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Theoretical Analysis of the Buckling Behaviors of Inhomogeneous Shape Memory Polymer Composite Laminates Considering Prestrains

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Acta Mechanica Solida Sinica 2024年第2期37卷 271-284页

作者： Hanxing Zhao Pengyu Cao Fengfeng li Xin lan liwu liu Yanju liu Jinsong Leng Centre of Composite Materials and Structures Harbin Institute of Technology(HIT)Harbin150080China Department of Astronautical Science and Mechanics Harbin Institute of Technology(HIT)Harbin150001China

The mismatch in thermal expansion coefficients between the fiber-rich and resin-rich regions of a shape memory polymer composite(SMPC)laminate,along with the residual strain during SMPC fabrication,results in buckling deformation of the inhomogeneous *** paper presents a macroscopic model for buckling of an inhomogeneous SMPC laminate under initial biaxial *** linear and nonlinear buckling analyses are carried out using the energy *** influences of prestrain biaxiality,temperature,and ply angle on the buckling wavelength,critical buckling prestrain,and buckling amplitude are *** results demonstrate that the critical buckling wavelength of the SMPC laminate is independent of the prestrain,while the amplitude is almost independent of *** addition,the optimal fiber stacking configuration with the maximum critical buckling prestrains of inhomogeneous SMPC laminates is determined by a genetic algorithm.

关键词： Shape memory polymer composite Buckling behavior Inhomogeneous laminate Biaxial prestrains

Self assembled electron blocking and lithiophilic interface towards dendrite-free solid-state lithium battery

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Chinese Chemical Letters 2024年第4期35卷 220-225页

作者： Caixia li yi Qiu Yufeng Zhao Wuliang Feng Institute for Sustainable Energy&College of Sciences Shanghai UniversityShanghai 200444China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

The poor interfacial contact is one of the biggest challenges that solid-state lithium batteries suffer *** the solid-state electrolyte surface energy by transforming the interface from lithiophobic to lithiophilic is effective to promote the interfacial contact, but electronic conductive interphases usually increase the risk of electron attack, thus leading to uncontrollable li dendrite growth. Herein, we propose a self-assembled thermodynamic stable li I interphase to simultaneously improve the interfacial contact between the garnet electrolyte li_7La_(3)Zr_(2)O_(12)(LLZO) and li anode, and prohibit the electron attack. The direct contact between LLZO and li and the high temperature li melting process was ascribed to Zr4+reduction, which facilitated li dendrite formation and propagation. With the modification of the high lithiophilic I_(2) thin film, the area specific interfacial resistance of LLZO/li was reduced from 1525 Ω/cm^(2) to 57 Ω/cm^(2). More importantly, LLZO was protected from being reduced due to the outstanding electronic insulativity of the li I interphase, which leaded to a high critical current density of 1.2/7.0 m A/cm^(2) in the time/capacity-constant modes, respectively.

关键词： li_7La_(3)Zr_(2)O_(12) liI interphase Interfacial contact li dendrite Thermodynamic stable

Strain Gradient Finite Element Formulation of Flexoelectricity in Ferroelectric Material Based on Phase-Field Method

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Acta Mechanica Solida Sinica 2024年第4期37卷 570-579页

作者： Shuai Wang Hengchang Su Min yi li-Hua Shao National Key Laboratory of Strength and Structural Integrity Institute of Solid MechanicsSchool of Aeronautic Science and EngineeringBeihang UniversityBeijing100191People’s Republic of China State Key Laboratory of Mechanics and Control for Aerospace Structures and Institute for Frontier Science and Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education and College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China

Flexoelectricity is a two-way coupling effect between the strain gradient and electric field that exists in all dielectrics,regardless of point group ***,the high-order derivatives of displacements involved in the strain gradient pose challenges in solving electromechanical coupling problems incorporating the flexoelectric *** this study,we formulate a phase-field model for ferroelectric materials considering the flexoelectric effect.A four-node quadrilateral element with 20 degrees of freedom is constructed without introducing high-order shape *** microstructure evolution of domains is described by an independent order parameter,namely the spontaneous polarization governed by the time-dependent Ginzburg–landau *** model is developed based on a thermodynamic framework,in which a set of microforces is introduced to construct the constitutive relation and evolution *** the flexoelectric part of electric enthalpy,the strain gradient is determined by interpolating the mechanical strain at the node via the values of Gaussian integration points in the isoparametric *** model is shown to be capable of reproducing the classic analytical solution of dielectric materials incorporating the flexoelectric *** model is verified by duplicating some typical phenomena in flexoelectricity in cylindrical tubes and truncated pyramids.A comparison is made between the polarization distribution in dielectrics and *** model can reproduce the solution to the boundary value problem of the cylindrical flexoelectric tube,and demonstrate domain twisting at domain walls in ferroelectrics considering the flexoelectric effect.

关键词： Flexoelectricity Phase-field method Ferroelectrics Domain configuration

An environmentally sensitive zinc-selective two-photon NIR fluorescent turn-on probe and zinc sensing in stroke

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Journal of Pharmaceutical Analysis 2024年第4期14卷 578-584页

作者： Junfeng Wang Qibing liu yingbo li yi Pang Department of Chemistry The University of AkronAkronOH 44325USA Gordon Center for Medical Imaging Department of RadiologyMassachusetts General HospitalHarvard Medical SchoolBostonMA 02114USA Department of Pharmacy The First Affiliated Hospital of Hainan Medical UniversityHaikou570100China Engineering Research Center of Tropical Medicine Ministry of EducationHainan Medical UniversityHaikou571199China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing100191China Maurice Morton Institute of Polymer Science The University of AkronAkronOH 44325USA

A two-photon near infrared(NIR)fluorescence turn-on sensor with high selectivity and sensitivity for Zn^(2+)detection has been *** sensor exhibits a large Stokes'shift(-300 nm)and can be excited from 900 to 1000 nm,with an emission wavelength of-785 nm,making it ideal for imaging in biological *** sensor's high selectivity for Zn^(2+)over other structurally similar cations,such as Cd^(2+),makes it a promising tool for monitoring zinc ion levels in biological *** the high concentration of zinc in thrombi,this sensor could provide a useful tool for in vivo thrombus imaging.

关键词： Near-infrared Molecular imaging Thrombus Stroke

Efficient Metal Recovery from Industrial Wastewater:Potential Oscillation and Turbulence Mode for Electrochemical System

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Engineering 2024年第7期38卷 184-193页

作者： li Chen Gong Zhang Huijuan liu Shiyu Miao Qingbai Chen Huachun lan Jiuhui Qu Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

Efficient metal recovery from industrial wastewater facilitates addressing of the environmental hazards and resource requirements of heavy *** conventional electrodeposition recovery method is hampered by the limitations of interfacial ion transport in charge-transfer reactions,creating challenges for simultaneous rapid and high-quality metal ***,we proposed integrating a transient electric field(TE)and swirling flow(SF)to synchronously enhance bulk mass transfer and promote interfacial ion *** investigated the effects of the operation mode,transient frequency,and flow rate on metal recovery,enabling determination of the optimal operating conditions for rapid and efficient sequential recovery of Cu in TE&SF *** conditions included low and high electric levels of 0 and 4 V,a 50%duty cycle,1 kHz frequency,and 400 L·h^(-1)flow *** kinetic coefficients of TE&SF electrodeposition were 3.5-4.3 and 1.37-1.97 times that of single TE and SF electrodeposition,*** the deposition process under TE and SF conditions confirmed the efficient concurrence of interfacial ion transport and charge transfer under TE and SF synergy,which achieved rapid and highquality metal ***,the combined deposition strategy is considered an effective technique for reducing metal pollution and promoting resource recycling.

关键词： Ion transport Reaction kinetics Transient electric field Swirling flow

Dcalycinumines A-E,Alkaloids with Cytotoxic Activities of Nasopharyngeal Carcinoma Cells from Daphniphyllum calycinum

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Chinese Journal of Chemistry 2024年第1期42卷 35-42页

作者： Qing Tang Xiao-Yong Dai Qiang lin Zhi-Peng ling yi-Kun Hao Tian-Xi Zhu Ji-Hui Zhang yi-Bo Hou Yao-lan li Lai-Qiang Huang Jing-Hao Wang Guo-Cai Wang Yu-Bo Zhang Guangdong Clinical Translational Centerfor Targeted Drug Department of PharmacologySchoolof MedicineJinan University GuangzhouGuangdong 510632China Institute of Traditional Chinese Medicine&Natural Products Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchCollegeof PharmacyJinan UniversityGuangzhouGuangdong511443China Institute of Biopharmaceutical and Health Engineering Shenzhen Key Laboratory of Gene and Antibody TherapyState Key Laboratory of Chemical OncogenomicsShenzhen International Graduate SchoolTsinghua UniversityShenzhenGuangdong 518055China The Guangzhou Key Laboratoryof Basic and Translational Research on Chronic Disease Department of PharmacyThe First Affiliated HospitalJinan UniversityGuangzhouGuangdong 510630China

Fivenovel Daphniphyllum alkaloids,named dcalycinumines A-E(1-4,6),andeight previously described Daphniphyllum alkaloids(5,7-13)were isolated from Daphniphyllum *** 1 is the first Daphniphyllum alkaloid possessing a highly rearranged 6/6/6/7/5/6 hexacyclic architecture with a unique 3-methyl-1-azabicyclo[4,4,0]decane ring *** 2 represents a rare diamino Daphniphyllum alkaloid with an unprecedented 6/5/5/6/6/5 carbon skeleton featuring a unique 1-aza-6-azaspiro[4,5]decane unit,whereas 3 also represents a rare diamino Daphniphyllum alkaloid as a possible precursor of *** 4 is the second example of c-22-nor yuzurimine-type *** structures and absolute configurations were elucidated by HRESIMS,NMR spectroscopic analyses,EcD calculations,and single-crystal X-ray ***,compound 1 showed remarkable antitumor activities,which could inhibit the proliferation,migration and invasion of nasopharyngeal carcinoma cells,and promoted nasopharyngeal carcinoma cells apoptosis.

关键词： Daphniphyllum calycinum Natural products Daphniphyllum alkaloid Structural elucidation Biological activity Apoptosis Nasopharyngealcarcinoma

A data-driven model of drop size prediction based on artificial neural networks using small-scale data sets

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Chinese Journal of Chemical Engineering 2024年第2期66卷 71-83页

作者： Bo Wang Han Zhou Shan Jing Qiang Zheng Wenjie lan Shaowei li Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China State Key Laboratory of Chemical Engineering Tsinghua UniversityBeijing 100084China

An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data *** training,the deviation between calculate and experimental results are 3.8%and 9.3%,*** ANN model,the influence of interfacial tension and pulsation intensity on the droplet diameter has been *** size gradually increases with the increase of interfacial tension,and decreases with the increase of pulse *** can be seen that the accuracy of ANN model in predicting droplet size outside the training set range is reach the same level as the accuracy of correlation obtained based on experiments within this *** two kinds of columns,the drop size prediction deviations of ANN model are 9.6%and 18.5%and the deviations in correlations are 11%and 15%.

关键词： Artificial neural network Drop size Solvent extraction Pulsed column Two-phase flow Hydrodynamics

Failure evaluation and control factor analysis of slope block instability along traffic corridor in Southeastern Tibet

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Journal of Mountain Science 2024年第6期21卷 1830-1848页

作者： liU Changqing BAO Han lan Hengxing YAN Changgen li Changbo liU Shijie School of Highway Chang'an UniversityXi'an 710064China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The instability of slope blocks occurred frequently along traffic corridor in Southeastern Tibet(TCST),which was primarily controlled by the rock mass structures.A rapid method evaluating the control effects of rock mass structures was proposed through field statistics of the slopes and rock mass structures along TCST,which combined the stereographic projection method,modified M-JCS model,and limit equilibrium *** instabilities of slope blocks along TCST were then evaluated rapidly,and the different control factors of instability were *** showed that the probabilities of toppling(5.31%),planar(16.15%),and wedge(35.37%)failure of slope blocks along TCST increased *** instability modes were respectively controlled by the anti-dip joint,the joint parallel to slope surface with a dip angle smaller than the slope angle(singlejoint),and two groups of joints inclined out of the slope(double-joints).Regarding the control effects on slope block instability,the stabilization ability of doublejoints(72.7%),anti-dip joint(67.4%),and single-joint(57.6%)decreased sequentially,resulting in different probabilities of slope block ***,nearby regional faults significantly influenced the joints,leading to spatial heterogeneity and segmental clustering in the stabilization ability provided by joints to the slope ***,the stability of slope blocks gradually weakened as they approached the fault *** paper can provide guidance and assistance for investigating the development characteristics of rock mass structures and the stability of slope blocks.

关键词： Slope engineering Block instability Rapid evaluation method Rock mass structure Control factor

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang li Yu liu Xiao-Xiao ling li-Guang Wu li Yang lan Yang Bo Yang Yong-Gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo