TY - JOUR A1 - Helbig, Uta A1 - Herbst, Kai A1 - Roudenko, Jewgeni A1 - Helbig, Jens A1 - Barton, Bastian A1 - Kolb, Ute T1 - Carbon-doped titania as a precursor for titanate nanotubes JF - Journal of Materials Research N2 - Carbon-doped titania was fabricated via carbothermal treatment in nitrogen–acetylene gas flow and further used as a precursor for multiwalled titanate nanotube (TNT) synthesis via alkaline hydrothermal route. Investigation of the reaction products after hydrothermal treatment of carbon-doped titania using Transmission electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller method shows the successful formation of TNTs. The presence of carbon was proved although the type of incorporation could not be certified. All samples show approximately the same carbon content before and after hydrothermal treatment. An increasing pretreatment temperature of titania precursor powders yields more secondary products in the nanotube samples, indicating lower reactivity of the titanium oxycarbide phase during hydrothermal treatment. In this study, TNTs with 6 wt% carbon and with the highest specific surface area of 340 m2/g were formed via hydrothermal treatment of carbon-doped titania precursor powder exposed to 700 °C during carbothermal pretreatment. Y1 - 2018 U6 - https://doi.org/10.1557/jmr.2018.49 SN - 0884-2914 VL - 33 IS - 9 SP - 1288 EP - 1300 PB - Springer Science and Business Media LLC ER - TY - CHAP A1 - Wägemann, Tobias A1 - Werner, Albert T1 - Generating Multi-objective Programs from Variant-rich EAST-ADL Product Line Architectures T2 - INFORMATIK 2015 N2 - The design of robust architectures for software-intensive systems in the automotive domain is a complex task and a considerable engineering challenge. Even conventional systems are usually subject to a multitude of conflicting design goals, such as unit cost and weight minimization, dependability augmentation and timing control. One feasible approach to resolve these conflicting levers on a system's architecture is to perform an optimization analysis on a concretely defined design space, which in general is vast. For the purpose of the approach presented here, this design space is represented by an automated identification of variation points relevant for design space exploration. The identified variability information is then transformed into a convenient mathematical representation for product-line-aware architecture optimization. KW - Model-based Analysis KW - Multi-objective Programming KW - Architecture Optimization KW - Pareto Optimality KW - Product Line Engineering Y1 - 2015 SN - 978-3-88579-640-4 SN - 1617-5468 SP - 1673 EP - 1685 PB - Gesellschaft für Informatik e.V.. CY - Bonn ER - TY - CHAP A1 - Zoppelt, Markus A1 - Tavakoli Kolagari, Ramin T1 - What Today's Serious Cyber Attacks on Cars Tell Us BT - Consequences for Automotive Security and Dependability T2 - Model-Based Safety and Assessment : 6th International Symposium, IMBSA 2019, Thessaloniki, Greece, October 16–18, 2019, Proceedings N2 - Highly connected with the environment via various interfaces, cars have been the focus of malicious cyber attacks for years. These attacks are becoming an increasing burden for a society with growing vehicle autonomization: they are the sword of Damocles of future mobility. Therefore, research is particularly active in the area of vehicle IT security, and in part also in the area of dependability, in order to develop effective countermeasures and to maintain a minimum of one step ahead of hackers. This paper examines the known state-of-the-art security and dependability measures based on a detailed and systematic analysis of published cyber attacks on automotive software systems. The sobering result of the analysis of the cyber attacks with the model-based technique SAM (Security Abstraction Model) and a categorization of the examined attacks in relation to the known security and dependability measures is that most countermeasures against cyber attacks are hardly effective. They either are not applicable to the underlying problem or take effect too late; the intruder has already gained access to a substantial part of the vehicle when the countermeasures apply. The paper is thus contributing to an understanding of the gaps that exist today in the area of vehicle security and dependability and concludes concrete research challenges. KW - Automotive Security KW - Automotive System Architecture KW - Dependability KW - Model-Driven Engineering Methodologies Y1 - 2019 SN - 978-3-030-32872-6 U6 - https://doi.org/10.1007/978-3-030-32872-6_18 SP - 219 EP - 285 PB - Springer CY - Cham ER - TY - JOUR A1 - Seiß, Volker A1 - Helbig, Uta A1 - Lösel, Ralf A1 - Eichelbaum, Maik T1 - Investigating and correlating photoelectrochemical, photocatalytic, and antimicrobial properties of TiO2 nanolayers JF - Scientific Reports N2 - Semiconducting transition metal oxides such as TiO 2 are promising photo(electro)catalysts for solar water splitting and photoreduction of CO 2 as well as for antibacterial, self-, water and air-cleaning coatings and admixtures in paints, building materials, on window glass or medical devices. In photoelectrocatalytic applications TiO 2 is usually used as photoanode only catalyzing the oxidation reaction. In coatings and admixtures TiO 2 works as heterogeneous catalyst and has to catalyze a complete redox cycle. While photoelectrochemical charge transport parameters are usually quite well accessible by electrochemical measurements, the quantitative description of photocatalytic properties is more challenging. Here, we present a systematic structural, photoelectrocatalytic, photocatalytic and antimicrobial study to understand if and how photoelectrochemical parameters can be used to predict the photocatalytic activity of TiO 2. For this purpose TiO 2 thin films on flourine-doped tin oxide substrates were prepared and annealed at temperatures between 200 and 600 ◦C. The film morphologies and thicknesses were studied by GIXRD, FESEM, and EDX. Photoelectrochemical properties were measured by linear sweep voltammetry, photoelectrochemical impedance spectroscopy, chopped light chronoamperometry, and intensity modulated photocurrent/photovoltage spectroscopy. For comparison, photocatalytic rate constants were determined by methylene blue degradation and Escherichea coli inactivation and correlated with the deducedphotoelectrocatalytic parameters. We found that the respective photoactivities of amorphous and crystalline TiO 2 nanolayers can be best correlated, if the extracted photoelectrochemical parameters such as charge transfer and recombination rates, charge transfer efficiencies and resistances are measured close to the open circuit potential (OCP). Hence, the interfacial charge transport parameters at the OCP can be indeed used as descriptors for predicting and understanding the photocatalytic activity of TiO 2 coatings. KW - Multidisciplinary Y1 - 2021 U6 - https://doi.org/10.1038/s41598-021-01165-x SN - 2045-2322 VL - 11 SP - 1 EP - 16 PB - Springer Science and Business Media LLC ER -