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Experimental investigation on the distribution uniformity and pressure drop of perforated plate distributors for the innovative spray-type packed bed thermal storage

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Particuology 2022年第2期20卷 60-73页

作者： lin lin Liang Wang Xipeng lin Ningning xie Haisheng Chen Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China National Energy Large Scale Physical Energy Storage Technologies R&D Center of Bijie High-tech Industrial Development Zone Guizhou 551712China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China

As an innovative thermal energy technology,the spray-type packed bed has advantages of high efficiency and low cost.A liquid distributor is the key component for the spray-type packed bed for scattering heat-transfer liquid drops *** this study,the distribution performance and pressure drop of the perforated plate distributors of different orifice diameters were studied *** experimental results indicate that orifice diameter has a greater effect on the distribution performance compared to flow *** an increase in flow rate,the flow pattern through the distributor changes from the uncovered drop to the covered drop and then to the jet *** covered drop pattern shows the best performance with a good distribution and a small pressure drop simultaneously,which is the design and optimization principle of the distributor for a spray-type packed bed.

关键词： Spray-type packed bed Perforated plate distributor Distribution Pressure drop Thermal energy storage

Microstructure and mechanical properties of BFe10 cupronickel alloy tubes fabricated by a horizontal continuous casting with heating-cooling combined mold technology

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International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 339-347页

作者： Jun mei Xin-hua Liu Jian-xin xie Key Laboratory for Advanced Materials Processing (Ministry of Education) University of Science and Technology Beijing Beijing 100083 China Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China

A new horizontal continuous casting method with heating-cooling combined mold （HCCM） technology was explored for fabri- cating high-quality thin-wall cupronickel alloy tubes used for heat exchange pipes. The microstructure and mechanical properties of BFe 10 cupronickel alloy tubes fabricated by HCCM and traditional continuous casting （cooling mold casting） were comparatively investigated. The results show that the tube fabricated by HCCM has smooth internal and external surfaces without any defects, and its internal and external surface roughnesses are 0.64 μm and 0.85 μm, respectively. The tube could be used for subsequent cold processing without other treatments such as surface planning, milling and acid-washing. This indicates that HCCM can effectively reduce the process flow and improve the pro- duction efficiency of a BFel0 cupronickel alloy tube. The tube has columnar grains along its axial direction with a major casting texture of {012}〈 621 〉. Compared with cooling mold casting （6 = 36.5%）, HCCM can improve elongation （3 = 46.3%） by 10% with a slight loss of strength, which indicates that HCCM remarkably improves the cold extension performance of a BFe 10 cupronickel alloy tube.

关键词： cupronickel alloys thin-wall tubes continuous casting microstructure mechanical properties

Event-triggered Tracking Consensus with Packet Losses and Time-varying Delays

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IEEE/CAA Journal of Automatica Sinica 2016年第2期3卷 165-173页

作者： mei Yu Chuan Yan Dongmei xie Guangming xie the Department of Control and Computer Engineering North China Electric Power University the Department of Mathematics School of Sciences Tianjin University the Department of Engineering Peking University

This paper mainly investigates the event-triggered tracking control for leader-follower multi-agent systems with the problems of packet losses and time-varying delays when both the first-order and the second-order neighbors' information are used. Event-triggered control laws are adopted to reduce the frequency of individual actuation updating under the sampleddata framework for discrete-time agent dynamics. The communication graph is undirected and the loss of data across each communication link occurs at certain probability, which is governed by a Bernoulli process. One numerical example is given to demonstrate the effectiveness of the proposed methods. It is found that the tracking consensus is sped up by using the second-order neighbors' information when packet losses and time-varying delays occur. © 2014 Chinese Association of Automation.

关键词： Multi agent systems Numerical methods Packet loss Time delay

Protective effects of proanthocyanidins on beta-amyloid peptide (25-35)-induced PC12 cell apoptosis by blocking S-phase and increasing p53 gene expression

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Neural Regeneration Research 2010年第2期5卷 108-112页

作者： Hanfang mei Zhaoyang xie Qifeng Zhu Department of Biochemistry and Molecular Biology Guangdong Pharmaceutical University Guangzhou 510006 Guangdong Province China School of Pubfic Health and Tropical Medicine Southem Medical University Guangzhou 510515 Guangdong Province China Institute of Biochemistry and Molecular Biology Guangdong Medical College Zhanjiang 524023 Guangdong Province China

BACKGROUND： Current studies related to the effects of proanthocyanidins on Alzheimer＇s disease have focused primarily on the signal transduction pathway of cellular apoptosis. However, the influence of p53 gene expression on cell cycle regulation, with regard to the protective mechanisms of proanthocyanidins, has not been reported. OBJECTIVE： To observe the effect of proanthocyanidins on cell cycle distribution, cellular apoptosis and p53 gene expression in β-amyloid peptide （25-35）（Aβ25-35）-induced PC12 cells cultured in serum-free media, and to investigate the molecular neuroprotective mechanisms of proanthocyanidins with regard to cell cycle regulation. DESIGN, TIME AND SETTING： A parallel, controlled, at the Institute of Biochemistry and Molecular Biology cellular, and molecular study was performed Guangdong Medical College from July 2006 to July 2008. MATERIALS： Proanthocyanidins were provided by Nanjing Xuezi Medical and Chemical Research Center, China; Aβ25-35 was provided by Sigma, USA; PC12 cells were provided by the Institute of Basic Medical Science, Academy of Military Medical Sciences; and rabbit anti-p53 polyclonal antibody was provided by Santa Cruz Biotechnology, USA. METHODS： PC12 cells were cultured in serum-free media for 24 hours. Cells from the model group were treated with 25 μmol/L Aβ25-35 for 24 hours. Cells in the drug protection group were pre-treated with 30 mg/L proanthocyanidins for 1 hour and then treated with 25 μmol/LAβ2^-35 for 24 hours. The control group was not treated. MAIN OUTCOME MEASURES： Flow cytometry was used to detect cell cycle distribution and rate of apoptosis; reverse-transcriptase polymerase chain reaction was used to detect p53 mRNA expression; and Western blot was used to detect p53 protein expression. RESULTS： After treating with 25 μmol/LAβ25-35 for 24 hours, the rate of apoptosis and the percentage of cells in S phase were significantly increased （P 〈 0.01 ）, and p53 mRNA and protein expressions were decreased. P

关键词： proanthocyanidins β-amyloid peptide (25-35) Alzheimer's disease PC12 cells p53 gene neural regeneration

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眼科新进展 2025年第1期45卷 33-38页

作者：谢婧王正静杨梅胡红芳冯亮赵粟贵州医科大学贵州省贵阳市550004 贵州医科大学附属医院眼科贵州省贵阳市550004 贵阳爱尔眼科医院贵州省贵阳市550005

目的分析1990~2021年中国年龄相关性黄斑变性(AMD)疾病负担变化趋势及年龄、时期和队列效应产生的影响,预测2022~2035年中国AMD患者的标化患病率和标化伤残调整寿命年(DALYs)的DALY率。方法从2021年全球疾病负担数据库中获取1990~2021... 详细信息

目的分析1990~2021年中国年龄相关性黄斑变性(AMD)疾病负担变化趋势及年龄、时期和队列效应产生的影响,预测2022~2035年中国AMD患者的标化患病率和标化伤残调整寿命年(DALYs)的DALY率。方法从2021年全球疾病负担数据库中获取1990~2021年中国AMD患病率、患病人数、DALYs和DALY率数据,采用分段回归模型分析中国AMD患者患病和DALYs的趋势变化,运用年龄-时期-队列(APC)模型估算AMD患病风险和DALY风险的年龄、时期和队列效应,并使用贝叶斯年龄-时期-队列模型预测2022~2035年中国AMD的标化患病率和标化DALY率。结果2021年中国AMD患病人数和患病率较1990年分别升高199.94%和148.02%,2021年DALYs和DALY率较1990年分别升高183.95%和134.80%,其中女性的相关指标均高于男性。1990~2021年AMD标化患病率呈现上升趋势,平均年度变化百分比(AAPC)为0.17%。AMD标化DALY率呈现下降趋势,AAPC为-0.03%。APC模型结果显示,中国AMD患病率和DALY率的纵向年龄曲线呈先上升后下降的趋势,在85~89岁时达高峰。随着时期的推移,AMD的患病风险呈先上升后下降的趋势,DALY风险随时期的增加呈下降趋势。出生队列结果显示,我国AMD患病风险队列效应整体波动不大,呈现先下降后波动式上升的趋势,DALY风险则随着出生队列时间的后移逐渐降低。预测2022~2035年中国AMD的标化患病率和标化DALY率均呈现上升趋势。结论1990~2021年中国AMD的标化患病率呈上升趋势,标化DALY率呈下降趋势,并且女性群体疾病负担高于男性,随着人口老龄化的加剧,预测2022~2035年中国AMD的标化患病率和标化DALY率仍将持续上升,根据我国人群AMD患病和DALYs的相关特点,提示有关部门应重视对老年女性群体的干预,同时应加强对全人群的健康科普教育并制定有效的公共卫生预防政策,以期降低我国AMD造成的重大疾病负担。

关键词：年龄相关性黄斑变性全球疾病负担患病率伤残调整寿命年分段回归模型年龄-时期-队列模型

Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States

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China Ocean Engineering 2018年第6期32卷 683-695页

作者： WU lin-jian WANG Yuan-zhan WANG Yu-chi CHEN Jia-yu LI Yi LI Qing-mei xie Tao State Key Laboratory of Hydraulic Engineering Simulation and Safety Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationTianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China College of Engineering Ocean University of ChinaQingdao 266100China Chongqing Shipping Engineering Survey and Design Institute of the Yangtze River Chongqing 401147China School of River&Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China

This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was used as a case study. Numerous constraint forces and relative displacements for the connectors at rough sea states with different wave angles were utilized to determine the optimized stiffness of the flexible connectors. The range of optimal stiffnesses for the connectors was obtained based on the combination and intersection of the optimized stiffness results, and the implementation steps were elaborated in detail. The percentage reductions of the optimized and optimal stiffness of the flexible connector were determined to quantitatively evaluate the decreases of the constraint force and relative displacement of the connectors compared with those calculated by using the original range of the connector stiffnesses. The results indicate the accuracy and feasibility of this method for determining the optimal stiffness of the flexible connectors and demonstrate the rationality and practicability of the optimal stiffness results. The research ideas, calculation process, and solutions for the optimal stiffness of the flexible connectors of an MOB in this paper can provide valuable technical support for the design of the connectors in similar semisubmersible floating structures.

关键词： mobile offshore base(MOB) flexible connectors the optimal stiffness rough sea states

2D free-standing ultra-large ferromagnetic nanosheets via a topotactic transformation strategy

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Science China Chemistry 2025年

作者： Haofeng Sun Minghao Wang Wenjie Li Yang Liu Xinyu Sun Wenjie Wang Yuqiao Guo Yi xie Changzheng Wu Key Laboratory of Precision and Intelligent Chemistry University of Science&Technology of China National Synchrotron Radiation Laboratory University of Science and Technology of China

Considerable progress has been made in synthesizing two-dimensional （2D） materials by exfoliating layered ***,for tremendous non-layered inorganic materials,especially magnet solids,usually with closely packed bulk phases by strong chemical bonds,it is challenging to obtain their high-quality 2D ***,we highlighted a new structure of free-standing ferromagnetic nanosheets featuring （111） *** magnet,Fe3O4,its inversed spinel crystalline has limited abilities to exfoliate into 2D forms and rarely exists as free-standing nanosheets owing to aggregation induced by magnetic *** realized a breakthrough in achieving free-standing ferromagnetic nanosheets with dramatically surpassing size limitations via topotactic conversion from layered *** Fe3O4nanosheets exhibited a maximum width of 60μm while only～4 nm thick,prominently exposing （111） facets.2D Fe3O4behaved anisotropic magnetism,which displayed a 4.6 emu g-1moment（H=500 Oe） in the （111） plane but 2.1 emu g-1out of the （111） plane,indicating a （111） in-plane easy *** anticipated our topotactic conversion strategy would inspire the creation of 2D non-layered materials and enrich the 2D materials family.

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Non-linear Viscoelastic Rheological Properties of PCC/PEG Suspensions

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Chinese Journal of Chemical Physics 2009年第1期22卷 46-50页

作者： Hai-lin Yang Jian-ming Ruan Jian-peng Zou Qiu-mei Wu Zhong-cheng Zhou Yuan-yan xie State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

The shear thinning and shear thickening rheological properties of PCC/PEG suspension were investigated with the increase of oscillatory amplitude stress at different constant frequencies. The results show that the complex viscosity was initially independent of stress amplitude and obvious shear thinning occurred, then dramatic shear thickening took place after reaching the minimum viscosity. Typically, in a constant frequency of 5 rad/s, the elastic modulus, viscous modulus, and tanδ （δ is the out-of-phase angle） vs. the stress amplitude was investigated. It is found that the elastic modulus initially appeared to be independent of stress amplitude and then exhibited a rapid decrease, but the viscous modulus was independent of amplitude stress at lower amplitude stress. After reaching the minimum value the viscous modulus showed a rapid increase. On the other hand, tanδ increased from 0.6 to 92, which indicates that the transition from elastic to viscous had taken place and tanδ showed a steep increase when shear thickening occurred. Lissajous plots are shown for the dissipated energy vs. different maximum stress amplitude in the shear thinning and shear thickening regions. The relationship of dissipated energy vs. maximum stress amplitude was determined, which follows a power law. In the shear thinning region the exponent was 1.91, but it steeply increases to 3.97 in the shear thickening region.

关键词： Precipitated calcium carbonate Suspension Shear thickening Dynamic oscillatory shear Rheological response

New coordination scheme for multi-robot systems based on state space models

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Journal of Systems Engineering and Electronics 2008年第4期19卷 722-734页

作者： xie Wenlong Su Jianbo lin Zongli Dept. of Automation Shanghai Jiaotong Univ. Shanghai 200240 P. R. China Charles L. Brown Dept. of Electrical and Computer Engineering Univ of Virginia Charlottesville VA 22904-4743 USA

A new coordination scheme for multi-robot systems is proposed. A state space model of the multi- robot system is defined and constructed in which the system＇s initial and goal states are included along with the task definition and the system＇s internal and external constraints. Task accomplishment is considered a transition of the system state in its state space （SS） under the system＇s constraints. Therefore, if there exists a connectable path within reachable area of the SS from the initial state to the goal state, the task is realizable. The optimal strategy for the task realization under constraints is investigated and reached by searching for the optimal state transition trajectory of the robot system in the SS. Moreover, if there is no connectable path, which means the task cannot be performed Successfully, the task could be transformed to be realizable by making the initial state and the goal state connectable and finding a path connecting them in the system＇s SS. This might be done via adjusting the system＇s configuration and/or task constraints. Experiments of multi-robot formation control with obstacles in the environment are conducted and simulation results show the validity of the proposed method.

关键词： multi-robot system coordination state space formation maneuver subgoal