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排序方式: 共有1331条查询结果,搜索用时 15 毫秒
61.
Lauzon-Gauthier Julien Duchesne Carl Tessier Jayson 《JOM Journal of the Minerals, Metals and Materials Society》2020,72(1):287-295
JOM - A machine vision sensor was developed for predicting deviations from the optimum amount of pitch in anode formulations using paste texture analysis. It could help operators mitigate the... 相似文献
62.
Antoine Ruffini Julien Durinck Jérôme Colin Christophe Coupeau Jean Grilhé 《Acta Materialia》2013,61(12):4429-4438
Atomistic simulations based on experimental observations provide the first evidence that the interface delamination of a thin film from its substrate may start from interface steps. Buckling of the film after interface gliding from both edges of its delaminated part is also observed. In the framework of the Föppl–von Kármán theory of thin plates, the expression of the critical strain beyond which the film buckles has been then analytically determined as a function of the step height and gliding displacements. Both numerical and analytical results confirm that the formation of blisters is favoured in the neighbourhood of interfacial imperfections. 相似文献
63.
A series of LiNi1/3Mn1/3Co1/3O2 samples with α-NaFeO2 structure belonging to the D3d5 space group were synthesized using tartaric acid as a chelating agent by wet-chemical method. Different acid to metal-ion ratios R have been used to investigate the effect of this parameter on the physical and electrochemical properties. We have characterized the reaction mechanism, the structure, and morphology of the powders by TGA, XRD, SEM and TEM imaging, completed by magnetic measurements, Raman scattering spectroscopy, and complex impedance experiments. We find that the LiNi1/3Mn1/3Co1/3O2 sintered at 900 °C for 15 h with an acid to metal-ion ratio R = 2 was the optimum condition for this synthesis. For this optimized sample, only 1.3% of nickel-ions occupied the 3b Wyckoff site of the lithium-ions sublattice. The electrochemical performance has been investigated using a coin-type cell containing Li metal as the anode. The electronic performance is correlated to the concentration of the Ni(3b) defects that increase the charge transfer resistance and reduce the lithium diffusion coefficient. The optimized cell delivered an initial discharge capacity of 172 mAh g−1 in the cut-off voltage of 2.8-4.4 V, with a coulombic efficiency of 93.4%. 相似文献
64.
Franck Paganelli Giovanna Mottola Julien Fromonot Marion Marlinge Pierre Deharo Rgis Guieu Jean Ruf 《International journal of molecular sciences》2021,22(4)
The influence of hyperhomocysteinemia (HHCy) on cardiovascular disease (CVD) remains unclear. HHCy is associated with inflammation and atherosclerosis, and it is an independent risk factor for CVD, stroke and myocardial infarction. However, homocysteine (HCy)-lowering therapy does not affect the inflammatory state of CVD patients, and it has little influence on cardiovascular risk. The HCy degradation product hydrogen sulfide (H2S) is a cardioprotector. Previous research proposed a positive role of H2S in the cardiovascular system, and we discuss some recent data suggesting that HHCy worsens CVD by increasing the production of H2S, which decreases the expression of adenosine A2A receptors on the surface of immune and cardiovascular cells to cause inflammation and ischemia, respectively. 相似文献
65.
66.
Julien Orlans Carole Vincent-Monegat Isabelle Rahioui Catherine Sivignon Agata Butryn Laurent Soulre Anna Zaidman-Remy Allen M. Orville Abdelaziz Heddi Pierre Aller Pedro Da Silva 《International journal of molecular sciences》2021,22(9)
Peptidoglycan recognition proteins (PGRPs) are ubiquitous among animals and play pivotal functions in insect immunity. Non-catalytic PGRPs are involved in the activation of immune pathways by binding to the peptidoglycan (PGN), whereas amidase PGRPs are capable of cleaving the PGN into non-immunogenic compounds. Drosophila PGRP-LB belongs to the amidase PGRPs and downregulates the immune deficiency (IMD) pathway by cleaving meso-2,6-diaminopimelic (meso-DAP or DAP)-type PGN. While the recognition process is well analyzed for the non-catalytic PGRPs, little is known about the enzymatic mechanism for the amidase PGRPs, despite their essential function in immune homeostasis. Here, we analyzed the specific activity of different isoforms of Drosophila PGRP-LB towards various PGN substrates to understand their specificity and role in Drosophila immunity. We show that these isoforms have similar activity towards the different compounds. To analyze the mechanism of the amidase activity, we performed site directed mutagenesis and solved the X-ray structures of wild-type Drosophila PGRP-LB and its mutants, with one of these structures presenting a protein complexed with the tracheal cytotoxin (TCT), a muropeptide derived from the PGN. Only the Y78F mutation abolished the PGN cleavage while other mutations reduced the activity solely. Together, our findings suggest the dynamic role of the residue Y78 in the amidase mechanism by nucleophilic attack through a water molecule to the carbonyl group of the amide function destabilized by Zn2+. 相似文献
67.
Tiphaine Bazin François Rouzé-l’Alzit Alain Demourgues I. Julien C. Bertrand S. Catros Thierry Cardinal Eric Champion Manuel Gaudon 《Ceramics International》2021,47(13):18565-18574
Implants made of ceramics, and more particularly of calcium phosphates (hydroxyapatite: HA, mainly), promoting intimate contact with natural bone are nowadays merging. Addition of copper ions in bio-ceramics is expected to increase the biological compatibilities of bone graft substitutes. Previous works have shown that copper-doped hydroxyapatite (Cu-doped HA) ceramics can be prepared by solid-state sintering between HA and CuO powder mixtures at about 1100 °C; but, copper-substituted HA was found to be metastable leading to apatitic grains and Cu-rich grain boundaries during the sintering process. Ultra-rapid sintering is so needed. Selective laser sintering (SLS) is an additive manufacturing process that possesses the advantage to be based on ultra-fast sintering process under laser irradiation. SLS being used in literature for the application of laser on polymer-ceramic or poymer-metal composites the proper term all along the paper is Ceramic Powder Bed Laser Sintering (CPBLS). To achieve densification of Cu-doped HA ceramics from CPBLS process, one should control the composition/morphology/structure of the powder bed as well as three other important CPBLS parameters: (i) the applied energy from the laser beam, (ii) the laser power and the laser scanning speed, (iii) the distance between two successive lased lines. In this paper, the impact of all the main CPBLS parameters controlling the sintering of dip-coated Cu-doped HA layers on glass substrates is carefully investigated. Possibility of the creation of thin consolidated Cu-doped HA ceramic patterns, using the ultra-fast CPBLS process, is finally shown. 相似文献
68.
Julien Moriceau Patrick Houizot Theany To Abdessamad Mougari Hervé Orain Fabrice Celarié Tanguy Rouxel 《Journal of the European Ceramic Society》2021,41(1):838-848
The effect of spherulitic crystallization on the elastic moduli and fracture toughness of a barium aluminum silicate glass was investigated. The crystallization process results in Ba2Si3O8 phase and is initiated from Ba rich nuclei. Nucleation is optimal in the 690-720 °C interval. Young’s modulus is increased by 12.5% when the glass-ceramic conversion is nearly complete. Nevertheless, as the size and the volume fraction of crystals are increased, some microcracking shows up upon cooling from the crystallization temperature. An optimal improvement of the fracture toughness (SEPB method) by 27 % is observed for a 49 % volume fraction of 5 to 10 μm large spherulites. 相似文献
69.
70.
An optimized explicit low-storage fourth-order Runge–Kutta algorithm is proposed in the present work for time integration. Dispersion and dissipation of the scheme are minimized in the Fourier space over a large range of frequencies for linear operators while enforcing a wide stability range. The scheme remains of order four with nonlinear operators thanks to the low-storage algorithm. Linear and nonlinear propagation problems are finally solved to illustrate the accuracy of the present Runge–Kutta scheme. 相似文献