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排序方式: 共有1367条查询结果,搜索用时 9 毫秒
981.
Leilei Shinohara Julian Asche Tauscher Thorsten Beuth Nico Heussner Maik Fox Harsha Umesh Babu Wilhelm Stork 《Optical Review》2014,21(5):698-704
The control of wind turbine blade pitch systems by Lidar assisted wind speed prediction has been proposed to increase the electric power generation and reduce the mechanical fatigue load on wind turbines. However, the sticking point of such Lidar systems is the price. Hence, our objective is to develop a more cost efficient Lidar system to support the pitch control of horizontal axis wind turbines and therefore to reduce the material requirement, lower the operation and maintenance costs and decrease the cost of wind energy in the long term. Compared to the state of the art Lidar systems, a laser with a shorter coherence length and a corresponding fiber delay line is introduced for reducing the costs. In this paper we present the experimental evaluation of different sending and receiving optics designs for such a system from a free space laboratory setup. 相似文献
982.
Journal of Nanoparticle Research - Co3O4 nanocubes with perfect shape were synthesized by a simple hydrothermal route in which Co3O4 was directly prepared in the one-pot process with aging... 相似文献
983.
Andrew P. Vogt Thomas Tischer Udo Geckle Alexandra M. Greiner Vanessa Trouillet Michael Kaupp Leonie Barner Thorsten Hofe Christopher Barner‐Kowollik 《Macromolecular rapid communications》2013,34(11):916-921
Intrinsically glucoside‐based microspheres are prepared in olive oil via a water in oil inverse suspension polymerization. The microspheres are characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) microscopy, and X‐ray photoelectron spectroscopy (XPS), evidencing the intrinsic glucose character of the spheres. A novel boronic acid fluorescent molecule was subsequently conjugated to the microspheres in an aqueous environment, exhibiting the spatial and uniform distribution of glucoside as well as the affinity of the microspheres to bind with boron, evidenced via fluorescence spectroscopy measurements.
984.
Thorsten W. Jaskolla Michael Karas Udo Roth Kerstin Steinert Christoph Menzel Karsten Reihs 《Journal of the American Society for Mass Spectrometry》2009,20(6):1104-1114
The properties of several cinnamic acid compounds used as matrices for matrix-assisted laser desorption ionization time-of-flight
mass spectrometry (MALDI-TOF MS) were investigated as standard dried droplet (DD) and vacuum sublimed preparations. The differences
between both preparation methods were analyzed with regard to matrix grain size, internal ion energy, initial velocity, analyte
intensity, and analyte incorporation depth. Some of the used cinnamic acid derivatives exhibit clearly reduced grain sizes
as sublimed preparations compared with standard DD approaches. In these cases higher effective temperatures could be measured
accompanied by increased analyte intensities, which can be explained by stronger volatilization processes caused by a hindered
heat dissipation resulting in a raised analyte transfer into the gas phase. For all sublimed compounds, a strong increase
of the initial ion velocity compared with DD preparations could be measured. Higher initial ion velocities correlate with
a decrease in internal ion energy which might be attributed to the very uniform crystal morphology exhibited by sublimed compounds.
For sublimed matrices without reduced grain size, at least slightly higher analyte intensities could be detected at raised
laser fluences. Analyte accumulation in the uppermost matrix layers or the detected higher ion stability can be explanations
for these results. 相似文献
985.
Yoh Matsuki Dr. Thorsten Maly Dr. Olivier Ouari Dr. Hakim Karoui Dr. François Le Moigne Dr. Egon Rizzato Dr. Sevdalina Lyubenova Dr. Judith Herzfeld Prof. Thomas Prisner Prof. Paul Tordo Prof. Robert G. Griffin Prof. 《Angewandte Chemie (International ed. in English)》2009,48(27):4996-5000
A new polarizing agent with superior performance in dynamic nuclear polarization experiments is introduced, and utilizes two TEMPO (2,2,6,6‐tetramethylpiperidine‐1‐oxyl) moieties connected through a rigid spiro tether (see structure). The observed NMR signal intensities were enhanced by a factor of 1.4 compared to those of TOTAPOL, a previously described TEMPO‐based biradical with a flexible tether.
986.
Philipp Selig Dr. Eberhardt Herdtweck Dr. Thorsten Bach Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3509-3525
The stereogenic centers at C3 and C12 of meloscine ( 3 ) can be established in the photochemical key step 1 → 2 . 1,2‐retro‐Benzilic acid rearrangement to a five‐membered ring, reductive amination, Claisen rearrangement, and ring‐closing metathesis are further key steps in the transformation of cyclobutane 2 into the target molecule 3 (14 steps, 9 % overall yield). Enantioselective access to (+)‐meloscine was possible when the [2+2]‐photocycloaddition was conducted in the presence of a chiral template.
987.
988.
Hydroxyethylamine-containing peptides can be sequenced by automated Edman degradation to provide sequence information for peptide segments on either side of the peptide backbone modification. [reaction: see text] 相似文献
989.
990.