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Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot Julien G.Moreau Jérôme Neauport cea CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

GPS DATA INVERSION OF KINEMATIC MODEL OF MAIN FAULTS IN YUNNAN

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大地测量与地球动力学 2003年第B12期23卷 62-68页

作者： Shen Chongyang, Wu Yun, Wang Qi, You Xinzhao and Qiao Xuejun (Institute of seismology, cea, Wuhan 430071, China) Institute of seismology CEA Wuhan 430071 China

On the basis of GPS observations in Yunnan from 1999 to 2001, we adopt the robust Bayesian least square estimation and multi fault dislocation model to analyze the quantitative kinematics models of the main faults in Yunnan. The geodetic inversion suggests that: (1) The horizontal movement of crust in Yunnan is affected distinctly by fault activity whose characters are consistent with geological results; (2) The activity of the north segment of the Red River fault zone is maximum, in the middle segment is moderate, and in the south segment is minimum; (3)Among others, the Xiaojiang fault zone has the strongest activity, the secondary are the Lancang fault zone and the north segment of Nujiang fault zone, the Qujiang fault zone shows the characteristic of hinge fault; (4)Each fault could produce an earthquake of M s=6 more or less per year; (5) The larger value of maximum shear strain are mostly located along the main active fault zones and their intersections; earthquakes did not occur at the place of maximum shear strain, and mostly take place at the higher gradient zones, especially at its corner.

关键词：云南 GPS数据断层运动动态模型非线形逐步逼近反向方法最大切变应力观测数据

Some Thoughts on the Earthquake Science Experimental Site——The Underground Cloud Map

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Earthquake Research in China 2019年第1期33卷 1-8页

作者： CHEN Yong XU Yihe CAI Huiteng LI Wen School of Earth Sciences and Engineering Nanjing University Institute of Earthquake Forecasting CEA Key Laboratory of Seismic Observation and Geophysical Imaging Institute of GeophysicsCEA Fujian Earthquake Agency Geophysical Exploration Center CEA

The Western Yunnan Earthquake Predication Test Site set up jointly by the China Earthquake Administration,the National Science Foundation Commission of America,and United States Geological Survey has played an important role in development of early earthquake research work in China. Due to various objective reasons, most of the predicted targets in the earthquake prediction test site have not been achieved,and the development has been hindered. In recent years, the experiment site has been reconsidered,and renamed the "Earthquake Science Experimental Site". Combined with the current development of seismology and the practical needs of disaster prevention and mitigation,we propose adding the "Underground Cloud Map"as the new direction of the experimental site. Using highly repeatable, environmentally friendly and safe airgun sources,we could send constant seismic signals,which realizes continuous monitoring of subsurface velocity changes. Utilizing the high-resolution 3-D crustal structure from ambient noise tomography,we could obtain 4-D (3-D space+1-D time) images of subsurface structures, which we termed the "Underground Cloud Map". The"Underground Cloud Map" can reflect underground velocity and stress changes,providing new means for the earthquake monitoring forecast nationwide,which promotes the conversion of experience-based earthquake prediction to physics-based prediction.

关键词： Earthquake Science Experimental Site The Underground Cloud Map 4-D seismology Airgun

Chitosan-mediated synthesis of carbon nanotube-gold nanohybrids

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Science China Chemistry 2010年第9期53卷 2015-2018页

作者： GRAVEL Edmond FOILLARD Stéphanie DORIS Eric cea iBiTecSService de Chimie Bioorganique et de Marquage

Metal-nanotube nanohybrids were produced by in situ synthesis and stabilization of gold nanoparticles on chitosan-functionalized carbon *** formation of gold nanoparticles from tetrachloroauric acid was observed after only a few minutes of contact with the functionalized nanotubes,at room *** results suggest that adsorption of chitosan at the surface of carbon nanotubes permits smooth reduction of the metallic salt and efficient anchoring of gold nanoparticles to the nanotubes.

关键词： nanohybrid carbon nanotube gold nanoparticle

Monolithic crystalline silicon solar cells with SiN_x layers doped with Tb^(3+) and Yb^(3+) rare-earth ions

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Journal of Rare Earths 2019年第5期37卷 515-519页

作者： Ing-Song Yu Shao-Chun Wu Lucile Dumont Julien Cardin Christophe Labbé Fabrice Gourbilleau Department of Materials Science and Engineering National Dong Hwa University CIMAP CNRS/cea/ENSICAEN/Université de Caen Normandie

In this study, we propose the fabrication of monolithic crystalline silicon solar cells with Tb^(3+) and Yb^(3+)-doped silicon nitride(SiN_x) layers by low-cost screen-printing methods. The performances of c-Si solar cells can be enhanced by rare-earth ions doped SiN_x layers via the mechanism of spectrum *** SiN_x doped and codoped thin films were deposited by reactive magnetron co-sputtering and integrated as the antireflection coating layers in c-Si solar cells. The characterizations of SiN_x, SiN_x:Tb^(3+) tand SiN_x:Tb^(3+)-Yb^(3+) thin films were conducted by means of photoluminescence, Rutherford backscattering spectroscopy, Ellipsometry spectroscopy and Fourier transform infrared measurements. Their composition and refractive index was optimized to obtain good anti-reflection coating layer for c-Si solar *** electron microscopy performs the uniform coatings on the textured emitter of c-Si solar cells. After the metallization process, we demonstrate monolithic c-Si solar cells with spectrum conversion layers, which lead to a relative increase by 1.34% in the conversion efficiency.

关键词： Crystalline silicon solar cell Spectrum conversion Silicon nitride Down-shifting Rare-earth ion Anti-reflection coating

Intermediate to Long-term Estimation of Strong Earthquake Risk Areas in the Chinese Mainland Based on Geodesic Measurements

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Earthquake Research in China 2018年第2期32卷 153-172页

作者： Zhang Jing Zhu Yiqing Wu Yanqiang Zhang Xi Yang Guohua Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingCEABeijing 100036China The First Monitoring and Application Center CEATianjin 300180China The Second Monitoring and Application Center CEAXi'an 710054China

Based on previous research results,present-day crustal deformation and gravity fields in the Chinese mainland are analyzed using the GPS data,leveling,gravity and cross-fault deformations. We analyzed strain accumulation of the major faults,and identified locked or high strain accumulation segments. Combining the effects of large earthquakes in the study area,the long-term (decade) probability of large earthquakes in the Chinese mainland is estimated.

关键词： Estimation of earthquake risk area Geodetic measurement The Chinese mainland

QUAD METHOD FOR IDENTIFYING RELATIVELY STABLE STATIONS

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大地测量与地球动力学 2003年第B12期23卷 23-29页

作者： Huang Liren (First Crust Monitoring and Application Center, cea, Tianjin 300180,China) FirstCrustMonitoringandApplicationCenter，cea，Tianjin300180，China

The QUAD(Quasi-Accurate Detection of gross errors) method which is originally developed to detect gross errors in the geodetic data is extended and used to select and identify relatively stable stations. The formulas and algorithm are described in detail. Some problems that should be noticed in the use of this method are discussed. Finally, this method is applied to some data observed in North China as an example.

关键词： GPS测量稳定测点 QUAD方法误差的亚精确测定 QUAD方法的特殊问题

Effects of the February 12,2014 M_S 7.3 Yutian Earthquake on Seismicity of the Northeastern Edge of Qinghai-Tibetan Block

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Earthquake Research in China 2015年第2期29卷 158-168页

作者： Wang Shuangxu Jiang Fengyun Zhang Sixin Zhou Cong Second Crust Monitoring and Application Center CEA

First of all,using the GPS velocity field from campaign GPS measurements implemented by CMONC( C hina Crustal Movement Observation) a nd TEONC( C hina Tectonic Environment Observation Networks) u p to 2013, w e analyzed the background of regional crustal horizontal movement and deformation before the M S7. 3 Yutian,Xinjiang earthquake on February 12,2014. Then,by comparing this to the vertical movement from leveling measurements,we studied the crustal movement deformation and the state of strain accumulation on the northeastern edge of Qinghai-Tibetan ***,we investigated the possible effects on the earthquake activity of the northeastern edge of Tibet from the M S7. 3 Yutian earthquake. The result indicates that,the M S7. 3Yutian earthquake occurred against the background of strong tectonic movement and intensive intracontinental crustal differential movement on the edges of tectonic blocks in western China,and also that it happened in the period of the strong tectonic stress field in Qinghai-Tibetan block and its edges. The sinistral strike-slip and stress transfer of the Yutian M S7. 3 earthquake may accelerate the rupture of fault segments with high strain accumulation at the northeastern edge of Qinghai-Tibetan block( especially in Qilian Mountain fault zone,and border area of Gansu,Qinghai and Sichuan provinces on the south of western Qinling).

关键词： Seismicity The 2014 Yutian Ms7.3 earthquake Crustal movement anddeformation Stress accumulation The northeastern edge of Qinghai-Tibetan block

tuning the properties of confined water in standard and lybrid nanotubes： An infrared spectroscopic study

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Nano Research 2018年第9期11卷 4759-4773页

作者： Yuanyuan Liao Pierre Picot Maxime Laine Jean-Blaise Brubach Pascale Roy Antoine Thill Sophie Le Caer LIONS NIMBE UMR 3685 CEA CNRS Universite Paris-Saclay CEA Saclay Bt. 546 F-91191 Gif-sur-Yvette Cedex France Synchrotron SOLEIL AILES Beamline L'Orme des Mefisier Saint-Aubin BP 48 F-91192 Gif-sur-Yvette Cedex France

Imogolite is a natural nanotubular aluminum silicate clay mineral found in volcanic soils. Its well-defined, tunable structure makes it a good candidate for studying water confinement in a one-dimensional （1D） structure. Water confinement in self-sustaining imogolite thin films was studied using infrared spectroscopy. Two types of synthetic imogolites were investigated： pristine imogolite （IMO-OH） with a hydrophilic inner surface covered with Si-OH groups and hybrid imogolite （IMO-CH3） with a hydrophobic inner surface covered with Si-CH3 groups. Both imogolites have an outer surface that is covered with Al-OH groups. Infrared spectra were recorded in the 20-4,000 cm^-1 spectral range as a function of relative humidity. Analysis of the O-H stretching band provides information on the H bonding of confined water molecules inside and outside the IMO-OH tubes. The scenario for water filling as a function of relative humidity is determined for both systems. Adsorption begins in the IMO-OH tubes at the lowest relative humidity （〈 10%）. The inner surface of the tubes is first covered with water molecules; then, the central part of the tubes is filled, leading to very strong H bonds and a structured spectrum. In contrast, the H bonds of water adsorbed on the outer surfaces of these tubes are weaker. A different scenario is observed for water inside IMO-CH3： Weakly H-bonded water molecules are present, similar to that observed in carbon nanotubes. Water confinement in imogolites is governed by the hydrophilicity of the inner walls. At similar partial pressures, the degree of H bonding depends on the interactions between water and the nanotube wall.

关键词： imogolite nanotubes confinement infrared spectroscopy water isotherms hydrophilic hydrophobic