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Hypersonic shock wave and turbulent boundary layer interaction in a sharp cone/flare model

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Chinese Journal of Aeronautics 2023年第3期36卷 80-95页

作者： Fulin TONG Junyi DUAN Jiang LAI dong sun Xianxu YUAN State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China LHD Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

A direct numerical simulation of hypersonic Shock wave and Turbulent Boundary Layer Interaction(STBLI)at Mach 6.0 on a sharp ***-angle circular cone/flare configuration at zero angle of attack is *** flare angle is *** the momentum thickness Reynolds number based on the incoming turbulent boundary layer on the sharp circular cone is Re θ=*** is found that the mean flow is separated and the separation bubble occurring near the corner exhibits *** Reynolds analogy factor changes dramatically across the interaction,and varies between 1.06 and 1.27 in the downstream region,while the QP85 scaling factor has a nearly constant value of 0.5 across the *** evolution of the reattached boundary layer is characterized in terms of the mean profiles,the Reynolds stress components,the anisotropy tensor and the turbulence kinetic *** is argued that the recovery is incomplete and the near-wall asymptotic behavior does not occur for the hypersonic *** addition,mean skin friction decomposition in an axisymmetric turbulent boundary layer is carried out for the first *** of the interaction,the contributions of transverse curvature and body divergence are negligible,whereas the positive contribution associated with the turbulence kinetic energy production and the negative spatial-growth contribution are *** on scale decomposition,the positive contribution is further divided into terms with different spanwise length *** negative contribution is analyzed by comparing the convective term,the streamwise-heterogeneity term and the pressure gradient term.

关键词： Shock wave Hypersonic turbulent boundary layer Heat transfer Skin friction decomposition Direct numerical simulation

Advanced tools and methods for single-cell surgery

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Microsystems & Nanoengineering 2022年第2期8卷 1-21页

作者： Adnan Shakoor Wendi Gao Libo Zhao Zhuangde Jiang dong sun Department of Biomedical Engineering City University of Hong KongHong KongChina State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesThe School of Mechanical EngineeringXi'an Jiaotong UniversityXi'anChina

Highly precise micromanipulation tools that can manipulate and interrogate cell organelles and components must be developed to support the rapid development of new cell-based medical therapies,thereby facilitating in-depth understanding of cell dynamics,cell component functions,and disease *** paper presents a literature review on micro/nanomanipulation tools and their control methods for single-cell *** methods specifically based on laser,microneedle,and untethered micro/nanotools are presented in *** limitations of these techniques are also *** biological significance and clinical applications of single-cell surgery are also addressed in this paper.

关键词： manipulation surgery needle

Properties and photodetector applications of two-dimensional black arsenic phosphorus and black phosphorus

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Science China(Information Sciences) 2021年第4期64卷 120-133页

作者： Ruyue HAN Shun FENG dong-Ming sun Hui-Ming CHENG Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China School of Physical Science and Technology ShanghaiTech University Shenzhen Geim Graphene Center Shenzhen International Graduate School Tsinghua University

Two-dimensional(2D) black arsenic phosphorus(b-AsP), as an alloy of black phosphorus(bP) with arsenic, has attracted great attention because of its outstanding electronic and optical properties,including high carrier mobility, tunable bandgap and in-plane anisotropy. B-AsP has a smaller bandgap(0.15–0.3 eV) than the b-P bandgap(0.3–2.0 eV), and thus can be used for mid-infrared *** addition, both of them can form various van der Waals(vdW) heterojunctions with other 2D materials to realize novel functional optoelectronic devices. Here, we compare the basic characteristics of b-AsP and b-P, including crystal structure, optical properties, band structure, electrical properties and stability, and we summarize the update progress of b-AsP in photo detection, including representatives of phototransistor and photodiode devices. In the last part, the future research directions are discussed.

关键词： black arsenic phosphorus crystal structure optical property electrical property photodetector

Further Study on Errors in Metric Evaluation by Linear Upwind Schemes with Flux Splitting in Stationary Grids

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Communications in Computational Physics 2017年第6期22卷 64-94页

作者： Qin Li dong sun Pengxin Liu State Key Laboratory of Aerodynamics MianyangSichuan621000P.R.China National Laboratory of Computational Fluid Dynamics Beijing University of Aeronautics and AstronauticsBeijing 100191P.R.China

The importance of eliminating errors in grid-metric evaluation for highorder difference schemes has been widely recognized in recent years,and it is known from the proof by Vinokur and Yee(NASA TM 209598,2000)that when conservative derivations of grid metric are used by Thomas,Lombard and Neier(AIAA J.,1978,17(10)and *** and rocket,1990,27(2)),errors caused by metric evaluation could be eliminated by linear schemes when flux splitting is not *** to the above achievement,central schemes without the use of flux splitting could fulfill the requirement of error *** will arise for upwind schemes to attain the objective when the splitting is *** this study,further investigations are made on three aspects:Firstly,an idea of central scheme decomposition is introduced,and the procedure to derive the central scheme is proposed to evaluate grid metrics ***,the analysis has been made on the requirement of flux splitting to acquire free-stream preservation,and a Lax-Friedrichs-type splitting scheme is proposed as an *** about current study with that by Nonomura et al.(Computers and Fluids,2015,107)have been ***,for halfnode-or mixed-type schemes,interpolations should be used to derive variables at half *** requirement to achieve metric identity on this situation is analyzed and an idea of directionally consistent interpolation is proposed,which is manifested to be indispensable to avoid violations of metric identity and to eliminate metric-caused errors *** numerical problems are tested,i.e.,the free-stream and vortex preservation onwavy,largely randomized and triangular-like *** results validate aforementioned theoretical outcomes.

关键词： Upwind scheme flux splitting metric identity free-streampreservation

WENO Interpolation-Based and Upwind-Biased Free-Stream Preserving Nonlinear Schemes

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Advances in Applied Mathematics and Mechanics 2021年第6期13卷 1441-1484页

作者： Qin Li dong sun Fengyuan Xu State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyangSichuan 621000China Key Laboratory of Aerodynamics Noise Control China Aerodynamics Research and Development CenterMianyangSichuan 621000China School of Aerospace Engineering Xiamen UniversityXiamenFujian 361102China

For flow simulations with complex geometries and structured grids,it is preferred for high-order difference schemes to achieve high *** order to achieve this goal,the satisfaction of free-stream preservation is necessary to reduce the numerical error in the numerical evaluation of grid *** the linear upwind schemes with flux splitting the free-stream preserving property has been achieved in the early study[*** et al.,***.,22(2017),pp.64–94].In the current paper,new series of nonlinear upwind-biased schemes through WENO interpolation will be *** the new nonlinear schemes,the shock-capturing capability on distorted grids is achieved,which is unavailable for the aforementioned linear upwind *** the inclusion of fluxes on the midpoints,the nonlinearity in the scheme is obtained through WENO interpolations,and the upwind-biased construction is acquired by choosing relevant grid *** third-and fifth-order nonlinear schemes are developed and *** are made among proposed schemes,alternative formulations of WENO and hybrid WCNS,in which a general formulation of center scheme with midpoint and nodes employed is obtained as a *** the numerical tests,the proposed schemes can achieve the designed orders of accuracy and free-stream preservation *** 1-D Sod and Shu-Osher problems,the results are consistent with the theoretical *** 2-D cases,the vortex preservation,supersonic inviscid flow around cylinder at M¥=4,Riemann problem,and shock-vortex interaction problems have been *** specifically,two types of grids are employed,i.e.,the uniform/smooth grids and the randomized/locally-randomized *** schemes can get satisfactory results in uniform/smooth *** the randomized grids,most schemes have accomplished computations with reasonable accuracy,except the failure of one third-order scheme in Riemann problem and shock-vortex ***,the proposed nonlinear

关键词： High-order difference scheme upwind-biased scheme WENO interpolation freestream preservation hybrid WCNS

Novel dye-sensitized solar cell architecture using TiO2-coated Ag nanowires array as photoanode

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Rare Metals 2019年第4期38卷 316-320页

作者： Ming Wang Sam Zhang Zhao-Fu Du Li-dong sun dong-Liang Zhao Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639789 Singapore

With the aim of reducing series resistance and increasing dye loading,novel dye-sensitized solar cell architecture was designed with TiO2 nanoparticle-coated Ag nanowires array as the *** nanowire array was prepared by anodic aluminum oxide (AAO) templateassisted electrochemical deposition ***,Ag nanowires were coated by TiO2 nanoparticles in hydrothermal *** structures of the photoanode were characterized by field emission scanning electron microscopy (FESEM).Ag nanowires are covered by a layer of very fine nanoparticles with a diameter of less than 5 nm.X-ray diffraction (XRD) and selected-area electron diffraction (SAED) show that Ag nanowires have a strong preferred orientation in (220) direction and the TiO2 coating layer is a polycrystalline *** this photoanode,3.2 % conversion efficiency is achieved for the cell sensitized with N3 dye.

关键词： Dye-sensitized solar cell Nano wires array Photoanode Anodic aluminum oxide

N ＝ 4 Superconformal Quantum Mechanics in One Dimension and Its Algebraic Structure

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Communications in Theoretical Physics 2002年第7期38卷 11-14页

作者： RUAN dong GUO Hao sun Hong-Zhou Department of Physics Tsinghua University Beijing 100084 China The Key Laboratory of Quantum Information and Measurements of Ministry of Education Tsinghua University Beijing 100084 China Center of Theoretical Nuclear Physics National Laboratory of Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China Institute of Theoretical Physics Academia Sinica Beijing 100080 China

N = 4 superconformal quantum mechanics of nonrelativistic particles in the typical 1/x2-potentials, which holds not only supersymmetry but also dynamical conformal symmetry, is studied. The corresponding superconformal quantum mechanical algebra, which contains supersymmetric quantum mechanical algebra with four supercharges and conformal algebra as subalgebras, and its two canonical group chains are established.

关键词： supersymmetry, conformal symmetry, superconformal algebra

Novel Stereoselective Carbonyl Reductase from Kluyveromyces marxianus for Chiral Alcohols Synthesis

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Chemical Research in Chinese Universities 2013年第6期29卷 1140-1148页

作者： LI Hai-dong sun Zhi-hao NI Ye Key Laboratory of Industrial Biotechnology Ministry of Education School of BiotechnologyJiangnan University Wuxi 214122 P.R.China

A novel nicotinamide adenine dinucleotide phosphate（NADPH）-dependent carbonyl reductase from Kluyverornyces marxianus（KmCR） was identified, which can convert various prochiral ketone esters and ketone substrates to their corresponding chiral alcohols. KmCR was over-expressed in E. coli BL21（DE3）, purified to homogeneity, and characterized. The purified enzyme exhibits the highest activity at 40℃ and pH=6.0. Based on the gel filtration and sodium dodecyl sulfate-polyacrylamide gel eiectrophoresis（SDS-PAGE） analysis, the monomeric protein was determined to have a molecular weight of approximate 39000. Vmax and Km of KmCR are 4.28 μ***^-1·mg^-1 and 0.41 mmol/L for ketone ester substrate ethyl 2-oxo-4-phenylbutyrate（OPBE）, 3.09μ***^-1·mg^-1 and 1.21 mmol/L for cofactor NADPH, respectively. Cofactor recycle was achieved by co-expression of KmCR and glucose dehydrogenase（GDH） in E. coli. Recombinant E. coli harboring KmCR and GDH showed moderate asymmetric reduction activity towards various α- and β-ketoesters, diaryl ketone substrates. In an aqueous/butyl acetate biphasic system, the whole-cell biocatalyst was used to prepare ethyl （R）-2-hydroxy-4- phenylbutanoate[（R）-HPBE] in an e.e. of 99.5% with a space-time yield of 433.6 g.L-1.d-1 and a yield of 80.3% at 270 g/L OPBE.

关键词： Carbonyl reductase Asymmetric reduction Chiral alcohol co-Expression Kluyveromyces marxianus

Nonexistence and Longtime Behaviors of Solutions to a Class of Nonlinear Degenerate Parabolic Equations Not in Divergence Form

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 327-332页

作者： Yu-dong sun Yi-min SHI MIN WU School of Science Guizhou Minzu University Department of Applied Mathematics Northwestern Polytechnical University

In this paper, we study the nonexistence and longtime behavior of weak solution for the degenerate parabolic equation σtun=umdiv（｜▽um｜p-2▽um）＋γ｜▽um｜p＋βun with zero boundary condition. Blow-up time is der... 详细信息

关键词： nonexistence nonlinear degenerate parabolic equations weak solution blow-up