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Synthesis of Cu-Doped Layered Transition Metal Oxide Cathode Materials Directly from Metal-Organic Frameworks for Sodium-Ion Batteries

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Chinese Journal of Chemistry 2023年第20期41卷 2597-2603页

作者： Xiaoniu Hou Changfeng Li Mengjie Li yuansheng liu Wei Zhu Zhenfei Li Yunhua Xu School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education)and Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300072 China

Mn-based layered transition metal oxides are promising cathode materials for sodium-ion batteries(SIBs)because of their high theoretical capacities,abundant raw materials,and environment-friendly advantages.However,they often show insufficient performance due to intrinsic issues including poor structural stability and dissolution of Mn^(3+).Atomic doping is an effective way to address these structural degradation issues.Herein,we reported a new synthesis strategy of a Cu-doped layered cathode by directly calcinating a pure metal-organic framework.Benefiting from the unique structure of MOF with atomic-level Cu doping,a homogeneous Cu-doped layered compound P2-Na_(0.674)Cu_(0.01)Mn_(0.99)O_(2) was obtained.The Cu substitution promotes the crystal structural stability and suppresses the dissolution of Mn,thus preventing the structure degradation of the layered cathode materials.A remarkably enhanced cyclability is realized for the Cu-doped cathode compared with that without Cu doping,with 83.8%capacity retention after 300 cycles at 100 mA·g^(-1).Our findings provide new insights into the design of atomic-level doping layered cathode materials constructed by MOFs for high-performance SIBs.

关键词： Metal-organic frameworks Synthesis design/Sodium-ion batteries Layered cathode materials Atomic doping

Comparing the regeneration potential between PLLA/Aragonite and PLLA/ Vaterite pearl composite scaffolds in rabbit radius segmental bone defects

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Bioactive Materials 2020年第4期5卷 980-989页

作者： Qianli Huang yuansheng liu Zhengxiao Ouyang Qingling Feng State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083PR China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084PR China Public Security College Northwest University of Political Science and LawXi'an710122PR China Department of Orthopedics The Second Xiangya HospitalCentral South UniversityChangsha410083PR China

Mussel-derived nacre and pearl,which are natural composites composed CaCO3 platelets and interplatelet organic matrix,have recently gained interest due to their osteogenic potential.The crystal form of CaCO3 could be either aragonite or vaterite depending on the characteristics of mineralization template within pearls.So far,little attention has been paid on the different osteogenic capacities between aragonite and vaterite pearl.In the current work,aragonite or vaterite pearl powders were incorporated into poly-L-lactic acid(PLLA)scaffold as bio-functional fillers for enhanced osteogenesis.In intro results revealed that PLLA/aragonite scaffold possessed stronger stimulatory effect on SaOS-2 cell proliferation and differentiation,evidenced by the enhanced cell viability,alkaline phosphatase activity,collagen synthesis and gene expressions of osteogenic markers including osteocalcin,osteopotin and bone sialoprotein.The bone regeneration potential of various scaffolds was evaluated in vivo employing a rabbit critical-sized radial bone defect model.The X-ray and micro-CT results showed that significant bone regeneration and bridging were achieved in defects implanted with composite scaffolds,while less bone formation and non-bridging were found for pure PLLA group.Histological evaluation using Masson's trichrome and hematoxylin/eosin(H&E)staining indicated a typical endochondral bone formation process conducted at defect sites treated with composite scaffolds.Through three-point bending test,the limbs implanted with PLLA/aragonite scaffold were found to bear significantly higher bending load compared to other two groups.Together,it is suggested that aragonite pearl has superior osteogenic capacity over vaterite pearl and PLLA/aragonite scaffold can be employed as a potential bone graft for bone regeneration.

关键词： Composite scaffold Aragonite Vaterite Segmental bone defect Bone regeneration

Effects of organic acids on dissolution of Fe and Mn from weathering coal gangue

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Acta Geochimica 2016年第3期35卷 316-328页

作者： Zuyong Chen Fang liu Tongda Bu yuansheng liu Jian Zhu College of Resources and Environmental Engineering Guizhou University College of Agriculture Guizhou University

Understanding the effects of organic acids(OA) on the transformation of Fe and Mn to surface water from the weathering coal gangue is of great bene?t to risk assessment and remediation strategies for contaminated water and soil. Based on the investigation on surface water in the central coal districts of the Guizhou Province, 18 water samples were collected for heavy metal analysis. The results indicated that the p H value of surface water is low(3.11–4.92), and Fe concentration(1.31–5.55 mg L^(-1)) and Mn concentration(1.90–5.71 mg L^(-1)) were, on average,10.86 and 34.33 times the limit of Surface Water Quality Standards, respectively. In order to evaluate the effects of the OA on the dissolution of Fe and Mn from the weathering coal gangue, column elution and batch leaching experiments were conducted. The results show that the low molecular weight of organic acids(LMWOAs, i.e., oxalic,tartaric, malic and citric acids) and fulvic acids signi?-cantly accelerated the dissolution of Fe and Mn; in addition, when the concentration of OA reached 25 mmol L^(-1),the concentrations of Fe, and Mn were 1.14–67.08 and1.11–2.32 times as high as those in 0.5 mmol L^(-1)OA,respectively. Furthermore, the migration of Fe and Mn was signi?cantly in?uenced by the p H and Eh, especially for Fe; the ion Mn was dissolved from the gangue more easily than the ion Fe in the column leaching, which was contrary to the results of batch leaching.

关键词：低分子量有机酸煤矸石 Mn 溶解风化铁浸出实验重金属分析

Hydrogen Bonding-Assisted Synthesis of Silica/Oxidized Mesocarbon Microbeads Encapsulated in Amorphous Carbon as Stable Anode for Optimized/Enhanced Lithium Storage

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Transactions of Tianjin University 2020年第1期26卷 13-21页

作者： Zongjie Cao Huitian liu Wenlong Huang Peng Chen yuansheng liu Yu Yu Zhongqiang Shan Shuxian Meng School of Chemical Engineering and Technology Tianjin University

The practical application of silica-based composites as an alternative to commercial graphite anode materials is hampered by their large volumetric expansion,poor conductivity,and low Coulombic efficiency.In this work,a novel silica/oxidized mesocarbon microbead/amorphous carbon(SiO2/O’MCMB/C)hierarchical structure in which SiO2 is sandwiched between spherical graphite and amorphous carbon shell was succes sfully fabricated through hydrogen bonding-assisted self-assembly and post-carbon coating method.The obtained three-layer hierarchical structure effectively accommodates the volumetric expansion of SiO2 and significantly enhances the electronic conductivity of composite materials.Moreover,the outer layer of amorphous carbon effectively increases the diffusion rate of lithium ions and promotes the formation of stable SEI film.As a result,the SiO2/O’MCMB/C composite exhibits superior electrochemical performance with a reversible capacity of 459.5 mA h/g in the first cycle,and the corresponding Coulombic efficiency is 62.8%.After 300 cycles,the capacity climbs to around 600 mA h/g.This synthetic route provides an efficient method for preparing SiO2 supported on graphite with excellent electrochemical performance,which is likely to promote its commercial applications.

关键词： Hydrogen bonding Silica Oxidized mesocarbon microbead Anode material

地磁的LoRa与NB-IoT通信技术比较研究

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信息与电脑 2024年第7期36卷 239-241页

作者：刘远生深圳市道路交通管理事务中心广东深圳518000

随着物联网技术的快速发展,低功率广域网络(Low-Power Wide-Area Network,LPWAN)以其特有的优势得到广泛的应用。在众多的LPWAN技术应用场景中,地磁作为无线传感器被应用于各种停车管理的场景中,其中,国内停车行业关注度最高的是远距离... 详细信息

随着物联网技术的快速发展,低功率广域网络(Low-Power Wide-Area Network,LPWAN)以其特有的优势得到广泛的应用。在众多的LPWAN技术应用场景中,地磁作为无线传感器被应用于各种停车管理的场景中,其中,国内停车行业关注度最高的是远距离无线电(Long Range Radio,Lo Ra)和窄带物联网(Narrow Band Internet of Things,NB-Io T)两种通信技术的地磁。本文旨在从地磁的Lo Ra与NB-Io T通信技术方面进行系统的梳理和比较分析,为地磁的选择应用提供有力的技术参考和储备。

关键词：地磁 Lo Ra NB-Io T 通信技术

中国增值税区域间横向分配的经济效应:基于多区域CGE模型的分析

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经济研究 2024年第1期59卷 111-128页

作者：刘元生张苏皖李建军西南财经大学财政税务学院 611130

基于生产地原则的增值税地区间分配方式造成地区间税收分配不公,加剧地区间税收竞争、过度投资和重复建设,不利于经济发展方式转变和新发展格局构建。本文建立了一个中国多区域可计算一般均衡模型(CGE),刻画了增值税在地方政府间的横向... 详细信息

基于生产地原则的增值税地区间分配方式造成地区间税收分配不公,加剧地区间税收竞争、过度投资和重复建设,不利于经济发展方式转变和新发展格局构建。本文建立了一个中国多区域可计算一般均衡模型(CGE),刻画了增值税在地方政府间的横向分配机制,对由生产地原则向消费地原则的分配机制改革进行了政策模拟。研究发现:增值税横向分配由生产地原则向消费地原则的改革会显著改善各地区人均增值税收入的不平衡,缩小各地区的财力差异;在完全消费地原则下,相对基准情景,总消费最高增长2.25%,GDP最高增长0.98%;上海等8个地区在四种增值税横向分配机制改革方案下GDP变化率为负,但湖南等大部分地区能从改革中受益,因此改革能促进总体经济增长。本文的研究为构建兼顾生产地和消费地贡献以及利益的地区间增值税横向分配制度提供了理论依据和政策参考。

关键词：增值税横向税收分配生产地原则消费地原则多区域可计算一般均衡模型

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基于实时局部建图的激光雷达长周期定位方法

激光与光电子学进展 2024年第4期61卷 349-356页

作者：齐含刘元盛张军满恂钰张志铭北京联合大学智慧城市学院北京100101 北京市信息服务工程重点实验室北京100101

非结构化道路中的无人驾驶精确定位大量使用基于激光雷达的simultaneous localization and mapping(SLAM)技术,解决因环境变化导致的预建地图匹配失败,进而引起定位丢失的问题一直是业内难题和热点研究方向之一。针对上述问题,提出一种... 详细信息

非结构化道路中的无人驾驶精确定位大量使用基于激光雷达的simultaneous localization and mapping(SLAM)技术,解决因环境变化导致的预建地图匹配失败,进而引起定位丢失的问题一直是业内难题和热点研究方向之一。针对上述问题,提出一种利用激光雷达和惯性测量单元在normal distribution transform(NDT)定位基础上融合实时局部地图匹配的长周期鲁棒定位方法online location normal distributions transform(OL-NDT)。OL-NDT将NDT获得的定位信息作为测量信息因子输入因子图中优化实时构建的局部地图,并且在其全局定位丢失后采用实时局部地图进行定位。在MulRan数据集上进行定位精度测试,OL-NDT的累计误差占比为0.40%,较现有的传统定位方法降低了1.06个百分点,定位精度得到了有效提升,且在静态结构发生较大变化的场景下也可以精准定位。同时,利用在北京联合大学采集的校园数据验证了在短暂无地图情况下OL-NDT的定位轨迹精度与已知地图时完全匹配。

关键词：激光雷达无人驾驶长周期可靠定位正态分布变换因子图

Future vehicles: interactive wheeled robots

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Science China(Information Sciences) 2021年第5期64卷 212-214页

作者： Nan MA Deyi LI Wen HE Yue DENG Jiahong LI Yue GAO Hong BAO Huan ZHANG Xinkai XU yuansheng liu Zhixuan WU Li CHEN Beijing Key Laboratory of Information Service Engineering Beijing Union University College of Robotics Beijing Union University Institute of System Engineering Academy of Military Science School of Astronautics Beihang University School of Software Tsinghua University Smart City College Beijing Union University Demonstration Center of Experimental Teaching in Comprehensive Engineering Beijing Union University

Owing to the lack of variety of interactions in automatic driving, the interactive cognition and evolution growth of self-driving vehicles in uncertain and complex environments have been proposed, making future vehicl... 详细信息

关键词： interactive cognition evolution growth wheeled robots prior knowledge driving skills

Electroacupuncture at Ren channel point combined with injection of basic fibroblast growth factors for neural stem cell proliferation in subventricular zone of cerebral ischemic side

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Neural Regeneration Research 2006年第5期1卷 424-427页

作者： Min Pi Lihong Diao Haibo Yu Xiaodan Rao Ling Wang yuansheng liu Wenshu Luo Zhuoxin Yang Department of Acupuncture and Moxibustion Shenzhen Hospital Guangzhou University of Traditional Chinese Medicine Shenzhen 518033 Guangdong Province China Postdoctoral Station of Guangzhou University of Traditional Chinese Medicine Guangzhou 510405 Guangdong Province China

BACKGROUND： Electroacupuncture at Ren channel point can treat stroke and generate some neurodevelopment-related growth factors, which are associated with the proliferation and differentiation of stem cells. OBJECTIVE： To observe the effect of electroacupuncture at Ren channel point combined with injection of basic fibroblast growth factors （bFGF） on the expression of 5-bromo-2-deoxyuridine （BrdU）-Iabeled and BrdU/Neuroepthelial stem cell protein （Nestin）-Iabeled positive cells in subventricular zone of cerebral ischemic rats. DESIGN ： Completely randomized grouping design and controlled trial.SETTING： Department of Acupuncture and Moxibustion, Shenzhen Hospital, Guangzhou University of Traditional Chinese Medicine. MATERIALS ： Eighty-four adult healthy male Wistar rats were involved and divided into 5 groups by a lot： blank group （n =6）, sham-operation group （n =6）, model group （n =26）, injection of bFGF group （bFGF group, n =24） and electroacupuncture at Ren channel combined with injection of bFGF group （bFGF group, n =22）. Three time points were set in each of the latter three groups for observation： 7, 14 and 28 days after ischemia respectively. Mouse BrdU and Nestin monoclonal antibody （analytical pure, China）, G6805 electro-acupuncture apparatus （Huayi Medical Instrument, Shanghai） and Olympus FV 500 laser confocal microscope （Olympus Company） were used. METHODS ： This trial was carried out in the Laboratory of Anatomy, Medical College of Sun Yat-sen University from September 2004 to July 2005. ① Except for blank group and sham-operation group, the rats in the other groups were prepared into rat models of local cerebral ischemia by suture-occluded method. The rats were reperfused, and then they were graded in neurologic deficits based on neurological scoring of Longa. Rat model was successful when the neurological scoring ranged from 1 to 4 points and used for the trial. Blank group was untouched; Right common carotid artery was isolated and right external carotid artery was dissected without embolis

关键词： subventricular zone cell proliferation cerebral ischemia normal group Traditional Chinese Medicine growth factors common carotid artery Acupuncture and Moxibustion neural stem cells monoclonal antibody confocal microscope synergistic effect Guanyuan point Wistar rats time point