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Science Bulletin 2024年第5期69卷 601-605页

作者：许晶瑶李秋立路凯李献华 State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring(Ministry of Education) School of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Lunar basalts offer key insights into the magmatic and thermal evolution of the *** constraints deduced from the Apollo and Luna mission samples,as well as lunar meteorites,had previously suggested that lunar volcanism occurred as early as ca.≥4.37 billion years ago(Ga)[1]and ceased around 2.9-2.8 Ga[2],with two major pulses occurring in 3.95-3.58 and 3.38-3.08 Ga[3].But analysis of lunar basaltic samples recently returned by the Chang’e-5 mission reveals 2-billion-year-old volcanism on the Moon,representing the youngest lunar basalts reported to date[4,5].One of the most popular hypotheses for the cause of longlived volcanism on the Moon is that the source region for young lunar volcanism was enriched in radioactive heat-producing elements[2,6].Lunar samples from 3.5 to 3.0 Ga exhibit a gradual increase in the potassium,rare-earth elements,and phosphorus(KREEP)-like component contribution[3],consistent with the radioactive heat-producing elements ***,the demonstrably non-KREEP origin for the 2-billion-year-old Chang’e-5 basalts implies a possible transition in lunar volcanism away from a KREEP-like component contribution occurred between 3.0 and 2.03 Ga[7].Therefore,studying the characteristics and origin of magmatic activity during the period from 3.0 to2.03 Ga is essential to address the timing of the possible transition and to thus extend our understanding of sustaining long-lived volcanism on the ***,this goal is currently hampered by limited available lunar materials.

关键词： magmatic origin basalt

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碱式碳酸钇焙烧制备纳米Y_(2)O_(3)的工艺及动力学研究

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稀有金属与硬质合金 2024年第1期52卷 31-37页

作者：丘丽莉张魁芳刘志强广东省科学院资源利用与稀土开发研究所稀有金属分离与综合利用国家重点实验室广东省稀土开发及应用重点实验室广东广州510651 广东韶钢工程技术有限公司广东韶关512199

针对液相沉淀法制备纳米Y_(2)O_(3)粉体工艺的焙烧过程中粉体易团聚问题,以碳酸钠和碳酸氢钠混合沉淀剂沉淀获得的纳米碱式碳酸钇为对象,系统研究了其焙烧条件对Y_(2)O_(3)形貌和粒度的影响以及动力学行为。研究表明:在煅烧温度860℃、... 详细信息

针对液相沉淀法制备纳米Y_(2)O_(3)粉体工艺的焙烧过程中粉体易团聚问题,以碳酸钠和碳酸氢钠混合沉淀剂沉淀获得的纳米碱式碳酸钇为对象,系统研究了其焙烧条件对Y_(2)O_(3)形貌和粒度的影响以及动力学行为。研究表明:在煅烧温度860℃、升温速率5.375℃/min、焙烧时间1 h的条件下,得到D50=0.050μm,(D_(90)―D_(10))/(2D_(50))=0.98,分散性良好的纳米Y_(2)O_(3),其形貌与前驱体碱式碳酸钇相似。碱式碳酸钇前驱体(Y(OH)CO_(3)·H_(2)O)焙烧制备纳米Y_(2)O_(3)粉体的热分解过程分为两个阶段:第一阶段,Y(OH)CO_(3)·H_(2)O分解生成Y(OH)CO_(3),该反应过程的表观活化能E为90.23 kJ/mol,指前因子A为7.46×10^(5),反应级数n为0.75;第二阶段,Y(OH)CO_(3)分解生成Y_(2)O_(3),反应表观活化能E为236.55 kJ/mol,指前因子A为1.31×10^(11),反应级数n=0.82。

关键词：碱式碳酸钇前驱体纳米Y_(2)O_(3) 热分解焙烧动力学参数

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Unicyclic graphs with extremal Lanzhou index

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Applied Mathematics(A Journal of Chinese Universities) 2022年第3期37卷 350-365页

作者： liU Qian-qian li qiu-li ZHANG He-ping School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China

Very recently *** et al.[8]introduced a new topological index for a molecular graph G named Lanzhou index as∑_(u∈V(G))d_(u)d^(2)_(u),where d_(u)and d_(u)denote the degree of vertex u in G and in its complement *** index Lz(G)can be expressed as(n-1)M_(1)(G)-F(G),where M_(1)(G)and F(G)denote the first Zagreb index and the forgotten index of G respectively,and n is the number of vertices in *** turns out that Lanzhou index outperforms M_(1)(G)and F(G)in predicting the logarithm of the octanol-water partition coefficient for octane and nonane *** was shown that stars and balanced double stars are the minimal and maximal trees for Lanzhou index *** this paper,we determine the unicyclic graphs and the unicyclic chemical graphs with the minimum and maximum Lanzhou indices separately.

关键词： Lanzhou index unicyclic graph extremal graph Zagreb index forgotten index

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Hard-carbon hybrid li-ion/metal anode enabled by preferred mesoporous uniform lithium growth mechanism

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Journal of Energy Chemistry 2024年第1期88卷 252-259,I0006页

作者： Fang Yan Yan liu Yuan li Yan Wang Zicen Deng Meng li Zhenwei Zhu Aohan Zhou Ting li Jingyi qiu Gaoping Cao Shaobo Huang Biyan Wang Hao Zhang School of Chemistry and Biological Engineering University of Science and TechnologyBeijing 100083China Research Institute of Chemical Defense Beijing 100191China College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina National Base for International Science&Technology Cooperation School of ChemistryXiangtan UniversityXiangtan 411105HunanChina Materials and Manufacturing Department Beijing University of TechnologyBeijing 100124China

To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising *** particular,because of the anisotropy of graphite,hybrid anode formed by graphite/li metal has low transport kinetics and is easy to causes the growth of lithium dendrites and accumulation of dead li,which seriously affects the cycle life of batteries and even causes safety ***,by comparing graphite with two types of hard carbon,it was found that hybrid anode formed by hard carbon and lithium metal,possessing more disordered mesoporous structure and lithophilic groups,presents better *** indicate that the mesoporous structure provides abundant active site and storage space for dead *** the synergistic effect of this structure and lithophilic functional groups(–COOH),the reversibility of hard carbon/lithium metal hybrid anode is maintained,promoting uniform deposition of lithium metal and alleviating formation of lithium *** hybrid anode maintains a 99.5%Coulombic efficiency(CE)after 260 cycles at a specific capacity of 500 m Ah/*** work provides new insights into the hybrid anodes formed by carbon-based materials and lithium metal with high specific energy and fast charging ability.

关键词： Hard carbon/li metal hybrid anode Mesoporous structure Surface oxygen functional group Fast charging lithium batteries

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Pediatric acute heart failure caused by endocardial fibroelastosis mimicking dilated cardiomyopathy:A case report

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World Journal of Clinical Cases 2023年第8期11卷 1771-1781页

作者： Yao-Ying Xie qiu-li li Xin-Le li Fan Yang College of Clinical Medicine Inner Mongolia Minzu UniversityTongliao 028000Inner Mongolia Autonomous RegionChina Department of Pediatric Medical Center Soochow UniversityAffiliated Hulunbuir HospitalHulunbuir 021000Inner Mongolia Autonomous RegionChina College of Medicine Shantou UniversityShantou 515063Guangdong ProvinceChina School of Medicine Shihezi UniversityShihezi 832000Xinjiang Uygur Autonomous RegionChina

BACKGROUND Endocardial fibroelastosis(EFE)is a diffuse endocardial collagen and elastin hyperplasia disease of unknown etiology,which may be accompanied by myocardial degenerative changes leading to acute or chronic heart ***,acute heart failure(AHF)without obvious associated triggers is *** to the report of endomyocardial biopsy,the diagnosis and treatment of EFE are highly susceptible to being confounded with other primary ***,we report a case of pediatric AHF caused by EFE mimicking dilated cardiomyopathy(DCM),with the aim of providing a valuable reference for clinicians to early identify and diagnose EFE-induced *** SUMMARY A 13-mo-old female child was admitted to hospital with *** X-ray demonstrated enhanced texture in both lungs and an enlarged heart *** doppler echocardiography showed an enlarged left heart with ventricular wall hypokinesis and decreased left heart *** color ultrasonography revealed a markedly enlarged *** the result of the endomyocardial biopsy report,the child was treated with a variety of resuscitative measures including nasal cannula for oxygen,intramuscular sedation with chlorpromazine and promethazine,cedilanid for cardiac contractility enhancement,and diuretic treatment with ***,the child’s endomyocardial biopsy report result was confirmed as *** the above early interventions,the child’s condition gradually stabilized and *** week later,the child was *** a 9-mo follow-up period,the child took intermittent low-dose oral digoxin with no signs of recurrence or exacerbation of the heart *** Our report suggests that EFE-induced pediatric AHF may present in children over 1 year of age without any apparent precipitants,and that the associated clinical presentations are grossly similar to that of pediatric ***,it is still possible to be diagnosed effectively on the basis of the compr

关键词： Endocardial fibroelastosis Dilated cardiomyopathy Pediatric Acute heart failure Early identification and diagnosis

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Rapid screening of Zr-containing particles from Chang’e-5 lunar soil samples for isotope geochronology:Technical roadmap for future study

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Geoscience Frontiers 2022年第3期13卷 68-78页

作者： Jin-Hua li qiu-li li liang Zhao Jin-Hai Zhang Xu Tang li-Xin Gu Qian Guo Hong-Xia Ma Qin Zhou Yan liu Pei-Yu liu Hao qiu Gang li lin Gu Shun Guo Chun-Lai li Xian-Hua li Fu-Yuan Wu Yong-Xin Pan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Institute of High Energy Physics Chinese Academy of ScienceYuquan Road 19BShijingshan DistrictBeijing 100049China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

New samples returned by China Chang’e-5(CE-5)mission offer an opportunity for studying the lunar geologic longevity,space weathering,and regolith *** age determination of the CE-5 samples was among the first scientific questions to be ***,the precious samples,most in the micrometer size range,challenge many traditional analyses on large single crystals of zircon developed for massive bulk ***,we developed a non-destructive rapid screening of individual zirconium-containing particle for isotope geochronology based on a Micro X-ray fluorescence analysis(μXRF).The selected particles were verified via scanning electron microscopy(SEM),3D X-ray microscopy(XRM),and focused ion beam scanning electron microscopy(FIB-SEM)techniques,which showed that zirconium-bearing minerals with several microns were precisely positioned and readily suitable for site-specific isotopic dating by second ion mass spectrometry(SIMS).Such protocol could be also appli-cable in non-destructively screening other types of particles for different scientific *** there-fore proposed a correlative workflow for comprehensively studying the CE-5 lunar samples from single particles on nanometer to atomic *** various microscopic and spectromicroscopic instru-ments together,this workflow consists of six steps:(1)single-particle selection with non-destructive μXRF technique,(2)2D/3D morphological and structural characterization with a correlative submicron 3D XRM and nanoscale resolution FIB-SEM imaging methods,(3)SEM analysis of the surface morphology and chemistry of the selected particle,(4)a series of microscopic and microbeam analyses(e.g.,SEM,electron probe microanalysis,and SIMS)on the cross-section of the selected particle to obtain structural,mineralogical,chemical,and isotopic features from the micron to nanometer scale,(5)advanced 2D/3D characterization and site-specific sample preparation of thin foil/tip specimens on a microregion of inter-est in

关键词： Chang’e-5 lunar samples Zr-containing particles mXRF Correlative workflow Technical roadmap Extraterrestrial samples

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运用近红外光谱技术快速测定大青叶中靛玉红含量

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解放军药学学报 2024年第2期37卷 121-125页

作者：左春芳姚惠凤李秋莉宋燕妮联勤保障部队第989医院河南洛阳471000

目的运用近红外光谱技术快速测定大青叶中靛玉红含量,建立靛玉红的近红外定量分析模型,并通过模型分析评价大青叶的品质。方法采用传统的高效液相色谱法对74批大青叶中靛玉红含量进行测定及方法学验证,运用偏最小二乘法建立靛玉红含量... 详细信息

目的运用近红外光谱技术快速测定大青叶中靛玉红含量,建立靛玉红的近红外定量分析模型,并通过模型分析评价大青叶的品质。方法采用传统的高效液相色谱法对74批大青叶中靛玉红含量进行测定及方法学验证,运用偏最小二乘法建立靛玉红含量与近红外光谱之间的定量校正分析模型,并对验证集样品进行含量预测,将预测值与实际测定值进行统计分析。结果靛玉红浓度在1.04~3.13μg·ml^(-1)范围内线性良好,回归方程为Y=11566X+911.7,r=0.9990;精密度、重复性、12 h内稳定性的RSD分别为0.31%、0.86%、1.11%;加样平均回收率为99.22%。建立的定量分析模型准确性好,内部交叉验证均方差、内部交叉验证决定系数分别为0.226、0.983。通过对24份校正集样品进行外部验证,近红外预测值与高效液相测定值的预测回收率为93.66%。对两组数据进行方差显著性分析,其显著性指标值分别为0.540和0.428,表明两种试验方法的数据差异无统计学意义,该模型的精度和再现性均符合规定。结论近红外光谱技术对大青叶中靛玉红含量测定结果较好,建立的定量分析模型可以无损、快速、准确地对大青叶进行质量评价,提高生产效率。

关键词：近红外光谱技术大青叶靛玉红高效液相色谱法定量分析模型

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Unveiling the size effect of nitrogen-doped carbon-supported copper-based catalysts on nitrate-to-ammonia electroreduction

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Nano Research 2024年第4期17卷 2438-2443页

作者： Ran li Taotao Gao Wenxi qiu Minghao Xie Zhaoyu Jin Panpan li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Institute for Advanced Study Chengdu UniversityChengdu 610106China Materials Science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at AustinAustinTexas 78712USA Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

The electrocatalytic nitrate reduction reaction(NitRR)represents a promising approach toward achieving economically and environmentally sustainable ***,it remains a challenge to regulate the size effect of electrocatalysts to optimize the catalytic activity and ammonia ***,the Cu-based catalysts were tailored at the atomic level to exhibit a size gradient ranging from single-atom catalysts(SACs,0.15–0.35 nm)to single-cluster catalysts(SCCs,1.0–2.8 nm)and nanoparticles(NPs,20–30 nm),with the aim of studying the size effect for the NO_(3)^(-)-to-NH_(3) reduction ***,the Cu SCCs exhibit enhanced metal–substrate and metal–metal interactions by taking advantageous features of Cu SACs and Cu ***,Cu SCCs achieve exceptional electrocatalytic performance for the NitRR with a maximum Faradaic efficiency of ca.96%NH_(3)and the largest yield rate of ca.1.99 mg·h^(-1)·cm^(-2) at-0.5 V *** hydrogen electrode(RHE).The theoretical calculation further reveals the size effect and coordination environment on the high catalytic activity and selectivity for the *** work provides a promising various size-controlled design strategy for aerogel-based catalysts effectively applied in various electrocatalytic reactions.

关键词： nitrate electroreduction ammonia electrosynthesis size effect single-cluster catalyst

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Research on the stability of virtual coupling train formation based on a PID controller under the influence of time delay

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Transportation Safety and Environment 2024年第3期6卷 133-139页

作者： Sixuan qiu Ningzhou li Xiaojuan Wei Gaosong li School of Railway Transportation Shanghai Institute of TechnologyShanghai 201418China

As the latest research direction of train-to-train communication,virtual coupling train formation technology has attracted the attention of many *** paper studies the influence of time delay on the formation of virtual coupled *** proposed a distributed PID controller,which means that trains can still form a stable fleet operation under the influence of communication delay and control *** modelling and analysis,the research uses Matlab to conduct simulation,involving two sets of *** including speed,acceleration,position,position error,expected distance between adjacent trains and actual distance between adjacent trains are *** results demonstrate that the distributed PID controller can effectively control the impact of time delay on the virtual coupling fleet.

关键词： virtual coupling train-to-train communication time delay PID controller

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Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

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