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941.
Paramagnetic DOSY: An Accurate Tool for the Analysis of the Supramolecular Interactions between Lanthanide Complexes and Proteins
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Sandrine Denis‐Quanquin Dr. François Riobé Dr. Marc‐André Delsuc Dr. Olivier Maury Dr. Nicolas Giraud 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):18123-18131
Diffusion ordered NMR is implemented to determine accurately the mobility of paramagnetic tris‐dipicolinate lanthanide complexes that are versatile probes of protein structure. It is shown that diffusion coefficient ratios can be measured with an accuracy of 1 % using a standard BPPLED pulse sequence, which allows for observing significant, though weak, variations when different species are interacting with the paramagnetic compound. We demonstrate that this approach is complementary to classical chemical shift titration experiments, and that it can be applied successfully to probe the supramolecular dynamic interactions between lanthanide complexes and small molecules on the one hand, or to determine rapidly their affinity for a targeted protein. 相似文献
942.
Kuan Fang Ren Grard Gouesbet Grad Ghan Denis Lebrun Cafer
zkul Alain Kleitz 《Particle & Particle Systems Characterization》1996,13(2):156-164
Imaging techniques in particle sizing have always been important. Nevertheless, owing to the progress in CCD cameras, these techniques have found new potential which strongly depends on the capability to describe the image formation. Based on a combination of the generalized Lorenz-Mie theory and the diffraction theory, the image characteristics are described, taking into account the beam size, particle location, direction of observation and collecting optics characteristics. In the case of forward detection, a finite coherence is introduced and the results are compared with those obtained by a convolution approach, with the point spread function assumed to be Gaussian. Then some experimental results are displayed which underline the improvement achieved in particle size measurement. 相似文献
943.
944.
Largely different product distributions were observed on the action of various carboxylic esters with 1,4-di(bromomagnesio)butane and its homologue 1,5-di(bromomagnesio)pentane. The much larger yields of reduction product with the latter are the evidence for the structural geometric requirements for the annelation step. 相似文献
945.
946.
Christine Letrou Denis Crété Jean-Claude Pernot Abdelali Rabhi Pierre Encrenaz 《International Journal of Infrared and Millimeter Waves》1987,8(4):333-353
Tests of niobium-nitride-based SIS junctions in our experimental receiver at ENS1 have shown the remarkable stability in time and through thermal cycling of these high TC material junctions; they were used to evaluate the real junction temperature in our vacuum cryogenerator. Results of heterodyne mixing experiments are presented at 100 GHz, showing that further progress in fabrication would be necessary. Detection experiments were performed at 460 GHz with encouraging results. 相似文献
947.
948.
949.
Denis N. Buckley Elizabeth Harvey Sung-Nee G. Chu 《Monatshefte für Chemie / Chemical Monthly》2002,20(1):785-798
Film formation on compound semiconductors under anodic conditions is discussed. The surface properties of InP electrodes were examined following anodization in an (NH4)2S electrolyte. The observation of a current peak in the cyclic voltammetric curve was attributed to selective etching of the substrate and a film formation process. AFM images of samples anodized in the sulfide solution revealed surface pitting. Thicker films formed at higher potentials exhibited extensive cracking as observed by optical and electron microscopy, and this was explicitly demonstrated to occur ex situ rather than during the electrochemical treatment. The composition of the thick film was identified as In2S3 by EDX and XPS. The measured film thickness varies linearly with the charge passed, and comparison between experimental thickness measurements and theoretical estimates for the thickness indicate a porosity of over 70%. Cracking is attributed to shrinkage during drying of the highly porous film and does not necessarily imply stress in the wet film as grown. During the growth of the thick porous film, spontaneous current oscillations have been observed. The frequency of oscillation was found to be proportional to the current density, regardless of whether the measurements were carried out during a potential sweep or at constant potential. Thus, the charge passed per oscillation remained constant. A characteristic value of approximately 0.3 C · cm−2 was measured under potential sweep conditions, and a similar value was obtained at constant potential. 相似文献
950.
Laurent Denis 《Commentarii Mathematici Helvetici》1995,70(1):235-247
Résumé Dans [P1] P. Philippon a démontré un lemme de multiplicités sur un groupe algébrique en employant des méthodes d'algèbre commutative.
On introduit ici la théorie de l'intersection pour enlever une constante 2 qui appara?ssait dans le résultat final de [P1]. 相似文献