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Room-temperature ferrimagnetism and size-modulated electronic structures in two-dimensional cluster-based metal-organic frameworks

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Science China Chemistry 2024年第4期67卷 1334-1340页

作者： jing cheng Xingxing Li Jinlong Yang Key Laboratory of Precision and Intelligent Chemistry University of Science and Technology of ChinaHefei 230026China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Cluster-assembled materials have attracted particular attention for their complex hierarchical structures and unique ***,the majority of cluster-based assemblies developed so far are either non-magnetic or only exhibit magnetic ordering with a relatively low Curie temperature,limiting their applications in ***,two-dimensional(2D)cluster-assembled materials with room-temperature magnetism remain highly *** this purpose,based on first principles calculations,we design a series of thermodynamically stable 2D cluster-based metal-organic frameworks(MOFs)Fe_(n)-(pyz)(n=1-6)by utilizing Fenmetal clusters as nodes and nitrogen-containing pyrazine ligands as organic *** 2D cluster-based MOFs exhibit robust ferrimagnetic ordering due to the strong d-p direct exchange interaction between d-electron spin of Fe_(n)(n=1-6)clusters and charge transfer-induced p-electron spin of pyrazine *** particular,the ferrimagnetic Curie temperatures are well above room temperature(up to 836 K).Additionally,altering the size of Fe_(n)clusters in Fe_(n)-(pyz)(n=1-6)MOFs results in diverse functional spintronic properties,including bipolar magnetic semiconductors,half semiconductors and Dirac half ***,these 2D assembled MOFs possess sizable magnetic anisotropy energies,up to 9.16 me V per formula.

关键词： metal-organic framework two-dimensional material half metal bipolar magnetic semiconductor magnet

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Tin recovery from a low-grade tin middling with high Si content and low Fe content by reduction–sulfurization roasting with anthracite coal

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 210-220页

作者： jing-cheng Wang Lei Li Yong Yu State Key Laboratory of Complex Non-ferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction of Ministry of Education Kunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

A new method for separating and recovering tin from a low-grade tin middling with high Si content and low Fe content by roasting with anthracite coal was researched by studying the reaction mechanism and performing an industrial test,in which the Sn was sulfurized into SnS(g)and then collected using a dust *** Fe–Sn alloy may be formed at roasting temperatures above 950°C,and like the roasting temperature increases,the Sn content and Sn activity in this Fe–Sn alloy ***,more FeS can be formed at higher temperatures and then the formation of FeO–FeS with a low melting point is promoted,which results in more serious sintering of this low-grade tin *** from the thermodynamics and kinetics points of view,the volatilization of the Sn decreases at extremely high roasting *** results of the industrial test carried out in a coal-fired rotary kiln show that the Sn volatilization rate reaches 89.7%and the Sn is concentrated in the collected dust at a high level,indicating that the Sn can be effectively extracted and recovered from the low-grade tin middling with a high Si content and low Fe content through a reduction–sulfurization roasting process.

关键词： low-grade tin middling tin recovery roasting process Fe-Sn alloy resource recycling

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乡村振兴视角下朱德“三农”思想探析

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齐齐哈尔大学学报(哲学社会科学版) 2025年第1期 54-57页

作者：成靖邵彦涛华中师范大学马克思主义学院湖北武汉430079

新中国成立后,朱德充分认识到农业在社会主义建设中的基础地位,在深入各地调查研究的过程中形成了一套关于“三农”工作较为全面和系统的思想。他主张加强水利、交通等基础设施建设,要求国家从财政、税收、科技等方面支持农业农村的发展... 详细信息

新中国成立后,朱德充分认识到农业在社会主义建设中的基础地位,在深入各地调查研究的过程中形成了一套关于“三农”工作较为全面和系统的思想。他主张加强水利、交通等基础设施建设,要求国家从财政、税收、科技等方面支持农业农村的发展,鼓励各地根据资源禀赋制定农业发展规划,强调基层党组织的建设等,内容涉及农业基础设施建设、产业规划、基层党组织建设、政策保障等多个方面。朱德针对“三农”工作提出的诸多建议,不仅在当时发挥了重要的作用,更成为社会主义建设时期我党积累的宝贵经验、回顾朱德“三农”思想,对实施我国乡村振兴战略具有重要的借鉴意义。

关键词：朱德三农思想乡村振兴战略

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乡村振兴背景下高素质农民培育的现存问题及解决对策

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泰州职业技术学院学报 2025年第1期25卷 41-44页

作者：程静卜潇殷玲江苏农牧科技职业学院江苏泰州225300

高素质农民培育是加速推进乡村振兴战略的重要环节,对我国全面实现农业农村现代化大有裨益。文章在我国实施乡村振兴战略大背景下,就当下高素质农民培育工作中存在的问题提出针对性的对策,以期为乡村振兴战略的实施和现代农业的发展提... 详细信息

高素质农民培育是加速推进乡村振兴战略的重要环节,对我国全面实现农业农村现代化大有裨益。文章在我国实施乡村振兴战略大背景下,就当下高素质农民培育工作中存在的问题提出针对性的对策,以期为乡村振兴战略的实施和现代农业的发展提供理论依据。

关键词：高素质农民培育乡村振兴

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Analyzing the Urban Hierarchical Structure Based on Multiple Indicators of Economy and Industry: An Econometric Study in China

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1831-1855页

作者： jing cheng Yang Xie Jie Zhang School of Architecture Tsinghua UniversityBeijing100084China Beijing Tsinghua Tongheng Urban Planning&Design Institute Beijing100085China

For a city,analyzing its advantages,disadvantages and the level of economic development in a country is important,especially for the cities in China developing at flying *** corresponding literatures for the cities in China have not considered the indicators of economy and industry in *** this paper,based on multiple indicators of economy and industry,the urban hierarchical structure of 285 cities above the prefecture level in China is *** indicators from the economy,industry,infrastructure,medical care,population,education,culture,and employment levels are selected to establish a new indicator system for analyzing urban hierarchical *** factor analysis method is used to investigate the relationship between the variables of selected indicators and obtain the score of each common factor and comprehensive scores and rankings for 285 cities above the prefecture level in *** to the comprehensive scores,285 cities above the prefecture level are clustered into 15 levels by using K-means clustering ***,the hierarchical structure system of the cities above the prefecture level in China is obtained and corresponding policy implications are *** results and implications can not only be applied to the urban planning and development in China but also offer a reference on other developing *** methodologies used in this paper can also be applied to study the urban hierarchical structure in other countries.

关键词： Urban planning hierarchical structure prefecture-level city factor analysis method K-means clustering algorithm China

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New Dopa-AIE Compound Used as Fluorescence Sensor Material： Specificity and Quantification for Cu（Ⅱ）

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Chinese Journal of Chemistry 2017年第3期35卷 335-340页

作者： Siwei Liu jing cheng Jiarui Xu PCFMLab and GDHPPC Lab School of Chemistry Sun Yat-sen University Guangzhou Guangdong 510275 China Department of Materials Soience and Engineering and Bioengineering Univer~s'ity of California Berkeley CA 94702 U. S. A.

As a paramagnetic metal ion, Cu(II) is challenging to be detected by conventional fluorescence sensor because of its unselective paramagnetic quenching effects on common fluorophores. By combining catechol with tetraphenylethene, a typical aggregation-induced emission (AIE) moiety, we have successfully synthesized a new kind of catechol, the dopa-AIE compound. Due to the properties of AIE core, the catechol has the “turn on” mechanism as a fluorescence chemosensor. Specifically, the new catechol has the unique detection selectivity on Cu(II) in solution. The fluorescence intensity has the maximum value when the molar ratio of the catechol to Cu(II) is 1∶1. Before and after this point, the fluorescence intensity shows a linear relationship with the copper ion concentration, increasing or decreasing. Thus, the quantitative calculation for Cu(II) or the dopa-AIE compound could be done according to this response process.

关键词： dopamines biosensors copper fluorescence redox

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Measuring spatio-temporal autocorrelation in time series data of collective human mobility

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Geo-Spatial Information Science 2019年第3期22卷 166-173页

作者： Yong Gao jing cheng Haohan Meng Yu Liu Institute of Remote Sensing and Geographic Information System School of Earth and Space SciencesPeking UniversityBeijingChina

Massive spatio-temporal big data about human mobility have become increasingly *** underlying dynamic patterns from these data is essential for understanding people’s behavior and urban ***-temporal autocorrelation analysis is an exploratory approach to recognizing data distribution in space and *** most widely used spatial autocorrelation measurements,such as Moran’s I and local indicators of spatial association(LISA),only apply to static data,so are powerless to spatio-temporal big data about human ***,we proposed a new method by extending Moran’s I to measure the spatial autocorrelation of time series *** the method was applied to taxi ride data in Beijing,China to reveal the spatial pattern of collective human *** result shows that there is strong positive spatio-temporal autocorrelation within the 5th Ring Road,weak negative spatio-temporal autocorrelation nearby the Sixth Ring Road,and almost no spatiotemporal autocorrelation between the *** spatial patterns of taxi travel were also *** method is useful for discovering underlying patterns from spatio-temporal big data to understand human mobility.

关键词： Taxi rides human mobility spatio-temporal autocorrelation Moran index

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Optimizing weighting functions for cryo-electron microscopy

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Biophysics Reports 2021年第2期7卷 152-158页

作者： jing cheng Xinzheng Zhang National Laboratory of Biomacromolecules CAS Center for Excellence in Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Center for Biological Imaging CAS Center for Excellence in Biomacromolecules Institute of Biophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

The frequency-dependent signal to noise ratio of cryo-electron microscopy data varies dramatically with the frequency and with the type of the data. During different steps of data processing, data with distinct SNR are used for calculations. Thus, specific weighting function based on the particular SNR should be designed to optimize the corresponding calculation. Here, we deduced these weighting functions by maximizing the signal to noise ratio of cross correlated coefficients. Some of our weighting functions for refinement resemble that used in the existing software packages. However, weighting functions we deduced for motion correction, particle picking and the refinement with overlapping densities differ from those employed by existing programs. Our new weighting functions may improve the calculation in these steps.

关键词： Cryo-electron microscopy (Cryo-EM) Cross correlation coefficient (CCC) Weighting function

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Transverse Effects in Slow Light Propagation

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量子光学学报 2006年第B8期12卷 71-72页

作者： jing cheng Key Laboratory for Quantum Optics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 China

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Small molecules for mesenchymal stem cell fate determination

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World Journal of Stem Cells 2019年第12期11卷 1084-1103页

作者： Yu-Hao cheng jing-cheng Dong Qin Bian Institute for Cell Engineering Johns Hopkins University School of MedicineBaltimoreMD 21205United States Department of Integrative Medicine Huashan HospitalFudan UniversityShanghai 200040China

Mesenchymal stem cells(MSCs)are adult stem cells harboring self-renewal and multilineage differentiation potential that are capable of differentiating into osteoblasts,adipocytes,or chondrocytes in vitro,and regulating the bone marrow microenvironment and adipose tissue remodeling in *** process of fate determination is initiated by signaling molecules that drive MSCs into a specific *** of MSC fate determination leads to different bone and adipose tissue-related diseases,including aging,osteoporosis,and insulin *** progress has been made in recent years in discovering small molecules and their underlying mechanisms control the cell fate of MSCs both in vitro and in *** this review,we summarize recent findings in applying small molecules to the trilineage commitment of MSCs,for instance,genistein,medicarpin,and icariin for the osteogenic cell fate commitment;isorhamnetin,risedronate,and arctigenin for pro-adipogenesis;and atractylenolides and dihydroartemisinin for chondrogenic fate *** highlight the underlying mechanisms,including direct regulation,epigenetic modification,and post-translational modification of signaling molecules in the AMPK,MAPK,Notch,PI3K/AKT,Hedgehog signaling pathways *** discuss the small molecules that are currently being studied in clinical *** target-based manipulation of lineage-specific commitment by small molecules offers substantial insights into bone marrow microenvironment regulation,adipose tissue homeostasis,and therapeutic strategies for MSC-related diseases.

关键词： Mesenchymal stem cell Mesenchymal stromal cell Cell fate determination Small molecules Natural compounds Signaling pathways

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