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991.
Markus Winkler Katrin Steinke Ramona Oehme Stefan Berger Dieter Sicker Hans‐Ullrich Siehl Klaus‐Peter Zeller 《Chemie in Unserer Zeit》2014,48(3):190-199
Raffinose has been obtained by extraction with 50% ethanol from the seeds of the Sweet Blue Lupine and purified first via a Cation exchange column and finally by analytical HPLC using a RI‐detector. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
992.
Georg Ramer Jürgen Kasberger Markus Brandstetter Ahmed Saeed Bernhard Jakoby Bernhard Lendl 《Applied physics. B, Lasers and optics》2014,116(2):325-332
We present the design and fabrication of a single-mode slab waveguide structure for mid-infrared spectroscopy optimized for broadband coupling. The sensor uses grating couplers for robust off-axis coupling and a silicon nitride guiding layer for mechanical robustness. An external cavity quantum cascade laser-based transmission method is introduced for characterizing the structure’s broadband coupling behavior. Light from an external cavity quantum cascade laser with a spectral range of 0.5 μm around 6 μm was coupled into the waveguide without the need for moving parts. First spectra taken with this sensor are presented. 相似文献
993.
Jiaan Zheng Wataru Kobayashi Thomas Hamann Daniel Nürenberg Markus Lührmann Johannes A. L’huillier Richard Wallenstein Helmut Zacharias 《Applied physics. B, Lasers and optics》2014,116(3):549-560
We present a visually intuitive method for higher-order dispersion compensation based on multi-photon interpulse interference pulse scans. The dispersion values obtained from these scans are fed back as a correction to an acousto-optical programmable dispersive filter to compensate residual higher-order dispersions up to fifth order. This method is applied to the dispersion management of a non-collinear optical parametric chirped-pulse amplifier. A grism-pair stretcher is designed based on a global dispersion balance which provides a large stretching factor and supports a spectral bandwidth of up to 320 nm. It is implemented in a two-stage three-pass non-collinear optical parametric chirped-pulse amplifier and stretches 6-fs seed pulses to about 80 ps from 700 to 1,000 nm. The amplified pulses are compressed by material dispersion. Pulses of less than 10-fs duration with a pulse energy of 125 μJ are obtained at 20-kHz repetition rate. 相似文献
994.
Directed evolution of high-affinity antibody mimics using mRNA display 总被引:11,自引:0,他引:11
Xu L Aha P Gu K Kuimelis RG Kurz M Lam T Lim AC Liu H Lohse PA Sun L Weng S Wagner RW Lipovsek D 《Chemistry & biology》2002,9(8):933-942
We constructed a library of >10(12) unique, covalently coupled mRNA-protein molecules by randomizing three exposed loops of an immunoglobulin-like protein, the tenth fibronectin type III domain (10Fn3). The antibody mimics that bound TNF-alpha were isolated from the library using mRNA display. Ten rounds of selection produced 10Fn3 variants that bound TNF-alpha with dissociation constants (K(d)) between 1 and 24 nM. After affinity maturation, the lowest K(d) measured was 20 pM. Selected antibody mimics were shown to capture TNF-alpha when immobilized in a protein microarray. 10Fn3-based scaffold libraries and mRNA-display allow the isolation of high-affinity, specific antigen binding proteins; potential applications of such binding proteins include diagnostic protein microarrays and protein therapeutics. 相似文献
995.
The European Physical Journal E - Many types of motile cells perform durotaxis, namely directed migration following gradients of substrate stiffness. Recent experiments have revealed that cell... 相似文献
996.
EV Johnston O Verho MD Kärkäs M Shakeri CW Tai P Palmgren K Eriksson S Oscarsson JE Bäckvall 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(39):12202-12206
Palladium nanoparticles immobilized on amino-functionalized mesocellular foam constitute an efficient catalyst for the aerobic oxidation of primary and secondary alcohols to their corresponding carbonyl compounds in high to excellent yields. An exceptionally high TON of 365?000 was reached for the oxidation of 1-phenylethanol under solvent-free reaction conditions. The catalyst can be recycled many times with retained activity as shown by the identical rate curves of the first and fifth runs. 相似文献
997.
Diynyl-substituted bromoarenes underwent a novel Pd-catalyzed domino reaction to provide benzofurans, pyridinofurans, isochromenes, and indole derivatives. Slight changes of the substrate push the reaction in another direction resulting in benzene annulation. 相似文献
998.
Owing to the increasing number of erythropoietin biosimilars being approved, the comparison of different erythropoietin preparations
in the pharmaceutical area is gaining in importance. Erythropoietin has a distinct natural heterogeneity arising from its
glycosylation, which shows strong composition variations. This heterogeneity increases the complexity of the analysis of erythropoietin
considerably, but may also be used to distinguish different preparations. Here, a method is presented for the differentiation
of various erythropoietin preparations by capillary electrophoresis–mass spectrometry and the subsequent application of multivariate
statistics. Relative peak areas of selected intact erythropoietin isoforms were used as variables in principal component analysis
and hierarchical agglomerative clustering. Both of these strategies were suited for the clear differentiation of all erythropoietin
preparations, including marketed products and preproduction preparations, which differ in the manufacturer, the production
cell line, and the batch number. By this means, even closely related preparations were distinguished on the basis of the combined
information on the antennarity, the sialoform, and the acetylation of the observed isoforms. 相似文献
999.
1000.