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我与美国主播翠西·里根“辩论”前后

全球传媒学刊 2019年第3期6卷 113-119页

作者：刘欣中国国际电视台(CGTN)

2019年5月CGTN主播刘欣在美国福克斯财经频道《翠西·里根黄金时间》上的露面是一次前所未有的国际媒体事件,为刘欣个人以及中国国际电视台带来了创纪录的海内外关注。整个事件是被什么引发的?幕后的决策过程怎样?刘欣进行了怎样的准备... 详细信息

2019年5月CGTN主播刘欣在美国福克斯财经频道《翠西·里根黄金时间》上的露面是一次前所未有的国际媒体事件,为刘欣个人以及中国国际电视台带来了创纪录的海内外关注。整个事件是被什么引发的?幕后的决策过程怎样?刘欣进行了怎样的准备?她自己最大的关切是什么,她又是如何回应的?在本篇文章中,刘欣回忆了一些关键时刻,帮助人们从内部窥探这一被认为中国数十年来争取国际话语权努力的里程碑事件。刘欣认为该事件的效果基于她20多年对外沟通的实践。不过一个关键的'策略'是做真实的自己。她相信诚意是她的强项,哪怕这意味着需要直面缺点。从外界的反响来看,刘欣的确给人留下了真诚的印象。对于努力引起关注和重视的中国发声者来说,这可以是一条值得借鉴的经验。

关键词：刘欣翠西福克斯辩论中美“贸易战” 民间外交

A Meta-analysis of Molecular Spectroscopy Databases,and Prospects of Molecule Detection with Some Future Facilities

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Research in Astronomy and Astrophysics 2022年第10期22卷 165-179页

作者： Xin Liu Fujun Du Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

Molecules reside broadly in the interstellar space and can be detected via spectroscopic observations.To date,more than 271 molecular species have been identified in interstellar medium or circumstellar envelopes.Molecular spectroscopic parameters measured in laboratory make the identification of new species and derivation of physical parameters possible.These spectroscopic parameters are systematically collected into databases,two of the most commonly used being the CDMS and JPL databases.While new spectroscopic parameters are continuously measured/calculated and added to those databases,at any point in time it is the existing spectroscopic data that ultimately limits what molecules can possibly be identified in astronomical data.In this work,we conduct a meta-analysis of the CDMS and JPL databases.We show the statistics of transition frequencies and their uncertainties in these two databases,and discuss the line confusion problem under certain physical environments.We then assess the prospects of detecting molecules in common ISM environments using a few facilities that are expected to be conducting spectroscopic observations in the future.Results show that CSST/HSTDM and SKA1-mid have the potential to detect some complex organic molecules,or even amino acids,with reasonable assumptions about ISM environments.

关键词： Catalogs-Molecular data-ISM molecules

The convergence properties of infeasible inexact proximal alternating linearized minimization

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Science China Mathematics 2023年第10期66卷 2385-2410页

作者： Yukuan Hu Xin Liu State Key Laboratory of Scientific and Engineering Computing Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

The proximal alternating linearized minimization(PALM)method suits well for solving blockstructured optimization problems,which are ubiquitous in real applications.In the cases where subproblems do not have closed-form solutions,e.g.,due to complex constraints,infeasible subsolvers are indispensable,giving rise to an infeasible inexact PALM(PALM-I).Numerous efforts have been devoted to analyzing the feasible PALM,while little attention has been paid to the PALM-I.The usage of the PALM-I thus lacks a theoretical guarantee.The essential difficulty of analysis consists in the objective value nonmonotonicity induced by the infeasibility.We study in the present work the convergence properties of the PALM-I.In particular,we construct a surrogate sequence to surmount the nonmonotonicity issue and devise an implementable inexact criterion.Based upon these,we manage to establish the stationarity of any accumulation point,and moreover,show the iterate convergence and the asymptotic convergence rates under the assumption of the Lojasiewicz property.The prominent advantages of the PALM-I on CPU time are illustrated via numerical experiments on problems arising from quantum physics and 3-dimensional anisotropic frictional contact.

关键词： proximal alternating linearized minimization infeasibility nonmonotonicity surrogate sequence inexact criterion iterate convergence asymptotic convergence rate

Catalytic conversion and DFT analysis of post DDBD-catalysis system for degradation of toluene,ethyl acetate and acetone with different metal-oxides catalysts

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Journal of Rare Earths 2023年第2期41卷 215-223页

作者： Xin Liu Jianqi liu Jiayao Chen Fangchuan Zhong College of Environmental Science and Engineering Donghua UniversityShanghai 201620China College of Science Donghua UniversityShanghai 201620China Member of Magnetic Confinement Fusion Research Centre Ministry of EducationShanghai 201620China

A series of multiphase metal-oxide catalysts(MnOx/γ-Al_(2)O_(3),CuOx/γ-Al_(2)O_(3),FeO_(x/γ)-Al_(2)O_(3),CeO_(x)/γ-Al_(2)O_(3)and LaOx/γ-Al_(2)O_(3))were prepared for plasma-catalyst degradation of multicomponent volatile organic compounds(VOCs,such as toluene,acetone and ethyl acetate).The results reveal that the degradation efficiency(DE)of acetone,toluene and ethyl acetate in the DDBD system can be arranged as follows:Mn_(2)O_(3)/γ-Al_(2)O_(3)>Fe2O3/γ-Al_(2)O_(3)>CuO_(/γ)-Al_(2)O_(3)>CeO_(2)/γ-Al_(2)O_(3)>La_(2)O_(3)/γ-Al_(2)O_(3)>γ-Al_(2)O_(3),and the highest DE(49.5%for acetone,93.3%for toluene and 79.8%for ethyl acetate)is obtained in Mn_(2)O_(3)/γ-Al_(2)O_(3)+double dielectric barrier discharge(DDBD)system at specific input energy(SIE)of 700 J/L.Compared with the other catalysts,Mn_(2)O_(3)/γ-Al_(2)O_(3)also exhibits the most significant inhibitory effect on the production of ozone(O3).On the other hand,CeO_(2)/γ-Al_(2)O_(3)and La_(2)O_(3)/γ-Al_(2)O_(3)catalysts display different catalytic selectivity.Both catalysts can slightly raise the DE of VOCs and remarkably facilitate VOCs’mineralization.The carbon balance(CB)is increased by 30.2%and 38.8%,and the CO_(2)selectivity(SCO_(2))is raised by 70.5%and 11.9%in the CeO_(2)/γ-Al_(2)O_(3)+DDBD system and La_(2)O_(3)/γ-Al_(2)O_(3)+DDBD system at SIE of 700 J/L,respectively.To further understand the catalytic effect of the catalysts,the adsorption of O3on different catalysts was simulated by a DFT model.According to the results of the DFT model,it is found that the adsorption energy of other metal oxides seems to be used as a reference for catalytic effect to a certain extent except CeO_(2).The higher the absolute values of adsorption energy,the higher the improvement of VOCs degradation efficiency by catalyst.

关键词： Multiphase metal-oxide catalysts Plasma-catalyst Multicomponent volatile organic compounds Rare earths

High-Tc superconductor Fe(Se,Te) monolayer:an intrinsic,scalable and electrically tunable Majorana platform

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National Science Review 2022年第3期9卷 11-18页

作者： Xianxin Wu Xin Liu Ronny Thomale Chao-xing liu Institut für Theoretische Physik und Astrophysik Julius-Maximilians-Universit?t Würzburg School of Physics Huazhong University of Science and Technology Wuhan National High Magnetic Field Center Huazhong University of Science and Technology Department of Physics the Pennsylvania State University

Iron-based superconductors have been identified as a novel platform for realizing Majorana zero modes(MZMs) without heterostructures, due to their intrinsic topological properties and high-Tc superconductivity. In the two-dimensional limit, the FeTe1-xSexmonolayer, a topological band inversion has recently been experimentally observed. Here, we propose to create MZMs by applying an in-plane magnetic field to the FeTe1-xSexmonolayer and tuning the local chemical potential via electric gating.Owing to the anisotropic magnetic couplings on edges, an in-plane magnetic field drives the system into an intrinsic high-order topological superconductor phase with Majorana corner modes. Furthermore, MZMs can occur at the domain wall of chemical potentials at either one edge or certain type of tri-junction in the two-dimensional bulk. Our study not only reveals the FeTe1-xSexmonolayer as a promising Majorana platform with scalability and electrical tunability and within reach of contemporary experimental capability,but also provides a general principle to search for realistic realization of high-order topological superconductivity.

关键词： high-order topological superconductivity Majorana zero modes iron-based superconductors

Progress of fundamental mechanism of formic acid decomposition and electrooxidation

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Journal of Energy Chemistry 2022年第7期31卷 292-309,I0008页

作者： Xin Liu Timo Jacob Wang Gao Key Laboratory of Automobile Materials Ministry of EducationDepartment of Materials Science and Engineering Jilin UniversityChangchun 130022JilinChina Institute of Electrochemistry Ulm UniversityD-89081 UlmGermany

Formic acid(HCOOH) is considered as a promising viable fuel-cell ingredient for low temperature proton-exchange membrane fuel cells as a consequence of their high safety and energy density. As one prototype reaction, the study of HCOOH decomposition and electrooxidation is also helpful to understand the reaction mechanism of other small molecular organics. Herein, we present a comprehensive overview of HCOOH decomposition and electrooxidation in different environment conditions and analyze the reaction mechanism from both experimental and theoretical point of view. Furthermore, we discuss the known strategies for improving the performance of HCOOH decomposition and electrooxidation catalysts. Finally, this review presents a prospect for the future study of HCOOH decomposition and electrooxidation.

关键词： Electrochemical catalysis Density functional theory Formic acid Spectroelectrochemistry Fuel cell

ZIF-derived holey electrode with enhanced mass transfer and N-rich catalytic sites for high-power and long-life vanadium flow batteries

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Journal of Energy Chemistry 2022年第9期31卷 545-553,I0015页

作者： Yongbin liu Lihong Yu Xin Liu Le liu Jingyu Xi Institute of Materials Research Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina School of Materials&Environmental Engineering Shenzhen PolytechnicShenzhen 518055GuangdongChina

Electrode materials with good redox kinetics,excellent mass transfer characteristics and ultra-high stability play a crucial role in reducing the life-cycle cost and prolonging the maintenance-free time of the vanadium flow batteries(VFB).Herein,a nitrogen-doped porous graphite felt electrode(N-PGF)is proposed by growing ZIF-67 nanoparticles on carbon fibers and then calcinating and acid etching.The multi-scale structure of“carbon fiber gap(electrolyte flow),micro/nano pore(active species diffusion)and Nitrogen active center(reaction site)”in N-PGF electrode effectively increases the catalytic sites and promotes mass transfer characteristics.Reasonable electrode design makes the battery show excellent rate performance and ultra-high cycling stability.The peak power density of the battery reaches 1006 mW cm^(-2).During 1000 cycles at 150 mA cm^(-2),the average discharge capacity and average discharge energy of N-PGF increase substantially by 11.6%and 23.4%compared with the benchmark thermal activated graphite felt,respectively.More excitingly,after ultra-long term(5000 cycles)operation at an ultra-high current density(300 mA cm^(-2)),N-PGF exhibits an unprecedented energy efficiency retention(99.79%)and electrochemical performance stability.

关键词： Vanadium flow battery Multi-scale pore electrode Graphite felt Nitrogen-doping Cycling stability

Defect-rich porous tubular graphitic carbon nitride with strong adsorption towards lithium polysulfides for high-performance lithium-sulfur batteries

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Journal of Materials Science & Technology 2022年第20期115卷 140-147页

作者： Heng Ma Xin Liu Ning liu Yan Zhao Yongguang Zhang Zhumabay Bakenov xin Wang School of Materials Science and Engineering Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control TechnologyHebei University of TechnologyTianjin 300130China Institute of Batteries LLC School of Engineering and Digital SciencesNational Laboratory AstanaNazarbayev University53 Kabanbay Batyr AvenueNur-Sultan 010000Kazakhstan South China Academy of Advanced Optoelectronics International Academy of Optoelectronics at ZhaoqingSouth China Normal UniversityGuangzhou 510006China

The commercialization of the lithium-sulfur(Li-S)batteries is severely hampered by the shuttle effect and sluggish kinetics of lithium polysulfides(Li PSs).In this study,porous tubular graphitic carbon nitride(PTCN)was synthesized as the sulfur host by hydrothermal treatment,thermal shock and etching methods.By etching technology,the hollow nanotube tentacles grow on the tube wall of PTCN,the mesoporous appears on the inner wall,and a large number of nitrogen defects are introduced.The verticallyrooted hollow nanotube tentacles on the PTCN surface facilitate electron conduction for sulfur redox reactions.The hollow and porous architecture exposes plentiful active interfaces for accelerated redox conversion of polysulfide.Furthermore,the nitrogen defects in PTCN enable more excellent intrinsic conductivity,higher adsorbability and conversion catalytic activity to Li PSs.Based on the above synergetic effect,the batteries with PTCN/S cathodes realize a high discharge capacity of 504 m Ah g^(-1) at 4 C and a stable cycling behavior over 500 cycles with a low capacity decay of 0.063%per cycle.The results indicate a promising approach todesigning a high performance electrode material for Li-S batteries.

关键词： Lithium-sulfur batteries Porous tubular graphitic carbon nitride Sulfur host Nitrogen defects

Characteristics of Mandarin Open-set Word Recognition Development among Chinese Children with Cochlear Implants

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Chinese Medical Journal 2017年第20期130卷 2410-2415页

作者： Ying Kong Xin Liu Sha liu Yong-xin Li Beijing Tongren Hospital Capital Medical University Beijing Institute of Otolaryngology Key Laboratory of Otolaryngology-Head and Neck Surgery Capital Medical University Ministry of Education Beijing 100005 China China Rehabilitation Research Center for Hearing and Speech Impairment Beijing 100029 China Department of Otolaryngology Head and Neck Surgery Beijing Tongren Hospital Capital Medical University Key Laboratory of Otolaryngology Head and Neck Surgery Capital Medical University Ministry of Education Beijing 100730 China

Background： Cochlear implants （Cls） can improve speech recognition for children with severe congenital hearing loss, and open-set word recognition is an important efficacy measure. This study examined Mandarin open-set word recognition development among Chinese children with Cls and normal hearing （NH）. Methods： This study included 457 children with CIs and 131 children with NH, who completed the Mandarin lexical neighborhood test. The results for children at 1-8 years alter receiving their Cls were compared to those from the children with NH using linear regression analysis and analysis of variance. Results： Recognition of disyllabic easy words, disyllabic hard words, monosyllabic easy words, and monosyllabic hard words increased with time after CI implantation. Scores for cases with implantation before 3 years old were significantly better than those for implantation after 3 years old. There were significant differences in open-set word recognition between the CI and NH groups. For implantation before 2 years, there was no significant difference in recognition at the ages of 6-7 years, compared to 3-year-old children with NH, or at the age of 10 years, compared to 6-year-old children with NH. For implantation before 3 years, there was no significant difference in recognition at the ages of 8 9 years, compared to 3-year-old children with NH, or at the age of 10 years, compared to 6-year-old children with NH. For implantation after 3 years, there was a significant difference in recognition at the age of 13 years, compared to 3-year-old children with NH. Conclusions： Mandarin open-set word recognition increased with time after CI implantation, and the age at implantation had a significant effect on long-term speech recognition. Chinese children with Cls had delayed but similar development of recognition, compared to norrnal children. Early CI implantation can shorten the gap between children with Cls and normal children.

关键词： Children Cochlear Implantation Open-set Word Recognition