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排序方式: 共有394条查询结果,搜索用时 15 毫秒
91.
Dr. Matthieu Fonvielle Dr. Inés Li de La Sierra‐Gallay Dr. Afaf H. El‐Sagheer Maxime Lecerf Delphine Patin Dr. Dénia Mellal Dr. Claudine Mayer Dr. Didier Blanot Dr. Nittaya Gale Dr. Tom Brown Dr. Herman van Tilbeurgh Dr. Mélanie Ethève‐Quelquejeu Dr. Michel Arthur 《Angewandte Chemie (International ed. in English)》2013,52(28):7278-7281
92.
An adaptive (Lagrangian) boundary element approach is proposed for the general three‐dimensional simulation of confined free‐surface Stokes flow. The method is stable as it includes remeshing capabilities of the deforming free surface and thus can handle large deformations. A simple algorithm is developed for mesh refinement of the deforming free‐surface mesh. Smooth transition between large and small elements is achieved without significant degradation of the aspect ratio of the elements in the mesh. Several flow problems are presented to illustrate the utility of the approach, particularly as encountered in polymer processing and rheology. These problems illustrate the transient nature of the flow during the processes of extrusion and thermoforming, the elongation of a fluid sample in an extensional rheometer, and the coating of a sphere. Surface tension effects are also explored. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
93.
A facile access to a wide range of original saturated N-heterocyclic ureas is described using, as a key step, a Michael-type reaction involving isocyanates or amines on a piperidine framework possessing an α,β-unsaturated ester functionality. 相似文献
94.
Pd/Cu-catalyzed one-pot reaction of 1-trimethylsilyl-2-arylalkynes with propargylic chlorides in the presence of TBAF is described. The present new procedure is applicable to a wide range of silylated arylalkynes with both electron-withdrawing and electron-donating substituents. Functionalized allenynes can thus be obtained in good yields without prior deprotection of the alkynes. 相似文献
95.
We report in this paper the use of Co2Si silicide as a template layer for the integration of magnetic materials and structures on silicon substrate. By undertaking Co deposition on silicon at a temperature of about 300 °C, we show that it is possible to obtain a smooth and epitaxial Co2Si layer, which can act as a template layer preventing the reaction between Co and other transition metals with silicon. Two examples of over-growth of magnetic materials and structures on this template layer will be presented: growth of ferromagnetic Co layers and of magnetic tunnel junctions (Co(Fe)/AlOx/NiFe). 相似文献
96.
Jonathan Derrien François Tondeur Christopher Berrendorf Isabelle Gerardy 《X射线光谱测定》2020,49(1):243-250
The MICOS Compton spectrometer is a tool for the routine spectrometric control of X-ray generators, mainly in the medical field (<150 kV). The use of a pen-type NaI (Tl) detector with thin Be window allows to extend its range down to 6 keV, for a better evaluation of the low-E side of the spectrum, which is determined by filtration. A specific problem is encountered in the deconvolution of the spectrum at very low energies, dominated by the K escape of iodine. The proposed solution combines an approximate step-by-step application of the GRAVEL algorithm, whereas the MAXED unfolding software is used for reaching the final solution. A new computer code was developed that combines spectrum acquisition and deconvolution and calculates the main characteristics of the source spectrum: end point energy, mean energy, energy at 50% of the left slope, and air kerma at 1 m from the source. 相似文献
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Modulation of Relaxivity,Suspension Stability,and Biodistribution of Dendronized Iron Oxide Nanoparticles as a Function of the Organic Shell Design 下载免费PDF全文
Aurélie Walter Audrey Parat Antonio Garofalo Sophie Laurent Luce Vander Elst Robert N. Muller Tao Wu Emilie Heuillard Eric Robinet Florent Meyer Delphine Felder‐Flesch Sylvie Begin‐Colin 《Particle & Particle Systems Characterization》2015,32(5):552-560
Nanoparticles (NPs) with a mean diameter of 10 nm are functionalized with three dendrons: D1 a PEGylated PAMAM dendron of generation 0.5, D2 a hydrophilic oligoethyleneglycol‐derivatized dendron (D2) displaying a phosphonic acid at the focal point, and D2–2P the same dendron than D2 but with two phosphonic acid anchoring agents. Their grafting is confirmed by IR spectroscopy and elemental analysis. All dendronized NPs are stable over a long period of time in suspensions in water and in different physiological media and display a mean hydrodynamic diameter smaller than 50 nm whatever the molecule architecture. NMRD profiles and relaxivity measurements highlight the influence of the molecule architecture on the water diffusion close to the magnetic core thus influencing the relaxation properties at low magnetic field. The high hydrophilic architecture of the dendron D2 by contrast to dendron D1 allows maintaining the colloidal stability in different conditions while ensuring a very good accessibility of water molecule close to the magnetic core. Coupling of a fluorescent dye on dendrons have allowed investigating the biodistribution of dendronized NPs, which are found to be quickly eliminated through urinary and hepatobiliary pathways within 4 h. Furthermore, no enhanced permeation and retention effect in tumors can be observed. 相似文献