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A high-performance electromagnetic energy harvester for scavenging ultra-low frequency vibration energy of human foot movement

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Science China(Technological Sciences) 2024年第5期67卷 1391-1400页

作者： HU JiaJun QIAN Shuo wu Hui HU DongXu NIU LiXin BI XiaoXue ZHANG Jie HOU XiaoJuan GENG WenPing MU JiLiang HE Jian chou XiuJian Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan030051China School of Software North University of ChinaTaiyuan030051China

In our daily lives,low-frequency kinetic energy primarily manifests as vibrations.However,effective harnessing of lowfrequency kinetic energy remains a formidable challenge.This paper proposes a rope-driven rotor that rotates around an axis and consists of an ultra-high-molecular-weight polyethylene(UHMWPE)wire wrapped around a metal shaft.The rotor can convert ultra-low frequency vibration/linear motion into rapid rotation by pressing the top at low frequencies and driving the rope for a quick release.The harvester can generate up to 36.25 m W power using a 0.1-mm-diameter UHMWPE wire as the rotor when periodically pressed down to 20 mm at a frequency of 1 Hz.A simple power generation floor is assembled,generating 28.58-m W power with a matching load at a frequency of 1.5 Hz.Moreover,the harvester can increase the charging voltage of a 0.47-F supercapacitor from 0 to 6.8 V within 10 min.In addition,the harvester can harvest energy through a light finger press motion,and the energy obtained can also support the continuous operation of multiple electronic devices concurrently.This study introduces an effective method for harvesting ultra-low frequency energy and has great prospects in the field of power generation floor and human movement energy harvesting.

关键词： electromagnetic energy harvester rope-shaft coupling structure human motion ultra-low frequency

An air-stable single-crystal layered oxide cathode based on multifunctional structural modulation for high-energy-density sodium-ion batteries

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Science China Chemistry 2024年

作者： Yi-Feng Liu Hai-Yan Hu Jia-Yang Li Hongrui Wang Yi Zhao Jingqiang Wang Yuan-Bo wu Yan-Jiang Li Guang-Yu Zhang Qing-Qun Sun Yan-Fang Zhu Rui-Ren Tang Xiong-Wei wu Jia-Zhao Wang Shi-Xue Dou Shu-Lei chou Yao Xiao Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University School of Chemistry and Materials Science Hunan Agricultural University Institute of Energy Materials Science University of Shanghai for Science and Technology Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Institute for Carbon Neutralization College of Chemistry and Materials Engineering Wenzhou University College of Chemistry and Chemical Engineering Central South University

P2-type layered oxide, Na2/3Ni1/3Mn2/3O2, has drawn particular interest as a promising cathode material for sodium-ion batteries(SIBs) due to its fast sodium-ion transport channels with low migration potential. However, some catastrophic flaws, such as air instability, complicated multiphase evolution, and irreversible anionic redox, limit its electrochemical performance and hinder its application. Here, an air-stable single-crystal P2-type Na2/3Ni1/3Mn1/3Ti1/3O2is proposed based on the multifunctional structural modulation of Ti substitution that could alleviate the issues for practical SIBs. As a result, the cathode with high energy density shows excellent air stability and highly reversible phase transitions(P2–OP4), and delivers faster kinetics and stable anion redox chemistry. Meanwhile, a thorough investigation of the relationship between structure, function, and properties is demonstrated,emphasizing formation processes, electrochemical behavior, structural evolution, and air stability. Overall, this study provides the direction of multifunctional structural modulation for the development of high-performance sodium-based layered cathode materials for practical applications.

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Exceptional catalytic effect of novel rGO-supported Ni-Nb nanocomposite on the hydrogen storage properties of MgH_(2)

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Journal of Materials Science & Technology 2024年第5期172卷 83-93页

作者： Samuel Guemou Liuting Zhang Shuai Li Yiqun Jiang Tao Zhong Zichuan Lu Ren Zhou Fuying wu Qian Li School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China National Engineering Research Center for Magnesium Alloys&National Key Laboratory of Advanced Casting Technologies&College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Institute of New Energy Storage Materials and Equipment Chongqing 401135China Max Planck Institute for Iron Research Düsseldorf 40237Germany

The design of an excellent active catalyst to improve the sluggish kinetic and thermodynamic properties of magnesium hydride(MgH_(2))remains a great challenge to achieve its practical application.In this study,a novel Ni-Nb/rGO nanocomposite catalyst was successfully prepared by one-spot hydrothermal and sub-sequent calcination methods.The novel Ni-Nb/rGO nanocomposite exhibits an exceptional catalytic effect on improving MgH_(2) sorption properties.Specifically,the onset desorption temperature of MgH_(2)+10 wt%Ni-Nb/rGO composite is reduced to 198℃,much lower than that of undoped MgH_(2)(330℃).In-terestingly,the composite can release 5.0,5.9,and 6.0 wt%H_(2) within 10 min at 245,260,and 275℃,respectively.Furthermore,the dehydrogenated MgH_(2)+10 wt%Ni-Nb/rGO composite starts to absorb hydrogen even at room temperature with approximate 2.75 wt%H_(2) uptake at 75℃under 3 MPa H_(2) pressure within 30 min and exhibits excellent stability by maintaining 6.0 wt%hydrogen content after 20 cycles at 300℃.chou’s model suggests that the de/hydrogenation kinetics of Ni-Nb/rGO-modified MgH_(2) switches from surface penetration model to diffusion model at lower temperatures.Additionally,the ac-tivation energies(E a)for the de/hydrogenation of MgH_(2)+10 wt%Ni-Nb/rGO are reduced to 57.8 kJ/mol and 33.9 kJ/mol,which are significantly lower than those of undoped MgH_(2).The work demonstrates that the addition of a novel ternary Ni-Nb/rGO catalyst is an effective strategy to not only boost the sorption kinetics of MgH_(2) but also maintain its cycling property.

关键词： Hydrogen storage materials Magnesium hydride Ni-Nb/rGO Kinetic analysis Catalytic mechanism

Novel Biomass-derived Hollow Carbons as Anode Materials for Lithium-ion Batteries

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高等学校化学研究:英文版 2023年第2期39卷 283-289页

作者： wu Ziye LI Zifan chou Shulei LIANG Xiaoyu School of Measurement and Testing China Jiliang UniversityHangzhou310018China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

A novel hollow carbon derived from biomass lotus-root has been prepared by a one-step carbonization method.The carbon anode obtained at 900℃ showed the best electrochemical performance,corresponding to a high specific capacity of 445 mA·h/g at 0.1 C,as well as excellent cycling stability after 500 cycles.Further investigation exhibits that the lithium storage of hollow carbon involves Li^(+) adsorption in the defect sites and Li^(+) insertion.The results showed that the intrinsic structure of lotus root can inspire us to prepare biomass carbon with a hollow structure as an excellent anode for lithium-ion batteries.

关键词： Biomass hollow carbon Lithium-ion battery Negative electrode material Electrochemical performance

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白花败酱中三萜类化学成分研究

药学学报 2024年第4期59卷 1005-1009页

作者：吴其国黄乐怡陈志刘东风王永丽侴桂新安庆医药高等专科学校药学院安徽安庆246052 上海中医药大学中药研究所上海201203 上海中药标准化研究中心上海201203 中国医药工业研究总院上海医药工业研究院创新药物与制药工艺国家重点实验室上海201203 安庆食品药品检验中心安徽安庆246000

采用硅胶柱色谱、中压液相色谱、葡聚糖凝胶Sephadex LH-20柱色谱及制备液相色谱等多种色谱技术,从白花败酱95%乙醇提取物中分离得到7个三萜类化合物。根据化合物的理化性质和波谱数据确定了它们的结构,分别为29-乙酰氧基齐墩果酸-3-O-... 详细信息

采用硅胶柱色谱、中压液相色谱、葡聚糖凝胶Sephadex LH-20柱色谱及制备液相色谱等多种色谱技术,从白花败酱95%乙醇提取物中分离得到7个三萜类化合物。根据化合物的理化性质和波谱数据确定了它们的结构,分别为29-乙酰氧基齐墩果酸-3-O-α-L-阿拉伯糖苷(1)、齐墩果酸(2)、3β-羟基-24-降-乌苏-4(23),12(13),20(30)-三烯-28-酸(3)、3β-羟基-24-降-乌苏-4(23),12-二烯-28-酸(4)、熊果酸(5)、常春藤皂苷元(6)、齐墩果酸3-O-阿拉伯糖苷(7)。化合物1为新化合物,化合物3、4、6、7为首次从该植物中分离得到。通过对脂多糖(LPS)诱导的RAW 264.7细胞(小鼠单核巨噬细胞)释放的一氧化氮(NO)影响实验测定了化合物的抗炎活性,结果表明化合物1、2、3、4、6、7有显著抑制NO作用。

关键词：白花败酱三萜抗炎化学成分

基于时空最优低维动力系统的多尺度可压缩湍流数值模拟方法

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应用数学和力学 2024年第3期45卷 318-336页

作者：齐进吴锤结北京应用物理与计算数学研究所北京100088 大连理工大学力学与航空航天学院辽宁大连116024

按照周培源教授关于研究湍流数值模拟建模时必须分析和求解脉动速度场的思想,该研究基于第一性原理,系统地建立了基于时空低维最优动力系统的多尺度可压缩湍流数值模拟方法(LMS方法),并将其应用于多次冲击Richtmyer-Meshkov问题的数值... 详细信息

按照周培源教授关于研究湍流数值模拟建模时必须分析和求解脉动速度场的思想,该研究基于第一性原理,系统地建立了基于时空低维最优动力系统的多尺度可压缩湍流数值模拟方法(LMS方法),并将其应用于多次冲击Richtmyer-Meshkov问题的数值模拟中,首次得到了可压缩湍流的中尺度流场和不同于DNS近似解的湍流近似解.数值结果表明,LMS方法可以用较少的网格获得更精确的湍流近似解.首先解决了研究中遇到的几个问题,为LMS方法的构建铺平了道路.这些问题是:基于湍流的物理特性,提出了湍流大、中、小尺度分解的新概念;找到了box滤波空间相关性的计算方法;指出了湍流建模理论中长期存在的逻辑错误,提出了多尺度湍流模型的概念;讨论了湍流封闭问题的本质和关键,给出了克服湍流封闭问题的数值方法.采用box滤波方法/空间网格平均方法且在大尺度网格的意义下,LMS方法的本质是一种将RANS、LES、DES和DNS等湍流数值模拟方法统一的全新湍流数值模拟方法.需要指出的是,LMS方法也可以作为湍流模型研究的辅助工具,以检验SGS尺度方程/脉动方程中各项所对应的湍流模型是否正确.

关键词：周培源对湍流研究的开拓性贡献时空最优低维动力系统 LMS方法多尺度湍流模型可压缩湍流

Study on blood pressure rhythm in hypertensive patients with Yin deficiency syndrome and a random forest model for predicting hypertension with Yin deficiency syndrome

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Journal of Traditional Chinese Medicine 2024年第3期44卷 564-571页

作者： ZHOU Ying LI Ping LUAN Jianwei SHEN Rui wu Yinglan XU Qiwen WANG Xinyue ZHU Yao XU Xiangru LIU Zitian JIANG Yuning ZHONG Yong HE Yun JIANG Weimin Department of Cardiology the Affiliated Hospital of Nanjing University of Chinese MedicineJiangsu Province Hospital of Traditional Chinese Medicine Department of Health Management Centre Jinling HospitalAffiliated Hospital of Medical SchoolNanjing University Emergency Department Longhua HospitalShanghai University of Traditional Chinese Medicine Department of General Internal Medicine the Affiliated Hospital of Nanjing University of Chinese MedicineJiangsu Province Hospital of Traditional Chinese Medicine

OBJECTIVE: To investigate blood pressure rhythm(BPR)in Yin deficiency syndrome of hypertension(YDSH)patients and develop a random forest model for predicting YDSH.METHODS: Our study was consistent with technical processes and specification for developing guidelines of Evidence-based Chinese medicine clinical practice(T/CACM 1032-2017). We enrolled 234 patients who had been diagnosed with primary hypertension without antihypertensive medications prior to the enrollment. All participants were divided into Yin deficiency group(YX, n = 74) and non-Yin deficiency group(NYX, n = 160).Participants were professionally grouped by three experienced chief Traditional Chinese Medicine(TCM)physicians according to four examinations(i.e.,inspection, listening and smelling, inquiry and palpation).We collected data on 24 h ambulatory blood pressure monitoring(ABPM) and YDSH rating scale. We divided 24 h of a day into 12 two-hour periods [Chen-Shi(7:00-9:00), Si-Shi(9:00-11:00), wu-Shi(11:00-13:00), Wei-Shi(13:00-15:00), Shen-Shi(15:00-17:00), You-Shi(17:00-19:00), Xu-Shi(19:00-21:00), Hai-Shi(21:00-23:00), ZiShi(23:00-1:00), chou-Shi(1:00-3:00), Yin-Shi(3:00-5:00), Mao-Shi(5:00-7:00)] according to the theory of “midnight-midday ebb flow”. We used random forest to build the diagnostic model of YDSH, with whether it was Yin deficiency syndrome as the outcome. RESULTS: Compared with NYX group, YX group had more female participants with older age, lower waist circumference, body mass index(BMI), diastolic blood pressure(DBP), and smoking and drinking rate(all P < 0.05). The YDSH rating scores of YX group [28.5(21.0-36.0)] were significantly higher than NYX group [13.0(8.0-22.0)](P < 0.001), and the typical symptoms of YX group included vexing heat in the chest, palms and soles, dizziness, dry eyes, string-like and fine pulse, soreness and weakness of lumbus and knees, palpitations, reddened cheeks, and tinnitus(all P < 0.05). The ratio of non-dipper hypertension in YX group was higher than in NYX group(56.9% vs 44.4%, P = 0.004). Com

关键词： blood pressure rhythm blood pressure variability hypertension random forest Yin deficiency syndrome

Experimental investigation and thermodynamic assessment of La-Y-Ni ternary system in Ni-rich corner

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Rare Metals 2023年第4期42卷 1316-1331页

作者： Sheng-Xiang wu Li Wang Hui-Ping Yuan Qun Luo Qian Li Kuo-Chih chou State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China State Key Laboratory of Advanced Special Steels Shanghai Key Laboratory of Advanced FerrometallurgySchool of Materials Science and EngineeringShanghai UniversityShanghai200444China GRIMAT Engineering Institute Co. Ltd.Beijing101407China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing400044China

La-Y-Ni alloys exhibit high discharge capacity due to the formation of AB_(3-3.8)-type(A=La,Y;B=Ni)intermetallic compounds.However,the stable composition and temperature range for this type of phase are rarely reported,which restrains the development of La-Y-Ni hydrogen storage alloys with stable structure and high capacity.This paper focuses on the phase equilibria of the La-Y-Ni ternary system in Ni-rich corner.The phase constitution,microstructure,and equilibrated composition were experimentally determined at 1273 and 1148 K using X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy-dispersive spectroscopy(EDS).The solubilities of La and Y in the binary compounds were measured.Two ternary compounds,3R-LaY_(2)Ni_(9)with the structure of PuNi3 type and La_(0.5)Y_(0.5)Ni_(5)with the structure of CaCu5 type,existed at both temperatures.Based on the experimental data,the thermodynamic description of LaY-Ni system was assessed by Calculation of Phase Diagram method.The calculated isothermal sections agree with the experimental data.The thermodynamic database is helpful for the design of La-Y-Ni hydrogen storage alloys.

关键词： La-Y-Ni system Phase equilibria Calculation of Phase Diagram(CALPHAD) Isothermal section Phase transformation

Oldhamite:a new link in upper mantle for C-O-S-Ca cycles and an indicator for planetary habitability

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National Science Review 2023年第10期10卷 44-53页

作者： Yuegao Liu I-Ming chou Jiangzhi Chen Nanping wu Wenyuan Li Leon Bagas Minghua Ren Zairong Liu Shenghua Mei Liping Wang CAS Key Laboratory for Experimental Study under Deep-sea Extreme Conditions Institute of Deep-sea Science and Engineering Chinese Academy of Sciences Hainan Deep-Sea Technology Innovation Center Xi'an Center of Geological Survey China Geological Survey Department of Geoscience University of Nevada Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology

In the solar system,oldhamite(CaS) is generally considered to be formed by the condensation of solar nebula gas.Enstatite chondrites,one of the most important repositories of oldhamite,are believed to be representative of the material that formed Earth.Thus,the formation mechanism and the evolution process of oldhamite are of great significance to the deep understanding of the solar nebula,meteorites,the origin of Earth,and the C-O-S-Ca cycles of Earth.Until now,oldhamite has not been reported to occur in mantle rock.However,here we show the formation of oldhamite through the reaction between sulfide-bearing orthopyroxenite and molten CaCO3at 1.5 GPa/1510 K,0.5 GPa/1320 K,and 0.3 GPa/1273 K.Importantly,this reaction occurs at oxygen fugacities within the range of upper-mantle conditions,six orders of magnitude higher than that of the solar nebula mechanism.Oldhamite is easily oxidized to CaSO4or hydrolysed to produce calcium hydroxide.Low oxygen fugacity of magma,extremely low oxygen content of the atmosphere,and the lack of a large amount of liquid water on the celestial body’ s surface are necessary for the widespread existence of oldhamite on the surface of a celestial body otherwise,anhydrite or gypsum will exist in large quantities.Oldhamites may exist in the upper mantle beneath mid-ocean ridges.Additionally,oldhamites may have been a contributing factor to the early Earth’s atmospheric hypoxia environment,and the transient existence of oldhamites during the interaction between reducing sulfur-bearing magma and carbonate could have had an impact on the changes in atmospheric composition during the Permian-Triassic Boundary.

关键词： oldhamite middle-ocean ridge large igneous province Great Oxidation Event oxygen fugacity