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Numerical Mathematics(Theory,Methods and Applications) 2013年第1期6卷 1-20页

作者： Huibin chang Xue-Cheng Tai School of Mathematical Sciences Tianjin Normal UniversityTianjin 300387 Department of Mathematics East China Normal UniversityShanghai 200241China Department of Mathematics University of BergenJohaness Brunsgate 12Bergen 5007Norway

In this paper,we propose a generalized penalization technique and a convex constraint minimization approach for the p-harmonic flow problem following the ideas in[Kang&March,IEEE *** Process.,16(2007),2251–2261].We use fast algorithms to solve the subproblems,such as the dual projection methods,primal-dual methods and augmented Lagrangian *** a special penalization term,some special algorithms are *** experiments are given to demonstrate the performance of the proposed *** successfully show that our algorithms are effective and efficient due to two reasons:the solver for subproblem is fast in essence and there is no need to solve the subproblem accurately(even 2 inner iterations of the subproblem are enough).It is also observed that better PSNR values are produced using the new algorithms.

关键词： p-harmonic flows denoising generalized penalization terms saddle-point problem image processing augmented Lagrangian methods

Organic functional materials based buffer layers for efficient perovskite solar cells

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Chinese Chemical Letters 2017年第3期28卷 503-511页

作者： Fateh Ullah Hongzheng Chen chang-Zhi Li moe Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

In this review, we highlight the recent development of organic π-functional materials as buffer layers in constructing efficient perovskite solar cells（PVSCs）. By following a brief introduction on the PVSC development, device architecture and material design features, we exemplified the exciting progresses made in field by exploiting organic π-functional materials based hole and electron transport layers（HTLs and ETLs） to enable high-performance PVSCs.

关键词： Perovskite solar cells Organic functional material Hole transport layer Electron transport layer Power conversion efficiency

Screening of plane S waves by an array of rigid piles in poroelastic soil

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 589-599页

作者： Yuan-qiang CAI Guang-ya DING chang-jie XU moe Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang Universiry Hangzhou 310027 China College of Architecture and Civil Engineering Wenzhou University Wenzhou 325035 China

An array of rigid piles used as a screening barrier for plane shear (S) waves is investigated in a homogeneous unbounded space. The dynamic poroelastic theory of Biot is employed, under the assumption of an incompressible solid grain. Using Fourier-Bessel series, the problem of multiple scattering is solved by imposing continuity conditions and equilibrium conditions at the soil-pile interfaces with the translational addition theorem. A parametric analysis is conducted to investigate the influence of the permeability of poroelastic soil, separation between piles, number of piles and frequency of incident waves on screening effectiveness of the barrier, and the results are compared with those in an elastic soil medium. Computed results show that the intrinsic permeability of the soil medium displays an apparent effect on the screening of plane S waves.

关键词： Array of rigid piles Poroelastic soil Theory of Biot Scattering Screening effectiveness

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菊资源国内外专利布局现状与开发利用策略

中草药 2024年第8期55卷 2800-2811页

作者：韦诗冰常相伟吴德玲宿树兰严辉魏丹丹彭代银安徽中医药大学药学院安徽合肥230012 省部共建安徽道地中药材品质提升协同创新中心安徽合肥230012 安徽省中医药科学院药物制剂研究所安徽合肥230012 药物制剂技术与应用安徽省重点实验室安徽合肥230012 现代药物制剂安徽省工程技术研究中心安徽合肥230012 南京中医药大学江苏省中药资源产业化过程协同创新中心江苏南京210023

我国菊资源丰富,花序为其主要药用部位,其种植、采收过程的茎叶及根等非药用部位常被废弃。菊非药用部位同样含有丰富的资源性化学成分,具有多种药理作用,开发利用前景广阔。以国家知识产权局专利数据库和Patsnap专利数据库为数据源,对... 详细信息

我国菊资源丰富,花序为其主要药用部位,其种植、采收过程的茎叶及根等非药用部位常被废弃。菊非药用部位同样含有丰富的资源性化学成分,具有多种药理作用,开发利用前景广阔。以国家知识产权局专利数据库和Patsnap专利数据库为数据源,对菊资源国内外专利进行系统整理分析,从发展趋势、全球分布、申请人构成、技术领域、技术生命曲线、技术生长率及专利质量等多个角度阐述菊资源当前专利的活动特征,揭示菊资源产业发展态势及资源化利用现状。在此基础上,进一步系统梳理菊花及菊非药用部位资源性化学成分特点及其潜在资源价值,并基于循环经济发展理念提出精细高值化、转化增效、粗放低值化及文旅融合特色化的菊资源多元化开发利用策略与途径,为提升菊资源利用效率,延伸菊资源经济产业链,推动碳达峰、碳中和目标实现提供研究思路和理论依据。

关键词：菊菊花资源专利布局非药用部位开发利用策略

The Influence of Crystallographic Orientation and Grain Boundary on Nanoindentation Behavior of Inconel 718 Superalloy Based on Crystal Plasticity Theory

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 385-396页

作者： Wenbo Zhu Guangjian Yuan Jianping Tan Shuai chang Shantung Tu moe Key Laboratory of Pressure Systems and Safety East China University of Science and TechnologyShanghai 200237China

The crystal plasticity finite element method(CPFEM)is widely used to explore the microscopic mechanical behavior of materials and understand the deformation mechanism at the ***,few CPFEM simulation studies have been carried out to analyze the nanoindentation deformation mechanism of polycrystalline materials at the microscale *** this study,a three-dimensional CPFEM-based nanoindentation simulation is performed on an Inconel 718 polycrystalline material to examine the influence of different crystallographic parameters on nanoindentation behavior.A representative volume element model is developed to calibrate the crystal plastic constitutive parameters by comparing the stress-strain data with the experimental *** indentation force-displacement curves,stress distributions,and pile-up patterns are obtained by CPFEM *** results show that the crystallographic orientation and grain boundary have little influence on the force-displacement curves of the nanoindentation,but significantly influence the local stress distributions and shape of the pile-up *** the difference in crystallographic orientation between grains increases,changes in the pile-up patterns and stress distributions caused by this effect become more *** addition,the simulation results reveal that the existence of grain boundaries affects the continuity of the stress *** obstruction on the continuity of stress distribution increases as the grain boundary angle *** research demonstrates that the proposed CPFEM model can well describe the microscopic compressive deformation behaviors of Inconel 718 under nanoindentation.

关键词： Crystal plasticity Grain boundary Crystallographic orientation Nanoindentation

Dielectric loss enhancement induced by the microstructure of CoFe_(2)O_(4) foam to realize broadband electromagnetic wave absorption

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1388-1397页

作者： Bin Shi Hongsheng Liang Zijun Xie Qing chang Hongjing Wu College of Chemistry and Chemical Engineering Shaanxi Key Laboratory of Chemical Reaction EngineeringYan’an UniversityYan’an 716000China moe Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072China

CoFe_(2)O_(4)has been widely used for electromagnetic wave absorption owing to its high Snoek limit,high anisotropy,and suitable saturation magnetization;however,its inherent shortcomings,including low dielectric loss,high density,and magnetic agglomeration,limit its application as an ideal *** study investigated a microstructure regulation strategy to mitigate the inherent disadvantages of pristine CoFe_(2)O_(4)synthesized via a sol–gel auto-combustion method.A series of CoFe_(2)O_(4)foams(S0.5,S1.0,and S1.5,corresponding to foams with citric acid(CA)-to-Fe(NO_(3))_(3)·9H_(2)O molar ratios of 0.5,1.0,and 1.5,respectively)with two-dimensional(2D)curved surfaces were obtained through the adjustment of CA-to-Fe^(3+)ratio,and the electromagnetic parameters were adjusted through morphology *** to the appropriate impedance matching and conductance loss provided by moderate complex permittivity,the effective absorption bandwidth(EAB)of S0.5 was as high as 7.3 GHz,exceeding those of most CoFe_(2)O_(4)-based ***,the EAB of S1.5 reached 5.0 GHz(8.9–13.9 GHz),covering most of the X band,owing to the intense polarization provided by lattice defects and the heterogeneous *** three-dimensional(3D)foam structure circumvented the high density and magnetic agglomeration issues of CoFe_(2)O_(4)nanoparticles,and the good conductivity of 2D curved surfaces could effectively elevate the complex permittivity to ameliorate the dielectric loss of pure CoFe_(2)O_(4).This study provides a novel idea for the theoretical design and practical production of lightweight and broadband pure ferrites.

关键词： CoFe_(2)O_(4)foam lightweight broadband absorption microstructure regulation dielectric loss

MULTILAYERS AND POLY(ALLYLAMINE HYDROCHLORIDE)-GRAFTPOLY(ETHYLENE GLYCOL) MODIFIED BOVINE SERUM ALBUMIN NANOPARTICLES:IMPROVED STABILITY AND pH-RESPONSIVE DRUG DELIVERY

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Chinese Journal of Polymer Science 2012年第5期30卷 719-726页

作者： Li-li Xie 仝维鋆 Jian-quan Xu chang-you Gao moe Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

To improve the colloidal stability of bovine serum albumin （BSA） nanoparticles （hiPs） in diverse mediums, poly（allylamine hydrochloride）（PAH）/sodium poly（4-styrene sulfonate）（PSS） multilayers and poly（allylamine hydrochloride）-graft-poly（ethylene glycol）（PAH-g-PEG） coating were coated on the surface of BSA NPs. Stabilities of the BSA NPs in diverse mediums with different surfaces were detected by dynamic light scattering （DLS）. Multilayers and PAH-g-PEG coated BSA NPs can be well dispersed in various mediums with a narrow polydispersity index （PDI）. The BSA NPs with the highest surface density of PEG show the best stability. The multilayers and PAH-g-PEG coating do not deter the pH-dependent loading and release property of BSA NPs. At pH 9, the encapsulation efficiency of doxorubicin reaches almost 99%, and the release rate at pH 5.5 is significantly higher than that at pH 7.4.

关键词： BSA nanoparticle PEG LBL Drug delivery pH-responsive.

Error evaluation of binocular vision method for reconstructing breaking wave surface

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Journal of Hydrodynamics 2022年第5期34卷 970-974页

作者： Qian Wang Hao-cheng Lu chang-ze Zhao Hua Liu Department of Engineering Mechanics Shanghai Jiao Tong UniversityShanghai200240China Key Laboratory of Hydrodynamics(moe) Shanghai Jiao Tong UniversityShanghai200240China

Quantization error and its source of the binocular stereo vision technique are evaluated by measuring breaking wave surface in wave *** verification test focuses on the run-up process of a breaking solitary wave on a *** three-dimensional topography of the free surface is reconstructed at three representative stages of wave *** two-dimensional profile from the side view and statistical data are used to evaluate the quantization *** breaking degree of wave surface has a mild influence on the performance of stereo reconstruction in the current *** mean error of detecting the surface elevation is about 2 mm,around 0.1%of the measurement *** percent of the error comes from the deficient match in image interrogation,and the remaining forty percent arises from the limited system *** precise stereo measurement of the breaking surface shows that the present binocular vision system provides a new technique in experiments in hydrodynamics with the breaking surface.

关键词： Binocular stereo reconstruction surface deformation breaking wave image processing

Parameter effects on the dynamic characteristics of a super-long-span triple-tower suspension bridge

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 305-316页

作者： Hao WANG Ke-guan ZOU Ai-qun LI chang-ke JIAO College of Civil Engineering Southeast University Nanjing 210096 China

A 3D finite element model for the Taizhou Yangtze River Bridge,the first triple-tower long-span suspension bridge in China,is established based on the nonlinear finite element software ABAQUS,and the dynamic characteristics of the bridge are analyzed using the LANCZOS eigenvalue solution method. The study focuses on the effects of the vertical,lateral and torsional stiffness of the steel box girder,the rigid central buckle and the elastic restraints connecting the towers and the steel box girder on the dynamic characteristics of the triple-tower suspension bridge. Our results show that,in general,the dynamic characteristics of the triple-tower suspension bridge are similar to those of two-tower suspension bridges. The vertical,lateral and torsional stiffness of the steel box girder have different effects on the dynamic characteristics of triple-tower suspension bridges. The elastic re-straints have a more significant effect on the dynamic characteristics than the central buckle,and decreasing the stiffness of the elastic restraints results in the appearance of a longitudinal floating vibration mode of the bridge. Also,rigid central buckles have a greater influence on the dynamic characteristics of triple-tower suspension bridges than on those of two-tower suspension bridges. The results obtained could serve as a valuable numerical reference for analyzing and designing super-long-span triple-tower suspension bridges.

关键词： Suspension bridge Taizhou Bridge Triple-tower Dynamic characteristics Super-long-span

A 2.5D finite element approach for predicting ground vibrations generated by vertical track irregularities

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 885-894页

作者： Xue-cheng BIAN chang CHAO Wan-feng JIN Yun-min CHEN moe Key Laboratory of Soft Soils and Geoenvironmental Engineering Department of Civil Engineering Zhejiang University Hangzhou 310058 China

Dynamic responses of track structure and wave propagation in nearby ground vibration become significant when train operates on high speeds. A train-track-ground dynamic interaction analysis model based on the 2.5D finite element method is developed for the prediction of ground vibrations due to vertical track irregularities. The one-quarter car mode,1 is used to represent the train as lumped masses connected by springs. The embankment and the underlying ground are modeled by the 2.5D finite element approach to improve the computation efficiency. The Fourier transform is applied in the direction of train＇s movement to express the wave motion with a wave-number. The one-quarter car model is coupled into the global stiffness matrix describing the track-ground dynamic system with the displacement compatibility condition at the wheel-rail interface, including the irregularities on the track surface. Dynamic responses of the track and ground due to train＇s moving loads are obtained in the wave-number domain by solving the governing equation, using a conventional finite element procedure. The amplitude and wavelength are identified as two major parameters describing track irregularities. The irregularity amplitude has a direct impact on the vertical response for low-speed trains, both for short wavelength and long wavelength irregularities. Track irregularity with shorter wavelength can generate stronger track vibration both for low-speed and high-speed cases. For low-speed case, vibrations induced by track irregularities dominate far field responses. For high-speed case, the wavelength of track irregularities has very little effect on ground vibration at distances far from track center, and train＇s wheel axle weights becomes dominant.

关键词： High-speed railway 2.5D finite element method One-quarter car model Ground vibration Track irregularities