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Breaking the efficiency limitations of dissipative Kerr solitons using nonlinear couplers

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Science china(Physics,mechanics & Astronomy) 2024年第3期67卷 88-94页

作者： ming Li Xiao-Xiao Xue Yan-Lei Zhang Xin-Biao Xu Chun-Hua dong Guang-Can Guo Chang-Ling Zou CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Centerfor Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua University Beijing 100084China

Dissipative Kerr solitons(DKS) have long been suffering from poor power conversion efficiency when driven by continuous-wave lasers. By deriving the critical coupling condition of a multimode nonlinear optics system in a generalized theoretical framework,two efficiency limitations of the conventional pump method of DKS are revealed: the effective coupling rate is too small and is also power-dependent. A general approach is provided to resolve this challenge by introducing two types of nonlinear couplers to couple the soliton cavity and CW input through nonlinear processes. The collective coupler opens multiple coupling channels and the self-adaptive coupler builds a power-independent effective external coupling rate to the DKS for approaching the generalized critical coupling condition, which promises near-unity power conversion efficiencies. For instance, a conversion efficiency exceeding 90% is predicted for aluminum nitride microrings with a nonlinear coupler utilizing second-harmonic generation. The mechanism applies to various nonlinear processes, including Raman and Brillouin scattering, and thus paves the way for micro-solitons toward practical applications.

关键词： Kerr frequency comb conversion efficiency nonlinear coupler

TWO METHODS OF SOLVING DYNAMIC RESPONSE BY DISCRETIZATION OF GURTIN VARIATIONAL PRINCIPLE

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Acta Mechanica Sinica 1985年第2期1卷 171-183页

作者： Zhang Ruqing dong ming {2. of Mechanical Engineering, Chongqing university 1. department of Mechanical Engineering Chongqing University Chongqing China

Based on the Gurtin variational principle and the finite element method two recurrenceformulae of solving dynamic response are derived in this paper. The first recurrence formula which isconditionally stable is obtained by adopting "dual temporal finite element" to discretize the Gurtinvariational principle and then making use of convolution, while the second, an unconditionally stableone derived by discritizing the variational principle in each time step and taking appropriateintegration parameter θ.

关键词： variational principle structural dynamics computer mechanics finite element analysis.

Donor liver natural killer cells alleviate liver allograft acute rejection in rats

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Hepatobiliary & Pancreatic Diseases International 2011年第4期10卷 386-392页

作者： Jian-dong Yu,Tian-Zhu Long,Guo-Lin Li,Li-Hong Lv,Hao-ming Lin,Yong-{2. Huang,Ya-Jin Chen and Yun-Le Wan department of Hepatobiliary Surgery,Sun Yat-Sen Memorial Hospital,Sun Yat-Sen university,Guangzhou 51012.,china department of Breast Surgery,Guangzhou Women and Children’s Medical Center,Guangzhou 51012.,china [a] department of Hepatobiliary Surgery Sun Yat-Sen Memorial Hospital Sun Yat-Sen University Guangzhou 510120 China [b] department of Breast Surgery Guangzhou Women and Children's Medical Center Guangzhou 510120 China

BACKGROUND:Liver enriched natural killer (NK) cells are of high immune ***,the function of donor liver NK cells in allogeneic liver transplantation (LTx) remains ***:Ten Gy of whole body gamma-irradiation (WBI) from a 60 Co source at 0.6 Gy/min was used for depleting donorderived leukocytes,and transfusion of purified liver NK cells isolated from the same type rat as donor (donor type liver NK cells,dtl NKs) through portal vein was performed immediately after grafting the irradiated ***-transplant survival observation on recipients and histopathological detection of liver grafts were adoptive to evaluate the biological impact of donor liver NK cells on recipients’ survival in rat ***:Transfusion of dtl NKs did not shorten the survival time among the recipients of spontaneous tolerance model (BN to LEW rat) after rat LTx,but prolonged the liver graft survival among the recipients depleted of donor-derived leukocytes in the acute rejection model (LEW to BN rat).Compared to the recipients in the groups which received the graft depleted of donor-derived leukocytes,better survival and less damage in the allografts were also found among the recipients in the two different strain combinations of liver allograft due to transfusion of dtl ***:Donor liver NK cells alone do not exacerbate liver allograft acute ***,they can alleviate it,and improve the recipients’ survival.

关键词： liver transplantation natural killer cell donor transfusion graft rejection

Scattering of Tollmien-Schlichting waves by localized roughness in transonic boundary layers

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Applied Mathematics and mechanics(English Edition) 2020年第7期41卷 1105-1124页

作者： ming dong department of mechanics Tianjin UniversityTianjin 300072China Laboratory for High-Speed Aerodynamics Tianjin UniversityTianjin 300072China

The laminar-turbulent transition in boundary-layer flows is often affected by wall imperfections, because the latter may interact with either the freestream perturbations or the oncoming boundary-layer instability modes, leading to a modification of the accumulation of the normal modes. The present paper particularly focuses on the latter mechanism in a transonic boundary layer, namely, the effect of a two-dimensional(2.D) roughness element on the oncoming Tollmien-Schlichting(T-S) modes when they propagate through the region of the rapid mean-flow distortion induced by the roughness. The wave scattering is analyzed by adapting the local scattering theory developed for subsonic boundary layers(WU, X. S. and {2., M. A local scattering theory for the effects of isolated roughness on boundary-layer instability and transition: transmission coefficient as an eigenvalue. Journal of Fluid mechanics, 794, 68–108(2.06)) to the transonic regime, and a transmission coefficient is introduced to characterize the effect of the roughness. In the sub-transonic regime, in which the Mach number is close to, but less than, 1, the scattering system reduces to an eigenvalue problem with the transmission coefficient being the eigenvalue;while in the super-transonic regime, in which the Mach number is slightly greater than 1, the scattering system becomes a high-dimensional group of linear equations with the transmission coefficient being solved afterward. In the largeReynolds-number asymptotic theory, the K′arm′an-Guderley parameter is introduced to quantify the effect of the Mach number. A systematical parametric study is carried out,and the dependence of the transmission coefficient on the roughness shape, the frequency of the oncoming mode, and the K′arm′an-Guderley parameter is provided.

关键词： boundary layer scattering instability Tollmien-Schlichting(T-S)wave triple deck

Interpretation of gas-film cooling against aero-thermal heating for high-speed vehicles

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Applied Mathematics and mechanics(English Edition) 2016年第12期37卷 1615-1630页

作者： ming dong department of mechanics Tianjin UniversityTianjin 300072China tianjin Key Laboratory of Modern Engineering mechanics Tianjin 300072China

The possible application of the film-cooling technique against aero-thermal heating for surfaces of high-speed flying vehicles is discussed. The technique has been widely used in the heat protection of gas turbine blades. It is shown in this paper that, by applying this technique to high-speed flying vehicles, the working principle is fundamentally different. Numerical simulations for two model problems axe performed to support the argument. Besides the heat protection, the appreciable drag reduction is found to be another favorable effect. For the second model problem, i.e., the gas cooling for an optical window on a sphere cone, the hydrodynamic instability of the film is studied by the linear stability analysis to observe possible occurrence of laminar-turbulent transition.

关键词： film cooling aero-thermal heating numerical simulation laminar-turbulenttransition linear stability analysis

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基于逆有限元法的三维壁板结构变形场重构

工程力学 2024年第6期41卷 235-245页

作者：胡明月吴邵庆董萼良东南大学土木工程学院工程力学系江苏南京211189 东南大学江苏省工程力学分析重点实验室江苏南京211189 东南大学江苏省空天机械装备工程研究中心江苏南京211189

过约束状态下的结构内部转角不连续,会导致结构变形场难以准确重构。该文以飞行器进气道典型三维壁板结构为对象,开展超静定状态下结构变形场重构方法研究。将子区域划分与逆有限元法相结合,实现了基于实测应变数据的超静定结构全场变... 详细信息

过约束状态下的结构内部转角不连续,会导致结构变形场难以准确重构。该文以飞行器进气道典型三维壁板结构为对象,开展超静定状态下结构变形场重构方法研究。将子区域划分与逆有限元法相结合,实现了基于实测应变数据的超静定结构全场变形重构。对静载工况下三维壁板结构开展变形场重构数值仿真研究,验证算法的可行性和重构精度;进一步开展了试验研究,实现了变载荷工况下基于实测应变的三维壁板结构全场变形重构,并利用实测位移数据验证重构变形场的精度。试验结果表明:位移测点处的重构位移值与实测位移值的相对误差在10%左右,结合子区域划分和逆有限元法的变形重构算法可以准确重构出过约束工况下三维壁板结构的全场变形。

关键词：工程力学全场变形重构逆有限元法三维壁板结构子区域划分

Investigation on Molecular and Crystal Structures of Metal Complexes with Aminopolycarboxylic Acids(Ⅰ)─Synthesis and Structure of Na_2.Fe~Ⅲ(ida)2.2.3H_2.

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Chinese Chemical Letters 1997年第8期8卷 741-744页

作者： Jun WANG Wei Qun ZHANG Xi ming SONG Xiang dong ZHANG ({2. of Chemistry, Liaoning university,Shenyang 110036)Yan XING Yong Hua LIN heng Qing JIA Lei ZHANG(Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 13002.) department of Chemistry Liaoning University Shenyang 110036 China Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130024 China

The crystal structure of the title complex salt has been determined by single-crystal X-ray structure analysis. The crystal data are as follows; Monoclinic, P2./c, a=15.6480(10)A,b=16.7870(10)A, c=10.347(2.A, β=90.790(10), V=2.17.7(6)A3, Z=3, and R=0.0333 for 4789 unique reflections. The complex anion has a pseudo-octahedral structure distorted more than the CrⅢand CoⅢ analogs, in which cach iminodiacetato ligand (ida2.) is coordinated in a facial fashion with the two N atoms in a cis configuration, resulting in an unsyin-fac structure.

关键词： Na Synthesis and Structure of Na2.Fe Investigation on Molecular and Crystal Structures of Metal Complexes with Aminopolycarboxylic Acids ida)2.2

基于肌骨动力学与有限元耦合模型的脊柱生物力学研究应用进展

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应用力学学报 2024年第1期41卷 233-240页

作者：杜娟夏晓宇孟琳苗军明东天津大学医学工程与转化医学研究院天津300072 天津大学天津医院脊柱二科天津300210

由于现代生活方式的改变与人口老龄化,近年来脊柱疾病发病率急剧升高。生物力学研究是评估脊柱相关疾病的重要内容,通过建模仿真的方法探究脊柱生物力学一直是重要的手段之一。目前,结合肌骨模型与有限元的方法成为脊柱生物力学的研究热... 详细信息

由于现代生活方式的改变与人口老龄化,近年来脊柱疾病发病率急剧升高。生物力学研究是评估脊柱相关疾病的重要内容,通过建模仿真的方法探究脊柱生物力学一直是重要的手段之一。目前,结合肌骨模型与有限元的方法成为脊柱生物力学的研究热点,因此,本研究对国内外使用肌骨模型与有限元相结合的方法探究脊柱生物力学特征的文章进行调研,系统阐述了该方法在脊柱相关疾病方面的临床应用进展,总结基于这种方法的建模方式,包括加载方法、杨氏模量、泊松比等参数设置,以及使用该方法在脊柱相关疾病上的评估应用。结果表明:基于肌骨动力学与有限元的方法,对探究人体在体运动时脊柱组织层面的应力应变、椎间盘内压力(intervertebral disc pressure, IDP)等情况,提供了一种多尺度评估方法,但该种方法目前存在模型构建时间长、研究动作单一、需要验证模型有效性不足等问题,是未来脊柱生物力学领域研究需要研究的方向。

关键词：脊柱运动分析肌骨模型有限元

Scintillation Arc from FRB 2.2.0912.

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Science china(Physics,mechanics & Astronomy) 2024年第1期67卷 134-142页

作者： Zi-Wei Wu Robert AMain Wei-Wei Zhu Bing Zhang Peng Jiang Jia-Rui Niu Jin-Lin Han Di Li Ke-Jia Lee dong-Zi Li Yuan-Pei Yang Fa-Yin Wang Rui Luo Pei Wang Chen-Hui Niu heng Xu Bo-Jun Wang Wei-Yang Wang Yong-Kun Zhang Yi Feng De-Jiang {2. Yong-Hua Xu Can-Min Deng Yu-Hao Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut für Radioastronomie Bonn 53121Germany Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for Astrophysics and department of Physics and Astronomy University of NevadaLas VegasNV 89154USA CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Cahill Center for Astronomy and Astrophysics California Institute of TechnologyPasadena 91125USA South-Western Institute For Astronomy Research Yunnan UniversityKunming 650504China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing university) Ministry of EducationNanjing 210023China CSIRO Space and Astronomy Epping 1710Australia department of Astronomy School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Guangxi Key Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

We present the interstellar scintillation analysis of fast radio burst(FRB)2.2.0912. during its extremely active episode in 2.2.using data from the Five-hundred-meter Aperture Spherical Radio Telescope(FAST).We detect a scintillation arc in the FRB’s secondary spectrum,which describes the power in terms of the scattered FRB signals’time delay and Doppler *** arc indicates that the scintillation is caused by a highly localized *** analysis favors a Milky Way origin of the ionized interstellar medium(IISM)for the localized scattering medium but cannot rule out a host galaxy *** present our method for detecting the scintillation arc,which can be applied generally to sources with irregularly spaced bursts or *** methods could help shed light on the complex interstellar environment surrounding the FRBs and in our Galaxy.

关键词： fast radio burst scintillation FRB 2.2.0912.