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101.
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Abstract The knowledge of water exchange reaction mechanism in aqueous solutions of Gd3+ polyaminocarboxylates is important for the understanding of the relatively slow water exchange rates measured for these complexes. Variable ressure measurements show a change of mechanism from associatively activated on [Gd(H2O)8]3+ and [Gd(PDTA)(H2O2)2]? to probably limiting dissociative on the MRI contrast agents [Gd(DOTA)(H2O)]?, [Gd(DTPA)(H2O)]2? and [Gd(DTPA-BMA)(H2O)]. 相似文献
103.
Lionel Cucala Christophe Demattei Paulo Lopes Andre Ribeiro 《Computational Statistics》2013,28(1):357-369
We propose a new spatial scan statistic based on graph theory as a method for detecting irregularly-shaped clusters of events over space. A graph-based method is proposed for identifying potential clusters in spatial point processes. It relies on linking the events closest than a given distance and thus defining a graph associated to the point process. The set of possible clusters is then restricted to windows including the connected components of the graph. The concentration in each of these possible clusters is measured through classical concentration indices based on likelihood ratio and also through a new concentration index which does not depend on any alternative hypothesis. These graph-based spatial scan tests seem to be very powerful against any arbitrarily-shaped cluster alternative, whatever the dimension of the data. These results have applications in various fields, such as the epidemiological study of rare diseases or the analysis of astrophysical data. 相似文献
104.
For the Ore extension R[t, S,D], where R is a prime ring, we describe prime having zero intersection with R. 相似文献
105.
Kristina O. Kvashnina Anna Yu. Romanchuk Ivan Pidchenko Lucia Amidani Evgeny Gerber Alexander Trigub Andre Rossberg Stephan Weiss Karin Popa Olaf Walter Roberto Caciuffo Andreas C. Scheinost Sergei M. Butorin Stepan N. Kalmykov 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):18044-18044
106.
Huebl H Hoehne F Grolik B Stegner AR Stutzmann M Brandt MS 《Physical review letters》2008,100(17):177602
The electrical detection of spin echoes via echo tomography is used to observe coherent processes associated with the electrical readout of the spin state of phosphorus donor electrons in silicon near a SiO2 interface. Using the Carr-Purcell pulse sequence, an echo decay with a time constant of 1.7+/-0.2 micros is observed and discussed in terms of decoherence and recombination times. Electrical spin echo tomography thus can be used to study the dynamics of the spin-dependent transport processes, e.g., in realistic spin qubit devices for quantum information processing. 相似文献
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Humberto Andre Potes-Lesoinne Fernando Ramirez-Alvarez Victor H. Perez-Gonzalez Sergio O. Martinez-Chapa Roberto Carlos Gallo-Villanueva 《Electrophoresis》2022,43(1-2):249-262
The survival of living beings, including humanity, depends on a continuous supply of clean water. However, due to the development of industry, agriculture, and population growth, an increasing number of wastewaters is discarded, and the negative effects of such actions are clear. The first step in solving this situation is the collection and monitoring of pollutants in water bodies to subsequently facilitate their treatment. Nonetheless, traditional sensing techniques are typically laboratory-based, leading to potential diminishment in analysis quality. In this paper, the most recent developments in micro- and nano-electrochemical devices for pollutant detection in wastewater are reviewed. The devices reviewed are based on a variety of electrodes and the sensing of three different categories of pollutants: nutrients and phenolic compounds, heavy metals, and organic matter. From these electrodes, Cu, Co, and Bi showed promise as versatile materials to detect a grand variety of contaminants. Also, the most commonly used material is glassy carbon, present in the detection of all reviewed analytes. 相似文献
110.
Corrigendum: Reactions with a Metalloid Tin Cluster {Sn10[Si(SiMe3)3]4}2−: Ligand Elimination versus Coordination Chemistry 下载免费PDF全文