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101.
This note deals with three-dimensional models for rate-independent processes describing materials undergoing phase transformations with heat transfer. The problem is formulated within the framework of generalized standard solids by the coupling of the momentum equilibrium equation and the flow rule with the heat transfer equation. The existence of a global solution for this thermodynamically consistent problem is obtained by using a fixed-point argument combined with global energy estimates. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
102.
Bruckert L Herrmann M Lorenzi C 《The Journal of the Acoustical Society of America》2006,119(6):3542-3545
The present study shows that on average, exposure to a 15 min, 5 kHz tone modulated sinusoidally in amplitude at 16 Hz with a 100% depth does not affect significantly amplitude modulation (AM) detection thresholds measured between 4 and 64 Hz when listeners are extensively trained to the AM detection task, with and without adaptor before data collection. These results are compatible with previous work given that a clear 6-dB adaptation effect was observed during the first pilot trials. However, the results reveal that adaptation effects are not robust, and suggest that the mechanisms underlying adaptation to AM must be reevaluated. 相似文献
103.
Saleta Vazquez‐Rodriguez Miranda Wright Catherine M. Rogers Adam P. Cribbs Srikannathasan Velupillai Martin Philpott Henry Lee James E. Dunford Kilian V. M. Huber Matthew B. Robers James D. Vasta Marie‐Laetitia Thezenas Sarah Bonham Benedikt Kessler James Bennett Oleg Fedorov Florence Raynaud Adam Donovan Julian Blagg Vassilios Bavetsias Udo Oppermann Chas Bountra Akane Kawamura Paul E. Brennan 《Angewandte Chemie (International ed. in English)》2019,58(2):515-519
104.
Lyskawa J Le Derf F Levillain E Mazari M Sallé M Dubois L Viel P Bureau C Palacin S 《Journal of the American Chemical Society》2004,126(39):12194-12195
A tetrathiafulvalene-based redox-switchable ligand with unprecedented electrochemical recognition properties for a metallic cation is described and is chemically immobilized onto a solid surface. The recognition properties for Pb2+ are maintained at the solid-liquid interface. Evidence of the modulation of the binding affinity of the modified surface, as a function of the potential applied, is given by EQCM analyses and by direct measurements of residual Pb2+ concentration in solution by atomic absorption. 相似文献
105.
We consider a composite material constituted of carbon or glass fibres included in a resin which becomes solid when it is heated up (reaction of reticulation). The mathematical modelling of the cure process is given by a kinetic equation describing the evolution of the reaction of reticulation coupled with the heat equation. The geometry of the composite material is periodic, with a small period . First we prove the existence and uniqueness of a solution by using Schauder's fixed point theorem. Then, by using an asymptotic expansion, we derive the homogenized problem which describes the macroscopic behaviour of the material. We prove the convergence of the solution of the problem to the solution of the homogenized problem when ? tends to zero and we obtain an error estimate in a case of weak non-linearity. Finally we solve numerically the homogenized problem. To cite this article: S. Meliani et al., C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
106.
M. Garçon D. Legrand R.M. Lombard B. Mayer M. Rouger Y. Terrien A. Nakach 《Nuclear Physics A》1985,445(4):669-684
Using an internal jet target in the Saturne synchrotron, we have measured the proton-proton differential elastic cross section at 90° c.m. as a continuous function of energy (from 500 to 1200 MeV) during the acceleration of the beam. The energy resolution is about 2 MeV. The results are compared to predictions of phase-shift analyses and discussed in connection with amplitude analyses at 90° c.m. No resonant structure was observed and no evidence for narrow dibaryons was found. 相似文献
107.
Laetitia Raynal Nicholas C. Rose Dr. James R. Donald Dr. Christopher D. Spicer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):69-88
Photochemical reactions have been the subject of renewed interest over the last two decades, leading to the development of many new, diverse and powerful chemical transformations. More recently, these developments have been expanded to enable the photochemical macrocyclisation of peptides and small proteins. These constructs benefit from increased stability, structural rigidity and biological potency over their linear counterparts, providing opportunities for improved therapeutic agents. In this review, an overview of both the established and emerging methods for photochemical peptide macrocyclisation is presented, highlighting both the limitations and opportunities for further innovation in the field. 相似文献
108.
Julien Henri Laetitia Minder Kevin Mohanasundaram Sbastien Dilly Anne Goupil-Lamy Carmelo Di Primo Anny Slama Schwok 《Molecules (Basel, Switzerland)》2022,27(22)
This work identifies new ligands of the nucleoprotein N of SARS-CoV-2 by in silico screening, which used a new model of N, built from an Alphafold model refined by molecular dynamic simulations. The ligands were neuropeptides, such as substance P (1-7) and enkephalin, bound at a large site of the C-terminal or associated with the N-terminal β−sheet. The BA4 and BA5 Omicron variants of N also exhibited a large site as in wt N, and an increased flexibility of the BA5 variant, enabling substance P binding. The binding sites of some ligands deduced from modeling in wt N were assessed by mutation studies in surface plasmon resonance experiments. Dynamic light scattering showed that the ligands impeded RNA binding to N, which likely inhibited replication. We suggest that the physiological role of these neuropeptides in neurotransmission, pain and vasodilation for cholecystokinin and substance P could be altered by binding to N. We speculate that N may link between viral replication and multiple pathways leading to long COVID-19 symptoms. Therefore, N may constitute a “danger hub” that needs to be inhibited, even at high cost for the host. Antivirals targeted to N may therefore reduce the risk of brain fog and stroke, and improve patients’ health. 相似文献
109.
Dr. Matthieu Autillo Laetitia Guerin Dr. Thomas Dumas Dr. Mikhail S. Grigoriev Dr. Alexandre M. Fedoseev Sebastiano Cammelli Pier Lorenzo Solari Dr. Dominique Guillaumont Dr. Philippe Guilbaud Dr. Philippe Moisy Dr. Hélène Bolvin Dr. Claude Berthon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(17):4435-4451
The magnetic properties of LnIII and AnIII complexes formed with dipicolinate ligands have been studied by NMR spectroscopy. To know precisely the geometries of these complexes, a crystallographic study by single-crystal X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) in solution was performed. Several methods to separate the paramagnetic shifts observed in the NMR spectra were applied to these complexes. Methods using a number of nuclei of the dipicolinate ligands revealed an abrupt change in the geometries of the complexes and a metal–ligand interaction in the middle of the lanthanide series. A study of the variation of the paramagnetic shifts with temperature demonstrated that higher-order terms of the dipolar and contact contributions are required, especially for the lightest LnIII and almost all the studied AnIII. Bleaney's parameters <Sz>a and relating to the contact and dipolar terms, respectively, were deduced from experimental data and compared with the results of ab initio calculations. Quite a good agreement was found for the temperature dependencies of <Sz>a and . However, the values obtained from cation magnetic anisotropy calculations showed some discrepancies with the values derived from Bleaney's equation defined for LnIII. Other parameters, such as the crystal field parameter and the hyperfine constants Fi obtained from the experimental data of the [An(ethyl-dpa)3]3− complexes (ethyl-dpa=4-ethyl-2,6-dipicolinic acid), are at odds with the assumptions underlying Bleaney's theory. 相似文献
110.
New 3,5-disubstituted 1,2,4-oxadiazoles were synthesized in five steps by ionic liquid-phase organic synthesis (IoLiPOS) methodology. The strategy involved the preparation of amidoxime from the ionic liquid-phase bound arylnitrile. Addition of various carboxylic acid to the amidoxime produced the expected 3,5-disubstituted 1,2,4-oxadiazoles via the stable O-acyl amidoxime intermediate grafted on the ionic liquid-phase. The 1,2,4-oxadiazoles were easily cleaved by transesterification under mild reaction conditions in high purity with good overall yields. The structures of the intermediates in each step were verified by routine spectroscopic analysis (1H, 13C NMR, and HRMS). 相似文献