The Experts below are selected from a list of 18 Experts worldwide ranked by ideXlab platform
Francisco Zaera - One of the best experts on this subject based on the ideXlab platform.
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1 1 naphthyl ethylamine adsorption on platinum surfaces on the mechanism of chiral modification in catalysis
Journal of the American Chemical Society, 2008Co-Authors: Ilkeun Lee, Shinji Kaneko, Francisco ZaeraAbstract:The adsorption of 1-(1-naphthyl)ethylamine (NEA) on platinum surfaces has been characterized by reflection-absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) both under ultrahigh vacuum and in situ from liquid solutions. The main focus of this study was to identify the mechanism by which single enantiomers of NEA bestow chirality on the platinum surface. Evidence was acquired for both of the prevailing explanations available in the literature for the NEA behavior: formation of supramolecular chiral templates and complexation of individual modifiers with the reactant. Indeed, TPD titrations of NEA-modified Pt(111) using propylene oxide (PO) as a chiral Probe Point to a relative enhancement in the adsorption of one enantiomer over the other at intermediate NEA coverages, which is the behavior expected from the templating mechanism. However, a difference in adsorption energetics was also observed. Both the TPD and RAIRS data suggest possible interactions between the adsorbed NEA and adjacent PO that differ according to the relative chirality of the two compounds. The NEA uptake from solution displays additional enantioselectivity, in particular when the adsorption of enantiopure compounds is compared with that of racemic mixtures, and also Points to possible adsorption changes induced by ethyl pyruvate, a common reactant in chiral hydrogenation processes.
Masaaki Emori - One of the best experts on this subject based on the ideXlab platform.
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Measuring method of three thermophysical parameters of solids by a thermal Probe with instantaneous Point contact: Measuring principle
Heat Transfer—Asian Research, 2003Co-Authors: Ichiro Takahashi, Masaaki EmoriAbstract:A new method for instantaneous measurement of three thermophysical parameters of solids in situ is proposed. The measurement principle is based on a transient heat conduction model of a thermal Probe Point contacting a testing body. The measurement of temperature response has been made using the Probe of a sheathed K-type thermocouple in this experiment. Ratios of both thermal conductivity and thermal effusivity between the Probe and the testing body are determined from curve-fitting with the theoretical response to the measured one. As a result, it is shown that the measurement is reproducible and the accuracies of measured thermophysical parameters are good enough to apply this method to many kinds of solids. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(3): 191–201, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10084
Ilkeun Lee - One of the best experts on this subject based on the ideXlab platform.
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1 1 naphthyl ethylamine adsorption on platinum surfaces on the mechanism of chiral modification in catalysis
Journal of the American Chemical Society, 2008Co-Authors: Ilkeun Lee, Shinji Kaneko, Francisco ZaeraAbstract:The adsorption of 1-(1-naphthyl)ethylamine (NEA) on platinum surfaces has been characterized by reflection-absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) both under ultrahigh vacuum and in situ from liquid solutions. The main focus of this study was to identify the mechanism by which single enantiomers of NEA bestow chirality on the platinum surface. Evidence was acquired for both of the prevailing explanations available in the literature for the NEA behavior: formation of supramolecular chiral templates and complexation of individual modifiers with the reactant. Indeed, TPD titrations of NEA-modified Pt(111) using propylene oxide (PO) as a chiral Probe Point to a relative enhancement in the adsorption of one enantiomer over the other at intermediate NEA coverages, which is the behavior expected from the templating mechanism. However, a difference in adsorption energetics was also observed. Both the TPD and RAIRS data suggest possible interactions between the adsorbed NEA and adjacent PO that differ according to the relative chirality of the two compounds. The NEA uptake from solution displays additional enantioselectivity, in particular when the adsorption of enantiopure compounds is compared with that of racemic mixtures, and also Points to possible adsorption changes induced by ethyl pyruvate, a common reactant in chiral hydrogenation processes.
E Miranda - One of the best experts on this subject based on the ideXlab platform.
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failure analysis of mim and mis structures using Point to event distance and angular probability distributions
IEEE Transactions on Device and Materials Reliability, 2014Co-Authors: Xavier Saura Mas, Scott Monaghan, Paul K Hurley, Jordi Sune, E MirandaAbstract:Multiple breakdown (BD) spots are generated in large $(>\hbox{10}^{-4}\ \hbox{cm}^{2})$ circular and square area metal–insulator–metal and metal–insulator–semiconductor devices using ramped and constant-voltage electrical stresses. Due to the important local thermal effects that take place at the very moment of the formation of the conductive paths spanning the insulating layer, the failure events become visible on the top metal electrode of the structures as a Point pattern. The resulting Point-to-event distance and angular histograms are compared with the theoretical distributions corresponding to a complete spatial randomness $(CSR)$ process. The location of the voltage Probe tip over the top electrode is considered here as the singular Point from which the positions of the BD spots are referred to. In this way, we are able to assess the influence of the Probe Point on the final BD spot distribution. In most of the cases, this distribution is consistent with $CSR$ , but after prolonged electrical stress, a deviation is detected. This departure from $CSR$ is ascribed to the concentration of the current lines in the top electrode toward the center of the structure. The methods reported here are general and can be used for analyzing the generation of similar Point patterns occurring in other structures or material systems.
Shinji Kaneko - One of the best experts on this subject based on the ideXlab platform.
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1 1 naphthyl ethylamine adsorption on platinum surfaces on the mechanism of chiral modification in catalysis
Journal of the American Chemical Society, 2008Co-Authors: Ilkeun Lee, Shinji Kaneko, Francisco ZaeraAbstract:The adsorption of 1-(1-naphthyl)ethylamine (NEA) on platinum surfaces has been characterized by reflection-absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) both under ultrahigh vacuum and in situ from liquid solutions. The main focus of this study was to identify the mechanism by which single enantiomers of NEA bestow chirality on the platinum surface. Evidence was acquired for both of the prevailing explanations available in the literature for the NEA behavior: formation of supramolecular chiral templates and complexation of individual modifiers with the reactant. Indeed, TPD titrations of NEA-modified Pt(111) using propylene oxide (PO) as a chiral Probe Point to a relative enhancement in the adsorption of one enantiomer over the other at intermediate NEA coverages, which is the behavior expected from the templating mechanism. However, a difference in adsorption energetics was also observed. Both the TPD and RAIRS data suggest possible interactions between the adsorbed NEA and adjacent PO that differ according to the relative chirality of the two compounds. The NEA uptake from solution displays additional enantioselectivity, in particular when the adsorption of enantiopure compounds is compared with that of racemic mixtures, and also Points to possible adsorption changes induced by ethyl pyruvate, a common reactant in chiral hydrogenation processes.