were investigated. LME manifested itself as high-penetration cracks around the circumference of the spot welds for welding currents closely below the expulsion limit. At the same time, the observed tendency for LME cracking showed no direct correlation with the overall heat input of the investigated welding processes. To identify a reliable indicator of the tendency for LME cracking, the local strain rate at the origin of the observed cracks was analyzed over the course of the welding process via finite element simulation. While the local strain rate showed a good correlation with the process-specific LME cracking tendency, it was difficult to interpret due to its discontinuous course. Therefore, based on the experimental measurement of electrode displacement during welding, electrode indentation velocity was proposed as a descriptive indicator for quantifying cracking tendency.}}, author = {{Böhne, Christoph and Meschut, Gerson and BIEGLER, MAX and RETHMEIER, MICHAEL}}, issn = {{0043-2296}}, journal = {{Welding Journal}}, keywords = {{Metals and Alloys, Mechanical Engineering, Mechanics of Materials}}, number = {{7}}, pages = {{197--207}}, publisher = {{American Welding Society}}, title = {{{The Influence of Electrode Indentation Rate on LME Formation during RSW}}}, doi = {{10.29391/2022.101.015}}, volume = {{101}}, year = {{2022}}, } @article{33687, author = {{Odziomek, Mateusz and Giusto, Paolo and Kossmann, Janina and Tarakina, Nadezda V. and Heske, Julian Joachim and Rivadeneira, Salvador M. and Keil, Waldemar and Schmidt, Claudia and Mazzanti, Stefano and Savateev, Oleksandr and Perdigón‐Toro, Lorena and Neher, Dieter and Kühne, Thomas and Antonietti, Markus and López‐Salas, Nieves}}, issn = {{0935-9648}}, journal = {{Advanced Materials}}, keywords = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}}, number = {{40}}, publisher = {{Wiley}}, title = {{{“Red Carbon”: A Rediscovered Covalent Crystalline Semiconductor}}}, doi = {{10.1002/adma.202206405}}, volume = {{34}}, year = {{2022}}, } @article{37713, author = {{Murzakhanov, Fadis F. and Mamin, Georgy Vladimirovich and Orlinskii, Sergei Borisovich and Gerstmann, Uwe and Schmidt, Wolf Gero and Biktagirov, Timur and Aharonovich, Igor and Gottscholl, Andreas and Sperlich, Andreas and Dyakonov, Vladimir and Soltamov, Victor A.}}, issn = {{1530-6984}}, journal = {{Nano Letters}}, keywords = {{Mechanical Engineering, Condensed Matter Physics, General Materials Science, General Chemistry, Bioengineering}}, number = {{7}}, pages = {{2718--2724}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Electron–Nuclear Coherent Coupling and Nuclear Spin Readout through Optically Polarized VB– Spin States in hBN}}}, doi = {{10.1021/acs.nanolett.1c04610}}, volume = {{22}}, year = {{2022}}, } @article{33080, author = {{Long, Teng and Ma, Xuekai and Ren, Jiahuan and Li, Feng and Liao, Qing and Schumacher, Stefan and Malpuech, Guillaume and Solnyshkov, Dmitry and Fu, Hongbing}}, issn = {{2198-3844}}, journal = {{Advanced Science}}, keywords = {{General Physics and Astronomy, General Engineering, Biochemistry, Genetics and Molecular Biology (miscellaneous), General Materials Science, General Chemical Engineering, Medicine (miscellaneous)}}, number = {{29}}, publisher = {{Wiley}}, title = {{{Helical Polariton Lasing from Topological Valleys in an Organic Crystalline Microcavity}}}, doi = {{10.1002/advs.202203588}}, volume = {{9}}, year = {{2022}}, } @article{22220, abstract = {{Abstract Developing resource-abundant and sustainable metal-free bifunctional oxygen electrocatalysts is essential for the practical application of zinc–air batteries (ZABs). 2D black phosphorus (BP) with fully exposed atoms and active lone pair electrons can be promising for oxygen electrocatalysts, which, however, suffers from low catalytic activity and poor electrochemical stability. Herein, guided by density functional theory (DFT) calculations, an efficient metal-free electrocatalyst is demonstrated via covalently bonding BP nanosheets with graphitic carbon nitride (denoted BP-CN-c). The polarized PN covalent bonds in BP-CN-c can efficiently regulate the electron transfer from BP to graphitic carbon nitride and significantly promote the OOH* adsorption on phosphorus atoms. Impressively, the oxygen evolution reaction performance of BP-CN-c (overpotential of 350 mV at 10 mA cm−2, 90\% retention after 10 h operation) represents the state-of-the-art among the reported BP-based metal-free catalysts. Additionally, BP-CN-c exhibits a small half-wave overpotential of 390 mV for oxygen reduction reaction, representing the first bifunctional BP-based metal-free oxygen catalyst. Moreover, ZABs are assembled incorporating BP-CN-c cathodes, delivering a substantially higher peak power density (168.3 mW cm−2) than the Pt/C+RuO2-based ZABs (101.3 mW cm−2). The acquired insights into interfacial covalent bonds pave the way for the rational design of new and affordable metal-free catalysts.}}, author = {{Wang, Xia and Kormath Madam Raghupathy, Ramya and Querebillo, Christine Joy and Liao, Zhongquan and Li, Dongqi and Lin, Kui and Hantusch, Martin and Sofer, Zdeněk and Li, Baohua and Zschech, Ehrenfried and Weidinger, Inez M. and Kühne, Thomas and Mirhosseini, Hossein and Yu, Minghao and Feng, Xinliang}}, journal = {{Advanced Materials}}, keywords = {{2D materials, bifunctional oxygen electrocatalysts, black phosphorus, oxygen evolution reaction, zinc–air batteries}}, number = {{20}}, pages = {{2008752}}, title = {{{Interfacial Covalent Bonds Regulated Electron-Deficient 2D Black Phosphorus for Electrocatalytic Oxygen Reactions}}}, doi = {{https://doi.org/10.1002/adma.202008752}}, volume = {{33}}, year = {{2021}}, } @article{31022, author = {{Abdelaty, Momen S. A. and Kuckling, Dirk}}, issn = {{0303-402X}}, journal = {{Colloid and Polymer Science}}, keywords = {{Materials Chemistry, Colloid and Surface Chemistry, Polymers and Plastics, Physical and Theoretical Chemistry}}, number = {{10}}, pages = {{1617--1629}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Altering of lower critical solution temperature of environmentally responsive poly (N-isopropylacrylamide-co-acrylic acid-co-vanillin acrylate) affected by acrylic acid, vanillin acrylate, and post-polymerization modification}}}, doi = {{10.1007/s00396-021-04882-x}}, volume = {{299}}, year = {{2021}}, } @article{34647, author = {{Brögelmann, T and Bobzin, K and Grundmeier, Guido and de los Arcos, T and Kruppe, N C and Schwiderek, S and Carlet, M}}, issn = {{0022-3727}}, journal = {{Journal of Physics D: Applied Physics}}, keywords = {{Surfaces, Coatings and Films, Acoustics and Ultrasonics, Condensed Matter Physics, Electronic, Optical and Magnetic Materials}}, number = {{3}}, publisher = {{IOP Publishing}}, title = {{{Durability of nanolayer Ti–Al–O–N hard coatings under simulated polycarbonate melt processing conditions}}}, doi = {{10.1088/1361-6463/ac2e31}}, volume = {{55}}, year = {{2021}}, } @article{34645, author = {{Tripathi, Tripurari Sharan and Wilken, Martin and Hoppe, Christian and de los Arcos, Teresa and Grundmeier, Guido and Devi, Anjana and Karppinen, Maarit}}, issn = {{1438-1656}}, journal = {{Advanced Engineering Materials}}, keywords = {{Condensed Matter Physics, General Materials Science}}, number = {{10}}, publisher = {{Wiley}}, title = {{{Atomic Layer Deposition of Copper Metal Films from Cu(acac) 2 and Hydroquinone Reductant}}}, doi = {{10.1002/adem.202100446}}, volume = {{23}}, year = {{2021}}, } @article{33587, abstract = {{Abstract We performed a virtual materials screening to identify promising topological materials for photocatalytic water splitting under visible light irradiation. Topological compounds were screened based on band gap, band edge energy, and thermodynamics stability criteria. In addition, topological types for our final candidates were computed based on electronic structures calculated usingthe hybrid density functional theory including exact Hartree–Fock exchange. Our final list contains materials which have band gaps between 1.0 and 2.7 eV in addition to band edge energies suitable for water oxidation and reduction. However, the topological types of these compounds calculated with the hybrid functional differ from those reported previously. To that end, we discuss the importance of computational methods for the calculation of atomic and electronic structures in materials screening processes.}}, author = {{Ranjbar, Ahmad and Mirhosseini, Hossein and Kühne, Thomas D}}, issn = {{2515-7639}}, journal = {{Journal of Physics: Materials}}, keywords = {{Condensed Matter Physics, General Materials Science, Atomic and Molecular Physics, and Optics}}, number = {{1}}, publisher = {{IOP Publishing}}, title = {{{On topological materials as photocatalysts for water splitting by visible light}}}, doi = {{10.1088/2515-7639/ac363d}}, volume = {{5}}, year = {{2021}}, } @article{33643, abstract = {{The origin of strong interactions between water molecules and porous C2N surfaces is investigated by using a combination of model materials, volumetric physisorption measurements, solid-state NMR spectroscopy, and DFT calculations.}}, author = {{Heske, Julian Joachim and Walczak, Ralf and Epping, Jan D. and Youk, Sol and Sahoo, Sudhir K. and Antonietti, Markus and Kühne, Thomas and Oschatz, Martin}}, issn = {{2050-7488}}, journal = {{Journal of Materials Chemistry A}}, keywords = {{General Materials Science, Renewable Energy, Sustainability and the Environment, General Chemistry}}, number = {{39}}, pages = {{22563--22572}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{When water becomes an integral part of carbon – combining theory and experiment to understand the zeolite-like water adsorption properties of porous C2N materials}}}, doi = {{10.1039/d1ta05122a}}, volume = {{9}}, year = {{2021}}, } @article{33655, abstract = {{Abstract Dual-ion batteries are considered to be an emerging viable energy storage technology owing to their safety, high power capability, low cost, and scalability. Intercalation of anions into a graphite positive electrode provides high operating voltage and improved energy density to such dual-ion batteries. In this work, we have performed a combinatorial study of graphite intercalation compounds considering four anions, namely hexafluorophosphate (PF 6 − ), perchlorate (ClO 4 − ), bis(fluorosulfonyl)imide (FSI−), and bis(trifluoromethanesulfonyl)imide (TFSI−), via first-principles calculations. The structural properties and energetics of the intercalation compounds are compared based on different sizes, geometries, and the physical and chemical properties of the intercalated anions. The staging mechanism of anion intercalation into graphite and the specific capacities, and voltage profiles of the intercalated compounds are investigated. A comparison regarding battery electrochemistry is also done with available experimental observations. Our calculated intercalation energies and voltage profiles show that the initial anion intercalation into graphite is less favorable than subsequent ones for all the anions considered in this study. Although the effect of the size of anions in a graphite cathode on various properties of the intercalated compounds is not as significant as the size of cations in a graphite anode, some distinction between the studied anions can still be made. Among the studied anions, the intercalation compounds based on PF 6 − are the most stable ones. These PF 6 − anions cause relatively small structural deformations of the graphite and have the highest oxidative ability, highest onset voltage, and highest diffusion barrier along the graphene sheets. The overall small diffusion barriers of the anions within graphite explain the high rate capability of dual-ion batteries.}}, author = {{Chugh, Manjusha and Jain, Mitisha and Wang, Gang and Nia, Ali Shaygan and Mirhosseini, Hossein and Kühne, Thomas}}, issn = {{2053-1591}}, journal = {{Materials Research Express}}, keywords = {{Metals and Alloys, Polymers and Plastics, Surfaces, Coatings and Films, Biomaterials, Electronic, Optical and Magnetic Materials}}, number = {{8}}, publisher = {{IOP Publishing}}, title = {{{A combinatorial study of electrochemical anion intercalation into graphite}}}, doi = {{10.1088/2053-1591/ac1965}}, volume = {{8}}, year = {{2021}}, } @article{33651, author = {{Sahoo, Sudhir K. and Teixeira, Ivo F. and Naik, Aakash and Heske, Julian Joachim and Cruz, Daniel and Antonietti, Markus and Savateev, Aleksandr and Kühne, Thomas}}, issn = {{1932-7447}}, journal = {{The Journal of Physical Chemistry C}}, keywords = {{Surfaces, Coatings and Films, Physical and Theoretical Chemistry, General Energy, Electronic, Optical and Magnetic Materials}}, number = {{25}}, pages = {{13749--13758}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Photocatalytic Water Splitting Reaction Catalyzed by Ion-Exchanged Salts of Potassium Poly(heptazine imide) 2D Materials}}}, doi = {{10.1021/acs.jpcc.1c03947}}, volume = {{125}}, year = {{2021}}, }