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Acta Mechanica Sinica 2015年第3期31卷 392-405页

作者： D.Yang Q.C.He School of Mechanical Engineering Southwest Jiaotong University Université Paris-Est Laboratoire Modélisation et Simulation Multi Echelle UMR 8208 CNRS

This work aims at determining the overall response of a two-phase elastoplastic composite to isotropic loading. The composite under investigation consists of elastic particles embedded in an elastic perfectly plastic matrix governed by the Mohr-Coulomb yield criterion and a non-associated plastic flow rule. The composite sphere assemblage model is adopted, and closed-form estimates are derived for the effective elastoplastic properties of the composite either under tensile or compressive isotropic loading. In the case when elastic particles reduce to voids, the composite in question degenerates into a porous elastoplastic material. The results obtained in the present work are of interest, in particular, for soil mechanics.

关键词： Composite Porous medium. Elastoplasticity Mohr-Coulomb yield criterion Non-associated flow rule Homogenization

Cobalt,a reactive metal in releasing hydrogen from sodium borohydride by hydrolysis:A short review and a research perspective

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Science China Chemistry 2010年第9期53卷 1870-1879页

作者： DEMIRCI Umit B AKDIM Ouardia HANNAUER Julien CHAMOUN Rita MIELE Philippe Université Lyon 1 CNRSUMR 5615Laboratoire des Multimatériaux et Interfaces

Cobalt is commonly admitted as being a promising catalyst in accelerating NaBH4 hydrolysis,being as reactive as noble metals and much more *** is the topic of the present ***,we survey(i) the NaBH4-devoted literature while especially focusing on the Co catalysts and(ii) our work on the same ***,we report(iii) reactivity results of newly developed Co-based *** both surveys,it mainly stands out that Co has been investigated as catalysts in various forms:namely,as chlorides,reduced nanoparticles(metal Co,Co boride,Co-B alloy),supported over supports and *** doing so the reactivity can be easily varied achieving H2 generation rates from few to >1000 L(H2)/min·g(metal).Nevertheless,our work can be distinguished from the NaBH4 ***,we are working on strategies that focus on making alternative Co-based *** of these strategies is illustrated here as we report new reactivity data of Co-based bimetallic supported *** example,we show that 20 wt% Co90Y10/γAl2O3-20 wt% Co95Hf5/γAl2O3 > 20 wt% Co99Zr1/γAl2O3 > 20 wt% Co/γAl2O3,the best catalysts showing HGRs of about 245 mL(H2)/min or 123 L(H2) /min·g(metals).

关键词： bimetallic catalyst cobalt heterogeneous catalysis hydrogen hydrolysis sodium borohydride sodium tetrahydroborate

Multiplexing technology for in vitro diagnosis of pathogens： the key contribution of phosphorus dendrimers

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Science China Materials 2018年第11期61卷 1454-1461页

作者： Jean Pierre Majoral Jean Marie Francois Richard Fabre Alice Senescau Serge Mignani Anne-Marie Caminade laboratoire de Chimie de Coordination du cnrs 31077 Toulouse Cedex 4France LCC-cnrs Universit6 de Toulouse CNRSToulouseFrance Dendris 31670 LabegeFrance LISBP UMR CNRS 5504 INRA 79231077 Toulouse Cedex 04France Universite Paris Descartes PRES Sorbonne Paris Cite CNRS-UMR 860Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicolgique75006 ParisFrance

After the microbiology based on Pasteur's method and polymerase chain reaction(PCR), the diagnosis company named Dendris has proposed a third-generation of diagnosis enabling the search of a broad range of pathogens with strong sensitivity and specificity. This extraordinary profile was possible thanks to the use of phosphorus dendrimers for which various techniques of deposition on a given support were investigated and described and analyzed in this report.

关键词： phosphorus dendrimers diagnosis DNA arrays multiplexing technology

Electron Backscattered Diffraction of Transgranular Crack Propagation in Soft Steel

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Chinese Physics Letters 2007年第6期24卷 1759-1762页

作者： A. Boumaiza T. Baudin N. Rouag R. Penelle laboratoire Microstructures et Defauts Universit6 Mentouri Constantine Algdrie laboratoire de Physico-Chimie de l'etat Solide UMR cnrs 8648 Paris-Sud Orsay France

We consider the crack propagation in a soft steel sheet during the formation. The drawability is considered in relation with the structural anisotropy, the mechanical behaviour is related to both the grain morphology and the texture. The structure heterogeneity could lead to the apparition of micro-cracks. The results show the texture effect on the crack propagation and on the crack arrest in soft steel during the formation. The EBSD technique allows to show that the adjustment of the grain orientation from the initial main component {111}（112） towards the deformation orientation {111}（110） incites a trans-granular crack through a grain with initial {111}（112） orientation in a globally ductile material. It is the presence of grains with {111}（110） orientation which permits the closing of micro-cracks.

关键词： INITIATION GROWTH

Petrology, Age and Geodynamic Implication of the Panafrican Granitoids Associated with the Glito-Kpatala Shear Zone (South-East Togo)

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International Journal of Geosciences 2023年第12期14卷 1193-1225页

作者： Gnanwasou Alayi Sarakawa Abalo Malibida Kpanzou Yao Agbossoumondé Essodina Padaro René-Pierre Menot Mahaman Sani Tairou Départment de Géologie Faculté des Sciences Université de Lomé Lomé Togo laboratoire magmas et volcans Université Jean Monnet Saint Etienne France

The granitic plutons associated with the Glito-Kpatala shear zone are composed of biotite and amphibole granodiorites, biotite granites, two-mica granites and aplitic granites, which are very poorly represented. The chemical and mineralogical compositions of these facies indicate that they are I type and belong to high-K calc-alkaline series, with a chemical metaluminous character displayed by the granodiorites relative to the biotite and two-mica facies whose chemical compositions vary between metaluminous and peraluminous caracter. The Th/Ta (14.04 - 43.82 ppm, mean = 26.05), Th/U (2.58 to 15.05 ppm, mean = 5.85 ppm), Zr/Hf (25.27 to 37.21, mean = 30.67 ppm) and Rb/Sr (0.16 to 4.32;mean = 1.67 ppm) ratios of these granitoids reveal a strong crustal involvement in their magmatogenesis. Variations in CaO/Na2O (0.47 - 1.44 ppm), Rb/Sr (0.14 - 0.27 ppm), Rb/Ba (0.07 - 0.14 ppm) and Sr/Y (38.21 - 174.42 ppm) ratios indicate that biotite and amphibole granodiorites with their excessive Ni (135.37 - 139.51 ppm) and Cr (395.73 - 447.74 ppm) were derived from a mafic to intermediate lower continental crust where garnet and/or amphibole were stable residual assemblage minerals. The moderate Sr/Y ratios (1.81 - 9.47 ppm) and low transition elements Ni (1 - 6.44 ppm) and Cr (7.89 - 13.47 ppm) contents in both the two-mica and biotite granites are consistent with their emplacement at relatively shallow depths in the upper to mean continental crust, at pressures below 10 Kbar. In the two-mica granites, moderate CaO/Na2O (0.20 - 0.57 ppm, mean = 0.38 ppm) and Rb/Ba (0.39 - 1.37, mean = 0.84 ppm) ratios and quite varied Rb/Sr (1.53 - 4.23 ppm, mean = 2.85 ppm) ratios indicate a predominant derivation from psammitic and pelitic metasediments rather than metagreywackes. These low ratios (0.25 ≤ CaO/Na2O ≤ 0.32, mean = 0.28 ppm;0.31 ≤ Rb/Ba ≤ 0.44, mean = 0.39 ppm;1.11 ≤ Rb/Sr ≤ 1.78, mean = 0.39 ppm) in biotite granites are more consistent with melt

关键词： Pan-African Granitoids Post-Collisional Shear Zone South-East Togo

The onset of deep recycling of supracrustal materials at the Paleo-Mesoarchean boundary

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National Science Review 2022年第3期9卷 110-118页

作者： Xiaolei Wang Ming Tang Jeff Moyen Di Wang Alfred Kr?ner Chris Hawkesworth Xiaoping Xia Hangqiang Xie Carl Anhaeusser Axel Hofmann Junyong Li Linsen Li State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University School of Earth and Space Sciences Peking University laboratoire magmas et volcans UMR6524 Université de LyonUJM-UCA-CNRS-IRD Institut für Geowissenschaften Universit?t Mainz Department of Earth Sciences University of Bristol State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Economic Geology Research Unit University of the Witwatersrand Department of Geology University of Johannesburg

The recycling of supracrustal materials, and in particular hydrated rocks, has a profound impact on mantle composition and thus on the formation of continental crust, because water modifies the physical properties of lithological systems and the mechanisms of partial melting and fractional fractionation. On the modern Earth, plate tectonics offers an efficient mechanism for mass transport from the Earth’s surface to its interior, but how far this mechanism dates back in the Earth’s history is still uncertain. Here, we use zircon oxygen(O) isotopes to track recycling of supracrustal materials into the magma sources of early Archean igneous suites from the Kaapvaal Craton, southern Africa. The mean δ18O values of zircon from TTG(tonalite–trondhjemite–granodiorite) rocks abruptly increase at the Paleo-Mesoarchean boundary(ca.3230 million years ago; Ma), from mantle zircon values of 5‰–6‰ to approaching 7.1‰, and this increase occurs in ≤3230 Ma rocks with elevated Dy/Yb ratios. The18O enrichment is a unique signature of low-temperature water–rock interaction on the Earth’s surface. Because the later phase was emplaced into the same crustal level as the older one and TTG magmas would derive from melting processes in the garnet stability field(>40 km depth), we suggest that this evident shift in TTG zircon O isotopic compositions records the onset of recycling of the mafic oceanic crust that underwent seawater hydrothermal alteration at low temperature. The onset of the enhanced recycling of supracrustal materials may also have developed elsewhere in other Archean cratons and reflects a significant change in the tectonic realm during craton formation and stabilization, which may be important processes for the operation of plate tectonics on early Earth.

关键词： zircon oxygen isotopes TTG plate tectonics deep recycling Paleo-Mesoarchean boundary

Catalytic decomposition performance for O_3 and NO_2 in humid indoor air on a MnO_x/Al_2O_3 catalyst modified by a cost-effective chemical grafting method

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Journal of Environmental Sciences 2018年第12期30卷 58-70页

作者： Longwen Chen Michel Ondarts Jonathan Outin Yves Gonthier Evelyne Gonze Université Grenoble Alpes Université Savoie Mont Blanc CNRS Laboratoire d'Optimisation de la Conception et Ingénierie de l'Environnement(LOCIE)

Processes based on non-thermal plasma（NTP） for indoor air treatment inevitably lead to the formation of toxic by-products such as ozone（O3） and nitrogen oxides（NOx）. Adding a step of heterogeneous catalysis in series with NTP could allow for the decomposition of the by-products. Therefore, different catalysts were developed based on transition metal oxides, such as NiOx, CoOxand MnOxwith different weight percentage 1, 5 and 10 wt.%,deposited on a γ-Al2O3 support. The O3 removal efficiency（ORE） and the NOxremoval efficiency（NRE） were very encouraging in dry air： about 65% and 80%, respectively, by using2 g 5 wt.% MnOx/Al2O3 catalyst under the experimental conditions. However, strongly negative effects of relative humidity（RH） on the catalytic decomposition performance were observed. To overcome this limitation, the catalyst surface was modified to make it hydrophobic using a cost-effective chemical grafting method. This treatment consisted in impregnating the 5 wt.% MnOx/Al2O3 catalyst with different trichloro（alkyl）silanes（TCAS）.The effects of different linker lengths and amounts of TCAS for the hydrophobicity and the decomposition performance of surface-modified catalysts under humid conditions were investigated. Our results show that the surface-modified catalyst with the shortest linker and 0.25 mmol/gcatof modifying agent represents the best catalytic decomposition performance for O3. Its ORE is 41% at 60% RH, which is twice that of the non-modified catalyst.

关键词： Indoor air treatment Non-thermal plasma MnOx/Al2O3catalyst Surface modification Ozone

Deciphering the role of monosaccharides during phage infection of Staphylococcus aureus

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Nano Research 2022年第10期15卷 9234-9242页

作者： Baptiste Arbez Marion Gardette Christophe Gantzer Neus Vilà Isabelle Bertrand Sofiane El-Kirat-Chatel laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement(LCPME) CNRSUniversité de Lorraine405 rue de Vandoeuvre54602 Villers-lès-NancyFrance

As phages are extensively investigated as novel therapy tools but also as transfer agents for antibiotic resistance genes,thorough understanding of phage–host interactions becomes *** for phage infection is its adhesion to the host ***,we used atomic force microscopy-based single-particle force spectroscopy with phage-decorated tips to decipher the adhesion of phage 187 on living Staphylococcus aureus *** found that addition of free N-acetyl-Dglucosamine was able to decrease phage adhesion,suggesting that this monosaccharide plays major role in phage 187 infection of ***,phage 187 adhesion on monosaccharide-coated model surfaces combined with plaque forming unit counts suggested that a direct link can be established between the propensity to bind to a saccharide and the capability of the latter to inhibit phage *** a nanoscale level,single-particle force spectroscopy was successfully used to identify a major receptor required for phage 187 infection of *** but also evidenced that this receptor was responsible for phage adhesion on *** work demonstrates that single-particle force spectroscopy is a powerful platform to screen and predict the molecular target of phages on their host surfaces.

关键词： atomic force microscopy single-particle force spectroscopy phage 187 Staphylococcus aureus phage-bacteria interactions

Evolution of the 128-cm^(-1) Raman phonon mode with temperature in Ba(Fe_(1-x)Co_x)_2As_2(x=0.065 and 0.2)

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Chinese Physics B 2015年第2期24卷 399-402页

作者：杨彦兴 Gallais Yann 方之颢石兢熊锐 School of Physics and Technology Wuhan University laboratoire Matériaux et Phénomenes Quantiques(UMR 7162 cnrs) Université Paris Diderot-Paris 7

We report electronic Raman scattering measurements on Ba（Fei1-xCox）2As2（x = 0.065 and 0.2） single crystals with Raman shifts from 9 cm^-1 up to 600 cm^-1 in the symmetry of Blg with respect to 1 Fe unit *** the crystals are cooled down,the evident quasielastic peaks of Raman spectra occur only in the crystal with x = 0.065,which is due to the contribution of orbital ordering between xz and yz Fe 3d orbitals,as we reported in another ***,we analyze the Eg phonon at 128 cm^-1,which has the same function form of its Raman tensors as those of xz and yz Fe 3d orbitals in these two crystals *** their electronic continuums,no anomalies are found in the Eg phonons of these two samples,which simply follows the expressions corresponding to the anharmonic phonon decay into acoustic phonons with the same frequencies and opposite *** results indicate that the structural and magnetic phase transition might be completely suppressed by chemical doping and there is not any indication of coupling between charge nematicity and Eg phonon mode from our experimental results,which is consistent with the results in our previous work.

关键词： Raman scattering iron-based superconductor phonon mode

Redox and acetylation coordinate ABA-independent osmotic stress response

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Molecular Plant 2022年第4期15卷 583-585页

作者： Christophe Belin Jean-Philippe Reichheld laboratoire Génome et Développement des Plantes UniversitéPerpignan Via Domitia66860 PerpignanFrance laboratoire Génome et Développement des Plantes CNRS66860 PerpignanFrance

Osmotic stress caused by drought or high salt concentrations is a major threat that limits plant development and affect crop *** the context of climate change,understanding the mechanisms by which plants perceive their environment to adapt to their development is a major question.A common feature of plants being exposed to osmotic stress is the accumulation of excessive reactive oxygen species(ROS)(Martinière et al.,2019).ROS can oxidatively damage biological molecules,such as nucleic acids,proteins,and lipids,but also play important signaling *** protect from ROS-induced oxidation,living organisms have developed a large panel of enzymatic and non-enzymatic systems to remove ROS and oxidized molecules.

关键词： functions. enzymatic coordinate