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Uncommon Bis-quinolizidine Alkaloids from the Hainan Sponge Neopetrosia chaliniformis

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Chinese Journal of Chemistry 2021年第7期39卷 1838-1842页

作者： Bao Chen xia-juan huan Ze-Hong Miao Nicole J.de Voogd Yu-Cheng Gu Chang-Yun Wang Yue-Wei Guo Xu-Wen Li Key Laboratory of Marine Drugs The Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdaoShandong266003 China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zu Chong Zhi RoadZhangjiang Hi-Tech ParkShanghai201203 China Open Studio for Druggability Research of Marine Natural Products Pilot National Laboratory for Marine Science and Technology(Qingdao)1 Wenhai RoadAoshanweiJimoQingdaoShandong266237 China Syngenta Jealott's Hill International Research CentreBracknellBerkshireRG426EY United Kingdom Naturalis Biodiversity Center P.O.Box 95172300 RALeidenthe Netherlands Leiden University Institute of Environmental SciencesP.O.Box 95182300 RALeidenthe Netherlands

Main observation and conclusion Two new bis-quinolizidine alkaloids,neopetrosiasins A(1)and B(2),possessing cis-and trans-quinolizidine nuclei,one known related analogue petrosin(3)and three known xestospongins(4-6),w... 详细信息

关键词： Sponge 1 Neopetrosia chaliniformis Alkaloids Configuration determination Cytotoxicity

Lagerindicine, a New Pyrrole Alkaloid Isolated from the Flowers of Lagerstroemia indica Linnaeus

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Natural Products and Bioprospecting 2021年第1期11卷 73-79页

作者： Yi Chen Song-Wei Li Fang-Zhou Yin Min Yang xia-juan huan Ze-Hong Miao xiao-Ming Wang Yue-Wei Guo State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zu Chong Zhi RoadZhangjiang Hi-Tech ParkShanghai 201203China Hunan Academy of Forestry 658 South Shao shan RoadChangsha 410004HunanChina Changsha Engineering Technology Research Center of Woody Flower 658 South shao shan RoadChangsha 410004HunanChina College of Materials Science and Engineering Central South University of Forestry and Technology498 South Shao shan RoadChangsha 410004HunanChina

A phytochemical investigation of the EtOH extract of the flowers of Lagerstroemia indica *** to the isolation and char-acterization of a new pyrrole alkaloid,named lagerindicine(1),along with four known compounds(2-5).Their structures were elucidated by the detailed spectroscopic analysis and comparison with literature data,whereas the structure,in par-ticularly,the absolute configuration(AC)of 1,was firmly determined by total *** the isolates were evaluated for their cytotoxic effects against human colon cancer cell(HCT-116),and compound 3 exhibited weak cytotoxicity with IC50 value of 28.4μM.

关键词： Lagerstroemia indica Linnaeus Pyrrole alkaloid Total synthesis Stereochemistry Cytotoxicity

Design and Synthesis of a Biomimetic Complex of Heme Ci

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Design and Synthesis of a Biomimetic Complex of Heme Ci

中国化学会第六届全国结构化学学术会议

作者： Yu Zhang,juan-xia Yang,huan Liu,Chuan-Jiang Hu~* Key Laboratory of Organic Synthesis of Jiangsu Province,College of Chemistry,Chemical and Materials Science,Soochow University,Suzhou 215123,P.R.China

Heme C is one special heme which has been discovered in cytochrome bf..It is a five-coordinate high-spin species with OH or HO as *** forms hydrogen bonding network with environment which is believed to play an important role in electron transfer and proton *** it function is unclear so far. Herein,we synthesized a model porphyrin,(5-(8-carbonyl-l-naphthyl)-10,15,20 -tri-p-tolylporphyrin),

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麦粒灸治疗哺乳期腱鞘炎的疗效观察

上海针灸杂志 2019年第11期38卷 1266-1269页

作者：高桂欢林志成夏焕娟杭州市西湖区文新街道社区卫生服务中心

目的观察麦粒灸治疗哺乳期腱鞘炎的临床疗效。方法 50例哺乳期腱鞘炎患者随机分为观察组和对照组,每组25例。观察组采用麦粒灸治疗,对照组采用封闭治疗。观察两组治疗前后及治疗后1个月Cooney腕关节评分、视觉模拟量表(VAS)评分变化,并... 详细信息

目的观察麦粒灸治疗哺乳期腱鞘炎的临床疗效。方法 50例哺乳期腱鞘炎患者随机分为观察组和对照组,每组25例。观察组采用麦粒灸治疗,对照组采用封闭治疗。观察两组治疗前后及治疗后1个月Cooney腕关节评分、视觉模拟量表(VAS)评分变化,并比较两组临床疗效。结果两组治疗后、治疗后1个月VAS评分均较治疗前降低(P0.05)。两组治疗后1个月VAS评分、Cooney腕关节评分、总有效率比较,差异有统计学意义(P<0.05)。结论麦粒灸治疗哺乳期腱鞘炎的近远期疗效显著,优于封闭治疗。

关键词：灸法麦粒灸疗法腱鞘炎哺乳期

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Efficient and Stable Photoassisted Lithium-Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Ma, Zelin Wang, Shiyao Ma, Zhuangzhuang Li, juan Zhao, Luomeng Li, Zhihuan Wang, Shiyuan Shuang, Yazhou Wang, Jiulong Wang, Fang xia, Weiwei Jian, Jie He, Yibo Wang, Junjie Guo, Pengfei Wang, Hongqiang Northwestern Polytech Univ Ctr Nano Energy Mat State Key Lab Solidificat Proc Sch Mat Sci & Engn Xian 710072 Peoples R China NPU Shaanxi Joint Lab Graphene Xian 710072 Peoples R China Northwestern Polytech Univ Sch Mat Sci State Key Lab Solidificat Proc Xian 710072 Peoples R China Northwestern Polytech Univ Engn Dept Xian 710072 Peoples R China Northwestern Polytech Univ Ctr Adv Lubricat & Seal Mat Sch Mat Sci & Engn State Key Lab Solidificat Proc Xian 710072 Peoples R China Northwestern Polytech Univ Shenzhen Res & Dev Inst Shenzhen 518063 Peoples R China Shaanxi Normal Univ Key Lab Appl Surface & Colloid Chem Shaanxi Engn Lab Adv Energy Technol Shaanxi Key Lab Adv Energy DevicesSch Mat Sci & E Xian 710119 Peoples R China

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries (PLIBs), while there is always a request on fast carrier transport in electrochemical active photocathodes. Present work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic nanocrystals. When employed in PLIBs, it was found effective for synchronously enhanced photocharge separation and transport in light charging process. Additionally, experimental photon spectroscopy, finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO2, as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky contact. Benefiting from these merits, several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set, including the capacity of 276 mAh g(-1 ) at 0.2 A g(-1 )under illumination, photoconversion efficiency of 1.276% at 3 A g(-1 ), less capacity and Columbic efficiency loss even through 200 cycles. These results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

关键词： Photoassisted lithium-ion batteries Bulk heterojunction Carrier dynamics TiO2 nanofiber Plasmonic metal nanocrystals

Fabrication and analysis of TIG welding-brazing butt joints of in-situ TiB2/7050 composite and TA2

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Defence Technology（防务技术） 2021年第3期17卷 1062-1070页

作者： huan-huan Sun Yi-bo Ren Yang Feng Hao-qiang Ba Dong Chen Chun-juan xia Hao-wei Wang School of Materials Science&Engineering Shenyang Ligong UniversityShenyangChina School of Materials Science&Engineering Shanghai Jiao Tong UniversityShanghaiChina

Lightweight hybrid structures of Al MMCs and titanium alloy dissimilar materials have great prospect in the defence industry application. So, it is necessary to join Al MMCs with Ti metal to achieve this structural design. In this work, in-situ Ti B_(2)/7050 composite and TA2 were firstly attempted to join by TIG welding-brazing technique. The result was that the intact welding-brazing butt joint was successfully fabricated. The joint presents dual characteristics, being a brazing on TA2 side and a welding on Ti B_(2)/7050 side. At brazing joint side, ER4043 filler metal effectively wets on TA2 under TIG heating condition,and a continuous interfacial reaction layer with 1 e3 mm is formed at welded metal/TA2 interface. The whole interfacial reaction layers are composed of Ti(Al Si)3 intermetallic compounds(IMCs), but their morphologies at the different regions present obvious distinguishes. The microhardness of the reaction layers is as much as 141 e190 HV. At welding joints side, the fusion zone appears the equixaed crystal structure, and the grain sizes are much smaller than those of welded metal, which is attributed to the effect of Ti B2 particulates from the melted Ti B_(2)/7050 on acceleration formation and inhibiting growth for the new crystal nucleus. The tensile test results show that average tensile strength of the optimal welding-brazing joint is able to achieve 138 MPa. The failure of the tensile joint occurs by quasi-cleavage pattern, and the cracks initiate from the IMCs layer at the groove surface of TA2 and propagate into the welded metal.

关键词： In-situ TiB2/7050 composite TA2 TIG welding-brazing Fabrication Analysis

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Effects of assembly errors and bonding defects on the centroid drift of a precision sleeve structure

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Advances in Manufacturing 2021年第4期9卷 509-519页

作者： Jian-Hua Liu xia-Yu Li huan-Xiong xia Lei Guo School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Adhesive joints are widely used in precision electromechanical products,and their bonding process has significant effects on the performance of an assembled *** paper presents a numerical study on the bonding assembly of a sleeve structure of a precision inertial device using a finite element method,where the stresses due to curing and relaxation behaviors are *** effects of assembly errors and bonding defects on the centroid drift of the sleeve structure were found and analyzed *** study can help understand the zero-drift mechanism of the precision inertial device and contribute valuable data for its error compensation.

关键词： Bonding process Adhesive joint Precision assembly Centroid drift

Variation of a signal in Schwarzschild spacetime

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Science China(Information Sciences) 2019年第8期62卷 172-191页

作者： huan LIU xiang-Gen xia Ran TAO School of Information and Electronics Beijing Institute of Technology Department of Electrical and Computer Engineering University of Delaware

In this paper, the variation of a signal in Schwarzschild spacetime is studied and a general equation for frequency shift parameter(FSP) is presented. The FSP is found to depend on the gravitationally modified Doppler effects and the gravitational effects of observers. In addition, the time rates of a transmitter and receiver may differ. When the FSP is a function of the receiver time, the FSP contributed through the gravitational effect(GFSP) or the gravitationally modified Doppler effect(GMDFSP) may convert a bandlimited signal into a non-bandlimited signal. Using the general equation, the FSP as a function of receiver time is calculated in three scenarios:(a) a spaceship leaving a star at constant velocity communicating with a transmitter at a fixed position;(b) a spaceship moving around a star with different conic trajectories communicating with a transmitter at a fixed position; and(c) a signal transmitted from a fixed position in a star system to a receiver following an elliptic trajectory in another star system. The studied stars are a Sun-like star, a white dwarf, and a neutron star. The theory is illustrated with numerical examples.

关键词： deep space communications general relativity Schwarzschild spacetime bandlimited signal gravitationally modified Doppler effect

Robust missile autopilot design based on dynamic surface control

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Journal of Systems Engineering and Electronics 2023年第1期34卷 160-171页

作者： ZHOU Jianping LI Wei xia Qunli JIANG huan School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Since the dynamical system and control system of the missile are typically nonlinear, an effective acceleration tracking autopilot is designed using the dynamic surface control(DSC)technique in order to make the missile control system more robust despite the uncertainty of the dynamical parameters and the presence of disturbances. Firstly, the nonlinear mathematical model of the tail-controlled missile is decomposed into slow acceleration dynamics and fast pitch rate dynamics based on the naturally existing time scale separation. Secondly, the controller based on DSC is designed after obtaining the linear dynamics characteristics of the slow and fast subsystems. An extended state observer is used to detect the uncertainty of the system state variables and aerodynamic parameters to achieve the compensation of the control law. The closed-loop stability of the controller is derived and rigorously analyzed. Finally, the effectiveness and robustness of the design is verified by Monte Carlo simulation considering different initial conditions and parameter uptake. Simulation results illustrate that the missile autopilot based DSC controller achieves better performance and robustness than the other two well-known *** method proposed in this paper is applied to the design of a missile autopilot, and the results show that the acceleration tracking autopilot based on the DSC controller can ensure accurate tracking of the required commands and has better performance.

关键词： acceleration autopilot nonlinear missile dynamics time-scale separation extended state observer dynamic surface control(DSC)

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