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31.
Shyjumon Ibrahimkutty Daniel Issenmann Stefan Schleef Anke‐Susanne Müller Yves‐Laurent Mathis Biliana Gasharova Erhart Huttel Ralph Steininger Jörg Göttlicher Tilo Baumbach Albrecht Bartels Christof Janke Anton Plech 《Journal of synchrotron radiation》2011,18(4):539-545
A high‐repetition‐rate pump–probe experiment is presented, based on the asynchronous sampling approach. The low‐α mode at the synchrotron ANKA can be used for a time resolution down to the picosecond limit for the time‐domain sampling of the coherent THz emission as well as for hard X‐ray pump–probe experiments, which probe structural dynamics in the condensed phase. It is shown that a synchronization of better than 1 ps is achieved, and examples of phonon dynamics of semiconductors are presented. 相似文献
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Noble C. Woo Kunigunde Cherenack Gerhard Tr?ster Ralph Spolenak 《Applied Physics A: Materials Science & Processing》2010,100(1):281-285
Reducing the strain in brittle device layers is critical in the fabrication of robust flexible electronic devices. In this
study, the cracking behavior of micro-patterned 500-nm-thick Ti films was investigated via uniaxial tensile testing by in
situ SEM and 4-point probe measurements. Both visual observations by SEM and 4-pt resistance measurements showed that strategically
patterned oval holes, off-set and rotated by 45°, had a significant effect on limiting the extent of cracking, specifically,
in preventing cracks from converging. Failure with regard to electrical conduction was delayed from less than 2% to more than
10% strain. 相似文献
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Ralph Lunkwitz 《Liquid crystals》1999,26(1):131-134
Some new calamitic chiral mesogens (2,5-diphenyl-1,3,4-thiadiazoles, 2,5-diphenylpyrimidines and a biphenylyl benzoate) incorporating the 1-alkylpropynyl moiety have been synthesized as enantiomerically enriched materials (ee c. 87%) and/or as racemates. Their liquid crystalline properties were studied by polarizing microscopy, differential scanning calorimetry and electro-optical investigation. Thereby it was found that most of the new compounds exhibit smectic C phases. The spontaneous polarization (Ps) of the optically active materials was measured to be around 10 nCcm-2. 相似文献
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Ralph W. Wilkerson 《代数通讯》2013,41(2):121-134
Generalized function theory on finite dimensional linear associative algebras over the fieldo freals has pro- duced many forms o f generalized regular1ty Of particularin - terest are the forms o fregularity known as S-regularity and F- regularity. It is well known that functions regular in one sense need not be regular in the other. Here we prove a transformation theorem which allows the formation o f F-regular functions from S- regular functions. Furthermore, a classi flcation theorem is proved that determines the algebras for which this transformation property holds. 相似文献
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