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71.
Dieter Riemer 《Datenschutz und Datensicherheit - DuD》2018,42(12):772-776
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Dieter Heymann 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(6):1079-1086
Abstract A search was made for C60 fullerene by High Performance Liquid Chromatography in char formed on a Norway Spruce struck by lightning. Firm proof that C60 occurs in the char was not obtained. However, the evidence showed the possible presence of 1 ppb C60. 相似文献
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An undercooled melt possesses an enhanced free enthalpy that opens up the possibility to crystallize metastable crystalline solids in competition with their stable counterparts. Crystal nucleation selects the crystallographic phase whereas the growth dynamics controls microstructure evolution. We apply containerless processing techniques such as electromagnetic and electrostatic levitation to containerlesss undercool and solidify metallic melts. Owing to the complete avoidance of heterogeneous nucleation on container-walls a large undercooling range becomes accessible with the extra benefit that the freely suspended drop is direct accessible for in situ observation of crystallization far away from equilibrium. Results of investigations of maximum undercoolability on pure zirconium are presented showing the limit of maximum undercoolability set by the onset of homogeneous nucleation. Rapid dendrite growth is measured as a function of undercooling by a high-speed camera and analysed within extended theories of non-equilibrium solidification. In such both supersaturated solid solutions and disordered superlattice structure of intermetallics are formed at high growth velocities. A sharp interface theory of dendrite growth is capable to describe the non-equilibrium solidification phenomena during rapid crystallization of deeply undercooled melts. Eventually, anomalous growth behaviour of Al-rich Al–Ni alloys is presented, which may be caused by forced convection. 相似文献
76.
Xinghua Yu Jeremy L. Caron S. S. Babu John C. Lippold Dieter Isheim David N. Seidman 《Metallurgical and Materials Transactions A》2011,42(12):3669-3679
BlastAlloy 160 (BA160) is a low-carbon martensitic steel strengthened by copper and M2C precipitates. Heat-affected zone (HAZ) microstructure evaluation of BA160 exhibited softening in samples subjected to the
coarse-grained HAZ thermal simulations of this steel. This softening is partially attributed to dissolution of copper precipitates
and metal carbides. After subjecting these coarse-grained HAZs to a second weld thermal cycle below the A
c1 temperature (at which austenite begins to form on heating), recovery of strength was observed. Atom-probe tomography and
microhardness analyses correlated this strength recovery to re-precipitation of copper precipitates and metal carbides. A
continuum model is proposed to rationalize strengthening and softening in the HAZ regions of BlastAlloy 160. 相似文献
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Highly Crystalline Films of PCPDTBT with Branched Side Chains by Solvent Vapor Crystallization: Influence on Opto‐Electronic Properties 下载免费PDF全文
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Dr. Robert Kuhnert Dr. Lydia Kuhnert Dr. Menyhárt-B. Sárosi Sven George Dr. Dijana Draca Dr. Svetlana Paskas Dr. Bettina Hofmann Prof. Dr. Dieter Steinhilber Prof. Dr. Walther Honscha Prof. Dr. Sanja Mijatović Prof. Dr. Danijela Maksimović-Ivanić Prof. Dr. Evamarie Hey-Hawkins 《ChemMedChem》2022,17(1):e202100588
12-Lipoxygenase is crucial for tumour angiogenesis. 5,6,7-Trihydroxy-2-phenyl-4H-1-benzopyran-4-one (baicalein) is a suitable inhibitor for this enzyme but is rapidly metabolised in vivo. Thus, an improvement of the metabolic stability is necessary to enhance the therapeutic efficiency. An emerging approach to enhance metabolic stability of carbon-based pharmaceuticals is the use of metabolically stable, non-toxic boron clusters, such as dicarba-closo-dodecaborane(12)s (carboranes) as phenyl mimetics. Therefore, the unsubstituted phenyl ring of baicalein was replaced by meta-carborane, resulting in borcalein, the carborane analogue of baicalein. This substitution resulted in a decreased inhibitory activity toward 12-lipoxygenase, but led to increased toxicity in melanoma (A375, B16, B16F10) and colon cancer cell lines (SW480, HCT116, CT26CL25) with decreased tumour selectivity in comparison to baicalein. Surprisingly, borcalein displays a different mechanism of cytotoxicity with increased intracellular production of reactive oxygen species (ROS), reactive nitrogen species (RNS) and nitric oxide (NO). 相似文献
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