148 research outputs found
Exploring circularity in ceramic 3D printing: Possibilities and implementation
No full textNowadays, concepts such as recycling, reusing, and sustainability are gaining ground in a wide range of fields and sectors, including manufacturing. This paradigm shift from “produce-dispose” to “produce-reuse” is pushing manufacturers and producers to move from a linear economy to a circular one. This change in perspective seems more readily applicable to the world of additive manufacturing, as it offers the potential not only to reduce waste generation, but also to reintroduce discarded and recycled materials into the production chain. This implementation of a circular manufacturing approach could be applied to ceramic additive manufacturing. Is it a straightforward process to implement a circular solution into the production chain? Which are the implications for costs, energy requirements, emissions, and waste management? This open discussion aims to identify potential starting points and gaps for further evaluation of future application of circular economy concepts in the ceramic industry
Recyclability of ceramic powder in CerAM vat photopolymerization
No full textThe sustainability of the manufacturing industry is becoming an increasingly hot topic, particularly the reintroduction of waste into the production chain. The use of AM of ceramics can reduce waste and enable complex,
lightweight designs, however, practical routes to circularity remain underdeveloped. This investigation aims to
explore the potential of coupling these additive fabrication techniques with raw materials from alternative
sources of ceramics, such as printing wastes and error prints, developing a photocurable ceramic suspension for
DLP technology. For resin preparation, a polymeric premix was first prepared by combining a mixture of
different acrylate monomers as a photoreactive binder with a non-reactive plasticizing additive. Alumina was
recovered from failed green bodies following matrix burning out, parts grinding and sieving of the obtained
powder. Subsequent investigations of the powder by SEM imaging and EDX analysis were carried out to verify
particle morphology and average dimensions and to identify any contaminants in the recycled material. The
suspension viscosity and curing behaviour were measured. Finally, the mechanical characteristics of printed
parts, their density, their shrinkage, as well as possible contaminants, were evaluated, in order to understand the
impact of the recycling process on material performances and to determine its possible application fields. Tests
results provided a practical recycling potential for alumina in DLP, offering viable solutions in facilitating closedloop CerAM manufacturing
Loan supply in Germany during the financial crisis
No full textDistinguishing pure supply effects from other determinants of price and quantity in the market for loans is a notoriously difficult problem. Using German data, we employ Bayesian vector autoregressive models with sign restrictions on the impulse response functions in order to enquire the role of loan supply and monetary policy shocks for the dynamics of loans to non-financial corporations. For the three quarters following the Lehman collapse, we find very strong negative loan supply shocks, while monetary policy was essentially neutral. Nevertheless, the historical decomposition shows a cumulated negative impact of loan supply shocks and monetary policy shocks on loans to non-financial corporations, due to the lagged effects of past loan supply and monetary policy shocks. However, these negative effects on loans to non-financial corporations are overcompensated by positive other shocks, which implies that loans developed more favorably than implied by the model, over the past few quarters. --Loan supply,Bayesian VAR,sign restrictions
Improved sputter depth resolution in Auger thin film analysis using in situ low angle cross-sections
No full textExperimental setups for XPS measurements beyond the instrumental lateral resolution limit
No full text
Qualifizierung des Polysulfon-Verfahrens für die Herstellung (dichter) keramischer Formkörper
No full textDas Phaseninversionsverfahren auf Basis von Polysulfon, N-Methyl-Pyrrolidon und Wasser zeichnet sich durch eine Prozessführung bei Raumtemperatur und geringen apparativen Aufwand aus. Für die Herstellung von polymeren und keramischen Filtrationsmembranen optimiert, ist die Ausbildung einer ausgeprägten Porosität charakteristisch. Innerhalb der vorliegenden Arbeit wurde das Verfahren durch eine systematische Untersuchung der Einflussparameter auf die Porenbildung für die Herstellung von dichten keramischen Formkörpern qualifiziert. Dabei lag der Fokus auf der Herstellung piezokeramischer Fasern. Die gewonnen Erkenntnisse flossen in eine optimierte Anlagen- und Prozesstechnik ein, mit denen die Herstellung von Fasern mit bisher unerreichten Eigenschaften möglich ist
Status monitoring of ion sputter relevant parameters of an XPS depth profiling instrument
No full textModellgestützte Konzeption und Aufbau eines Demonstrators für neuartige keramische fluidische Mischerstrukturen durch Folientechnologie
No full text1 Einleitung // 2 Grundlagen und Stand der Technik / 2.1 Statische Mischer / 2.2 Katalysatorträgerstrukturen / 2.3 Keramische Mehrlagentechnologie (Foliengießen) / 2.4 Additive Fertigung von Keramik (LCM) / 2.5 Numerische Strömungsmechanik (CFD) // 3 Arbeiten zur Modellierung und Strömungssimulation / 3.1 Konzept einer neuartigen Mischerstruktur / 3.2 Entwicklung eines 3D-CAD-Modells / 3.3 Entwicklung eines 3D-CFD-Modells / 3.4 Fehlerbetrachtung und Netzstudien / 3.5 Variationsanalysen zum Strömungs- und Mischungsverhalten // 4 Experimentelles / 4.1 Fertigung von Mischerstrukturen mittels keramischen Foliengießen / 4.2 Fertigung eines Demonstrators mittels LCM // 5 Zusammenfassung und Ausblic
Verbesserung der MALDI-TOF-basierten Identifizierung humanpathogener Pilze durch die Erstellung individueller Datenbanken
No full textDer Nachweis von seltenen Pilzspezies mittels MALDI-TOF Massenspektronomie ist dadurch limitiert, dass die kommerziellen Datenbanken lückenhaft, oder die Aufbereitungsprotokolle in der Routinediagnostik aufwendig sind. Die vorliegende Dissertation, die aus drei Publikationen besteht zeigt auf, dass es möglich ist mit einfachen Mitteln eigene Datenbanken zu erstellen, die diese Lücken schließen, oder Arbeitsprozesse vereinfachen.
In der ersten Publikation „Yeast On-Target Lysis (YOTL), a Procedure for Making Auxiliary Mass Spectrum Data Sets for Clinical Routine Identification of Yeasts” zeigen wir, wie mittels einer minimalen Datenbank aus 6 Referenzspektren eines vereinfachten Probenaufarbeitungsprotokoll die Arbeit in der Routinediagnostik vereinfacht werden könnte.
Die zweite Publikation „Towards proteomic species barcoding of fungi - an example using Scedosporium /Pseudallescheria genus isolates” beschreibt das Herstellen einer Datenbank mit Isolaten aus dem Scedosporien/Pseudallescheria-Komplex, die auch in der klinischen Routine anwendbar ist.
In der dritten Publikation „CryptoType – datasets for MALDI-TOF based differentiation of Cryptococcus neoformans/gattii complex isolates” haben wir ein Datenset aus 13 Referenzspektren für den Biotyper MALDI-TOF MS erstellt, welches aus den sieben anerkannten nicht-hybriden Subtypen in den Cryptococcus neoformans / gattii-Komplexen besteht. Diese Subtypisierung war bisher mit den kommerziellen Datenbanken nicht möglich, hier konnten wir aufzeigen, dass selbsterstellte Datenbanken Lücken der kommerziellen Datenbanken schließen können.
Diese drei Publikationen sollen zeigen, welches Potential zur Verbesserung der Identifikation seltener Pilzspezies die Erstellung eigener, auf die eigenen Bedürfnisse angepassten Datenbaken steckt.The identification of rare fungal species using MALDI-TOF mass spectrometry is limited by the fact that commercial databases are incomplete or the preparation protocols in routine diagnostics are complex. This dissertation, which consists of three publications, shows that it is possible to use simple means to create your own databases that can close these gaps or can simplify work processes.
In the first publication “Yeast On-Target Lysis (YOTL), a Procedure for Making Auxiliary Mass Spectrum Data Sets for Clinical Routine Identification of Yeasts” we show how a simplified sample processing protocol using a minimal database of 6 reference spectra simplifies the work in routine diagnostics could become.
The second publication “Towards proteomic species barcoding of fungi - an example using Scedosporium / Pseudallescheria genus isolates” describes the creation of a database with isolates from the Scedosporia / Pseudallescheria complex, which can also be used in clinical routine.
In the third publication “CryptoType – datasets for MALDI-TOF based differentiation of Cryptococcus neoformans/gattii complex isolates” we created a dataset of 13 reference spectra for the Biotyper MALDI-TOF MS, which consists of the seven recognized non-hybrid subtypes in the Cryptococcus neoformans / gattii complexes. This subtyping was previously not possible with commercial databases, but here we were able to show that self-created databases can close gaps in commercial databases.
These three publications are intended to show the potential for improving the identification of rare fungal species by creating your own databases tailored to your own needs.2023-12-1
- …
