TY - CONF AU - Sander, Tom AU - Lange, Sven AU - Hilleringmann, Ulrich AU - Geneis, Volker AU - Hedayat, Christian AU - Kuhn, Harald AU - Gockel, Franz-Barthold ID - 39392 T2 - 2021 22nd IEEE International Conference on Industrial Technology (ICIT) TI - Detection of Defects on Irregular Structured Surfaces by Image Processing Methods for Feature Extraction ER - TY - CONF AU - Lange, Sven AU - Schroder, Dominik AU - Hedayat, Christian AU - Kuhn, Harald AU - Hilleringmann, Ulrich ID - 39390 T2 - 2021 22nd IEEE International Conference on Industrial Technology (ICIT) TI - Development of Methods for Coil-Based Localization by Magnetic Fields of Miniaturized Sensor Platforms in Bioprocesses ER - TY - CHAP AU - Hilleringmann, Ulrich ID - 39394 SN - 9780128189009 T2 - Nanostructured Zinc Oxide TI - ZnO nanoparticle films as active layer for thin film transistors ER - TY - CONF AU - Reker, Julia AU - Meyers, Thorsten AU - Vidor, Fabio F. AU - Joubert, Trudi-Heleen AU - Hilleringmann, Ulrich ID - 39396 T2 - 2021 Smart Systems Integration (SSI) TI - Complementary Inverter Circuits on Flexible Substrates ER - TY - CONF AU - Reker, Julia AU - Meyers, Thorsten AU - Vidor, Fabio F. AU - Joubert, Trudi-Heleen AU - Hilleringmann, Ulrich ID - 39388 T2 - 2021 IEEE International Conference on Flexible and Printable Sensors and Systems (FLEPS) TI - Integration Process for Self-aligned Sub-µm Thin-Film Transistors for Flexible Electronics ER - TY - GEN ID - 41288 TI - Entwicklung einer konstruktionsbasierten französischen Grammatik: ein Arbeitsbericht zum Adjektiv- und Nominalbandd ER - TY - BOOK AU - Siepmann, Dirk AU - Bürgel, Christoph ID - 41221 TI - Grammatik des gesprochenen und geschriebenen Französisch: Das Nomen, VL - 2 ER - TY - GEN ID - 41269 TI - Lexiko-grammatische Konstruktionen als Kern der Spracharbeit im Spanischunterricht, in: Hispanorama ER - TY - GEN ID - 41267 TI - Hörverstehenskompetenz: Spanischstudierende auf dem Prüfstand der Abituraufgaben ER - TY - JOUR AU - Burgfeld-Meise, Bianca AU - Dehmel, Lukas ID - 43148 JF - Zeitschrift MedienPädagogik 42 TI - Subjektwissen als Bildungsperspektive junger Erwachsener. Self-Tracking-Apps als digitale Optimierungstechnologien im Spannungsgefüge von Kontrolle und Selbstermächtigung ER - TY - JOUR AU - Damm, Jannis AU - Albiez, Matthias AU - Göddecke, Johannes AU - Meschut, Gerson AU - Ummenhofer, Thomas ID - 43159 IS - 9 JF - adhäsion KLEBEN & DICHTEN KW - Polymers and Plastics KW - General Chemical Engineering KW - General Chemistry SN - 1619-1919 TI - Dämpfungseigenschaften geklebter Verbindungen - Potenzialanalyse und Klebstoffcharakterisierung VL - 65 ER - TY - JOUR AB - Der Beitrag referiert Ergebnisse studentischer Forschungsprojekte, die sich mit den Folgen der Corona-Pandemie für die berufliche Bildung, für Berufswahl, Berufsvorbereitung und Ausbildung befasst haben. Die Ergebnisse zeigen nicht nur, wie unterschiedlich Berufe und Branchen von der Krise betroffen waren und damit umgegangen sind, sondern geben auch Hinweise auf nötige Weiterentwicklungen zur Verbesserung der Resilienz von Branchen, Berufen, Betrieben und ihrer Ausbildung. AU - Heisler, Dietmar ID - 43179 JF - Berufsbildung. Zeitschrift für Theorie-Praxis-Dialog KW - Pandemie KW - Distanzlernen KW - Berufswahl KW - Ausbildung SN - 00059536 TI - Berufsausbildung in der Corona-Pandemie. Befunde studentischer Forschungsprojekte VL - 192 ER - TY - CHAP AU - Heisler, Dietmar AU - Reißland, Jens AU - Müller, Claudia AU - Rühr, Laura AU - Gröger, Simon ED - Melzig, Christian ED - Kuhlmeier, Werner ED - Kretschmer, Susanne ID - 43182 SN - 978-3-8474-2951-7 T2 - Berufsbildung für nachhaltige Entwicklung. Die Modellversuche 2015-2019 auf dem Weg vom Projekt zur Struktur TI - Das Analyseraster zu Merkmalen eines nachhaltigen Lernortes für betriebliche Ausbilderinnen und Ausbilder. ER - TY - JOUR AB - Im Fokus steht das Problem der Durchlässigkeit von akademischer und beruflicher Bildung im Kontext aktueller Reformen. Die Erhöhung sozialer Mobilität als Reformziel gerät darin zugunsten der Attraktivitätssteigerung von Bildungsgängen aus dem Blick. Die geringe Durchlässigkeit von Bildungsgängen wird primär als Marketingproblem thematisiert. AU - Heisler, Dietmar ID - 43178 JF - Berufsbildung. Zeitschrift für Theorie-Praxis-Dialog KW - allgemeine Bildung KW - berufliche BIldung KW - Durchlässigkeit im Bildungssystem SN - 00059536 TI - Berufsausbildung zwischen Attraktivitätsverlust und sozialer Ungleichheit Reformen für mehr Durchlässigkeit zwischen beruflicher und akademischer Bildung VL - 191 ER - TY - JOUR AB - We show the existence of ground states in the massless spin boson model without any infrared regularization. Our proof is non-perturbative and relies on a compactness argument. It works for arbitrary values of the coupling constant under the hypothesis that the second derivative of the ground state energy as a function of a constant external magnetic field is bounded. AU - Hasler, David AU - Hinrichs, Benjamin AU - Siebert, Oliver ID - 43465 IS - 1 JF - Communications in Mathematical Physics SN - 0010-3616 TI - On Existence of Ground States in the Spin Boson Model VL - 388 ER - TY - GEN AU - Schroeter-Wittke, Harald ID - 41089 SN - 0540–6226 T2 - Jahrbuch für Evangelische Kirchengeschichte des Rheinlandes TI - Andrea Strübind / Klaas-Dieter Voß (Hgg.), Märtyrerbücher und ihre Bedeutung für konfessionelle Identität und Spiritualität in der Frühen Neuzeit. Interkonfessionelle und interdisziplinäre Beiträge zur Erforschung einer Buchgattung (SMHR 109), Tübingen 2019 VL - 70 ER - TY - GEN AU - Schroeter-Wittke, Harald ID - 41087 SN - 0540–6226 T2 - Jahrbuch für Evangelische Kirchengeschichte des Rheinlandes TI - Stefan Alkier (Hg.), Sola Scriptura 1517-2017. Rekonstruktionen – Kritiken – Transformationen – Performanzen (CHTh 7), Tübingen 2019 VL - 70 ER - TY - CONF AU - Ahmed, Qazi Arbab ID - 29138 T2 - 2021 IFIP/IEEE 29th International Conference on Very Large Scale Integration (VLSI-SoC) TI - Hardware Trojans in Reconfigurable Computing ER - TY - JOUR AU - Schulze, Johanna ID - 43389 JF - GGG-Magazin: DIE SCHULE für alle TI - Einzelschulentwicklung gerecht und digital – Einblicke in die empirische Lage und Konsequenzen für die Praxis. VL - 4 ER - TY - BOOK AU - Schulze, Johanna ID - 43388 TI - Medienkonzepte zur chancengerechten Schulentwicklung. Fallstudien an Schulen mit besonders herausfordernden Schüler*innenkompositionen. ER - TY - JOUR AU - Luo, Kai Hong AU - Santandrea, Matteo AU - Stefszky, Michael AU - Sperling, Jan AU - Massaro, Marcello AU - Ferreri, Alessandro AU - Sharapova, Polina AU - Herrmann, Harald AU - Silberhorn, Christine ID - 26889 JF - Physical Review A SN - 2469-9926 TI - Quantum optical coherence: From linear to nonlinear interferometers ER - TY - JOUR AU - Lüders, Carolin AU - Pukrop, Matthias AU - Rozas, Elena AU - Schneider, Christian AU - Höfling, Sven AU - Sperling, Jan AU - Schumacher, Stefan AU - Aßmann, Marc ID - 26283 JF - PRX Quantum SN - 2691-3399 TI - Quantifying Quantum Coherence in Polariton Condensates ER - TY - JOUR AU - Bagrets, Dmitry AU - Kim, Kun Woo AU - Barkhofen, Sonja AU - De, Syamsundar AU - Sperling, Jan AU - Silberhorn, Christine AU - Altland, Alexander AU - Micklitz, Tobias ID - 26284 JF - Physical Review Research SN - 2643-1564 TI - Probing the topological Anderson transition with quantum walks ER - TY - JOUR AU - Xue, Yan AU - Chestnov, Igor AU - Sedov, Evgeny AU - Kiktenko, Evgeniy AU - Fedorov, Aleksey K. AU - Schumacher, Stefan AU - Ma, Xuekai AU - Kavokin, Alexey ID - 21362 IS - 1 JF - Physical Review Research SN - 2643-1564 TI - Split-ring polariton condensates as macroscopic two-level quantum systems VL - 3 ER - TY - JOUR AU - Jurgen von Bardeleben, Hans AU - Cantin, Jean-Louis AU - Gerstmann, Uwe AU - Schmidt, Wolf Gero AU - Biktagirov, Timur ID - 29747 IS - 19 JF - Nano Letters KW - Mechanical Engineering KW - Condensed Matter Physics KW - General Materials Science KW - General Chemistry KW - Bioengineering SN - 1530-6984 TI - Spin Polarization, Electron–Phonon Coupling, and Zero-Phonon Line of the NV Center in 3C-SiC VL - 21 ER - TY - JOUR AU - Slawig, Diana AU - Gruschwitz, Markus AU - Gerstmann, Uwe AU - Rauls, Eva AU - Tegenkamp, Christoph ID - 29748 IS - 36 JF - The Journal of Physical Chemistry C KW - Surfaces KW - Coatings and Films KW - Physical and Theoretical Chemistry KW - General Energy KW - Electronic KW - Optical and Magnetic Materials SN - 1932-7447 TI - Adsorption and Reaction of PbPc on Hydrogenated Epitaxial Graphene VL - 125 ER - TY - JOUR AU - Jain, Mitisha AU - Gerstmann, Uwe AU - Schmidt, Wolf Gero AU - Aldahhak, Hazem ID - 40250 IS - 6 JF - Journal of Computational Chemistry KW - Computational Mathematics KW - General Chemistry SN - 0192-8651 TI - Adatom mediated adsorption of N‐heterocyclic carbenes on Cu(111) and Au(111) VL - 43 ER - TY - JOUR AB - High harmonic generation (HHG) from solids shows great application prospects in compact short-wavelength light sources and as a tool for imaging the dynamics in crystals with subnanometer spatial and attosecond temporal resolution. However, the underlying collision dynamics behind solid HHG is still intensively debated and no direct mapping relationship between the collision dynamics with band structure has been built. Here, we show that the electron and its associated hole can be elastically scattered by neighboring atoms when their wavelength approaches the atomic size. We reveal that the elastic scattering of electron/hole from neighboring atoms can dramatically influence the electron recombination with its left-behind hole, which turns out to be the fundamental reason for the anisotropic interband HHG observed recently in bulk crystals. Our findings link the electron/hole backward scattering with Van Hove singularities and forward scattering with critical lines in the band structure and thus build a clear mapping between the band structure and the harmonic spectrum. Our work provides a unifying picture for several seemingly unrelated experimental observations and theoretical predictions, including the anisotropic harmonic emission in MgO, the atomic-like recollision mechanism of solid HHG, and the delocalization of HHG in ZnO. This strongly improved understanding will pave the way for controlling the solid-state HHG and visualizing the structure-dependent electron dynamics in solids. AU - Zuo, Ruixin AU - Trautmann, Alexander AU - Wang, Guifang AU - Hannes, Wolf-Rüdiger AU - Yang, Shidong AU - Song, Xiaohong AU - Meier, Torsten AU - Ciappina, Marcelo AU - Duc, Huynh Thanh AU - Yang, Weifeng ID - 37331 JF - Ultrafast Science SN - 2765-8791 TI - Neighboring Atom Collisions in Solid-State High Harmonic Generation VL - 2021 ER - TY - JOUR AB - AbstractMethylammonium lead iodide perovskite (MAPbI3) is renowned for an impressive power conversion efficiency rise and cost-effective fabrication for photovoltaics. In this work, we demonstrate that polycrystalline MAPbI3s undergo drastic changes in optical properties at moderate field strengths with an ultrafast response time, via transient Wannier Stark localization. The distinct band structure of this material - the large lattice periodicity, the narrow electronic energy bandwidths, and the coincidence of these two along the same high-symmetry direction – enables relatively weak fields to bring this material into the Wannier Stark regime. Its polycrystalline nature is not detrimental to the optical switching performance of the material, since the least dispersive direction of the band structure dominates the contribution to the optical response, which favors low-cost fabrication. Together with the outstanding photophysical properties of MAPbI3, this finding highlights the great potential of this material in ultrafast light modulation and novel photonic applications. AU - Berghoff, Daniel AU - Bühler, Johannes AU - Bonn, Mischa AU - Leitenstorfer, Alfred AU - Meier, Torsten AU - Kim, Heejae ID - 37338 IS - 1 JF - Nature Communications KW - General Physics and Astronomy KW - General Biochemistry KW - Genetics and Molecular Biology KW - General Chemistry KW - Multidisciplinary SN - 2041-1723 TI - Low-field onset of Wannier-Stark localization in a polycrystalline hybrid organic inorganic perovskite VL - 12 ER - TY - JOUR AU - Thong, Le Huu AU - Ngo, Cong AU - Duc, Huynh Thanh AU - Song, Xiaohong AU - Meier, Torsten ID - 23477 JF - Physical Review B SN - 2469-9950 TI - Microscopic analysis of high harmonic generation in semiconductors with degenerate bands VL - 103 ER - TY - JOUR AB - Lithium niobate (LiNbO3), a material frequently used in optical applications, hosts different kinds of polarons that significantly affect many of its physical properties. In this study, a variety of electron polarons, namely free, bound, and bipolarons, are analyzed using first-principles calculations. We perform a full structural optimization based on density-functional theory for selected intrinsic defects with special attention to the role of symmetry-breaking distortions that lower the total energy. The cations hosting the various polarons relax to a different degree, with a larger relaxation corresponding to a larger gap between the defect level and the conduction-band edge. The projected density of states reveals that the polaron states are formerly empty Nb 4d states lowered into the band gap. Optical absorption spectra are derived within the independent-particle approximation, corrected by the GW approximation that yields a wider band gap and by including excitonic effects within the Bethe-Salpeter equation. Comparing the calculated spectra with the density of states, we find that the defect peak observed in the optical absorption stems from transitions between the defect level and a continuum of empty Nb 4d states. Signatures of polarons are further analyzed in the reflectivity and other experimentally measurable optical coefficients. AU - Schmidt, Falko AU - Kozub, Agnieszka L. AU - Gerstmann, Uwe AU - Schmidt, Wolf Gero AU - Schindlmayr, Arno ID - 21946 JF - Crystals TI - Electron polarons in lithium niobate: Charge localization, lattice deformation, and optical response VL - 11 ER - TY - CONF AB - Population/mixing-time-dependent two-dimensional coherent spectra are presented for exciton-polaritons in a microcavity. Theory based on dynamically-controlled truncation reveals coherent and incoherent contributions to the decay dynamics. AU - Meier, Torsten AU - Paul, Jagannath AU - Rose, Hendrik AU - Wahlstrand, Jared K AU - Bristow, Alan D ID - 43746 SN - 978-1-55752-308-2 T2 - Frontiers in Optics TI - Coherent and incoherent contribution of population dynamics of semiconductor exciton-polaritons ER - TY - CONF AU - Reichelt, Matthias AU - Rose, Hendrik AU - Kosarev, Alexander N. AU - Poltavtsev, Sergey V. AU - Bayer, Manfred AU - Akimov, Ilya A. AU - Schneider, Christian AU - Kamp, Martin AU - Höfling, Sven AU - Meier, Torsten ED - Betz, Markus ED - Elezzabi, Abdulhakem Y. ID - 23474 T2 - Ultrafast Phenomena and Nanophotonics XXV TI - Controlling the emission time of photon echoes by optical freezing of exciton dephasing and rephasing in quantum-dot ensembles VL - 11684 ER - TY - JOUR AU - Murzakhanov, F. F. AU - Yavkin, B. V. AU - Mamin, G. V. AU - Orlinskii, S. B. AU - von Bardeleben, H. J. AU - Biktagirov, Timur AU - Gerstmann, Uwe AU - Soltamov, V. A. ID - 29749 JF - Physical Review B SN - 2469-9950 TI - Hyperfine and nuclear quadrupole splitting of the NV− ground state in 4H-SiC VL - 103 ER - TY - JOUR AU - Aldahhak, Hazem AU - Hogan, Conor AU - Lindner, Susi AU - Appelfeller, Stephan AU - Eisele, Holger AU - Schmidt, Wolf Gero AU - Dähne, Mario AU - Gerstmann, Uwe AU - Franz, Martin ID - 22010 JF - Physical Review B SN - 2469-9950 TI - Electronic structure of the Si(111)3×3R30∘−B surface from theory and photoemission spectroscopy VL - 103 ER - TY - JOUR AU - Rose, Hendrik AU - Popolitova, D. V. AU - Tikhonova, O. V. AU - Meier, Torsten AU - Sharapova, Polina ID - 23478 JF - Physical Review A SN - 2469-9926 TI - Dark-state and loss-induced phenomena in the quantum-optical regime of Λ-type three-level systems VL - 103 ER - TY - JOUR AU - Belobo, Didier Belobo AU - Meier, Torsten ID - 23473 JF - New Journal of Physics SN - 1367-2630 TI - Approximate nonlinear wave solutions of the coupled two-component Gross–Pitaevskii equations with spin–orbit interaction VL - 23 ER - TY - JOUR AU - Nguyen, T. T. Nhung AU - Sollfrank, T. AU - Tegenkamp, C. AU - Rauls, E. AU - Gerstmann, Uwe ID - 22881 JF - Physical Review B SN - 2469-9950 TI - Impact of screening and relaxation on weakly coupled two-dimensional heterostructures VL - 103 ER - TY - JOUR AB - Modern forming processes often allow today the efficient production of complex parts. In order to increase the sustainability of forming processes it would be favorable if the forming of workpieces becomes possible using production waste. At the Chair of Forming and Machining Technology of the Paderborn University (LUF) research is presently conducted with the overall goal to produce workpieces directly from secondary aluminum (e.g., powder and chips). Therefore, friction-based forming processes like friction spinning (or cognate processes) are used due to their high efficiency. As a pre-step, the production of semi-finished parts was the subject of accorded research work at the LUF. Therefore, a friction-based hot extrusion process was used for the full recycling or rework of aluminum chips into profiles. Investigations of the recycled semi-finished products show that they are comparable to conventionally produced semi-finished products in terms of dimensional stability and shape accuracy. An analysis of the mechanical properties of hardness and tensile strength shows that a final product with good and homogeneously distributed properties can be produced. Furthermore, significant correlations to the friction spinning process could be found that are useful for the above-mentioned direct part production from secondary aluminum. AU - Borgert, Thomas AU - Homberg, Werner ID - 21635 JF - Metals SN - 2075-4701 TI - Friction-Induced Recycling Process for User-Specific Semi-Finished Product Production ER - TY - CONF AU - Moritzer, Elmar AU - Flachmann, Felix ID - 23746 SN - 978-1-7138-3075-7 T2 - SPE ANTEC 2021: The Annual Technical Conference for Plastic Professionals TI - Influence of Chemical Blowing Agents on the Filling Behavior of Wood-Plastic-Composite Melts ER - TY - JOUR AU - Bolenz, Lukas AU - Ehlert, Thomas AU - Dechert, Christopher AU - Bertling, René AU - Kenig, Eugeny ID - 23789 JF - Chemical Engineering Research and Design SN - 0263-8762 TI - Modelling of a continuous distillation process with finite reflux ratio using the hydrodynamic analogy approach ER - TY - CONF AB - Driven by the CO2-emission law by the European government and the increasing costs for raw materials as well as energy, the automotive industry is increasingly using multi-material constructions. This leads to a continuous increase in the use of mechanical joining techniques and especially the self-piercing riveting is of particular importance. The reason for this is the wide range of joining possibilities as well as the high load-bearing capacities of the joints. To be able to react to changing boundary conditions, like material thickness or strength variation of the sheets, research work is crucial with regard to the increase of versatility. In this paper, a numerical study of the influences on the selfpiercing riveting process is presented. For this purpose, the influence of different process parameters such as rivet length and die depth on various quality-relevant characteristics were investigated. With the help of the design of experiment, significant influences were determined and interactions between the individual parameters are shown. AU - Kappe, Fabian AU - Bielak, Christian Roman AU - Sartisson, Vadim AU - Bobbert, Mathias AU - Meschut, Gerson ID - 34222 T2 - ESAFORM 2021 TI - Influence of rivet length on joint formation on self-piercing riveting process considering further process parameters ER - TY - CONF AB - In many areas of product manufacturing constructions consist of individual components and metal sheets that are joined together to form complex structures. A simple and industrial common method for joining dissimilar and coated materials is clinching. During the joining process and due to the service load cracks can occur in the area of the joint, propagate due to cyclic loading and consequently lead to structural failure. For the prevention of these damage cases, first of all knowledge about the fracture mechanical material parameters regarding the original material state of the sheet metals used within the clinching process are essential.Within the scope of this paper experimental and numerical preliminary investigations regarding the fracture mechanical behavior of sheet metals used within the clinching process are presented. Due to the low thickness of 1.5 mm of the material sheets, the development of a new specimen is necessary to determine the crack growth rate curve including the fracture mechanical parameters like the threshold against crack growth ΔKI,th and the fracture toughness KIC of the base material HCT590X. For the experimental determination of the crack growth rate curve the numerical calculation of the geometry factor function as well as the calibration function of this special specimen are essential. After the experimental validation of the numerically determined calibration function, crack growth rate curves are determined for the stress ratios R = 0.1 and R = 0.3 to examine the mean stress sensitivity. In addition, the different rolling directions of 0° and 90° in relation to the initial crack are taken into account in order to investigate the influence of the anisotropy due to rolling. AU - Weiß, Deborah AU - Schramm, Britta AU - Kullmer, Gunter ID - 30675 KW - Mechanical Engineering KW - Mechanics of Materials KW - General Materials Science SN - 1662-9795 T2 - Key Engineering Materials TI - Numerical and Experimental Fracture Mechanical Investigations of Clinchable Sheet Metals Made of HCT590X VL - 883 ER - TY - JOUR AB - AbstractIn addition to the classical strength calculation, it is important to design components with regard to fracture mechanics because defects and cracks in a component can drastically influence its strength or fatigue behavior. Cracks can propagate due to operational loads and consequently lead to component failure. The fracture mechanical analysis provides information on stable or unstable crack growth as well as about the direction and the growth rate of a crack. For this purpose, sufficient information has to be available about the crack location, the crack length, the component geometry, the component loading and the fracture mechanical material parameters. The fracture mechanical properties are determined experimentally with standardized specimens as defined by the guidelines of the American Society for Testing and Materials. In practice, however, especially in the context with damage cases or formed material fracture mechanical parameters directly for a component are of interest. However, standard specimens often cannot be extracted at all due to the complexity of the component geometry. Therefore, the development of special specimens is required whereby certain arrangements have to be made in advance. These arrangements are presented in the present paper in order to contribute to a holistic investigation chain for the experimental determination of fracture mechanical material parameters with special specimens. AU - Weiß, Deborah AU - Schramm, Britta AU - Kullmer, Gunter ID - 30674 JF - Production Engineering KW - Industrial and Manufacturing Engineering KW - Mechanical Engineering SN - 0944-6524 TI - Holistic investigation chain for the experimental determination of fracture mechanical material parameters with special specimens ER - TY - JOUR AB - Powder X-ray diffraction (XRD) patterns of ordered mesoporous CMK-8 and CMK-9 carbon materials are simulated by geometric modeling. The materials are amorphous at the atomic length scale but exhibit highly symmetric gyroidal structures at the nanometer scale, corresponding to regular, continuous nanopore systems with cubic symmetry. Their structures lead to characteristic low-angle XRD signatures. We introduce a model based on geometrical considerations to simulate CMK-8 and CMK-9 structures with variable volume fraction of carbon (vs. pore volume, i.e., variable 'pore wall thickness'). In addition, we also simulate carbon materials with variable amounts of guest species (e.g., sulfur) residing in their pores. The corresponding XRD patterns are calculated. The carbon volume fraction turns out to have a significant impact on the relative diffraction peak intensities, especially in case of CMK-9 carbon that features a bimodal porosity. Likewise, the presence of guest species in the pores may also strongly affect the relative peak intensities. Our study suggests that careful evaluation of experimental low-angle XRD patterns of (real) CMK-8 or CMK-9 materials offers an opportunity to obtain detailed information about the nanostructural properties in addition to the mere identification of the pore systems geometry. AU - Schwind, Bertram AU - Smått, Jan-Henrik AU - Tiemann, Michael AU - Weinberger, Christian ID - 25894 JF - Microporous and Mesoporous Materials SN - 1387-1811 TI - Modeling of gyroidal mesoporous CMK-8 and CMK-9 carbon nanostructures and their X-Ray diffraction patterns ER - TY - JOUR AB - A comparison of infrared spectroscopic analytical approaches was made in order to assess their applicability for internal structure characterization of SiO2 thin films. Markers for porosity and/or disorder based on the analysis of the asymmetric stretching absorption band of SiO2 between 900−1350 cm−1 were discussed. The shape of this band, which shows a well-defined LO–TO splitting, depends not only on the inherent characteristics of the film under analysis but also on the particular geometry of the IR experiment and the specific surface selection rules of the substrate. Three types of SiO2 thin films with clearly defined porosity ranging from dense films to mesoporous films were investigated by transmission (at different incidence angles), direct specular reflection (at different angles), and diffuse reflection. Two different types of substrate, metallic and semiconducting, were used. The combined effect of substrate and specific technique in the final shape of the band, was discussed, and the efficacy for their applicability to the determination of porosity in thin SiO2 films was critically evaluated. AU - de los Arcos, Teresa AU - Müller, Hendrik AU - Wang, Fuzeng AU - Damerla, Varun Raj AU - Hoppe, Christian AU - Weinberger, Christian AU - Tiemann, Michael AU - Grundmeier, Guido ID - 25897 JF - Vibrational Spectroscopy SN - 0924-2031 TI - Review of infrared spectroscopy techniques for the determination of internal structure in thin SiO2 films ER - TY - THES AU - Olenberg, Alexander ID - 42812 SN - 9783843947855 TI - Untersuchung und Optimierung von strukturierten Packungen mittels CFD-Simulationen ER - TY - JOUR AB - Tailor-made ordered mesoporous materials bear great potential in numerous fields of application where large interfaces are required. However, the inherent surfacechemical properties of conventional materials, such as silica, carbon or organosilica, poses some limitations with respect to their application. Surface manipulation by functionalization with chemically more reactive groups is one way to improve materials for their desired purpose. Another approach is the design of high surface-area composite materials. The surface manipulation, either by functionalization or by introducing guest species, can be performed selectively. This means that when several distinct, i.e. , hierarchical, types of surfaces or pore systems exist in a material, each of them may be chosen for manipulation. Several strategies can be identified to achieve this goal. Molecules or molecule assemblies can be utilized to temporarily protect pores or surfaces (soft protection), while manipulation occurs at the accessible sites. This approach is a recurring motive in this review and can also be applied to rigid template matrices (hard protection). Furthermore, the size of functionalization agents (size protection) and their reactivity/diffusion (kinetic protection) into the pores can also be utilized to achieve selectivity. In addition, challenges in the synthesis and characterization of selectively manipulated ordered mesoporous materials are discussed. AU - Tiemann, Michael AU - Weinberger, Christian ID - 25893 JF - Advanced Materials Interfaces SN - 2196-7350 TI - Selective Modification of Hierarchical Pores and Surfaces in Nanoporous Materials ER - TY - JOUR AU - Fuchs, Christian ID - 41431 IS - 1 JF - tripleC: Communication, Capitalism & Critique TI - Engels@200: Friedrich Engels in the Age of Digital Capitalism VL - 19 ER - TY - JOUR AU - Fuchs, Christian AU - Dyer-Witheford, Nick ID - 41599 JF - 国际社会科学杂志 (Journal of International Social Sciences) 2021 (9) TI - 卡尔·马克思与互联网研究 ER -