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chinese Science Bulletin 1998年第10期43卷 837-840页

作者： xu yigang guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

Spinel peridotite xenoliths from Wangqing, NE china exhibit correlative variations in texture, temperature, geochemistry and radiogenic isotopes. This suggests that the Wangqing xenoliths may come from a mantle diapir. It is possible that the fertile and undeformed lherzolites were situated in the interior of the diapir, whereas the refractory and deformed harzburgites and clinopyroxene_poor lherzolites were within the diapiric flanks.

关键词： peridotite xenoliths texture geochemistry Wangqing.

Trace element characteristics and origin of intergranular components in mantle peridotites

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chinese Science Bulletin 2000年第7期45卷 643-649页

作者： xu yigangguangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

Leaching experiment has been carried out on mantle xenoliths with different petrographic features in order to directly characterize the nature of intergranular components. ICP-MS analyses of leachates show that they are characterized by high LREE concentrations with strong depletion of Ta. The total REE contents and whether the negative Rb, Ba and Nb anomalies are present or not in intergranular components are largely dependent upon the nature of mantle metasomatism experienced by its host rock. It is proposed that intergranular components may represent residues of small volume metasomatic melts.

关键词： peridotite xenoliths intergranular components trace elements upper mantle.

Summary of the 11th Conference on Magnetic Confined Fusion Theory and Simulation

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Plasma Science and Technology 2024年第10期26卷 1-7页

作者： guangzhou HAO Jianqiang xu Youwen SUN Zhibin GUO Organizing Committee of the 11th Conference on Magnetic Confined Fusion Theory and Simulation Southwestern institute of Physics Chengdu 610041People’s Republic of China institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China State Key Laboratory of Nuclear Physics and Technology Fusion Simulation CenterSchool of PhysicsPeking UniversityBeijing 100871People’s Republic of China 不详

This conference report summarizes recent progress in plasma theory and simulation that was presented in contributed papers and discussions at the 11th Conference on Magnetic Confined Fusion Theory and Simulation(CMCFTS)held in Chengdu,china,27–30 October,*** in various fields has been *** example,results on zonal flow generation by mode coupling,simulations of the key physics of divertor detachment,energetic particle effects on magnetohydrodynamic(MHD)modes in addition to ion-and electron-scale turbulence,physics of edge coherent modes and edge-localized modes,and the optimization of ion heating schemes as well as confinement scenarios using advanced integrated modeling are presented at the *** this conference,the scientific research groups were organized into six categories:(a)edge and divertor physics;(b)impurity,heating,and current drive;(c)energetic particle physics;(d)turbulent transport;(e)MHD instability;and(f)integrated modeling and code development.A summary of the highlighted progress in these working groups is presented.

关键词： magnetic confined fusion(MCF) theory and simulation modeling tokamak

Synthesis of Organic-Inorganic Hybrid Aluminum Hypophosphite Microspheres Flame Retardant and Its Flame Retardant Research on Thermoplastic Polyurethane

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 221-233页

作者：刘生鹏 xu Zhi ZHANG Xinyuan WEI Huan XIONG Yun DING yigang HUANG Wenbo 许莉莉 Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Key Laboratory for Green Chemical Process of Ministry of EducationSchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430205China Hubei Three Gorges Laboratory Yichang 443007China School of Technology Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China

Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)(PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres(PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane(TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric(TG), limited oxygen index tests(LOI), and cone calorimeter test(CCT). The TPU composite achieved vertical burning(UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate(pHRR) and total heat release(THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites.

关键词： polyphosphazene thermoplastic polyurethane flame retardancy aluminum hypophosphite surface polymerization

Scientific objectives and payload configuration of the Chang'E-7 mission

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National Science Review 2024年第2期11卷 285-300页

作者： Chi Wang Yingzhuo Jia Changbin xue Yangting Lin Jianzhong Liu Xiaohui Fu Lin xu Yun Huang Yufen Zhao yigang xu Rui Gao Yong Wei Yuhua Tang Dengyun Yu Yongliao Zou State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences National Space Science Center Chinese Academy of Sciences institute of Geology and Geophysics Chinese Academy of Sciences institute of geochemistry Chinese Academy of Sciences Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Institute of Space SciencesShandong University institute of Drug Discovery Technology Ningbo University State Key Laboratory of Isotope geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Science and Engineering Sun Yat-sen University Lunar Exploration and Space Engineering Center china Aerospace Science and Technology Corporation

As the cornerstone mission of the fourth phase of the chinese Lunar Exploration Program, Chang'E-7(CE-7) was officially approved, and implementation started in 2022, including a main probe and a communication relay satellite. The main probe, consisting of an orbiter, a lander, a rover and a mini-flying probe, is scheduled to be launched in 2026. The lander will land on Shackleton crater's illuminated rim near the lunar south pole, along with the rover and mini-flying probe. The relay satellite(named Queqiao-2) will be launched in February 2024 as an independent mission to support relay communication during scientific exploration undertaken by Chang'E-4, the upcoming Chang'E-6 in 2024 and subsequent lunar *** CE-7 mission is mainly aimed at scientific and resource exploration of the lunar south pole. We present CE-7's scientific objectives, the scientific payloads configuration and the main functions for each scientific payload with its key technical specifications.

关键词： Chang’ E-7 scientific objectives scientific payloads

Tree wavelet approximations with applications

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Science china Mathematics 2005年第5期48卷 680-702页

作者： xu Yuesheng & ZOU Qingsong Department of Mathematics, Syracuse University, Syracuse, NY 13244, USA institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, Beijing 100080, china Department of Scientific Computing and Computer Science, Zhongshan University, guangzhou 510275, china 1. Department of Mathematics Syracuse University 13244 Syracuse NY USA 2. institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 3. Department of Scientific Computing and Computer Science Zhongshan University 510275 Guangzhou China

We construct a tree wavelet approximation by using a constructive greedy scheme (CGS). We define a function class which contains the functions whose piecewise polynomial approximations generated by the CGS have a prescribed global convergence rate and establish embedding properties of this class. We provide sufficient conditions on a tree index set and on bi-orthogonal wavelet bases which ensure optimal order of convergence for the wavelet approximations encoded on the tree index set using the bi-orthogonal wavelet bases. We then show that if we use the tree index set associated with the partition generated by the CGS to encode a wavelet approximation, it gives optimal order of convergence.

关键词： greedy algorithms tree wavelet approximations Besov spaces.

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 273-287页

作者： Wang Liankui, Zhang Shaoli, xu Wenxin, Liang Yuelong, Deng Gaoqiang, and Sha Liankunguangzhou Branch, institute of geochemistry, chinese academy of sciences, guangzhou, Guangdong Jiang M inxi guangzhou Branch Institute of Geochemistry

The traditional idea proposes that granites on the east and west coasts of the Pacific Ocean are different. According to field investigations of the geology of the western United States coupled with the authors' long-term studies on granites in South china, granites both in eastern china and in the western United States are similar.

关键词： Similarities Between Granites on the East and West Coasts of the Pacific Ocean Ruby West

Identification and analysis of shear waves recorded by three-component OBSs in northeastern South china Sea

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Progress in Natural Science:Materials International 2008年第2期18卷 181-188页

作者： Minghui Zhao ,xuelin Qiu,Shaohong Xia,Ping Wang,Kanyuan Xia,Huilong xu Key Laboratory of Marginal Sea Geology,South china Sea institute of Oceanology,chinese academy of sciences,guangzhou 510301,china Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Structure models associated with P-and S-wave velocities contain considerable amount of information on lithology and geophysical properties,which can be used to better understand the complexity of the deep crustal structure. However,records of converted shear waves are less due to the speciality of seismic survey at sea and the rigorous generated conditions. The study on shear waves has always been a weakness for studying the deep crustal structures of South china Sea (SCS). In this paper,eleven three-component OBSs were deployed along the Profile OBS-2001 in northeastern SCS. After the data processing of polarization and band-pass filter,converted S-wave phases were identified in the radical component records of nine OBSs. Taking the OBS7 as an example,identification and analysis of converted shear waves were presented and discussed in detail. A few phase groups,such as PwSc,PgSs,PnSc,PmS,and PwSn,were found coming from the deep crust or Moho interface by simple theoretical model calculation and ray-tracing simulation. The results not only provide the underlying basis for studies of S-wave velocity structure and Poisson’s ratio structure,but also reveal the relationship between crustal petrology and seismology,which will be of importance for making full use of S-wave information in the future.

关键词： Converted shear wave Deep crustal structure Three-component ocean bottom seismometer Northeastern South china Sea

Deep learning approaches to recover the plasma current density profile from the safety factor based on Grad–Shafranov solutions across multiple tokamaks

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Plasma Science and Technology 2024年第5期26卷 17-28页

作者：张瀚予周利娜刘钺强郝广周王硕杨旭苗雨田段萍陈龙 College of Science Dalian Maritime UniversityDalian 116026People’s Republic of China General Atomics San Diego 92186-5608United States of America Southwestern institute of Physics Chengdu 610041People’s Republic of China Chongqing Key Laboratory of Intelligent Perception and BlockChain Technology Chongqing Technology and Business UniversityChongqing 400067People’s Republic of China

Many magnetohydrodynamic stability analyses require generation of a set of equilibria with a fixed safety factor q-profile while varying other plasma parameters.A neural network(NN)-based approach is investigated that facilitates such a *** multilayer perceptron(MLP)-based NN and convolutional neural network(CNN)models are trained to map the q-profile to the plasma current density J-profile,and vice versa,while satisfying the Grad–Shafranov radial force balance *** the initial target models are trained,using a database of semianalytically constructed numerical equilibria,an initial CNN with one convolutional layer is found to perform better than an initial MLP *** particular,a trained initial CNN model can also predict the q-or J-profile for experimental tokamak *** performance of both initial target models is further improved by fine-tuning the training database,*** adding realistic experimental equilibria with Gaussian *** fine-tuned target models,referred to as fine-tuned MLP and fine-tuned CNN,well reproduce the target q-or J-profile across multiple tokamak *** an important application,these NN-based equilibrium profile convertors can be utilized to provide a good initial guess for iterative equilibrium solvers,where the desired input quantity is the safety factor instead of the plasma current density.

关键词： plasma equilibrium deep learning safety factor profile current density profile tokamak

Distribution and identification of the low-velocity layer in the northern South china Sea

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Progress in Natural Science:Materials International 2007年第5期17卷 591-600页

作者： Zhao Minghui, Qiu xuelin, xu Huilong, Shi Xiaobin, Wu Shimin , Ye Chunming and Xia Shaohong (Key Laboratory of Marginal Sea Geology, South china Sea institute of Oceanology, chinese academy of sciences, guangzhou 510301, china Earthquake Administration of Guangdong Province, guangzhou 510070, china) [a]Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China [b]Earthquake Administration of Guangdong Province Guangzhou China

The low-velocity layer (LVL), closely related with tectonic activities and dynamic settings, has always been a hot topic in the deep crustal structure studies. The deep seismic (OBS/OBH) and onshore-offshore experiments have been extensively implemented in the northern South china Sea (SCS) since the 1990s. Six seismic profiles were finished on the northern margin of SCS by domestic and international cooperations. The features of crustal structures were revealed and five velocity-inversion layers were discovered. Among them three LVLs with 3.0—3. 5 km·s-1 velocity are located in the sedimentary structure (2.0—6.0 km in depth and 2.0—4. 6 km in thickness) of the Yinggehai Basin and Pearl River Mouth Basin. They were identified by the reflective and refractive phases for their shallow depth. The other two LVLs with 5.5—6.0 km·s-1 velocity generally existed in the middle crust (7.0—18.0 km in depth) with an about 2.5—6.0 km thickness in the transitional crustal structure of the northeastern and northwestern SCS. They were detected by the refractive phase from their overlain and underlying layers. We explored the possible tectonic formation mechanisms combining with previously reported results, which provided evidence for the formation and evolution of SCS.

关键词： low-velocity layer deep crustal structure the northern South china Sea OBS/OBH and onshore-offshore seismic experiments.