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Post-rifting magmatism at the northern margin of the South China Sea:Evidenced by an ocean bottom seismometer experiment

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Earthquake Science 2025年第1期38卷 1-16页

作者： Lu Zhang Chen cai Rui Gao School of Earth Sciences and Engineering Sun Yat-sen UniversityGuangzhou 510275China School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Guangdong Provincial Key Lab of Geodynamics and Geohazards Guangzhou 510275China Guangdong Deep Earth Exploration and Geological Process Technology Research Center Guangzhou 510275China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

Magmatism at continental margins is of great significance in understanding the continental *** present a twodimensional P-wave velocity model derived from an ocean bottom seismometer experiment,conducted across the middle northern continental margin of the South China Sea(SCS).The detailed velocity structures reveal significant heterogeneities extending from the continental shelf to the continent-ocean transition *** crust exhibits its greatest thickness below the continental shelf,measuring~23 km and gradually thins to~13 km at the distal ***,a narrow and distinct continent-ocean transition with only 40-km width is *** also observe a high-velocity layer within the transition zone,reaching thickness of up to 4 km,characterized by P-wave velocities ranging from 7.0 km/s to 7.6 km/s in the lower *** on the syn-rift melt generation using decompression melting model,we ascertain that syn-rift magmatism cannot fully account for the observed thick high-velocity *** integrating findings from previous geophysical and geochemical studies presenting extensive volcanic edifice on the seafloor at the northern margin,as well as ocean-island-basalt-type magmaticsamples in the SCS area,we propose that post-rifting magmatism associated with the Hainan Plume may have influenced theformation of the high-velocity lower crust within the transition zone and the northern margin of the SCS can thus be recognizedas magma-poor type margin.

关键词： South China Sea continental margin seismic refraction post-rift magmatism

Supply Chain Disruption and Import Strategy:Evidence from the Great East Japan Earthquake

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China & World Economy 2025年第1期33卷 132-161页

作者： Fan Lu Zhicong Li Xinrong cai School of Public Finance and Taxation Central University of Finance and EconomicsChina School of Finance and Taxation Zhongnan University of Economics and LawChina

Global supply chain networks foster collaboration but accelerate cross-border risk *** study investigates the effect of the 2011 East Japan earthquake on Chinese firms'import *** findings reveal that the disruption led to a shift toward supply chain concentration,with firms reducing the diversification of import *** was a slight increase in the number of countries from which firms sourced imports but import shares became more concentrated,reflecting a reliance on fewer,centralized *** affected by the earthquake prioritized long-term partnerships and sought suppliers in regions with lower natural disaster risks,aiming to mitigate supply chain vulnerabilities and reduce switching *** findings also show that state-owned enterprises,private firms,and research and development-intensive firms were more inclined to centralize their import *** suggests that these firms,leveraging their larger scale,substantial resources,and robust risk management strategies,favored a more concentrated sourcing approach in order to better control their supply chains and ensure stability in the face of global disruptions.

关键词： firm behavior import strategy natural disaster supply chain

Auxiliary-field Monte Carlo method for frustrated spin systems

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Chinese Physics B 2025年第2期34卷 118-122页

作者： Ning cai Yuan Gao Wei Li Yang Qi State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China School of Physics Beihang UniversityBeijing 100191China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

We extend a semiclassical numerical method, bosonic auxiliary-field Monte Carlo, to quantum spin systems. This method breaks the lattice into clusters, solves each cluster precisely and couples them with classical auxiliary fields through classical Monte Carlo simulation. We test the method with antiferromagnetic spin models in one-dimensional chains, square lattices and triangular lattices, and obtain reasonable results at finite temperatures. This algorithm builds a bridge between classical Monte Carlo method and quantum methods. The algorithm can be improved with either progress in classical Monte Carlo sampling or the development of quantum solvers, and can also be further applied to systems with different lattices or interactions.

关键词： Monte Carlo quantum many-body system frustrated magnets

应用MIPAS/ENVISAT卫星遥感资料研究平流层爆发性增温过程中大气化学成分变化特征

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遥感技术与应用 2008年第4期23卷 389-393,I0005页

作者：王海平刘毅蔡兆男中国科学院大气物理研究所北京100029

2002年12月～2003年1月北半球高纬地区平流层发生了一次爆发性增温过程（SSW），使该地区的动力、热力场和大气化学成分的分布发生剧烈变化。选取了搭栽在欧洲环境探测卫星EN—VISAT上的对地遥感观测仪器麦克耳逊干涉被动大气探测仪（MI... 详细信息

2002年12月～2003年1月北半球高纬地区平流层发生了一次爆发性增温过程（SSW），使该地区的动力、热力场和大气化学成分的分布发生剧烈变化。选取了搭栽在欧洲环境探测卫星EN—VISAT上的对地遥感观测仪器麦克耳逊干涉被动大气探测仪（MIPAS）的观测数据，首先利用臭氧探空资料和再分析气象资料对MIPAS观测的臭氧和温度廓线资料进行了对比验证；其次使用该资料对此次SSW过程进行了研究。对比结果显示，MIPAS资料与NCEP和臭氧探空资料都有较好的一致性。在这次平流层爆发性增温事件中，增温过程随时间向下传播影响到平流层下层。N2O和CH4的水平和垂直浓度分布与位涡反映的极涡始终都有很好的一致性。O3和H2O的浓度分布也受到极涡的限制，O3体积混合比随增温而增大，有极涡外的O3进入极涡。NO2并未受到极涡分布的严格限制，在极区维持低浓度区。HNO3浓度场在极区显示为极大值，但并不与极涡对应。

关键词： ENVISAT MIPAS 大气化学成分平流层爆发性增温

Statistical Research on Megahertz-peaked Spectra Pulsars

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Research in Astronomy and Astrophysics 2025年第1期25卷 116-134页

作者： Hong-Bing cai Li Chen Shi-Dang Li Kai Wang Hang Liu JSNU SPBPU Institute of Engineering & SINO RUSSIAN Institute Jiangsu Normal University School of Physics and Electronic Engineering Jiangsu Normal University

Megahertz-peaked spectra(MPS) pulsars are referred as cases whose radio spectra turn over around 100 MHz. We identified 53 MPS pulsars based on the spectral data from the literature, and statistically analyzed the spatial location distribution, the magnetic field-period distribution, peak frequencies, spectral indices, and dispersion measures of these MPS pulsars. We found that there is a strong positive correlation between the dispersion measures and the peak frequencies of MPS pulsars, and negative correlations of the dispersion measures with spectral indices and the ages are also found. Such correlations suggest that the interstellar medium is an important factor that affects observational properties of MPS pulsars.

关键词： (stars:) pulsars: general ISM: general radio continuum: general

A color-changing carbon dots/hydrogel composite for human motion sensing and sweat pH detection

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nano Research 2025年第2期18卷 1-10页

作者： Junje cai Huajiang Hu Jiurong Li Junfei Liao Xiao Gong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

Carbon dots(CDs)are a type of fluorescent nanomaterial that have gained significant attention due to their simple synthesis method and excellent optical *** unique structure of CDs also allows for effective luminescence *** have been reported to be pH-sensitive in many ***,most of these reports are based on the variation of the luminescence intensity of CDs with pH *** are few reports on exploring the linearly tunable variation of the luminescence wavelength with pH ***,we synthesized novel pH-sensitive CDs using a simple solvothermal *** synthesized CDs can change their luminescence emission wavelength by simply adjusting the pH of the *** change in emission wavelength may be due to the alteration in the surface state of the CDs caused by the pH *** luminous color change of the CDs allows for visual detection of the pH of the *** addition,a color-changing hydrogel composite for pH sensing was designed based on the pH sensitivity of the *** CDs@hydrogel has conductive properties that enable it to be used for motion sensing and sweat pH detection.

关键词： carbon dots multicolor pH-sensitive hydrogel motion sensing

Convergence of a New Bregman Projection Method with a Self-adaptive Stepsize for Solving Monotone Inclusion Problems and Variational Inequality Problems in Reflexive Banach Spaces

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数学进展 2025年第1期54卷 141-163页

作者： CHEN Lulu cai Gang School of Mathematical Sciences Chongqing Normal UniversityChongqing401331P.R.China

The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach *** strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the *** numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.

关键词： Bregman distance variational inequality monotone inclusion maximal operator reflexive Banach space

Analysis of the redox environment and genesis of surface sediment in the northeast Indian Ocean at the Ninety-East Ridge

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Journal of Oceanology and Limnology 2025年第1期43卷 57-72页

作者： Zhourong cai Qianru HUANG Zhengxin YIN Xin SUI Sibo LÜ Meng TANG Juan PENG School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering Zhuhai 519082China South China Sea Marine Survey Center Ministry of Natural ResourcesGuangzhou 510275China Key Laboratory of Marine Environmental Survey Technology and Application Ministry of Natural ResourcesGuangzhou 510275China

The Ninety-East Ridge(NER)is located in the semioceanic to oceanic region of the southern Bengal Fan in the Northeast Indian *** sedimentary environment,ocean currents,and scientific issues related to climate change have always been the focus of *** well understand the sedimentary environment of the sea area,we studied the modern sedimentary environment of the NER by analyzing the redox-sensitive trace elements(RSEs)and biomarkers in the surface sediments of the northern region and both sides of the NER and the mechanism of their *** ratios of Mo/U(average 2.22),(Cu+Mo)/Zn(average 1.51),and the results ofδCe<1 of the sediment samples,all indicate the reduction of the sedimentary *** addition,the ratio of pristane(Pr)to phytane(Ph),C30diahopane to C30 hopane,and diasterane to sterane were low in all samples,on average of 1.03,0.9,and 0.33,*** analysis of RSE and biomarker data revealed that the sedimentary environment on seabed of the NER is generally a rare low-oxygen reduction *** the analysis of sediment characteristics,material sources,and ocean currents,we preliminarily constructed a genetic model for the low-oxygen reducing environment of surface sediments in the *** believe that the low-oxygen reduction environment of surface sediment in the NER could be influenced by multiple factors,such as terrestrial input of materials,productivity at sea surface,and sediment particle size.

关键词： Ninety-East Ridge(NER) surface sediment sedimentary environment redox-sensitive trace elements(RSEs) biomarker

Taming of trinitromethyl-oxadiazole to access high density and high oxygen balance via a dual modulation strategy

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Defence Technology(防务技术) 2025年第1期43卷 142-149页

作者： Jinya Zhang Teng Fei Jingwei Meng Jinxiong cai Lei Zhang Siping Pang Chunlin He School of Materials Science&Engineering Beijing Institute of TechnologyBeijing 100081China Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China hongqing Innovation Center Beijing Institute of TechnologyChongqing 401120China

Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense *** this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive *** this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic ***,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),***,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and *** work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials.

关键词： Energetic materials High oxygen balance High density Dual modulation Trinitromethyl group