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1.
Massoumi Sina Challamel Noël Lerbet Jean Wautier Antoine Nicot François Darve Félix 《Meccanica》2022,57(8):2043-2066
Meccanica - This study is an attempt towards a better understanding of the length scale effects on the bending response of the granular beams. To this aim, a unidimensional discrete granular chain... 相似文献
2.
Laguel Yassine Pillutla Krishna Malick Jérôme Harchaoui Zaid 《Set-Valued and Variational Analysis》2021,29(4):967-996
Set-Valued and Variational Analysis - R. Tyrell Rockafellar and his collaborators introduced, in a series of works, new regression modeling methods based on the notion of superquantile (or... 相似文献
3.
Dr. Samuel Oger Damien Schapman Dr. Romain Mougeot Dr. Stéphane Leleu Dr. Noëlle Lascoux Dr. Patrice Baldeck Dr. Magalie Bénard Dr. Thibault Gallavardin Dr. Ludovic Galas Dr. Xavier Franck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(46):10954-10964
Epicocconone 1 is a natural chromophore isolated from the fungus Epicoccum nigrum that has shown applications in proteomics and fluorescent microscopy thanks to its unique pro-fluorescence properties. The modification of the skeleton of the natural product by replacing the triene side chain by a fluorenyl scaffold can noticeably increase the fluorophore's absorption coefficient. The synthesis of the analogues of the natural product has been made possible by the use of a palladium-catalyzed carbonylation reaction, allowing the construction of the β-keto-dioxinone key intermediate. Two-photon absorption cross-section measurements of the fluorenyl epicocconone analogues show a structure dependency with values ranging from 60 to 280 GM and live cell imaging show intense staining of intracellular vesicle-like structures around the nucleus. 相似文献
4.
Mouna Smida Jérome Lhôste Mohamed Dammak Santiago Garcia-Granda 《Arabian Journal of Chemistry》2019,12(8):2519-2523
Crystal structure of Fe2F5(H2O)(Htaz)(taz)(Hdma) which crystallizes in the triclinic system space group with unit cell parameters a = 8.8392(5) Å, b = 9.1948(5) Å, c = 9.5877(5) Å, α = 82.070(3)°, β = 63.699(3)°, γ = 89.202(3)°, Z = 2, and V = 690.91(7) Å3, was synthesized under hydrothermal conditions at 393 K for 72 h, by a mixture of FeF2/FeF3, 1,2,4-triazole molecule (Htaz), and hydrofluoric acid solution (HF 4%) in dimethylformamide solvent (DMF). The main feature of this material is the coexistence of two oxidation states for iron atoms (Fe2+, Fe3+) in the unit cell, which associate by opposite fluorine corners of FeF5N and FeF2N4 octahedra, and/or triazole molecule which originates the 2D produces material. The structure determination, performed from single crystal X-ray diffraction data, lead to the R1/WR2 reliability factors 0.031/0.087. Thermal stability studies (TG/DTG/DTA) show that the decomposition provides in the temperature range 473–773 K and no mass loss was detected before 473 K. Mass spectrometry (MS) has been used. The optical absorption of the solid was measured at the corresponding λmax using UV–vis diffuse-reflectance spectrum. 相似文献
5.
Romain Bénéteau Anne Boussonnière Jean‐Christophe Rouaud Prof. Dr. Jacques Lebreton Dr. Jérôme Graton Prof. Dr. Denis Jacquemin Dr. Muriel Sebban Prof. Dr. Hassan Oulyadi Ghanem Hamdoun Dr. Amber N. Hancock Prof. Dr. Carl H. Schiesser Dr. Fabrice Dénès 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4809-4824
α‐Bromo aluminium acetals are suitable substrates for Ueno–Stork‐like radical cyclisations affording γ‐lactols and acid‐sensitive methylene‐γ‐lactols in high yields. The mechanistic study herein sets the scope and limitation of this reaction. The influence of the halide (or chalcogenide) atom X (X=Cl, Br, I, SPh, SePh) in the precursors α‐haloesters, as well as influence of the solvent and temperature was studied. The structure of the aluminium acetal intermediates resulting from the reduction of the corresponding α‐haloesters has been investigated by low‐temperature 13C‐INEPT diffusion‐ordered NMR spectroscopy (DOSY) experiments and quantum calculations, providing new insights into the structures of these thermally labile intermediates. Oxygen‐bridged dimeric structures with a planar Al2O2 ring are proposed for the least hindered aluminium acetals, while monomeric structures seem to prevail for the most hindered species. A comparison against the radical cyclisation of aluminium acetals derived from allyl and propargyl alcohols with the parent Ueno–Stork has been made at the BHandHLYP/6‐311++G(d,p) level of theory, highlighting mechanistic similarities and differences. 相似文献
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Theodore Flack Thibaut Constantin Sylvain Penasse Dr. Jérôme Dejeu Béatrice Gennaro Dr. Muriel Jourdan Aurélien Laguerre Marc Pirrotta Dr. David Monchaud Dr. Nicolas Spinelli Prof. Eric Defrancq 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(5):1760-1767
A water‐soluble template‐assembled synthetic G‐quartet (TASQ) based on the use of a macrocyclodecapeptide scaffold was designed to display stable intramolecular folds alone in solution. The preformation of the guanine quartet, demonstrated by NMR and CD investigations, results in enhanced peroxidase‐type biocatalytic activities and improved quadruplex‐interacting properties. Comparison of its DNAzyme‐boosting properties with the ones of previously published TASQ revealed that, nowadays, it is the best DNAzyme‐boosting agent. 相似文献
9.
Experimental Design in Nonlinear Case Applied to Hydrocracking Model: How Many Points Do We Need and Which Ones? 下载免费PDF全文
In this work, different experimental design techniques were applied to a hydrocracking conversion model (single response). The selection of points was carried out using Federov's algorithm from an experimental database containing 48 points. The sequential design methodology was also applied. Results show that the D‐optimality criterion can provide valuable information for determination of the minimum number of experiments required to achieve acceptable precision. It is shown that only 22 points are enough to estimate parameters instead of the original database of 48 points. If sequential techniques are used, only 13 points are needed. This work provides useful theoretical and practical guidelines for experimental design in single‐response problems. 相似文献
10.
Set-Valued and Variational Analysis - Nonsmoothness is often a curse for optimization; but it is sometimes a blessing, in particular for applications in machine learning. In this paper, we present... 相似文献