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Titanium-zirconium-phosphonate hybrid film on 6061 aluminum alloy

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Acta Metallurgica Sinica(English Letters) 2011年第1期24卷 18-22页

作者： Shuanghong wang Lei wang changsheng LIU Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern UniversityShenyang 110819 China

Three titanium-zirconium-phosphonate hybrid films were formed on AA6061 alu- minum alloy by immersing in fluorotitanic acid and fluorozirconic acid based solution containing different phosphonic acids for protective coatings of aluminium alloy. The corrosion resistance of three hybrid films as the substitute for chromate film were evaluated and compared. The neutral salt spray test was explored, the immersion test was conducted and electrochemical test was also executed. The hybrid films exhibited well-pleasing corrosion resistance and adhesion to epoxy resin paints. It was found out that the hybrid films could efficiently be a substitute for chromate based primer over aluminium alloy.

关键词： Aluminum alloy Titanium-zirconium-phosphonate Hybridfilm Corrosion resistance

Evaluation of the individual hydrogen bonding energies in N-methylacetamide chains

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Science China Chemistry 2010年第8期53卷 1754-1761页

作者： XiaoNan Jiang changsheng wang School of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China

The individual hydrogen bonding energies in N-methylacetamide chains were evaluated at the MP2/6-31+G** level including BSSE correction and at the B3LYP/6-311++G(3df,2pd) level including BSSE and van der Waals *** calculation results indicate that compared with MP2 results,B3LYP calculations without van der Waals correction underestimate the individual hydrogen bonding energies about 5.4 kJ m ol-1 for both the terminal and central hydrogen bonds,whereas B3LYP calculations with van der Waals correction produce almost the same individual hydrogen bonding energies as MP2 does for those terminal hydrogen bonds,but still underestimate the individual hydrogen bonding energies about 2.5 kJ mol-1 for the hydrogen bonds near the *** calculation results show that the individual hydrogen bonding energy becomes more negative (more attractive) as the chain becomes longer and that the hydrogen bonds close to the interior of the chain are stronger than those near the *** weakest individual hydrogen bonding energy is about-29.0 kJ m ol-1 found in the dimer,whereas with the growth of the N-methylacetamide chain the individual hydrogen bonding energy was estimated to be as large as-62.5 kJ mol-1 found in the N-methylacetamide decamer,showing that there is a significant hydrogen bond cooperative effect in N-methylacetamide *** natural bond orbital analysis indicates that a stronger hydrogen bond corresponds to a larger positive charge for the H atom and a larger negative charge for the O atom in the N-H···O=C bond,corresponds to a stronger second-order stabilization energy between the oxygen lone pair and the N-H antibonding orbital,and corresponds to more charge transfer between the hydrogen bonded donor and acceptor molecules.

关键词： N-methylacetamide chain the individual hydrogen bonding energy hydrogen bond cooperativity

Theoretical studies on the binding energy of β-sheet models

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Science China Chemistry 2009年第12期52卷 2243-2248页

作者： SUN ChangLiang wang changsheng School of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 116029China

In this paper,B3LYP and MP2 methods are used to investigate the binding energy of seventeen antiparallel and parallel β-sheet models. The results indicate that the binding energy obtained from B3LYP calculations is weaker than that obtained from MP2 calculations but the relative binding energy yielded by B3LYP is almost the same as that by MP2. For the antiparallel β-sheets in which two N―H···O═C hydrogen bonds can form either a large hydrogen-bonded ring or a small hydrogen-bonded ring,the binding energy increases obviously when one large ring unit is added,whereas it only changes slightly when one small ring unit is added because of the secondary electrostatic repulsive interaction existing in the small ring unit which is estimated to be about 20 kJ/mol. For the parallel β-sheet models,the binding energy increases almost exactly linearly with the increase of the chain length.

关键词： β-sheet models hydrogen bonds binding energy

Assumed stress quasi-conforming triangular element for couple stress theory

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Acta Mechanica Solida Sinica 2017年第4期30卷 335-344页

作者： changsheng wang Xiangkui Zhang Ping Hu School of Automotive Engineering State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of Technology

In this paper, a 3-node triangular element for couple stress theory is proposed based on the assumed stress quasi-conforming method. The formulation starts from polynomial approx- imation of stresses. Then the stress-function matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the string-net functions are introduced to calculate strain integration and the stress smooth technique is adopted to improve the stress accuracy. Numerical results show that the proposed new model can pass the Co- 1 patch test with excellent precision, does not exhibit extra zero energy modes and can cap- ture the scale effects of microstructure.

关键词： Quasi-conforming Couple stress theory Fundamental analytical solutions

Twenty years of rice genomics research: From sequencing and functional genomics to quantitative genomics

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Molecular Plant 2022年第4期15卷 593-619页

作者： changsheng wang Bin Han National Center for Gene Research State Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200233China

Since the completion of the rice genome sequencing project in 2005,we have entered the era of rice genomics,which is still in its *** genomics studies can be classified into three stages:structural genomics,functional genomics,and quantitative *** genomics refers primarily to genome sequencing for the construction of a complete map of rice genome *** is fundamental for rice genetics and molecular biology *** genomics aims to decode the functions of rice *** genomics is large-scale sequence-and statistics-based research to define the quantitative traits and genetic features of rice *** genomics has been a transformative influence on rice biological research and contributes significantly to rice breeding,making rice a good model plant for studying crop sciences.

关键词： rice Oryza sativa structural genomics functional genomics quantitative genomics

Shear behaviours and roughness degeneration based on a quantified rock joint surface description

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International Journal of Mining Science and Technology 2023年第10期33卷 1301-1316页

作者： Shubo Zhang Gang wang Yujing Jiang changsheng wang Feng Xu Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdao 266590China College of Civil Engineering Fujian University of TechnologyFuzhou 350118China Graduate School of Engineering Nagasaki UniversityNagasaki 852-8521Japan

The asperity wear of rock joints significantly affects their shear *** study discusses the wear damage of the asperities on the joint surface,highlighting the roughness degradation characteristics during the shear *** direct shear experiment of artificial specimens containing rock joints was conducted under different normal stresses based on three-dimensional scanning *** experimental results showed the contribution of joint wear to roughness degeneration,such as the height,zone,and volume of asperity *** wear coefficient of the rock joint was obtained based on the volume wear of asperities in the laboratory *** functional relationship between the friction coefficient and wear coefficient is subsequently *** quantitatively analyse the wear damage of a joint surface,a calculation method for determining the wear depth of the rock joint after shearing was proposed based on wear *** relationship between the ultimate dilation and wear depth was analysed.A coefficient m,which can describe the damage degree of the joint surface,and a prediction method of joint surface roughness after shearing are *** agreement between analytical predictions and measured values demonstrates the capability of the developed ***,the sensitivity factors on the wear depth are explored.

关键词： Rock joint Roughness Shear behaviour Wear Asperity

An improved apparent permeability model considering full pore pressure range,variable intrinsic permeability and slippage coefficient

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International Journal of Mining Science and Technology 2022年第6期32卷 1233-1244页

作者： Zhiyong Xiao changsheng wang Gang wang Yujing Jiang Junhong Yu Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdao 266590China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China College of Civil Engineering Fujian University of TechnologyFuzhou 350118China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

Although the slippage effect has been extensively studied,most of the previous studies focused on the impact of the slippage effect on apparent permeability within a low pore pressure range,resulting in the inability of matching the evolution of permeability in the remaining pressure *** this paper,a new apparent permeability model that reveals the evolution of permeability under the combined action of effective stress and slippage in the full pore pressure range was *** this model,both intrinsic permeability and slippage coefficient are stress *** experimental tests with pore pressure lower than 2 MPa and a test with pore pressure at about 10 MPa using cores from the same origin under constant confining stress and constant effective stress are *** comparing experimental data and another apparent permeability model,we proved the fidelity of our newly developed ***,the contribution factor of the slippage effect Rslip is used to determine the low pore pressure limit with significant slippage *** results show that both narrow initial pore size and high effective stress increase the critical pore ***,the evolutions of the slippage coefficient and the intrinsic permeability under different boundary conditions were analyzed.

关键词： Slippage effect Apparent permeability Contribution factor Critical pore pressure Intrinsic permeability

LINEAR AND GEOMETRICALLY NONLINEAR ANALYSIS WITH 4-NODE PLANE QUASI-CONFORMING ELEMENT WITH INTERNAL PARAMETERS

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Acta Mechanica Solida Sinica 2015年第6期28卷 668-681页

作者： changsheng wang Xiangkui Zhang Ping Hu Zhaohui Qi School of Automotive Engineering Dalian University of Technology State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Department of Engineering Mechanics Dalian University of Technology

A linear 4-node quadrilateral quasi-conforming plane element with internal parameters is proposed. The element preserves advantages of the quasi-conforming technique, including an explicit stiffness matrix, which can be applied to nonlinear problems. The weak patch test guarantees the convergence of the element. Then the linear element is extended to the geometri- cally nonlinear analysis in the framework of Total Lagrangian （TL） formulation. The numerical tests indicate that the present element is accurate and insensitive to mesh distortion.

关键词： quasi-conforming internal parameters plane element geometrically nonlinear

Rapid and accurate evaluation of the binding energies and the individual N H…O=C, N H…N, C H…O=C, and C H…N interaction energies for hydrogen-bonded peptide-base complexes

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Science China Chemistry 2013年第2期56卷 238-248页

作者： HUANG CuiYing LI Yang wang changsheng School of Chemistry and Chemical Engineering Liaoning Normal University

The binding energies of thirty-six hydrogen-bonded peptide-base complexes, including the peptide backbone-ase complexes and amino acid side chain-base complexes, are evaluated using the analytic potential energy function established in our lab recently and compared with those obtained from MP2, AMBER99, OPLSAA/L, and CHARMM27 calculations. The comparison indicates that the analytic potential energy function yields the binding energies for these complexes as reasonable as MP2 does, much better than the force fields do. The individual N H…O=C, N H…N, C H…O=C, and C H…N attractive interaction energies and C=O…O=C, N H…H N, C H…H N, and C H…H C repulsive interaction energies, which cannot be easily obtained from ab initio calculations, are calculated using the dipole-dipole interaction term of the analytic potential energy function. The individual N H…O=C, C H…O=C, C H…N attractive interactions are about 5.3±1.8, 1.2±0.4, and 0.8 kcal/mol, respectively, the individual N H … N could be as strong as about 8.1 kcal/mol or as weak as 1.0 kcal/mol, while the individual C=O…O=C, N H…H N, C H…H N, and C H…H C repulsive interactions are about 1.8±1.1, 1.7±0.6, 0.6±0.3, and 0.35±0.15 kcal/mol. These data are helpful for the rational design of new strategies for molecular recognition or supramolecular assemblies.

关键词： hydrogen bond peptide-base complexes total binding energy individual hydrogen bonding energy dipole-dipole interaction

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