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Nuclear Science and Techniques 2022年第3期33卷 113-125页

作者： Xiao-Wen Zhu Claude Marchand Olivier Piquet Michel Desmons IRFU CEAUniversite´Paris-Saclay91191 Gif-sur-YvetteFrance

Compact accelerator-based neutron source facilities are garnering attention and play an important and expanding role in material and engineering sciences,as well as in neutron science education and *** are produced by bombarding a low-energy proton beam onto a beryllium or lithium *** such an acceleratorbased neutron source,a radio frequency quadrupole(RFQ)is usually utilized to accelerate a high-intensity proton beam to a few *** study mainly covers the highfrequency structure design optimizations of a 4-vane RFQ with pi-mode stabilizer loops(PISLs)and its RF stability analysis.A 176 MHz RFQ accelerator is designed to operate at a 10%duty factor and could accelerate an80 mA proton beam from 65 keV to 2.5 MeV within a length of 5.3 *** adoption of PISLs ensures high RF stability,eases the operation of the accelerator,and implies less stringent alignment and machining tolerances.

关键词： Accelerator-based neutron source 4-vane RFQ accelerator Pi-mode stabilizer loops Perturbative analysis Electromagnetic design Multipacting simulation

Deformation in the Three Gorges Reservoir after the first impoundment determined by GPS measurements

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Progress in Natural Science:Materials International 2005年第6期15卷 515-522页

作者： DU Ruilin 1,2 , QIAO Xuejun 1,2 *, WANG Qi 1,2 , XING Canfei 1,2 and YOU Xinzhao 1,3 (1. Institute of Seismology, cea, Wuhan 430071, China 2. Laboratory of Crustal Movement and Earth Observation, Wuhan 430071, China 3. Center for Analysis and Prediction, cea, Beijing 100036, China) Institute of Seismology CEA Wuhan 430071 China Laboratory of Crustal Movement and Earth Observation Wuhan 430071 China Center for Analysis and Prediction CEA Beijing 100036 China

A 6-year long GPS observation (1998—2003) indicates that crustal deformation in the Three Gorges area is less active at a marginally measurable rate of 0—5 mm/a relative to stable South China block. However, the impounding water in June 2003 has induced transient displacement at the Three Gorges dam and the emerging reservoir. GPS measurements after the first stage of water filling of the reservoir demonstrate that vertical subsidence close by Yangtze River is about 10—40 mm, and the horizontal displacement is less than 5—10 mm. The maximum subsidence induced by the impoundment is located in the segment of the reservoir from Maoping to Xiangxi. The water loading-induced deformation diminishes rapidly with the distance from banks of the reservoir. The overall pattern of transient deformation is consistent with the simulation result of Farrell, and is attributed to the elastic response of upper lithosphere crust to overlying water reservoir.

关键词： Three Gorges GPS impoundment deformation.

Recent Results of LHCD Experiments in EAST

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Plasma Science and Technology 2011年第2期13卷 153-156页

作者：丁伯江孔二华李妙辉秦永亮张磊 A.EKEDAHL Y.PEYSSON 王茂徐旵东胡怀传黄懿云徐国盛单家方刘甫坤赵燕平高翔万宝年李建刚 Institute of Plasma Physics Chinese Academy of Sciences cea/IRFM Cadarache 13108

Lower hybrid wave （LHW）-plasma coupling and lower hybrid current drive （LHCD） experiments in divertor, including single-null and double-null, and limiter configurations were conducted systematically in EAST. A maximum power for launched LHW is 1.4 MW and the plasma current with LHCD is about 1 MA. It is indicated that the coupling is best in limiter configuration, then in single-null one, while worst in double-null one. Study in current drive efficiency by a least squares fit shows that there is no obvious difference in drive efficiency between the double-null and the single-null cases, whereas the efficiency is a slightly lower in the limiter case. The effect of plasma density on the current drive efficiency is due to the influence of density on impurity concentration.

关键词： LHCD LHW-plasma coupling configuration

Preliminary investigation of seismic damage to two steel space structures during the 2013 Lushan earthquake

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Earthquake Engineering and Engineering Vibration 2013年第3期12卷 497-500页

作者： Dai Junwu Qu Zhe Zhang Chenxiao Weng Xuran Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsCEA

Severe damage to steel space structures is rarely reported when compared to other structural systems damaged during past major earthquakes around the world. Two gymnasiums of steel space structures in downtown Lushan County that were damaged during the 2013 M7.0 Lushan earthquake in China were investigated and the observations are summarized in this paper. Typical damage to these two steel space structures ranges from moderate to severe. Moderate damage includes global buckling and dislocation of bolted connections of truss members, and inelastic elongation of anchor bolts and sliding of pedestal plates of supports. Severe damage includes member fracture caused by local buckling, and fracture failure of anchor bolts and welds. The distribution of structural damage to these two structures is described in detail and future research opportunities are suggested.

关键词： Lushan earthquake steel space structure gymnasitun seismic damage member buckling fracture failure

A Colocalized Scheme for Three-Temperature Grey Diffusion Radiation Hydrodynamics

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Communications in Computational Physics 2022年第1期31卷 293-330页

作者： R.Chauvin S.Guisset B.Manach-Perennou L.Martaud cea DAMDIFF-91297 ArpajonFrance

A positivity-preserving, conservative and entropic numerical scheme is presented for the three-temperature grey diffusion radiation hydrodynamics model. Moreprecisely, the dissipation matrices of the colocalized semi-Lagrangian scheme are de-fined in order to enforce the entropy production on each species (electron or ion) proportionally to its mass as prescribed in [34]. A reformulation of the model is then considered to enable the derivation of a robust convex combination based scheme. Thisyields the positivity-preserving property at each sub-iteration of the algorithm whilethe total energy conservation is reached at convergence. Numerous pure hydrodynamics and radiation hydrodynamics test cases are carried out to assess the accuracy of themethod. The question of the stability of the scheme is also addressed. It is observedthat the present numerical method is particularly robust.

关键词： Colocalized Lagrangian scheme radiation hydrodynamics grey diffusion discrete entropy production plasma physics simulations

25 Gbps low-voltage hetero-structured silicongermanium waveguide pin photodetectors for monolithic on-chip nanophotonic architectures

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Photonics Research 2019年第4期7卷 437-444页

作者： DANIEL BENEDIKOVIC LéOPOLD VIROT GUY AUBIN FARAH AMAR BERTRAND SZELAG BAYRAM KARAKUS JEAN-MICHEL HARTMANN CARLOS ALONSO-RAMOS XAVIER LE ROUX PAUL CROZAT ERIC CASSAN DELPHINE MARRIS-MORINI CHARLES BAUDOT FRéDéRIC BOEUF JEAN-MARC FéDéLI CHRISTOPHE KOPP LAURENT VIVIEN Centre de Nanosciences et de Nanotechnologies CNRS University of Paris-Sud Université Paris-Saclay University Grenoble Alpes and cea LETI Minatec Campus Technology R&D STMicroelectronics SAS

Near-infrared germanium(Ge) photodetectors monolithically integrated on top of silicon-on-insulator substrates are universally regarded as key enablers towards chip-scale nanophotonics, with applications ranging from sensing and health monitoring to object recognition and optical communications. In this work, we report on the highdata-rate performance pin waveguide photodetectors made of a lateral hetero-structured silicon-Ge-silicon(Si-Ge-Si) junction operating under low reverse bias at 1.55 μm. The pin photodetector integration scheme considerably eases device manufacturing and is fully compatible with complementary metal-oxide-semiconductor technology. In particular, the hetero-structured Si-Ge-Si photodetectors show efficiency-bandwidth products of^9 GHz at-1 V and ~30 GHz at-3 V, with a leakage dark current as low as ~150 nA, allowing superior signal detection of high-speed data traffic. A bit-error rate of 10-9 is achieved for conventional 10 Gbps, 20 Gbps, and25 Gbps data rates, yielding optical power sensitivities of-13.85 dBm,-12.70 dBm, and-11.25 dBm, respectively. This demonstration opens up new horizons towards cost-effective Ge pin waveguide photodetectors that combine fast device operation at low voltages with standard semiconductor fabrication processes, as desired for reliable on-chip architectures in next-generation nanophotonics integrated circuits.

关键词： germanium(Ge) photodetectors chip-scale nanophotonics waveguide photodetectors

Highly selective sorting of semiconducting single wall carbon nanotubes exhibiting light emission at telecom wavelengths

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Nano Research 2016年第8期9卷 2478-2486页

作者： Francesco Sarti Francesco Biccari Federica Fioravanti Ughetta Torrini Anna Vinattieri Vincent Derycke Massimo Gurioli Arianna Filoramo Department of Physics and LENS University of Florence Via Sansone 1 50019 Sesto Fiorentino Italy LICSEN NIMBE CEA CNRS University Paris-Saclay CEA Saclay 91191 Gif sur Yvette CEDEX France

Single wail carbon nanotubes （SWNTs） are known for their exceptional electronic properties. However, most of the synthesis methods lead to the production of a mixture of carbon nanotubes having different chiralities associated with metallic （m-SWNTs） and semiconducting （s-SWNTs） characteristics. For application purposes, effective methods for separating these species are highly desired. Here, we report a protocol for achieving a highly selective separation of s-SWNTs that exhibit a fundamental optical transition centered at 1,550 nm. We employ a polymer assisted sorting approach, and the influence of preparation methods on the optical and transport performances of the separated nanotubes is analyzed. As even traces of m-SWNTs can critically affect performances, we aim to produce samples that do not contain any detectable fraction of residual m-SWNTs.

关键词： single wall carbonnanotube (SWNT) sorting optical properties field effect transistors

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长的中波红外HgCdTe平接线列阵(上)

红外 1999年第4期20卷 5-9页

作者： Jean Paul Chamonal 高国龙法国leti/LIR(cea)

高分辨率红外成像系统需要非常长的扫描线列,这些扫描列阵不但具有数千个探测器,而且具有高的性能。本文介绍法国leti/LIR在长平接列阵方面所取得的最新技术进展,并给出了在一个间距为30μm、截止波长为5.5μm的1500元HgCdTe探测器线列... 详细信息

高分辨率红外成像系统需要非常长的扫描线列,这些扫描列阵不但具有数千个探测器,而且具有高的性能。本文介绍法国leti/LIR在长平接列阵方面所取得的最新技术进展,并给出了在一个间距为30μm、截止波长为5.5μm的1500元HgCdTe探测器线列上获得的结果。这个非常大的列阵(长度≈50mm)有一个间接混成体系结构,该体系结构由5个平接的HgCdTe光伏探测电路和5个Si CMOS读出电路组成,它被混成在一块用机械方法加以精密匹配的扇出衬底上。至于探测器间距,无缺陷切割和平接都是用精确的无损技术进行的。介绍了该列阵的详细情况和主要电-光学性能。

关键词：红外线列平接焦平面列阵汞镉碲

Electrochemical reactivity of In-Pb solid solution as a negative electrode for rechargeable Mg-ion batteries

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Journal of Energy Chemistry 2021年第4期30卷 124-128页

作者： Lucie Blondeau Suzy Surble Eddy Foy Hicham Khodja Magali Gauthier UniversitéParis-Saclay CEACNRSNIMBELEEL91191Gif-sur-YvetteFrance UniversitéParis-Saclay CEACNRSNIMBELAPA-IRAMAT91191Gif-sur-YvetteFrance

A composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb solid solution towards Mg.A potential synergetic coupling of electroactive elements In and Pb was examined using electrochemical and ex situ X-ray diffraction *** potential profile of the solid solution indicates the formation of Mg_(2)Pb and Mg ***,the diffraction study suggests a peculiar electrochemically-driven amorphization of Mg In during the magnesiation,in strong contrast to Mg In crystallization in In-based and In Bi-based electrodes reported in the *** In and Pb favors the amorphization of Mg In and a high first magnesiation capacity of about 550 m Ah g^(-1),but is thereafter detrimental to the material’s *** results emphasize the possible influence of electrochemically-driven amorphization and crystallization processes on electrochemical performance of battery materials.

关键词： Magnesium battery Negative electrode Alloy Amorphization

Crustal Deformation Derived from GPS in the Chinese Mainland from 1991-2004

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Earthquake Research in China 2015年第2期29卷 225-236页

作者： Cao Jianling Wang Hui Wu Yanqiang Liu Xiaoxia Zhang Jing Key Laboratory of Earthquake Prediction cea First Crust Monitoring and Application Center cea Institute of Earthquake Science cea

Based on GPS data from 1991- 2004 and the least-squares collocation method,we analyze the crustal deformation in the Chinese mainland. The results show that the first-order crustal deformation is unchanged in different periods in the Chinese mainland,which reflects the background of regional tectonic activity. The strain rate is much higher in Western China,especially in the Qinghai-Tibetan Plateau and Sichuan-Yunnan area. The variations in different periods are related with seismicity of strong earthquakes during the same time. The GPS data after 2004 shows the post-seismic deformation of the 2001 Kunlun Mountains M S8. 1 earthquake.

关键词： Chinese mainland GPS Present-day crustal deformation Least squaresCollocation