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MC-ICP-MS 测定岩石标准物质的钒同位素组成

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岩矿测试 2025年第1期44卷 63-74页

作者：徐丽怡于慧敏丁昕黄方中国科学技术大学地球和空间科学学院岩石圈演化与环境演变全国重点实验室安徽合肥230026 中国科学院比较行星学卓越创新中心中国科学技术大学安徽合肥230026

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(US... 详细信息

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(USGS)的标准物质面临着库存不足等问题,本文采用多接收电感耦合等离子体质谱仪(MC-ICP-MS)测定了一系列国际地质标准物质和国家地质标准物质的钒同位素组成,δ51V值的测试精度优于0.08‰。本文选取的标准物质主要来自日本地质调查局(GSJ)和中国地质科学院地球物理地球化学勘查研究所(IGGE),包括一个安山岩(JA-1),三个玄武岩(JB-3、JB-1b和GBW07105),一个辉长岩(JGb-1),一个辉绿岩(GBW07123)以及一个土壤(GBW07454),钒含量范围为77~635μg/g,涵盖了目前大部分火成岩和部分土壤等天然样品含量的范围。这些标准物质除了土壤GBW07454,其他标准物质的钒同位素组成未曾被报道。经测量表明,辉长岩标准物质JGb-1具有最高δ51V值,为−1.05‰±0.08‰,安山岩标准物质JA-1具有最低δ51V值,为−0.34‰±0.06‰,其余标准物质的δ51V值变化范围为−0.72‰~−0.81‰,均落在MORB范围内。本文对这些标准物质钒同位素组成的报道,丰富了钒同位素研究的标准物质数据库,有助于未来在更多领域开展钒同位素研究。

关键词：钒同位素火成岩 MC-ICP-MS 标准物质高精度分析方法

Recent developments in topological string theory

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Science China(Physics,Mechanics & Astronomy) 2019年第9期62卷 1-15页

作者： Min-xin huang Interdisciplinary Center for Theoretical Study School of Physical SciencesUniversity of Science and Technology of China

This review summarizes the recent developments in topological string theory from the author’s perspective, mostly focusing on aspects of research in which the author is involved. After a brief overview of the theory, we discuss two aspects of these developments. First, we discuss the computational progress in the topological string partition functions on a class of elliptic Calabi-Yau manifolds. We propose to use Jacobi forms as an ansatz for the partition function. For non-compact models, the techniques often provide complete solutions, while for compact models, though it is still not completely solvable, we compute to higher genus than previous works. Second, we explore a remarkable connection of refined topological strings on a class of non-compact toric Calabi-Yau threefolds with non-perturbative effects in quantum-mechanical systems. The connections provide rarely available exact quantization conditions for quantum systems and new insights on non-perturbative formulations of topological string theory.

关键词： topological string theory Calabi-Yau manifolds non-perturbative effects

P-Laplace Equation for the Grushin Type Operator

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Acta Mathematica Sinica,english Series 2023年第5期39卷 923-938页

作者： Ji Zheng huang xin xin YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876P.R.China

Let Gλ,λ>0,be a Grushin type operator on Rn×*** this paper,we will first establish existence and uniqueness for the p-Laplace equation for Gλ,then we prove the regularity of *** order to prove our results,we will ... 详细信息

关键词： solutions. inequality uniqueness

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Macroeconomic Momentum

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China Today 2025年第1期74卷 48-49页

作者： huang YIPING National School of Development at Peking University

As China loses some old advantages in its new development phase,it can gain more by changing its growth *** to a joint study by experts from Chinese and American think tanks,there are three prominent changes in China... 详细信息

关键词： tank think economy

A nonlinear constitutive model for magnetostrictive materials

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Acta Mechanica Sinica 2005年第3期21卷 278-285页

作者： xin'en Liu Xiaojing Zheng Department of Mechanics Lanzhou University Lanzhou 730000 China

A general nonlinear constitutive model is proposed for magnetostrictive materials, based on the important physical fact that a nonlinear part of the elastic strain produced by a pre-stress is related to the magnetic domain rotation or movement and is responsible for the change of the maximum magnetostrictive strain with the pre-stress. To avoid the complicity of determining the tensor function describing the nonlinear elastic strain part, this paper proposes a simplified model by means of linearizing the nonlinear function. For the convenience of engineering applications, the expressions of the 3-D （bulk）, 2-D （film） and 1-D （rod） models are, respectively, given for an isotropic material and their applicable ranges are also discussed. By comparison with the experimental data of a Terfenol-D rod, it is found that the proposed model can accurately predict the magnetostrictive strain curves in low, moderate and high magnetic field regions for various compressive pre-stress levels. The numerical simulation further illustrates that, for either magnetostrictive rods or thin films, the proposed model can effectively describe the effects of the pre-stress or residual stress on the magnetization and magnetostrictive strain curves, while none of the known models can capture all of them. Therefore, the proposed model enjoys higher precision and wider applicability than the previous models, especially in the region of the high field.

关键词： Magnetostrictive materials Constitutive relations Terfenol-D rods Magnetostrictive thin films Microactuators

Livability assessment of 101,630 communities in China's major cities: A remote sensing perspective

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Science China Earth Sciences 2022年第6期65卷 1073-1087页

作者： xin huang Yue LIU School of Remote Sensing and Information engineering Wuhan UniversityWuhan 430079China State Key Laboratory of Information engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

Some of China's major cities have entered the middle and late stages of urbanization, and the development focus of these cities has gradually shifted from outward expansion to inward renewal. The community, as the basic unit of a city, is undoubtedly the main object of urban renewal. In order to efficiently and effectively address the problems in current community construction, it is necessary to conduct a large-scale in-depth assessment of the community livability, which can directly imply the satisfaction of residents with their quality of life. This study achieved the first comprehensive livability assessment at the individual community scale for 42 major cities of China from the perspective of remotely sensed and crowd-sourced geographic information. Specifically, we produced abundant fine-grained datasets for 42 cities, including high-resolution land cover maps interpreted from Ziyuan-3 satellites(ZY-3, 2.1 m), building height, point-of-interest, and boundaries of 101,630 *** designed in our proposed framework, the community livability was evaluated by 5 level-1 indicators, 27 level-2 indicators and an integrated community livability index(CLI). A number of interesting findings were obtained from this assessment:(1)According to the expert questionnaires, living comfort was considered as the most important livability factor for residents with the highest weight, while the building environment was rated the least. The negative factors(e.g., the factories around the community) impacted more on livability than the positive ones.(2) Most communities in major Chinese cities were characterized by dense buildings and sparse green spaces.(3) In these cities, community security construction was severely insufficient,particularly in less developed regions.(4) Imbalanced community livability development was prevalent across cities, and simultaneously, the CLI distribution within cities also exhibited significant spatial aggregation and heterogeneity. This resear

关键词： Community Livability Living comfort Building environment Security Remote sensing

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Learning-Based Switched Reliable Control of Cyber-Physical Systems With Intermittent Communication Faults

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 711-724页

作者： xin huang Jiuxiang Dong College of Information Science and engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Synthetical Automation of Process Industries Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern UniversityShenyang 110819China IEEE

This study deals with reliable control problems in data-driven cyber-physical systems(CPSs) with intermittent communication faults, where the faults may be caused by bad or broken communication devices and/or cyber attackers. To solve them, a watermark-based anomaly detector is proposed, where the faults are divided to be either detectable or ***, the fault's intermittent characteristic is described by the average dwell-time(ADT)-like concept, and then the reliable control issues, under the undetectable faults to the detector, are converted into stabilization issues of switched systems. Furthermore,based on the identifier-critic-structure learning algorithm, a datadriven switched controller with a prescribed-performance-based switching law is proposed, and by the ADT approach, a tolerated fault set is given. Additionally, it is shown that the presented switching laws can improve the system performance degradation in asynchronous intervals, where the degradation is caused by the fault-maker-triggered switching rule, which is unknown for CPS operators. Finally, an illustrative example validates the proposed method.

关键词： Adaptive dynamic programming(ADP) communication fault cyber-physical systems(CPSs) data-driven control reliable control

Lsyn-Esyn,p-δrelation in active galactic nucleus jets and implication for the physical origin of the Lp-Ep,z-Γ_0 relation of gamma-ray bursts

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Research in Astronomy and Astrophysics 2020年第9期20卷 201-209页

作者： Xiao-Li huang en-Wei Liang School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

High energy photon radiations of gamma-ray bursts(GRBs)and active galactic nuclei(AGNs)are dominated by their jet *** examine whether the synchrotron radiations of jets in BL Lacs,flat spectrum radio quasars(FSRQs),and Narrow Line Seyfert 1 galaxies(NLS1s)follow the relation between the prompt gamma-ray emission and the initial Lorentz factor(Γ0)of *** is shown that the AGN sample does not agree with the Lp-Ep,z-Γ0 relation of *** addition,we obtain a tight relation of Lsyn∝Е0.45±0.15δ3.50±0.25 syn,p for FSRQs and NLS1 galaxies,where Lsyn is the luminosity at peak photon energy Esyn,p of the synchrotron *** relation is different from the Lp-Ep,z-Γ0 relation of GRB *** dependence of Lsyn toδis consistent with the expectation of the Doppler boosting effect for the FSRQs and NLS1 galaxies,but it is not for *** argue thatΓ0 may be a representative of the kinetic power of the radiating region and the tight Lp-Ep,z-Γ0 relation is shaped by the radiation physics and the jet power together.

关键词： gamma-ray burst:general quasars:general BL Lacertae objects:general galaxies:Seyfert stars:jets radiation mechanisms:non-thermal

超碱NLi_(4)团簇修饰DHQ石墨烯的储氢性能研究

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原子与分子物理学报 2025年第5期42卷 95-101页

作者：戴小乐王允辉黄欣南京邮电大学电子与光学工程学院柔性电子(未来技术)学院南京210023 南京邮电大学理学院南京210023

基于第一性原理计算,系统研究了超碱NLi_(4)团簇修饰在DHQ石墨烯表面上的几何结构及吸附能等性质,并深入探索了其储氢性能.研究结果表明:超碱NLi_(4)团簇可以稳定均匀地吸附在DHQ石墨烯表面,Li原子与N原子的强结合能有效避免了Li原子发... 详细信息

基于第一性原理计算,系统研究了超碱NLi_(4)团簇修饰在DHQ石墨烯表面上的几何结构及吸附能等性质,并深入探索了其储氢性能.研究结果表明:超碱NLi_(4)团簇可以稳定均匀地吸附在DHQ石墨烯表面,Li原子与N原子的强结合能有效避免了Li原子发生团聚.每个NLi_(4)团簇周围最多可吸附11个氢气分子,平均吸附能为0.20 eV,最大储氢容量为12.05 wt%,达到美国能源部制定的2025年储氢目标5.5 wt%.最后,基于相对能量计算,发现当压强大于84 bar时,该储氢体系可以在室温下稳定存在.以上结果表明经超碱NLi_(4)团簇修饰的DHQ石墨烯是一种有潜力的储氢材料.

关键词：多孔材料储氢超碱NLi_(4)团簇 DHQ石墨烯第一性原理计算