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- ItemBeitragsmodell (arXiv)(Berlin : de Gruyter, 2017) Tobschall, EstherAuch nach 25 Jahren ist der E-Print-Server arXiv noch immer eine bedeutende Plattform für die schnelle Veröffentlichung von Forschungsergebnissen und we-sentliche Informationsquelle für seine Fachgebiete. arXiv ist zentrales Fachrepo-sitorium und gilt als Prototyp des Open-Access-Publizierens. Dennoch hat Erfolg auch immer seinen Preis: Dieser Beitrag stellt die Informationsplattform arXiv vor und beschreibt die Erfahrungen mit einem Geschäftsmodell, das über Mit-gliedsbeiträge eine nachhaltige Finanzierung erreichen will.
- ItemChemical composition of the RS CVn-type star lambda andromedae(Berlin : de Gruyter, 2010) Tautvaišiené, G.; Barisevičius, G.; Berdyugina, Svetlana V.; Chorniy, Yuriy; Ilyin, Ilya V.Photospheric parameters and chemical composition are determined for the single-lined chromospherically active RS CVn-type star λ And (HD 222107). From the high resolution spectra obtained on the Nordic Optical Telescope, abundances of 22 chemical elements and isotopes, including such key elements as 12C, 13C, N and O, were investigated. The differential line analysis with the MARCS model atmospheres gives Teff = 4830 K, log g = 2.8, [Fe/H] = -0.53, [C/Fe] = 0.09, [N/Fe] = 0.35, [O/Fe] = 0.45, C/N = 2.21, 12C/13C = 14. The 12C/13C ratio for a star of the RS CVn-type is determined for the first time, and its low value gives a hint that extra-mixing processes may start acting in low-mass chromospherically active stars below the bump of the luminosity function of red giants.
- ItemEIN Portal der TIB (nicht nur) für Ingenieure, Naturwissenschaftler, Informatiker, Mathematiker und Architekten(Berlin : de Gruyter, 2014) Hohlfeld, Michael; Tobschall, EstherDer Beitrag beschreibt zunächst den Ist-Zustand des Zusammenspiels der von der TIB betriebenen Virtuellen Fachbibliotheken sowie dem Fachportal GetInfo. Er gibt einen Ausblick auf ein neues übergreifendes Webportal der TIB, in welchem GetInfo aufgehen wird und welches künftige Fachinformationsdienste der TIB in Form von erweiterten Facheinstiegen anbieten wird – unter Einbindung neuartiger Dienste für Fachcommunities sowie Fachausschnitten der medienspezifischen Portale der TIB.
- ItemDas Goportis-Kompetenzzentrum Lizenzen – ein neuer Player in der deutschen Konsortiallandschaft(Berlin : de Gruyter, 2016) Grisse, Mareike; Oswald, Sindy; Pöche, AlexanderMit jedem Verlag schließen Bibliotheken teils im Alleingang, teils als Konsortium individuelle Lizenzverträge. Die Vielzahl unterschiedlicher Bedingungen, Vertragsklauseln und Preisgestaltungen lassen den „Lizenzwald“ zu einem undurchdringlichen Dschungel werden. Das Goportis-Kompetenzzentrum Lizenzen bündelt Wissen und Erfahrungen der drei Zentralen Fachbibliotheken TIB, ZB MED und ZBW im Bereich Lizenzen, um diese dann anderen Bibliotheken zur Verfügung zu stellen. Dies geschieht in Form eines bundesweiten und fächerübergreifenden Informationsangebotes für Bibliothekarinnen und Bibliothekare und beinhaltet die Verhandlung von Konsortialverträgen sowie vielfältige mit dem Lizenzerwerb und der Lizenzverwaltung verbundene Dienstleistungen
- ItemArchivierung und Publikation von Forschungsdaten: Die Rolle von digitalen Repositorien am Beispiel des RADAR-Projekts(Berlin : de Gruyter, 2016) Kraft, Angelina; Razum, Matthias; Potthoff, Jan; Porzel, Andrea; Engel, Thomas; Lange, Frank; van den Broek, KarinaDisziplinübergreifendes Forschungsdatenmanagement für Hochschulbibliotheken und Projekte zu vereinfachen und zu etablieren – das ist das Ziel von RADAR. Im Sommer 2016 geht mit ‚RADAR – Research Data Repository‘ ein Service an den Start, der Forschenden, Institutionen verschiedener Fachdisziplinen und Verlagen eine generische Infrastruktur für die Archivierung und Publikation von Forschungsdaten anbietet. Zu den Dienstleistungen gehören u. a. die Langzeitverfügbarkeit der Daten mit Handle oder Digital Object Identifier (DOI), ein anpassbares Rollen- und Zugriffsrechtemanagement, eine optionale Peer-Review-Funktion und Zugriffsstatistiken. Das Geschäftsmodell ermutigt Forschende, die anfallenden Nutzungsgebühren des Repositoriums in Drittmittelanträge und Datenmanagementpläne zu integrieren. Publizierte Daten stehen als Open Data zur Nachnutzung wie etwa Data Mining, Metadaten-Harvesting und Verknüpfung mit Suchportalen zur Verfügung. Diese Vernetzung ermöglicht ein nachhaltiges Forschungsdatenmanagement und die Etablierung von Dateninfrastrukturen wie RADAR.
- ItemLinked Heritage – ein europäisches Projekt(Berlin : de Gruyter, 2013) Mensing, PetraDas Hauptziel des EU-Projektes Linked Heritage1 war die Einspielung von 3 Millionen neuen Datensätzen in die Europeana. Die 38 Projektpartner kamen aus 20 europäischen Ländern plus Israel und Russland. Die Technische Informationsbibliothek (TIB) Hannover stellte für dieses Projekt Metadaten aus dem Kompetenzzentrum für nichttextuelle Materialen sowie aus dem Bereich Forschungsdaten bereit und war an drei der sieben Arbeitspakete2 beteiligt.
- ItemCombining multiple statistical methods to evaluate the performance of process-based vegetation models across three forest stands(Berlin : de Gruyter, 2017) Horemans, Joanna A.; Henrot, Alexandra; Delire, Christine; Kollas, Chris; Lasch-Born, Petra; Reyer, Christopher; Suckow, Felicitas; François, Louis; Ceulemans, ReinhartProcess-based vegetation models are crucial tools to better understand biosphere-atmosphere exchanges and eco-physiological responses to climate change. In this contribution the performance of two global dynamic vegetation models, i.e. CARAIB and ISBACC, and one stand-scale forest model, i.e. 4C, was compared to long-term observed net ecosystem carbon exchange (NEE) time series from eddy covariance monitoring stations at three old-grown European beech (Fagus sylvatica L.) forest stands. Residual analysis, wavelet analysis and singular spectrum analysis were used beside conventional scalar statistical measures to assess model performance with the aim of defining future targets for model improvement. We found that the most important errors for all three models occurred at the edges of the observed NEE distribution and the model errors were correlated with environmental variables on a daily scale. These observations point to possible projection issues under more extreme future climate conditions. Recurrent patterns in the residuals over the course of the year were linked to the approach to simulate phenology and physiological evolution during leaf development and senescence. Substantial model errors occurred on the multi-annual time scale, possibly caused by the lack of inclusion of management actions and disturbances. Other crucial processes defined were the forest structure and the vertical light partitioning through the canopy. Further, model errors were shown not to be transmitted from one time scale to another. We proved that models should be evaluated across multiple sites, preferably using multiple evaluation methods, to identify processes that request reconsideration.
- ItemA numerical study on deformation of Newtonian droplets through converging cylindrical dies(Berlin : de Gruyter, 2013) Mostafaiyan, M.; Saeb, M.R.; Ahmadi, Z.; Khonakdar, H.A.; Wagenknecht, U.; Heinrich, G.In this work, the dynamic deformation of a viscose Newtonian droplet passing through cylindrical converging dies has been studied. The changes in the interfacial area between two immiscible Newtonian fluids have been considered as a variable representing the time-dependent deformation of a circular droplet along converging dies. To do so, a surface tracking method has been incorporated into a finite element code, developed by the authors, which quantifies the deformation of the droplet through the converging path, and where the surface area of the deformed drop has been consequently chosen as a criterion for a two-phase interface. In this study, it has been revealed that by changing both rheological and geometrical parameters it is possible to manage the value of interface area between two phases. Ultimately, a unique curve is developed for each droplet to primary phase viscosity ratio which can correlate drop deformation with geometrical parameters.
- ItemPeriodic array-based substrates for surface-enhanced infrared spectroscopy(Berlin : de Gruyter, 2017-7-29) Mayerhöfer, Thomas G.; Popp, JürgenAt the beginning of the 1980s, the first reports of surface-enhanced infrared spectroscopy (SEIRS) surfaced. Probably due to signal-enhancement factors of only 101 to 103, which are modest compared to those of surface-enhanced Raman spectroscopy (SERS), SEIRS did not reach the same significance up to date. However, taking the compared to Raman scattering much larger cross-sections of infrared absorptions and the enhancement factors together, SEIRS reaches about the same sensitivity for molecular species on a surface in terms of the cross-sections as SERS and, due to the complementary nature of both techniques, can valuably augment information gained by SERS. For the first 20 years since its discovery, SEIRS relied completely on metal island films, fabricated by either vapor or electrochemical deposition. The resulting films showed a strong variance concerning their structure, which was essentially random. Therefore, the increase in the corresponding signal-enhancement factors of these structures stagnated in the last years. In the very same years, however, the development of periodic array-based substrates helped SEIRS to gather momentum. This development was supported by technological progress concerning electromagnetic field solvers, which help to understand plasmonic properties and allow targeted design. In addition, the strong progress concerning modern fabrication methods allowed to implement these designs into practice. The aim of this contribution is to critically review the development of these engineered surfaces for SEIRS, to compare the different approaches with regard to their performance where possible, and report further gain of knowledge around and in relation to these structures.
- ItemRecent advances in nano-photonic techniques for pharmaceutical drug monitoring with emphasis on Raman spectroscopy(Berlin : de Gruyter, 2019) Frosch, Timea; Knebl, Andreas; Frosch, TorstenInnovations in Raman spectroscopic techniques provide a potential solution to current problems in pharmaceutical drug monitoring. This review aims to summarize the recent advances in the field. The developments of novel plasmonic nanoparticles continuously push the limits of Raman spectroscopic detection. In surface-enhanced Raman spectroscopy (SERS), these particles are used for the strong local enhancement of Raman signals from pharmaceutical drugs. SERS is increasingly applied for forensic trace detection and for therapeutic drug monitoring. In combination with spatially offset Raman spectroscopy, further application fields could be addressed, e.g. in situ pharmaceutical quality testing through the packaging. Raman optical activity, which enables the thorough analysis of specific chiral properties of drugs, can also be combined with SERS for signal enhancement. Besides SERS, micro- and nano-structured optical hollow fibers enable a versatile approach for Raman signal enhancement of pharmaceuticals. Within the fiber, the volume of interaction between drug molecules and laser light is increased compared with conventional methods. Advances in fiber-enhanced Raman spectroscopy point at the high potential for continuous online drug monitoring in clinical therapeutic diagnosis. Furthermore, fiber-array based non-invasive Raman spectroscopic chemical imaging of tablets might find application in the detection of substandard and counterfeit drugs. The discussed techniques are promising and might soon find widespread application for the detection and monitoring of drugs in various fields.
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