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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Rekombinante Hepatitis B Virus Kapside Untersuchungen zur Eignung als ikosahedrale Träger für Strukturuntersuchungen, zur in vitro Assemblierung und Nukleinsäureverpackung /

Vogel, Maren, January 2004 (has links) (PDF)
Stuttgart, Univ., Diss., 2004.
22

Design neuer Sensoren unter Berücksichtigung von Strukturaspekten

Liess, Martin, January 2005 (has links)
Chemnitz, Techn. Univ., Habil.-Schr., [2005].
23

Strukturelle Relaxation von epitaktischen, dünnen La/Sr-Manganitfilmen in Abhängigkeit von der Schichtdicke

Gebhardt, Ulrich Manfred, January 2007 (has links)
Stuttgart, Univ., Diss., 2006.
24

Untersuchungen zur Evolution der (betaalpha) 8 -barrel-Faltung aus (betaalpha) 2 -Modulen

Richter, Markus January 2008 (has links)
Regensburg, Univ., Diss., 2008.
25

Cellulosederivate mit lateralen Übergangsmetall-Chelatkomplexen Synthese und Eigenschaften in verdünnter Lösung /

Laube, Bettina. January 2002 (has links) (PDF)
Darmstadt, Techn. Univ., Diss., 2002.
26

Simsolid: Die neue Generation der Strukturanalyse – komplexeste Simulationen innerhalb weniger Minuten und ohne Vernetzung

Waidmann, Axel 03 July 2018 (has links)
Durch die neue Schweißfunktionalität in Creo 4, welche es ermöglicht Schweißnähte als Volumengeometrie zu modellieren, entstehen viele neue Möglichkeiten zur Berechnung der Spannungen innerhalb der Schweißnähte. Damit einhergehend entstehen neue Möglichkeiten zur Berechnung und Evaluierung dieser Schweißnähte nach den Richtlinien der FKM. Die Berechnung anhand der FKM-Richtlinien soll hierbei anhand der zwei Simulationstools Creo Simulate und Ansys Simulation dargestellt werden.
27

Hypervalent diorganoantimony(III) fluorides via diorganoantimony(III) cations – a general method of synthesis

Preda, Ana Maria, Raţ, Ciprian I., Silvestru, Cristian, Lang, Heinrich, Rüffer, Tobias, Mehring, Michael 18 February 2016 (has links) (PDF)
Novel diorganoantimony(III) fluorides containing ligands with pendant arms, R2SbF (5), (R)PhSbF (6) [R = 2-(2′,6′-iPr2C6H3N[double bond, length as m-dash]CH)C6H4], R′′2SbF (7) and (R′′)PhSbF (8) [R′′ = 2-(Me2NCH2)C6H4], were prepared via the ionic derivatives [R2Sb]+[PF6]− (1), [(R)PhSb]+[PF6]− (2), [R′′2Sb]+[SbF6]− (4) and [(R′′)PhSb]+[SbF6]− (obtained in situ) by treatment with [Bu4N]F·3H2O. The ionic species used as starting materials as well as [R′2Sb]+[PF6]− (3) [R′ = 2-(2′,4′,6′-Me3C6H2N[double bond, length as m-dash]CH)C6H4] were obtained from the corresponding bromides or chlorides and Tl[PF6] or Ag[SbF6]. The compounds were investigated by multinuclear NMR spectroscopy in solution, MS and IR spectroscopy in the solid state. The molecular structures of the ionic species 1·2CH2Cl2 and 3·2CHCl3 as well as of the fluorides 5–8 were determined by single-crystal X-ray diffraction. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
28

Synthesis and characterization of hyperbranched poly(urea-urethane)s / Synthese und Charakterisierung von Hochverzweigte Poly(harnstoff-Urethan)en

Abd Elrehim, Mona Hassan Mohammed 29 June 2004 (has links) (PDF)
The thesis aims to synthesize hyperbranched poly(urea-urethane) polymers (HPU) in one-pot method using commercially available monomers which are 2,4-toluylene diisocyanate (TDI) as aromatic diisocyanate and isophorone diisocyanate (IPDI) and 2(3-isocyanatopropyl) cyclohexylisocyanate (IPCI) as aliphatic diisocyanates. Those proposed diisocyanates were reacted with diethanolamine (DEA) or diisopropanolamine (DIPA). Conditions of polymerisation reactions were optimised. Complete structural analysis using 1H and 13C NMR for the obtained aromatic polymers was carried out. Degree of branching up to 70% was calculated. Aliphatic polymers have spectra with overlapped signals therefore, no full structural analysis was possible. Molar masses were determined using SEC/RI detector which shows that the prepared polymers have Mw values between 1600 g/mol and 106000 g/mol. Thermal analysis for different polymer systems showed that aliphatic HPU are more thermally stable and have values of glass transition temperature higher than aromatic ones. Modification of the end groups in the prepared hyperbranched polymers was carried out using three different modifiers and degree of modification up to 100%. Linear polymers based on the same diisocyanate monomers were prepared to compare the properties of hyperbranched systems with their linear analogs. Measurements of solution viscosity showed that HPU have lower solution viscosity values than their linear analogs of comparable molar masses. Rheological measurement of some polymer samples of different systems were carried out and showed that our hyperbranched systems exhibit a more elastic behavior than the linear polymers. Surface studies for thin films prepared from different polymer systems (hyperbranched, linear and modified) were carried out and the obtained thin films were characterized using light microscope, microglider, GC-MS, and AFM. Contact angle measurements showed that HPU have a relatively hydrophilic character. The modified polymers have higher contact angle values than the unmodified ones due to the lack of OH end groups. Networks based on aliphatic and aromatic HPU were prepared through the reaction of HPU with trimer of 1,6-diisocyanatohexane and characterised by DSC, GC-MS, DMA and AFM. The domain size in aromatic networks was found to be larger than in aliphatic networks. Tensile test was carried out and it was found that aliphatic network is more elastic than aromatic one.
29

Synthesis and characterization of hyperbranched poly(urea-urethane)s

Abd Elrehim, Mona Hassan Mohammed 16 July 2004 (has links)
The thesis aims to synthesize hyperbranched poly(urea-urethane) polymers (HPU) in one-pot method using commercially available monomers which are 2,4-toluylene diisocyanate (TDI) as aromatic diisocyanate and isophorone diisocyanate (IPDI) and 2(3-isocyanatopropyl) cyclohexylisocyanate (IPCI) as aliphatic diisocyanates. Those proposed diisocyanates were reacted with diethanolamine (DEA) or diisopropanolamine (DIPA). Conditions of polymerisation reactions were optimised. Complete structural analysis using 1H and 13C NMR for the obtained aromatic polymers was carried out. Degree of branching up to 70% was calculated. Aliphatic polymers have spectra with overlapped signals therefore, no full structural analysis was possible. Molar masses were determined using SEC/RI detector which shows that the prepared polymers have Mw values between 1600 g/mol and 106000 g/mol. Thermal analysis for different polymer systems showed that aliphatic HPU are more thermally stable and have values of glass transition temperature higher than aromatic ones. Modification of the end groups in the prepared hyperbranched polymers was carried out using three different modifiers and degree of modification up to 100%. Linear polymers based on the same diisocyanate monomers were prepared to compare the properties of hyperbranched systems with their linear analogs. Measurements of solution viscosity showed that HPU have lower solution viscosity values than their linear analogs of comparable molar masses. Rheological measurement of some polymer samples of different systems were carried out and showed that our hyperbranched systems exhibit a more elastic behavior than the linear polymers. Surface studies for thin films prepared from different polymer systems (hyperbranched, linear and modified) were carried out and the obtained thin films were characterized using light microscope, microglider, GC-MS, and AFM. Contact angle measurements showed that HPU have a relatively hydrophilic character. The modified polymers have higher contact angle values than the unmodified ones due to the lack of OH end groups. Networks based on aliphatic and aromatic HPU were prepared through the reaction of HPU with trimer of 1,6-diisocyanatohexane and characterised by DSC, GC-MS, DMA and AFM. The domain size in aromatic networks was found to be larger than in aliphatic networks. Tensile test was carried out and it was found that aliphatic network is more elastic than aromatic one.
30

Geometrie, Aufstiegs- und Deformationsgeschichte von Granit-Gneis-Komplexen im Ostural

Görz, Ines 13 July 2009 (has links) (PDF)
Die Granit-Gneis-Komplexe der Osturalzone stellen juvenile kontinentale Kruste dar, die sich durch Aufschmelzung von Inselbogengesteinen bildete. Voraussetzung dafür war die extreme Verdickung von Inselbogenkruste durch die Stapelung von mehreren Inselbögen bei der Uralorogenese. Die Magmen wurden im postkollisionalen Stadium der Uralorogenese generiert. Bei Aufstieg und Platznahme der Schmelzen wurden Randbereiche der Plutone deformiert. So entstanden Hochtemperatur-Niedrigdruck metamorphe Gneise, die die Granitkörper im Zentrum der Kristallinkomplexe ummanteln und deren Foliation konkordant zum Rand der Granit-Gneis-Komplexe verläuft. Der Intrusionsrahmen wird von ozeanischer Lithosphäre und marinen Sedimenten gebildet. Damit ergibt sich für die Osturalzone ein bisher nicht diskutiertes Szenario: die großvolumige Intrusion stark differenzierter Schmelzen in ozeanische Kruste.

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