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A Vanishing Theorem on a Class of Hartogs Domain

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Acta Mathematica Sinica,English Series 2023年第1期39卷 1-12页

作者： cheng chen zhong An WANG Li Shuang PAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China Science College Shijiazhuang UniversityHebei 050035P.R.China

In this paper,we consider the d-boundedness of the Bergman metric and a vanishing theorem of L2-cohomology on a class of Hartogs domain,whose base domain is the production of two irreducible bounded symmetric domains ... 详细信息

关键词： d-bounded vanishing theorem Bergman metric

河南省老湾金矿韧性剪切带特征及成矿机制探讨

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世界有色金属 2024年第16期 46-50页

作者：陈忠诚魏鸿喻艳丽陈霏霏徐刚广东万思邦科技有限公司河南省第三地质大队有限公司

老湾韧性剪切变质带是北秦岭古生代褶皱带与南秦岭印支褶皱带分界构造的一部分，呈NWW向展布，分为四个主应变带和两个岩片带。带内岩性分布以基性岩浆岩为主，兼有部分变质岩块体、酸性岩浆岩体和岩脉等。金矿化严格受韧性剪切变质带... 详细信息

老湾韧性剪切变质带是北秦岭古生代褶皱带与南秦岭印支褶皱带分界构造的一部分，呈NWW向展布，分为四个主应变带和两个岩片带。带内岩性分布以基性岩浆岩为主，兼有部分变质岩块体、酸性岩浆岩体和岩脉等。金矿化严格受韧性剪切变质带控制，主要集中分布在RF4强应变域中心及两侧的Ⅱ岩片区，辉绿一辉长岩为金的矿源层，后期老湾黑云母花岗岩对含金热流体起着成分改造和加强循环的作用。矿床成矿机制复杂，泥盆纪末，南北大陆发生碰撞，基性岩浆侵入，部分Au带入岩浆→印支期，发生强烈韧性剪切变形变质，Au元素活化运移，向强应变部位富集→燕山期，老湾花岗岩岩浆的热加入，Au进一步在剪切强应变带聚积成矿。

关键词：韧性剪切带特征成矿机制金矿老湾

Using a Tree Ring δ^(13)C Annual Series to Reconstruct Atmospheric CO_2 Concentration over the Past 300 Years

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Pedosphere 2006年第3期16卷 371-379页

作者： ZHAO Xing-Yun QIAN Jun-Long WANG Jian HE Qing-Yan WANG Zu-Liang chen cheng-zhong College of Geographical Science Nanjing Normal University Nanjing 210097 （China） Geography and Tourism Department Linyi Teachers＇ College Linyi 276005 Shandong （China） Lake Sediment and Environment Laboratory Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 （China） Administrative Bureau of Tianmu Mountain National Natural Protection District Lin＇an 311311 Zhejiang （China）

The annual series of δ13C were measured in tree rings of three Cryptomeria fortunei disks （OF-1, OF-2, and OF- 3） collected from West Tianmu Mountain, Zhejiang Province, China, according to cross-dating tree ring ages. There was no obvious decreasing trend of the δ13C annual time series of CF-2 before 1835. However, from 1835 to 1982 the three tree ring δ13C annual series exhibited similar decreasing trends that were significantly （P ≤ 0.001） correlated. The distribution characteristics of a scatter diagram between estimated δ13C series of CF-2 from modeling and the atmospheric CO2 concentration extracted from the Law Dome ice core from 1840 to 1978 were analyzed and a curvilinear regression equation for reconstructing atmospheric CO2 concentration was established with R2 = 0.98. Also, a test of independent samples indicated that between 1685 and 1839 the reconstructed atmospheric CO2 concentration .using the δ13C series of CF-2 had a close relationship with the Law Dome and Siple ice cores, with a standard deviation of 1.98. The general increasing trend of the reconstructed atmospheric CO2 concentration closely reflected the 10ng-term variation of atmospheric CO2 concentration recorded both before and after the Industrial Revolution. Between 1685 and 1840 the evaluated atmospheric CO2 concentration was stable, but after 1840 it exhibited a rapid increase. Given a longer δ13C annual time series of tree rings, it was feasible to rebuild a representative time series to describe the atmospheric CO2 concentration for an earlier period and for years that were not in the ice core record.

关键词： atmospheric CO2 concentration δ13C reconstruction time series tree ring

City Network Evolution Characteristics of Smart Industry: Evidence from Yangtze River Delta, China

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Chinese Geographical Science 2024年第5期34卷 829-848页

作者： SHEN Lizhen zhong Zhaocheng chen cheng ZHANG Shanqi ZHEN Feng School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Hefei Urban Planning&Design Institute Hefei 230041China

The dual-path model of industrial evolution and spatial progression has been widely acknowledged and incorporated into the strategic planning to promote the development of urban industries and regional ***,current research on inter-enter-prise city networks mainly focuses on the single sector of flows on all enterprise branches,such as product value chains and production factors,but neglects that of particular industry *** upon the new economic geography and city networks theory,this paper develops a methodological framework that focuses on the analysis of city network evolution characteristics of smart ***-larly,a conceptual model of smart industry enterprise-industry-city is proposed and then applied to a case study of smart industry in the Yangtze River Delta Region,*** enterprise supplier-customer data,a city network of smart industry is constructed and sub-sequently analyzed with the proposed *** indicate that the smart industry network in Yangtze River Delta Region exhibits a hierarchical structure and the expansion of the network presents a small-world network *** study not only makes a meth-odological contribution for revealing the industrial and spatial evolution path of the current smart industry,but also provides empirical support for the formulation of new economic development policies focused on smart industries,demonstrating the role of city clusters as carriers of regional synergistic development.

关键词： smart industry city networks social network analysis methodological framework Yangtze River Delta,China

Triple reverse order law for the Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG Hua zhong cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation ***,the Drazin invertibility of sum is also obtained for two bounded linear operators and... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Two-dimensional layered In_(2)P_(3)S_(9): A novel superior anode material for sodium-ion batteries

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Journal of Energy Chemistry 2024年第3期90卷 294-304,I0008页

作者： Longsheng zhong Hongneng chen Yanzhe Sheng Yiting Sun Yanhe Xiao Baochang cheng Shuijin Lei School of Physics and Materials Science Nanchang UniversityNanchang 330031JiangxiChina

Developing reliable and efficient anode materials is essential for the successfully practical application of sodium-ion ***,employing a straightforward and rapid chemical vapor deposition technique,two-dimensional layered ternary indium phosphorus sulfide(In_(2)P_(3)S_(9)) nanosheets are *** layered structure and ternary composition of the In_(2)P_(3)S_(9) electrode result in impressive electrochemical performance,including a high reversible capacity of 704 mA h g^(-1) at 0.1 A g^(-1),an outstanding rate capability with 425 mA h g^(-1) at 5 A g^(-1),and an exceptional cycling stability with a capacity retention of88% after 350 cycles at 1 A g^(-1).Furthermore,sodium-ion full cell also affords a high capacity of 308 and114 mA h g^(-1) at 0.1 and 5 A g^(-1).Ex-situ X-ray diffraction and ex-situ high-resolution transmission electron microscopy tests are conducted to investigate the underlying Na-storage mechanism of In_(2)P_(3)S_(9).The results reveal that during the first cycle,the P-S bond is broken to form the elemental P and In_(2)S_(3),collectively contributing to a remarkably high reversible specific *** excellent electrochemical energy storage results corroborate the practical application potential of In_(2)P_(3)S_(9) for sodium-ion batteries.

关键词： Metal thiophosphate In_(2)P_(3)S_(9) Anode material Sodium-ion battery Full cell

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

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Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： Xiao-Gu zhong Jian-cheng Wang Yong-Yun chen Xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations

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Journal of Energy Chemistry 2024年第6期93卷 299-305,I0008页

作者： Legeng Yu Nan Yao Yu-chen Gao zhong-Heng Fu Bo Jiang Ruiping Li cheng Tang Xiang chen Tsinghua Center for Green Chemical Engineering Electrification(CCEE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos 017010Inner Mongoli1China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan University2066 Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea

Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium ***,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very ***,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an *** interface model was developed,incorporating the electrode potential and atom *** a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic ***,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,*** preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+*** CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.

关键词： Lithium batteries Graphite N-doping Electric double layer Molecular dynamics Constant potential method Electrode potential

Microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents during heat treatments

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Rare Metals 2024年第4期43卷 1786-1792页

作者： Yuan-Feng Xie Xing-cheng Xie zhong-Wu Li Rui-Jun Cao zhong-Kun Lin Qing Li chen-Guang Lin Powder Metallurgy and Special Materials Research Department General Research Institute for Nonferrous MetalsBeijing100088China

The effects of cryogenic treatment(CT)and tempering-cryogenic treatment(TCT)on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were *** binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were *** results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles W_(x)Co_(y)C_(z) in the binder during the heat treatments of CT and *** the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarsegrained cemented carbide Carbon content Nanoparticlereinforced binder