@article{StollenwerkDoehringFreudenmannetal.2021, author = {Stollenwerk, Manfred and D{\"o}hring, Thorsten and Freudenmann, Dominic and Sch{\"a}fer, Tobias and Stadtm{\"u}ller, Johannes and R{\"o}cke, Nicole}, title = {Sputtered highly effective iridium catalysts: a new approach for green satellite propulsion}, series = {Journal of Materials Science}, volume = {2021}, journal = {Journal of Materials Science}, number = {2021}, doi = {https://doi.org/10.1007/s10853-021-05897-z}, pages = {1 -- 11}, year = {2021}, abstract = {This work demonstrated the large potential of sputtered iridium metal for catalytic reactions shown by the example of decomposition of hydrogen peroxide (H2O2) for space propulsion systems. For this purpose, iridium was coated onto Al2O3 pellets by a sputter process under varied process parameters. Depending on previously selected parameters, the obtained metal-loaded pellets offer closed- and/or open-shell structures. Catalytic productivity of these first-generation iridium-sputtered catalysts was estimated in laboratory experiments and compared to platinum-loaded pellets. Under optimized sputter-process conditions, the reactivity is significantly improved compared to the platinum-impregnated pellets. The better catalytic productivity can be explained by the increased active surface area of the iridium layers on the pellets. The surface morphology and the microstructure of the iridium coating can be actively controlled by the sputter pressure. The results are in accordance with the sputtering process pressure tendency described by the Thornton Structure-Zone Model.}, subject = {Iridium}, language = {en} } @inproceedings{DoehringStritzelbergerMuesetal.2021, author = {D{\"o}hring, Thorsten and Stritzelberger, Carolyn and Mues, Kristin and Sch{\"a}fer, Kerstin and Rosendahl, Wilfried and Busch, Uwe}, title = {Celebrating the R{\"o}ntgen anniversary year: pupil experiments at Aschaffenburg University}, series = {SPIE Proceedings}, volume = {2021}, booktitle = {SPIE Proceedings}, number = {11776}, publisher = {SPIE}, organization = {TH Aschaffenburg}, doi = {https://doi.org/10.1117/12.2589142}, pages = {117760E-1 -- 117760E-10}, year = {2021}, abstract = {On November 8th, 1895, Professor Wilhelm Conrad R{\"o}ntgen was still working late on cathode rays in his laboratory at the University of W{\"u}rzburg in Germany. By chance, he found a new type of radiation that was able to penetrate materials. He himself called them X-rays. In his honour, in Germany we call this type of radiation R{\"o}ntgen´s rays since 1896. In 2020, Germany was celebrating the R{\"o}ntgen anniversary year, recognizing the discovery of X-rays 125 years ago and the 175th birthday of its discoverer Wilhelm Conrad R{\"o}ntgen, the first Nobel laureate in physics. Financed by a grant from the Klaus Tschira Foundation, the Reiss-Engelhorn-Museums in Mannheim and the German R{\"o}ntgen Museum in Remscheid developed an "X-periments mobile" with interactive experiments for children and young people. Following the given motto "X-periments - making the invisible visible", this research station with optical experiments started traveling across Germany in the anniversary year and, due to the corona pandemic in the following year. In summer 2021, the "X-periments mobile" will make a guest appearance at Aschaffenburg University. The experimental set-ups enable school classes and students to gain an overview of optical technologies from infrared light to ultraviolet radiation to X-rays and gamma rays. The aim of the campaign is to inspire the young generation and to attract students for courses in science and technology. This contribution presents the historical discovery of X-rays, the "X-periments mobile" and its experiments, its intention, and the experiences from its stays at different places across Germany.}, subject = {R{\"o}ntgen, Wilhelm Conrad, 1845-1923}, language = {en} } @misc{DoehringStollenwerkStadtmuelleretal.2021, author = {D{\"o}hring, Thorsten and Stollenwerk, Manfred and Stadtm{\"u}ller, Johannes and Freudenmann, Dominic and R{\"o}cke, Nicole}, title = {Nanostructured iridium catalysts for effective hydrogen peroxide decomposition}, series = {EuroNanoForum}, volume = {2021}, journal = {EuroNanoForum}, organization = {TH Aschaffenburg}, pages = {1}, year = {2021}, abstract = {The EU intends to restrict the use of critical fuels in space propulsion systems. These propellants like hydrazine are chemically aggressive, toxic and carcinogenic. Space propulsion of the future should be environmentally friendly, inexpensive, and easy to handle. Aschaffenburg University and DLR are currently developing environmentally friendly technologies for future satellite engines. Thereby rocket-grade hydrogen peroxide, which is foreseen as a substitute, is converted to uncritical water vapour and oxygen by an exothermic catalytic reaction on nanostructured iridium layers. The resulting hot gases provide the required amount of thrust. The iridium catalyst layers are coated onto ceramic pellets, using RF magnetron sputtering technology. The catalytic functionality was tested afterwards at the chemical laboratories of DLR. First experimental results show a significantly higher catalytic activity for nanostructured iridium surfaces than for smoother crystalline layers.}, subject = {Iridium}, language = {en} } @misc{Doehring2021, author = {D{\"o}hring, Thorsten}, title = {Advanced Materials and Manufacturing Technologies for Space Applications}, series = {Proceedings of International Research Days}, volume = {2021}, journal = {Proceedings of International Research Days}, organization = {TH Aschaffenburg}, pages = {1}, year = {2021}, abstract = {The goal of this project is to develop satellite components for space-based astronomical satellite payloads. Thereby advanced materials like iridium and innovative manufacturing technologies will be applied. After environmental testing and space qualifications tests it is planned to do an astronomical experiment with a stratospheric balloon or a sounding rocket. The work is embedded in ACCASI („Aschaffenburg Competence Center for Astronomical and Space Instumentation")}, subject = {Satellitentechnik}, language = {en} } @misc{GiovanniDoehringValsecchietal.2019, author = {Giovanni, Pareschi and D{\"o}hring, Thorsten and Valsecchi, Guiseppe and Magagnin, Luca and Bradshaw, Miranda and Burwitz, Vadim and Civitani, Marta Maria and Cotroneo, Vincenzo and Gibertini, Eugenio and Pelliciari, Carlo and Sironi, Giorgia and Yang, Yang}, title = {Enhancing the ATHENA effective area at low x-ray energies with unconventional overcoatings}, series = {Proceedings of the X-RAY ASTRONOMY 2019 conference}, volume = {2019}, journal = {Proceedings of the X-RAY ASTRONOMY 2019 conference}, organization = {Istituto Nazionale di Astrofisica}, pages = {1 -- 1}, year = {2019}, abstract = {Low density overcoatings (mainly based on materials containing Carbon) onto usual hi Z materials (like Ir, Au or Pt) have been proposed more than 10 years ago for enhancing the X-ray reflectivity at low energy (between 0.5 and 4 keV) in X-ray astronomical optics. The hack is to use the total reflection from the low density material (which do not suffer much the photoelectric absorption) at low energy, while the photons at high energy are reflected by the high density material. Now for several future projects like e.g. ATHENA and eXTP it is foreseen the use of low density overcoatings that will importantly increase the effective area at low energy. In this poster we will discuss about the use of materials different from the ones considered so far, in particular based on a thin layer of Chromium followed by another layer of a Carbon-like material, and of novel approaches for their application.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @article{Doehring2021, author = {D{\"o}hring, Thorsten}, title = {Forscher entwickeln umweltfreundliche Satellitenantriebe}, series = {Wirtschaft am Bayerischen Untermain}, volume = {2021}, journal = {Wirtschaft am Bayerischen Untermain}, number = {M{\"a}rz}, editor = {IHK Aschaffenburg,}, pages = {12 -- 13}, year = {2021}, abstract = {In der aktuellen F{\"o}rderrunde des vom Bayerischen Staatsministeriums f{\"u}r Wissenschaft und Kunst aufgesetzten „Programms zur F{\"o}rderung der angewandten Forschung und Entwicklung an Hochschulen f{\"u}r angewandte Wissenschaften - Fachhochschulen" war die Technische Hochschule Aschaffenburg sehr erfolgreich. F{\"u}r das Technologieprojekt ACCASI („Aschaffenburg Competence Center for Astronomical and Space Instrumentation") erh{\"a}lt sie {\"u}ber eine Laufzeit von drei Jahren insgesamt 250.000 Euro.}, subject = {Satellitentechnik}, language = {de} } @inproceedings{KaetkerSchreiberBuschetal.2023, author = {K{\"a}tker, Anna and Schreiber, Kai and Busch, Uwe and Stanik, Eva and D{\"o}hring, Thorsten}, title = {Unsichtbares erkunden - Experimente im Museumslabor R{\"o}Lab des Deutschen R{\"o}ntgen-Museums}, volume = {2023}, number = {124}, publisher = {DGaO Proceedings}, organization = {Deutsches R{\"o}ntgen-Museum}, issn = {1614-8436}, pages = {1 -- 2}, year = {2023}, abstract = {Das R{\"o}Lab versteht sich als ein {\"u}berregionales, außerschulisches Bildungsangebot, das Begeisterung f{\"u}r Natur- und Ingenieurwissenschaften, Medizin und Medizintechnik an unterschiedliche Zielgruppen vermittelt und damit einen Beitrag zur Allgemeinbildung und MINT-F{\"o}rderung leistet. Das didaktische Konzept nimmt den „Hands-on-Science" Gedanken stringent auf, weckt den Forschergeist und erm{\"o}glicht es den Lernenden, Unsichtbares zu erkunden.}, subject = {R{\"o}ntgen, Wilhelm Conrad, 1845-1923}, language = {de} } @inproceedings{HudecPomahačStaniketal.2023, author = {Hudec, Rene and Pomahač, Vit and Stanik, Eva and D{\"o}hring, Thorsten and Schilling, Klaus}, title = {Space Telescopes based on Satellite Tandem Flights}, series = {DGaO Proceedings}, volume = {2023}, booktitle = {DGaO Proceedings}, issn = {1614-8436}, pages = {2}, year = {2023}, abstract = {Progress in satellite control engineering enables tandem flight arrangements of mini-satellites in future space missions. Cost effective CubeSat technologies offer an interesting possibility for space-born telescope payloads. Two small satellites will carry the telescope optics and the detector system, respectively. Related formation flight requirements could be transferred from the NetSat-Mission.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @misc{StanikDoehringSchreiberetal.2022, author = {Stanik, Eva and D{\"o}hring, Thorsten and Schreiber, Kai and K{\"a}tker, Anna and Busch, Uwe}, title = {X-ray honour gallery - award winners of the R{\"o}ntgen Medal}, organization = {TH Aschaffenburg}, pages = {1}, year = {2022}, abstract = {Starting in 1951, on the 50th anniversary of the award of the first Nobel Prize for physics to Wilhelm Conrad R{\"o}ntgen, the Lord Mayor of the German city of Remscheid has annually awarded R{\"o}ntgen Medals to scientists who "in the broadest sense have made a special contribution to the progress and dissemination of X-ray discoveries in the theoretical and applied sciences". The R{\"o}ntgen Medal has become highly recognized in the scientific world. To date, more than one hundred scientists have received this honour. Through their chronology, this contribution presents a "Who's Who" of X-ray science and provides selected insights into their scientific work; with special focus on the fields of X-ray optics and X-ray astronomy.}, subject = {R{\"o}ntgen, Wilhelm Conrad, 1845-1923}, language = {en} } @misc{SchreiberKaetkerBuschetal.2022, author = {Schreiber, Kai and K{\"a}tker, Anna and Busch, Uwe and Stanik, Eva and D{\"o}hring, Thorsten}, title = {Insights into the history of X-rays: the Deutsches R{\"o}ntgen-Museum in Remscheid}, organization = {Deutsches R{\"o}ntgen-Museum}, pages = {1}, year = {2022}, abstract = {In 1895, Professor Wilhelm Conrad R{\"o}ntgen detected a new kind of radiation that was able to penetrate solid materials, which he called x-rays. In 1901 R{\"o}ntgen received the first Nobel Prize in physics in honour of this ground breaking discovery. The Deutsches R{\"o}ntgen-Museum in Remscheid in Germany is the institution that uniquely and comprehensively explores and documents the life and work of W. C. R{\"o}ntgen and the impact of his discovery. The museum's location in Remscheid is not coincidental, with R{\"o}ntgen's birthplace only a short walk away from its exhibits. Every visit to the museum amounts to a unique expedition through the worlds of medicine, science, and technology. The museum's emphasis on the diversity of R{\"o}ntgen's invention by a multilingual, multi-medial approach enables all visitors to make their own personal discoveries. The Deutsches R{\"o}ntgen-Museum in Remscheid is a mustsee for x-ray scientists from anywhere in the world. This contribution provides an insight into the history of x-rays and offers a guided tour of the Deutsches R{\"o}ntgen-Museum and its exhibits.}, subject = {R{\"o}ntgen, Wilhelm Conrad, 1845-1923}, language = {en} }