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排序方式: 共有1335条查询结果,搜索用时 15 毫秒
31.
Laura Cussonneau Ccile Coudy-Gandilhon Christiane Deval Ghita Chaouki Mehdi Djelloul-Mazouz Yoann Delorme Julien Hermet Guillemette Gauquelin-Koch Ccile Polge Daniel Taillandier Julien Averous Alain Bruhat Cline Jousse Isabelle Papet Fabrice Bertile Etienne Lefai Pierre Fafournoux Anne-Catherine Maurin Lydie Combaret 《International journal of molecular sciences》2023,24(1)
32.
Surya V. Prabhakar Vattikuti Jie Zeng Rajavaram Ramaraghavulu Jaesool Shim Alain Mauger Christian M. Julien 《International journal of molecular sciences》2023,24(1)
Bismuth-based nanostructures (BBNs) have attracted extensive research attention due to their tremendous development in the fields of photocatalysis and electro-catalysis. BBNs are considered potential photocatalysts because of their easily tuned electronic properties by changing their chemical composition, surface morphology, crystal structure, and band energies. However, their photocatalytic performance is not satisfactory yet, which limits their use in practical applications. To date, the charge carrier behavior of surface-engineered bismuth-based nanostructured photocatalysts has been under study to harness abundant solar energy for pollutant degradation and water splitting. Therefore, in this review, photocatalytic concepts and surface engineering for improving charge transport and the separation of available photocatalysts are first introduced. Afterward, the different strategies mainly implemented for the improvement of the photocatalytic activity are considered, including different synthetic approaches, the engineering of nanostructures, the influence of phase structure, and the active species produced from heterojunctions. Photocatalytic enhancement via the surface plasmon resonance effect is also examined and the photocatalytic performance of the bismuth-based photocatalytic mechanism is elucidated and discussed in detail, considering the different semiconductor junctions. Based on recent reports, current challenges and future directions for designing and developing bismuth-based nanostructured photocatalysts for enhanced photoactivity and stability are summarized. 相似文献
33.
Znini Mohamed Cristofari Gregory Majidi Lhou El Harrak Abdelhay Paolini Julien Costa Jean 《Food science and biotechnology》2013,22(1):113-119
Essential oil of aerial parts of Warionia saharae was obtained by hydrodistillation and analyzed by GC and GC-MS. Thirty-nine compounds were identified, accounting for 93.2% of the total oil. β-Eudesmol (34.9%), nerolidol-E (23%), and linalool (15.2%) were the most abundant components. The antifungal activity of the W. saharae oil was tested by poisoned food (PF) technique and the volatile activity (VA) assay against 3 phytopathogenic causing the deterioration for apple. The results indicated that the W. saharae oil inhibited significantly the mycelial growth of all strains tested (p<0.05). The minimum inhibitory concentration against Alternaria sp. was 2 μL/mL air in VA assay, whereas >2 μL/mL in PF technique for all strains. Fungal spore production was completely inhibited at 1 μL/mL air for Alternaria sp. and at 2 μL/mL air for Penicillium expansum and Rhizopus stolonifer. 相似文献
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A new method is developed to obtain guaranteed error bounds on pointwise quantities of interest for linear transient viscodynamics
problems. The calculation of strict error bounds is based on the concept of “constitutive relation error” (CRE) and the solution
of an adjoint problem. The central and original point of this work is the treatment of the singularity in space and time introduced
by the loading of the adjoint problem. Hence, the adjoint solution is decomposed into two parts: (i) an analytical part determined
from Green’s functions; (ii) a residual part approximated with classical numerical tools (finite element method, Newmark integration
scheme). The capabilities and the limits of the proposed approach are analyzed on a 2D example. 相似文献
37.
Pierre Melchior Mathieu Pellet Julien Petit Jean-Marie Cabelguen Alain Oustaloup 《Signal, Image and Video Processing》2012,6(3):421-428
Muscle models are useful in bio-inspired robotic, because they allow to reproduce accurately natural motion. When they are used for robotic issue, they need to be compact and embeddable. The non-integer model order has the advantage to ensure a parametrical parsimony that permits to implant it easily on an embedded system. Thus, a fractional multi-model of muscle was identified and presented in later paper. This model is able to predict the response of a motor unit to an electrical stimulation, considering isometric contractions (that is to say, muscle length is constant). There are three different physiological types of motor unit (FR, FF, and S). The aim of this work is to study muscle length impact on the multi-model and the limitations of the linear multi-model. Previous paper was published using FR type motor unit. In this paper, the results of the study using S type motor unit are presented. 相似文献
38.
A comparison of partially acetylated nanocellulose,nanocrystalline cellulose,and nanoclay as fillers for high‐performance polylactide nanocomposites 下载免费PDF全文
Jon Trifol David Plackett Cecile Sillard Ole Hassager Anders Egede Daugaard Julien Bras Peter Szabo 《应用聚合物科学杂志》2016,133(14)
Partially acetylated cellulose nanofibers (CNF) were chemically extracted from sisal fibers and the performance of those CNF as nanofillers for polylactide (PLA) for food packaging applications was evaluated. Three PLA nanocomposites; PLA/CNF (cellulose nanofibers), PLA/CNC (nanocrystalline cellulose), and PLA/C30B (CloisiteTM 30B, an organically modified montmorillonite clay) were prepared and their properties were evaluated. It was found that CNF reinforced composites showed a larger decrease on oxygen transmission rate (OTR) than the clay‐based composites; (PLA/CNF 1% nanocomposite showed a 63% of reduction at 23°C and 50% RH while PLA/C30B 1% showed a 26% decrease) and similar behavior on terms of water vapor barrier properties with 46 and 43%, respectively of decrease on water vapor transmission rate at 23°C and 50% RH (relative humidity). In terms of mechanical and thermomechanical properties, CNF‐based nanocomposites showed better performance than clay‐based composites without affecting significantly the optical transparency. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43257. 相似文献
39.
Nanocomposites of PBAT and cellulose nanocrystals modified by in situ polymerization and melt extrusion 总被引:1,自引:0,他引:1 下载免费PDF全文
Carolina L. Morelli Mohamed N. Belgacem Márcia C. Branciforti Marie C. B. Salon Julien Bras Rosario E. S. Bretas 《Polymer Engineering and Science》2016,56(12):1339-1348
Cellulose nanocrystals (CNC) were successfully grafted with a low molecular weight poly(butylene glutarate) through an in situ polymerization procedure. The grafting treatment decreased the CNC hydrophilic character and increased the onset of their thermal degradation by approximately 20°C, thus increasing the possibilities of CNC application. Composites of grafted and nongrafted CNC with a poly(butylene‐adipate‐co‐terephthalate) (PBAT) matrix were prepared by melt extrusion. The CNC addition led to an increase of 50% of the tensile elastic modulus of the PBAT. In addition, dynamic mechanical thermal analysis showed that the composite with CNC retained its high modulus even at temperatures far above the glass transition temperature of PBAT. At 60°C the storage modulus of the composite with CNC was approximately 200% higher than that of the pure PBAT. Thus, in this work, nanocomposites of improved properties were obtained through a combination of in situ polymerization and melt extrusion. POLYM. ENG. SCI., 56:1339–1348, 2016. © 2016 Society of Plastics Engineers 相似文献
40.
Rami Khazaka Etienne Moulin Mathieu Boccard Loïc Garcia Simon Hnni Franz‐Josef Haug Fanny Meillaud Christophe Ballif 《Progress in Photovoltaics: Research and Applications》2015,23(9):1182-1189
We compare the performance of two back reflector designs on the optoelectrical properties of microcrystalline silicon solar cells. The first one consists of a 5‐µm‐thick low‐pressure chemical vapor deposition (LPCVD)‐ZnO electrode combined with a white sheet; the second one incorporates an Ag reflector deposited on a thin LPCVD‐ZnO layer (with thickness below 200 nm). For this latter design, the optical loss in the nano‐rough Ag reflector can be strongly reduced by smoothing the surface of the thin underlying ZnO layer, by means of an Ar‐plasma treatment. Because of its superior lateral conductivity, the thin‐ZnO/Ag back reflector design provides a higher fill factor than the dielectric back reflector design. When decreasing the roughness of the front electrode with respect to our standard front LPCVD‐ZnO layer, the electrical cell performance is improved; in addition, the implementation of the thin‐ZnO/Ag back reflector leads to a significant relative gain in light trapping. Applying this newly optimized combination of front and back electrodes, the conversion efficiency is improved from 8.9% up to 9.4%, for cells with an active‐layer thickness of only 1.1 µm. We thereby highlight the necessity to optimize simultaneously the front and back electrodes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献