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Journal of Hydrodynamics 2024年第2期36卷 219-231页

作者： Chen Geng Zhao-hui Qian Ke-xin Zheng Wei-xiang Ye xian-wu Luo State Key Laboratory of Hydroscience cand Engineering Deparment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

In the present paper,the unsteady cavitating turbulent flow over the twisted NACA66 hydrofoil is investigated based on an modified shear stress transfer k-ωpartially averaged Navier-Stokes(MSST PANS)model,i.e.,new MSST PANS(NMSST PANS)model,where the production term of kinetic energy in the turbulence model is modified with *** with the experimental data,cavitation evolution and its characteristic frequency are satisfactorily predicted by the proposed NMSST PANS *** is revealed that the interaction among the main flow,the reentrant jets,and sheet cavitation causes the formation of the primary shedding cavity near the mid-span and the secondary shedding cavity at each side of the twisted hydrofoil,and further induces the remarkable pressure gradient around shedding *** with the development of the primary and the secondary shedding cavities,the great pressure gradient associated with large cavity volume variation promotes the vortical flow generation and the spatial deformation of vortex structure during cavitation evolution,and results in the primary and the secondary U-type ***,dynamic mode decomposition(DMD)analysis is utilized to confirm the interaction among the main flow,the main reentrant jet and two side reentrant jets,and *** results indicate that the proposed NMSST PANS model is suitable to simulate the complicated cavitating turbulent flow for various engineering applications.

关键词： Cavitating turbulent flow partially averaged Navier-Stokes(PANS)model hydrofoil numerical simulation

Vanadium(V) Complexes Containing Unsymmetrical N-Heterocyclic Carbene Ligands: Highly Efficient Synthesis and Catalytic Behavior towards Ethylene/Propylene Copolymerization

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Chinese Journal of Polymer Science 2024年第1期42卷 32-41,I0006页

作者： Yi-Cong Wang Hui Zhat Pei-Yi Cheng Shu Zhang xiang-Wei Liu Yi-xian wu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBejing 100029China

The highly efficient method has been developed for the synthesis of NHC·VOCl_(3) containing symmetrical or unsymmetrical Nheterocyclic carbene(NHC) ligands by the transmetallation reaction of NHC·AgCl with VOCl_(3).The total isolated yield of VOCl_(3)[1,3-(2,4,6-Me_(3)C_(6)H_(2))_(2)(NCH=)_(2)C:](V4') reached 86% by transmetallation reaction,which is much higher than that(48%) by direct coordination *** methodology has also been used to synthesize the novel vanadium complexes containing unsymmetrical NHC ligands of VOCl_(3)[PhCH_(2)NCH=CHNR)C:](V5',R=2,4,6-Me_(3)C_(6)H_(2);V6',R=2,4-Me_(2)-6-Ph-C_(6)H_(2);V7',R=2,6-^(i)Pr_(2)-C_(6)H_(3)) with high yield,which could not be obtained by direct coordination *** catalytic activity and copolymerization ability would be improved by introducing unsymmetrical NHC ligands due to their less steric bulky *** vanadium complex V5' containing unsymmetrical NHC ligand exhibits higher catalytic activity(3.7×10^(5)g_(copolymer)·mol^(-1) of V·h^(-1)) than that of V4' containing symmetrical NHC ***,the higher propylene incorporation ratio(45.6 mol%) in the copolymers of ethylene with propylene could be obtained by using V5' than that(39.9%) by using V4'.The results would provide a highly efficient strategy for the synthesis of early transition metal complexes containing versitile NHC ligands,affording the catalyst with both high catalytic activity and copolymerization ability for the synthesis of high performance polyolefin elastomers.

关键词： Vanadium complex N-heterocyclic carbene ligand Transmetallation reaction Copolymerization of ethylene with propylene

Level pinning of anti-PT-symmetric circuits for efficient wireless power transfer

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National Science Review 2024年第1期11卷 215-224页

作者： Zhiwei Guo Fengqing Yang Haiyan Zhang xian wu Qiong wu Kejia Zhu Jun Jiang Haitao Jiang Yaping Yang Yunhui Li Hong Chen MOE Key Laboratory of Advanced Micro-Structured Materials School of Physics Sciences and Engineering Tongji University Department of Electrical Engineering Tongji University School of Automotive Studies Tongji University

Wireless power transfer(WPT) technology based on magnetic resonance(a basic physical phenomenon)can directly transfer energy from the source to the load without wires and other physical contacts, and has been successfully applied to implantable medical devices, electric vehicles, robotic arms and other ***, due to the frequency splitting of near-field coupling, the resonant WPT system has some unique limitations, such as poor transmission stability and low efficiency. Here, we propose anti-resonance with level pinning for high-performance WPT. By introducing the anti-resonance mode into the basic WPT platform, we uncover the competition between dissipative coupling and coherent coupling to achieve novel level pinning, and construct an effective anti-parity-time(anti-PT)-symmetric non-Hermitian system that is superior to previous PT-symmetric WPT schemes. On the one hand, the eigenvalue of the anti-PT-symmetric system at resonance frequency is always pure real in both strong and weak coupling regions, and can be used to overcome the transmission efficiency decrease caused by weak coupling, as brought about by, for example, a large size ratio of the transmitter to receiver, or a long transmission *** the other hand, due to the level pinning effect of the two kinds of coupling mechanisms, the working frequency of the system is guaranteed to be locked, so frequency tracking is not required when the position and size of the receiver change. Even if the system deviates from the matching condition, an efficient WPT can be realized, thereby demonstrating the robustness of the level pinning. The experimental results show that when the size ratio of the transmitter coil to the receiver coil is 4.29(which is in the weak coupling region), the transfer efficiency of the anti-PT-symmetric system is nearly 4.3(3.2) times higher than that of the PT-symmetric system when the matching conditions are satisfied(deviated). With the miniaturization and integration of d

关键词： non-Hermitian system wireless power transfer anti-PT-symmetric circuits synthetic dimension metamaterials

Metallaphotoredox-Catalyzed Three-Component Couplings for Practical Synthesis of Ureas and Carbamates

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Chinese Journal of Chemistry 2024年第3期42卷 264-270页

作者： Ernest Koranteng Zhen-Cao Shu Yi-Yin Liu Qian Yang Bin Shi Qiang-xian wu Fen Tan Liang-Qiu Lu Wen-Jing Xiao Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University152 Luoyu RoadWuhanHubei430079 China wuhan Youji Industries Co. LtdNo.1 2nd Chemical Rd.WuhanHubei430082 China Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients School of Chemistry and Life SciencesHubei University of EducationWuhanHubei430205 China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China wuhan Institute of Photochemistry and Technology WuhanHubei430082 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032 China

Ureas are widely used in drugs,materials and catalysts because of their diamide structure,which can form strong hydrogen ***,it is of great scientific significance to develop efficient and green methods for the synthesis of urea compounds,especially unsymmetrical ***,we have disclosed novel and highly efficient three-component coupling reactions of organic halides,sodium cyanate and amines enabled by nickel/photoredox dual catalysis for the preparation of unsymmetrical *** reaction features simple and safe operations,broad substrate scopes,and product *** allows the facile synthesis of N-aryl/vinyl ureas from readily available,user-friendly feedstocks under mild conditions(27 examples,36%—98%yields).In addition,this method is further derived to alcohols as nucleophiles to synthesize a series of carbamates(15 examples,40%—95%yields).The mechanism experiment shows that the isocyanate produced by the coupling of halide and sodium cyanate may be the key intermediate in this reaction.

关键词： Cross-coupling Nickel Photoredox catalysis Three-component reaction Ureas Carbamates

Non-Gaussianity detection of single-mode rotationally symmetric quantum states via cumulant method

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Chinese Physics B 2024年第5期33卷 264-273页

作者：向少华黄利军米贤武 College of Physics Electronics and Intelligent ManufacturingHuaihua UniversityHuaihua 418008China

The non-Gaussianity of quantum states incarnates an important resource for improving the performance of continuous-variable quantum information *** propose a novel criterion of non-Gaussianity for single-mode rotationally symmetric quantum states via the squared Frobenius norm of higher-order cumulant matrix for the quadrature distribution *** an application,we study the non-Gaussianities of three classes of single-mode symmetric non-Gaussian states:a mixture of vacuum and Fock states,single-photon added thermal states,and even/odd Schr¨odinger cat *** is shown that such a criterion is faithful and effective for revealing *** further extend this criterion to two cases of symmetric multi-mode non-Gaussian states and non-symmetric single-mode non-Gaussian states.

关键词： non-Gaussianity criterion cumulant matrix quadrature distribution

Promotion and Mechanism of Acupotomy on Chondrocyte Autophagy in Knee Osteoarthritis Rabbits

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Chinese Journal of Integrative Medicine 2024年第9期30卷 809-817页

作者： LU Man MENG De-hong SHE Ze-yu wu xian XIA Shuai YANG Kai-ning LIU Cun-bin LI Tao YANG Yong-hui The First Affiliated Hospital of Anhui University of Chinese Medicine Hefei230031China The Second Affiliated Hospital of Anhui University of Chinese Medicine Hefei230038China Department of Acupotomy Rehabilitation Anhui Provincial Hospital of Integrated Traditional Chinese and Western MedicineHefei230031China

Objective:To explore the effect of acupotomy intervention on autophagy of chondrocytes in rabbits with knee osteoarthritis(KOA),and to determine the possible mechanisms of acupotomy to alleviate cartilage ***:The modified Videman method was used to construct a KOA rabbit *** modeling,40 rabbits were randomly divided into 4 groups by a random number table:control;KOA(model);KOA+acupotomy(acupotomy),and KOA+sham acupotomy(sham),10 in each *** a 3-week treatment course,the knee joint activity was determined by the modified Lequesne MG ***-eosin staining staining was used to examine the morphological changes of *** of chondrocytes was observed by transmission electron *** surface morphology of cartilage tissue was observed by scanning electron *** mRNA and protein levels of AMP kinase/mammalian target of rapamycin/Unc-51(AMPK/mTOR/ULK1)signal pathway key proteins,autophagy-related factor Beclin-1 and microtubule-associated protein 1A/1B light chain 3(LC3)in rabbit knee cartilage were assessed by real-time fluorescence quantitative polymerase chain reaction and Western blot,***:The modified Lequesne MG score of acupotomy group was significantly lower than that of model group(P<0.05).Pathological results showed that chondrocyte autophagy decreased and cartilage surface was rough in the model group,which recovered after acupotomy *** mRNA expressions of AMPK,ULK1,Beclin-1 and the protein levels of p-AMPK,p-ULK1,Beclin-1,and LC3Ⅱ/LC3Ⅰwere decreased in the model group,while the mRNA and protein expressions of mTOR were increased(P<0.01).However,acupotomy treatment reversed these abnormal changes(P<0.05).Conclusions:Acupotomy could effectively up-regulate the expressions of AMPK,ULK1 and Beclin1,reduce the expression of mTOR,promote autophagy,and alleviate joint *** is a promising complementary and alternative therapy for KOA.

关键词： acupotomy knee asteoarthritis autophagy AMPK/mTOR/ULK1 signaling pathway rabbit

突破价值链网络化制裁——企业结构性权力与中美中间品贸易

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世界经济与政治 2024年第8期 69-98,156页

作者：吴限北京大学国际关系学院北京100871

在国际经贸关系与经济制裁实践中,关税传统上体现为对最终品设置贸易壁垒,旨在限制目标国出口并增加其经济成本。2018年以来,美国对中国加征的新型关税在形式上针对中间品贸易、在目的上企图使中国从全球价值链中脱嵌,体现出价值链网络... 详细信息

在国际经贸关系与经济制裁实践中,关税传统上体现为对最终品设置贸易壁垒,旨在限制目标国出口并增加其经济成本。2018年以来,美国对中国加征的新型关税在形式上针对中间品贸易、在目的上企图使中国从全球价值链中脱嵌,体现出价值链网络化制裁的特征。值得注意的是,美国对华价值链网络化制裁在不同产业之间的烈度存在较大差异,如中美医药产业之间的向后连接体现出较强韧性,信息技术产业却遭受了重大冲击,这种差异辐射到了整个中美经贸格局中。通过挖掘逐利行为体企业和逐权行为体国家的相互关系,作者尝试构筑以常驻美国企业为核心的国内政治解释框架:常驻美国企业借助其在美国国内的两种结构性权力以对抗和制约美国政府将经济关系武器化的行为,即企业在美国政府决策结构中的参与性权力及其在政治议程结构中的议价性权力。在“铁锈带”以外的非战略产业中,企业若能掌握两种结构性权力中的一种,便能够降低价值链网络化制裁烈度并减轻其对中美经贸格局的负面滞后效应。而在“铁锈带”之外的战略产业中,企业必须同时掌握两种结构性权力,才能有效缓解价值链网络化制裁并推进中美中间品贸易的发展。

关键词：价值链网络化制裁企业结构性权力中间品贸易中美经贸摩擦大国战略竞争

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能而不为:儒学中的意志无力问题

湖北大学学报（哲学社会科学版） 2024年第2期51卷 1-9页

作者：吴先伍南京师范大学公共管理学院江苏南京210023

意志无力是一个来源于西方的伦理学概念,西方更加关注“知”,主要是从知而不行来理解,而儒学则更加关注“能”,以能而不为来概括。这与二者面临的不同问题相关:西方是为了弥合苏格拉底的“美德即知识”与世俗当中知而不行现象之间的裂隙... 详细信息

意志无力是一个来源于西方的伦理学概念,西方更加关注“知”,主要是从知而不行来理解,而儒学则更加关注“能”,以能而不为来概括。这与二者面临的不同问题相关:西方是为了弥合苏格拉底的“美德即知识”与世俗当中知而不行现象之间的裂隙;儒学则是为了杜绝人们以能力不足为借口而拒绝践行仁义。能而不为虽然与知而不行之间存在差异,但是它同样可以归结为意志无力,因为知而不行本身就预设了“能”,能而不为也包含了“知”,二者具有高度的统一性。更为重要的是,能而不为不仅强调了能知,而且强调了能为,并且突出了能感,从而更加全面地反映了意志无力。儒学以能而不为讲意志无力,实际上是强调人们承担责任的合理性,反对人们以能力不足为借口来逃避责任,因而,能而不为具有强烈的责任意蕴。人们不仅要为他者承担责任,而且具有完善自我的道德责任。儒学讲能而不为不仅丰富了意志无力的内容,而且推动了道德认知向道德行为的转化。

关键词：儒学意志无力知而不行能而不为道德责任

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儒家有意志自由吗?——以康德为参照

东南大学学报（哲学社会科学版） 2024年第1期26卷 15-24,150页

作者：吴先伍南京师范大学公共管理学院江苏南京210023

儒家是否具有意志自由是一个聚讼纷纭的议题:有人以康德为标准,否认儒家具有意志自由;有人则认为儒家具有意志自由。意志自由是多样性的,既有康德所坚持的本体论意义上的意志自由,也有康德所反对的心理学意义上的意志自由,后者比前者更... 详细信息

儒家是否具有意志自由是一个聚讼纷纭的议题:有人以康德为标准,否认儒家具有意志自由;有人则认为儒家具有意志自由。意志自由是多样性的,既有康德所坚持的本体论意义上的意志自由,也有康德所反对的心理学意义上的意志自由,后者比前者更加符合实际。儒家从现实出发,其意志自由是心理学意义上的意志自由,人虽受到现实限定,但又高度自由。以儒家性善论来否定儒家具有意志自由不能成立,性善论虽然在一定程度上规定了人们的为善方向,但并没有剥夺人们的选择自由。正是因为人性善,道德构成了人的本质规定性,所以,对于人来说,最重要的问题不是意志自由,而是通过承担道德责任成为道德之人,意志自由后于道德责任,意志自由受到道德的限定。

关键词：儒家康德意志自由性善论道德责任

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国际战略传播:日本的理念、能力建设及启示

亚太安全与海洋研究 2024年第3期 107-124,I0004页

作者：吴限中国社会科学院日本研究所中日社会文化研究中心北京100007

日本的国际战略传播建构以推进体系机制建设和强化传播能力为中心,旨在提升与安保战略的适配度,强化舆论战、思想战能力,维护国家利益、塑造国家形象,进而推进其价值观外交。日本国际战略传播能力、传播生态及其体系机制构建的关键,是... 详细信息

日本的国际战略传播建构以推进体系机制建设和强化传播能力为中心,旨在提升与安保战略的适配度,强化舆论战、思想战能力,维护国家利益、塑造国家形象,进而推进其价值观外交。日本国际战略传播能力、传播生态及其体系机制构建的关键,是建立一套由首相官邸领导和外务省主导的能够充分培养外宣人才,承接官民两轨外宣渠道需求、增容社交网络资源,广域多维、高效协同的现代传播体系。其策略为有效利用传统媒体与新媒体以及文化符号系统,实施分众化、在地性和植入式传播,以宣传日本的政策主张、文化魅力等,塑造有利日本的文化心理和国际舆论环境。日本加速构建国际战略传播,推动其传统外宣向主体性、主导型外宣转化,实现外宣战略、外交战略和国家战略三位一体的转变。

关键词：日本国际战略传播传播理念传播体系传播生态新媒体