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THE WALL EFFECT ON VENTILATED CAVITATING FLOWS IN CLOSED CAVITATION TUNNELS

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Journal of Hydrodynamics 2008年第5期20卷 561-566页

作者： CHEN Xin LU Chuan-jing li jie PAN Zhan-cheng Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

For ventilated cavitating flows in a closed water tunnel, the wall effect may exert an important influence on cavity shape and hydrodynamics, An isotropic mixture multiphase model was established to study the wall effect based on the RANS equations, coupled with a natural cavitation model and the RNG k-ε turbulent model. The governing equations were discretized using the finite volume method and solved by the Gauss-Seidel linear equation solver on the basis of a segregation algorithm. The algebraic multigrid approach was carried through to accelerate the convergence of solution. The steady ventilated cavitating flows in water tunnels of different diameter were simulated for a conceptual underwater vehicle model which had a disk cavitator. It is found that the choked cavitation number derived is close to the approximate solution of natural cavitating flow for a 3-D disk. The critical ventilation rate falls with decreasing diameter of the water tunnel. However, the cavity size and drag coeflicient are rising with the decrease in tunnel diameter for the same ventilation rate, and the cavity size will be much different in water tunnels of different diameter even for the same ventilated cavitation number.

关键词： ventilated cavitation water tunnel choked cavitation number critical ventilation rate

Self-powered and bipolar photodetector based on a van der Waals metal-semiconductor junction: Graphene/WSe;/Fe;GeTe;heterojunction

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Science China Technological Sciences 2022年

作者： XU Guo liang liU Dan Min li jing Zhen li jing jie YE Shuai Shuai Key Laboratory of Advanced Functional Materials Ministry of Education Faculty of Materials and Manufacturing Beijing University of Technology Key Laboratory of Optoelectronics Technology College of Microelectronics Faculty of Information Technology Beijing University of Technology

A self-driven photosensor with signal-reversal response has the potential to work as a photodetector in complex environments with multiple signals owing to better signal recognition and enhanced signal-processing efficiency. Herein, a metal-semiconductor-metal photodetector based on ambipolar WSe;with two electrodes comprising two-dimensional（2D） van der Waals（vd Ws） metal Fe;GeTe;and semimetal graphene was proposed to form an asymmetrical metal-contacted architecture with different Schottky barrier heights. The regulating gate field-induced Fermi level shift in WSe;can be used to manipulate the WSe;channel’s carrier type, resulting in a polarity-reversible photodetector without a bias voltage. Furthermore, the photovoltaic effect can be observed from wavelengths of 450 nm（visible） to 850 nm（infrared） without external voltage. The large open voltage is-0.177 V and short-circuit current is 17 n A under a 650-nm excitation wavelength. The reported WSe;-based photodetector exhibits excellent properties under zero bias, including a large photo-to-dark current ratio greater than 106 with dark current less than 1 f A, photovoltaic performance with an external quantum efficiency of 27.14%, an excellent detectivity of 3.4×1010Jones, and a high responsivity of 116.38 m A/W. Rapid electron transfer occurs at the interface between WSe;and vd Ws electrodes, resulting in a 370-μs response speed owing to the clean and nondestructive interfaces between vd Ws metals and WSe;. This study demonstrates the wide application prospect of the vd Ws metal Fe;GeTe;as an electrode forming a Schottky junction for realizing a photodetector without an external voltage and accelerates the development of 2D photosensors with various working modes.

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RESEARCH ON HYDRODYNAMIC FORCES OF CAVITATING GRID FINS

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Journal of Hydrodynamics 2005年第2期17卷 148-153页

作者： FUHui-ping LUChuan-jing lijie WULei SchoolofNavalArchitecture OceanandCivilEngineeringShanghaiJiaotongUniversityShanghai200030China

Hydrodynamic forces and flow pattern of four kinds of cavitating grid fins with cavitation number from 2.5 to 0.25 were simulated numerically with a bubble two-phase flow model embodied in the commercial CFD code Fluent 6.0. Comparison with experimental datum showed that rules of hydrodynamic forces changing with cavitation number were coordinated with experiment, and cavitation made the ratio of lift to resistance decrease. Calculated axial force and chordal pressure center in all-wetted condition or those at cavitation number less than 0.75 agreed well with experiments. Normal force in all-wetted condition was less by 20 per cent. The differences between computation and experiment in the total range of cavitation number were mainly because that the incipient cavitation number in computation was less than that at experiment.

关键词： grid fin cavitation hydrodynamic force

A Positive Comparative Study of Regional Human Resources Quality

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Systems Science and Systems Engineering 2000年第2期10卷 185-193页

作者： YUAN li\|jing,\ li Jun\|jie College of Management, Zhejiang University, Hangzhou 310027, China

This thesis appraises the human resources in developed regions, relatively developed regions, moderately developed regions and underdeveloped regions in China by means of comprehensive fuzzy assessment of human resources quality. Then the interrelationship between regional economic development and human resources quality is analysed. The results can be of some value for decision making.

关键词： regional human resources quality economic development/growth comparative research

Mean-square Exponential Robust Stability for a Class of Grey Stochastic Systems with Distributed Delays

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Chinese Quarterly Journal of Mathematics 2010年第3期25卷 451-458页

作者： li jing-jie SU Chun-hua College of Mathematics and Information Science Xinyang Normal University Xinyang 464000 China

Two easily verified delay-dependent criteria of mean-square exponential robust stability are obtained by constructing Lyapunov-Krasovskii functional and employing the decomposition technique of the continuous matrix-discovered set of grey matrix and Ito formula.A numerical example shows the validity and practicality of the criteria presented in this paper.

关键词： stochastic systems distributed delays Lyapunov-Krasovskii functional robust stability grey matrix

Expression of PIN Genes in Rice （Oryza sativa L.）： Tissue Specificity and Regulation by Hormones

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Molecular Plant 2009年第4期2卷 823-831页

作者： Ji-Rong Wang Han Hu Gao-Hang Wang jing li jie-Yu Chen Ping Wu State Key Laboratory of Plant Physiology and Biochemistry College of Life Sciences Zi Jin Gang Campus Zhejiang University Hangzhou 310058 People's Republic of China

Twelve genes of the PIN family in rice were analyzed for gene and protein structures and an evolutionary relationship with reported AtPINs in Arabidopsis. Four members of PIN1 （designated as OsPINla-d）, one gene paired with AtPIN2 （OsPIN2）, three members of PIN5 （OsPIN5a-c）, one gene paired with AtPIN8 （OsPIN8）, and three monocot-specific PINs （OsPIN9, OsPINIOa, and b） were identified from the phylogenetic analysis. Tissue-specific expression patterns of nine PIN genes among them were investigated using RT-PCR and GUS reporter. The wide variations in the expression domain in different tissues of the PIN genes were observed. In general, PIN genes are up-regulated by exogenous auxin, while different responses of different PIN genes to other hormones were found.

关键词： Oryza sativa L. PIN family expression pattern.

Clinicopathological Features and Long-Term Prognostic Role of Human Epidermal Growth Factor Receptor-2 Low Expression in Chinese Patients with Early Breast Cancer:A Single-Institution Study

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Biomedical and Environmental Sciences 2024年第5期37卷 457-470页

作者： KONG Zi Qing liU li Qun HUANG De Qin WANG Yu Tong li jing jie ZHANG Zheng WANG Xi Xi liU Chuan ling ZHANG Ya Di SHAO Jia Kang ZHU Yi Min CHEN Yi Meng liU Mei ZHAO Wei Hong Medical School of Chinese PLA Beijing 100853China Department of Medical Oncology the First Medical CenterGeneral Hospital of the Chinese People’s Liberation ArmyBeijing 100853China Nankai University School of Medicine Tianjin 300071China Department of Medical Oncology the Fifth Medical CenterGeneral Hospital of the Chinese People’s Liberation ArmyBeijing 100039China Department of Medical Oncology Xi'an Jiaotong UniversityXi’an 710061ShaanxiChina Department of Pathology the Sixth Medical CenterGeneral Hospital of the Chinese People’s Liberation ArmyBeijing 100037China

Objective This study aimed to comprehensively analyze and compare the clinicopathological features and prognosis of Chinese patients with human epidermal growth factor receptor 2(HER2)-low early breast cancer(BC)and HER2-IHC0 *** Patients diagnosed with HER2-negative BC(N=999)at our institution between January2011 and December 2015 formed our study *** characteristics,association between estrogen receptor(ER)expression and HER2-low,and evolution of HER2 immunohistochemical(IHC)score were ***-Meier method and log-rank test were used to compare the long-term survival outcomes(5-year follow-up)between the HER2-IHC0 and HER2-low *** HER2-low BC group tended to demonstrate high expression of ER and more progesterone receptor(PgR)positivity than HER2-IHC0 BC group(Plinicopathological features and prognostic roles.

关键词： HER2 HER2-low Breast cancer Estrogen receptor Trastuzumab deruxtecan

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青州风格佛教造像的形成与发展

敦煌研究 2007年第2期 6-13,118,119,120页

作者：李静杰清华大学美术学院北京100096

此稿着重分析了泰安北魏太和十八年金铜佛像在青州风格佛教造像形成过程中的位置和作用。之后,讨论了典型青州风格形成时期,广义青州西部、中部和东部地区的佛教造像,以及青州地区继续吸收外部因素,和青州风格对外部的影响情况。

关键词：佛教造像青州风格

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以核受体为靶标的胆汁淤积治疗药物研究进展

中国药理学通报 2015年第9期31卷 1195-1198页

作者：陈攀李晶洁陈杰中山大学附属第一医院药学部临床药学室广东广州510080 中山大学附属第六医院广东广州510655

胆汁淤积的治疗药物匮乏,熊去氧胆酸是目前唯一被FDA通过的治疗原发性胆汁性肝硬化的药物,但其药效却限于疾病早期,因此迫切需要开发新的胆汁淤积治疗药物。核受体能调控胆汁酸稳态,它作为胆汁淤积治疗的靶标是目前研究的热点。该综述... 详细信息

胆汁淤积的治疗药物匮乏,熊去氧胆酸是目前唯一被FDA通过的治疗原发性胆汁性肝硬化的药物,但其药效却限于疾病早期,因此迫切需要开发新的胆汁淤积治疗药物。核受体能调控胆汁酸稳态,它作为胆汁淤积治疗的靶标是目前研究的热点。该综述对目前报道最多的核受体进行总结,分析其作为胆汁淤积药物治疗靶标的利弊及应用前景。

关键词：胆汁淤积法尼酯X受体孕烷X受体组成性雄烷受体 1,25-二羟基维生素D3受体糖皮激素受体肝脏X受体过氧化物酶体增殖物活化受体转录因子-E2-相关因子2