DBIS – Eine erfolgreiche Kooperation in die Zukunft führen

Mit dem Datenbank-Infosystem (DBIS) arbeiten kooperativ weit über 300 Bibliotheken. DBIS stellt somit einen wichtigen Teil der deutschsprachigen wissenschaftlichen Informationsinfrastruktur dar. Diese Infrastruktur wird immer internationaler und moderner, was neue Anforderungen an DBIS mit sich bringt. In einem von der DFG geförderten Projekt soll DBIS daher umfassend modernisiert werden. Dafür wurden an der Universitätsbibliothek Regensburg zunächst verschiedene Formen des User Experience (UX) Research, also der Forschung zu Erfahrungen mit DBIS und zur Nutzung der Plattform, durchgeführt. Dieser Artikel stellt insbesondere die Methodik des UX Research vor und stellt diese in den Zusammenhang des DBIS-Projekts und dessen Weg in die Zukunft.  The Database Information System (DBIS) is used by well over 300 institutions. It is therefore an important part of the German information infrastructure. This infrastructure is becoming more and more international and modern, which brings new requirements for DBIS. Therefore, DBIS will be comprehensively modernized in a project funded by the DFG. To this end, various forms of user experience (UX) research, i.e., research on experiences with DBIS and on the use of the platform, were conducted at Regensburg University Library. This article introduces the UX research methodology in particular, and places it in the context of the DBIS project and its plans for its future.

A Crowdsourced Approach for the Documentation and Transcription of Graffiti in Public Restrooms

In this short paper we introduce graffiti in public restrooms – also known as latrinalia – as a promising object of research. We present an application that uses crowdsourcing techniques to upload and transcribe images of latrinalia on a public web site. This article describes the basic design and functions of the application, presents the status quo of the current dataset, and also gives an outlook on the next steps and future work

Di-Zinc-Aryl Complexes: CO2 Insertions and Applications in Polymerisation Catalysis

Two new di-zinc aryl complexes, [LZn2Ph2] and [LZn2(C6F5)2], coordinated by a diphenol tetraamine macrocyclic ligand are prepared and fully characterized, including by single crystal X-ray diffraction experiments. The complexes’ reactivities with monomers including carbon dioxide, cyclohexene oxide, phthalic anhydride, iso-propanol and phenol are investigated using both experimental studies and density functional theory calculations. In particular, [LZn2Ph2] readily inserts carbon dioxide to form a carboxylate, at 1 bar pressure, whereas [LZn2(C6F5)2] does not react. Under these conditions [LZn2Ph2] shows moderate activity in the ring-opening copolymerisation of cyclohexene oxide / carbon dioxide (TOF = 20 h-1); cyclohexene oxide / phthalic anhydride (TOF = 33 h-1) and the ring opening polymerisations of rac-lactide (TOF = 99 h-1) and ε-caprolactone (TOF = 5280 h-1)

Heterodinuclear titanium/zinc catalysis: synthesis, characterization and activity for CO2/epoxide copolymerization and cyclic ester polymerization

The preparation of heterodinuclear complexes, especially those comprising early-late transition metals coordinated by a simple or symmetrical ancillary ligand, represents a fundamental challenge and an opportunity to prepare catalysts benefitting from synergic properties. Here, two new mixed titanium(IV)-zinc(II) complexes, [LTi(OiPr)2ZnEt] and[LTi(OiPr)2ZnPh], both coordinated by a diphenolate tetra(amine) macrocyclic ligand (L), are prepared. The synthesis benefits from the discovery that reaction of the ligand with a single equivalent of titanium tetrakis(iso-propoxide) allows the efficient formation of a mono-Ti(IV) complex, [LTi(OiPr)2]. All new complexes are characterized by a combination of single crystal X-ray diffraction, multinuclear NMR spectroscopy and mass spectrometry techniques. The two heterobimetallic complexes, [LTi(OiPr)2ZnEt] and [LTi(OiPr)2ZnPh], feature trianionic coordination by the macrocyclic ligand and bridging alkoxide groups coordinate to both the different metal centres. The heterodinuclear catalysts are compared to the mono-titanium analogue, [LTi(OiPr)2], in various polymerization reactions. In the alternating copolymerizations of carbon dioxide and cyclohexene oxide, the mono-titanium complex is totally inactive whilst the heterodinuclear complexes show moderate activity (TOF = 3 h-1); it should be noted the activity is measured using just 1 bar pressure of carbon dioxide. In the ring opening polymerization of lactide and ε-caprolactone, the mono-Ti(IV) complex is totally inactive whilst the heterodinuclear complexes show moderate-high activities, qualified by comparison to other known titanium polymerization catalysts (L-lactide, kobs = 11 x 10-4 s-1 at 70 °C, 1 M in [lactide]) and ε-caprolactone (kobs = 5 x 10-4 s-1 at 70 °C, 0.9 M in [ε-caprolactone])

Advances in heterometallic ring-opening (co)polymerisation catalysis

Truly sustainable plastics require renewable feedstocks coupled with efficient production and end-of-life degradation/recycling processes. Some of the most useful degradable materials are aliphatic polyesters, polycarbonates and polyamides, which are often prepared via ring-opening (co)polymerisation (RO(CO)P) using an organometallic catalyst. While there has been extensive research into ligand development, heterometallic cooperativity offers an equally promising yet underexplored strategy to improve catalyst performance, as heterometallic catalysts often exhibit significant activity and selectivity enhancements compared to their homometallic counterparts. This review describes advances in heterometallic RO(CO)P catalyst design, highlighting the overarching structure-activity trends and reactivity patterns to inform future catalyst design

Historische Wetterdaten im Spannungsfeld von OCR und UCD

Dieser Beitrag beschreibt informatische Herausforderungen im Kontext eines Digital Humanities-Projekts zur Erschließung und Analyse historischer Wetteraufzeichnungen im Zeitraum 1774 - 1827. Bei der Erschließung der handschriftlichen Aufzeichnungen, die Besonderheiten wie numerische Messwerte in Tabellenstruktur und überlagernde Notizen enthalten, soll langfristig ein entsprechend trainierter OCR-Ansatz (optical character recognition) zum Einsatz kommen. Für die Erstellung entsprechender Trainingsdaten sowie für die manuelle Korrektur der automatisch erkannten Daten ergeben sich zunächst softwareergonomische Herausforderungen aus Perspektive der Medieninformatik. Der Fokus dieses Beitrags liegt daher auf der Erstellung von Tools unter Berücksichtigung von Prinzipien des usability engineering und des user-centered design (UCD) für geisteswissenschaftliche Forschungsvorhaben