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We study a class of nonlinear regression models for scalar or vectorial response when the explanatory variable is a function. We introduce a consistent estimator of the parameters of models in this class when functions are evaluated at randomly chosen observation points. To cite this article: F. Rossi, B. Conan-Guez, C. R. Acad. Sci. Paris, Ser. I 340 (2005). 相似文献
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Guillerm B Darcos V Lapinte V Monge S Coudane J Robin JJ 《Chemical communications (Cambridge, England)》2012,48(23):2879-2881
Well-defined graft copolymers were obtained using a copper-catalysed azide-alkyne Huisgen's cycloaddition click reaction from both biocompatible and non-toxic poly(ε-caprolactone) and poly(2-methyl-2-oxazoline) homopolymers. Resulting amphiphilic copolymers proved to form micelles that could be used as potential drug carriers. 相似文献
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Juri Skotnitzki Alexander Kremsmair Daniel Keefer Franziska Schüppel Brieuc Le Cacher de Bonneville Regina de Vivie-Riedle Paul Knochel 《Chemical science》2020,11(20):5328
The diastereoselective SN2′-substitution of secondary alkylcopper reagents with propargylic phosphates enables the preparation of stereodefined alkylallenes. By using enantiomerically enriched alkylcopper reagents and enantioenriched propargylic phosphates as electrophiles anti-SN2′-substitutions were performend leading to α-chiral allenes in good yields with excellent regioselectivity and retention of configuration. DFT-calculations were performed to rationalize the structure of these alkylcopper reagents in various solvents, emphasizing their configurational stability in THF.The diastereoselective SN2′-substitution of secondary alkylcopper reagents with propargylic phosphates enables the preparation of stereodefined alkylallenes. 相似文献
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In recent years there has been an increasing number of applications of micro-analytical techniques, such as Secondary-Ion
Mass Spectrometry (SIMS) and Laser Ablation-ICP-MS, in the field of Earth Sciences. As a consequence, the need of well characterised
calibration standards, which are a prerequisite for these techniques, has increased considerably. Such a request is particularly
critical to SIMS due to the existence of matrix effects in the ion micro-probe analysis.
In the present work we describe a technique to prepare a reference glassy sample starting from a powdered Standard Reference
Material, represented by the basaltic rock JB-2 (Geological Survey of Japan), and report the results of EMPA and SIMS investigations
for the characterisation of the resulting glass. We put a particular emphasis on Li and B owing to their importance as geochemical
markers. We performed the in-situ analyses for the concentration of major-, minor-elements, as well as Li and B in the glassy material. The data testify that
the glass could be employed as a reference material for Li and B elemental microanalysis. It is reasonable to foresee that
the procedure proposed can be also applied to produce homogeneous glassy standards for in-situ Li and B isotope studies. 相似文献
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Brieuc Guillerm Sophie Monge Vincent Lapinte Jean‐Jacques Robin 《Journal of polymer science. Part A, Polymer chemistry》2013,51(5):1118-1128
In this contribution, we report on the self‐assembly in water of original amphiphilic poly(2‐methyl‐2‐oxazoline)‐b‐poly(tert‐butyl acrylate) copolymers, synthesized by copper‐catalyzed azide–alkyne cycloaddition (CuAAC) reaction. For such purpose, (poly(2‐methyl‐2‐oxazoline)) and (poly(tert‐butyl acrylate)) are first prepared by cationic ring‐opening polymerization and atom transfer radical polymerization, respectively. Well‐defined polymeric building blocks, ω‐N3‐P(t‐BA) and α‐alkyne‐P(MOx), bearing reactive chain end groups, are accurately characterized by matrix‐assisted laser desorption ionization time‐of‐flight spectroscopy. Then, P(MOx)n‐b‐P(t‐BA)m are achieved by polymer–polymer coupling and are fully characterized by diffusion‐ordered NMR spectroscopy and size exclusion chromatography, demonstrating the obtaining of pure amphiphilic copolymers. Consequently, the latter lead to the formation in water of well‐defined monodisperse spherical micelles (RH = 40–60 nm), which are studied by fluorescence spectroscopy, static light scattering, atomic force microscope, and transmission electronic microscopy. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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Nicola Raffone Brieuc Le Fèvre Luisa Ottolini Riccardo Vannucci Alberto Zanetti 《Mikrochimica acta》2006,155(1-2):251-255
The high sensitivity of Secondary-Ion Mass Spectrometry (SIMS) in determining very low trace-element concentrations (down
to few ppb wt) has been used to address the important issue of the Light-Lithophile Element (LLE) signatures of mantle peridotites
and their potential utility as tracers of transfer of subducted material into the overlying mantle wedge operated either by
slab-related fluids or melts. The effects of such metasomatic agents have been described and interpreted on the basis of geochemical
and isotopic characteristics of peridotites. However, direct observation of metasomatic processes occurring in the mantle
is limited because the most highly metasomatised peridotites are usually found as xenoliths which do not allow large-scale
chemical information. In this context, the Finero phlogopite-peridotite massif (Ivrea-Verbano Zone, western Italian Alps)
offers a unique opportunity because it contains hydrous mineral assemblages (amphibole + phlogopite ± apatite) and trace element
enrichments, supposed to be related to the pervasive migration of slab-derived melts. In this study we report the results
of texture-related SIMS investigations performed on a wide range of trace elements such as Li, B, Large-Ion Lithophile Elements
(LILE), Rare Earth Elements (REE), Nb, Zr, Ti on clinopyroxenes from the Finero peridotite. SIMS analyses revealed unusual
LLE signatures that highlight the role of crust-derived components and open new perspectives on the timing of metasomatic
processes. 相似文献
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Irén Simkó Christoph Schran Fabien Brieuc Csaba Fábri Oskar Asvany Stephan Schlemmer Dominik Marx Attila G. Császár 《Angewandte Chemie (International ed. in English)》2023,62(41):e202306744
Quantum mechanics dictates that nuclei must undergo some delocalization. In this work, emergence of quantum nuclear delocalization and its rovibrational fingerprints are discussed for the case of the van der Waals complex . The equilibrium structure of is planar and T-shaped, one He atom solvating the quasi-linear He−H+−He core. The dynamical structure of , in all of its bound states, is fundamentally different. As revealed by spatial distribution functions and nuclear densities, during the vibrations of the molecule the solvating He is not restricted to be in the plane defined by the instantaneously bent chomophore, but freely orbits the central proton, forming a three-dimensional torus around the chromophore. This quantum delocalization is observed for all vibrational states, the type of vibrational excitation being reflected in the topology of the nodal surfaces in the nuclear densities, showing, for example, that intramolecular bending involves excitation along the circumference of the torus. 相似文献
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