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Synthesis and Structure of Manganese Coordinated Polymer with Regular X-shaped Cavity

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Chemical Research in Chinese Universities 2004年第3期20卷 338-340页

作者： MADong-sheng GaoShan HUOLi-hua GAOJing-sheng SUNZhi-zhong CollegeofChemistryandChemicalEngineering HeilongjiangUniversityHarbin150080P.R.China

A coordination polymer \\-\%n\%(H\-2IDA=\%N\%\|iminodiacetic acid) was synthesized and characterized by single crystal X\|ray diffraction. The crystal belongs to the tetragonal system,the space group is \%P\|42\-1C\% with the crystal cell parameters \%a\%=0\^81120(8) nm,\%b\%=0\^81120(8) nm,\%c\%=0\^96196(4) nm,\%V\%=0\^6330(1) nm\+3,\%M\%\-r=355\^17,\%R\%=0\^0224,\%wR\%=0\^061. The four carboxylic oxygen atoms of the different \%N\%\|iminodiacetic acid ligands and two water molecules coordinate to the manganese atom. The manganese atom is in an approximates octahedral coordination sphere. Each carboxylic acid ligand bridges two manganese atoms,forming two zig\|zag supramolecular chains. The twisted chains construct a two\|dimension layer structure with regularly arranged X\|shaped window cavity. The three\|dimension supramolecular network is formed by coordination bonds and hydrogen bonds.

关键词： Coordination polymer Synthesis Crystal structure

Lower Bounds for Moments of Quadratic Twisted Self-dual GL(3)Central L-values

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2139-2148页

作者： sheng Hao hua Bing Rong huaNG Data Science Institute and School of Mathematics Shandong UniversityJi’nan 250100P.R.China

In this paper,we prove the conjectured order lower bound for the k-th moment of central values of quadratic twisted self-dual GL(3)L-functions for all k≥1,based on our recent work on the twisted first moment of centr... 详细信息

关键词： GL(3)cusp form lower bound quadratic twist central value L-function

A COUPLING MODEL OF WATER FLOWS AND GAS FLOWS IN EXHAUSTED GAS BUBBLE ON MISSILE LAUNCHED UNDERWATER

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Journal of Hydrodynamics 2007年第4期19卷 403-411页

作者： CHENG Yong-sheng LIU hua Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200030 China

The gas and water flows during an underwater missile launch are numerically studied. For the gas flow, the explicit difference scheme of Non-oscillation and Non-free-parameter Dissipation (NND) is utilized to solve the Euler equations for compressible fluids in the body-fitted coordinates. For the water flow, the Hess-Smith method is employed to solve the Laplace equation for the velocity potential of irrotational water flows based on the potential theory and the boundary element method. The hybrid Eulerian-Lagrangian formulation for the free boundary conditions is used to compute the changes of the free surface of the exhausted gas bubble in time stepping. On the free surface of the exhausted gas bubble, the matched conditions of both the normal velocities and pressures are satisfied. From the numerical simulation, it is found that the exhausted gas bubble grows more rapidly in the axial direction than in the radial direction and the bubble will shrink at its "neck" finally. Numerical results of the movement of the shock wave and the distribution of the Mach number and the gas pressure within the bubble were presented, which reveals that at some time, the gas flow in the Laval nozzle is subsonic and the gas pressure in the nozzle is very high. Influences of various initial missile velocities and chamber total pressures and water depths on both the time interval when the gas flow in the nozzle is subsonic and the peak of the gas pressure at the nozzle end were discussed. It was suggested that a reasonable adjustment of the chamber total pressure can improve the performance of the engine during the underwater launch of missiles.

关键词： exhausted gas bubble Laval nozzle missile launched underwater shock wave gas jet

THEORETICALLY AND NUMERICALLY ASSESSING THE VALIDITY OF EULERIAN TRUNCATION IN STOCHASTIC GROUNDWATER MODELING

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Journal of Hydrodynamics 2002年第3期14卷 13-20页

作者： Liao, hua-sheng Li, Shu-Guang Hydraulics Lab.of High Speed Flows Sichuan Univ. Chengdu 610065 China Dept. of Civil and Environ. Eng. Michigan State Univ. East Lansing MI 48824 United States

A theoretical and numerical assessment of the validity of Eulerian truncation in stochastic modeling is presented. Specifically, we analyze and compare theoretically various existing Eulerian-based first-order techniques with and without invoking Eulerian truncation and quantify the terms truncated and retained in the stochastic perturbation equations using high resolution Monte Carlo simulations. We also analyze and compare numerically various existing Eulerian-based first-order techniques and Monte Carlo simulation. The obtained results have demonstrated theoretically and numerically that existing Eulerian-based stochastic perturbation techniques are equivalent. The terms truncated are indeed one order higher than those retained. Therefore, we conclude that Eulerian truncation is mathematically consistent and asymptotic.

关键词： Computer simulation Monte Carlo methods Perturbation techniques Random processes Stochastic programming

Visualization of flow behavior in ore-segregated packed beds with fine interlayers

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 900-909页

作者： Lei-ming Wang sheng-hua Yin Ai-xiang Wu Key Laboratory of Ministry of Education for High-Efficient Mining and Safety of Metal University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Materials Engineering University of British Columbia309-6350 Stores RoadVancouver V6T 1Z4BCCanada

Ore particles,especially fine interlayers,commonly segregate in heap stacking,leading to undesirable flow paths and changeable flow velocity fields of packed *** tomography(CT),COMSOL Multiphysics,and MATLAB were utilized to quantify pore structures and visualize flow behavior inside packed beds with segregated fine *** formation of fine interlayers was accompanied with the segregation of particles in packed *** particles reached the upper position of the packed beds during *** revealed that the average porosity of fine interlayers(24.21%)was significantly lower than that of the heap packed by coarse ores(37.42%),which directly affected the formation of flow ***,the potential flow paths in the internal regions of fine interlayers were *** flowed and bypassed the fine interlayers and along the sides of the packed *** velocity also indicated that the flow paths easily gathered in the pore throat where flow velocity(1.8×10^-5 m/s)suddenly *** stagnant regions with a flow velocity lower than 0.2×10^-5 m/s appeared in flow paths with a large diameter.

关键词： fine interlayer flow behavior computed tomography segregation preferential flow

Calibration of line structured light vision system based on camera’s projective center

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光学精密工程 2005年第5期13卷 584-591页

作者： ZHU Ji-gui LI Yan-jun YE sheng-hua State Key Laboratory of Precision Measuring Technology and Instrument Tianjin Universality Tianjin 300072China

Based on the characteristics of line structured light sensor, a speedy method for the calibration was established. With the coplanar reference target, the spacial pose between camera and optical plane can be calibrated by using of the camera’s projective center and the light’s information in the camera’s image surface. Without striction to the movement of the coplanar reference target and assistant adjustment equipment, this calibration method can be implemented. This method has been used and decreased the cost of calibration equipment, simplified the calibration procedure, improved calibration efficiency. Using experiment, the sensor can attain relative accuracy about 0.5%, which indicates the rationality and effectivity of this method.

关键词：投影中心线性结构光传感器标度可视性系统

A HYBRID MODEL FOR SIMULATING VELOCITY FIELD OF A RIVER WITH COMPLEX GEOMETRY PLUNGED BY MULTIPLE JETS

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Journal of Hydrodynamics 2006年第6期18卷 752-759页

作者： LI Lian-xia LIAO hua-sheng LI Tian-xiang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A hybrid model that combines both physical and numerical models was employed to simulate the velocity field in a river area in complex geometry with multiple plunging jets. The simulation was based on experiments concerning energy dissipation and scour prevention at the Xiluodu Hydropower Station on the Yangtze River. The calculated results indicate that the complex geometry of the river area has a significant influence on the velocity field, especially on the circulation flow pattern at upstream and downstream of the plunging area and on the asymmetric characteristics of the spiral flow near both banks. The scour characteristics of the downstream river bed caused by the multiple jets were also predicted and analyzed according to the characteristics of the calculated velocity field. The good agreement between the simulated and experimental results indicates that the hybrid model can be used to effectively solve complicated 3-D problems with complex geometric and inlet conditions. Such problems may not easily be solved by using either a physical or a numerical model alone, and therefore the method presented in this article is considered to be a practical and effective way of dealing with this kind of problems.

关键词： hybrid models turbulence model scour multiple jets

Dimensionality Reducing from Three-dimensional RbLu5Te8 to Two-dimensional CsMnGdTe3:Syntheses,Crystal and Electronic Structures

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Chinese Journal of Structural Chemistry 2020年第10期39卷 1770-1780,1741页

作者： ZHANG Jian-Han ZHOU sheng-hua LIN hua School of Resources&Chemical Engineering Sanming UniversitySanming 365004China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Two new rare-earth metal chalcogenides,namely RbLu5Te8 and CsMnGdTe3,have been successfully synthesized under high-temperature solid-state reaction conditions and structurally characterized by single-crystal X-ray diffraction ***5Te8 belongs to the monoclinic space group C2/m(no.12)with two formula units in a unit cell:a=22.075(5),b=4.2987(8),c=10.588(2)A,β=103.89(2)°,V=975.4(4)A3,whereas CsMnGdTe3 crystallizes in the orthorhombic space group Cmcm(no.63)with four formula units in a unit cell:a=4.4872(8),b=16.769(3),c=11.807(2)A and V=888.4(3)*** the structure of RbLu5Te8,face-,edgeand vertex-sharing[LuTe6]octahedra are interconnected to produce a three-dimensional(3D)framework with Rb^+lying in the *** crystal structure of CsMnGdTe3 consists of two-dimensional(2D)[MnGdTe3]^–layers of edge-and vertex-sharing[GdTe6]octahedra with Mn atoms filling the tetrahedral interstices,which stack along the *** Cs atoms are located between the[MnGdTe3]^–layers and surrounded by eight Te atoms to form a[CsTe8]bicapped trigonal ***,theoretical studies have aided the understanding of their electronic structures.

关键词： rare-earth telluride structural dimension high-temperature solid-state reaction crystal structure electronic structures

MicroRNAs as potential biomarkers for gastric cancer

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World Journal of Gastroenterology 2014年第34期20卷 12007-12017页

作者： Han-Shao Liu hua-sheng Xiao National Engineering Research Center for Biochip at Shanghai Shanghai-MOST Key Laboratory for Disease and Health Genomics Chinese National Human Genome Center at Shanghai Advanced Institute of Translational Medicine Tongji University

Gastric cancer is the fourth most common cancer in the world and the second leading cause of cancer-related death. More than 80% of diagnoses occur at the middle to late stage of the disease, highlighting an urgent need for novel biomarkers detectable at earlier stages. Recently, aberrantly expressed microRNAs (miRNAs) have received a great deal of attention as potential sensitive and accurate biomarkers for cancer diagnosis and prognosis. This review summarizes the current knowledge about potential miRNA biomarkers for gastric cancer that have been reported in the publicly available literature between 2008 and 2013. Available evidence indicates that aberrantly expressed miRNAs in gastric cancer correlate with tumorigenesis, tumor proliferation, distant metastasis and invasion. Furthermore, tissue and cancer types can be classified using miRNA expression profiles and next-generation sequencing. As miRNAs in plasma/serum are well protected from RNases, they remain stable under harsh conditions. Thus, potential functions of these circulating miRNAs can be deduced and may implicate their diagnostic value in cancer detection. Circulating miRNAs, as well as tissue miRNAs, may allow for the detection of gastric cancer at an early stage, prediction of prognosis, and monitoring of recurrence and/or lymph node metastasis. Taken together, the data suggest that the participation of miRNAs in biomarker development will enhance the sensitivity and specificity of diagnostic and prognostic tests for gastric cancer. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.

关键词： MicroRNAs Gastric cancer Biomarker Clinical application