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711.
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Daniel E. Diaz David A. Quist Austin E. Herzog Andrew W. Schaefer Ioannis Kipouros Mayukh Bhadra Edward I. Solomon Kenneth D. Karlin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):17736-17740
The dioxygen reactivity of a series of TMPA‐based copper(I) complexes (TMPA=tris(2‐pyridylmethyl)amine), with and without secondary‐coordination‐sphere hydrogen‐bonding moieties, was studied at ?135 °C in 2‐methyltetrahydrofuran (MeTHF). Kinetic stabilization of the H‐bonded [( TMPA)CuII(O2.?)]+ cupric superoxide species was achieved, and they were characterized by resonance Raman (rR) spectroscopy. The structures and physical properties of [( TMPA)CuII(N3?)]+ azido analogues were compared, and the O2.? reactivity of ligand–CuI complexes when an H‐bonding moiety is replaced by a methyl group was contrasted. A drastic enhancement in the reactivity of the cupric superoxide towards phenolic substrates as well as oxidation of substrates possessing moderate C?H bond‐dissociation energies is observed, correlating with the number and strength of the H‐bonding groups. 相似文献
713.
By analogy with the conventional (q=1) case, a squeezed vacuum state for theq-bosonic oscillator is constructed. It can be shown that this obeys quantum noise relations similar to those found in the undeformed state. Using the unitary displacement operator for theq-boson algebra, we show that it is possible to construct aq-squeezed state which is parameterised by elements of a noncommutative algebra. These states satisfy the Robertson-Schrödinger Uncertainty Relation and can be generalised toq-analogues of correlated coherent states.Presented at the 4th Colloquium Quantum Groups and Integrable Systems, Prague, 22–24 June 1995.One of the authors (RJM) would like to thank the organizers of this colloquium for giving him the opportunity to attend this meeting. He would also like to thank the Carnegie Trust for support in travelling expenses. 相似文献
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Zeev Zalevsky David Mendlovic M. Alper Kutay Haldun M. Ozaktas Jonathan Solomon 《Optics Communications》2001,190(1-6):95-101
In this communication we propose performing two-dimensional correlation operation between phase-space representations based on the fractional Fourier transform, instead of correlating the signals themselves. A numerical examples clearly indicates superior discrimination performance. 相似文献
719.
J.K. Thomas H. Padma Kumar Annamma John V. Suni K. Joy S. Solomon J. Koshy 《Journal of Physics and Chemistry of Solids》2009,70(3-4):703-706
Nanocrystals of GdBa2HfO5.5 perovskite ceramic materials, of the family A2(BB′)O6, were synthesized using an auto-igniting combustion of a precursor solution containing metal ions, oxidant and a fuel. Phase purity and particulate properties of the as-prepared powder were examined using X-ray diffraction, differential thermal and thermogravimetric analyses, Fourier-transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopic techniques. These nanocrystals were sintered to high density (~98% of the theoretical density) at ~1620 °C for 2 h.The sintering behavior, dielectric constant and dielectric loss factor of the samples showed variations in magnitude with that of the samples prepared by conventional solid-state route. 相似文献
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