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A Steroidal Glycoside from Cynanchum versicolor Bunge

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Chinese Chemical Letters 2006年第7期17卷 919-921页

作者： Zhao Guang ZHENG run hui liu Ling Yi KONG Wei Dong ZHANG Department of Phytochemistry Second Military Medical University Shanghai 200433 Departmentof Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210038 School of Pharmacy Shanghai Jiaotong University Shanghai 200030

A new C21 steroidal glycoside, named cynanversicoside F （1）, was isolated from the root of Cynanchum versicolor Bunge. Its structure was established as glaucogenin-A 3-O-β-D- digitoxopyranosyl-（1→4）-β-D-cymarop... 详细信息

关键词： Cynanchum versicolor C21 steroidal glycoside cynanversicoside F.

Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay

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China Ocean Engineering 2024年第1期38卷 144-155页

作者： LI hui-shan liu run YANG Xu LIAN Ji-jian State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Institute of Marine Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be *** this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil ***,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are *** results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ***,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure *** contact ratio hardly affects the horizontal bearing capacity of bucket ***,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than ***,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil *** comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations.

关键词： bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio

Antimicrobial Properties and Application of Polysaccharides and Their Derivatives

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Chinese Journal of Polymer Science 2021年第2期39卷 133-146,I0004页

作者： Gui-Xue Xia Yue-Ming Wu Yu-Fang Bi Kang Chen Wei-Wei Zhang Shi-Qi liu Wen-Jing Zhang run-hui liu State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237China Frontiers Science Center for Materiobiology and Dynamic Chemistry Key Laboratory of Specially Functional Polymeric Materials and Related Technology(ECUST)Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

With the quick emergence of antibiotic resistance and multi-drug resistant microbes,more and more attention has been paid to the development of new antimicrobial agents that have potential to take the ***,as one of the major classes of biopolymers,were explored for their antimicrobial properties and applications,owing to their easy accessibility,biocompatibility and easy *** and their derivatives have variable demonstrations and applications as antimicrobial agents and antimicrobial biomaterials.A variety of polysaccharides,such as chitosan,dextran,hyaluronic acid,cellulose,other plant/animal-derived polysaccharides and their derivatives have been explored for antimicrobial *** expect that this review can summarize the important progress of this field and inspire new concepts,which will contribute to the development of novel antimicrobial agents in combating antibiotic resistance and drug-resistant antimicrobial infections.

关键词： Antimicrobial Drug resistance Polysaccharides Polysaccharide derivatives Chitosan

Biofilm Disruption Utilizing α/β Chimeric Polypeptide Molecular Brushes

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Chinese Journal of Polymer Science 2019年第11期37卷 1105-1112页

作者： Si Zhang Xi-Mian Xiao Fan Qi Peng-Cheng Ma Wei-Wei Zhang Cheng-Zhi Dai Dan-Feng Zhang run-hui liu State Key Laboratory of Bioreactor Engineering Key Laboratory for Ultrafine Materials of Ministry of Education Research Center for Biomedical Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology

Gram-negative bacteria can cause serious infections and are well known problems in biomedical practices. Biofilms of gramnegative bacteria are notorious for their frequently encountered resistance toward antibiotics. We demonstrate that α/β chimeric polypeptide molecular brush (α/β CPMB) exerts potent activities against antibiotic-resistant gram-negative bacteria. MTT viability assay, bacterial colony counting, and live/dead staining all indicate that α/β CPMB not only inhibits biofilm formation of gram-negative Pseudomonas aeruginosa and Acinetobacter baumannii, but also effectively disrupts mature biofllms that are highly resistant to one of the most active antibiotics-colistin. The superior antibacterial performance of the α/β CPMB implies its potential topical applications in treating biofilms.

关键词： Molecular brush Chimeric polypeptide Biofilm Antimicrobial resistance Host defense peptide

Facile Synthesis of High Molecular Weight Polypeptides via Fast and Moisture Insensitive Polymerization of a-Amino Acid N-Carboxyanhydrides

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Chinese Journal of Polymer Science 2020年第10期38卷 1131-1140,I0007页

作者： Yue Ming Wu Wei-Wei Zhang Rui-Yi Zhou Qi Chen Chen-Yu Xie Heng-Xue Xiang Bin Sun Mei-Fang Zhu run-hui liu State KeyLaboratory of Bioreactor Enginering East China Uniersity of Science and TechnologyShanghai 200237China State Key Laboratory for Modification of Chemical Fibers and Polymer Materals College of Materias Science and EngineringDonghua UniversityShanghai 201620China Key Laboratory of Specally Functional Polymeric Materials and Related Technology(ECUST)Ministry of Education Key Laboratory for Ultrafine Materials of Ministry of EducationResearch Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Polypeptides have been widely utilized in the fields of biomaterials and *** since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare *** continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight *** address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal *** NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding *** can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does *** NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask.

关键词： NCA polymerization Polypeptide Open vessel Fast polymerization High Mw

Graphitic carbons:preparation,characterization,and application on K-ion batteries

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Rare Metals 2024年第9期43卷 4056-4075页

作者： Kang-Zhe Cao Jia-hui Ma Yu-Lian Dong Yu Duan run-Tian Zheng Dharani Bundhooa hui-Qiao liu Yong Lei College of Chemistry and Chemical Engineering Xinyang Normal UniversityXinyang 464000China Xinyang Key Laboratory of Low-Carbon Energy Materials Xinyang 464000China Fachgebiet Angewandte Nanophysik Institut fur Physik&IMN MacroNanoTechnische Universitat Ilmenau98693 IlmenauGermany Laboratory of Inorganic Materials Chemistry(CMI) University of NamurB-5000 NamurBelgium

K-ion batteries(KIBs)have drawn much attention due to the abundant potassium reserves and wide accessibility as well as high energy density,which can be designed for large-scale energy storage *** the most promising anode materials for KIBs,graphitic carbons,especially those with an intermediate structure between the crystalline graphite and amorphous carbons become a hot research focus because of the improved rate capability and enhanced diffusion-controlled capacity at low voltage ***,we first review the structures of graphitic carbons in the view of graphitic domains and the structure changes in their K-ion intercalation ***,we summarize the preparation mechanisms and characterizations of graphitic carbons and the influence factors in their degree of ***,we illustrate the strategies to optimize their K-ion storage properties from four aspects,namely graphitic domain design,microstructure engineering,electrochemical active component regulation,and defect ***,we propose the issues that urgently need to be solved in graphitic carbons and the possible *** hope that this view could offer some inspiration for the further designing and optimizing of graphitic carbons for practical KIBs.

关键词： Graphitic carbon K-ion battery Anode Graphite Structure design

Vibration attenuation performance of wind turbine tower using a prestressed tuned mass damper under seismic excitation

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 511-524页

作者： Lei Zhenbo liu Gang Wang hui hui Yi School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing 400045China

With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly *** particular,seismic excitation can create a resonance response and cause excessive vibration of the *** investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this ***,a mathematical model is established based on structural dynamics under seismic ***,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning ***,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal ***,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the *** addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.

关键词： wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation

Enlarged interlayer of separator coating enabling high-performance lithiumsulfur batteries

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 103-112页

作者： Yanqi Feng hui liu Xiaoting liu Qiongqiong Lu School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW) Dresden e.V.Dresden 01069Germany

Lithiumsulfur batteries have been intensively studied due to their high theoretical energy density and abundant sulfur resources. However, their commercial application is hindered by the low redox kinetics and high sulfur losses. In principle, in the design of cathodes and separators, the adsorption toward lithium-polysulfides should be enhanced and the conversion of soluble high-order lithium-polysulfides should be catalyzed. Herein, a KV_(3)O_(8)·0.75H_(2)O separator is designed as an effective lithium-polysulfides mediator in lithiumsulfur batteries. The intercalated K+ would enlarge the interlayer spacing of vanadium oxides, preventing the collapse of the layer structure and improving the electrical/ion conductivity of the interface. Moreover, the KV_(3)O_(8)·0.75H_(2)O modified separator possess a prior adsorption and high redox kinetics toward lithium-polysulfides due to the enhanced diffusion kinetics, which guarantees the high-rate capability and efficient utilization of sulfur. As a result, lithiumsulfur batteries exhibit a high capacity of 1362 mAh·g^(-1) and a long lifespan with a low capacity loss of 0.073% per cycle. This work may provide an alternative way to establish a functional separator to balance the adsorption and conversion of polysulfides during the redox back and forth.

关键词： lithium kinetics adsorption

An integrative mathematical model of microwave ion thruster for mHz-frequency thrust noise analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 121-136页

作者： Xiang NIU hui liu Daren YU Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

Many high-precision space missions need thrusters to produce thrust with low noise to compensate for disturbances and ensure satellite platform stability. Microwave ion thruster is characterized with a wide thrust range and potential for these missions. A cost-effective and accurate mathematical model is crucial for mHz-frequency thrust noise analysis and feedback controller design. The Particle-In-Cell(PIC) and global models are two common simulation tools. The PIC model is characterized with high accuracy but huge computation cost, which is difficult to analyze long-time performance characteristics. Now, the global model is only used for the discharge chamber with low accuracy and cannot reflect ion extraction properties. In this paper, an integrative mathematical model is built for a 1-cm microwave ion thruster and can reflect ion beamlet divergence and impingement on the Accelerator Grid(AG). Simulation results show good agreement with experiments at 0.06 sccm. However, the model demonstrates worse consistency with experiments when the flux increases to 0.1 sccm, which may be because the influence of neutral gas on the Electron Cyclotron Resonance(ECR) is not considered in the model. A long-time(1000 s) simulation is conducted with this model under 35 μN. It takes 3 hrs, and the thrust noise reaches 1 μN/Hz^(0.5) at 1 mHz.

关键词： Electric propulsion Microwave ion thruster Integrative model Sheath property Ion beamlet divergence Thrust noise Plasma