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71.
Olivier Tingaud Ghislain Montavon Alain Denoirjean Jean-François Coudert Vincent Rat Pierre Fauchais 《Journal of Thermal Spray Technology》2010,19(1-2):207-218
Suspension plasma spraying (SPS) is an alternative to conventional atmospheric plasma spraying (APS) aiming at manufacturing thinner layers (i.e., 10-100 μm) due to the specific size of the feedstock particles, from a few tens of nanometers to a few micrometers. The staking of lamellae and particles, which present a diameter ranging from 0.1 to 2.0 μm and an average thickness from 20 to 300 nm, permits to manufacture finely structured layers. Moreover, it appears as a versatile process able to manufacture different coating architectures according to the operating parameters (suspension properties, injection configuration, plasma properties, spray distance, torch scan velocity, scanning step, etc.). However, the different parameters controlling the properties of the coating, and their interdependences, are not yet fully identified. Thus, the aim of this paper is, on the one hand, to better understand the influence of operating parameters on the coating manufacturing mechanisms (in particular, the plasma gas mixture effect) and, on the other hand, to produce Al2O3-ZrO2 finely structured layers with large varieties of architectures. For this purpose, a simple theoretical model was used to describe the plasma torch operating conditions at the nozzle exit, based on experimental data (mass enthalpy, arc current intensity, thermophysical properties of plasma forming gases, etc.) and the influences of the spray parameters were determined by mean of the study of sizes and shapes of spray beads. The results enabled then to reach a better understanding of involved phenomena and their interactions on the final coating architectures permitting to manufacture several types of microstructures. 相似文献
72.
Marine Milard Fabienne Laugerette Annie Durand Charline Buisson Emmanuelle Meugnier Emmanuelle Loizon Corinne Louche‐Pelissier Valrie Sauvinet Lorna Garnier Sbastien Viel Karne Bertrand Florent Joffre David Cheillan Lydie Humbert Dominique Rainteau Pascale Plaisanci Laure B. Bindels Audrey M. Neyrinck Nathalie M. Delzenne Marie‐Caroline Michalski 《Molecular nutrition & food research》2019,63(4)
73.
Martin Alain Mune Mune Dalbir Singh Sogi 《International Journal of Food Properties》2016,19(2):371-384
Effect of cabinet-drying, vacuum-drying, and freeze-drying methods on the surface hydrophobicity, secondary structure, emulsifying, and foaming properties of protein concentrates prepared from different cultivars of cowpea and Bambara bean was investigated. The vacuum-drying method reduced hydrophobicity, while freeze-dried concentrates presented high hydrophobicity. The concentrates prepared by freeze drying presented more β-sheet (40–43%) and less β-turn (19–24%) structures. Bambara bean protein concentrates prepared by freeze-drying presented higher emulsifying activity (56–59%) compared to those by vacuum-drying and cabinet-drying, while emulsifying activity varied significantly among cultivars of cowpea (46–61%). Protein concentrates prepared by cabinet-drying showed the highest foaming ability. 相似文献
74.
Gwénaëlle Hourdin Alain Germain Claude Moreau François Fajula 《Catalysis Letters》2000,69(3-4):241-244
Ti‐BEA and Ti‐FAU, obtained by post‐synthesis treatment, and TS‐1, obtained by direct hydrothermal synthesis, have been tested
as catalysts for the Ruff oxidative degradation of calcium d‐gluconate to d‐arabinose using diluted hydrogen peroxide as oxidant.
Only large‐pore zeolites Ti‐BEA and Ti‐FAU were found to be active. It was shown, in particular, that a very rapid leaching
of titanium occurred and that the titanium species present in the solution were responsible for the catalytic activity observed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
75.
Nizard Philippe; Chenal Alexandre; Beaumelle Bruno; Fourcade Alain; Gillet Daniel 《Protein engineering, design & selection : PEDS》2001,14(6):439-446
We have shown previously that the diphtheria toxin transmembranedomain (T) may function as a membrane anchor for soluble proteinsfused at its C-terminus. Binding to membranes is triggered byacidic pH. Here, we further characterized this anchoring device.Soluble proteins may be fused at the N-terminus of the T domainor at both extremities, without modifying its membrane bindingproperties. This allows one to choose the orientation of theprotein to be attached to the membrane. Maximum binding to thecell surface is reached within 1 h. Anchoring occurs on cellspreviously treated with proteinase K, suggesting that T interactswith the lipid phase of the membrane without the help of cellsurface proteins. Binding does not permeabilize cells or affectcell viability, despite the fact that it permeabilizes liposomesand alters their structure. When attached to L929 fibroblasts,the proteins are not internalized and remain displayed at theirsurface for more than 24 h. When bound to K562 myeloid cells,the molecules are internalized and degraded. Thus, dependingon the cell type, soluble proteins may be anchored to the surfaceof cells by the T domain for an extended time or directed towardsan internalization pathway. 相似文献
76.
The effluents of wastewater treatment plants (WTTP) discharged into the rivers considerably affect the biogeochemical functioning of the system. In this paper, we characterize both raw and treated domestic wastewater from two WTTPs of Parisian agglomeration using different process treatments (Achères WWTP with a secondary treatment and Colombes WWTP with a tertiary one). In addition to the classical variables, we analyse the input of bacteria, both the heterotrophs and the nitrifyers. Tertiary treatment leads to significantly decrease ammonium-specific load (< 2 g KjN inhab equ.(-1) instead of 9 g KjN inhab equ.(-1) for secondary treatment) and notably reduces the one of organic matter (approximately 2.5 g biological oxygen demand (BOD) inhab equ.(-1) instead of approximately 7.5 g BOD inhab equ.(-1) for secondary treatment); it is therefore promising to improve oxygen status of both the Seine river and its estuary. In terms of total bacterial biomass abatement (the heterotrophs mostly), bioreactors (at Colombes WWTP) eliminate 12% more bacterial biomass than the activated sludge treatment (at Achères WWTP). Regarding the nitrifying bacteria, a tertiary treatment in bioreactors eliminates reverse similar 90% of both nitrifying bacteria and nitrogen pollution of wastewater. Bacterial populations are characterized by large size bacteria (> 1 microm) with a higher growth rate, that represent in the treatment plant effluents 70% of the biomass. These large size bacteria have therefore a strong impact in the organic matter degradation and oxygen consumption. Relationships between classical physical-chemical variables routinely analysed in WWTPs laboratory and bacterial biomass (heterotrophic and nitrifying) are established, in order to quantify the ecological role of the allochthonous bacteria brought into the river system. In addition, domestic specific loads are calculated for both raw and treated effluents of the two types of WWTPs. As the application of the European Water Directive requires to upgrade the wastewater treatment at Achères WWTP as soon as 2007 for 90% nitrification and 30% denitrification and in 2015 for further denitrification (up to 70%), the results of this study can be taken as point-source constraints into the modelling approach already developed for the Seine basin, and chosen to test the implementation of the Water Frame Directive. 相似文献
77.
Donoso-Bravo A Mailier J Martin C Rodríguez J Aceves-Lara CA Vande Wouwer A 《Water research》2011,45(17):5347-5364
Anaerobic digestion enables waste (water) treatment and energy production in the form of biogas. The successful implementation of this process has lead to an increasing interest worldwide. However, anaerobic digestion is a complex biological process, where hundreds of microbial populations are involved, and whose start-up and operation are delicate issues. In order to better understand the process dynamics and to optimize the operating conditions, the availability of dynamic models is of paramount importance. Such models have to be inferred from prior knowledge and experimental data collected from real plants. Modeling and parameter identification are vast subjects, offering a realm of approaches and methods, which can be difficult to fully understand by scientists and engineers dedicated to the plant operation and improvements. This review article discusses existing modeling frameworks and methodologies for parameter estimation and model validation in the field of anaerobic digestion processes. The point of view is pragmatic, intentionally focusing on simple but efficient methods. 相似文献
78.
Stefano Panebianco Klara Berg Jean-Christophe David Mohamed Eid Uwe Filges Friedrich Gröschel Arnaud Guertin Alexander Yu Konobeyev Christian Latgé Sébastien Lemaire Sylvie Leray Alain Letourneau Markus Lüthy Franco Michel-Sendis Selene Scazzi Gediminas Stankunas Nicolas Thiollière Leonhard Tobler Luca Zanini 《Annals of Nuclear Energy》2009
The MEGAPIE project aimed to design, build and operate a liquid metal spallation neutron target of about 1 MW beam power in the SINQ facility at the Paul Scherrer Institut (Villigen, Switzerland). This project is an important step in the roadmap towards the demonstration of the accelerator driven system (ADS) concept and high power liquid metal targets in general. Following the design phase, an experimental program was defined to provide a complete characterization of the facility by performing a “mapping” of the neutron flux at different points, from the center of the target to the beam lines. The neutronic performance of the target was studied using different experimental techniques with the goals of validating the Monte Carlo codes used in the design of the target; additionally, the performance was compared with the solid lead targets used before and after the MEGAPIE experiment. 相似文献
79.
Alain Segundo Potts ;Basilio Thome de Freitas Jr. ;Jose Carlos Amaro 《能源与动力工程:英文版》2014,(7):1272-1278
This paper presents a fuzzy tuning system for real-time industrial PID (proportional-integral-derivative) controllers. The algorithm set the proportional gain, integral time and derivative time of a classical PID structure according to the set point, error and error derivative of the process, respectively. The tuning of the PID controller is based on a fuzzy inference machine. The set of rules of the fuzzy inference machine was obtained by experts engineering. The system is tested in an austempering process but can be applied in any industrial plant. Besides, an analysis between the response of the process with a PID controller and the system of fuzzy auto-tuning for P1D proposed was made. 相似文献
80.
A model for building integrated photovoltaic systems has been developed and implemented in a dynamic simulation tool. This tool takes into account the thermal interactions between the PV collector and the building. The influence of the type of integration upon the PV collector efficiency has been evaluated and hybrid PV/air collectors have been studied. An overall efficiency is defined, including the production of electricity and heat. A case study has been performed on two different typical buildings. In the case of a multi-crystalline silicon PV collector integrated on the roof of a single family house located in Paris, the efficiency of unventilated PV modules fixed on the roof is 14%. If the PV collector is used to preheat the ventilation air, the efficiency reaches 20%. A proper building integration also improves the environmental balance of PV technologies over their life cycle. 相似文献