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Effect of nano-SiC particles on the corrosion resistance of NiP-SiC composite coatings

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 444-451页

作者： Xue-tao Yuan dong-bai sun Hong-ying Yu Yu Wang School of Materials Science and Technology University of Science and Technology Beijing Beijing 100083 China Beijing Engineering-Research Center for Surface Nano-Technology Beijing 100083 China

NiP-SiC （≈1 1wt% P） composite coatings were electroplated in a Brenner type plating bath. The coatings had amorphous nano-phase composite structure. Direct current and alternating current electrochemical tests were carried out on such coatings in a 3.5wt% solution of NaCl to evaluate their corrosion resistance. The potentiodynamic polarization, electrochemical impedance spectroscopy （EIS） tests, and exposure experiments all show that the corrosion resistance of NiP-SiC coatings first increases and then decreases when the SiC content increases, but the corrosion resistance of NiP-SiC composite coating is better than that of amorphous NiP coatings.

关键词： electroplating composite coating nanoparticle corrosion resistance electrochemical impedance spectroscopy

Devitrification of Al-Ce Amorphous Ribbon Investigated Using In situ High Energy X-ray Diffraction

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Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 157-162页

作者： Ying-Xi Li Fan-Qiang Meng Rui Yuan Guo-Qiang Huang dong-bai sun Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai519082China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou510275China

Metastable phases formed during vitrification or devitrification open an avenue to study the intrinsic structural hierarchy in amorphous *** phase transformation sequence of Al89Ce11 amorphous ribbon was investigated using diff erential scanning calorimetry,in situ high energy X-ray diffraction(HEXRD)and ex situ high-resolution scanning transmission electron *** results reveal the devitrification pathway following the reaction:amorphous→ε-Al_(60)Ce_(11)+fcc-Al→η-Al_(41)Ce_(5)+fcc-Al→Al_(11)Ce_(3)+*** has been found that bothε-Al_(60)Ce_(11)andη-Al_(41)Ce_(5)metastable phases have same Ce-centered 1-6-6-6-1 motif,suggesting that the structural motif can be *** of metastable phase with large unit cell is related to the short-range orders developed during *** heredity provides a new method to tailor the microstructure and properties of Al-based alloys based on genetic mechanism.

关键词： Synchrotron radiation Amorphous alloys Crystallization Phase transformation

Characterization and wear behavior of WC-0.8Co coating on cast steel rolls by electro-spark deposition

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 707-713页

作者： Jian-sheng Wang Hui-min Meng Hong-ying Yu Zi-shuan Fan dong-bai sun School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To prepare high wear resistance and high hardness coatings, electro-spark deposition was adopted for depositing an electrode of a mixture of 92wt%WC＋8wt%Co on a cast steel roll substrate. The coating was characterized by classical X-ray diffractometer （XRD） and scanning electron microscopy （SEM） with energy dispersive X-ray analysis （EDX）. The results indicate that the coating shows nanosized particulate structure and dendritic structure including columnar structure and equiaxed structure. The primary phases of the coating contain Fe3W3C, Co3W3C, Fe2C and Si2W. The coating has a low friction coefficient of 0.13, its average wear-resistance is 3.3 times that of the cast steel roll substrate and the main mechanism is abrasive wear. The maximum microhardness value of the coating is about 1573.9 Hv0.3. The study reveals that the electro-spark deposition process has the characteristic of better coating quality and the coating has higher wear resistance and hardness.

关键词： electro-spark deposition (ESD) WC-Co coatings microstructure wear resistance

基于粒子群优化算法的结构可靠度敏感性分析方法:相对收敛率（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第12期17卷 961-973页

作者： Cheng-ming LAN Hui LI Jun-yi PENG dong-bai sun National Center for Materials Service Safety University of Science & Technology Beijing Research Center of Structural Monitoring and Control School of Civil Engineering Harbin Institute of Technology CITIC Construction Co. Ltd.

目的:采用粒子群优化算法(PSO)提高可靠指标计算效率,探讨PSO求解过程中粒子群在不同维上统计特性及其收敛速率表征的物理含义,研究优化过程中粒子收敛速率与随机变量敏感性的关系,提出可靠度敏感性分析新方法。创新点:1.根据PSO寻优过... 详细信息

目的:采用粒子群优化算法(PSO)提高可靠指标计算效率,探讨PSO求解过程中粒子群在不同维上统计特性及其收敛速率表征的物理含义,研究优化过程中粒子收敛速率与随机变量敏感性的关系,提出可靠度敏感性分析新方法。创新点:1.根据PSO寻优过程中粒子在不同维上收敛速率不同,提出采用收敛速率表征随机变量的敏感性;2.建立最优化策略组避免粒子群收敛过程中产生波动,保证最优化策略组内粒子在不同维上连续收敛,定义相对收敛率表征随机变量敏感性。方法:1.根据Hasofer-Lind可靠指标的几何意义,建立可靠指标的优化模型,提出采用改进的PSO求解可靠指标与验算点,采用可行策略方法处理约束条件;2.通过理论推导,构造PSO迭代过程的最优评价函数集(公式(18)),建立最优化策略组保证粒子在不同维上连续收敛,提出表征随机变量敏感性的相对收敛率计算公式(公式(19));3.通过数值模拟并与传统基于梯度的敏感性分析计算结果比较,验证本文所提方法的可行性和有效性。结论:1.相对收敛率可以表征随机变量的敏感性;2.最优化策略组避免相对收敛率的波动,保证候选粒子变异系数曲线在解空间内连续收敛;3.最优化策略组内随机变量候选解的变异系数越小则其表征的随机变量越敏感;4.基于PSO的可靠度及敏感性分析对复杂问题更有效。

关键词：敏感性分析优化结构可靠度随机变量

Geochemical characteristics and genetic type of a lithium ore (mineralized) body in the central Yunnan Province, China

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China Geology 2019年第3期2卷 287-300页

作者： bai-dong sun Jun-ping Liu Xiao-hu Wang Yan Dao Gui-xiang Xu Xiao-zhuang Xue-qing Guan Wei Wang dong-hu Song Yunnan Institute of Geological Survey Kunming 650216China Kunming University of Science and Technology Kunming 650093China Chengdu Center China Geological SurveyMinistry of Natural ResourcesChengdu 610081China

Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan Formation. This work described the morphology, structures, main ore types and geochemical characteristics of this ore body in detail, and discussed the ore-forming material source, occurrence state of lithium and the formation mechanism of lithium ores to clarify the prospecting marks. In the further exploration, comprehensive evaluation of the lithium resources of known bauxite ore bodies in central Yunnan Province should be strengthened, and the exploration of hidden lithium ore bodies should be intensified in order to discover more large and super-large lithium orebodies, which will fill the gap of the national demand for lithium resources, and promote the national defense construction and new energy industry development.

关键词： Sedimentary-type lithium deposit Stratified deposit Geochemical characteristics Metallogenic mechanism Mineral resources exploration engineering Yunnan Province China

Protoconodont fossils for refining the Cambrian bottom and the contribution to shale gas formation along the southwest margin of Yangtze Block

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China Geology 2020年第4期3卷 558-566页

作者： Jun-ping Liu Si-cun Song Wei Wang Feng Tang Jing Li Xiang-dong Duan Xiao-hu Wang bai-dong sun Sai-ying Yu Shao-bin Hu Wen-ting Duan Yunnan Institute of Geological Survey Kunming 650216China Key Laboratory of Sanjiang Metallogeny and Resources Exploration and Utilization Ministry of Natural ResourcesKunming 650051China Department of Earth Sciences University College LondonLondon WC1E6BTUnited Kingdom Key Laboratory of Stratigraphy and Palaeontology Chinese Academy of Geological SciencesMinistry of Natural ResourcesBeijing 100037China Yunnan Institute of Land and Resources Planning and Design Kunming 650216China Yunnan Department of Natural Resources Kunming 65000China

It has been an intense debate on the exact boundary between Ediacaran and Cambrian in the southwest Yangtze *** calibration of this critical boundary has a remarkable influence on the further investigation of the break-up of the Rodinia Supercontinent,the early life evolution,and the mechanism of the phosphorite *** and Cambrian strata and fossils are widely distributed in Anning,Yunnan Province in *** recent years,the Xiaowaitoushan Member from the Lower Yuhucun Formation has been *** this interval with continuous collections,the first appearance datums(FADs)of the protoconodont(Fomitchella *** Yang et He,Protohertzina *** Missarzhevsky)and globular embryos fossil(Olivooides sp.)earlier than these in the Lower Cambrian strata of the Meishucun Formation were *** discovery indicates that the Xiaowaitoushan Member has included more FADs than the previously discovered single FAD of Anabarites primitivus Qian et Jiang,and the Ediacaran–Cambrian boundary in southwest China should be replaced below the Point“A”of the Meishucun Formation in Yunnan *** Point“B”of the Meishucun Formation is younger than the suggested age 541 Ma of the Ediacaran–Cambrian boundary and can no longer reference the Global Boundary Stratotype Section and Point(GSSP)correlation in southwest *** can be suggested based on the previous stratigraphy and palaeontology studies from northern Sichuan and southern Shaanxi and the FAD of the globular embryos fossils that the Ediacaran‒Cambrian boundary in the southwest Yangtze Block should be placed at the base of the Xiaowaitoushan Member;other phosphorite strata refer to Xiaowaitoushan *** discovery of the FADs of the shelly fossils in the Xiaowaitoushan Member provides new evidence for the global correlation of the Ediacaran–Cambrian boundary in the southwest Yangtze *** conodont discoloration index(CAI)of the specimens in Anning is between 2 and 3,which indicates

关键词： Shale gas Ediacaran-Cambrian boundary Protoconodont Embryos fossil Xiaowaitoushan Member Southwest Yangtze Block Geological survey engineering Yunnan Province China

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin Peng Yu bai Hang Li Meixiu Qu Zhenhua Wang Kening sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

2D CaWO4 nanosheets derived from scheelite minerals for enhanced electrocatalysis in oxygen evolution reaction

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Science China Chemistry 2025年

作者： Qing sun Yongxiang sun Yan dong Hong Zhong Hongbo Zeng National&Local United Engineering Laboratory for New Petrochemical Materials&Fine Utilization of Resources College of Chemistry and Chemical EngineeringHunan Normal University Department of Chemical and Materials Engineering University of Alberta College of Chemistry and Materials Engineering Hunan University of Arts and Science College of Chemistry and Chemical Engineering Central South University

Scheelite （CaWO4） mineral holds promise as a cost-effective and efficient catalyst for the oxygen evolution reaction （OER）crucial in renewable energy ***,challenges such as limited active site exposure and low electrocatalytic performance need *** this work,we have fabricated two-dimensional （2D） CaWO4nanosheets from scheelite minerals via a straightforward ultrasonic exfoliation method and evaluated their efficacy as OER *** to scheelite powders,these 2D nanosheets exhibited superior crystallinity and a 1.26-fold increase in electrochemical surface area,promoting active site *** 2D CaWO4nanosheet electrode demonstrated outstanding OER catalytic performance,achieving a current density of 20 mA/cm2at an overpotential of 290 m V in alkaline conditions,which was lower than that of bulk CaWO4electrodes （～340 mV）.Density functional theory calculations attributed this enhanced catalytic performance to moderate adsorption of oxygenated intermediates （*OH,*O,and*OOH） on the W sites of 2D *** situ electrochemical atomic force microscopy tests also confirmed the catalytic enhancement by 2D CaWO4nanosheets during *** findings demonstrate the potential of affordable and abundant mineral resources in advancing electrochemical catalysts for oxygen evolution,highlighting their broader application in sustainable energy technologies.

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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