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Chinese Chemical Letters 2024年第8期35卷 299-303页

作者： Guo-Ping Yin Ya-Juan Li Li Zhang ling-gao zeng Xue-Mei Liu Chang-Hua Hu Engineering Research Center of Coptis Development and Utilization(Ministry of Education) College of Pharmaceutical Sciences and Chinese MedicineSouthwest UniversityChongqing 400715China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 211198China NMPA Key Laboratory for Quality Monitoring of Narcotic Drugs and Psychotropic Substances Chongqing Institute for Food and Drug ControlChongqing 401121China

Citrinsorbicillin A(1),a novel homotrimeric sorbicillinoid,along with two new monomers citrinsor-bicillins B(2)and C(3),were isolated from the Coptis chinensis endophyte Trichoderma citrinoviride HT-9 by liquid chromatograph mass spectrometer(LC-MS)-guided strategy.1 was the first trimeric-example from terrestrial fungi,which possessed a unique carbon skeleton with two bicyclo[2.2.2]octanedione ring connected through an enolated carbon forming by[4+2]*** structures were elucidated by spectroscopic analysis and X-ray diffraction.1 exhibited moderate cytotoxicity against human colon cancer HT29 cells,and it induced significant cell cycle arrest by reducing the protein expression of cyclin D1.

关键词： Citrinsorbicillin A Trimeric sorbicillinoid Coptis chinensis endophyte Trichoderma citrinoviride [4+2]Cycloaddition Cytotoxic activity

Eigenvalues for the Clamped Plate Problem of L_(ν)^(2) Operator on Complete Riemannian Manifolds

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2223-2243页

作者： ling Zhong zeng Jiangxi Provincial Center for Applied Mathematics&School of Mathematics and Statistics Jiangxi Normal UniversityNanchang 330022P.R.China

L_(ν) operator is an important extrinsic differential operator of divergence type and has profound geometric *** this paper,we consider the clamped plate problem of L_(ν)^(2)operator on a bounded domain of the complete Riemannian manifolds.A general formula of eigenvalues of L_(ν)^(2) operator is *** this general formula,we obtain some estimates for the eigenvalues with higher order on the complete Riemannian *** several fascinating applications,we discuss this eigenvalue problem on the complete translating solitons,minimal submanifolds on the Euclidean space,submanifolds on the unit sphere and projective *** particular,we get a universal inequality with respect to the L_(II) operator on the translating ***,it is very difficult to get universal inequalities for weighted Laplacian and even Laplacian on the complete Riemannian ***,this work can be viewed as a new contribution to universal estimate.

关键词： Mean curvature flows L_(ν)^(2)operator clamped plate problem eigenvalues Riemannian manifolds translating solitons

A Convenient Method for the Stereoselective Synthesis of 7αHydroxycholesterol

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Chinese Chemical Letters 1998年第8期9卷 715-716页

作者： ling Jie gao and Tian zeng ZHAO Guang Dian HAN(The Institute of Chemistry, Henan Academy of Sciences, Zhengzhou, 450002)(Institute of Materia Medica, Peking Union Medical College,Chinese Academy of Medical Sciences, Beijing 100050) Institute of Chemistry Henan Academy of Sciences Zhengzhou 450002 China Institute of Materia Medica Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100050 China

7α-Hydroxycholesterol was prepared from cholesteryl acetate via allylic browhnation followed by hydroxylation in 73% overall yield.

关键词： 7α-hyrdoxycholesterol cholesteryl acetate stereoselective hydroxylation

Electrolyte effect on electrochemical behaviors of manganese fluoride material for aqueous asymmetric and symmetric supercapacitors

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Rare Metals 2024年第3期43卷 1048-1061页

作者： Zheng-Hua He Jian-Fei gao ling-Bin Kong State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou730050China

Exploring wide voltage window materials is not only an available measure to enhance the energy density of hybrid supercapacitor(HSCs),but also avoids the dynamic mismatch caused by different energy storage mechanisms of two electrodes in assembled symmetrical ***,there are few reports about the wide potential window materials except Bi_(2)O_(3)and VO_(2).Therefore,the MnF_(2)synthesized by solvothermal reaction was served as the electrode for *** MnF_(2)exhibited electrochemical activity in alkaline solution in three-electrode system,especially with a wide potential window from-0.8 to+0.5 V in 2 mol·L^(-1)***,the assembled MnF_(2)//MnF_(2)symmetrical HSC had a potential window of 1.5 V,and it exhibited outstanding long-cycle ***,when MnF_(2)was taken as the negative and positive respectively,the potential windows of asymmetric devices CoMoO_(4)//MnF_(2)and MnF_(2)//Activated Carbon(AC)could reach 1.3 and 1.45 V,respectively,showing excellent cycle *** work shows that MnF_(2)material has great research value in HSC,and provides a new research direction for developing high-performance devices.

关键词： Manganese fluoride Potential window Hybrid supercapacitors Electrochemical performance

Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response

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Nano-Micro Letters 2024年第10期16卷 453-473页

作者： Xiaojun zeng Xiao Jiang Ya Ning Yanfeng gao Renchao Che School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen 333403People's Republic of China School of Materials Science and Engineering Shanghai UniversityShanghai 200444People's Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People's Republic of China Zhejiang Laboratory Hangzhou 311100People's Republic of China

The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption ***,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not *** this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky *** skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching *** successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW *** detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal *** achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 *** cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth *** work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.

关键词： Semiconductor-semiconductor-metal heterostructure Semiconductor junctions Mott-Schottky junctions Built-in electric field Electromagnetic wave absorption

Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China

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China Geology 2024年第1期7卷 80-90页

作者： Ya-ying Wang ling-sen zeng Li-e gao Li-long Yan ling-hao Zhao Jia-hao gao Ying-long Di Guang-xu Li Yi-hong Tian Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China China Nonferrous Metals(Guilin)Geology and Mining Co. LtdGuilin 541004China

Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast *** are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation *** all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be ***“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(LIP),suggesting that they represent melts directly generated from the Kerguelen mantle ***“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative *** show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle *** their closely spatial and temporal relationship with the widespread Comei LIP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different *** weak enriched mafic rocks in Comei LIP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere *** process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous.

关键词： OIB type diabase Comei Large Igneous Province Weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume Geological survey engineering Tibet Plateau

Predicting the Mechanical Behavior of a Bioinspired Nanocomposite through Machine Learning

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1299-1313页

作者： Xingzi Yang Wei gao Xiaodu Wang Xiaowei zeng Department of Mechanical Engineering University of Texas at San AntonioSan AntonioTX78249USA Department of Mechanical Engineering Texas A&M UniversityCollege StationTX77843USA

The bioinspired nacre or bone structure represents a remarkable example of tough,strong,lightweight,and multifunctional structures in biological materials that can be an inspiration to design bioinspired high-performance *** bioinspired structure consists of hard grains and soft material *** the material interface has a very low volume percentage,its property has the ability to determine the bulk material *** learning technology nowadays is widely used in material science.A machine learning model was utilized to predict the material response based on the material interface properties in a bioinspired *** model was trained on a comprehensive dataset of material response and interface properties,allowing it to make accurate *** results of this study demonstrate the efficiency and high accuracy of the machine learning *** successful application of machine learning into the material property prediction process has the potential to greatly enhance both the efficiency and accuracy of the material design process.

关键词： Bioinspired nanocomposite computational model machine learning finite element material interface

Fe-Induced Electronic Transfer and Structural Evolution of Lotus Pod-Like CoNiFePx@P,N-C Heterostructure for Sustainable Oxygen Evolution

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Energy & Environmental Materials 2024年第3期7卷 186-193页

作者： Xiaojun zeng Qingqing Zhang Chulong Jin Hui Huang Yanfeng gao Advanced Ceramic Materials Research Institute School of Materials Science and EngineeringJingdezhen Ceramic University Singapore Institute of Technology School of Materials Science and Engineering Shanghai University

Transition metal phosphides with metallic properties are a promising candidate for electrocatalytic water oxidation,and developing highly active and stable metal phosphide-based oxygen evolution reaction catalysts is still ***,we present a facile ion exchange and phosphating processes to transform intestine-like CoNiPx@P,N-C into lotus pod-like CoNiFePx@P,N-C heterostructure in which numerous P,N-codoped carboncoated CoNiFePxnanoparticles tightly anchors on the 2D carbon ***,the as-prepared CoNiFePx@P,N-C enables a core-shell structure,high specific surface area,and hierarchical pore structure,which present abundant heterointerfaces and fully exposed active ***,the incorporation of Fe can also induce electron transfer in CoNiPx@P,IM-C,thereby promoting the oxygen evolution ***,CoNiFePx@P,IM-C delivers a low overpotential of 278 mV （vs RHE） at a current density of10 mA cm-1and inherits excellent long-term stability with no observable current density decay after 30 h of chronoamperometry *** work not only highlights heteroatom induction to tune the electronic structure but also provides a facile approach for developing advanced and stable oxygen evolution reaction electrocatalysts with abundant heterointerfaces.

关键词： electronic transfer Fe exchange multi-metal phosphides OER electrocatalysts structural evolution

Enabling the transfer matrix method to model serial-parallel compliant mechanisms including curved flexure beams

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International Journal of Mechanical System Dynamics 2024年第1期4卷 48-62页

作者： Mingxiang ling Lei Yuan Tingjun zeng Xianmin Zhang Robotics and Microsystems Center Soochow UniversitySoochowChina Guangdong Key Laboratory of Precision Equipment and Manufacturing Technology School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhouChina

Compliant mechanisms with curved flexure hinges/beams have potential advantages of small spaces,low stress levels,and flexible design parameters,which have attracted considerable attention in precision engineering,metamaterials,robotics,and so ***,serial-parallel configurations with curved flexure hinges/beams often lead to a complicated parametric ***,the transfer matrix method is enabled for analysis of both the kinetostatics and dynamics of general serial-parallel compliant mechanisms without deriving laborious formulas or combining other modeling ***,serial-parallel compliant mechanisms with curved flexure hinges/beams can be modeled in a straightforward manner based on a single transfer matrix of Timoshenko straight beams using a step-by-step *** and numerical validations on two customized XY nanopositioners comprised of straight and corrugated flexure units confirm the concise modeling process and high prediction accuracy of the presented *** conclusion,the present study provides an enhanced transfer matrix modeling approach to streamline the kinetostatic and dynamic analyses of general serial-parallel compliant mechanisms and beam structures,including curved flexure hinges and irregular-shaped rigid bodies.

关键词： compliant mechanisms curved flexure beams transfer matrix method nanopositioner rigid-body dynamics

Selective recovery of Th(Ⅳ) from radioactive rare earth waste residue by utilizing MoS_(2)-modified ion-absorbed type rare earth tailings

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Journal of Rare Earths 2024年第9期42卷 1782-1791,I0005页

作者： Xirong Chen Xinyu Fu Yun gao Zhiyuan zeng Bin Huang Xiaoqi Sun Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Fujian Research Center for Rare Earth Engineering Technology Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China Fujian College University of Chinese Academy of SciencesFuzhou350002China Jiangxi Province Key Laboratory of Cleaner Production of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhouJiangxi341000China

In the process of extracting ion-absorbed rare earth ore(IREO),the production of radioactive waste is a major environmental *** address this issue,MoS_(2) was used to modify ion-absorbed rare earth tailings(RET) to synthesize a novel MoS_(2)@RET composite material for the effective handling of radioactive waste generated in IREO separation *** composite material was thoroughly characterized using various analytical techniques,including X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),thermogravimetry(TG),Fourier-transform infrared(FTIR),scanning electron microscopy(SEM),Brunaue r-Emmett-Teller(BET) and energy dispersive spectroscopy(EDS).By optimizing the operating parameters,the optimal experimental conditions were determined to be pH=3,contact time=60 min,liquid-solid ratio=6 g/L,and initial concentration=150 mg/*** adsorption data fitted well with the pseudo second-order rate *** thermodynamic parameters concerning the adsorption of Th(Ⅳ) were analyzed and *** isotherm model is a more fitting choice for the adsorption process compared to the Freundlich isotherm ***_(2)@RET was used in the acid leachate of IREO waste residue,achieving the separation of Th and rare earth *** mechanism of Th(Ⅳ) adsorption by MoS_(2)@RET was investigated,revealing that the adsorption process involves electrostatic interactions,chemical bonding,and redox *** above research results indicate that MoS_(2)@RET composite materials have application potential in the sustainable treatment of IREO radioactive waste.

关键词： Rare earths Thorium Radioactive waste residue Adsorption Separation