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排序方式: 共有791条查询结果,搜索用时 31 毫秒
31.
Luiz A.O. Rocha Sylvie Lorente Adrian Bejan Ren Anderson 《International Journal of Heat and Mass Transfer》2012,55(25-26):7832-7837
Here we show that the heat transfer between a pipe assembly and the soil during the annual temperature cycle of a heat pump depends on the configuration of the flow system. We rely on constructal design to find the flow architecture (spacings, shapes) such that the heat transfer between the assembly and the ground is increased. The flow configuration changes freely, and its design is evolutionary. The better shapes change gradually from slender to square as the volume fraction occupied by the flow assembly increases. The heat transfer performance increases as the depth of the structure decreases, but the depth has a negligible effect on the shape of the structure. The results also show that the heat transfer performance increases as the configuration of the ground volume and the buried structure evolves to the most slender shape possible. 相似文献
32.
Balasubramanian Nagarajan Sylvie Castagne Zhongke Wang H.Y. Zheng Kartikeyan Nadarajan 《International Journal of Material Forming》2017,10(1):109-123
Flexible Pad Laser Shock Forming (FPLSF) is a new microforming process using laser-induced shock pressure and a hyperelastic flexible pad to induce high strain-rate (~105 s?1) plastic deformation on metallic foils to produce 3D microcraters. This paper studies the effect of two significant process parameters of FPLSF, flexible pad material and its thickness, on the deformation characteristics of the metal foils using experiments and finite element analysis. A finite element model is developed to simulate the FPLSF process. The stress-strain distribution across the foil and the flexible pad at different process stages of FPLSF are studied using FE analysis. Flexible pad materials including silicone rubber, polyurethane rubber, and natural rubber with thicknesses ranging between 300 μm and 3000 μm have been investigated in detail. Experimental results highlight that both the hardness and thickness of the flexible pad significantly influence the deformed crater geometry, thickness distribution across the formed crater and surface hardness at the crater surfaces. The experimental results are correlated with the stress-strain distributions from finite element analysis to study the underlying behaviors. 相似文献
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Initial Molecular Recognition Steps of McjA Precursor during Microcin J25 Lasso Peptide Maturation 下载免费PDF全文
Dr. Nadine Assrir Dr. Anna Pavelkova Régine Dazzoni Dr. Rémi Ducasse Dr. Nelly Morellet Dr. Eric Guittet Prof. Sylvie Rebuffat Dr. Séverine Zirah Dr. Yanyan Li Dr. Ewen Lescop 《Chembiochem : a European journal of chemical biology》2016,17(19):1851-1858
Microcin J25 (MccJ25) has emerged as an excellent model to understand the maturation of ribosomal precursor peptides into the entangled lasso fold. MccJ25 biosynthesis relies on the post‐translational modification of the precursor McjA by the ATP‐dependent protease McjB and the lactam synthetase McjC. Here, using NMR spectroscopy, we showed that McjA is an intrinsically disordered protein without detectable conformational preference, which emphasizes the active role of the maturation machinery on the three‐dimensional folding of MccJ25. We further showed that the N‐terminal region of the leader peptide is involved in interaction with both maturation enzymes and identified a predominant interaction of V43–S55 in the core McjA sequence with McjC. Moreover, we demonstrated that residues K23–Q34 in the N‐terminal McjA leader peptide tend to adopt a helical conformation in the presence of membrane mimics, implying a role in directing McjA to the membrane in the vicinity of the lasso synthetase/export machinery. These data provide valuable insights into the initial molecular recognition steps in the MccJ25 maturation process. 相似文献
35.
An overview of recent developments in volatile compounds analysis from edible oils: Technique‐oriented perspectives 下载免费PDF全文
36.
Analysis of target volatile compounds related to fishy off‐flavor in heated rapeseed oil: A comparative study of different headspace techniques 下载免费PDF全文
37.
Benoit Igne Jean-Michel Roger Sylvie Roussel Vronique Bellon-Maurel Charles R. Hurburgh 《Chemometrics and Intelligent Laboratory Systems》2009,99(1):57-65
Eight calibration transfer methods based on the removal of orthogonal signal were compared for the standardization of whole soybean protein and oil models. Dynamic orthogonal projection (DOP), transfer by orthogonal projection (TOP), error removal by orthogonal subtraction (EROS), orthogonal signal correction (OSC), and orthogonal projections to latent structures (O-PLS) as well as the modification and extension of some of these methods were compared in the transfer of models in intra and inter-brand situations using two Foss Infratecs and two Bruins OmegAnalyzerGs. For each brand, a master was designated and its models transferred onto the second unit of its network and the two units of the second brand. Calibration models were transferable from brand to brand with similar or better precision than when each instrument was calibrated on its own calibration set (for Infratec 1229, the relative predictive determinant (RPD) increased in intra and inter-brand calibration transfer situations from 10.42 to 11.45 and 10.57, with DOP and EROS respectively). Performance of each method was different across parameters, instruments, and validation sets. DOP modifications on the determination of the difference matrix showed promising results while TOP and EROS extensions to include variability specifically present in certain crop years did not bring any beneficial effects. 相似文献
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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
40.
Séverine A.E. Boyer Michel Gerland Sylvie Castagnet 《Polymer Engineering and Science》2014,54(9):2139-2146
The influence of gas sorption on damage nucleation of a semicrystalline polymer during coupled diffuso‐mechanical monotonic loading in tension was investigated for the first time. Alpha‐poly(vinylidene fluoride) was mechanically strained under the presence of two chemically different gases, hydrogen and carbon dioxide, at a temperature of 30°C and a pressure up to 120 bar. The cavitation damage at the microstructure scale after gas decompression was assessed from a careful SEM and TEM micrographs analysis. Compared with SEM, TEM allowed quantifying the smallest cavities (ten‐nanometer size). If decompression in hydrogen appeared to have only a slight effect on cavitation however, carbon dioxide showed a detrimental effect on damage nucleation with the exhibition of a significant population of small cavities. On the other hand, tension under gas pressure is more sensitive to hydrogen than to carbon dioxide. Once interaction with gaseous carbon dioxide takes place the plasticizing effect is in competition with damage by cavitation. POLYM. ENG. SCI., 54:2139–2146, 2014. © 2013 Society of Plastics Engineers 相似文献