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121.
Matthias Golecki Jochen Lach Alexander Jeremies Frank Lungwitz Dr. Michael Fronk Prof. Dr. Georgeta Salvan Prof. Dr. Dietrich R. T. Zahn Jaena Park Dr. Yulia Krupskaya Dr. Vladislav Kataev Prof. Dr. Rüdiger Klingeler Prof. Dr. Bernd Büchner Benjamin Mahns Prof. Dr. Martin Knupfer Dr. Pablo F. Siles Dr. Daniel Grimm Prof. Dr. Oliver G. Schmidt Andreas Reis Prof. Dr. Werner R. Thiel Daniel Breite Prof. Dr. Bernd Abel Prof. Dr. Berthold Kersting 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(24):7787-7801
A new strategy for the fixation of redox‐active dinickel(II) complexes with high‐spin ground states to gold surfaces was developed. The dinickel(II) complex [Ni2L(Cl)]ClO4 ( 1 ClO4), in which L2? represents a 24‐membered macrocyclic hexaaza‐dithiophenolate ligand, reacts with ambidentate 4‐(diphenylphosphino)benzoate (dppba) to form the carboxylato‐bridged complex [Ni2L(dppba)]+, which can be isolated as an air‐stable perchlorate [Ni2L(dppba)]ClO4 ( 2 ClO4) or tetraphenylborate [Ni2L(dppba)]BPh4 ( 2 BPh4) salt. The auration of 2 ClO4 was probed on a molecular level, by reaction with AuCl, which leads to the monoaurated NiII2AuI complex [NiII2L(dppba)AuICl]ClO4 ( 3 ClO4). Metathesis of 3 ClO4 with NaBPh4 produces [NiII2L(dppba)AuIPh]BPh4 ( 4 BPh4), in which the Cl? is replaced by a Ph? group. The complexes were fully characterized by ESI mass spectrometry, IR and UV/Vis spectroscopy, X‐ray crystallography ( 2 BPh4 and 4 BPh4), cyclic voltammetry, SQUID magnetometry and HF‐ESR spectroscopy. Temperature‐dependent magnetic susceptibility measurements reveal a ferromagnetic coupling J=+15.9 and +17.9 cm?1 between the two NiII ions in 2 ClO4 and 4 BPh4 (H=?2 JS1S2). HF‐ESR measurements yield a negative axial magnetic anisotropy (D<0), which implies a bistable (easy axis) magnetic ground state. The binding of the [Ni2L(dppba)]ClO4 complex to gold was ascertained by four complementary surface analytical methods: contact angle measurements, atomic‐force microscopy, X‐ray photoelectron spectroscopy, and spectroscopic ellipsometry. The results indicate that the complexes are attached to the Au surface through coordinative Au? P bonds in a monolayer. 相似文献
122.
Sebastian Haupt René Schnorr Maria Poetsch Alexander Mansel Marcel Handke Berthold Kersting 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(2):779-786
The Sr2+ extraction properties of some 25,27-bis(carbonylmethoxy)calix[4]arenes, in which ester (–CH2CO2Et), keto (–CH2COCH3) and acid functionalities (–CH2CO2H) have been attached to the lower rim, are reported. Strontium ion extraction experiments were performed in a chloroform/water system, and the extraction performance analyzed by radiotracing using the short-lived radio nuclide 85Sr. Effects of pH value, ligand to metal ratio, temperature, extraction time and strontium species on the extraction behavior were examined. It was observed that the 25,27-bis(carboxymethoxy)calix[4]arene derivatives are potent extracting agents towards the strontium ion, showing remarkable extraction performance in competition with a series of organic and inorganic impurities and in a synthetic groundwater. The crystal structure of 25,27-bis(acetonyloxy)calix[4]arene is also reported. 相似文献
123.
Simon Steinhauer Dr. Julia Bader Dr. Hans‐Georg Stammler Dr. Nikolai Ignat‘ev Prof. Dr. Berthold Hoge 《Angewandte Chemie (International ed. in English)》2014,53(20):5206-5209
The synthesis and complete characterization of functional, highly Lewis acidic tris(pentafluoroethyl)silanes as well as tetrakis(perfluoroalkyl)silanes Si(C2F5)4 and Si(C2F5)3CF3 by direct fluorination is described. The reaction of SiCl4 with LiC2F5 invariably affords (pentafluoroethyl)fluorosilicates. To avoid silicate formation by fluoride transfer from LiC2F5 the Lewis acidity of the silane has to be decreased by electron‐donating substituents, such as dialkylamino groups. The easily accessible Si(C2F5)3NEt2 is a valuable precursor for a series of tris(pentafluoroethyl)silanes. 相似文献
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Wavelength stabilized 980 nm uncooled pump laser modules for erbium-doped fiber amplifiers 总被引:2,自引:0,他引:2
Tomas Pliska Sebastian Arlt Rainer Bttig Tim Kellner Isabella Jung Nicolai Matuschek Pascal Mauron Bernd Mayer Stefan Mohrdiek Jürgen Müller Susanne Pawlik Hans-Ulrich Pfeiffer Berthold Schmidt Boris Sverdlov Stefan Teodoropol Jrg Troger Bernd Valk Christoph Harder 《Optics and Lasers in Engineering》2005,43(3-5):271
We review the development of wavelength stabilized 980 nm pump laser modules without active temperature stabilization for applications in erbium-doped fiber amplifiers. Operation over a wide temperature range with an output power exceeding 400 mW at an ambient temperature of 70°C is demonstrated. The overall reliability of uncooled modules is estimated to be well below 500 FIT at all operating conditions. Such devices are made possible by continuous development and steady improvement of the pump laser chip, the optimization of the fiber Bragg grating stabilization scheme, careful design of the module package, and extended reliability analysis on the basis of stress tests as well as field data. 相似文献
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Berthold J.E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1990,78(3):486-511
The functions necessary in broadband communications systems at speeds above 50 Mb/s are discussed. The types of components and functionality that are needed for access to networks and for the transmission and routing of traffic within networks are identified. Integrated circuit components used for customer-network access, network multiplexing, and switching are reviewed. It is shown that currently available digital VLSI technology is capable of achieving both the speeds and the levels of integration necessary to allow broadband network access even to residential subscribers 相似文献