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Evolution of the Lagrangian drift and vortex added-mass of a growing vortex ring

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Journal of Hydrodynamics 2021年第4期33卷 725-735页

作者： Shu-jia Lin Yang Xiang Zhuo-qi Li fu-xin wang Hong Liu School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

The vortex-based propulsive systems’ enhanced performance greatly contributes to the vortex added-mass effect, which was initially developed to explain the added drag when a solid body accelerates in fluids. However, the solution of the instantaneous vortex added-mass coefficient is still remaining a question because vortices always do not have a stable geometric shape like solid bodies. In this paper, the formation of a canonical vortex ring is performed to investigate the nature of vortex added-mass and explore a solution for estimating the vortex added-mass coefficient. The vortex ring is generated by a piston-cylinder apparatus, and the time-dependent flow fields are recorded by particle image velocimetry technique. The ridges of finite-time Lyapunov exponent are applied to identify the Lagrangian boundary of the vortex ring. It is found that a part of the ambient fluids is entrained by the vortex ring when it propagates downstream, resulting in the growth of the vortex ring. Besides, a significant drift of the ambient fluid is observed to bypass the Lagrangian boundary of the vortex ring and reveals the nature of the vortex added-mass. Thus, the added-mass coefficient of the vortex is redefined as the ratio of the volume of the Lagrangian drift fluids in finite time interval step to the vortex volume at that instant. By referring to McPhaden’s method to estimate the added-mass of a solid body, a method based on the multiple material lines with relative-timestep is developed to estimate the volume of Lagrangian drift fluids induced by the vortex added-mass. Then, an empirical criterion for determining the material line number and the finite time interval step is suggested for the vortex ring flow, and the eventual vortex added-mass coefficient calculated by the volume of Lagrangian drift fluids is found to well agree with the results of Brennen. Moreover, the method based on multiple material lines for calculating Lagrangian drift fluids’ volume suggests a poten

关键词： Added-mass Lagrangian coherent structure(LCS) finite-time Lyapunov exponent(FTLE)

Microstructures and properties of Nb-Si-based alloys with B addition

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Rare Metals 2023年第8期42卷 2801-2808页

作者： Liang-Shun Luo fu-xin wang Xian-Yu Meng Yan-Jin Xu Liang wang Yan-Qing Su Jing-Jie Guo Heng-Zhi fu School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China AVIC Manufacturing Technology Institute Beijing 100024China

The Nb-16Si-18Ti-xB(at%,similarly hereinafter,x=0,1,2,3)alloys were prepared by arc melting in a water-cooled copper *** influences of B addition on their microstructures and properties were based on the data of X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),and electronic universal material testing *** is found that the addition of B promotes the formation ofα-Nb5Si3phase and suppresses the formation of Nb3Si phase.B addition also tends Nb-16Si-18Ti alloy to form the hypereutectic *** content of silicide phases shows a trend of firstly decreasing and then increasing in Nb-16Si-18Ti-xB(x=0,1,2,3)*** size of Nb solid solution(Nbss)phase increases in Nb-16Si-18Ti-xB(x=0,1,2,3)alloys after heat treatment at 1523 K for 10 *** room temperature compression strength of Nb-16Si-18Ti alloy increases firstly and then decreases with B *** high-temperature compression strength of Nb-16Si-18Ti alloy decreases firstly and then increases with B *** is found that the volume and size of silicide phases have a synergistic effect on the compression strength of Nb-TiSi-based alloys.

关键词： Nb-Si alloys B element Phase stability Compression yield strength

Fe–Al Phase Formation Studied by Internal Friction during Heating Process

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Chinese Physics Letters 2020年第3期37卷 41-44页

作者： Gang-Ling Hao Yu-Chuan Li xing-fu wang Wei-Guo wang xin-fu wang Dan wang Xian-Yu Li College of Physics and Electronic Information Yan 5an UniversityYan'an 716000 Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031

We systematically investigate the internal friction properties of a Fe-(43 at.%)Al powder mixture compact during the heating process with the expectation to understand the phase formation and transition *** internal friction peaks are successively observed during the heating process from room temperature to 750℃,but almost completely disappear in the subsequent cooling *** internal friction peaks exhibit obvious measuring frequency dependence,which increases with decreasing the *** first internal friction peak originates from the micro-sliding of weak bonding interface between Al particles corresponding to a *** process of deformed Al *** second internal friction peak is attributed to a phase formation process associated with the formation of the intermediate phase *** third internal friction peak is considered to result from the formation of the FeAl intermetallic compound owing to the reaction of Fe2Al5 and residual Fe initiated by a dramatic thermal explosion reaction.

关键词： friction intermetallic Internal

Suppression of ice nucleation in supercooled water under temperature gradients

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Chinese Physics B 2021年第6期30卷 657-666页

作者： Li-Ping wang Wei-Liang Kong Pei-Xiang Bian fu-xin wang Hong Liu School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Understanding the behaviours of ice nucleation in non-isothermal conditions is of great importance for the preparation and retention of supercooled water. Here ice nucleation in supercooled water under temperature gradients is analyzed thermodynamically based on classical nucleation theory(CNT). Given that the free energy barrier for nucleation is dependent on temperature, different from a uniform temperature usually used in CNT, an assumption of linear temperature distribution in the ice nucleus was made and taken into consideration in analysis. The critical radius of the ice nucleus for nucleation and the corresponding nucleation model in the presence of a temperature gradient were obtained. It is observed that the critical radius is determined not only by the degree of supercooling, the only dependence in CNT, but also by the temperature gradient and even the Young's contact angle. Effects of temperature gradient on the change in free energy, critical radius,nucleation barrier and nucleation rate with different contact angles and degrees of supercooling are illustrated *** results show that a temperature gradient will increase the nucleation barrier and decrease the nucleation rate, particularly in the cases of large contact angle and low degree of supercooling. In addition, there is a critical temperature gradient for a given degree of supercooling and contact angle, at the higher of which the nucleation can be suppressed completely.

关键词： supercooled water ice nucleation temperature gradient thermodynamic analysis classical nucleation theory

The Role of Autophagy during Development of the Oomycete Pathogen Phytophthora infestans

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Journal of Genetics and Genomics 2014年第4期41卷 225-228页

作者： Qian Luo fu-xin wang Nai-Qin Zhong Hai-Yun wang Gui-Xian Xia Institute of Microbiology Chinese Academy of Sciences State Key Laboratory of Plant Genomics University of Chinese Academy of Sciences

Phytophthora infestans is a highly destructive plant path- ogen that causes late blight disease in plants such as potato and tomato （Fry and Goodwin, 1997）. As a typical oomycete, the primary infective propagule of P. infestans is the sporangium, which can either germinate directly or release biflagellate zoospores that encyst and germinate on the host subsequently （Grenville-Briggs et al., 2005）. Due to abundant formation of the sporangia and prolific sporulation, P. infestans can spread quickly in the host tissues and cause extensive necrosis of the infected plants （Kamoun and Smart, 2005）.

关键词： The Role of Autophagy during Development of the Oomycete Pathogen Phytophthora infestans

Centimeter-sized Ti-based bulk metallic glass with high specific strength

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Progress in Natural Science:Materials International 2012年第5期22卷 401-406页

作者： Pan Gong,Ke-fu Yao,xin wang,Yang Shao Department of Mechanical Engineering,Tsinghua University,Beijing 100084,China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Based on the quaternary Ti41Zr25Be29Al5 glassy alloy with a critical diameter of 7 mm reported not long ago,an obvious enhancement of glass-forming ability(GFA) has been realized in this alloy by the addition of Cu element.A series of(Ti41Zr25Be29Al5)100-xCux(x=0,2,5,7,9,11 at%) glassy alloys have been developed and some of them can be cast into one-centimeter diameter fully glassy rods by copper mold suction *** has been found that Cu addition could stabilize the liquid phase and suppress the crystallization,resulting in improvement of the GFA of the *** addition of Cu also increases the compressive strength of the alloy and the(Ti41Zr25Be29Al5)91Cu9 glassy alloy possesses a specific strength(defined as yield strength/density) of 4.13×105Nm/kg,which is much higher than most other reported centimeter-sized bulk metallic *** present result suggests that the newly developed(Ti41Zr25Be29Al5)91Cu9 glassy alloy is a good candidate for structural applications because of its good glass-forming ability and mechanical properties.

关键词： Metallic glasses Ti alloy Glass-forming ability Mechanical properties

Operable Breast Cancer： a Clinical Analysis of 6,263 Cases

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Chinese Journal of Clinical Oncology 2005年第5期2卷 761-766页

作者： Mingtian Yang Tiehua Rong Zhifan Huang Changuang Zeng Hao Long Jianhua fu Peng Lin xin wang Siyu wang Xi wang Jun Tang Department of Thoracic Oncology Cancer Center Sun Yat-sen UniversityGuangzhou 510060 China.

OBJECTIVE In Europe and America breast cancer commonly occurs in women of middle and old age, with a median age of about 57 years. Modified radical mastectomy now called standard radical mastectomy, has taken the place of traditional radical mastectomy. Patients with breast cancer at an early stage commonly receive BCT （breast conservative therapy）. The TNM stage （especially the lymph node status） affects the prognosis, and adjuvant therapy can improve survival. In China, only a few reports have been published studying large numbers of breast cancer patients. This study was designed to analyze the clinical features, surgical pattern and treatment outcome of resectable breast cancer, as well as to explore the prognostic factors and the effect of adjuvant therapy, with a goal to improve the level of diagnosis and treatment. METHODS Records of the 6,263 patients with resectable breast cancer who had been admitted into our hospital from June 1964 to June 2003 were analyzed retrospectively. RESULTS Of the 6,263 cases, 98.8% were female. Breast cancer occurred most frequently in patients of ages 40-49 years （41.0%）, especially in patients 45-49 years old （25.2%）. A breast lump, which occurred in 96.2% of the patients, was the main clinical manifestation. The overall 5- and 10-year survival rates were 75.16% and 40.44%. Of the patients in TNM stages 0-1, Ⅱ, and Ⅲ, the 5-year survival rates were 96.8%, 73.7% and 46.4% respectively and the 10-year survival rates were 78.7%, 64.6% and 33.5% respectively. The 5-, and 10-year survival rates were higher in the lymph node negative group than in the lymph node positive group （80.3% vs. 55.6%, and 59.2% vs. 31.9%, P〈0.01）. Since the 1980s there was no significant difference in survival rates of patients who received a radical mastectomy compared to a modified radical mastectomy（P〉0.05）. Of the 73 patients who underwent breast conservative therapy, no local recurrence or metastasis occurred during a maximal follow-up of 17 years. Of

关键词： breast neoplasms surgery adjuvant therapy prognosis.

Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu fu Lei Gu xin Shao Qinqin wang xin Dong Bin Duan Feiyang xing Jun Wu Minmin Xiao Fangqing Zhao Jing-Dong J.Han Qi Liu Xiaohui Fan Chen Li Chenfei wang Tieliu Shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening

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空间三轴机抖激光陀螺交流稳频系统设计

中国惯性技术学报 2017年第2期25卷 265-268页

作者：吴凡张明辉傅鑫郭昕王继良王京献西安飞行自动控制研究所西安710065

针对空间三轴机抖激光陀螺设计了交流稳频控制系统,分析了系统原理,进行了Simulink仿真建模和试验研究。在系统原理中分析了控制过程,推导了系统函数,通过Simulink交流稳频系统仿真建模摸索了空间三轴机抖激光陀螺交流稳频系统中PID参... 详细信息

针对空间三轴机抖激光陀螺设计了交流稳频控制系统,分析了系统原理,进行了Simulink仿真建模和试验研究。在系统原理中分析了控制过程,推导了系统函数,通过Simulink交流稳频系统仿真建模摸索了空间三轴机抖激光陀螺交流稳频系统中PID参数对系统响应的影响,并得到了优化参数(K_P=0.048,K_I=0.0021,K_D=0.0037),为硬件调试提供了参考。将交流稳频控制系统应用于国产某型空间三轴机抖激光陀螺进行试验,试验结果显示通过PID参数调节后的交流稳频陀螺PZT码值变化平稳,陀螺静态脉冲输出稳定,与原直流稳频控制方法相比将空间三轴机抖激光陀螺的精度提高了20%。

关键词：空间三轴激光陀螺交流稳频 PID参数