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The research on floe ice force acting on the"Xue Long"icebreaker based on synthetic ice test and virtual mass numerical method

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Journal of Hydrodynamics 2021年第2期33卷 271-281页

作者： Wei Guo Qiao-sheng Zhao yu-kui Tian Wan-chao Zhang State Key Laboratory of Hydrodynamics China Ship Scientific Research CenterWuxi 214082China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

When the ice-going ships advance in the polar region,the navigation in the floe ice region is often encountered,the hull will suffer the high-frequency contact force produced by the floe ice,which will affect the navigation performance of the ***,it is necessary to predict the water and ice force acting on the hull *** this paper,the numerical simulation and experimental verification will be conducted for the polar scientific research ship-"Xue Long".Based on the computational fluid dynamics(CFD)and DEM theory,a virtual mass method is proposed to realize the predicting of the water and ice force and the simulation of the interaction phenomenon between the ice and hull,the numerical method is built to calculate the force acting on the *** the same time,the synthetic ice is used to carry out the experimental research on the advancing straight with different speeds and the oblique navigation with different drift *** optimal virtual mass coefficient is determined through the comparison and analysis of the numerical simulation and test results under typical *** to the optimal virtual mass coefficient,the numerical simulation is carried out with different speeds and drift angles,which is compared with the experiment more *** is found that the virtual mass method based on the combination of CFD and DEM can simulate the overturning and the sliding along the hull of the floe ice vividly,the relative error of the total resistance between model test and numerical method in advancing straight is almost within 10%,while the relative error of the total longitudinal force in oblique navigation is almost within 15%.

关键词： "Xue Long"ship synthetic ice model test computational fluid dynamics(CFD) DEM virtual mass method drift angle

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The precursor compound of two types of ZnSe magic-sized clusters

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Nano Research 2022年第1期15卷 465-474页

作者： Xingxia Yang Meng Zhang Qiu Shen Yang Li Chaoran Luan kui yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China Department of Ophthalmology West China School of MedicineWest China HospitalSichuan UniversityChengdu 610065China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China

Precursor compounds(PCs)link quantum dots(QDs)and magic-sized clusters(MSCs),which is pivotal in the conversion between QDs and ***,for the first time,we report the transformation,synthesis,and composition of a type of ZnSe *** PCs can be directly transformed to two different MSCs with the assistance of octylamine and acetic acid at room *** two types of MSCs exhibit sharp absorption peaks at 299 and 328 nm which are denoted as MSC-299 and *** the preparation of ZnSe PCs,diphenylphosphine(DPP)as an additive plays a key role which not only inhibits the thermal decomposition of Zn precursor,but also acts as a reducing agent to reduce the by-products produced in the *** composition was explored by X-ray photoelectron spectroscopy,energy dispersive spectrometer,matrix-assisted laser desorption/ionization time-of-flight mass spectra with ZnSe PC powder appeared as white powder after purifying by toluene(Tol)and methanol(MeOH).The results indicate that the molar ratio of Zn/Se is 2:1 with a molecular of〜3,350 ***,we propose that the molecular formula of ZnSe PCs is Zn_(32)Se_(16).In addition,at the molecular level,the covalent bond of Zn-Se is formed in ZnSe *** study offers a deeper understanding of the transformation from PCs to MSCs and for the first time proposes the composition of ***,this research provides us with a new understanding of the role of DPP in the synthesis of colloidal semiconductor nanoparticles.

关键词： ZnSe magic-size clusters(MSCs) precursor compounds(PCs) purification composition

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Size matters:Steric hindrance of precursor molecules controlling the evolution of CdSe magic-size clusters and quantum dots

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Nano Research 2022年第9期15卷 8564-8572页

作者： Juan Shen Chaoran Luan Nelson Rowell Yang Li Meng Zhang Xiaoqin Chen kui yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Laboratory of Ethnopharmacology Tissue-orientated Property of Chinese Medicine Key Laboratory of Sichuan ProvinceWest China School of MedicineWest China HospitalSichuan UniversityChengdu 610065China Metrology Research Centre National Research Council CanadaOttawaOntario K1A 0R6Canada Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China

Little is known about how to precisely promote the selective production of either colloidal semiconductor metal chalcogenide(ME),magic-size clusters(MSCs),or quantum dots(QDs).Recently,a two-pathway model has been proposed to comprehend their evolution;here,we reveal for the first time that the size of precursors plays a decisive role in the selected evolution pathway of MSCs and *** the reaction of cadmium myristate(Cd(MA)2)and tri-n-octylphosphine selenide(SeTOP)in 1-octadecene(ODE)as a model system,the size of Cd precursors was manipulated by the steric hindrance of carboxylic acid(RCOOH)*** RCOOH,the reaction produced both CdSe MSCs and QDs(from 100 to 240℃).With RCOOH,the reaction produced MSCs or QDs when R was small(such as CH3−)or large(such as C6H5−),*** to the twopathway model,the selective evolution is attributed to the promotion and suppression of the self-assembly of Cd and Se precursors,*** propose that the addition of carboxylic acid may occur ligand exchange with Cd(MA)2,causing the different sizes of Cd *** results suggest that the size of Cd precursors regulates the self-assemble behavior of the precursors,which dictates the directed evolution of either MSCs or *** present findings bring insights into the two-pathway model,as the size of M and E precursors determine the evolution pathways of MSCs or QDs,the understanding of which is of great fundamental significance toward mechanism-enabled design and predictive synthesis of functional nanomaterials.

关键词： cadmium selenide(CdSe) magic-size clusters(MSCs) quantum dots(QDs) self-assembly steric hindrance

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EFFECT OF DRILLPIPE ROTATION ON BOREHOLE CLEANING FOR EXTENDED REACH WELL

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Journal of Hydrodynamics 2009年第3期21卷 366-372页

作者： WANG Zhi-ming GUO Xiao-le LI Ming HONG yu-kui College of Oil and Gas Engineering China University of Petroleum Beijing 102249 China

Wellbore cleaning is a key technology for the Extended Reach Drilling （ERD）. The success of drilling extended reach wells depends directly upon the quality of wellbore cleaning. The rotation of the drillpipe, and hydraulic and rheological parameters, are the key factors for wellbore cleaning. In this study, Computational Fluid Dynamics （CFD） is applied to simulate solid-liquid two-phase flows in wellbore annulus. The annual flow field with the presence of drillpipe rotation is described through analyzing various rotation conditions. The results indicate that the quasi-spiral flow is the main flow pattern for liquid-solid transport in the horizontal annulus. The influence of rotation on the cuttings transport is also investigated, as the rotation of drillpipe increases the disturbance of liquid to solid in annulus. As a result, the solid flow becomes favorable and the solid volume is reduced. Comparisons with previously published results are also performed to prove the importance of drillpipe rotation in the wellbore clearing for the ERD.

关键词： Extended Reach Drilling (ERD) borehole cleaning solid-liquid two-phase flow drillpipe rotation simulation spiral flow

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Development of aqueous-phase CdSeS magic-size clusters at room temperature and quantum dots at elevated temperatures

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Nano Research 2024年第12期17卷 10529-10535页

作者： Yao Jiang Zhe Wang Shasha Wang Chunchun Zhang Chaoran Luan Xiaoqin Chen kui yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China Analytical&Testing Center Sichuan UniversityChengdu 610065China College of Biomedical Engineering Sichuan UniversityChengdu 610065China

Little is known about the synthesis of colloidal ternary semiconductor magic-size clusters(MSCs)and quantum dots(QDs)in an aqueous *** report here the first synthesis of aqueous-phase CdSeS MSC-380(displaying sharp optical absorption peaking at~380 nm)at room temperature and QDs at elevated *** reaction contains CdCl2·2.5H_(2)O,3-mercaptopropionic acid(MPA,HS-(CH_(2))2-COOH),selenourea(SeU,NH_(2)-C(Se)-NH_(2)),and thioacetamide(TAA,CH3-C(S)-NH_(2)).Prior to the nucleation and growth(N/G)of QDs,there are clusters formed at 25℃.The prenucleation-stage clusters are the precursor compound of CdSeS MSC-380(PC-380).The PC is relatively transparent in optical absorption;in the presence of a primary amine butylamine(BTA,CH3-(CH_(2))3-NH_(2)),the PC transforms to absorbing CdSeS *** 80℃,the PC decreases and the N/G of CdSeS QDs *** present study paves the way to the aqueous-phase synthesis of ternary CdSeS MSCs and QDs,providing an in-depth understanding of the cluster formation in the prenucleation stage of CdSeS QDs.

关键词： aqueous phase precursor compound(PC) magic-size cluster(MSC) quantum dot(QD) cadmium selenide sulfide

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Effects of process parameters on periodic impact force exerting on cutting tool in ultrasonic vibration-assisted oblique turning

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Advances in Manufacturing 2022年第3期10卷 411-427页

作者： Long-Xu Yao Zhan-Qiang Liu Qing-Hua Song Bing Wang yu-kui Cai School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education/Key National Demonstration Center for Experimental Mechanical Engineering Education Jinan 250061People's Republic of China

During ultrasonic vibration-assisted machining,the large impact force induced by tool-workpiece reengagement(TWR)is an important factor that affects tool ***,mechanical analysis into process factors that affect the impact force and their influencing mechanisms are ***,a prediction model for the instantaneous cutting force during both TWR and the stable turning process,which depends on the process parameters and material properties,is firstly proposed based on the kinematic and dynamic analysis of ultrasonic vibration-assisted oblique turning(UVAOT).The results calculated using the developed cutting force model agree well with the experimental results presented in the ***,the linear change law of the instantaneous cutting force with cutting time during the actual TWR is clarified using the proposed *** effect of the UVAOT process parameters on the average impact force during the periodic TWR process is discussed,and the influence mechanism is analyzed from the perspective of mechanics.A positive linear correlation is discovered between the feed speed and average impact *** ultrasonic amplitude and cutting speed do not significantly affect the average impact force of the new sharp cutting *** findings are consistent with the experimental observations of tool chipping and are applicable to select process parameters for reducing tool chipping during UVAOT.

关键词： Kinematics Dynamics Ultrasonic vibrationassisted oblique turning(UVAOT) Impact force Cutting force

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Precursor compound enabled formation of aqueous-phase CdSe magic-size clusters at room temperature

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Nano Research 2022年第3期15卷 2634-2642页

作者： Min Zhao Qingyuan Chen Yongcheng Zhu yuehui Liu Chunchun Zhang Gang Jiang Meng Zhang kui yu School of Chemical Engineering Sichuan UniversityChengdu 610065China Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China Analytical&Testing Center Sichuan UniversityChengdu 610065China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China

The formation pathway of aqueous-phase colloidal semiconductor magic-size clusters(MSCs)remains *** the present work,we demonstrate,for the first time,a precursor compound(PC)-enabled formation pathway of aqueous-phase CdSe MSCs exhibiting a sharp absorption peaking at about 420 nm(MSC-420).The CdSe MSC-420 is synthesized with CdCl2 and selenourea as the respective Cd and Se sources,and with 3-mercaptopropionic acid or L-cysteine as a *** featureless CdSe PCs form first in the aqueous reaction batches,which transform to MSC-420 in the presence of primary *** coordination between primary amine and Cd^(2+)on PCs may be responsible to the PC-to-MSC *** increasing the reactant concentrations or decreasing the CdCl_(2)-ligand feed molar ratios,the Cd precursor self-assembles into large aggregates,which may encapsulate the resulting CdSe PCs and inhibit their transformation to *** present study sheds essential light on the syntheses and formation mechanisms of nanocrystals.

关键词： aqueous magic-size cluster precursor compound formation pathway self-assembly precursor configuration

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Molecularly imprinted macroporous monolithic materials for protein recognition

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Chinese Chemical Letters 2011年第11期22卷 1351-1354页

作者： Qi Liang Deng Yan Li Li Li Hua Zhang yu kui Zhang Department of Science Tianjin University of Science and Technology Tianjin 300222 China National Chromatograp＇hic R. ＆ A. Center Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Synthetic materials that can specifically recognize proteins will find wide application in many *** this report,bovine serum albumin was chosen as the template *** and N,N＇-methylenebisacrylamide were employed as the functional and cross-linker monomers,*** imprinted macroporous monolithic materials that can preferentially bind the template protein in an aqueous environment were prepared by combination of molecular imprinting technique and freezing/thawing preparation *** resulted imprinted macroporous monolithic columns were evaluated by utilizing as stationary phase in high performance liquid chromatography and solid-phase extraction *** experimental results indicated that the imprinted macroporous monolithic column exhibited good recognition for template protein,as compared with the control protein（hemoglobin）,whereas the non-imprinted polymer（prepared under the same conditions except without addition template protein） had no selective properties.

关键词： Molecularly imprinted polymers Protein Monolithic column High performance liquid chromatography

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Formation of ZnSe magic-size clusters displaying optical absorption doublets from prenucleation clusters

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Nano Research 2024年第7期17卷 6741-6748页

作者： Dingyu Zhao Shasha Wang Jiawei Xue Chunchun Zhang Shanling Wang Xiaoqin Chen Chaoran Luan kui yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China Analytical&Testing Center Sichuan UniversityChengdu 610065China College of Biomedical Engineering Sichuan UniversityChengdu 610065China

The formation pathway of colloidal semiconductor ZnSe magic-size clusters(MSCs)in a reaction that display an optical absorption doublet remains poorly *** reaction of Zn(OAc)_(2)/OLA(made from zinc acetate and oleylamine)and tri-noctylphosphine selenide(SeTOP)in OLA in the presence of diphenylphosphine(HPPh_(2))is studied,in which dMSC-345 displays a doublet peaking at 328/345 *** suggest that the development is from the clusters that form in the initial prenucleation stage of the *** clusters are the precursor compound(PC-299)of MSC-299(displaying an absorption singlet peaking at 299 nm).PC-299 transforms to PC-345 at a later *** presence of alcohol(such as methanol or ethylene glycol)promotes another pathway,which is the PC-299 to PC-320 ***-320 transforms to dMSC-320(with a doublet at 305/320 nm),followed by dMSC-345 via *** present study provides additional evidence that clusters(PC-299)form and transform(such as to dMSC-345 via PC-345)in the prenucleation stage of ZnSe quantum dots(QDs).

关键词： magic-size cluster(MSC) prenucleation cluster precursor compound(PC) quantum dot(QD) zinc selenide(ZnSe)

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Particulate capillary precolumns with double-end polymer monolithic frits for on-line peptide trapping and preconcentration

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Chinese Chemical Letters 2015年第9期26卷 1068-1072页

作者： Si-Min Xia Hui-Ming yuan Zheng Liang Li-Hua Zhang yu-kui Zhang University of Chinese Academy of Science National Chromatographic R&A Center Dalian Institute of Chemical PhysicsThe Chinese Academy of Sciences

In this work,a novel kind of particulate capillary precolumns with double-end polymer monolithic frits has been ***,the polymer monolithic frit at one end was prepared via photo-initiated polymerization of a mixture of lauryl methacrylate and ethyleneglycol dimethacrylate with 1-propanol and 1,4-butanediol as porogens and 2,2-dimethoxy-2-phenylacetophenone as a photo-initiator in UV transparent coating capillary（100 μm i.d.）.Subsequently,C18 particles（5 μm,100 A） were packed into the capillary,and sealed with the polymer monolithic frit at another *** prevent the reaction of monomers and C18 particles,the packed C18 particles were masked during UV *** loading capacity of such a precolumn was determined to be about 9 μg by frontal analysis with a synthetic peptide APGDR1 YVHPF as a model ***,two parallel precolumns were incorporated into a two-dimensional nano-liquid chromatography（2D nano-LC） system with dual capillary trap columns for peptide trapping and *** to 2D nano-LC system with a single trap column,such two dimensional separations could be operated simultaneously to improve the analysis *** these results demonstrated that such capillary precolumns with double frits would be promising for high-throughput proteome analysis.

关键词： Capillary precolumn Double-end frits Peptide trapping 2D nano-LC

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