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排序方式: 共有3476条查询结果,搜索用时 15 毫秒
151.
Pierre Miquel Yas Yamin Karine Lombaert Christophe Dujardin Pascal Granger 《Topics in Catalysis》2009,52(13-20):1791-1798
The influence of the support synthesis for the preparation of supported Pd/LaFeO3 perovskite based catalysts and the nature of the palladium precursor on the catalytic performances in the selective reduction of NO to N2 by hydrocarbons have been investigated. According to the preparation method, subsequent surface and bulk characterisation revealed significant changes in the degree of dispersion and the chemical environment of oxidic palladium species depending on the extent of interaction with the support. Pd nitrate precursor leads to the stabilisation of the Pd surface concentration. The metal support interactions thus obtained strongly enhance the catalytic performances, particularly the resistance to thermal ageing whereas sol–gel synthesis produces the higher support activity. 相似文献
152.
The module of elasticity is one of the most important mechanical properties defining the strength of a material which is a prerequisite to design a component from its early stage of conception to its field of application. When a material is to be thermally sprayed, mechanical properties of the deposited layers differ from the bulk material, mainly due to the anisotropy of the highly textured coating microstructure. The mechanical response of the deposited layers significantly influences the overall performance of the coated component. It is, therefore, of importance to evaluate the effective module of elasticity of the coating. Conventional experimental methods such as microindentation, nanoindentation and four-point bending tests have been investigated and their results vary significantly, mainly due to inhomogeneous characteristics of the coating microstructure. Synchrotron radiation coupled with a tensile test rig has been proposed as an alternative method to determine the coating anisotropic elastic behavior dependence on crystallographic orientations. The investigation was performed on Inconel 718 (IN718) HVOF coatings sprayed on IN718 substrates. Combining these experimental techniques yield a deeper understanding of the nature of the HVOF coating Young’s modulus and thus a tool for Design Practice for repair applications. 相似文献
153.
Floriane Pailleux Pauline Maes Michel Jaquinod Justine Barthelon Marion Darnaud Claire Lacoste Yves Vandenbrouck Benoît Gilquin Mathilde Louwagie Anne-Marie Hesse Alexandra Kraut Jrme Garin Vincent Leroy Jean-Pierre Zarski Christophe Bruley Yohann Cout Didier Samuel Philippe Ichai Jamila Faivre Virginie Brun 《International journal of molecular sciences》2021,22(20)
Acute liver injury (ALI) is a severe disorder resulting from excessive hepatocyte cell death, and frequently caused by acetaminophen intoxication. Clinical management of ALI progression is hampered by the dearth of blood biomarkers available. In this study, a bioinformatics workflow was developed to screen omics databases and identify potential biomarkers for hepatocyte cell death. Then, discovery proteomics was harnessed to select from among these candidates those that were specifically detected in the blood of acetaminophen-induced ALI patients. Among these candidates, the isoenzyme alcohol dehydrogenase 1B (ADH1B) was massively leaked into the blood. To evaluate ADH1B, we developed a targeted proteomics assay and quantified ADH1B in serum samples collected at different times from 17 patients admitted for acetaminophen-induced ALI. Serum ADH1B concentrations increased markedly during the acute phase of the disease, and dropped to undetectable levels during recovery. In contrast to alanine aminotransferase activity, the rapid drop in circulating ADH1B concentrations was followed by an improvement in the international normalized ratio (INR) within 10–48 h, and was associated with favorable outcomes. In conclusion, the combination of omics data exploration and proteomics revealed ADH1B as a new blood biomarker candidate that could be useful for the monitoring of acetaminophen-induced ALI. 相似文献
154.
Nicolas Bulidon Valérie Deydier Frederic Bumbieler Claude Duret-Thual Christophe Mendibide Didier Crusset 《工业材料与腐蚀》2021,72(1-2):154-165
Since 2014, the concept developed for the disposal of high-level radioactive waste in the French deep geological repository project Cigéo includes a cement-based grout material. This cement-based grout material will be injected between the casing and the claystone to neutralize the potential acidity resulting from the claystone oxidation induced by the drilling process of the disposal cell. In these conditions of pH (around 10.5) and temperature (90°C, maximum expected during the disposal), the metallic materials could be sensitive to stress corrosion cracking (SCC). In this project, different environments (aerated or deaerated, at room temperature or at 90°C) and synthetic solutions are considered to reproduce the different periods expected during the long life repository. The project is based on electrochemical measurements (polarization curves to define the SCC critical domain of potentials), slow strain rate tensile tests, and long-term immersion for crack initiation and propagation tests. 相似文献
155.
Christophe Laurent Geoffroy Chevallier Alicia Weibel Alain Peigney Claude Estournès 《Carbon》2008,46(13):1812-1816
Bulk samples of double-walled carbon nanotubes are prepared for the first time. The best spark plasma sintering conditions are (1100 °C, 100 MPa). Raman spectroscopy and scanning electron microscopy show that the nanotubes are undamaged. The density is equal to 1.29 g cm−3 and the pores are all below 6 nm in diameter. The electrical conductivity is equal to 1650 S cm−1. The transverse fracture strength is equal to 47 MPa. 相似文献
156.
Sang-Wook Park In-Joe Sohn Dong-Soo Suh Hidehiro Kumazawa 《Korean Journal of Chemical Engineering》1999,16(5):549-555
The absorption of CO2 from a mixture of CO2/N2 gas was carried out using a flat-stirred vessel and the polytetrafluoroethylene hollow fiber contained aqueous 2-amino-2-methyl-1-propanol
(AMP) solution. The reaction of CO2 with AMP was confirmed to be a second order reversible reaction with fast-reaction region. The mass transfer resistance in
the membrane side obtained from the comparison of the measured absorption rates of CO2 in a hollow fiber contained liquid membrane with a flat-stirred vessel corresponded to about 90% of overall-mass-transfer
resistance. The mass transfer coefficient of hollow fiber phase could be evaluated, which was independent of CO2 loading. 相似文献
157.
Czarnota Christophe Koné Fousseny Haddag Badis Nouari Mohammed 《The International Journal of Advanced Manufacturing Technology》2015,80(1-4):65-90
The International Journal of Advanced Manufacturing Technology - This paper presents an hybrid numerical/analytical modeling for estimation of cutting forces in machining process. The approach... 相似文献
158.
Shabnam Sanaei Navid Mostoufi Ramin Radmanesh Rahmat Sotudeh‐Gharebagh Christophe Guy Jamal Chaouki 《加拿大化工杂志》2010,88(1):1-11
Effect of temperature on the hydrodynamics of bubbling gas–solid fluidized beds was investigated in this work. Experiments were carried out at different temperatures ranged of 25–600°C and different superficial gas velocities in the range of 0.17–0.78 m/s with sand particles. The time‐position trajectory of particles was obtained by the radioactive particle tracking technique at elevated temperature. These data were used for determination of some hydrodynamic parameters (mean velocity of upward and downward‐moving particles, jump frequency, cycle frequency, and axial/radial diffusivities) which are representative to solids mixing through the bed. It was shown that solids mixing and diffusivity of particles increases by increasing temperature up to around 300°C. However, these parameters decrease by further increasing the temperature to higher than 300°C. This could be attributed to the properties of bubble and emulsion phases. Results of this study indicated that the bubbles grow up to a maximum diameter by increasing the temperature up to 300°C, after which the bubbles become smaller. The results showed that due to the wall effect, there is no significant change in the mean velocity of downward‐moving clusters. In order to explain these trends, surface tension of emulsion between the rising bubble and the emulsion phase was introduced and evaluated in the bubbling fluidized bed. The results showed that surface tension between bubble and emulsion is increased by increasing temperature up to 300°C, however, after that it acts in oppositely. 相似文献
159.
T. E. Kim S. W. Sohn J. M. Park C. W. Bang W. T. Kim D. H. Kim 《Metals and Materials International》2013,19(4):667-671
The effect of Mn content on the evolution of microstructure and the enhancement of mechanical properties in Fe-Nb-Mn hierarchical composites consisted of ultrafine eutectic and primary dendrite has been studied by using X-ray diffractometry, scanning electron microscopy, transmission electron microcopy and compression test. Fe-11Nb-5Mn hierarchical composite consisted of α′-Fe dendrite and urtrafine α′-Fe + Fe2Nb eutectic, and exhibited a reasonably good combination of mechanical properties, i.e. yield strength of 1283 ± 10 MPa and compressive plastic strain of 7.75 ± 5%, while Fe-11Nb-15Mn composite consisted of ?-Fe dendrite and ?-Fe + Fe2Nb eutectic structure with some retained γ phase, and exhibited a far better combination of mechanical properties, i.e. higher yield strength of 1462 ± 10 MPa and larger compressive plastic strain of 11.28 ± 2%. The origin for the simultaneous enhancement of high strength and large plastic strain is attributed to ?-Fe martensite formation and strain-induced martensitic transformation from ? to α′ during deformation. 相似文献
160.
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