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Synthesis and Crystal Structure of an Ion-pair Supramolecular Associate 2,9-Diformyl-1,10-phenanthrolinebis-(2,6-dimethylanil)cobalt(Ⅱ) Perchlorate

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Chinese Journal of Structural Chemistry 2006年第7期25卷 861-865页

作者： LI gang JIE Su-yun TANG Ning SUN Wen-Hua State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China Key Laboratory of Engineering Plastics Institute of Chemistry The Chinese Academy of Sciences Beijing 100080 China

2,9-Diformyl-l, 10-phenanthrolinebis（2,6-dimethylanil）cobalt（Ⅱ） perchlorate was synthesized and demonstrated to be [COL2][ClO4]2 by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group C2/c with a = 22.294（4）, b = 15.122（3）, c = 20.640（4） A, β = 119.618（4）°, V = 6048.9（19） A^3, C63H52Cl2CoN9O9, Mr= 1208.97, F（000） = 2504, De= 1.328g/cm^3, Z = 4, μ= 0.436, the final R = 0.0712 and wR = 0.1718 for 1734 observed reflections （I 〉 2σ（I））. In its solid state the helical polymeric chains are supramolecularly associated through intermolecular and interionic hydrogen bonding interactions.

关键词： 1,10-phenanthroline cobalt complex crystal structure hydrogen bond

Kinematics of Non-axially Positioned Vesicles through a Pore

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Chinese Journal of Polymer Science 2020年第7期38卷 776-783,I0008页

作者： yun-Long Han Ming-Ming ding Rui Li Tong-Fei Shi School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

We employ finite element method to investigate the kinematics of non-axially positioned vesicles through a *** complete the coupling between fluid flow and the vesicle membranes,we use the fluid structure interactions with the arbitrary Lagrangian Eulerian *** results demonstrate that the vesicles show different deformations in migration process,in turn an oblique ellipse-shape,slipper-shape,*** find that the rotation angle of non-axially positioned vesicles mainly shows the trend of increase,besides the small fluctuation induced by deformation ***,when the vesicles move towards the axis of the channel,the rotation angle exhibits a decrease because of the decrease of the shear ***,rotation of axially positioned vesicles hardly occur due to symmetrical shear *** results further indicate that the rotation is faster nearby the pore for non-axially positioned *** work answers the mapping between the positions of vesicles and deformed states,as well as the change of rotation angle and rotation velocity,which can provide helpful information on the utilization of vesicles in pharmaceutical,chemical,and physiological processes.

关键词： Vesicles Narrow pore Rotation angle Rotation velocity

A Machine Learning Study of Polymer-Solvent Interactions

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Chinese Journal of Polymer Science 2022年第7期40卷 834-842页

作者： Ting-Li Liu Lun-Yang Liu Fang ding yun-Qi Li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polymer-solvent interaction is a fundamentally important concept routinely described by the Flory-Huggins interaction(χ),Hildebrand solubility(Δδ)and the relative energy difference(RED)determined from Hansen solubility in experimental,theoretical and simulation *** we performed a machine learning study based on a comprehensive and representative dataset covering the interaction pairs from 81polymers and 1221 *** regression models provide the coefficients of determination in the range of 0.86-0.94 and the classification models deliver the area under the receiver operating characteristic curve(AUCs)better than *** models were integrated into a newly developed software *** features including Log P,molar volume and dipole are identified,and their non-linear,nonmonotonic contributions to polymer-solvent interactions are *** widely known“like-dissolve-like”rule and two broadly used empirical equations to estimateχas a function of temperature or Hansen solubility are also evaluated,and the polymer-specified constants are *** study provides a quantitative reference and a tool to understand and utilize the concept of polymer-solvent interactions.

关键词： Flory-Huggins interaction Hildebrand solubility Hansen solubility Machine learning Prediction

A Dynamic XML-NS View Based Approach for the Extensible Integration of Web Data Sources

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 647-651页

作者： WUWei LUZheng-ding LIRui-xuan WANGZhi-gang SchoolofComputerScienceandTechnology.HuazhongUniversityofScienceandTechnology Wuhan430071Hubei.China

We propose a three-step technique to achieve this purpose. First, we utilize a collection of XML namespaces organized into hierarchical structure as a medium for expressing data semantics. Second, we define the format of resource descriptor for the information source discovery scheme so that we can dynamically register and/or deregister the Web data sources on the fly. Third, we employ an inverted-index mechanism to identify the subset of information sources that are relevant to a particular user query. We describe the design, architecture, and implementation of our approach—IWDS, and illustrate its use through case examples. Key words integration - heterogeneity - Web data source - XML namespace CLC number TP 311.13 Foundation item: Supported by the National Key Technologies R&D Program of China(2002BA103A04)Biography: WU Wei (1975-), male, Ph.D candidate, research direction: information integration, distribute computing

关键词： integration heterogeneity Web data source XML namespace

MELINIKOV’S METHOD FOR NON-LINER ROLLING MOTIONS OF A FLOODED SHIP

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Journal of Hydrodynamics 2005年第5期17卷 580-584页

作者： PU Jin-yun ZHANG Wei-kang JIN Tao JI gang College of Ship and Power University of Naval Engineering Wuhan 430033 China

To investigate the rolling motions of a flooded ship, non linear coupled dynamics of roll and flooded water are derived using Lagrange＇s principle. Decoupling the coupied equations gives a single-freedom ordinary differential equation, which can describe the rolling motion of the flooded ship. Melinkov＇s method is used to predict the chaos behavior of the ship. Numerical computations are performed for three statuses of a ship model. The comparison of the results shows that the more cabins flooded, the more likely a chaos phenomenon will appear.

关键词： ship flooding roll Melinikov' method

Fully Self-Consistency in Relativistic Random Phase Approximation

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Chinese Physics Letters 2012年第11期29卷 40-42页

作者： YANG ding CAO Li-gang MA Zhong-Yu School of Science Communication University of ChinaBeijing 100024 Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of LanzhouLanzhou 730000 China Institute of Atomic Energy P.O.Box 275(18)Beijing 102413

Fully self-consistent relativistic random phase approximation(RRPA)is built on the relativistic mean field ground state with a non-linear relativistic *** consistency requires that the same effective interaction is adopted to simultaneously describe both the ground states and the excited states of the *** and accurate numerical results of the nuclear giant resonances obtained in the RRPA require fully consistent *** some excitation modes they are extremely sensitive to consistent treatment,e.g.,such as isoscalar giant monopole and dipole resonances(ISGMR and ISGDR).In this work we perform the numerical calculations in the case of ISGDR for ^(208)Pb and check the *** spurious state in the ISGDR vanishes once the full self-consistency is achieved.

关键词： relativistic consistency Approximation

A Fast Approach for Time Optimal and Smooth Trajectory Planning of Robot Manipulators

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Journal of Harbin Institute of Technology(New Series) 2016年第5期23卷 23-31页

作者： gang Liu Chao yun Robotics Institute Beihang University

In this paper, a fast approach to generate time optimal and smooth trajectory has been developed and tested. Minimum time is critical for the productivity in industrial applications. Meanwhile, smooth trajectories based on cubic splines are desirable for their ability to limit vibrations and ensure the continuity of position, velocity and acceleration during the robot movement. The main feature of the approach is a satisfactory solution that can be obtained by a local modification process among each intermal between two consecutive via-points. An analytical formulation simplifies the approach to smooth trajectory and few,iterations are enough to determine the correct values. The approach can be applied in many robot manipulators which require high performance on time and smooth. The simulation and application of the approach on a palletizer robot are performed, and the experimental results provide evidence that the approach can realize the robot manipulators more efficiency and high smooth performance.

关键词： trajectory planning cubic spline kinematic constraints interval anatysis time optimal smoothtechnique

Asymmetric Fuzzy Control of a Positive and Negative Pneumatic Pressure Servo System

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1438-1446页

作者： gang Yang Jing-Min Du Xiao-yun Fu Bao-Ren Li School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074China

The pneumatic pressure control systems have been used in some fields. However, the researches on pneumatic pressure control mainly focus on constant pressure regulation. Poor dynamic characteristics and strong nonlinearity of such systems limit its application in the field of pressure tracking control. In order to meet the demand of generating dynamic pressure signal in the application of the hardware-in-the-loop simulation of aerospace engineering, a positive and negative pneumatic pressure servo system is provided to implement dynamic adjustment of sealed chamber pressure. A mathematical model is established with simulation and experiment being implemented afterwards to discuss the characteristics of the system, which shows serious asymmetry in the process of charging and discharging. Based on the analysis of the system dynamics, a fuzzy proportional integral derivative （PID） controller with asymmetric fuzzy compensator is proposed. Different from conventional adjusting mecha- nisms employing the error and change in error of the controlled variable as input parameters, the current cham- ber pressure and charging or discharging state are chosen as inputs of the compensator, which improves adaptability. To verify the effectiveness and performance of the pro- posed controller, the comparison experiments tracking sinusoidal and square wave commands are conducted. Experimental results show that the proposed controller can obtain better dynamic performance and relatively consis- tent control performance across the scope of work （2-140 kPa）. The research proposes a fuzzy control method to overcome asymmetry and enhance adaptability for the positive and negative pneumatic pressure servo system.

关键词： Pneumatic pressure control system Positiveand negative pressure Asymmetric control Fuzzy control

Experimental study of drag reduction characteristics related to the multifactor coupling of a bionic jet surface

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Journal of Hydrodynamics 2019年第1期31卷 186-194页

作者： yun-qing Gu Song-wei Yu Jie-gang Mou Tian-xing Fan Shui-hua Zheng gang Zhao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

To study the drag reduction of a jet surface,an experiment is conducted with a gyrorotor *** aim of this study is to analyze the influence of the jet aperture,the jet angle and the rotational velocity coupled with the jet velocity on the friction torque acting on a jet surface model by using a jet surface drag reduction testing experimental *** drag reduction characteristics of the jet surface are also *** results show that the maximum drag reduction rate is attained when the jet diameter is 5 mm and the jet velocity is 1.2 m/*** influence of the jet velocity on the drag reduction rate decreases as the diameter ***,the maximum drag reduction rate can be attained when the angle of the jet is 30° and the velocity of the jet is 1.0 m/*** the jet diameter is small,the influence of the jet velocity on the drag reduction rate is small,whereas the maximum drag reduction rate is attained when the jet angle is 30° and the jet velocity is 1.0 m/*** the jet angle is 15°,the drag reduction rate fluctuation is *** maximum drag reduction rate is attained when the rotational velocity is 2 100 r/min and the jet velocity is 1.0 m/*** results show that the best scheme is A2B2D3 A maximum drag reduction rate of 8.57% can be *** effective control of the jet effect on the separation of the boundary layer demonstrates the drag reduction principle of a bionic jet surface.

关键词： Drag reduction bionic jet surface friction torque coupling experiment