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Chinese Annals of Mathematics,Series B 2008年第4期29卷 441-458页

作者： Junping yin zhong TAN Department of Mathematics Xiamen University Xiamen 361005 Fujian China.

The authors prove two global existence results of strong solutions of the isentropic compressible Navier-Stokes-Poisson equations in one-dimensional bounded intervals. The first result shows only the existence. And the second one shows the existence and uniqueness result based on the first result, but the uniqueness requires some compatibility condition. In this paper the initial vacuum is allowed, and T is bounded.

关键词： Global strong solutions Navier-Stokes-Poisson equations Existence and uniqueness

Handedness-inverted polymorphic helical assembly and circularly polarized luminescence of chiral platinum complexes

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Science China Chemistry 2021年第5期64卷 788-799页

作者： zhong-Liang Gong Yu-wu zhong Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of PhotochemistryCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

Circularly polarized luminescence(CPL)materials have potential applications in three-dimensional(3D)displays,quantum encryption,and optical *** development of single-component CPL materials with polymorphic assembly and handedness inversion remains a significant ***,we present the access of such materials by controlling the underlying assembly pathway of well-designed chiral emitters.A pair of enantiomeric platinum complexes(R)-1 and(S)-1 decorated with a chiralα-methylbenzyl isocyanide ligand were *** using the mixed-solvent(THF/n-hexane,THF=tetrahydrofuran)or high-concentration condition,these complexes were found to assemble via a cooperative or isodesmic pathway with significantly enhanced yellow or red emission,*** aggregate samples obtained via these conditions show efficient CPL(dissymmery factor|glum|>0.02,emission quantum yieldΦ>20%).Interestingly,different assembly pathway leads to helical nanoribbons or nanofibers with opposite handedness from the complex with the same molecular *** has been unambiguously and consistently manifested by circular dichroism and CPL spectral analysis and transmission electron,scanning electron,and atomic force microscope *** work demonstrates an appealing example of constructing polymorphic helical architectures with highly efficient CPL and inverted handedness thanks to the excellent assembly and emission of platinum complexes.

关键词： self-assembly nanostructures circularly polarized luminescence chiral materials platinum complexes

A novel model for the proppant equilibrium height in hydraulic fractures for slickwater treatments

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Petroleum Science 2022年第1期19卷 254-263页

作者： zhong-Wei wu Chuan-Zhi Cui yin-Zhu Ye Xiang-Zhi Cheng Japan Trivedi Shui-Qing-Shan Lu yin Qian College of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina Research Institute of Petroleum Exploration&Development PetroChinaBeijing100083China School of Mining and Petroleum Department of Civil and Environmental EngineeringUniversity of AlbertaEdmontonABT6G 2R3Canada

The proppant equilibrium height is the basis of investigating proppant distributions in artificial fractures and has a great significant influence on hydraulic fracturing *** are two shortcomings of current research on proppant equilibrium heights,one of which is that the effect of fracture widths is neglected when calculating the settling velocity and another of which is that the settling bed height is a constant when building the settling bed height growth rate *** fill those two shortcomings,this work provides a novel model for the proppant equilibrium height in hydraulic fractures for slickwater treatments.A comparison between the results obtained from the novel model and the published model and experimental results indicates that the proposed model is *** the sensitivity analysis,it is concluded that the proppant equilibrium height increases with an increasing proppant *** proppant equilibrium height decreases with an increase in the slickwater injection rate and increases with an increase in the proppant injection *** increase in proppant diameter results in an increasing the friction factor,which makes proppant equilibrium heights ***,the increase in proppant sizes results in an increase in proppant settling rates,which makes the proppant equilibrium height *** the effect of the proppant diameter on settling rates is more significant than that on friction factors,the equilibrium height increases with an increasing proppant *** work provides a research basis of proppant distributions during the hydraulic fracture.

关键词： Equilibrium height Proppant settling Fracture width Slickwater Shale and tight reservoirs

Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： yin wu Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

Variable Clearance Characteristics of High Subsonic Compressor Cascades with Blade Tip Winglets

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Journal of Thermal Science 2022年第2期31卷 495-510页

作者： wu Wanyang zhong Jingjun Merchant Marine College Shanghai Maritime UniversityShanghai 201306China

The gas turbine is the main power equipment for naval ship and special civil ship,while the compressor is one of the core structures of the gas *** existing tip clearance could prevent the compressor blade and casing ***,the flow loss in the tip region caused by the tip clearance will degrade the performance of the *** improve the variable clearance characteristics of the high subsonic compressor cascades,the cascades with tip clearances of 1%,2%and 3%chord length are studied through experimental measurements and numerical *** research results prove that the pressure surface tip winglet can cause a significant improvement effect under most working *** the blade tip clearance size is gradually increasing within a reasonable range,the improvement effect becomes more remarkable,and the optimal tip winglet case *** tip clearance is 1%chord length,the PTW1.0 case(the width of the pressure surface tip winglet is 1.0 time of the original tip)reduces the flow loss by 3.09%compared with the NTW case(No Tip Winglet).When tip clearance is 2%chord length,the flow loss of PTW1.5 case(the width of the pressure surface tip winglet is 1.5 times of the original tip)is reduced by 3.46%.When tip clearance is 3%chord length,all alternative tip winglets reduce the total pressure loss,and PTW2.0 case(the width of the pressure surface tip winglet is 2.0 times of the original tip)is the best choice,which has a 6.53%degree of improvement.

关键词： high subsonic compressor blade tip winglet tip clearance pressure surface experimental measurement

Iterative Learning Disturbance Observer Based Attitude Stabilization of Flexible Spacecraft Subject to Complex Disturbances and Measurement Noises

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IEEE/CAA Journal of Automatica Sinica 2021年第9期8卷 1576-1587页

作者： Tongfu He zhong wu School of Instrumentation and Optoelectronics Engineering Beihang UniversityBeijing 100191China

To realize high-precision attitude stabilization of a flexible spacecraft in the presence of complex disturbances and measurement noises,an iterative learning disturbance observer(ILDO)is presented in this ***,a dynamic model of disturbance is built by augmenting the integral of the lumped disturbance as a *** on it,ILDO is designed by introducing iterative learning ***,comparative analyses of ILDO and traditional disturbance observers are carried out in frequency *** demonstrates that ILDO combines the advantages of high accuracy in disturbance estimation and favorable robustness to measurement *** that,an ILDO based composite controller is designed to stabilize the spacecraft ***,the effectiveness of the proposed control scheme is verified by simulations.

关键词： Disturbance observer iterative learning measure-ment noise spacecraft attitude control

Structure–activity relationship and mechanisms of reagents used in scheelite flotation

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Rare Metals 2015年第12期34卷 882-887页

作者： Wan-zhong yin Ji-Zhen Wang zhong-Mei Sun School of Resource and Civil Engineering Northeastern University Design & Research Institute of Zijin

Effects of carboxylic acid collector, benzohydroxamic acid (BHA), sodium hexametaphosphate (SHAP), sodium silicate, and oxalic acid on scheelite flotation were studied through flotation tests, quantum chemical calculation, and flotation solution computational chemistry. In terms of the calculation results, the relationship between chemical reactions occurring on the scheelite surface and molecular structures of the reagents were analyzed. The results show that BHA and carboxylic acid collectors interact with scheelite in different forms and the recovery of scheelite using sodium oleate as collector declines successively from SHAP, sodium silicate, to oxalic acid. Moreover, it is found that the performance of depressant in scheelite flotation is directly related to the group electronegativity, indicating that the latter is a dominant factor that determines the former. These findings will be helpful to the academic research communities of scheelite flotation.

关键词： Scheelite Flotation Flotation reagents Structure–activity relationship

Characterization of Interaction Between Raltitrexed and Bovine Serum Albumin by Optical Spectroscopic Techniques

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Chemical Research in Chinese Universities 2012年第6期28卷 963-970页

作者： ZHANG Jia-xing yin Zong-ning wu Wei WANG zhong-xia HE Rui wu Zhao-xu Key Laboratory of Drug Targeting and Novel Drug Delivery Systems West China School of Pharmacy Sichuan University Chengdu 610041 P. R. China School of Pharmacy Fudan University Shanghai 201203 P. R. China

The interaction of raltitrexed（RTX） with bovine serum albumin（BSA） was investigated by steady state/lifetime fluorescence spectroscopy and circular dichroism（CD） spectroscopy under the simulative physiological *** results of fluorescence titration reveal that RTX could strongly quench the intrinsic fluorescence of BSA via a static quenching *** obtained binding constant K A of RTX with BSA was 478630 and 44259 L/mol at 298 and 310 K,*** to van＇t Hoff equation,the thermodynamic parameters ΔH,ΔG and ΔS were calculated,indicating that hydrophobic forces were the predominant intermolecular forces in stabilizing the *** binding process was a spontaneous process,in which Gibbs free energy change was *** to F rster＇s non-radioactive energy transfer theory,the distance r between donor（BSA） and acceptor（RTX） was 3.82 nm,suggesting that the energy transfer from BSA to RTX occurred with high *** experiment and the number of binding sites calculation confirmed that RTX could bind to the site-I of ***,the effects of pH and some metal ions on the interaction of RTX with BSA were also *** results of synchronous fluorescence and CD spectra show that the RTX-BSA binding induced conformational changes in BSA.

关键词： Raltitrexed(RTX) Bovine serum albumin(BSA) Fluorescence quenching Fluorescence lifetime Circular dichroism(CD) spectroscopy

Cuckoo search with varied scaling factor

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Frontiers of Computer Science 2015年第4期9卷 623-635页

作者： Lijin WANG Yilong yin Yiwen zhong School of Computer Science and Technology Shandong University Jinan 250101 China College of Computer and Information Science Fujian Agriculture and Forestry University Fuzhou 350002 China School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China

Cuckoo search （CS）, inspired by the obligate brood parasitic behavior of some cuckoo species, iteratively uses L6vy flights random walk （LFRW） and biased/selective random walk （BSRW） to search for new solutions. In this study, we seek a simple strategy to set the scaling factor in LFRW, which can vary the scaling factor to achieve better performance. However, choosing the best scaling factor for each problem is intractable. Thus, we propose a varied scal- ing factor （VSF） strategy that samples a value from the range [0,1] uniformly at random for each iteration. In addition, we integrate the VSF strategy into several advanced CS vari- ants. Extensive experiments are conducted on three groups of benchmark functions including 18 common test functions, 25 functions proposed in CEC 2005, and 28 functions intro- duced in CEC 2013. Experimental results demonstrate the ef- fectiveness of the VSF strategy.

关键词： cuckoo search algorithm uniform distribution,random sampling scaling factor function optimization prob-lems

ARNOLD CIRCULATION AND MULTI-OPTIMAL DYNAMIC CONTROLLING MECHANISMS IN DRAGONFLY WINGS

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Acta Mechanica Solida Sinica 2013年第3期26卷 237-244页

作者： Hongxiao Zhao Yajun yin Zheng zhong School of Aerospace Engineering and Applied Mechanics Tongji University School of Aerospace Department of Engineering MechanicsTsinghua University

This paper aims to reveal the multi-optimal mechanisms for dynamic control in drag- onfly wings. By combining the Arnold circulation with such micro/nano structures as the hollow inside constructions of the pterostigma, veins and spikes, dragonfly wings can create variable mass, variable rotating inertia and variable natural frequency. This marvelous ability enables dragonflies to overcome the contradictory requirements of both light-weight-wing and heavy-weight-wing, and displays the multi-optimal mechanisms for the excellent flying ability and dynamic control capac- ity of dragonflies. These results provide new perspectives for understanding the wings＇ functions and new inspirations for bionic manufactures.

关键词： dragonfly wings veins and pterostigma Arnold circulation multi-optimal control-ling mechanism