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Evaluation of 3D crustal seismic velocity models in southwest china:Model performance,limitation,and prospects

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Science china Earth sciences 2024年第2期67卷 604-619页

作者： Xin WANG Ling chen Qi-fu chen Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest china is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2.2. Yunnan Yangbi MS_(6.4) earthquake sequence and the 2.2. Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest china Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental china Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(2.Hz)waveforms,indicating that the 3D models adequately resolve overall large-scale subsurface ***,the 3D synthetics show discrepancies in higher frequencies(0.05–0.3 Hz)and the performance of the 3D velocity models varies from region to region,suggesting that smaller scale heterogeneities are not well *** shallow velocity structures(full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest china Seismic tomography models Shallow Structures Waveform simulation Model evaluation

Mathematics of multi-agent learning systems at the interface of game theory and artificial intelligence

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Science china(Information sciences) 2024年第6期67卷 445-447页

作者： Long WANG Feng fu Xingru chen Center for Systems and Control College of EngineeringPeking University Center for Multi-Agent Research Institute for Artificial IntelligencePeking University Department of Mathematics Dartmouth College Department of Biomedical Data Science Geisel School of Medicine at Dartmouth School of Science Beijing University of Posts and Telecommunications

Evolutionary game theory (EGT) and artificial intelligence(AI) are two fields that,at first glance,might seem distinct,but they have notable connections and *** former focuses on the evolution of behaviors (or strategies)in a population,where individuals interact with others and update their strategies based on imitation (or social learning).

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Atmospheric Deposition-Carried Pb, Zn, and Cd from a Zinc Smelter and Their Effect on Soil Microorganisms

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Pedosphere 2009年第4期19卷 422-433页

作者： YANG Yuan-Gen2. JIN Zhi-Sheng, BI Xiang-Yang, LI Fei-Li, SUN Li, LIU Jie and fu Zhi-You institute of {2., chinese Academy of sciences, guiyang 550002.(china) institute of geochemistry Chinese Academy of Sciences Guiyang 550002 (China)

Dust emissions from smelters, as a major contributor to heavy metal contamination in soils, could severely influence soil quality. Downwind surface soils within 1.5 km of a zinc smelter, which was active for 10 years but ceased in 2.00, in Magu Town, Cuizhou Province, china were selected to examine Pb, Zn, and Cd concentrations and their fractionation along a distance gradient from a zinc smelter, and to study the possible effects of Pb, Zn, and Cd accumulation on soil microorganisms by comparing with a reference soil located at a downwind distance of 10 km from the zinc smelter. Soils within 1.5 km of the zinc smelter accumulated high levels of heavy metals Zn （508 mg kg^-1）, Pb （95.6 mg kg^-1）, and Cd （5.98 mg kg^-1） with low ratios of Zn/Cd （59.1-115） and Pb/Cd （12.4-2..4）. Composite pollution indices （CPIs） of surface soils （2.52.15.2. were 3 to 13 times higher than the reference soils. In metal accumulated soils, exchangeable plus carbonate-bound fractions accounted for more than 10% of the total Zn, Pb, and Cd. The saturation degree of metals （SDM） in soils within 1.5 km of the smelter （averaging 1.2.） was six times higher than that of the reference soils （0.2.9）. A smaller soil microbial biomass was found more frequently in metal accumulated soils （85.1-438 μg C g^-1） than in reference soils （497 μg C g^-1）, and a negative correlation （P 〈 0.01） of soil microbial biomass carbon to organic carbon ratio （Cmic/Corg） with SDM was observed. Microbial consumption of carbon sources was more rapid in contaminated soils than in reference soils, and a shift in the substrate utilization pattern was apparent and was negatively correlated with SDM （R = -0.773, P 〈 0.01）. Consequently, dust deposited Pb, Zn, and Cd in soils from zinc smelting were readily mobilized, and were detrimental to soil quality mainly in respect of microbial biomass .

关键词： composite pollution index heavy metals microbial biomass saturation degree of metals sequential extrac- tion

Both gain-and loss-of-function variants of KCNA1 are associated with paroxysmal kinesigenic dyskinesia

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Journal of Genetics and Genomics 2024年第8期51卷 801-810页

作者： Wan-Bing Sun Jing-Xin fu Yu-Lan chen Hong-fu Li Zhi-Ying Wu Dian-fu chen Department of Medical Genetics and Center for Rare Diseases and Department of Neurologyand Zhejiang Key Laboratory of Rare Diseases for Precision Medicine and Clinical Translation in Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Nanhu Brain-computer Interface institute HangzhouZhejiang 314050China MOE Frontier Science Center for Brain Science and Brain-machine Integration School of Brain Science and Brain MedicineZhejiang UniversityHangzhouZhejiang 310012China

KCNA1 is the coding gene for Kv1.1 voltage-gated potassium-channelα*** variants of KCNA1 have been reported to manifest as paroxysmal kinesigenic dyskinesia(PKD),but the correlation between them remains unclear due to the phenotypic complexity of KCNA1 variants as well as the rarity of PKD *** the whole exome sequencing followed by Sanger sequencing,we screen for potential pathogenic KCNA1 variants in patients clinically diagnosed with paroxysmal movement disorders and identify three previously unreported missense variants of KCNA1 in three unrelated chinese *** proband of one family(c.496G>A,p.A166T)manifests as episodic ataxia type 1,and the other two(c.877G>A,p.V2.3I and c.1112.>A,p.T371A)manifest as *** pathogenicity of these variants is confirmed by functional studies,suggesting that p.A166T and p.T371A cause a loss-of-function of the channel,while p.V2.3I leads to a gain-of-function with the property of voltage-dependent gating and activation kinetic *** reviewing the locations of PKD-manifested KCNA1 variants in Kv1.1 protein,we find that these variants tend to cluster around the pore domain,which is similar to ***,our study strengthens the correlation between KCNA1 variants and PKD and provides more information on genotype–phenotype correlations of KCNA1 channelopathy.

关键词： Paroxysmal kinesigenic dyskinesia KCNA1 Loss-of-function Gain-of-function Channelopathy Episodicataxiatype1

Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils

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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun Zhu fu-San chen china Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of chinese Academy of sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2.,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Evolution of the upper earth crust in the southwest area of Yangtze terrain and its influence on the formation of Carlin-type Au ore deposits

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chinese Science Bulletin 1999年第S2期44卷 220-221页

作者： chen Xiaozhong and LI Chaoyang Open Laboratory Laboratory of Ore geochemistry, {2. of geochemistry, chinese Academy of sciences, guiyang 550002. china Open Laboratory Laboratory of Ore geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

1 Outline of the Yangtze terrain THE northwestern area of Sichuan and the joined area of Yunnan, Guizhou and Guangxi are the two majorfields where lots of Carlin-type Au ore deposits are located. Both of them belong to the western area ofYangtze terrain. The evolution of Yangtze terrain affected profoundly the geological evolution in these areas. Many epithermal ore deposits, such as Carlin-type gold, lead, zinc, mercury, stibium and arsenic,occur in the these areas, due to the evolution of crust in Yangtze terrain. The foundation of Yangtze terrain shows a structure of three stories, mainly composed of the Proterozoic clastic rocks and carbonic rocks that were involved in low-middle grade metamorphose. The meaningof the Yangtze terrain changed according to several geological times, which can be said that the activity ofYangtze terrain changed in the past. The Yangtze terrain undertook several processes of landmass hyper-

关键词： Yangtze terrain extending basin Carlin-type Au ore deposit.

Effects of cement-enhanced soil on the ultimate lateral resistance of composite pile in clayey soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 183-191页

作者： Zhijun Yang Kexin chen Xudong fu Zhiyan Zou School of Civil Engineering Wuhan UniversityWuhan430000China Changjiang Design Group Co. Ltd.Wuhan430000China institute of Geotechnical Engineering College of Civil Engineering and ArchitectureMOE Key Laboratory of Soft Soils and Geoenvironmental EngineeringZhejiang UniversityHangzhou310000China

The composite pile consisting of core-pile and surrounding cement-enhanced soil is a promising pile foundation in recent ***,how and to what extent the cement-enhanced soil influences the ultimate lateral resistance has not been fully *** this paper,the ultimate lateral resistance of the composite pile was studied by finite element limit analysis(FELA)and theoretical upper-bound *** results of FELA and theoretical analysis revealed three failure modes of laterally loaded composite *** effects of the enhanced soil thickness,strength,and pile-enhanced soil interface characteristics on the ultimate lateral resistance were *** results show that increasing the enhanced soil thickness leads to a significant improvement on ultimate lateral resistance factor(N P),and there is a critical thickness beyond which the thickness no longer affects the N *** the enhanced soil strength induced 6.2.-2.2.6%increase of N ***,no noticeable impact was detected when the enhanced soil strength was eight times higher than that of the natural *** maximum increment of N P is only 30.5%caused by the increase of interface adhesion factor(a).An empirical model was developed to calculate the N P of the composite pile,and the results show excellent agreement with the analytical results.

关键词： Composite pile Ultimate soil resistance Finite element limit analysis(FELA) Plasticity theory Failure mode

Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： fu-cheng Deng fu-Lin Gui Bai-Tao Fan Lei Wen Sheng-Hong chen Ning Gong Yun-chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2.Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

High resolution environmental records in recent sediments of Erhai Lake, Yunnan Province

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chinese Science Bulletin 1999年第S2期44卷 88-90页

作者： chen Jingan, WAN Guojiang and TANG Degui State Key Laboratory of Environmental geochemistry, {2. of geochemistry, chinese Academy of sciences, guiyang 550002. china State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

IN the past half a century, the global paleoclimate has been successfully reconstructed by natural recordssuch as ice core, loess and deep-sea sediments. However, these works mostly focused on long-timescale climatic changes. Along with the appearance of modern environmental problems including globalwarming, people are increasingly concerned about short-term climatic variations (annual to century scale)within the historical period. Therefore, it is an urgent and significant task for scientists to obtain continuous and high resolution natural records so as to reconstruct recent climatic changes truly and predict theclimate in the near future. As a main lodging of surface substances, the plateau-lake sediment continuously records the information of regional climate and environment with annual to decade resolution. Undoubtedly it is one

关键词： lake sediments high resolution climatic changes Erhai Lake.