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101.
A Ru(terpy)(phen) motif has been inscribed in a 39-membered ring by functionalizing the ligands and subsequently performing a cyclization reaction on the complex; by visible light irradiation, a dramatic geometrical changeover of the cyclic complex takes place which can be reversed thermally. 相似文献
102.
A novel type of interferometer was designed and tested experimentally. It combines the advantages of the spatial path separation used in the two-wave polarized Jamin interferometer and the high sensitivity that characterizes the multiwave Fabry-Perot interferometer. Furthermore, when it is sandwiched between crossed polarizers it shows a sensitivity to intracavity anisotropies that is proportional to the square of the Fabry-Perot interferometer's finesse. 相似文献
103.
Acetylenes are hydrated in benzene-acetonitrile mixtures in the presence of phosphoric acid saturated with boron trifluoride and in the absence of heavy metal ions to the corresponding ketones in high yields. 相似文献
104.
105.
Solid solutions of hydrogen in thulium are investigated, mainly by X-ray determinations in the temperature range 20–500°C. Several observations lead us to distinguish between two variaties α and α1. In the range of existence of the α1 phase, below the transition temperature of 120°C, the hydrogen interstitials induce in the metal lattice a behaviour different from that of the α phase, as concerns the phase equilibrium, the additional resistivity, and the lattice anisotropy.Several simple models are proposed for the explanation of this anomaly, encountered also in other heavy rate earth-hydrogen systems. 相似文献
106.
Anne‐Sophie Bonnet‐Bendhia Axel Tillequin 《Mathematical Methods in the Applied Sciences》2001,24(14):1089-1111
A generalized mode matching method that applies to a wide class of scattering problems is developed in the time harmonic two‐dimensional Helmholtz case. This method leads by variational means to an integro‐differential formulation whose unknown is the trace of the field on an unbounded one‐dimensional interface. The well‐posedness is proved after a careful study of the rather original functional framework. Owing to a fundamental density result—based upon some properties of a singular integral operator similar to the Hilbert transform—the limiting absorption principle related to this original formulation is established. Finally, two other situations are emphasized. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
107.
An experimental study of the turbulent kinetic energy balance is performed in a LEBU manipulated turbulent boundary layer. The estimation of almost all the terms of the k-equation is obtained by hot wire anemometry. Near the manipulating device, strong alterations are observed, when compared with the natural conditions. The wake of the manipulator imposes two distinct zones. The lower part is characterized by negligible production compensated by diffusion, while, in the outer part, a large excess of production is balanced by diffusion and dissipation. The excess of dissipation rapidly vanishes downstream. The relaxation process is slower for production and diffusion.A version of this paper was presented at the 11th Symposium on Turbulence, University of Missouri-Rolla, Oct. 17–19, 1988 相似文献
108.
Nanozeolite‐LTL with GdIII Deposited in the Large and EuIII in the Small Cavities as a Magnetic Resonance Optical Imaging Probe 下载免费PDF全文
Florian Mayer Wuyuan Zhang Thomas Brichart Prof. Olivier Tillement Dr. Célia S. Bonnet Dr. Éva Tóth Dr. Joop A. Peters Dr. Kristina Djanashvili 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(12):3358-3364
The immense structural diversity of more than 200 known zeolites is the basis for the wide variety of applications of these fascinating materials ranging from catalysis and molecular filtration to agricultural uses. Despite this versatility, the potential of zeolites in medical imaging has not yet been much exploited. In this work a novel strategy is presented to selectively deposit different ions into distinct framework locations of zeolite‐LTL (Linde type L) and it is demonstrated that the carefully ion‐exchanged Gd/Eu‐containing nanocrystals acquire exceptional magnetic properties in combination with enhanced luminescence. This smart exploitation of the framework structure yields the highest relaxivity density (13.7 s?1 L g?1 at 60 MHz and 25 °C) reported so far for alumosilicates, rendering these materials promising candidates for the design of dual magnetic resonance/optical imaging probes, as demonstrated in preliminary phantom studies. 相似文献
109.
Sophie Laine Jean-Franois Morfin Mathieu Galibert Vincent Aucagne Clia S. Bonnet va Tth 《Molecules (Basel, Switzerland)》2021,26(8)
Two DO3A-type ligands conjugated to substrates of urokinase (L3) and caspase-3 (L4) via a propyl-amide linker were synthesized and their lanthanide(III) (Ln3+) complexes studied. A model compound without peptide substrate (L2) and an amine derivative ligand mimicking the state after enzymatic cleavage (L1) were also prepared. Proton Nuclear Magnetic Relaxation Dispersion (NMRD) profiles recorded on the gadolinium(III) (Gd3+) complexes, complemented with the assessment of hydration numbers via luminescence lifetime measurements on the Eu3+ analogues, allowed us to characterize the lanthanide coordination sphere in the chelates. These data suggest that the potential donor groups of the peptide side chains (carboxylate, amine) interfere in metal coordination, leading to non-hydrated LnL3 and LnL4 complexes. Nevertheless, GdL3 and GdL4 retain a relatively high relaxivity due to an important second-sphere contribution generated by the strongly hydrophilic peptide chain. Weak PARACEST effects are detected for the amine-derivative EuL1 and NdL1 chelates. Unfortunately, the GdL3 and GdL4 complexes are not significantly converted by the enzymes. The lack of enzymatic recognition of these complexes can likely be explained by the participation of donor groups from the peptide side chain in metal coordination. 相似文献
110.