TY - JOUR A1 - Melekhov, Evgeny A1 - Penn, Tatjana A1 - Weidauer, Tobias A1 - Abb, Valerius A1 - Kammler, Martin A1 - Lechner, Alfred T1 - Tunable nanopillar array on a quartz-fiber tip for surface enhanced Raman scattering (SERS) detection JF - tm - Technisches Messen N2 - In this work, a simple two-step method to create tunable self-assembled three-dimensional nanostructure array-like nanoantennas directly on the tip of an optical quartz glass fiber is described. The structures are prepared by using dry etching of the fiber tip. For the etching process, gold nanoparticles fabricated by thermal dewetting technique were used as template. The structures are applied as sensors for label-free analysis of organic substances in ppb range, such as drug residues in liquid solutions. The measurements are carried out by a portable Raman device with an exchangeable sensor head utilizing the SERS-effect. This method allows in situ applications. In order to characterize the SERS cells, para-thiocresol and diclofenac sodium are used as model substances. For optimization of the substrate performance, different thicknesses of the dewetting-layer (6, 9, 12 nm), different etching times for formation of the pillars (6, 8, 10 and 12 min), and different thicknesses of SERS-metallization (25, 50, 75 nm) of gold and silver are compared. In order to show the applicability of the structure on the tip of a fiber, measurements from the upper side and from the underside of the substrate on quartz plates are compared. Reproducible SERS enhancement factors up to 10 7 {10^{7}} were achieved. N2 - In dieser Arbeit wird eine zweistufige Methode beschrieben, um einstellbare selbstorganisierte dreidimensionale SERS-aktive Nanostrukturen in Form von Nanosäulen auf der Spitze einer optischen Quarzglasfaser herzustellen. Die Strukturen werden durch trockenchemisches Ätzen der Faserspitze erzeugt. Für den Ätzprozess werden als Maske Goldnanopartikel verwendet, die mittels Thermal Dewetting hergestellt werden. Der Sensor wird für eine markierungsfreie Analyse von organischen Substanzen, wie bspw. Medikamentenrückstände in wässrigen Lösungen, im ppb-Bereich eingesetzt. Die Messungen werden mit einem tragbaren Raman-Gerät mit einem austauschbaren Sensorkopf durchgeführt. Um die SERS-Zellen zu charakterisieren, werden para-Thiocresol und Diclofenac-Natrium als Modellsubstanzen verwendet. Zur Optimierung der Substratleistung werden unterschiedliche Dicken der Dewettinglayer (6, 9, 12 nm), unterschiedliche Ätzzeiten der Nanosäulen (6, 8, 10 und 12 min) und unterschiedliche Schichtdicken der SERS-Metallisierung (25, 50, 75 nm) von Gold und Silber verglichen. Um die Anwendbarkeit der Struktur an der Spitze einer Faser zu zeigen, werden Messungen von der Oberseite und von der Rückseite des Substrats in Form eines Quarzglasplatten verglichen. Diese Struktur liefert einen reproduzierbaren Verstärkungsfaktor von bis zu 107. T2 - Einstellbare Nanosäulenanordnung auf der Spitze einer Quarzglasfaser für oberflächenverstärkte Raman-Spektroskopie (SERS) Y1 - 2022 U6 - https://doi.org/10.1515/teme-2021-0093 VL - 89 IS - 1 SP - 70 EP - 81 PB - de Gruyter ER - TY - JOUR A1 - Kammler, Martin A1 - Chidambarrao, D. A1 - Schwarz, K. W. A1 - Black, C. T. A1 - Ross, Frances M. T1 - Controlled nucleation of dislocations by a spatially localized stress field JF - Applied Physics Letters N2 - We analyze the nucleation of dislocations in silicon at spatially localized stress fields generated by silicon nitride pads having a high intrinsic stress. The nucleation and final configuration of the dislocations were studied using hot-stage transmission electron microscopy and were compared with dislocation simulations based on calculations of the stress fields around the pads. We find that the simulated configurations match well with the experimental data, and we show that the dislocation configuration can be controlled by the pad size. Y1 - 2005 U6 - https://doi.org/10.1063/1.2061862 VL - 87 IS - 13 PB - AIP ER - TY - JOUR A1 - Kammler, Martin A1 - Horn-von Hoegen, Michael T1 - Transition in growth mode by competing strain relaxation mechanisms BT - surfactant mediated epitaxy of SiGe alloys on Si JF - Applied Physics Letters N2 - Surfactant mediated epitaxy of Si(1−x)Gex alloys on Si(111) can, besides technological importance, clarify the influence of the lattice mismatch during surfactant mediated heteroepitaxial growth. For low Ge concentration we find an immediate layer-by-layer growth, whereas at high Ge concentration a roughening transition followed by relaxation of the lattice mismatch in a periodic dislocation network is preferred. This behavior can be explained by comparing the dislocation nucleation rate on a smooth surface with the island nucleation rate on a pseudomorphic film. Y1 - 2004 U6 - https://doi.org/10.1063/1.1803914 VL - 85 IS - 15 SP - 3056 EP - 3058 PB - American Institute of Physics ER - TY - CHAP A1 - Höller, Christoph A1 - Blödt, Adrian A1 - Schneider, M. T1 - Kenngrößen elastisch gebundener Schüttungen auf Decken in Holzbauweisen T2 - Fortschritte der Akustik DAGA 2022: 48. Jahrestagung für Akustik, 21. - 24. März 2022, Stuttgart und Online Y1 - 2022 UR - https://www.dega-akustik.de/publikationen/online-proceedings PB - Deutsche Gesellschaft für Akustik e.V. CY - Berlin ER - TY - JOUR A1 - Chee, See Wee A1 - Kammler, Martin A1 - Balasubramanian, Prabhu A1 - Reuter, Mark C. A1 - Hull, Robert A1 - Ross, Frances M. T1 - Microstructural changes in silicon induced by patterning with focused ion beams of Ga, Si and Au JF - Ultramicroscopy N2 - We use focused beams of Ga(+), Au(+) and Si(++) ions to induce local microstructural changes in single crystal silicon. The ions were delivered as single spot pulses into thin Si membranes that could subsequently be imaged and annealed in situ in a transmission electron microscope. For each ion, the focused ion beam implantation created an array of amorphous regions in the crystalline membrane. Annealing causes solid phase epitaxial regrowth to take place, but we show that the resulting microstructure depends on the ion species. For Ga(+) and Au(+), precipitates remain after recrystallization, while for Si(++), dislocation loops form around the periphery of each implanted spot. We attribute these loops to defects formed during solid phase epitaxial regrowth, with controlled placement of the loops possible. KW - dislocation engineering KW - focused ion beam KW - In situ electron microscopy KW - solid phase epitaxial regrowth Y1 - 2013 U6 - https://doi.org/10.1016/j.ultramic.2012.07.004 VL - 127 SP - 126 EP - 131 PB - Elsevier ER - TY - CHAP A1 - Zheng, Jihong A1 - Fuhrmann, Thomas A1 - Xu, Boqing A1 - Schreiner, Rupert A1 - Jia, Hongzhi A1 - Zhang, Wei A1 - Wang, Ning A1 - Seebauer, Gudrun A1 - Zhu, Jiyan T1 - Curriculum design and German student exchange for Sino-German Bachelor program majored in optoelectronics engineering T2 - 14th Conference on Education and Training in Optics and Photonics (ETOP 2017), 29-31.05.2017, Hangzhou, China, 29-31.05.2017 N2 - Different higher education backgrounds in China and Germany led to challenges in the curriculum design at the beginning of our cooperative bachelor program in Optoelectronics Engineering. We see challenges in different subject requirements from both sides and in the German language requirements for Chinese students. The curriculum was optimized according to the AS IIN criteria, which makes it acceptable and und erstandable by both countries. German students are integrated into the Chinese class and get the sa me lectures like their Chinese colleagues. Intercultural and curriculum challenges are successfully solved. The results are summarized to provide an example for other similar international programs. KW - cooperative bachelor program KW - optoelectronics KW - microsystems KW - student exchange Y1 - 2017 U6 - https://doi.org/10.1117/12.2269574 PB - SPIE ER - TY - GEN ED - Babik, Wieslaw ED - Ohly, Heinz Peter ED - Weber, Karsten T1 - Theorie, Semantik und Organisation von Wissen T2 - Theory, Information and Organization of Knowledge KW - Informations- und Dokumentationswissenschaft KW - Wissensorganisation KW - Wissensextraktion KW - Automatische Sprachanalyse KW - Semantic Web KW - Indexierung KW - Scientific Community Y1 - 2017 SN - 978-3-95650-239-2 U6 - https://doi.org/10.5771/9783956503269 PB - Ergon Verlag CY - Würzburg ER - TY - JOUR A1 - Guertler, Katherine T1 - Mixed language learner levels in higher education as an adverse effect of post-secondary education de-tracking JF - Fremdsprachen und Hochschule : FuH N2 - Die unterschiedlichen Bildungswege in der deutschen Sekundarstufe führen abhängig von der Schulform zu abweichenden Lernergebnissen der Englischkompetenzen. Doch in der Tertiärstufe werden die Bildungswege wieder zusammengeführt und die Absolvent(inn)en aller Schulformen befinden sich in einer gemeinsamen Lernumgebung. Die vorgestellte empirische Untersuchung von über 450 Studierenden an zwei bayerischen Fachhochschulen hinsichtlich des Bildungshintergrunds und der Sprachkompetenzen belegt, dass die Lernenden in den nunmehr gemeinsamen Englischkursen im Tertiärbereich über stark unterschiedliche Kompetenzniveaus verfügen. Die Daten zeigen eine ausgeprägte Kaskade im Kompetenzniveau basierend auf der früheren Sekundarschulform, wobei Studierende der vertieften allgemeinbildenden Schule (Gymnasium) ihre Qualifikationen höher einschätzen als Studierende von berufsbildenden Sekundarschulen (FOS und BOS). Obwohl in allen bayerischen Sekundarschulformen mindestens das GER-Niveau B2 als Standard für Schulabgänger festgelegt ist, geben in der Stichprobe von Studierenden an Fachhochschulen mehr als die Hälfte der Lernenden das Niveau B1 in mindestens einer der Fertigkeiten für Englisch an; und etwas mehr als 8% der Studierenden berichten ihre Selbsteinschätzung in jeder Fertigkeit als Niveau B1 oder niedriger. Die Ergebnisse lassen erkennen, dass ein breites Spektrum an Kompetenzniveaus von B1 bis C1 an den Fachohochschulen häufig endemisch ist, und dass die derzeitige Praxis, Englischkurse im Tertiärbereich für die idealisierten B2-Lernenden zu gestalten, den Bedürfnissen vieler Studierenden nicht ausreichend entgegenkommt. KW - Bildungspolitik KW - Empirische Forschung KW - Englischunterricht KW - Fachhochschule KW - Fremdsprachenunterricht KW - Sekundarbereich KW - Tertiärbereich Y1 - 2018 SN - 0178-0336 VL - 92 SP - 19 EP - 36 PB - Clearingstelle d. AKS CY - Bochum ER - TY - BOOK A1 - Janssen, Johann A1 - Danz, Simone A1 - Eich-Stapf, Karin A1 - Sass, Elke A1 - Breutmann, Bern A1 - Hopfenmüller, Manfred A1 - Schmid, Andreas A1 - Wagner, Joachim T1 - Qualitätsmanagement für Hochschulen BT - Das Praxishandbuch N2 - Seit in den neunziger Jahren in Deutschland begonnen wurde das Konzept des Neuen Steuerungsmodels ("New Public Management") einzuführen, werden Hochschulen stärker als bisher an ihrer Leistungsfähigkeit gemessen. Um die öffentlichen Verwaltungen zu modernisieren, werden hierbei Managementtechniken aus der privaten Wirtschaft zur strategischen Steuerung an Hochschulen und an anderen öffentlichen Verwaltungen übernommen. Die Hochschulen werden verstärkt als Dienstleister wahrgenommen und stärker an ihrem tatsächlichen Output gemessen. Parallel dazu hat der internationale Wettbewerb zwischen Hochschulen zugenommen. Beide Entwicklungen erfordern von den Hochschulen, effektive Managementstrukturen zu entwickeln, die ihre Qualität und Leistungsfähigkeit sichern und systematisch weiterentwickeln. Hierbei dürfen aber die für den Erfolg der Hochschule essenziellen Faktoren wie Kreativität, Innovation und Diversität nicht eingeschränkt, sondern müssen vielmehr gestärkt werden. Zudem weisen Hochschulen mit ihren demokratischen hochschulpolitischen Gremien sowie der grundgesetzlich garantierten Freiheit von Forschung und Lehre besondere Strukturen auf, die sich grundsätzlich von denen privatwirtschaftlicher Unternehmen unterscheiden. Viele Aspekte klassischer Managementsysteme und die Prozesse zu deren Einführung können also nicht eins zu eins auf Hochschulen übertragen werden. In der DGQ-Arbeitsgruppe 360 "Einführung von Qualitätsmanagement an Hochschulen" haben Experten aus verschiedenen Hochschulen ihre Erfahrungen und ihr Wissen zusammengetragen, wie ein ganzheitliches Qualitätsmanagementsystem den besonderen Zielsetzungen und Strukturen von Hochschulen gerecht werden kann. In diesem Praxisbuch zeigen die Autoren Schritt für Schritt, wie ein solches Qualitätsmanagementsystem eingeführt und gestaltet werden kann und wie es die Qualität und Leistungsfähigkeit der Hochschule erhöhen kann. Dabei wird ein starker Fokus auf die Prozessorientierung und den Einsatz von Verbesserungszyklen gelegt. Die relevanten Standards und Normen werden beschrieben und die wichtigsten Begriffe geklärt. Besonders wertvoll sind aber sicher die vielen Beispiele aus über 20 Hochschulen und die Erläuterungen zu typischen Stolpersteinen und wichtigen Erfolgsfaktoren - zum Beispiel die große Bedeutung von Kommunikation und Projektmanagement bei der Einführung eines Qualitätsmanagementsystems. Mit diesem Buch hat die Arbeitsgruppe eine Hilfestellung für Praktiker erarbeitet, die sich in Präsidien, Verwaltungsreferaten und den Fachbereichen der Hochschulen mit dem integrierten Management, der Evaluation von Forschung, Studium und Lehre oder der Qualitätssicherung beschäftigen. Zudem leistet sie einen wertvollen Beitrag, den Qualitätsgedanken auf die spezielle Organisation Hochschule zu übertragen. KW - Ausbildungsunterlage KW - Deutschland KW - Dienstleister KW - Erfolgsfaktor KW - Handbuch KW - Innovation KW - Kreativität KW - Managementsystem KW - Projektmanagement KW - Prozessorientierung KW - Qualitätsmanagement KW - Qualitätssicherung KW - Universität KW - Wettbewerb Y1 - 2015 U6 - https://doi.org/10.3139/9783446443976.fm PB - Hanser CY - München ER - TY - CHAP A1 - Blahníková, Barbora A1 - Müller, D. A1 - Waas, M. A1 - Lechner, Alfred T1 - Multilyzer - Mikrofluidisches Echtzeitmesssystem für die Analyse umweltrelevanter Substanzen T2 - 7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, München N2 - Die übermäßige Verwendung von stickstoffbasierten Düngemitteln in der Landwirtschaft stellt eine Gefährdung für die Umwelt und Lebewesen dar. So ist die Analyse von Boden- und Grundwasser zu einem wesentlichen Bestandteil der Nachhaltigkeit und der ökologischen Erhaltung geworden. Dafür bietet der Multilyzer eine passende Lösung. Der Multilyzer ist ein mikrofluidisches Analysesystem zur Bestimmung niedrigster Konzentrationen von Nitrat, Nitrit und Ammonium, die alle wesentliche Bestandteile des Stickstoffkreislaufs sind. Welche bei Übermäßiger Aufnahme im Körper krebserregend wirken und den Sauerstofftransport im Blutkreislauf stören. Der Aufbau ist eine Kombination aus Absorptions- und Fluoreszenzspektroskopie. Der Betrieb mit einer 12 Volt Batterie ermöglicht die Verwendung des Multilyzer-Systems zur Online-Messung im Feld. Somit können sehr kurze Analysezeiten realisiert und der Einfluss von Umwandlungs- bzw. Abbauprozessen vermieden werden. Das gesamte Messsystem wird im Kompetenzzentrum Nanochem an der OTH Regensburg entwickelt, inklusive Fertigungstechnologien, Software- und Hardwaresteuerung. N2 - Excessive use of nitrogen based fertilizers in agriculture represents an environmental hazard. Thus, analysis of soil water and groundwater has become an essential part of sustainability and ecological preservation. On this account, the Multilyzer provides a suitable solution. The Multilyzer is a microfluidic measuring system for the determination of lowest concentrations of nitrate, nitrite and ammonium, which are essential components of the nitrogen cycle. The measurement combines the principles of absorption and fluorescence spectroscopy. As a transportable unit, online measurements can be carried out using a 12 Volts battery power supply. Consequently, the influence of conversion and degradation processes can be avoided. The complete device is developed at the Centre of Excellence Nanochem at OTH Regensburg including fabrication technologies, software and hardware control. T2 - Multilyzer - Microfluidic Online Measuring System for the Analysis of Environmentally Relevant Substances KW - Absorptionsspektroskopie KW - Ammonium KW - Analysensystem KW - Blutkreislauf KW - Bodenwasser KW - Düngemittel KW - Echtzeitsystem KW - Fluoreszenzspektroskopie KW - Messgerät KW - Messsystem KW - Mikrofluidik KW - Nachhaltigkeit KW - Nitrat KW - Nitrit KW - Online-Messung KW - Programmsteuerung KW - Stickstoff Y1 - 2017 SN - 978-3-8007-4491-6 SP - 382 EP - 385 PB - VDE-Verlag CY - München ER - TY - CHAP A1 - Bieker, Johannes A1 - Roustaie, Farough A1 - Langer, Christoph A1 - Schreiner, Rupert A1 - Schlaak, Helmut F. T1 - Innovatives Verfahren zur Herstellung und Integration metallischer Nanokonen für die Feldemission T2 - MikroSystemTechnik Kongress 2017 : MEMS, Mikroelektronik, Systeme 23.-25. Oktober 2017 in München N2 - In den letzten Jahren wurde am Institut für Elektromechanische Konstruktionen die Fabrikation und Integration von metallischen Nanodrähten und Nanokonen mittels Template-basierter Abscheidung erforscht. Diese Variante der in-situ Abscheidung von metallischen Nanostrukturen bietet eine Vielzahl von Anwendungsmöglichkeiten. Im Rahmen dieses Beitrags werden das Herstellungsverfahren zur Herstellung metallischer Nanokonen vorgestellt. Dies beinhaltet sowohl die Templatepräparation mittels asymmetrischen Ätzens als auch die anschließende Integration mittels galvanischer Abscheidung. Eine Anwendung der metallischen Nanokonen stellt die Verwendung als Feldemitter in der Vakuumelektronik dar. Es werden erste Messungen der Langzeitstabilität des Feldemissionsstromes der metallischen Konen präsentiert. N2 - Recently the fabrication and integration of metallic nanowires and nanocones based on ion-track etched templates has been in the focus of research at the Institute for Electromechanical Design at the TU Darmstadt. Using the method for the in-situ deposition various applications are feasible. In this paper we present the fabrication method for in-situ deposition of metallic nanocones, including the preparation of the polymer templates based on asymmetric etching and the process description for integration via electrodeposition. Giving one example for an application, the metallic nanocones can be used as field emitters in vacuum electronics. The field emission properties will be presented briefly. T2 - Innovative fabrication method for in-situ deposition of metallic nanocones for field emission KW - Ätzen KW - Feldemission KW - galvanische Abscheidung KW - Herstellverfahren KW - Langzeitstabilität KW - Nanodraht KW - Nanostruktur KW - Polymer KW - Prozessbeschreibung KW - Vakuum Y1 - 2017 SN - 978-3-8007-4491-6 IS - CD-ROM SP - 797 EP - 800 PB - VDE-Verlag CY - München ER - TY - CHAP A1 - Betz, Michael A. A1 - Lechner, Alfred T1 - Sprayganik - Spraytool für organische Halbleiter T2 - 7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, München N2 - Sprühbeschichtung stellt einen kostengünstigen und materialeffizienten aber komplexen Prozess dar. Um diese Vorteile für die Abscheidung teurer organischer Halbleiter zu nutzen, wurde ein Sprühbeschichter entwickelt, der neueste Anforderungen an den Prozess erfüllt. Zudem konnten selbstansaugende Mikrosprühdüsen mikrotechnologisch in Silizium realisiert werden, welche bereits eine bis zu vierfache Materialeffizienz im Vergleich zu herkömmlichen airbrush-Düsen nachweisen konnten. Die neueste Düsengeneration zeigt nun eine weiter verbesserte Zerstäubung, was bei gesprühten OPDs zu einer reduzierten Dunkelstromdichte von 9,1×10-6 mA·cm-2 (-5 V) und erhöhten externen Quanteneffizienz von 78,5% (530 nm, -5 V) führt. N2 - Generally, spray coating is a cheap and material efficient but complex process. To exploit those advantages for deposition of expensive organic semiconductors, we developed a spray coater to fulfil latest requirements. Furthermore, it was possible to realize venturi micro nozzles that already showed up to 4-fold material efficiency when compared to conventional airbrush-nozzles. The latest nozzle layout shows an even better atomization resulting in photodiodes with a reduced dark current density of 9,1×10-6 mA·cm-2 (-5 V) and increased external quantum efficiency of 78,5% (530 nm, -5 V). KW - Dunkelstrom KW - organischer Halbleiter KW - Photodiode KW - Silicium KW - Spritzbeschichten KW - Spritzschicht KW - Sprühdüse KW - Zerstäubung Y1 - 2017 SN - 978-3-8007-4491-6 SP - 747 EP - 750 PB - VDE-Verlag CY - München ER - TY - INPR A1 - Amat, A. A1 - Halimah, M. K. A1 - Ishak, M. A1 - Nazrin, S. N. A1 - Syamimi, Nik Nur A1 - Hasnimulyati, L. T1 - Electronic Polarizability and Optical Basicity of BaO-B2O3-TeO2 Glass System N2 - [(TeO2)0.7(B2O3)0.3]1-x (BaO)x, x = 0.00, 0.05, 0.10, 0.20, 0.25, 0.30 and 0.35 mol fraction glass series were successfully synthesized by conventional melt quenching method. Amorphous phase of all samples was confirmed through X-ray diffraction while optical properties were determined using UV-VIS spectrophotometer. Fourier Transform Infrared (FTIR) analysis showed that the glass structure consisted of TeO3, TeO4, TeO6, BO3 and BO4 structural units. The optical band gap energy, Eopt which was calculated from Tauc’ plots decreased as the amount of BaO increases, whereas, the Urbach energy value increased. The increase in Urbach energy value was attributed to the increase of defects in glass structure. The refractive indices of glass were found to increase along with the increased amount of BaO, due to the high polarization and high density of host material and glass modifier. The molar polarizability, αm, oxide ion polarizability, αo2- and optical basicity, Λ of the glasses are calculated by Lorentz-Lorenz equation. The glasses were found to possess αm values between 8.106 – 8.489 Å3, and αo2- values between 3.303 to 4.772. Meanwhile, optical basicity increases from 0.115 to 0.893.

Y1 - 2021 U6 - https://doi.org/10.21203/rs.3.rs-1093838/v1 ET - Version 1, posted 30 Nov, 2021 ER - TY - CHAP A1 - Rahiman, Mohd Fuad A1 - Berndt, Dominik A1 - Schreiner, Rupert T1 - Micro-wire Pirani with temperature-stabilized Environment T2 - 3. Symposium Elektronik und Systemintegration ESI 2022: 06. April 2022, Hochschule Landshut Y1 - 2022 SN - 978-3-9818439-7-2 SP - 52 EP - 59 ER - TY - GEN A1 - Schreiner, Rupert T1 - Miniaturized sensor and actuator elements based on the heat transport in gases or the ionization of gas particles T2 - 16th International Conference on Optical and Electronic Sensors, COE'2020, 29 March - 2 April 2020, Krakow, Poland (online) Y1 - 2021 ER - TY - BOOK ED - Weber, Karsten ED - Friesen, Hans ED - Zoglauer, Thomas T1 - Philosophie und Phantastik KW - Das Fantastische KW - Fantasie KW - Film KW - Literatur KW - Philosophie KW - Spiel Y1 - 2016 SN - 978-3-95743-073-1 PB - Mentis CY - Münster ER - TY - CHAP A1 - Kleshch, Victor I. A1 - Serbun, Pavel A1 - Orekhov, Anton A1 - Lützenkirchen-Hecht, Dirk A1 - Obraztsov, Alexander N. A1 - Prommesberger, Christian A1 - Langer, Christoph A1 - Schreiner, Rupert A1 - Lutzenkirchen-Hecht, Dirk T1 - Field emission properties of p-type silicon tips decorated with tungsten nanoparticles T2 - 2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany N2 - An array of conical-shaped p-type silicon tips was fabricated by using reactive ion etching and sharpening oxidation. The apex of each tip was decorated by a tungsten hemispherical nanoparticle. Field emission properties of the tips were measured by a tungsten-needle anode positioned above the tip apex. Tips decorated with tungsten nanoparticles demonstrated a smaller saturation region in current-voltage characteristics compared to the pristine tips. An emission activation process, which consisted in sudden current increase at certain value of applied voltage, was observed for the decorated silicon tips. This behavior was explained by the formation of vertical protrusions extending from the metal particles revealed by scanning electron microscopy after field emission experiments. KW - Current measurement KW - field emission KW - Ions KW - Iron KW - metal nanoparticles KW - nanoparticles KW - p-type silicon KW - Scanning electron microscopy KW - silicon KW - Tungsten Y1 - 2017 U6 - https://doi.org/10.1109/IVNC.2017.8051580 SP - 138 EP - 139 PB - IEEE ER - TY - CHAP A1 - Wick, Michael A1 - Lindner, Gerhard A1 - Zimmer, Katja A1 - Schreiner, Rupert A1 - Fuhrmann, Thomas A1 - Seebauer, Gudrun A1 - Xu, Boqing A1 - Zheng, Jihong A1 - Wang, Ning ED - Liu, Xu ED - Zhang, Xi-Cheng T1 - German-Chinese cooperative Bachelor in engineering physics/optoelectronics T2 - 14th Conference on Education and Training in Optics and Photonics: ETOP 2017; Hangzhou, China 29.05.2017 - 31.05.2017 N2 - The University of Shanghai for Science and Technology (USST), the Coburg University of Applied Sciences and Arts (CUASA) and the OTH Regensburg, University of Applied Sciences (OTHR) established an English taught international cooperative bachelor program in the area of Engineering Physics/Optoelectronics. Students from China study their first four semesters at USST. They continue their studies in Germany for the last three semesters, including an internship and a bachelor thesis, graduating with a Chinese and a German bachelor degree. Students from Germany study their third and fourth semester at USST to gain international experience. While the first cohort of Chinese students is currently in Germany, the second cohort of German students is in Shanghai. Up to now the feedback regarding this study program is completely positive, thus it is planned to develop it further. Y1 - 2017 SN - 9781510613812 U6 - https://doi.org/10.1117/12.2269943 PB - SPIE ER - TY - CHAP A1 - Knapp, Wolfram A1 - Langer, Christoph A1 - Prommesberger, Christian A1 - Lindner, Matthias A1 - Schreiner, Rupert T1 - Investigations of the transition from field electron emission to stable plasma discharge in a micro electron source at vacuum pressure T2 - 2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany N2 - We report on the transition from field electron emission to plasma discharges. During an experiment with a miniaturized field emission electron source a plasma discharge accompanied by a luminous effect was observed. A novel graphical evaluation method was used to interpret and to compare the observed phenomenon. KW - CATHODES KW - Discharges (electric) KW - electron source KW - electron sources KW - Fault location KW - field emission KW - field emission measurement KW - glow discharge KW - Glow discharges KW - micro arc KW - plasma discharge KW - Plasmas KW - Si-tip cathode Y1 - 2017 U6 - https://doi.org/10.1109/IVNC.2017.8051594 SP - 166 EP - 167 PB - IEEE ER - TY - GEN A1 - Hartmann, Julia A1 - Sattler, Florian T1 - Knowledge Nuggets in der Lehre KW - Knowledge Nuggets KW - Innovation in der Lehre Y1 - 2024 ER - TY - JOUR A1 - Wunderlich, Lukas A1 - Hausler, Peter A1 - Maerkl, Susanne A1 - Bierl, Rudolf A1 - Hirsch, Thomas T1 - Nanoparticle Determination in Water by LED-Excited Surface Plasmon Resonance Imaging JF - Chemosensors N2 - The increasing popularity of nanoparticles in many applications has led to the fact that these persistent materials pollute our environment and threaten our health. An online sensor system for monitoring the presence of nanoparticles in fresh water would be highly desired. We propose a label-free sensor based on SPR imaging. The sensitivity was enhanced by a factor of about 100 by improving the detector by using a high-resolution camera. This revealed that the light source also needed to be improved by using LED excitation instead of a laser light source. As a receptor, different self-assembled monolayers have been screened. It can be seen that the nanoparticle receptor interaction is of a complex nature. The best system when taking sensitivity as well as reversibility into account is given by a dodecanethiol monolayer on the gold sensor surface. Lanthanide-doped nanoparticles, 29 nm in diameter and with a similar refractive index to the most common silica nanoparticles were detected in water down to 1.5 mu g mL(-1). The sensor can be fully regenerated within one hour without the need for any washing buffer. This sensing concept is expected to be easily adapted for the detection of nanoparticles of different size, shape, and composition, and upon miniaturization, suitable for long-term applications to monitor the quality of water. KW - ENGINEERED NANOPARTICLES KW - imaging KW - nanoparticle KW - plasmon resonance KW - REFRACTIVE-INDEX KW - sensor KW - surface Y1 - 2021 U6 - https://doi.org/10.3390/chemosensors9070175 SN - 2227-9040 VL - 9 IS - 7 SP - 1 EP - 9 PB - MDPI ER - TY - JOUR A1 - Schreiner, Rupert A1 - Schweizer, Heinz C. T1 - High-frequency operation of 1.57-μm laterally coupled distributed feedback lasers with self-aligned ohmic contacts and nickel surface gratings JF - IEEE Journal of Selected Topics in Quantum Electronics N2 - Laterally coupled distributed feedback lasers with self-aligned ohmic contacts show the advantage of a considerably simplified fabrication process. These lasers exhibit superior spectral properties with full benefit from the gain coupling mechanism. Side-mode suppression ratios up to 55- and 3-dB bandwidths beyond 15 GHz were obtained for these devices. KW - Distributed feedback devices KW - Optical coupling KW - Laser feedback KW - Ohmic contacts KW - Nickel KW - Surface emitting lasers KW - Gratings KW - Optical device fabrication KW - Mechanical factors KW - Bandwidth Y1 - 2003 U6 - https://doi.org/10.1109/JSTQE.2003.819469 VL - 9 IS - 5 SP - 1179 EP - 1182 PB - IEEE ER - TY - JOUR A1 - Bender, Guzide A1 - Fahrioglu Yamaci, Rezan A1 - Taneri, Bahar T1 - CRISPR and KRAS: a match yet to be made JF - Journal of biomedical science N2 - CRISPR (clustered regularly interspaced short palindromic repeats) systems are one of the most fascinating tools of the current era in molecular biotechnology. With the ease that they provide in genome editing, CRISPR systems generate broad opportunities for targeting mutations. Specifically in recent years, disease-causing mutations targeted by the CRISPR systems have been of main research interest; particularly for those diseases where there is no current cure, including cancer. KRAS mutations remain untargetable in cancer. Mutations in this oncogene are main drivers in common cancers, including lung, colorectal and pancreatic cancers, which are severe causes of public health burden and mortality worldwide, with no cure at hand. CRISPR systems provide an opportunity for targeting cancer causing mutations. In this review, we highlight the work published on CRISPR applications targeting KRAS mutations directly, as well as CRISPR applications targeting mutations in KRAS-related molecules. In specific, we focus on lung, colorectal and pancreatic cancers. To date, the limited literature on CRISPR applications targeting KRAS, reflect promising results. Namely, direct targeting of mutant KRAS variants using various CRISPR systems resulted in significant decrease in cell viability and proliferation in vitro, as well as tumor growth inhibition in vivo. In addition, the effect of mutant KRAS knockdown, via CRISPR, has been observed to exert regulatory effects on the downstream molecules including PI3K, ERK, Akt, Stat3, and c-myc. Molecules in the KRAS pathway have been subjected to CRISPR applications more often than KRAS itself. The aim of using CRISPR systems in these studies was mainly to analyze the therapeutic potential of possible downstream and upstream effectors of KRAS, as well as to discover further potential molecules. Although there have been molecules identified to have such potential in treatment of KRAS-driven cancers, a substantial amount of effort is still needed to establish treatment strategies based on these discoveries. We conclude that, at this point in time, despite being such a powerful directed genome editing tool, CRISPR remains to be underutilized for targeting KRAS mutations in cancer. Efforts channelled in this direction, might pave the way in solving the long-standing challenge of targeting the KRAS mutations in cancers. KW - Animals KW - Clustered Regularly Interspaced Short Palindromic Repeats KW - Humans KW - Mice KW - Mutation KW - Proto-Oncogene Proteins p21(ras)/therapeutic use Y1 - 2021 U6 - https://doi.org/10.1186/s12929-021-00772-0 VL - 28 SP - 1 EP - 25 PB - Springer Nature ER - TY - CHAP A1 - Hausler, Peter A1 - Roth, Carina A1 - Vitzthumecker, Thomas A1 - Bierl, Rudolf ED - Ribeiro, Paulo ED - Raposo, Maria T1 - Miniaturized Surface Plasmon Resonance Based Sensor Systems BT - Opportunities and Challenges T2 - Optics, Photonics and Laser Technology 2018 N2 - Surface Plasmon Resonance (SPR) is a well-known and established technology in bioanalysis and pharmaceutical sciences. Due to the expensive instrumentation and the need of trained people, it is mainly limited to applications in laboratories. However, there are some areas like environmental monitoring, chemical processing and civil infrastructure, which urgently need new sensor technologies. SPR has the potential to serve these fields. In order to be qualified for a use in these areas SPR has to overcome some hurdles. The instrumentation has to be robust, small in size and cheap. A device, which fits these needs, will be a micro-opto-electro-mechanical system (MOEMS) with integrated intelligent algorithms. In this book chapter, examples of miniaturized SPR devices are introduced, the limitations which have to be overcome as well as the possibilities for future applications are proposed. Due to the manifold advantages of this technology and the dropping prices for imaging sensors, Surface Plasmon Resonance imaging (SPRi) might become one of the leading technologies for SPR smart sensor systems. Y1 - 2019 SN - 978-3-030-30112-5 U6 - https://doi.org/10.1007/978-3-030-30113-2_8 SP - 169 EP - 195 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Singla, Rashmi A1 - de Ponte, Ulrike ED - Mayer, Claude-Hélène ED - Vanderheiden, Elisabeth T1 - Love in the Context of Transnational Academic Exchanges: Promoting Mental Health and Wellbeing T2 - International Handbook of Love N2 - Educational and cultural dimensions of transnational academic exchange such as student exchanges, double degree programmes, internships have been researched but the romantic dimensions are almost overlooked, especially qualitatively, while Green (EU’s Erasmus study abroad programme is ‘responsible for 1m babies’, 2014) documents that one quarter students on Erasmus exchange scheme met their long-term partner while studying abroad. The chapter explores love, with focus on formation of intimate relations in academic exchanges in the European settings. The method is case-studies drawn from two projects based in Denmark, the first about ethnically intermarried couples (Singla, Intermarriage and mixed parenting: Promoting mental health & wellbeing, crossover love. Palgrave Macmillan, 2015) and the second, an ongoing project about LAT (Living Apart Together) transnational couples (Singla & Varma, LAT (Living Apart Together) transnational couples: Promoting mental health and wellbeing, 2018), moving beyond ‘methodological nationalism and- conjugalism’. The theoretical framework is Cultural Psychology and foreground is a combination of Narrative Psychology, intersectionality, digital emotional reflexivity and transnationalism. Moreover, aspects related to figuring out criteria of the exchange situation abroad, which can underpin explaining the high rate of long-term relationships while studying abroad, are included. Those aspects are based on a framework, in which intercultural and developmental psychological findings are linked. The 3–4 case studies are drawn from empirical research with eight couples in the first study and 20 couples in the second. The narratives are thematically analysed, whereas two themes regarding participants’ motivation for establishing relationship despite differences and long-term sustaining of the relationship are described in the chapter. Preliminary findings nuance the phenomenon of love in academic exchanges, invoking concepts such as educational homogamy, balancing independence and togetherness, diversities of connectivities intersecting social media and intimacies. Furthermore, the significant others’ support and opposition of these couples’ love dynamics are covered, along with considerations linked to the concept of the emotional availability (Saunders, Kraus, Barone & Biringen, Frontiers in Psychology, 2015) based on Bowlby’s attachment theory and the shared third (Benjamin, Psychoanalytic Quarterly, 73(1), 5–46, 2004). Lastly, ‘good practices’ for promoting the mental health and wellbeing of such academic exchange couples are delineated along with suggestions for relevant services for those experiencing psychosocial problems. Educational and cultural dimensions of transnational academic exchange such as student exchanges, double degree programmes, internships have been researched but the romantic dimensions are almost overlooked, especially qualitatively, while Green (EU’s Erasmus study abroad programme is ‘responsible for 1m babies’, 2014) documents that one quarter students on Erasmus exchange scheme met their long-term partner while studying abroad. The chapter explores love, with focus on formation of intimate relations in academic exchanges in the European settings. The method is case-studies drawn from two projects based in Denmark, the first about ethnically intermarried couples (Singla, Intermarriage and mixed parenting: Promoting mental health & wellbeing, crossover love. Palgrave Macmillan, 2015) and the second, an ongoing project about LAT (Living Apart Together) transnational couples (Singla & Varma, LAT (Living Apart Together) transnational couples: Promoting mental health and wellbeing, 2018), moving beyond ‘methodological nationalism and- conjugalism’. The theoretical framework is Cultural Psychology and foreground is a combination of Narrative Psychology, intersectionality, digital emotional reflexivity and transnationalism. Moreover, aspects related to figuring out criteria of the exchange situation abroad, which can underpin explaining the high rate of long-term relationships while studying abroad, are included. Those aspects are based on a framework, in which intercultural and developmental psychological findings are linked. KW - Academic exchange KW - Diversities of connectivities KW - Educational homogamy KW - Emotional availability KW - Intimate relationship KW - Love KW - Narrative psychology Y1 - 2021 SN - 978-3-030-45995-6 U6 - https://doi.org/10.1007/978-3-030-45996-3_32 VL - 67 SP - 599 EP - 620 PB - Springer International Publishing CY - Cham ER - TY - JOUR A1 - Bedi-Visschers, Marion T1 - Von der hilfreichen Kätzin zum Gestiefelten Kater JF - Tierstudien 15/2019 : Tiere erzählen Y1 - 2019 UR - https://download.e-bookshelf.de/download/0012/6113/68/L-O-0012611368-0041192977.pdf VL - 8 IS - 15 SP - 33 EP - 44 PB - Neofelis Verlag ER - TY - JOUR A1 - Rothleitner, Christian A1 - Schlamminger, Stephan T1 - Invited Review Article: Measurements of the Newtonian constant of gravitation, G JF - Review of Scientific Instruments N2 - By many accounts, the Newtonian constant of gravitation G is the fundamental constant that is most difficult to measure accurately. Over the past three decades, more than a dozen precision measurements of this constant have been performed. However, the scatter of the data points is much larger than the uncertainties assigned to each individual measurement, yielding a Birge ratio of about five. Today, G is known with a relative standard uncertainty of 4.7 x 10(-5), which is several orders of magnitudes greater than the relative uncertainties of other fundamental constants. In this article, various methods to measure G are discussed. Alarge array of different instruments ranging from the simple torsion balance to the sophisticated atom interferometer can be used to determine G. Some instruments, such as the torsion balance can be used in several different ways. In this article, the advantages and disadvantages of different instruments as well as different methods are discussed. A narrative arc from the historical beginnings of the different methods to their modern implementation is given. Finally, the article ends with a brief overview of the current state of the art and an outlook. KW - acceleration KW - ADJUSTMENT KW - ATOM KW - BALANCE KW - CODATA RECOMMENDED VALUES KW - FORCE KW - FUNDAMENTAL PHYSICAL CONSTANTS KW - INTERFEROMETRY KW - MASS KW - PRECISION-MEASUREMENT Y1 - 2017 U6 - https://doi.org/10.1063/1.4994619 VL - 88 IS - 11 PB - AIP Publishing ER - TY - JOUR A1 - Dams, Florian A1 - Schreiner, Rupert T1 - Influencing factors on the sensitivity of MEMS-based thermal conductivity vacuum gauges JF - Journal of vacuum science & technology A N2 - The measurement range of thermal conductivity vacuum gauges is mainly influenced by the sensitivity of the sensing element to variations in pressure. An enhanced definition of sensitivity shows its theoretical dependence on the geometric measures of the sensor element at the whole pressure range. This value gives the possibility of direct comparison between different types of sensor structures without the influence of the operating conditions. To study the influencing factors, sensor chips with heated surfaces in the order of some tens of mm 2 were realized by microelectromechanical systems-based fabrication techniques. By a silicon-glass hybrid process two cold planes were formed in a distance of 150 mu m above and below the heated element. The thermal conductance of devices with different geometric measures was determined in constant temperature operating mode by usage of embedded measurement equipment. In this configuration the sensor signals were sensitive to pressure in a region from 10(-5) mbar. The sensitivity was extracted by a fit of the theoretical model to the measurement data and showed the predicted dependencies on the geometric measures. (C) 2014 American Vacuum Society. KW - Pirani Gauge KW - Pressure Sensor Y1 - 2014 U6 - https://doi.org/10.1116/1.4867486 VL - 32 IS - 3 PB - AVS ER - TY - JOUR A1 - Betz, Michael A. A1 - Büchele, Patric A1 - Brünnler, Manfred A1 - Deml, Sonja A1 - Lechner, Alfred T1 - Silicon micro venturi nozzles for cost-efficient spray coating of thin organic P3HT/PCBM layers JF - Journal of micromechanics and microengineering N2 - Improvements on spray coating are of particular interest to different fields of technology as it is a scalable deposition method and processing from solutions offer various application possibilities outside of typical facilities. When it comes to the deposition of expensive and film-forming media such as organic semiconductors, consumption and nozzle cleaning issues are of particular importance. We demonstrate the simple steps to design and fabricate micro venturi nozzles for economical spray coating with a consumption as low as 30-50 mu l.min(-1). For spray coating an active area of 25 cm(2) a 2.45-4.01 fold coating efficiency is observed compared to a conventional airbrush nozzle set. The electrical characterization of first diodes sprayed with an active layer thickness of similar to 750 nm using a single micronozzle at a coating speed of 1.7 cm(2).min(-1) reveals a good external quantum efficiency of 72.9% at 532 nm and a dark current of similar to 7.4.10(-5) mA.cm(-2), both measured at -2 V. Furthermore, the high resistance of the micronozzles against solvents and most acids is provided through realization in a silicon wafer with silicon dioxide encapsulation, therefore allowing easy and effective cleaning. KW - deep reactive ion etching KW - microfluidics KW - organic photodiodes KW - organic semiconductors KW - spray coating KW - venturi nozzles Y1 - 2017 U6 - https://doi.org/10.1088/0960-1317/27/1/015019 VL - 27 IS - 1 PB - IOP Publishing ER - TY - JOUR A1 - Liebherr, Raphaela B. A1 - Hutterer, Albert A1 - Mickert, Matthias J. A1 - Vogl, Franziska C. A1 - Beutner, Andrea A1 - Lechner, Alfred A1 - Hummel, Helmut A1 - Gorris, Hans H. T1 - Three-in-one enzyme assay based on single molecule detection in femtoliter arrays JF - Analytical and bioanalytical chemistry N2 - Large arrays of femtoliter-sized chambers are important tools for single molecule research as well as bioanalytical applications. We have optimized the design and fabrication of two array types consisting of 250 × 250 (62 500) femtoliter chambers either by surface etching of fused silica slides or by polydimethylsiloxane (PDMS) molding. Highly diluted solutions of β-galactosidase were enclosed in such arrays to monitor the fluorogenic reactions of hundreds of individual enzyme molecules in parallel by wide-field fluorescence microscopy. An efficient mechanical sealing procedure was developed to prevent diffusion of the fluorescent reaction product out of the chambers. Different approaches for minimizing non-specific surface adsorption were explored. The signal acquisition was optimized to grant both a large field of view and an efficient signal acquisition from each femtoliter chamber. The optimized femtoliter array has enabled a three-in-one enzyme assay system: First, the concentration of active enzyme can be determined in a digital way by counting fluorescent chambers in the array. Second, the activity of the enzyme bulk solution is given by averaging many individual substrate turnover rates without the need for knowing the exact enzyme concentration. Third-unlike conventional enzyme assays-the distribution of individual substrate turnover rates yields insight into the conformational heterogeneity in an enzyme population. The substrate turnover rates of single β-galactosidase molecules were found to be broadly distributed and independent of the type of femtoliter array. In general, both types of femtoliter arrays are highly sensitive platforms for enzyme analysis at the single molecule level and yield consistent results. KW - ARRAYS KW - Digital concentration readout KW - Enzyme kinetics KW - Fluorescence microscopy KW - Single molecule detection Y1 - 2015 U6 - https://doi.org/10.1007/s00216-015-8910-0 VL - 407 IS - 24 SP - 7443 EP - 7452 PB - Springer ER - TY - JOUR A1 - Ruhl, Guenther A1 - Wittmann, Sebastian A1 - Koenig, Matthias A1 - Neumaier, Daniel T1 - The integration of graphene into microelectronic devices JF - Beilstein Journal of Nanotechnology N2 - Since 2004 the field of graphene research has attracted increasing interest worldwide. Especially the integration of graphene into microelectronic devices has the potential for numerous applications. Therefore, we summarize the current knowledge on this aspect. Surveys show that considerable progress was made in the field of graphene synthesis. However, the central issue consists of the availability of techniques suitable for production for the deposition of graphene on dielectric substrates. Besides, the encapsulation of graphene for further processing while maintaining its properties poses a challenge. Regarding the graphene/metal contact intensive research was done and recently substantial advancements were made towards contact resistances applicable for electronic devices. Generally speaking the crucial issues for graphene integration are identified today and the corresponding research tasks can be clearly defined. KW - BORON-NITRIDE KW - CHEMICAL-VAPOR-DEPOSITION KW - CONTACT-RESISTANCE KW - contacts KW - COPPER FOILS KW - deposition KW - ELECTRODES KW - encapsulation KW - FILMS KW - graphene KW - GROWTH KW - LOW-TEMPERATURE KW - process integration KW - RAMAN-SPECTROSCOPY KW - SUBSTRATE Y1 - 2017 U6 - https://doi.org/10.3762/bjnano.8.107 VL - 8 SP - 1056 EP - 1064 PB - Beilstein-Institut ER - TY - CHAP A1 - Zeitler, Berndt A1 - Hoeller, Christoph A1 - Reinhold, Steffi T1 - Maximum Fast time-weighted levels - When can a transient be seen as a Dirac impulse? T2 - Internoise 2023, 20–23 August 2023, Chiba, Greater Tokyo N2 - It is common practice to use maximum FAST time-weighted sound pressure levels to assess transient impact noise, as these levels correlate well with human perception of impact noise. Maximum FAST time-weighted levels are known to be dependent on the reverberation time of the receiving room. In previous studies, an analytical correction term was developed using a Dirac impulse. The correction term is used to calculate the maximum FAST time-weighted levels from peak sound pressure levels. Peak levels are independent of the reverberation time of the room. Applying the correction term makes it possible to compare measurement results from different rooms. The correction term has been validated in several studies for the standard rubber impact ball. In this paper, the influence of the source signal (Dirac impulse) on the correction term is studied. Analytical and numerical models are employed to investigate the consequences of stretching the impulse in time and of changing its shape. The results are compared with empirical solutions developed in other studies. Y1 - 2023 UR - https://www.researchgate.net/publication/373546707_Maximum_Fast_time-weighted_levels_-_When_can_a_transient_be_seen_as_a_Dirac_impulse ER - TY - CHAP A1 - Blödt, Adrian A1 - Höller, Christoph T1 - Akustische Verbesserungsmaßnahmen an Stoßstellen im Holzbau T2 - Fortschritte der Akustik DAGA 2022: 48. Jahrestagung für Akustik, 21. - 24. März 2022, Stuttgart und Online Y1 - 2022 PB - Deutsche Gesellschaft für Akustik e.V. CY - Berlin ER - TY - RPRT A1 - Höller, Christoph A1 - Zeitler, Berndt A1 - Sabourin, Ivan T1 - Airborne and impact sound insulation data for cold-formed steel-framed walls and floors N2 - This report presents the results of an extensive series of direct sound insulation tests of cold-formed steel-framed walls and floors. The direct airborne sound insulation of 30 walls with cold-formed steel framing was measured in accordance with ASTM E90-09. The walls had steel studs with a depth of 92 mm (3-5/8”) or 152 mm (6”), and with a steel thickness of 1.09 mm (0.043”) or 1.37 mm (0.054”). Other parameters that were investigated included the number of layers and thickness of gypsum board, the cavity insulation, the stud spacing, and the use of resilient channels. The test results for some non-standard wall configurations that were tested for research purposes (e.g. for walls with gypsum board on one side only) are also included in this report. The direct airborne and impact sound insulation of 17 floors with cold-formed steel framing was measured in accordance with ASTM E90-09 and ASTM E492-09, respectively. The floors had steel joists with a depth of 254 mm (10”) or 317 mm (12.5”), and with a steel thickness of 1.37 mm (0.054”). The top surface of the floor/ceiling assemblies was composed of a corrugated steel deck with poured gypsum concrete, while the bottom surface was composed of a gypsum board ceiling on resilient channels. The influence of the joist depth and the number of layers and thickness of the ceiling gypsum board was investigated, as well as the influence of several floor coverings (e.g. laminate or carpet). The report presents the detailed specimen descriptions and specimen properties and the results from the standardized tests according to ASTM E90-09 and ASTM E492-09. Brief analyses of the parameters affecting the sound insulation of the steel-framed assemblies are provided. The tests presented in this report were part of a large research study that also included an investigation into the flanking sound transmission in cold-formed steel-framed buildings. The results of that study are described in the NRC Research Report RR-337, “Apparent Sound Insulation in Cold-Formed Steel-Framed Buildings” [1]. The NRC Research Report RR-337 also includes some of the airborne sound insulation results presented here, albeit without listing the detailed specimen descriptions and specimen properties that are provided in this report. Y1 - 2018 U6 - https://doi.org/10.4224/23002823 PB - National Research Council of Canada. Construction ER - TY - JOUR A1 - Höller, Christoph A1 - Gibbs, Barry M. T1 - Source substitution method for obtaining the power transmission from vibrating sources in buildings JF - Applied Acoustics N2 - This paper describes a method analogous to the airborne sound source substitution method, to estimate the vibrational power injected by a structure-borne sound source into the supporting building element. The injected vibrational power is required for prediction of the structure-borne sound pressure from vibrating equipment in buildings. The paper focuses on high-mobility sources connected to low-mobility receivers, a situation which is commonly encountered in heavyweight construction. The mobility mismatch simplifies the transformation of laboratory measurement data to prediction of transmitted power in-situ. Three case studies were performed. In the first study, the power injected by a simple test source into a resiliently supported aluminium plate was determined using direct and indirect methods. Source substitution was investigated with different calibration options: steady-state excitation, transient excitation, and spatial averaging. The source power could be determined within 4 dB, compared with direct measurements of the injected power. In the second study, the power injected by a second source into a concrete transmission suite floor was determined. The third study was of a combined heating and power unit on a masonry wall. In this study, a reference sound pressure level in a receiver room was calculated and compared with a criterion curve for the assessment of low-frequency noise complaints. The case studies demonstrate that structure-borne sound source substitution is a promising development of the reception plate method. While the latter can be used if a free reception plate is available, the former circumvents problems of determining the transmitted power into coupled plates and therefore has application to real building conditions. The use of the instrumented hammer for the calibration and the use of spatial averaging significantly simplify the method. Y1 - 2018 U6 - https://doi.org/10.1016/j.apacoust.2018.07.014 VL - 141 SP - 240 EP - 249 PB - Elsevier ER - TY - JOUR A1 - Lievens, Matthias A1 - Höller, Christoph A1 - Dietrich, Pascal A1 - Vorländer, Michael T1 - Predicting the Interaction Between Structure-Borne Sound Sources and Receiver Structures from Independently Measured Quantities BT - Case Study of a Washing Machine on a Wooden Joist Floor JF - Acta Acustica united with Acustica N2 - Structure-borne sound sources are usually characterised by their source activity and source mobility. By combining this data with the mobility of receiver structures it is theoretically possible to predict the sound pressure level in a building. In a case study of a washing machine on a wooden joist floor this prediction process was investigated. The prediction was based on the normal force component only. The contact area at the feet of the washing machine was made as small as possible to avoid the influence of moments while the in-plane components were assumed negligible. These conditions proved to allow for accurate predictions in the coupled state in a previous publication [1]. The results show that the prediction from independently measured normal source and receiver quantities yields large errors below 125 Hz as a consequence of the above assumption. Between 125 and 900 Hz the error of the prediction is within ± 5 dB. The case study further investigated two assumptions frequently encountered in practice: low and high-mobility sources and no cross-coupling between the feet Y1 - 2014 U6 - https://doi.org/10.3813/AAA.918688 VL - 100 IS - 1 SP - 79 EP - 92 PB - European Acoustics Association (EAA) ER - TY - RPRT A1 - Höller, Christoph A1 - Mahn, Jeffrey A1 - Quirt, David A1 - Schoenwald, Stefan A1 - Zeitler, Berndt T1 - Apparent sound insulation in cross-laminated timber buildings N2 - This Report presents the results from experimental studies of airborne sound transmission, together with an explanation of calculation procedures to predict the apparent airborne sound transmission between adjacent spaces in a building whose construction is based on cross-laminated timber (CLT) panels. There are several types of CLT constructions which are commercially available in Canada, but this study only focused on CLT panels that have adhesive between the faces of the timber elements in adjacent layers, but no adhesive bonding the adjacent timber elements within a given layer. There were noticeable gaps (up to 3 mm wide) between some of the timber elements comprising each layer of the CLT assembly. These CLT panels could be called “Face-Laminated CLT Panels” but are simply referred to as CLT panels in this Report. Another form of CLT panels has adhesive between the faces of the timber elements in adjacent layers as well as adhesive to bond the adjacent timber elements within a given layer. These are referred to as “Fully-Bonded CLT Panels” in this Report. Because fully-bonded CLT panels have different properties than face-laminated CLT panels, the sound transmission data and predictions in this Report do not apply to fully-bonded CLT panels. Y1 - 2017 U6 - https://doi.org/10.4224/23002009 PB - National Research Council of Canada. Construction ER - TY - JOUR A1 - Höller, Christoph A1 - Gibbs, Barry M. T1 - Indirect determination of the mobility of structure-borne sound sources JF - Journal of Sound and Vibration N2 - Methods are considered for the indirect determination of the mobility of structure-borne sound sources. Instead of performing measurements on the source in the free state, the source mobility is obtained from measurements made in-situ. This approach is beneficial if the source is difficult to suspend, or if it contains nonlinear structural elements. Two formulations for an indirect source mobility are derived theoretically. The first requires measurement of velocities at or near to the contact points. The second involves measurement of remote velocities only. Neither of the methods requires excitation at the contacts in the coupled state. Numerical simulations of coupled beams are used to validate the two methods and investigate their accuracy and reliability with respect to typical measurement errors, such as background noise and inaccuracies in sensor positioning. It is found that these can have a significant effect on the methods considered. Several experimental case studies with single-contact and multi-contact sources are performed. The results confirm the validity of the two methods in principle, but highlight their sensitivity to experimental errors. In a representative case study with a fan unit, average errors range between ±5 dB and ±10 dB, with occasional errors of up to 30 dB. Y1 - 2015 U6 - https://doi.org/10.1016/j.jsv.2015.01.011 VL - 344 SP - 38 EP - 58 PB - Elsevier ER - TY - JOUR A1 - Höller, Christoph A1 - Gibbs, Barry M. T1 - Inverse Method to Obtain Blocked Forces of Vibrating Sound Sources in Buildings JF - Acta Acustica united with Acustica N2 - Vibrating sources, such as building service equipment, are major contributors to noise in buildings. In order to predict and subsequently reduce the sound pressure levels generated by these devices, it is necessary to first predict the total vibrational power injected by them into the supporting building structure. Whilst simplified methods are available for the calculation of the total power through all contacts, it would be beneficial to have more detailed knowledge of the dominant contact powers. For sources on low-mobility building elements, the contact powers are determined by the blocked force, along with the real part of the receiver mobility at each contact. This paper describes a novel inverse method to obtain the blocked forces at each contact. The method employs an instrumented reception plate, which is numerically modelled to allow optimum accelerometer positions to be selected, for any source and any location. The underlying theory and measurement procedure are described, and experimental validations are presented. Y1 - 2017 U6 - https://doi.org/10.3813/AAA.919092 VL - 103 IS - 4 SP - 639 EP - 649 PB - ingenta ER - TY - RPRT A1 - Mahn, Jeffrey A1 - Quirt, David A1 - Höller, Christoph A1 - Müller-Trapet, Markus T1 - Addendum to RR-335: sound transmission through Nail-Laminated Timber (NLT) assemblies N2 - This report is published as an addendum to NRC Research Report RR-335 “Apparent Sound Insulation in Cross-Laminated Timber Buildings." It is intended that this addendum will be merged with RR-335 in the future as a report for predicting the sound insulation in buildings using mass-timber constructions including NLT assemblies. This report presents the results from experimental studies of airborne sound transmission through assemblies of nail-laminated timber (NLT) with various linings. To put the data presented in this report in the proper context, this report begins with a brief explanation of calculation procedures to predict the apparent sound transmission class (ASTC) between adjacent spaces in a building whose structure is a combination of mass-timber assemblies such as nail-laminated timber (NLT) or cross-laminated timber (CLT) panels. Y1 - 2018 U6 - https://doi.org/10.4224/40000417 PB - National Research Council of Canada. Construction ER - TY - RPRT A1 - Höller, Christoph A1 - Müller-Trapet, Markus A1 - King, Frances A1 - Bradley, John T1 - Evaluation of the communication performance of the C4 chemical, biological, radiological and nuclear mask N2 - The Canadian Armed Forces (CAF) are using chemical, biological, radiological and nuclear (CBRN) general service respirators (GSRs) to defend against CBRN threats and hazards to protect personnel and ensure that they can safely and successfully carry out missions. The CBRN GSR currently in use by the CAF is the C4 respirator. The National Research Council of Canada assessed the communication performance of the C4 respirator. This report presents the results of the performance test. The method for assessing the communication performance used in this study was the NIOSH standard test procedure TEB-CBRN-APR-STP-0313 [1]. Other methods exist to evaluate the communication performance of respirators, but historically the NIOSH standard test procedure has been used. This report details the implementation and results of the tests conducted at the National Research Council of Canada, following the NIOSH standard test procedure. Y1 - 2018 U6 - https://doi.org/10.4224/23003981 ER - TY - RPRT A1 - Höller, Christoph A1 - Quirt, David A1 - Zeitler, Berndt A1 - Sabourin, Ivan T1 - Apparent sound insulation in cold-formed steel-framed buildings N2 - This Report presents the results from substantial experimental studies of sound transmission, together with an explanation of calculation procedures to predict the sound transmission between adjacent spaces in a building whose walls and floors have cold-formed steel (CFS) framing. This first edition contains mainly data for loadbearing steel framing formed from sheet steel with thickness from 1.37 mm (16 gauge) to 0.94 mm (20 gauge). Non-loadbearing CFS studs formed from thinner steel (nominally 0.54 mm) are also commonly used but these are not included in the data tables for sound transmission through wall assemblies in this Report. KW - concrete block walls KW - floor KW - sound insulation KW - sound transmission Y1 - 2017 U6 - https://doi.org/10.4224/23001843 PB - National Research Council of Canada. Construction ER - TY - THES A1 - Höller, Christoph T1 - Indirect methods of obtaining activity and mobility of structure-borne sound sources N2 - The work reported in this thesis focuses on the development of indirect methods for the experimental determination of important source parameters for structure-borne sound source characterization. In the first part of the thesis, matrix inversion methods for the determination of blocked forces are investigated. A simplified measurement procedure is proposed which offers a solution to the two major challenges to these methods, namely the acquisition of the FRF matrix and the problems associated with matrix inversion. The proposed procedure involves a free, low-mobility receiver plate which is modelled numerically. Calculated FRFs are used together with measured velocity responses to inversely determine the blocked forces. It is found that while the method has great potential in principle, in practice the accurate modelling of the receiver plate is of critical importance. In the second part of the thesis, three formulations are considered for the indirect determination of source mobility. Instead of performing measurements on the source in the free state, the source mobility is obtained from measurements made in-situ. This approach is beneficial if the source is difficult to suspend, or if it contains non-linear structural elements. The three formulations are validated numerically and experimentally. It is found that the methods can quantify source mobilities of single-contact and multi-contact sources from in-situ measurements. However, typical measurement errors, such as background noise or inaccuracies in sensor positioning, can significantly reduce the accuracy and reliability of the methods. In the final part of the thesis, the reception plate method for the determination of the power injected by a high-mobility source into a low-mobility receiver is reviewed, and a source substitution method proposed as a development. The substitution method circumvents problems that may arise when the reception plate method is applied to coupled walls and floors. A special focus of investigation is on the calibration of the receiver structure. It is found that the calibration can be performed with shaker or hammer, and that an average calibration factor may be used. The source substitution method thus offers a potential alternative to the reception plate method, for application with coupled plates. Y1 - 2013 UR - https://livrepository.liverpool.ac.uk/id/eprint/14233 N1 - University of Liverpool, Dissertation PB - University of Liverpool CY - Liverpool ER - TY - JOUR A1 - Bauhuber, Michael A1 - Mikrievskij, Andreas A1 - Lechner, Alfred T1 - Isotropic wet chemical etching of deep channels with optical surface quality in silicon with HNA based etching solutions JF - Materials Science in Semiconductor Processing N2 - Online trace analysis based on UV/Vis spectroscopy requires long detection paths. Therefore an isotropic wet etch process in silicon is developed to fabricate a 300 µm deep channel with low channel wall roughness for desired light guidance application. Four etchant compositions were compared in terms of etching rate, surface roughness and selectivity in a beaker process. The best fitting mixture was selected. To further increase the surface quality (bubble issue) a spin etcher tool is used for producing the channels. The dependence of homogeneity and defect density on media flux, and rotation velocity was investigated. Results show that high rotation velocity and high media flux lead to great defects in the channel wall. Through rotation of the wafer during etching, the etching rate of silicon rises compared to the beaker process due to the rapid removal of etch products and simultaneous supply of fresh etchant. After 38 min of etching, 300 µm deep semi-circular channels with high optical quality (Rq=10 nm±2 nm) over 3 m were produced. Y1 - 2013 UR - https://www.scopus.com/authid/detail.uri?authorId=22980567700#disabled U6 - https://doi.org/10.1016/j.mssp.2013.05.017 VL - 16 IS - 6 SP - 1428 EP - 1433 PB - Elsevier ER - TY - CHAP A1 - Höller, Christoph A1 - Zeitler, Berndt T1 - Laboratory study on flanking sound transmission in cold-formed steel-framed constructions T2 - Towards a quieter future : 45th International Congress and Exposition on Noise Control Engineering (Internoise 2016) : Hamburg, Germany, 21-24 August 2016, Vol 8 N2 - In a recent study at the National Research Council Canada, the sound transmission in cold-formed steel-framed constructions was investigated. The results of direct sound insulation tests of wall and floor assemblies were reported at EURONOISE 2015 and INTERNOISE 2015. This paper focuses on flanking sound transmission in cold-formed steel-framed constructions. A representative full-scale mock-up specimen was constructed in NRC’s 8-room flanking transmission facility. The specimen consists of four loadbearing walls with 152 mm deep steel studs, four non-loadbearing walls with 92mm deep steel studs, and four floor-ceiling assemblies consisting of steel joists and a composite steel deck with gypsum concrete. Measurements were conducted according to the indirect method described in ISO 10848. The individual flanking paths were measured by a sequence of transmission loss measurements in which other transmission paths were suppressed by shielding. For the bare specimen without linings, the sound transmission for horizontally adjacent rooms with continuous subfloors is dominated by the floor-floor flanking paths. Floor coverings or floor toppings are needed to meet the requirements in the National Building Code of Canada. This paper presents details of the measurements, highlights some of the results and discusses implications. Y1 - 2016 UR - https://www.researchgate.net/publication/307210627_Laboratory_Study_on_Flanking_Sound_Transmission_in_Cold-Formed_Steel-Framed_Constructions SP - 6238 EP - 6249 PB - Curran Associates Inc. ER - TY - JOUR A1 - Hutterer, Albert A1 - Bauhuber, Michael A1 - Hummel, Helmut A1 - Lechner, Alfred T1 - Real-time analyses of metal contaminations in the ppb-range JF - Solid State Phenomena N2 - In high-tech processing even smallest concentrations of metal ions in process media are of the utmost significance because they cause expensive production failures. Currently, cost-intensive equipment, special trained staff and time consuming analyses are necessary to detect these contaminations in order to avoid failures. The Centers of Excellence Nanochem and Sensorics at the University of Applied Sciences Regensburg (owner of patent PCT/EP2010/064833) and their industrial partner Micro-Epsilon GmbH are developing a new miniaturized measurement device which allows cost-effective real-time analysis of fluidic media for the first time. The system is fully automated and can be directly connected to wet-etch benches. Hence it allows continuous real-time surveillance of metal contaminations in the ppb-range through absorption spectroscopy in process media. For this purpose a very small sample amount of the process medium and a specific complexing agent are mixed together. This leads to an increase in the molar extinction coefficients and though even smallest contaminations become visible. The main parts of our development are the simulation of the different system components, their production and chemical analyses with the evaluation model. KW - Absorption KW - Analysis KW - Complexing Agent KW - Light Guidance KW - Liquid-Core Waveguide KW - Metal Ions KW - Online Measurement KW - Real-Time KW - Total Internal Reflection Y1 - 2013 U6 - https://doi.org/10.4028/www.scientific.net/SSP.195 VL - 195 SP - 269 EP - 273 PB - Trans Tech Publications ER - TY - CHAP A1 - Höller, Christoph A1 - Zeitler, Berndt A1 - Mahn, Jeffrey T1 - Direct sound transmission loss of heavy gauge steel stud walls T2 - Proceedings of Euronoise 2015 : 10th European Congress and Exposition on Noise Control Engineering : Maastricht, 31 May - 3 June 2015 Y1 - 2015 SP - 1121 EP - 1126 CY - Maastricht ER - TY - JOUR A1 - Jungnitsch, Georg T1 - Psychotherapeutische Verfahren bei chronischen Schmerzen JF - Fortschritte der Medizin N2 - Psychotherapeutic possibilities of treating chronic pain are employed in two different ways: Firstly in the form of psychotherapy in patients whose strategies for coping with pain and/or pain genesis can be described in terms of psychopathological categories; secondly in the form of pain-coping training, which is generally indicated in the presence of chronic pain, in particular that which is traditionally termed organic. With respect to their effectiveness in achieving, in the first place, mood change, and in the assessment of symptoms, the individual procedures have been well tested. The question as to differential indication, which can most readily be applied to the use of biofeedback, remains largely unanswered. T2 - Psychotherapeutic possibilities of treating chronic pain Y1 - 1990 UR - https://www.researchgate.net/publication/292930409_Psychotherapeutic_possibilities_of_treating_chronic_pain VL - 108 IS - 8 SP - 50 EP - 58 ER - TY - JOUR A1 - Peter, Daniel A1 - Dalmer, Michael A1 - Lechner, Alfred A1 - Gigler, Alexander M. A1 - Stark, Robert W. A1 - Bensch, Wolfgang T1 - Measurement of the mechanical stability of semiconductor line structures in drying liquids with application to pattern collapse JF - Journal of Micromechanics and Microengineering N2 - Enhanced particle removal processes in wet cleaning as well as drying processes of semiconductor wafers can cause significant lateral forces on surface structures. These forces, however, must not exceed the mechanical stability of structures on the wafer. Thus, a mechanical fracture test was used to assess the lateral mechanical stability of polysilicon line structures in relevant process liquids. The mechanical test was based on nanomanipulation with an atomic force microscope. Compared to fracture tests in air, data acquired in liquid isopropanol revealed a stabilizing effect. The differences in fracture forces can be attributed to a stress corrosion process on the surface. The size of the generated damage was influenced by the viscosity of the surrounding media. Y1 - 2011 U6 - https://doi.org/10.1088/0960-1317/21/2/025001 VL - 21 IS - 2 PB - IOP Science ER - TY - CHAP A1 - Peter, Daniel A1 - Dalmer, Michael A1 - Lotnyk, Andriy A1 - Kienle, Lorenz A1 - Lechner, Alfred A1 - Bensch, Wolfgang T1 - Solid bridging during pattern collapse (stiction) studied on silicon nanoparticles T2 - MRS Online Proceedings Library N2 - The high surface to volume ratio of nanoparticles allows a detailed experimental study of the surface phenomena associated with solid bridging. Besides bulk analyses, the local view on the structure and composition via HRTEM is particularly essential. 50 nm core shell particles consisting of a silicon (Si) core and a SiO2 shell were used as model system to understand surface phenomena appearing for Si-based nanostructures. Evaporative drying from de-ionized water shows the most significant bridging effect based on SiO2. There is only a localized deposition of oxides between the particles during the drying process and no overall oxidation. For the deposition material, silicates are the most likely candidates. Y1 - 2011 U6 - https://doi.org/10.1557/opl.2011.397 VL - 1299 SP - 191 EP - 196 PB - Springer Nature ER - TY - CHAP A1 - Zeitler, Berndt A1 - Höller, Christoph A1 - Mahn, Jeffrey T1 - Empirical model of direct sound transmission through lightweight wood-framed construction T2 - Implementing noise control technology : 44th International Congress and Exposition on Noise Control Engineering (Internoise 2015) : San Francisco, California, USA, 9 - 12 August 2015 N2 - Tools to predict sound transmission through building elements are beneficial from both amarketing and a research standpoint. Prediction models can assist with the optimization ofelement performance and often reduce both cost and time in projects. However, the morephysical phenomena are to be included in the model, the more input data that is needed,which in some cases can be quite time-consuming and costly to collect. A balance is neededbetween the input and modeling effort and the output, which is usually delivered in onethird octave frequency bands or single number ratings. Many different types of models arecommonly used, including analytical, numerical, and empirical are used, all of which haveadvantages and disadvantages. In this paper, the latter type is presented using a set ofphysical properties of lightweight wood elements, and the errors made in the prediction arequantified. The disadvantage of empirical compared to analytical modeling is that thephysical phenomena are more difficult to identify. The advantage is often the simplicityand accuracy of the prediction results. Y1 - 2015 UR - https://www.researchgate.net/publication/281065914_Empirical_Model_of_Direct_Sound_Transmission_through_Lightweight_Wood-Framed_Construction PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Zeitler, Berndt A1 - Mahn, Jeffrey A1 - Sabourin, Ivan A1 - Höller, Christoph A1 - Schoenwald, Stefan T1 - Apparent airborne sound insulation of hybrid wood-concrete masonry assemblies T2 - Euronoise 2015 : 10th European Congress and Exposition on Noise Control Engineering : Maastricht, 31 May - 3 June 2015 N2 - As part of a research project to develop design solutions for concrete-masonry buildings for the Canadian market, the apparent sound insulation performance of hybrid assemblies with concrete masonry walls and wood joist floors was evaluated. In this paper, the effect of junction coupling is investigated in an ISO 15712 flanking prediction context. Airborne flanking path data predicted according to ISO 15712 are compared to data measured using the indirect ISO 10848 shielding method. Recommendations are made on how appropriate the application of ISO 15712 is for this type of hybrid assembly. Y1 - 2015 UR - https://www.conforg.fr/euronoise2015/proceedings/data/articles/000436.pdf SP - 2515 EP - 2520 CY - Maastricht ER -