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Chinese Journal of Polymer Science 2006年第1期24卷 21-27页

作者： Xi-jie Liu jun-quan sun Hai-ying Zhang Xiao-hui Xiao and Feng Lin Department of Chemical Engineering,College of Material and Chemical Engineering,Zhejiang University,Hangzhou 310027,China Department of Chemical Engineering College of Material and Chemical Engineering Zhejiang University Hangzhou 310027 China

By treating disodium（thiophenedimethylene）dicyclopentadienide C4H2S（CH2C5H4Na）2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2] （M = Ti 3, M = Zr 4） were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3, 4） reached 2.44 × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3, 4） and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

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A modified LC-MS/MS method for determination of tetramethylpyrazine in microdialysis samples and calibration of home-made linear probes

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A modified LC-MS/MS method for determination of tetramethylp...

First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

加快转变医药发展方式，占领科学技术制高点——2011年中国药学大会暨第11届中国药师周

作者： Jin-Zhao HAN,jun sun,quan-Gang Zhu,Ji-Yong Liu,Jin-Hong Hu

川芎嗪是传统中药川芎中重要的有效成分,广泛应用于心血管疾病的治疗。川芎嗪经皮给药后,有许多因素影响川芎嗪进入生物体并对药物的分布、代谢造成差异。本研究建立并优化一种新的、高效的LC-MS/MS方法用于测定皮肤微透析样品中的川芎... 详细信息

川芎嗪是传统中药川芎中重要的有效成分,广泛应用于心血管疾病的治疗。川芎嗪经皮给药后,有许多因素影响川芎嗪进入生物体并对药物的分布、代谢造成差异。本研究建立并优化一种新的、高效的LC-MS/MS方法用于测定皮肤微透析样品中的川芎嗪含量。液相色谱柱选用安捷伦ZorboxC18柱(3.5μm,100mm×2.1mmi.d.),流动相选用甲醇:水:醋酸(50:50:0.6),流速为0.3mL/min。川芎嗪和内标咖啡因的保留时间分别为1.89、1.17分钟。通过分析组织切片确定了探针植入后纤维囊的形成,研究表明纤维囊的形成没有影响自制线性探针对川芎嗪的回收率,自制线性探针在皮肤微透析实验过程中有很好的稳定性。本研究建立并优化川芎嗪的LC-MS-MS分析方法,对自制线性探针稳定性进行了考察,实验结果表明所建立的分析方法高效、准确,能满足皮肤微透析实验的要求。

关键词：微透析 LC-MS/MS 回收率线性探针纤维囊

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin sun Qiugang ZONG Gaopeng LU Xudong GU Ze-jun HU Bin LI Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space Sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1

Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu Yue Li jun sun Shuyuan Du Xinpeng Di Yuguang Yang Bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

氧化石墨阳离子交换容量测定过程中结构的变化

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物理化学学报 2017年第2期33卷 413-418页

作者：王泉珺孙红娟彭同江冯明珠西南科技大学理学院四川绵阳621010 西南科技大学矿物材料及应用研究所四川绵阳621010 西南科技大学分析测试中心四川绵阳621010

氧化石墨(GO)结构层上的碳羟基(―C―OH)和边缘羧基(―COOH)在水介质中发生质子化反应解离出的H+具有阳离子可交换性。实验采用甲醛缩合法测量了GO的阳离子交换容量(CEC),用X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱和X射线光电子能谱(... 详细信息

氧化石墨(GO)结构层上的碳羟基(―C―OH)和边缘羧基(―COOH)在水介质中发生质子化反应解离出的H+具有阳离子可交换性。实验采用甲醛缩合法测量了GO的阳离子交换容量(CEC),用X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱和X射线光电子能谱(XPS)分析测试手段对GO阳离子交换过程中间产物的结构变化进行了分析。结果表明,GO的CEC高达541.48 mmol/100 g。NH_4^+和Ca^(2+)交换后的GO,保持稳定的层状结构,c轴方向层间距分别增大了0.1499和0.2905 nm。NH_4+和Ca^(2+)主要以层间可交换阳离子形式存在于层间域中,并与水分子形成可交换水化阳离子层,部分以[NH_4(H_2O)_6]+和[Ca(H_2O)_6]_2+的形式存在于结构层的边缘附近,共同平衡结构层水解产生的负电荷。

关键词：氧化石墨含氧官能团阳离子交换容量层间域结构变化

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Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen Yu Han jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

航空升压式空气循环制冷组件动态特性的仿真研究

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系统仿真学报 2004年第4期16卷 727-729页

作者：何君赵竞全孙薇北京航空航天大学505教研室北京100083

详细描述了航空升压式空气循环制冷组件的工作原理。建立了该组件中压气机、涡轮、转轴以及中间冷却器的非线性动态模型。根据部件动态特性的不同时间尺度,分别考虑气体的压力、温度以及转轴转速随时间的变化过程。在MATLAB/SIMULINK系... 详细信息

详细描述了航空升压式空气循环制冷组件的工作原理。建立了该组件中压气机、涡轮、转轴以及中间冷却器的非线性动态模型。根据部件动态特性的不同时间尺度,分别考虑气体的压力、温度以及转轴转速随时间的变化过程。在MATLAB/SIMULINK系统仿真环境下,采用模块化的建模思想开发了该组件的动态仿真工具箱。以某型飞机环境控制系统的升压式空气循环制冷空气循环制冷组件为例,进行了仿真计算并给出系统的稳态结果和动态过程分析。

关键词：空气循环制冷数学模型动态仿真飞机环境控制系统

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Construction of Power Trading Supply Guarantee System of High Proportion of Hydropower in the Southwest Power Grid Under Extreme Climate Scenarios

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Dianwang Jishu/Power System Technology 2025年第1期49卷 113-123页

作者： Wen, Xu Zhou, quan sun, Tian Yang, Yang Mao, Rui Wen, Siao Southwest Branch of State Grid Corporation of China Sichuan Province Chengdu 610041 China Beijing Power Trading Center Co. Ltd. Xicheng District Beijing 100031 China

Currently, the Southwest Power Grid is promoting the construction of a new power system. The southwest power grid has a large-scale integration of clean energy, mainly hydropower, which depends on the weather. The system operation is facing serious challenges due to the lack of reliable power supply and the frequent occurrence of extreme climate. Firstly, this paper introduces China's Southwest Power Grid and market operation pattern. Secondly, learning from the power supply issues in the Sichuan-Chongqing region of the Southwest Power Grid under the extreme drought, and high-temperature climate scenarios in the summer of 2022, and based on the perspectives of the regional power grid and the marketization, the paper summarizes the four shortcomings of current power supply scheme of Southwest Power Grid, namely limited warning levels, short supply cycle, limited supply space, and a single supply resource. Therefore, research methods and framework for the power supply of Southwest Power Grid are proposed based on the concept of "double-level, full-lifecycle, full-space, and full-resources" ("one-double three-full"). Thirdly, the power trading system for supply sufficiency in Southwest Power Grid under extreme climate scenarios is constructed: 1) proposing the concept and level determination method of power supply warning and response for regional power grids, and constructing a double-level power trading supply warning and response mechanism for "provincial power grid + regional power grid";2) proposing medium and long term interruptible power supply varieties and constructing a "medium and long term + spot + emergency" full-lifecycle power trading supply guarantee system;3) proposing the concept of inter-regional and intra-provincial market power supply, designing spatiotemporal exchange transactions of large-scale hydropower and constructing a "inter-regional + inter-provincial + intra-provincial" full-space power trading system for supply sufficiency;4) proposing p

关键词： Commerce

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

Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin

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Journal of Geographical Sciences 2025年第1期35卷 88-111页

作者： YANG Peng sun Kaiya ZHU Yanchao XIA jun HUANG Heqing SONG Jingxia SHI Xiaorui LU Xixi Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information Engineering China University of Geosciences Department of Geography National University of Singapore State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Wetlands play a critical role in the global environment. The Middle Yangtze River Basin(MYRB), known for its abundant wetland resources, has experienced notable changes resulting from the complex interplay of environmental factors. Therefore, we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to *** the random forest(RF) regression algorithm and patch-generated land-use simulation(PLUS) model, we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP) framework from 2035 to 2095. The main findings are as follows:(1) The RF algorithm was optimal for land-use and land-cover(LULC) classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings. However, the forested area exhibited an increase and decrease of 3.9% and 1.2% under the SSP1-2.6 and SSP5-8.5 scenarios, respectively, whereas farmland exhibited a diminishing trend.(2) Wetlands were primarily concentrated in the central and eastern MYRB, with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020. Notably,wetland coverage revealed significantly high level, significant changes, frequent but relatively minor changes under the SSP1-2.6, SSP2-4.5, and SSP 5-8.5 scenarios, respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities, indicating a clear degradation in habitat quality across different scenarios. In conclusion, we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds.

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