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121.
122.
Evidence is presented for the first time that ‘naked’ Fe+ ions, complexed to the NH2 group of primary amines, are capable of intramolecularly activating C? C bonds in a highly specific mode without preceding C? H activation. 相似文献
123.
Dipl.-Phys. Sigurd Hofmann Dr. H. K. Walter Dr. A. Weitsch 《Zeitschrift für Physik A Hadrons and Nuclei》1970,230(1):37-64
γ-γ-angular correlation measurements with Ge(Li) detectors and NaJ(Tl) detectors provided theE2/M1 mixing ratios of the following gamma transitions: 3 1 + →2 2 + (475.3 keV), 2 2 + →2 1 + (563.3 keV), 4 2 + →4 1 + (569.4 keV), 3 1 + →2 1 + (1,039 keV). The angular correlation measurements were only consistent with spin 3 of the 1,643 keV level. The half life of the 1,401 keV level was determined by delayed coincidence techniques to beT 1/2 (1,401 keV)≦30 ps. 相似文献
124.
Dr. Sigurd Elliger 《Mathematische Zeitschrift》1970,118(3):215-218
Ohne Zusammenfassung 相似文献
125.
During isochronal anneal sequences the number of Hg, Tl and Bi atoms implanted into Ge has been found to decrease. This decrease occurs for all three species and has been observed for samples implanted at room temperature as well as for hot implants (300—350°C). The decrease starts at anneal temperatures of 350—550°C. Similar results have been obtained for In and Sb implanted Ge. For samples implanted with Hg to doses leading to amorphous layers, the decrease in the number of implanted atoms seems to be related to the reordering of the amorphous layer. The experiments show that no diffusion of the implanted atoms into the bulk material occurs and the decrease observed is attributed to be a diffusion of the atoms to the surface followed by outdiffusion, thermal etching or both. 相似文献
126.
Derya Baran Felix M. Pasker Stephan Le Blanc Gregor Schnakenburg Tayebeh Ameri Sigurd Höger Christoph J. Brabec 《Journal of polymer science. Part A, Polymer chemistry》2013,51(4):987-992
A new donor‐acceptor copolymer consisting of triazoloquinoxaline and 9,9‐dialkylfluorene units on the main chain has been synthesized, characterized and evaluated as donor material in bulk heterojunction solar cells using PC61BM as an acceptor. The resulting polymer PTQF showed good thermal stability and solubility in common organic solvents. Cyclic Voltammetry measurements showed that the PTQF has HOMO–LUMO energy levels of ?5.13 and ?3.62 eV, respectively. DFT calculations revealed that the HOMO is delocalized all over the thiophene and fluorene units and the LUMO is localized mainly on the triazole and pyrazine units. PTQF absorbs broadly in the visible region and exhibits a bandgap of 1.4 eV. Photovoltaic devices exhibited 1.7% efficiency for 1:2 PTQF:PC61BM blend ratio using Ca/Ag electrodes. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
127.
Cold‐gas traps enable the trapping of cold as well as heavy gases and aerosols in strong stationary ultrasonic fields. The effect can be explained by standard acoustic principles and it can be used to adjust temperatures down to –100 °C in the pressure nodes of a stationary ultrasonic field. In this investigation the cold‐gas traps have been generated by using a very powerful acoustic levitator. The cold‐gas traps have been improved, e.g., to study the formation and growth of ice and snow flakes from primary ice aerosol as well as freezing and melting processes of single and contact‐less levitated water drops. High‐speed monitoring (VIS, IR) of the first‐stage freezing process of levitated water droplets is reported. 相似文献
128.
129.
Discotic liquid crystals with an inverted structure 总被引:1,自引:0,他引:1
130.
[reaction: see text] Two large extraannular-functionalized phenyl-ethynyl macrocycles containing m-terphenyl units are described. The synthesis of the m-terphenyl building blocks is based on the transformation of pyrylium salts to arenes. 相似文献