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91.
Felix M. Pasker Michael F. G. Klein Monamie Sanyal Esther Barrena Uli Lemmer Alexander Colsmann Sigurd Höger 《Journal of polymer science. Part A, Polymer chemistry》2011,49(23):5001-5011
The synthesis, characterization, and photovoltaic properties of a series of four conjugated polymers containing 2‐aryl‐2H‐benzotriazoles and “bis(thiopheno)dialkylfluorenes” is described. The polymers were obtained via Suzuki‐polycondensation and comprise alternating electron rich and electron poor building blocks. The impact of systematic structural changes on the electronic and morphological properties and device efficiencies were studied. Application of these polymers as light‐harvesting and electron‐donating materials in organic solar cells using PCBM derivatives as electron accepting materials resulted in power conversion efficiencies up to 1.8%. Both the properties of the pristine polymers and the device performance show that the impact of the substitution farther‐off the backbone is negligible while substitution directly on the backbone has a major impact. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
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93.
Dr. Antony J. Williams Taye B. Demissie Dr. Espen Hansen Dr. Jeanette H. Andersen Dr. Johan Svenson Kirill Blinov Dr. Michal Repisky Dr. Fabian Mohn Dr. Gerhard Meyer Prof. Dr. John‐Sigurd Svendsen Prof. Dr. Kenneth Ruud Prof. Dr. Mikhail Elyashberg Dr. Leo Gross Prof. Dr. Marcel Jaspars Dr. Johan Isaksson 《Angewandte Chemie (International ed. in English)》2012,51(49):12238-12241
94.
95.
Bartholomaeus Pieber Sigurd SchoberChristoph Goebl Martin Mittelbach 《Journal of chromatography. A》2010,1217(42):6555-6561
A new method was developed for the quantitative analysis of steryl glycosides in biodiesel (fatty acid methyl esters). This method is much more sensitive than existing methods and has minimum limits of quantification of 50 μg/kg, compared to previously published minimum limits of quantification of about 15 mg/kg. The analysis is based on gas chromatography–mass spectroscopy determination of simple pre-treated and silylated samples via single ion monitoring at 147, 204, 217 m/z, which are specific ions for the silylated sugar moiety. Quantification was carried out using cholesteryl β-d-glucopyranoside as internal standard. The modified synthesis and purification of the internal standard is also presented as well as the characterization by NMR and mass spectroscopy. The advantage of the method compared with other approaches is the simplified sample preparation avoiding extra pre-treatment steps coupled with complete derivatization of the sugar hydroxyl groups by using N,O-bis(trimethylsilyl)acetamide with 5% trimethylchlorosilane as derivatization reagent. On the given conditions high recovery rates ≥89% can be obtained. Evaluation of lab specific variance and intermediate precision underline the robustness of the method which will be further assessed by Round robin tests. 相似文献
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97.
Ane Funderud Heidi H Henanger Tilahun T Hafte Paul S Amieux Sigurd Ørstavik Bjørn S Skålhegg 《BMC biochemistry》2006,7(1):1-10
Background
SCF ubiquitin ligases target numerous proteins for ubiquitin dependent proteolysis, including p27 and cyclin E. SCF and other cullin-RING ligases (CRLs) are regulated by the ubiquitin-like protein Nedd8 that covalently modifies the cullin subunit. The removal of Nedd8 is catalyzed by the Jab1/MPN domain metalloenzyme (JAMM) motif within the Csn5 subunit of the Cop9 Signalosome. 相似文献98.
Jester SS Schmitz D Eberhagen F Höger S 《Chemical communications (Cambridge, England)》2011,47(31):8838-8840
Rigid rod oligo(phenylene-ethynylene-butadiynylene)s (oPEBs), "half-rings" of two rigid rods connected via a molecular clamp unit, and shape-persistent macrocycles (cyclic "half-ring dimers") are synthesized and their self-assembled monolayers (SAMs) are investigated by scanning tunneling microscopy (STM) at the interface of 1,2,4-trichlorobenzene (TCB)/highly oriented pyrolytic graphite (HOPG). The results are important for the design of molecular building blocks for two-dimensional nanoscale architectures on solid surfaces. 相似文献
99.
Takeshi Saito Sigurd Wenner Elisa Osmundsen Calin D. Marioara Sigmund J. Andersen Jostein Røyset 《哲学杂志》2013,93(21):2410-2425
Effects of addition of Zn (up to 1 wt%) on microstructure, precipitate structure and intergranular corrosion (IGC) in an Al–Mg–Si alloys were investigated. During ageing at 185?°C, the alloys showed modest increases in hardness as function of Zn content, corresponding to increased number densities of needle-shaped precipitates in the Al–Mg–Si alloy system. No precipitates of the Al–Zn–Mg alloy system were found. Using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), the Zn atoms were incorporated in the precipitate structures at different atomic sites with various atomic column occupancies. Zn atoms segregated along grain boundaries, forming continuous film. It correlates to high IGC susceptibility when Zn concentration is ~1wt% and the materials in peak-aged condition. 相似文献
100.
Abstract The lattice disorder produced in germanium by 56keV boron-ion bombardment has been measured using the channeling-effect technique. The dependence on dose (1014-1016 ions/cm2) and implantation temperature (?90 °C to +130°C) has been studied. It is found that at room-temperature, each incident boron ion creates ?10 times more disorder in germanium than in silicon. It is remarked that, contrary to the present results, previously established anneal stages generally occur at significantly lower temperatures in germanium than in silicon. 相似文献