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Oxide cathodes for sodium-ion batteries:Designs,challenges,and perspectives

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Carbon Energy 2022年第2期4卷 170-199页

作者： Tao Chen Baixue Ouyang Xiaowen Fan Weili Zhou weifang liu Kaiyu liu College of Chemistry and Chemical Engineering Central South UniversityChangshaP.R.China Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangshaP.R.China College of Chemistry and Chemical Engineering Hunan UniversityChangshaP.R.China

Sodium-ion batteries(SIBs),which are an alternative to lithium-ion batteries(LIBs),have attracted increasing attention due to their low cost of Na resources and similar Na storage mechanism to LIBs.Compared with anode materials and electrolytes,the development of cathode materials lags behind.Therefore,the key to improving the specific energy and promoting the application of SIBs is to develop high-performance sodium intercalation cathode materials.Transition-metal oxides are one of the most promising cathode materials for SIBs owing to their excellent energy density,high specific discharge capacity,and environmentally friendly nature.In the present work,the latest progress in the research of transition-metal oxides is summarized.Moreover,the existing challenges are discussed,and a series of strategies are proposed to overcome these drawbacks.This review aims at providing guidance for the development of metal oxides in the next stage.

关键词： cathodes layered oxides oxygen reduction phase transition

Sustainable silicon anodes facilitated via a double-layer interface engineering: Inner SiOx combined with outer nitrogen and boron co-doped carbon

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Carbon Energy 2022年第3期4卷 399-410页

作者： Jun Zhou Yao Lu Lishan Yang Wenqiang Zhu weifang liu Yahui Yang Kaiyu liu Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Ministry of Education) National and Local Joint Engineering Laboratory for New Petrochemical Materials and Fine Utilization of ResourcesKey Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceHunan Normal UniversityChangshaHunanP.R.China College of Chemistry and Chemical Engineering Central South UniversityChangshaHunanP.R.China

Silicon-based(Si)materials are promising anodes for lithium-ion batteries(LIBs)because of their ultrahigh theoretical capacity of 4200 mA h g^(−1).However,commercial applications of Si anodes have been hindered by their drastic volume variation(∼300%)and low electrical conductivity.Here,to tackle the drawbacks,a hierarchical Si anode with double-layer coatings of a SiOx inner layer and a nitrogen(N),boron(B)co-doped carbon(C-NB)outer layer is elaborately designed by copyrolysis of Si-OH structures and a H3BO_(3)-doped polyaniline polymer on the Si surface.Compared with the pristine Si anodes(7mA h g^(−1) at 0.5 A g^(−1) after 340 cycles and 340 mA h g^(−1) at 5 A g^(−1)),the modified Si-based materials(Si@SiOx@C-NB nanospheres)present su perior cycling stability(reversible 1301 mA h g^(−1) at 0.5 A g^(−1) after 340 cycles)as well as excellent rate capability(690mA h g^(−1) at 5 A g^(−1))when used as anodes in LIBs.The unique double-layer coating structure,in which the inner amorphous SiOx layer acts as a buffer matrix and the outer defect-rich carbon enhances the electron diffusion of the whole anode,makes it possible to de liver excellent electrochemical properties.These results indicate that our double-layer coating strategy is a promising approach not only for the devel opment of sustainable Si anodes but also for the design of multielement-doped carbon nanomaterials.

关键词： boron-nitrogen co-doped carbon coating silicon anode stability wettability

Study of the Effect of Preoperative Dietary Intervention on Gastrointestinal Reaction of Microparticle TACE

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Journal of Clinical and Nursing Research 2023年第6期7卷 113-117页

作者： weifang liu Jingyi Lin Beijing Tsinghua Changgung Hospital Beijing 102218China

Objective:To evaluate the effect of preoperative dietary intervention on the gastrointestinal reaction of microparticle transcatheter arterial chemoembolization(TACE).Methods:A total of 60 patients with primary liver cancer who were treated in our hospital from January 2018 to October 2018 were selected for this study.The random sampling method was used to divide the patients into an intervention group(30 cases)and a control group(30 cases).The control group received routine intervention,whereas the intervention group received optimized nursing intervention.The incidence of gastrointestinal reactions,the vomiting frequency,the average vomiting volume,the incidence of stomach discomfort,the quality of life,and the anxiety and depression indicators of both groups were compared.Results:The results of all indicators of the intervention group were better than those of the control group.The incidence of gastrointestinal reactions in the intervention group was 13.9%,which was lower than 43.3%of the control group.The scores of QLQ-C30 of the intervention group were higher than those of the control group;the SAS and SDS scores in the intervention group were lower than those of the control group.Conclusion:Preoperative dietary intervention can reduce the incidence of gastrointestinal reactions of microparticle TACE and improve the symptoms of gastric discomfort among patients.

关键词： Microparticle TACE Dietary intervention Gastrointestinal reactions Quality of life Perioperative period

奥密克戎与甲型H1N1病毒性肺炎CT特征对比:初发及随访

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中国医学影像学杂志 2024年第3期32卷 250-254,262页

作者：刘韦芳曹煜晴刘敏民航总医院放射科北京100123 民航总医院急诊医学科北京100123 中日友好医院放射诊断科北京100029

目的比较新型冠状病毒奥密克戎变异株及甲型H1N1病毒性肺炎的CT影像特征,并探究影响两种肺炎吸收过程的相关因素。资料与方法回顾性收集2022年12月—2023年3月民航总医院奥密克戎病毒性肺炎影响43例(奥密克戎组)和甲型H1N1病毒性肺炎30... 详细信息

目的比较新型冠状病毒奥密克戎变异株及甲型H1N1病毒性肺炎的CT影像特征,并探究影响两种肺炎吸收过程的相关因素。资料与方法回顾性收集2022年12月—2023年3月民航总医院奥密克戎病毒性肺炎影响43例(奥密克戎组)和甲型H1N1病毒性肺炎30例(甲流组),对比两组患者的临床资料[年龄、性别、症状(有无发热)、症状持续时间,白细胞、单核细胞、淋巴细胞、中性粒细胞、C反应蛋白等]和初发及随访CT影像学特征[病变密度、分布、征象以及CT严重程度定性评分(CTSS)]。结果奥密克戎组平均年龄高于甲流组[(68.61±15.94)岁比(51.20±16.39)岁,P<0.0001],发热比率(58.1%比86.7%,P=0.009)和单核细胞计数[(0.40±0.16)比(0.58±0.19),P<0.0001]均低于甲流组。胸部CT显示奥密克戎组病灶分布以胸膜下为主,甲流组以胸膜下及沿支气管血管束分布为主(χ^(2)=8.592,P=0.035)。奥密克戎组较甲流组更易出现小叶间隔增厚(χ^(2)=11.753,P=0.001)、铺路石征(χ^(2)=16.216,P<0.0001)、充气支气管征(χ^(2)=16.216,P<0.0001)、胸腔积液(P=0.039)和胸膜增厚(χ^(2)=4.067,P=0.044),而甲流组比奥密克戎组更易出现结节影(χ^(2)=6.971,P=0.008)。奥密克戎组初发(Z=413,P=0.009)及随访CTSS评分(Z=107,P=0.027)均高于甲流组。奥密克戎组随访CTSS差值与初发CTSS相关性最强(r=0.689,P<0.0001)。甲流组随访CTSS差值与症状持续时间相关性最强(r=0.954,P<0.0001)。结论奥密克戎患者初发及随访病变范围均高于甲流患者,奥密克戎患者肺炎吸收程度可能与初发CTSS有关,而甲流患者可能与症状持续时间有关。

关键词： 2019冠状病毒性疾病流感病毒A型,H1N1亚型肺炎病毒感染多层螺旋计算机体层摄影术

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Rational design of nitrogen doped hierarchical porous carbon for optimized zinc-ion hybrid supercapacitors

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Nano Research 2019年第11期12卷 2835-2841页

作者： Penggao liu Yang Gao Yangyang Tan weifang liu Yanping Huang Jun Yan Kaiyu liu Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha410083China Key Laboratory of Energy Materials Chemistry Ministry of EducationKey Laboratory of Advanced Functional MaterialsAutonomous RegionInstitute of Applied ChemistryXinjiang UniversityXinjiang830046China College of Materials Science and Engineering Fuzhou UniversityFuzhou350108China

Aqueous rechargeable zinc-ion hybrid supercapacitors are considered to be a promising candidate for large-scale energy storage devices owing to their high safety,long life,and low price.In this paper,a nitrogen doped hierarchical porous carbon is evaluated as the cathode for aqueous rechargeable zinc-ion hybrid supercapacitors.Benefiting from the synergistic merits of excellent structural features of N-HPC and tiny zinc dendrite of Zn anode in ZnSO4 electrolyte,the zinc-ion hybrid supercapacitor exhibits excellent energy storage performance including high capacity of 136.8 mAh·g^−1 at 0.1·Ag^−1,high energy density of 191 Wh·kg^−1,large power density of 3,633.4 W·kg^−1,and satisfactory cycling stability of up to 5,000 cycles with a capacity retention of 90.9%.This work presents a new prospect of developing high-performance aqueous rechargeable zinc ion energy storage devices.

关键词： excellent performance zinc dendrite N-HPC zinc-ion Hybrid supercapacitors

Single-phase P2-type layered oxide with Cu-substitution for sodium ion batteries

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Journal of Energy Chemistry 2020年第4期29卷 148-154页

作者： Tao Chen weifang liu Yi Zhuo Hang Hu Maolan Zhu Ruizheng Cai Xinxin Chen Jun Yan Kaiyu liu Hunan Provincial Key Laboratory of Chemical Power Sources Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese ResourcesCollege of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083HunanChina School of Chemistry and Materials Longyan UniversityLongyan 364012FujianChina

The development of high-performance layered oxide cathodes for sodium ion batteries (SIBs) continues to facing be hindered by severe challenges to date.Herein,a single-phase P2-Na0.67Mn0.6Ni0.2Co0.1Cu0.1O2(NMNCC) comprising multiple-layer-oriented stacked nanoflakes is designed and synthesized via a simple sol-gel method.The large lattice parameters ensure a large three-dimensional frame,which enables the diffusion of sodium ions.Owing to its optimal morphology structure modulation transition metal substitution strategy,the MNCC electrode delivers a reversible capacity of 131.3 mAh g^-1 at 0.1 C with retention of 86.7%after 200 cycles.In addition,it provides an initial capacity of 86.7 mAh g^-1,and a retention of 80.0%after 500 cycles even at a current density of up to 1 A g^-1.The stable single-phase structure and slight volume shrinkage observed after Na+extraction further delay structural degradation.High Na+mobility and low Na+diffusion resistance are also guarantee the excellent rate performance of the NMNCC electrode.Thus,we determine that the NMNCC cathode is significant in the advancement of promising novel layered oxide cathodes.

关键词： Layered oxides Sodium-ion batteries Rate capability P2 structure

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中国口粮自给率的区域非均衡特征及空间收敛

资源科学 2024年第4期46卷 786-800页

作者：杨一单姚成胜高云鹏刘伟芳南昌大学经济管理学院南昌330031

【目的】从消费和需求两个角度探讨口粮安全的区域差异和空间敛散性,以期为各区域更好地承担口粮安全责任提供科学依据。【方法】本文以口粮自给率作为衡量口粮安全的标准,基于消费统计法测量2000—2020年中国省域口粮自给率,利用Dagum... 详细信息

【目的】从消费和需求两个角度探讨口粮安全的区域差异和空间敛散性,以期为各区域更好地承担口粮安全责任提供科学依据。【方法】本文以口粮自给率作为衡量口粮安全的标准,基于消费统计法测量2000—2020年中国省域口粮自给率,利用Dagum基尼系数及其分解方法考察全国及四大区域口粮自给率相对差异的大小、来源及演变态势,进一步应用Kernel密度估计及空间收敛分析其绝对差异分布的动态演进过程及空间敛散性特征。【结果】①2000—2020年全国口粮自给率呈三阶段上升,四大区域口粮自给率上升程度差异明显,上升程度总体呈现中部>东北>东部>西部的变化特征。②研究期内,东部及东北地区口粮自给率区域内差异显著扩大,中、西部地区略微扩大;区域间差异对全国口粮自给率区域差异的贡献率均值高达47.92%,远高于区域内差异20.38%的贡献率和超变密度31.71%的贡献率。③与西部地区不同,东部、中部和东北地区口粮自给率在分布形态和极化趋势上相似,表明研究期内三大区域内的绝对差异不断扩大,存在高低两极分化现象。④空间溢出效应情境下,全国和四大区域口粮自给率均存在显著的绝对β收敛和条件β收敛,口粮生产的各影响因素对区域口粮自给率条件收敛起着决定作用。【结论】中国整体口粮的绝对安全掩盖了区域口粮的不安全,但是未来口粮安全区域差异有缩小的可能。

关键词：口粮自给率粮食安全区域差异 Dagum基尼系数 Kernel密度估计空间收敛中国

Novel optical properties and induced magnetic moments in Ru-doped hybrid improper ferroelectric Ca3Ti2O7

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Journal of Advanced Ceramics 2021年第1期10卷 120-128页

作者： Xingxing WU Shouyu WANG Winnie WONG-NG Qiang GU Yao JIANG Chao WANG Shuang MA weifang liu Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology School of ScienceTianjin UniversityTianjin 300072China College of Physics and Material Science Tianjin Normal UniversityTianjin 300074China Materials Measurement Science Division National Institute of Standards and TechnologyGaithersburgMaryland 20899USA

Hybrid improper ferroelectric Ca3Ti2O7 and Ca3Tii 9RuO.iO7 ceramics were successfully synthesized by conventional solid-state reaction method.Two strongest diffraction peaks located around 2θ=33°shifted towards the lower angle region with Ru substitution,reflecting structure variation.Grain growth and higher oxygen vacancy concentration after doping resulted in a reduction in the coercive field about 20 kV/cm.Optical bandgap estimated by UV-vis diffuse reflectance(DR)spectrum and X-ray photoelectron spectroscopy(XPS)valence band spectra showed a decreasing trend due to the existence of impurity energy level upon Ru doping,which was consistent with the results of first-principles calculations.The origin of the unexpected induced magnetic moments in Ru-dope Ca3Ti2O7 is also discussed.

关键词： oxides electronic materials optical properties X-ray diffraction defects lectronic structure ferroelectricity

本钢2#连铸机设备升级改造中新技术的应用研究

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金属世界 2024年第3期 57-61页

作者：刘伟芳范育新本钢集团有限公司辽宁本溪117021

内容导读介绍了本钢炼钢厂2#连铸机通过设备改造后所采用的一系列新技术。这些技术包括塞棒控流系统、结晶器液压振动功能、倒角结晶器技术、结晶器液压调宽技术和扇形段辊列优化技术等。塞棒控流技术可以改善结晶器流场,提高钢水纯净度... 详细信息

内容导读介绍了本钢炼钢厂2#连铸机通过设备改造后所采用的一系列新技术。这些技术包括塞棒控流系统、结晶器液压振动功能、倒角结晶器技术、结晶器液压调宽技术和扇形段辊列优化技术等。塞棒控流技术可以改善结晶器流场,提高钢水纯净度;结晶器液压振动功能以及倒角结晶器技术提升了板坯表面实物质量;扇形段辊列优化技术有效地解决了包晶钢结晶器液面波动问题,同时,也提高了板坯的表面和内部质量。此外,通过结晶器液压调宽新技术的应用,本钢2#连铸机生产的品种结构得到了很好的拓展,可以稳定生产出对品质要求更高的品种钢,尤其是对表面质量和内部质量要求极为严格的汽车钢,使其更加适应市场的需求。

关键词：连铸机生产倒角结晶器液压调宽内部质量扇形段塞棒控流辊列