Three of the six possible stereoisomers of dodecahydroacenaphthylene, f,t,t-ufolane (l), c,c,f-ufolane (3), and c,c,c-ufolane The names derived from the IUPAC nomenclature rules for the six possible stereoisomers 1 -6 are quite long. Therefore, we propose the following simple notation: For the dodecahydroacenaphthylenes with trans-linkage of all rings, viz. for 1, we have already proposed the name "ufolane"['ol. This name will now be used for all stereoisomers of dodecakydroacenapktkylene. For the notation of the configuration we follow the rules of Landa and Vanek?1. The molecules are drawn in such a way that the fivemembered ring is at the top.2. The hydrogen at the central tertiary carbon atom lies above the paper.3. The relation of the carbon -hydrogen bond at the central tert. carbon atom to the carbon-hydrogen bonds at the other tert. carbon atom is characterized as cis or trans, beginning with C-1 (unsystematic numbering) and continuing clockwise.4. In addition to the rules of Landa and Vanek@] we propose: If there are two possibilities following rule 3 the direction is: cis precedes trans, e.g. the correct name for 3 will be rac-cis,cis,trans-ufolane or -abbreviated -rac-c,c,tufolane and not rac-trans,cis,cis-ufolane (rac-t,c,c-ufolane) as drawn in 3a, if the racemate and not a specific enantiomer is to be indicated.c,c,c-Ufolane (5) seems to be the most valuable isomer with respect to its use as a propellant because of its high mass density.Vanek et aLc6] showed that five isomers are formed by catalytic hydrogenation of acenaphthene; the authors separated them by thermodiffusion and isolated one by preparative GC. The isomers were characterized by means of their G C retention indicesr5a6]. Furthermore, the assignment of the structure of the five isomers was attempted on the basis of their 13C-NMR spectral"] or of the G C retention indices on columns with graphitized thermal carbon black['*'. However, an unequivocal structural assignment was still lacking. We describe here the synthesis of the three stereoisomers 1, 3, and 5. Scheme IChem.
Since the introduction of new search engine-based library catalogues and resources discovery systems, users have been able to find millions of online documents that are available in parallel to local holdings. Users of these new, continually expanding catalogue systems need to be able to find titles in a convenient way. The quality of recommendation systems and especially relevance ranking methods is very important for the success of discovery catalogues. Up to now, library catalogue ranking methods have largely ignored user feedback. However, in 2011, the State and University Library Bremen (SuUB) developed modified ranking methods for its own discovery system, Electronic Library Bremen (E-LIB Bremen). These make use of popularity factors such as click statistics and information about the number of editions published as well as how many copies of a given title are available. This customized development has enabled fast and flexible new retrieval functions to meet the needs of local users.
The State and University Library Bremen (SuUB) is dedicated to the digitization of its historical collections. Digitization is an important instrument for improving the accessibility of valuable information contained in fragile historical documents. It facilitates academic research and teaching and is indispensable to the digital humanities. Especially the research of digital serial publications benefits from ‘recent systematic digitization efforts, often initiated by libraries […]. More and more historical periodicals and other serial publications are now digitally available in full, i.e., all of their issues’ [Piotrowski, this volume]. The historical journal presented in this article is one of these and the final section will discuss why it can be considered a complete corpus. Usually, digitization projects produce digital images, metadata for cataloguing and web-navigation purposes and OCR full text for searching. This information is made available through the library's web portal for digital collections. However, digital humanists need high-quality full texts enriched with metadata in the appropriate format to analyse them with powerful software tools. The historical journal Die Grenzboten serves as an exemplary model to bridge the gap between digitization projects in libraries and research infrastructures. Die Grenzboten is a long running serial publication (1841 – 1922). It can be classified as a literary journal that also covered politics and arts. We demonstrate that OCR post correction and a page-wise structuring are prerequisites for the creation of a high-quality TEI version of a full text. The TEI version was created in cooperation with the Deutsches Textarchiv (DTA) at the Berlin-Brandenburg Academy of Sciences and Humanities (BBAW). A fully automated OCR post correction developed at the SuUB Bremen is freely available on GitHub. To enable scientists to work with powerful software tools the transfer of high-quality full texts to research infrastructures is a necessary step. We describe transfers of full text and the experience we have made, but still some general questions persist: What has to be done to prepare raw OCR output for this purpose in a reasonable and cost-effective manner? What quality is needed or expected? Which metadata and file formats are needed? Should there not be a closer cooperation between research infrastructures and libraries handling the digitization? OCR full texts, even post corrected, are not perfect but character recognition rates around 99% certainly provide more options than just being used as a search index. There is a vast amount of textual resources available ready to be made fully accessible for scientific research! Finally, some suggestions for scholars and the researchers working on digital serial publications are given.
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