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51.
Josée Drillet Nathalie Valle Thierry Iung 《Metallurgical and Materials Transactions A》2012,43(13):4947-4956
The current trend toward producing lighter vehicles in the automotive industry is driven by the need to conform to the new exhaust emission control regulations. This objective presents a challenge to steel manufacturers. The difficulty lies in designing new alloys with an optimum strength/formability/cost balance for the various components. Here, the key to success lies in controlling the steel microstructure and especially the phase transformations at the smallest possible scale. Among the different alloying elements, light elements such as carbon and boron are of prime importance due to their major effects on the kinetics of phase transformations. Characterization tools combining high spatial and analytical resolution such as secondary ion mass spectrometry (SIMS) and field emission gun-transmission electron microscopy (TEM) were used. In this article, the examples presented are as follows. (1) Boron segregation and precipitation effects to control hardenability in martensitic steels. (2) Local carbon distribution in advanced high-strength steels, with a specific emphasis on martensite tempering. Links have been established between the boron and carbon distribution and the formability. 相似文献
52.
Thermal Resonance at the Microscale in AC Scanning Thermal Microscopy with a Thermal-Resistive Probe
Olivier Rapha?l Nathalie Trannoy Philippe Grossel 《International Journal of Thermophysics》2012,33(7):1259-1269
Investigation of the thermal-resistive probe response in an AC scanning thermal microscope (SThM) as a function of the distance probe–material surface under ambient conditions and the current excitation frequency is presented. The analysis of temperature experimental results points out a phenomenon which can be interpreted as a thermal wave resonance. The modeling of the thermal response with the finite element method considering the surrounding medium as a thermally conducting medium tends to confirm this. This phenomenon is independent of the sample nature and is related to the thermal diffusion length of the air medium between the probe and the sample. An equivalent resonance factor is defined: it shows a linear dependence with the characteristic distance for which the thermal resonance phenomenon is an extremum. The system—probe/sample surface—behaves as a resonant cavity at the microscale. This configuration is not specific to a SThM and can occur within electronic devices. 相似文献
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54.
Sofiane Aloui Nicolas Delaunay Eric Kerherve Nathalie Deltimple Robert Plana Didier Belot 《Analog Integrated Circuits and Signal Processing》2012,70(2):203-211
A millimeter-wave Power Amplifier (PA) based on a 65nm CMOS technology from STMicroelectronics has been designed. The targeted
feature is the unlicensed band around 60 GHz suitable for wireless personal area network application (WPAN). To optimize the
linearity, the PA is designed under class A biasing to have an output compression point (OCP1) close to its saturated Power (P
sat). S-parameters and large signal measurement results are demonstrated and compared with electromagnetic simulations. The PA
offers a P
sat of 8.3 dBm, an OCP1 of 6 dBm and a gain of 6.7 dB. The die area is 0.29 mm2 with pads. Considering those results, one-tone simulations are not sufficient to characterize the linearity performances
of the PA in its real conditions of use. Consequently, two-tone simulations are firstly performed. After, linearity figures
of merit (FoM) are discussed applying an orthogonal frequency-division multiplexing (OFDM) modulated signal. The PA offers
an adjacent channel power ratio (ACPR) of 15 dB and an error vector magnitude (EVM) of 20% at PA compression operating mode. 相似文献
55.
WANG Jiang FAUTRELLE Yves REN Zhong-ming LI Xi NGUYEN-THI Henri MANGELINCK-NOEL Nathalie SALLOUM ABOU JAOUDE Georges ZHONG Yun-bo KALDRE Imants BOJAREVICS Andris BULIGINS Leonid 《钢铁研究学报(英文版)》2012,(Z1):381-385
Sn-3wt%Pb alloy was directionally solidified without and with a 0.08T transverse magnetic field(TMF),and real-time recorded by in-situ synchrotron X-ray imaging.Results indicate that TMF shortened the distance from the location of nucleation to the advancing interface,and accelerated the growth rate of the equiaxed crystal,which caused the columnar-to-equiaxed transition(CET)finally.The thermoelectromagnetic convection(TEMC)in front of the interface and around the crystal’s dendritic branch should respond to changes of the distance and the growth rate. 相似文献
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57.
Discovery of Heterocyclic Nonacetamide Synaptic Vesicle Protein 2A (SV2A) Ligands with Single‐Digit Nanomolar Potency: Opening Avenues towards the First SV2A Positron Emission Tomography (PET) Ligands 下载免费PDF全文
Joël Mercier Laurence Archen Véronique Bollu Stéphane Carré Yves Evrard Dr. Eric Jnoff Dr. Benoît Kenda Bénédicte Lallemand Dr. Philippe Michel Dr. Florian Montel Dr. Florence Moureau Nathalie Price Dr. Yannick Quesnel Dr. Xavier Sauvage Dr. Anne Valade Dr. Laurent Provins 《ChemMedChem》2014,9(4):693-698
The role of the synaptic vesicle protein 2A (SV2A) protein, target of the antiepileptic drug levetiracetam, is still mostly unknown. Considering its potential to provide in vivo functional insights into the role of SV2A in epileptic patients, the development of an SV2A positron emission tomography (PET) tracer has been undertaken. Using a 3D pharmacophore model based on close analogues of levetiracetam, we report the rationale design of three heterocyclic non‐acetamide lead compounds, UCB‐A, UCB‐H and UCB‐J, the first single‐digit nanomolar SV2A ligands with suitable properties for development as PET tracers. 相似文献
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59.
Manhal Abouzlam Régis Ouvrard Driss Mehdi Florence Pontlevoy Bertrand Gombert Nathalie Karpel Vel Leitner Sahidou Boukari 《Control Engineering Practice》2013,21(1):105-112
This paper deals with the control of a wastewater treatment pilot by catalytic ozonation. In general, catalytic ozonation processes operate with a deliberate ozone overproduction to obtain a treated water which respects discharge standards. But, in this case, the oxygen consumption is not optimal and the operating costs are important. The objective of this study focuses on the optimization of the catalytic ozonation reactor. A continuous-time transfer function model is identified to represent the pilot behavior, and an optimal control is proposed to obtain a significant abatement of the pollutant. In this application, the pollutant abatement is represented by the absorbance. 相似文献
60.
Yong‐Ning Zhou Mahsa Sina Nathalie Pereira Xiqian Yu Glenn G. Amatucci Xiao‐Qing Yang Frederic Cosandey Kyung‐Wan Nam 《Advanced functional materials》2015,25(5):696-703
Searching high capacity cathode materials is one of the most important fields of the research and development of sodium‐ion batteries (SIBs). Here, we report a FeO0.7F1.3/C nanocomposite synthesized via a solution process as a new cathode material for SIBs. This material exhibits a high initial discharge capacity of 496 mAh g?1 in a sodium cell at 50 °C. From the 3rd to 50th cycle, the capacity fading is only 0.14% per cycle (from 388 mAh g?1 at 3rd the cycle to 360 mAh g?1 at the 50th cycle), demonstrating superior cyclability. A high energy density of 650 Wh kg?1 is obtained at the material level. The reaction mechanism studies of FeO0.7F1.3/C with sodium show a hybridized mechanism of both intercalation and conversion reaction. 相似文献