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Chemical Research in Chinese Universities 2006年第6期22卷 688-691页

作者： LI Ya-feng z.ANG Li-mei WU lei-lei WANG Sheng-hai WANG Hai-lian SHANG Xuan-xuan College of Chemistry and Molecular Engineering College of Mathematics and Physics Qingdao University of Science ＆ Technology 266042 Qingdao P. R. China

A novel 12-ring network.coordination polymer, { [ Cu （ C4 N2 H10 ） 4 ]2 H4 V4 O14 } n （ denoted as QUST-4）, was hydrothermally synthesiz.d and structurally determined by X-ray single-crystal diffraction analysis. QUST-4 was crystalliz.d in a monoelinic system with space group P21/n. The parameters of the unit cell are a = 1. 0497（2） nm, b = 1.6728（3） nm, c=1.2857（3） nm, 3=94. 14（3）°, V=2.2517（8） nm^3, z.4, Dcal = 1.841 Mg/m^3, R1 = 0. 1071, and wR3 =0. 2703. The largest difference peak.and hole were 2284 and - 1040 c/nm^3, respectively. The SBU（ secondary building unit） of QUST-4 was a new cyclo- aggregate of polyoxovanadate cyelo-[ S4V4O14 ]^4 - , different from cyclo-[ V4O12 ]^4-, which was condensed from two tetrahedral and two trigonal bipyramids via ahernate arrangement. Cu（piper） 4 （ piper = piperaz.ne ） group connected the cyclo- [ H4 V4 O14 ] ^4 - anions to form the 12-ring network. The adjacent layers were link.d by van der Walls forces.

关键词： Coordination polymer Aggregate of polyoxovanadate Hydrothermal synthesis Network

New insights into plasmonic hot-electron dynamics

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Light(Science & Applications) 2024年第11期13卷 2427-2430页

作者： Dangyuan lei Dong Su Stefan A.Maier Department of Materials Science and Engineering Center for Functional Photonicsand Hong Kong Branch of National Precious Metals Material Engineering Research CentreCity University of Hong Kong83 Tat Chee AvenueHong Kong S.A.R.999077China School of Physics and Astronomy Monash UniversityClayton 3800 VICAustralia Black.tt Laboratory Imperial College LondonLondon SW72AZUK

Recent advances in understanding the hot-electron dynamics in plasmonic nanostructures have significantly impacted a variety of plasmonically powered physical,chemical,and even biological *** insights into their quant... 详细信息

关键词： dynamics plasmon insight

Evidence of guide field magnetic reconnection in flapping current sheets

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Earth and Planetary Physics 2024年第4期8卷 650-658页

作者： YunTian Hou SuPing Duan lei Dai Chi Wang State k.y Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China k.y Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Based on current sheet flapping motion on 27 August 2018 in the dusk.flank.magnetotail,as recorded by instruments aboard Magnetospheric Multiscale(MMS)spacecraft,we present the first study of guide field reconnection observed in the flux rope embedded in k.nk.lik. flapping current sheets near the dusk.side flank.of the *** more common magnetotail reconnections,which are symmetric,these asymmetric small-scale(λ_(i)~650 k.)reconnections were found in the highly twisted current sheet when the direction normal to the sheet changes from the z.direction into the Y *** unique feature of this unusual reconnection is that the reconnection jets are along the z.direction-different from outflow in the X direction,which is the more usual *** vertical reconnection jet is parallel or antiparallel to the up-and-down motion of the tail’s current *** normaliz.d reconnection rate R is estimated to be~*** results indicate that such asymmetric reconnections can significantly enlarge current sheet flapping,with large oscillation *** letter presents direct evidence of guide field reconnection in a highly twisted current sheet,characteriz.d by enlarged current sheet flapping as a consequence of the reconnection outflow.

关键词： magnetic reconnection magnetotail current sheet

A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics

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Journal of Rock.Mechanics and Geotechnical Engineering 2024年第6期16卷 2172-2183页

作者： Liang Wang Xue z.ang Jingjing Meng Qinghua lei Department of Earth Sciences ETH ZürichZürich8092Switzerland Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolL693BXUK Department of Civil Environmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleå97187Sweden Department of Earth Sciences Uppsala UniversityUppsala75105Sweden

In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated *** approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM *** mitigate the volumetric lock.ng issue in low-order elements,we employ a node-based strain smoothing *** discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the *** express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)***,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point ***,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM *** experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM *** work.holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics.

关键词： Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)

Analysis of k.y Technologies and Equipments Development of Largescale Melted Extrusion Manufacturing Systems

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Journal of Materials Science & Technology 2003年第z1期19卷 215-217页

作者： lei z.ANG Sheng CHEN Yongnian YAN Renji z.ANG Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China

To develop large-scale RP systems used to producing functional parts and large-siz.d models has become an urgentcall now. In this paper, a large-scale RP system, MEM600-l, based on the melted extrusion manufacturing (MEM)process has been developed successfully. And the k.y issues to develop such a system are discussed. Based on theactual forming experiment, it is concluded that the MEM600-l work. reliably and the forming efficiency is muchhigher than its parallel equipments.

关键词： Melted extrusion manufacturing, Large-scale RP systems, Forming efficiency

Human neuromuscular junction three-dimensional organoid models and the insight in motor disorders

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Journal of Molecular Cell Biology 2021年第11期13卷 767-773页

作者： k.jing z.ang lei Bai Wentao Xu Chengyong Shen Department of Neurobiology The First Affiliated HospitalInstitute of Translational MedicineSchool of MedicineZhejiang UniversityHangzhou 310020China

The neuromuscular junction(NMJ),a peripheral synaptic connection between motoneurons and sk.letal muscle fibers,controls *** of NMJs has been implicated in various motor *** of their large siz. and easy accessibility,NMJs have been extensively investigated in the neuroscience field and have greatly contributed to our understanding of the fundamental principles of synapses in the central nervous *** have tried multiple ways to develop models to recreate *** progress in the research and development of tissue-lik. organoids has made it possible to produce human NMJ three-dimensional(3D)models in vitro,providing an additional powerful strategy to study ***,we introduce the most recent advances of human embryonic stem cell-or induced pluripotent stem cell-derived organoids to model 3D NMJs.

关键词： neuromuscular junction organoid motor disorder

Separation and determination of acetyl-glutamine enantiomers by HPLC–MS and its application in pharmacok.netic study

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Journal of Pharmaceutical Analysis 2017年第5期7卷 303-308页

作者： Xiaoxiao z.ang lei Gao z.njian z.ang Yuan Tian k.y Laboratory of Drug Quality Control & Pharmacovigilance (China Pharmaceutical University) Ministry of Education State k.y Laboratory of Natural Medicine China Pharmaceutical University

A high-performance liquid chromatography coupled with mass spectrometry(HPLC–MS) method was established for the separation and determination of acetyl-glutamine enantiomers(acetylL-glutamine and acetylD-glutamine) simultaneously. Baseline separation was achieved on Chiralpak.AD-H column(250 mm ×4.6 mm, 5 μm). n-Hexane(containing 0.1% acetic acid) and ethanol(75:25, v/v) were used as mobile phase at a flow rate of 0.6 m L/min. The detection was operated in the negative ion mode with an ESI source. [M-H]-m/z.87.0540 for enantiomers and [M-H]-m/z.179.0240 for aspirin(IS) were selected as detecting ions. The linear range of the calibration curve for each enantiomer was 0.05–40 μg/m L. The precision of this method at concentrations of 0.5–20 μg/m L was within 7.23%, and the accuracy was 99.81%–107.81%. The precision at LOQ(0.05 μg/m L) was between 16.28% and 17.56%, which was poor than that at QC levels. The average extraction recovery was higher than 85% for both enantiomers at QC levels. The pharmacok.netics of enantiomers was found to be stereoselective. There was not chiral inversion in vivo or in vitro between enantiomers.

关键词： HPLC–MS Acetyl-glutamine Enantiomers separation Pharmacok.netics Chiral inversion

Design, Characteriz.tion, and 3D Printing of Cardiovascular Stents with z.ro Poisson’s Ratio in Longitudinal Deformation

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Engineering 2021年第7期7卷 979-990页

作者： Chengjin Wang lei z.ang Yongcong Fang Wei Sun Biomanufacturing Center Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Biomanufacturing and Rapid Forming Technology k.y Laboratory of Beijing Beijing 100084China “Biomanufacturing and Engineering Living Systems”Innovation International Talents Base(111 Base) Beijing 100084China Department of Mechanical Engineering Drexel UniversityPhiladelphiaPA 19104USA

Inherent drawback. associated with drug-eluting stents have prompted the development of bioresorbable cardiovascular *** manufacturing(3-dimentional(3D)printing)has been widely applied in medical *** this study,we develop a novel screw extrusion-based 3D printing system with a new designed mini-screw extruder to fabricate stents.A stent with a z.ro Poisson’s ratio(z.R)structure is designed,and a preliminary monofilament test is conducted to investigate appropriate fabrication parameters.3D-printed stents with different geometric structures are fabricated and analyz.d by observation of the surface *** evaluation of the mechanical properties and a preliminary biological evaluation of 3D-printed stents with different parameters are carried *** conclusion,the screw extrusion-based 3D printing system shows potential for customiz.ble stent fabrication.

关键词： Additive manufacturing 3D printing Screw extrusion Cardiovascular stent z.ro Poisson’s ratio

Effect of rotation curvature correction and inviscid spatial discretiz.tion scheme on the aerodynamics of vertical axis wind turbine

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Journal of Hydrodynamics 2024年第5期36卷 828-842页

作者： k.i-fang Ma Jia-song Wang lei-ping Xue School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai200240China MOE k.y Laboratory of Hydrodynamics Shanghai Jiao Tong UniversityShanghai200240China Yaz.ou Bay Institute of Deepsea Science and Technology Shanghai Jiao Tong UniversitySanya572024China

The effect of rotation-curvature correction and inviscid spatial discretiz.tion scheme on the aerodynamic performance and flow characteristics of Darrieus H-type vertical axis wind turbine(VAWT)are investigated based on an in-house *** solver is developed on an in-house platform HRAPIF based on the finite volume method(FVM)with the elemental velocity vector transformation(EVVT)*** present solver adopts the density-based method with a low Mach preconditioning *** turbulence models are the Spalart-Allmaras(SA)model and the k.ωshear stress transport(SST)*** inviscid spatial discretiz.tion schemes are the third-order monotone upstream-centered schemes for conservation laws(MUSCL)scheme and the fifth-order modified weighted essentially non-oscillatory(WENO-z.*** power coefficient,instantaneous torque of blades,blade wak.,and turbine wak. are compared and analyz.d at different tip speed *** extensive analysis reveals that the density-based method can be applied in VAWT numerical simulation;the SST models perform better than the SA models in power coefficient prediction;the rotation-curvature correction is not necessary and the third-order MUSCL is enough for power coefficient prediction,the high-order WENO-z.scheme can capture more flow field details,the rotation-curvature correction and high-order WENO-z.scheme reduce the length of the velocity deficit region in the turbine wak..

关键词： Rotation-curvature correction spatial discretiz.tion scheme turbulence model power coefficient wak.

Heading control method and experiments for an unmanned wave glider

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Journal of Central South University 2017年第11期24卷 2504-2512页

作者： LIAO Yu-lei LI Yi-ming WANG lei-feng LI Ye JIANG Quan-quan Science and Technology on Underwater Vehicle Laboratory Harbin Engineering UniversityHarbin 150001China

The control system designing of unmanned wave glider(UWG) is challenging since the control system is weak.maneuvering, large time-lag and large disturbance, which is difficult to establish accurate mathematical model. The control system for the "Ocean Rambler" UWG is studied in this work. A heading control method based on S-surface controller is designed. For the "rudder z.ro drift" problem in trials, an improved S-surface control method based on rudder angle compensation is proposed, which can compensate the adverse effects from environmental forces and installation error. The tank.test and sea trial results prove that the proposed control method has favorable control performance, and the feasibility and reliability of the designed control system are also verified.

关键词： unmanned wave glider heading control S-surface control control system