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Sliding Dynamics of Slide-Ring Polymers Based on the Bead-Spring Model

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Chinese Journal of Polymer Science 2023年第9期41卷 1410-1424,I0007页

作者： Zhong-qiang Xiong wei Yu Advanced Rheology Institute Department of Polymer Science and EngineeringState Key Laboratory for Metal Matrix Composite MaterialsShanghai Jiao Tong UniversityShanghai200240China

Understanding the sliding dynamics is critical for developing rotaxane-based mechanically interlocked *** this work,we studied the sliding behavior of a sliding ring and its influence on the dynamics of attached polymer chains based on the heterogeneous beadspring *** sliding constraint was treated as direction-related confinement with the heterogeneous friction coefficient and constraint *** relaxation spectrum,the diffusion dynamics,and the sliding dynamics under/after drag were studied for typical sliding chain topologies,namely,the sliding dangling chain,the constraint sliding chain,and the sliding *** with the non-sliding chains(such as the free chain,the dangling chain,and the network strand),the slide of one or two chain ends induces an additional slow process in the transition from the Rouse-type behavior to the long-time terminal *** effect of the sliding-related process on the diffusion of specific chain segments relies on the chain *** slow sliding relaxation process is also observed in the sliding process during and after chain deformation,whose characteristic time is at least three times the terminal relaxation time of the free chain with the same length,and will increase with the friction coefficient(i.e.,the interaction)between the ring and the polymer *** results of this work will benefit the understanding of the sliding dynamics in experiments.

关键词： Sliding chain Bead-spring model Heterogeneity Diffusion Mean conformation

Experimental tomographic methods for analysing flow dynamics of gas-oil- water flows in horizontal pipeline

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Journal of Hydrodynamics 2016年第6期28卷 1018-1021页

作者： qiang WANG Jiri POLANSKY Bishal KARKI Mi WANG Kent wei Changhua qiu Asaad KENBAR David MILLINGTON University of Leeds Leeds LS2 9JT UK Industrial Tomography System plc Manchester M3 3JZ UK NEL Glasgow G75 0QF UK

Gas-oil-water three phase flow is of practical significance in oil and gas industries. An insight into the dynamics of such multiphase flows is significantly valuable to obtain optimal design parameters and operational conditions. Since flow patterns are sensitive to pipe geometry, flow conditions and thermophysical properties of fluid, it is extremely challenging to provide a universal solution for visualisation of three phase horizontal flows. This study deals with a fully developed, turbulent three phase flow and presents the outcomes of electrical tomographic imaging techniques to visualise gas-oil-water flows in a horizontal pipeline.

关键词： multiphase flow regimes electrical tomography bubbly flow mapping Boolean logic recognition proper orthogonal decomposition method

Vanadium(V)reduction by using a by-product of the yellow phosphorus industry

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Chinese Journal of Chemical Engineering 2023年第10期62卷 150-158页

作者： Baibin Yang Shihong Chen Haowen Ren Yang qiu Chong Chen Yong Guo Chunhui Luo qiang Zhao wei Yang School of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource&HydropowerSichuan UniversityChengdu 610065China

Release of vanadium(V)from industry has threatened the environment and human *** this paper,a removal method of vanadium(V)is proposed using a by-product of the yellow phosphorus industry(phosphorus-iron)as a reducing *** thermodynamics analysis shows that the Gibbs free energy is always negative from 0 to 100℃,indicating a spontaneous *** of the phosphorus-iron slag/sulfuric acid dosage and temperature on the removal efficiency is comprehensively studied,and the kinetics parameters are calculated based on a quasi-first order reaction kinetics *** indicate that vanadium(V)can be entirely reduced by using phosphorus-iron slag,the frequency factor and apparent activation energy are 3.23×10^(9)min^(-1)and 64.50 ***^(-1) for vanadium(V)*** on above results,a lab-scale reactor is constructed and achieves a removal efficiency of~100%and a treatment capacity of 200 ml vanadium(V)solution(2 g.L^(-1))within 3 *** work demonstrates the feasibility of vanadium(V)reduction using phosphorus-iron slag as a reducing agent in applications.

关键词： Vanadium Phosphorus-iron slag Thermodynamics Kinetics Reduction

Experimental study on shock interaction control of double wedge in high-enthalpy hypersonic flow subject to plasma synthetic jet

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Chinese Journal of Aeronautics 2024年第4期37卷 151-165页

作者： Xuzhen XIE qiang LIU Yan ZHOU Zhenbing LUO wei XIE Guanghui BAI Kai LUO qiu WANG Jianjun WU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Academy of Launch Vehicle Technology Beijing 100076China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The hypersonic shock-shock interaction flow field at double-wedge geometries controlled by plasma synthetic jet actuator is experimentally studied in a Ma = 8 high-enthalpy shock tunnel with the purpose of exploring a novel technique for reducing surface heat flux in a real flight environment. The results demonstrate that increasing the discharge energy is advantageous in eliminating the shock wave, shifting the shock wave interaction point, and shortening the control response time. The oblique shock wave can be completely removed when the actuator's discharge energy grows from 0.4 J to 11.5 J, and the displacement of the shock wave interaction point increases by 124.56%, while the controlled response time is shortened by 30 μs. Besides, the reduction in diameter of the jet exit is firstly proved to have a negative impact on energy deposition in a working environment with incoming flow, which reduces the discharge energy and hence decreases the control effect. The shock wave control response time lengthens when the jet exits away from the second wedge. Along with comparing the change in wall heat flux at the second wedge over time, the control effect of plasma synthetic jet actuator with and without inflation is also analyzed. When plasma synthetic jet works in inflatable mode, both the ability to eliminate shock waves and the shifting effect of the shock wave interaction point are increased significantly, and the wall heat flux is also reduced.

关键词： Hypersonic flow High-enthalpy flow Plasma synthetic jet Shock wave Flow control

Stochastic optimal control of cable vibration in plane by using axial support motion

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Acta Mechanica Sinica 2011年第4期27卷 578-586页

作者： Ming Zhao wei-qiu Zhu Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University 310027 Hangzhou China

A stochastic optimal control strategy for a slightly sagged cable using support motion in the cable axial direction is proposed. The nonlinear equation of cable motion in plane is derived and reduced to the equations for the first two modes of cable vibration by using the Galerkin method. The partially averaged Ito equation for controlled system energy is further derived by applying the stochastic averaging method for quasi-non-integrable Hamiltonian systems. The dynamical programming equation for the controlled system energy with a performance index is established by applying the stochastic dynamical programming principle and a stochastic optimal control law is obtained through solving the dynamical programming equation. A bilinear controller by using the direct method of Lyapunov is introduced. The comparison between the two controllers shows that the proposed stochastic optimal control strategy is superior to the bilinear control strategy in terms of higher control effectiveness and efficiency.

关键词： Stay cable Active control - Stochastic optimalcontrol Dynamical programming principle

Organic-rich rocks;Paleoenvironment;Lucaogou Formation;Jimusar Sag;Junggar Basin

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Petroleum Science 2019年第4期16卷 763-775页

作者： Chang-Sheng Qu Long-wei qiu Ying-Chang Cao Yong-qiang Yang Kuan-Hong Yu School of Geosciences China University of PetroleumQingdao 266580ShandongChina Shandong University of Science and Technology Qingdao 266590ShandongChina Key Laboratory of Deep Oil and Gas Geology and Geophysics (China University of Petroleum)Ministry of EducationQingdao 266580ShandongChina

The Lucaogou Formation in the Jimusar Sag of the eastern Junggar Basin is an important sedimentary stratum accumulating huge amounts of lacustrine tight oil in China, where organic-rich rocks are commonly observed. Focusing on the Lucaogou Formation, a precise analysis of the inorganic and organic petrology and the inorganic geochemistry characteristics was conducted. The paleoclimate and paleoenvironment during sedimentation of the Lucaogou Formation were established,and the key factors that were controlling the accumulation of organic matter during this time were identified. The results of this study suggest that during the sedimentation of the Lucaogou Formation, the paleoclimate periodically changed from a humid environment to an arid environment. As a result, the salinity of the water and the redox environment *** the sedimentation period, the lake showed su cient nutrient supplies and a high primary productivity. The interval studies in the Lucaogou Formation were divided into five sedimentary cycles, where the first, second, and fifth sedimentary cycles consisted of cyclical paleoclimate fluctuations varied from a humid environment to an arid environment and shifted back to a humid environment with levels of salinity from low to high and decreased again. The third and fourth cycles have cyclical fluctuations from a humid to an arid environment and corresponding salinity variation between low and high *** the period when organic-rich rocks in the Lucaogou Formation deposited in the Jimusar Sag, the paleoclimate and the water body were suitable for lower aquatic organisms to flourish. As a result, its paleoproductivity was high, especially during the early period of each cycle. A quiet deep water body is likely to form an anoxic environment at the bottom and is also good for accumulation and preservation of organisms. Fine-grained sediments were accumulated at a low deposition rate, with a low dilution of organic matter. Therefore, high

关键词： Organic-rich rocks Paleoenvironment Lucaogou Formation Jimusar Sag Junggar Basin

Analysis of the penalty version of the Arlequin framework for the prediction of structural responses with large deformations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 552-560页

作者： Hua QIAO wei-qiu CHEN Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China

The Arlequin framework proposed by Ben Dhia in 1998 is a flexible and robust method for conducting global/local analysis of structures and materials.A penalty version of the Arlequin framework for the study of structural problems involving large deformation is considered *** implementation of the penalty-based Arlequin framework into ABAQUS is then explored and the corresponding Arlequin user element subroutine is *** nonlinear simulations of a cantilever beam and a shallow arch are conducted and the choice of the coupling operator with an appropriate penalty parameter is *** numerical results justify the feasibility of the proposed method,ensuring its further application to more complicated problems involving geometric or material nonlinearities.

关键词： Global/Local analysis Geometric nonlinear analysis Penalty-based Arlequin method User defined element

Science Letters:On numerical calculation in symplectic approach for elasticity problems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 583-588页

作者： Li ZHAO wei-qiu CHEN Department of Civil Engineering Zhejiang University Hangzhou 310027 China

The symplectic approach proposed and developed by Zhong et al. in 1990s for elasticity problems is a rational analytical method, in which ample experience is not needed as in the conventional semi-inverse method. In the symplectic space, elasticity problems can be solved using the method of separation of variables along with the eigenfunction expansion technique, as in traditional Fourier analysis. The eigensolutions include those corresponding to zero and nonzero eigenvalues. The latter group can be further divided into α-and β-sets. This paper reformulates the form of β-set eigensolutions to achieve the stability of numerical calculation, which is very important to obtain accurate results within the symplectic frame. An example is finally given and numerical results are compared and discussed.

关键词： Symplectic approach Eigenfunction Numerical stability Elasticity problems

New flexible CsPbBr_(3)-based scintillator for X-ray tomography

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Nuclear Science and Techniques 2022年第8期33卷 34-44页

作者： Zhi-wei Lü Gong-Xiang wei Han-qiu Wang Yu Guan Ning Jiang Yun-Yan Liu Zhao Li Hua Qin Hui-qiang Liu School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China

The evolution of lead halide perovskites used for X-ray imaging scintillators has been facilitated by the development of solution-processable semiconductors characterized by large-area,flexible,fast *** stability and durability of these new perovskites are insufficient to achieve extended computed tomography scanning times with hard *** this study,we fabricated a self-assembled CsPbBr_(3)-based scintillator film with a flexible large-area uniform thickness using a new roomtemperature solution-processable *** sensitivity and responsivity of X-ray photon conversion were quantitatively measured and showed a good linear response relationship suitable for X-ray *** also demonstrated,for the first time,that the self-assembled CsPbBr_(3)-based scintillator has good stability for hard X-ray ***,such an inexpensive solution-processed semiconductor easily prepared at room temperature can be used as a hard X-ray scintillator and equipped with flexible CsPbBr3-based X-ray *** has great potential in three-dimensional high-resolution phase-contrast X-ray-imaging applications in biomedicine and material science because of its heavy Pb and Br atoms.

关键词： X-ray scintillator X-ray illumination Computed tomography CsPbBr_(3)-based film perovskite Solution-processable semiconductor