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Tomographic particle image velocimetry measurement on three-dimensional swirling flow in dual-stage counter-rotating swirler

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Chinese Journal of Aeronautics 2024年第3期37卷 7-20页

作者： Yuyang zhou ling DONG Mingtao SHANG Jibao li Akira RINOSHIKA Key Laboratory of Fluid Mechanics of Ministry of Education Beihang UniversityBeijing 100191China School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China Department of Mechanical Systems Engineering Yamagata UniversityYamagata 992-8510Japan

Three-Dimensional(3D)swirling flow structures,generated by a counter-rotating dualstage swirler in a confined chamber with a confinement ratio of 1.53,were experimentally investigated at Re=2.3×10^(5)using Tomographic Particle Image Velocimetry(Tomo-PIV)and planar Particle Image Velocimetry(PIV).Based on the analysis of the 3D time-averaged swirling flow structures and 3D Proper Orthogonal Decomposition(POD)of the Tomo-PIV data,typical coherent flow structures,including the Corner Recirculation Zone(CRZ),Central Recirculation Zone(CTRZ),and lip Recirculation Zone(LRZ),were *** counter-rotating dual-stage swirler with a Venturi flare generates the independence process of vortex breakdown from the main stage and pilot stage,leading to the formation of an LRZ and a smaller CTRZ near the nozzle *** confinement squeezes the CRZ to the corner and causes a reverse rotation flow to limit the shape of the CTRZ.A large-scale flow structure caused by the main stage features an explosive breakup,flapping,and Precessing Vortex Core(PVC).The explosive breakup mode dominates the swirling flow structures owing to the expansion and construction of the main jet,whereas the flapping mode is related to the wake *** limits the expansion of PVC and causes it to contract after the impacting area.

关键词： Coherent structures Dual-stage counter-rotating swirler cup Precessing vortex core Proper orthogonal decomposition Swirling flow Tomographic particle image velocimetry

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Mechanism of multidrug resistance of human small cell lung cancer cell line H446/VP

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Chinese Medical Journal 2010年第22期123卷 3299-3303页

作者： WANG Yan-ling YAN Yun-li zhou Na-jing HAN Shuo ZHAO Jun-xia CAO Cui-li LUE Yu-hong Cell Biology Division Institute of Basic Medicine Hebei Medical University Shijiazhuang Hebei 050017 China

Background Small cell lung cancer （SCLC） is the most aggressive form of lung cancer. This study aimed to investigate the mechanism of human small cell lung cancer cell line resistance to etoposide （VP-16）, H446NP. Methods The cell viability was measured by MTT assay. Immunocytochemistry, reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting methods were used to detect the multidrug resistance gene （MDR1）, bcl-2, bax and the topoisomerase Ⅱ （TopoⅡ） expressions in H446 and H446NP cells after treated with or without VP-16. Results The 50% inhibition concentration （IC50） of VP-16 on H446 cells was 49 mg/L, and 836 mg/L was for H446NP cells. The expressions of MDR1 and bcl-2 were up-regulated, while the amounts of bax and Topo II were reduced in H446NP cells. After treated with 49 mg/L of VP-16, it showed that the drug could significantly inhibit bcl-2 and Topo fl expressions, and increase bax expression in H446 cells compared with that of H446NP cells. Conclusions The H446NP cell was stably resistant to VP-16. The decreased expression of Topo II was correlated with the H446NP multidrug resistance. The elevated expressions of MDR1, and the altered apoptotic pathways also played an important role in VP-16 induced multidrug resistance of SCLC.

关键词： small cell lung cancer etoposide topoisomerase II, multidrug resistance

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Fabrication and Microstructure of W/Cu Functionally Graded Material

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Journal of University of Science and Technology Beijing 2001年第3期8卷 198-202页

作者： Yunhan ling, Jiangtao li, Zhangjian zhou, Changchun Ge Laboratory of Special Ceramics & Powder Metallurgy, University of Science and Technology Beijing, Beijing 100083, China Lab. of Spec. Ceram. and Powd. Meta. Univ. of Sci. and Technol. Beijing Beijing 100083 China

W/Cu functionally gradient material (FGM) has excellent mechanical properties since it can effectively relax interlayer thermal stresses caused by the mismatch between their thermal expansion coefficients. W/Cu FGM combines the advantages of tungsten such as high melting point and service strength, with heat conductivity and plasticity of copper at room temperature. Thus it demonstrates satisfactory heat corrosion and thermal shock resistance and will be a promising candidate as divertor component in thermonuclear device. Owing to the dramatic difference of melting point between tungsten and copper, conventional processes meet great difficulties in fabricating this kind of FGMs. A new approach termed graded sintering under ultra-high pressure (GSUHP) is proposed, with which a near 96% relative density of W/Cu FGM that contains a full distribution spectrum (0-100%W) has been successfully fabricated. Suitable amount of transition metals (such as nickel, zirconium, vanadium) is employed as additives to activate tungsten's sintering, enhance phase wettability and bonding strength between W and Cu. Densification effects of different layer of FGM were investigated. Microstructure morphology and interface elements distribution were observed and analyzed. The thermal shock performance of W/Cu FGM was also preliminarily tested.

关键词： tungsten copper sintering functionally graded material composite

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Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： Rui Wang Zhiming zhou Kaiwen li Tao Zhang ling Wang Xin Xu Xiangke liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning

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A Screening Approach for Mitochondrial tRNALeu（UUR） A3243G Mutation in a Hospital-Based Population with Diabetes

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Chinese Medical Journal 2018年第9期131卷 1117-1119页

作者： li-Hua Tian Xue-Yao Han Xiu-Ting Huang Si-Min Zhang Si-Qian Gong Yu-Min Ma Xiao-ling Cai ling-li zhou Ying-Ying Luo Meng li Wei liu Xiu-Ying Zhang Qian Ren Yu Zhu Xiang-Hai zhou Rui Zhang ling Chen Xue-Ying Gao Yan liu Fang Zhang li-Nong Ji Department of Endocrinology and Metabolism Peking University People's Hospital Peking University Diabetes Center Beijing 100044 China

To the Editor：Diabetes caused by mitochondrial tRNALeu（UUR） A3243G mutation is one of the most common types ofmitochondrial diabetes mellitus （MDM）.Seventeen years ago,we reported that the prevalence of MDM was 0.4％ in clinically diagnosed type 2 diabetes mellitus （T2DM） patients （n =716）.[1] Recently,we reviewed all the studies reporting MDM cases from grade three and first-class hospitals in China （unpublished） and found that the prevalence of MDM in a pooled randomly selected T2DM population was 0.64％.MDM patients are usually characterized by early age at diagnosis,low beta-cell function,and lack of obesity,insulin resistance,and autoantibodies associated with type 1 diabetes mellitus （T1DM）.

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A mixed-valence polyoxometalate-based 3D inorganic framework cathode material for high-efficiency rechargeable AZIBs

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Rare Metals 2024年第8期43卷 3677-3691页

作者： Qing Han Hao-Ran Xiao Tao zhou Bing-Chuan li liu Yang ling-ling Xie Xue-Jing Qiu Xian-Yong Wu li-Min Zhu Xiao-Yu Cao School of Chemistry and Chemical Engineering Henan University of TechnologyZhengzhou 450001China Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City Zhengzhou 450001China College of Materials Engineering Henan University of EngineeringZhengzhou450007China School of Environmental Engineering Henan University of TechnologyZhengzhou 450001China Department of Chemistry University of Puerto Rico-Rio Piedras CampusSan JuanPR 00925USA

The global trend towards new energy storage systems has stimulated the development of electrochemical energy storage *** these technologies,rechargeable aqueous zinc-ion batteries(AZIBs)have attracted considerable interest as a potential alternative to lithium-ion batteries(liBs)due to their affordable cost,environmental compatibility and high safety *** this study,a high-quality electrode for AZIBs has been successfully developed using a dehydrated mixed-valence polyoxometalate-based three-dimensional(3D)inorganic framework material known as[H_6Mn_(3)V^Ⅳ_(15)V-^Ⅴ_(4O)_(46)(H_2O)_(12)](3D-MnVO).This innovative 3D-MnVO material is built from the alternate connections of{V_(19)O_(46)}"sphere-shaped"clusters andμ_(2)-{Mn(H_(2)O)_(4)}bridges,where each{V_(19)O_(46)}cluster is surrounded by three pairs of vertically distributed{Mn(H_(2)O)_(4)}units,thus resulting in the 3D interpenetrating grid-like network from the infinite[-{V_(19)O_(46)}-μ_(2)-Mn(H_(2)O)_(4)-{V_(19)O_(46)}]_∞chains in three mutually perpendicular *** 3D framework structure of 3D-MnVO possesses abundant oxygen vacancies,spacious and multi-level interconnected channels for ion transport,which facilitates the efficient intercalation/deintercalation of hydrated Zn^(2+)into the pores of the primary structure via the intercalation capacitance *** a result,the 3D-MnVO electrode exhibits excellent diffusion rates and minimal interfacial *** a current density of 0.1 A·g^(-1),the 3D-MnVO cathode delivers a commendable discharge capacity of170.5 mAh·g^(-1)with 81.6%capacity retention after100 charge/discharge ***,even at a high current density of 1.0 A·g^(-1),the 3D-MnVO electrode delivers a remarkable reversible capacity of198.9 mAh·g^(-1).Our research results provide valuable insights into the development of advanced polyoxometalate-based 3D inorganic framework electrode materials for high-performance rechargeable AZIBs.

关键词： Cathode Polyoxometalate 3D inorganic framework Zinc-ion batteries Energy storage mechanism

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Multi-performance evaluation of high-throughput accelerated corrosion test for high-strength low-alloy 921A steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1260-1278页

作者： Cong-cong Du Ming-hua Qin Zhan-fang Wu Dong-ling li Lei Zhao Xiang-yang li Hai-zhou Wang Beijing Advanced Innovation Center for Materials Genome Engineering National Center for Materials Service SafetyUniversity of Science and Technology BeijingBeijing100083China China Iron and Steel Research Institute Group Co. Ltd.Beijing100081China Beijing Advanced Innovation Center for Materials Genome Engineering Central Iron and Steel Research InstituteBeijing100081China

The corrosion behavior of high-strength low-alloy 921A steel in a simulated marine atmospheric environment was studied using a high-throughput experimental *** corrosion behavior,corrosion morphology,and corrosion products of 921A steels were analyzed using various techniques,including corrosion mass loss method,polarization curve,white-light interferometry,scanning electron microscopy,energy-dispersive spectrometry,microbeam X-ray fluorescence spectrometry,X-ray diffraction technique,and X-ray photoelectron *** test results indicated that 921A steel exhibits better corrosion resistance than Q450NQR1 steel in simulated harsh atmospheric environments,as evidenced by a lower corrosion mass loss rate throughout the corrosion *** corrosion products of both steels consisted ofα-FeOOH,Fe_(3)O_(4),andγ-FeOOH,withα-FeOOH being more prevalent in the rust layer of 921A steel than in Q450NQR1 *** inner rust layer of 921A steel also exhibited an appositional enrichment region of Cr,Ni,Mo,and V,leading to its superior corrosion resistance compared to that of Q450NQR1 *** efficacy of high-throughput accelerated corrosion experimental methods was highlighted for evaluating the corrosion resistance of steel materials in harsh environmental *** findings suggest that 921A steel exhibits better corrosion resistance compared to Q450NQR1 steel and has the potential to be more suitable in harsh marine atmospheric *** characterization of the rust layer structures and composition reveals the parallel enrichment of certain elements in the inner rust layer of 921A steel,which enhances its corrosion resistance.

关键词： Atmospheric corrosion High-throughput experimental method High-strength low-alloy steel Corrosion characteristics Rust layer Element enrichment

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Critical Metals Ga,Ge and In in the Global Pb-Zn Deposits:Current Understanding,Challenges and Perspectives

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Journal of Earth Science 2023年第4期34卷 1308-1311页

作者： Yi Zheng Peng-Peng Yu Zhan-Ke li Suo-Fei Xiong ling-li zhou Jia-Xi zhou ChangMing Wang Yu-Miao Meng Yu Zhang Ye-Jian Wang Jing Xu Yue Wu Lan-Xuan Guo Taiping Zhao Guangdong Provincial Key Lab of Geological Process and Mineral Resources Survey School of Earth Sciences and Geological EngineeringSun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Geological Processes and Mineral Resources School of Earth ResourcesChina University of GeosciencesWuhan 430074China Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of GeosciencesWuhan 430074China Department of Earth Sciences Vrije Universiteit Amsterdam de Boelelaan 1085Amsterdam 1081HVNetherlands Key Laboratory of Critical Minerals Metallogeny in Universities of Yunnan Province School of Earth SciencesYunnan UniversityKunming 650500China State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of ScienceGuiyang 550081China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring School of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China Key Laboratory of Exploration Technologies for Oil and Gas Resources Key Laboratory of Petroleum Geochemistry and EnvironmentYangtze UniversityWuhan 430100China Zhongjin lingnan Nonfemetal Co. LtdShenzhen 518000China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

BACKGROUND A spectrum of strategically critical metals, such as gallium(Ga), germanium(Ge) and indium(In), with promising applications in green and high-tech fields, are produced as byproducts of zinc ores in a variet... 详细信息

关键词： magmatic hydrothermal porphyry

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Minocycline in the eradication of Helicobacter pylori infection: A systematic review and meta-analysis

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World Journal of Gastroenterology 2024年第17期30卷 2354-2368页

作者： Kai zhou Cai-ling li Hua Zhang Bao-Jun Suo Yu-Xin Zhang Xin-Lu Ren Yu-Xin Wang Chang-Min Mi ling-ling Ma li-Ya zhou Xue-li Tian Zhi-Qiang Song Department of Gastroenterology Peking University Third HospitalBeijing 100191China

BACKGROUND Difficulty in obtaining tetracycline,increased adverse reactions,and relatively complicated medication methods have limited the clinical application of the classic bismuth quadruple ***,the search for new alternative drugs has become one of the research *** recent years,minocycline,as a semisynthetic tetracycline,has demonstrated good potential for eradicating Helicobacter pylori(***)infection,but the systematic evaluation of its role remains *** To explore the efficacy,safety,and compliance of minocycline in eradicating *** *** We comprehensively retrieved the electronic databases of PubMed,Embase,Web of Science,China National Knowledge Infrastructure,SinoMed,and Wanfang database as of October 30,2023,and finally included 22 research reports on *** eradication with minocycline-containing regimens as per the inclusion and exclusion *** eradication rates of *** were calculated using a fixed or a random effect model,and the heterogeneity and publication bias of the studies were *** The single-arm meta-analysis revealed that the minocycline-containing regimens achieved good overall *** eradication rates,reaching 82.3%[95%confidence interval(CI):79.7%-85.1%]in the intention-to-treat analysis and 90.0%(95%CI:87.7%-92.4%)in the per-protocol *** overall safety and compliance of the minocycline-containing regimens were good,demonstrating an overall incidence of adverse reactions of 36.5%(95%CI:31.5%-42.2%).Further by traditional meta-analysis,the results showed that the minocycline-containing regimens were not statistically different from other commonly used eradication regimens in eradication rate and incidence of adverse *** of the adverse reactions were mild to moderate and well-tolerated,and dizziness was relatively prominent in the minocycline-containing regimens(16%).CONCLUSION The minocycline-containing regimens demonstrated good efficacy,safety,and

关键词： Helicobacter pylori Minocycline Eradication Safety Resistance

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Symmetry dependent activation and reactivity of peroxysulfates on FeS_(2)(001)surface

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Science Bulletin 2024年第2期69卷 154-158页

作者： Cancan ling Meiqi li Hao li Xiufan liu Guangming Zhan Hongwei Sun Chuan liang Yaling li Bing zhou Jincai Zhao lizhi Zhang School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Pesticide&Chemical Biology of Ministry of Education Institute of Environmental&Applied ChemistryCentral China Normal UniversityWuhan 430079China

Heterogeneous peroxysulfates-based advanced oxidation processes(AOPs)have garnered significant attention for purifying organic wastewater since they offer many advantages like low cost,safe storage,facile activation and reactive species participation[1].Nonradical and radical pathways have been proposed to be involved in peroxysulfates activation.

关键词： activation radical reactivity

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