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Amethod for sharing dynamic geometry information in studies on liquid-based detectors

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Nuclear Science and Techniques 2021年第2期32卷 101-111页

作者： Shu Zhang Jing-Shu Li Yang-Jie Su Yu-Mei Zhang Zi-Yuan Li Zheng-Yun You School of Physics Sun Yat-Sen UniversityGuangzhou 510275China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

Liquid-based detectors are widely used in particle and nuclear physics experiments.Because fixed method is used to construct the geometry in detector simulations such as Geant4,it is usually difficult to describe the non-uniformity of the liquid in a detector.We propose a method based on geometry description markup language and a tessellated detector description to share the detector geometry information between computational fluid dynamics simulation software and detector simulation software.This method makes it possible to study the impact of a liquid flow and non-uniformity on the key performance of a liquid-based detector,such as the event vertex reconstruction resolution.This will also be helpful in the detector design and performance optimization.

关键词： Liquid-based detector geometry Simulation Geant4 Computational fluid dynamics

Modeling yarn-level geometry from a single micro-image

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Frontiers of Information Technology & Electronic Engineering 2019年第9期20卷 1165-1174页

作者： Hong-yu WU Xiao-wu CHEN Chen-xu ZHANG Bin ZHOU Qin-ping ZHAO State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijing 100191China

Different types of cloth show distinctive appearances owing to their unique yarn-level geometrical details.Despite its importance in applications such as cloth rendering and simulation,capturing yarn-level geometry is nontrivial and requires special hardware,e.g.,computed tomography scanners,for conventional methods.In this paper,we propose a novel method that can produce the yarn-level geometry of real cloth using a single micro-image,captured by a consumer digital camera with a macro lens.Given a single input image,our method estimates the large-scale yarn geometry by image shading,and the fine-scale fiber details can be recovered via the proposed fiber tracing and generation algorithms.Experimental results indicate that our method can capture the detailed yarn-level geometry of a wide range of cloth and reproduce plausible cloth appearances.

关键词： Single micro-images Yarn geometry Cloth appearance

On the Second Harmonic Generation through Bell-Plesset Effects in Cylindrical geometry

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Chinese Physics Letters 2014年第4期31卷 85-88页

作者： GUO Hong-Yu YU Xiao-Jin WANG Li-Feng YE Wen-Hua WU Jun-Feng LI Ying-Jun State Key Laboratory for Geomeehanics and Deep Underground Engineering China University of Mining and Technology Beijing 100083 Institute of Applied Physics and Computational Mathematics Beijing 100094 HEDPS Center for Applied Physics and Technology Peking University Beijing 100871 Department of Physics Zhejiang University Hangzhou 310027

Generation of the second harmonic initiated by Bell-Plesset effects in a cylindrical geometry is studied analytically. For an initial single-mode velocity perturSation, the second-order mode-coupling formula is obtained by expanding the perturbation displacement and velocity potential up to the second-order accuracy. It is found that the initially symmetric interface evolves into a significant bubble-spike asymmetric pattern. The second-order solutions clearly show that the amplitude of the spike grows faster than that of the buSble. The temporal evolutions of the amplitudes of the 5ubSie and spike are dependent on the interface velocity Vo. The larger interface velocity leads to the smaller amplitude of the perturbation at an arbitrary interface position in a cylindrically convergent geometry.

关键词： geometry Second Harmonic second

A geometry Model for Tortuosity of Streamtubes in Porous Media with Spherical Particles

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Chinese Physics Letters 2005年第6期22卷 1464-1467页

作者：吴美娟郁伯铭张斌黄明涛 DepartmentofPhysicsandtheStateKeyLaboratoryofPlasticFormingandDie&MoldTechnology HuazhongUniversityofScienceandTechnologyWuhan430074

A geometry model for tortuosity of tortuous streamtubes in porous media with spherical particles is proposed based on the assumption that some particles in a porous medium are unrestrictedly overlapped and hence of different configurations. The proposed model is a function of porosity with no empirical constant imposed on it. The model predictions are found to be in good agreement with the available experimental data.

关键词： LG BC geometry

Microfluidics-based assay on the effects of microenvironmental geometry and aqueous flow on bacterial adhesion behaviors

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Journal of Pharmaceutical Analysis 2011年第3期1卷 175-183页

作者： Yang Liu Jian-Chun Wang Li Ren Qin Tu Wen-Ming Liu Xue-Qin Wang Rui Liu Yan-Rong Zhang Jin-Yi Wang College of Science Northwest A&F University Yangling Shaanxi 712100 China College of Veterinary Medicine Northwest A&F University Yangling Shaanxi 712100 China Shaanxi Key Laboratory of Molecular Biology .for Agriculture Northwest A&F University Yangling

Abstract A new microfluidic system with four different microchambers （a circle and three equilateral concave polygons） was designed and fabricated using poly（dimethylsiloxane）（PDMS） and the soft lithography method. Using this microfluidic device at six flow rates （5, 10, 20, 30, 40, and 50 μL/h）, the effects of microenvironmental geometry and aqueous flow on bacterial adhesion behaviors were investigated. Escherichia coli HB101 pGLO, which could produce a green fluorescent protein induced by L-arabinose, was utilized as the model bacteria. The results demonstrated that bacterial adhesion was significantly related to culture time, microenvironment geometry, and aqueous flow rates. Adhered bacterial density increased with the culture time. Initially, the adhesion occurred at the microchamber sides, and then the entire chamber was gradually covered with increased culture time. Adhesion densities in the side zones were larger than those in the center zones because of the lower shearing force in the side zone. Also, the adhesion densities in the complex chambers were larger than those in the simple chambers. At low flow rates, the orientation of adhered bacteria was random and disorderly. At high flow rates, bacterial orientation became close to the streamline and oriented toward the flow direction; All these results implied that bacterial adhesion tended to occur in complicated aqueous flow areas.The present study provided an on-chip flow system for physiological behavior of biological cells, as well as provided a strategic cue for the prevention of bacterial infection and biofilm formation.

关键词： Microfluidic device Escherichia coli Adhesion behaviors geometry Aqueous flow

MULTIPLE-SCATTERING DETERMINATION TO THE LOCAL ADSORPTION geometry OF SO_2/Pd(111)

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 81-86页

作者： S. Cao J.C. Tang P. Zhu L. Wang S.L Shen Dept. of Phys. Zhejiang Univ. Hangzhou 310027 China

We have calculated the sulphur 1s near edge X-ray absorption fine structure (NEXAFS) spectra of SO2 adsorbed on Pd (111) in terms of the Multiple-Scattering Cluster (MSC) method. The origin of the resonances in the NEXAFS spectra has been revealed. By the MSC calculation and a (DV)-Xα study we have for the first time identified two weak features existing in S K-edge NEXAFS of SO2/Pd(111) system, which are attributed to the interaction between the adsorbate and the substrate. Moreover, MSC calculation together with the reliability factor (R-factor) analysis are employed to determine the local adsorption structures. These results are broadly in agreement with those of Fourier-transform analysis of the surface extended X-ray absorption fine structure (SEXAFS).

关键词： Absorption geometry Palladium Scattering Sulfur dioxide X ray spectroscopy

Alternating Terpolymers Based on Tunable Bi-donors with Manipulating Energy Levels and Molecular geometry

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Chemical Research in Chinese Universities 2017年第2期33卷 305-311页

作者： CHEN Zhenzhu YANG Jia WU Feiyan CHEN Lie CHEN Yiwang College of Chemistry Institute of Polymers Nanchang University Nanchang 330031 P. R. China Jiangxi Provincial Key Laboratory of New Energy Chemistry Nanchang University Nanchang 330031 P. R. China

Three novel regular acceptor-donorl-acceptor-donor2（A-D1-A-D2） terpolymers were prepared via em-bedding a second donor（D2） unit into the traditional D-A backbone to manipulate the energy levels and moleculargeometry with no complex synthesis or solubility loss. In these A-D1-A-D2 terpolymers, benzodithiophene（BDT, D1）and diketopyrrolopyrrole（DPP, A） were selected as the basic skeleton, and the dithienopyrrole（DTPy）, carbazole（CZ）and fluorine（FL） units with different electron donating ability were chosen as the second donor trait（D2）. The HOMOenergy levels can be effectively modulated by only varying D2 unit because of the push-pull interaction between do-nor and acceptor units. Versus the D-A bipolymer PDPP-BDT, incorporation of the D2 unit into the copolymers candistinctly lower the highest occupied molecular orbital（HOMO） levels to -5.47 eV for PDDPP-BDT-DTPy, -5.38 eVfor PDDPP-BDT-CZ and -5.23 eV for PDDPP-BDT-FL, which shows the strong dependence on electron-donatingability. Density functional theory（DFT） simulation and X-ray diffraction（XRD） measurements also reveal the effectof the D2 units on the molecular geometry of the terpolymers and their molecular packing. Notably, aPDDPP-BDT-DTPy combined with a thiophene ring and forked tail pendant away from the backbone had less back-bone torsion and more compact packing than the other two counterparts. These results demonstrate that embedding asecond donor（D2） unit into the backbone to construct an A-D1-A-D2 structure can be an effective and direct strategyto manipulate the energy levels and molecular geometry and develop organic semiconducting materials.

关键词： Terpolymer Electron-donating Energy level Molecular geometry

Influence of fault geometry and fault interaction on strain partitioning within western Sichuan and its adjacent region

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Science China Earth Sciences 2010年第7期53卷 1056-1070页

作者： WANG Hui LIU Jie SHEN XuHui LIU Mian LI QingSong SHI YaoLin ZHANG GuoMin Institute of Earthquake Science China Earthquake AdministrationBeijing 100036China Department of Geological Sciences University of MissouriColumbiaMO 65211USA China Earthquake Network Center China Earthquake AdministrationBeijing 100045China Lunar and Planetary Institute HoustonTX 77058USA Laboratory of Computational Geodynamics Graduate University of Chinese Academy of SciencesBeijing 100049China

There are several major active fault zones in the western Sichuan and its vicinity. Slip rates and seismicity vary on different fault zones. For example, slip rates on the Xianshuihe fault zone are higher than 10 mm/a. Its seismicity is also intense. Slip rates on the Longmenshan fault zone are low. However, Wenchuan Ms8.0 earthquake occurred on this fault zone in 2008. Here we study the impact of fault geometry on strain partitioning in the western Sichuan region using a three-dimensional viscoe- lastoplastic model. We conclude that the slip partitioning on the Xianshuihe-Xiaojiang fault presents as segmented, and it is related to fault geometry and fault structure. Slip rate is high on fault segment with simple geometry and structure, and vice versa. Strain rate outside the fault is localized around the fault segment with complex geometry and fault structure. Strain partitioning on the central section of the Xianshuihe-Xiaojiang fault zone is influenced by the interaction between the Anninghe-Zemuhe fault and the Daliangshan fault zone. Striking of the Longmenshan fault zone is nearly orthogonal to the direction of eastward extrusion in the Tibetan Plateau. It leads to low slip rate on the fault zone.

关键词： Xianshuihe-Xiaojiang fault zone Longmenshan fault zone fault geometry strain partitioning 3D viscoelastoplastic model

Ab initio Study on the Molecular geometry, Electronic Structure and Thermodynamic Properties of Benzotrifuroxan(BTF)

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Chinese Journal of Structural Chemistry 1999年第2期18卷 49-55页

作者： Gong, XD Xiao, HM Dong, HS Nanjing Univ Sci & Technol Dept Chem Nanjing 210094 Peoples R China China Acad Engn Phys Inst Chem Mat Mianyang 610003 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｎｚｏｔｒｉｆｕｒｏｘａｎ（ＢＴＦ）ｉｓａｐｏｗｅｒｆｕｌ，ｈｙｄｒｏｇｅｎｆｒｅａｎｄｒｅｌａｔｉｖｅｌｙｓｅｎｓｉｔｉｖｅｅｘｐｌｏｓｉｖｅ．Ｓｉｎｃｅｔｈｉｓｃｏｍｐｏｕｎｄｗ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｎｚｏｔｒｉｆｕｒｏｘａｎ（ＢＴＦ）ｉｓａｐｏｗｅｒｆｕｌ，ｈｙｄｒｏｇｅｎｆｒｅａｎｄｒｅｌａｔｉｖｅｌｙｓｅｎｓｉｔｉｖｅｅｘｐｌｏｓｉｖｅ．Ｓｉｎｃｅｔｈｉｓｃｏｍｐｏｕｎｄｗａｓｆｉｒｓｔｐｒｅｐａｒｅｄ，ｉ...

关键词： benzotrifuroxan(BTF) ab initio MO method molecular geometry electronic structure IR frequency thermodynamic property