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Numerical Investigation on Inclined Hydraulic Transport of Large Particles for Deepsea Mining

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China Ocean Engineering 2023年第3期37卷 420-432页

作者： LIU Lei LI xin TIAN xin-liang zhanG Xian-tao xu Li-xin zhanG Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China

Hydraulic transport in pipelines is the most promising conveying method for large ore particles in deepsea *** dynamic performances of particles during transportation in vertical,inclined and horizontal pipelines are significant for the design of hydraulic transport *** the present study,we focus on the statistical characteristics and flow regimes of the mixture composed of ore particles and seawater in the *** simulations are conducted by using Computational Fluid Dynamics(CFD)and Discrete Element Method(DEM).The influences of inclination angle and particle diameter are evaluated through two sets of numerical *** regulation of the inclined transport is totally different from that of the vertical transport,whereas the dynamics of the mixtures in inclined and horizontal pipes are similar.A number of particles accumulate on the pipe wall even with a small inclination *** hydraulic gradient and local concentration would occur when the inclination angle of the pipe is in the range of30°-60°.With the decrease of particle diameter,the particle flow becomes uniform,reflected by the almost uniform particle distribution in the vertical pipe and the clear interface between the suspended load and the bed-load in the inclined ***,small particles will introduce larger local concentrations and hydraulic gradients in the inclined pipe,which is not conducive to particle transport.

关键词： deepsea mining hydraulic transport inclined pipe numerical simulation

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： xu Liang Ni-Hui zhang Zhi-Lai zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

An online BOF terminal temperature control model based on big data learning

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Journal of Iron and Steel Research International 2023年第5期30卷 875-886页

作者： Jia-wei guo Dong-ping zhan guo-cai xu Nai-hui Yang Bo Wang Ming-xin Wang Geng-wei You School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Jianlong Acheng Iron&Steel Co. Ltd.Harbin 150000HeilongjiangChina

The development of basic oxygen furnace(BOF)intelligent steelmaking model based on artificial intelligence and big data is the focus of international research and *** the view of the current situation that the BOF cannot continuously detect the composition and molten steel temperature,combined with the monitoring results of the high-definition and high-brightness camera at the converter mouth,an online BOF terminal temperature control model is established based on big data learning case-based reasoning model and expert system *** on-site online operation shows that the model can effectively improve the"flying lance"phenomenon and the splashing condition,the stability and safety of smelting process are better than that of artificial smelting,the"flying lance"rate decreases from 39.2% to 0,the early splashing rate decreases from 21.4% to 13.3% and the late splashing rate decreases from 81.25% to 56.7%.When the temperature fluctuation is controlled at±15 oC,the hit rate of the terminal temperature under the automatic control of the model is 90.91%.

关键词： Basic oxygen furnace Case-based reasoning Expert system Steelmaking Temperature

Research of stochastic weight strategy for extended particle swarm optimizer

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 122-124,134页

作者： xu Jun-jie YUE xin xin zhan-hong Economics and Management College Anqing Teachers CollegeAnqing 246133 China School of Economics and Management Beijing University of Posts andTelecommunications Beijing 100876 China

To improve the performance of extended particle swarm optimizer, a novel means of stochastic weight deployment is proposed for the iterative equation of velocity updation. In this scheme, one of the weights is specified to a random number within the range of [0, 1] and the other two remain constant configurations. The simulations show that this weight strategy outperforms the previous deterministic approach with respect to success rate and convergence speed. The experiments also reveal that if the weight for global best neighbor is specified to a stochastic number, extended particle swarm optimizer achieves high and robust performance on the given multi-modal function.

关键词： particle swarm optimization evolutionary computation,stochastic weight function optimization

Study on the share ratio between a service provider and two carriers

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 120-124页

作者： YUE xin xu Jun-jie xin zhan-hong School of Economics and Management Beijing University of Posts and Telecommunications Bcijing 100876 China

Based on the premise of obtaining optimal revenue, a mathematical model about operation strategies of service provider （SP） in duopoly telecom market was established in this article. In consideration of complexities, the model was transformed from a tri-game to two-party game model under four hypotheses. Nash equilibrium solution between SP and two carriers was proposed with detailed analyses. The value ranges under different cases provided a reference for carriers and SP while deciding share ratios.

关键词： duopoly marketk Nash equilibrium tri-game win-win game

Momentum Transfer of an Atom Moving in an Optical Cavity

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Chinese Physics Letters 2001年第8期18卷 1069-1071页

作者： zhanG Jing-tao xu Zhi-zhan Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

When an atom moves in an optical cavity,the total momentum of the atom does not keep *** study a two-level atom moving slowly in an optical cavity,and give the time dependence of its mean *** is found that when the initial momentum of the atom is larger than that of the photon,the mean momentum oscillates around a value less than the initial value,But,if the initial momentum is less than the momentum of the photon,the mean momentum of the atom is greater than its initial value in most time.

关键词： momentum value initial

Single cell tells the developmental story

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Science Bulletin 2016年第17期61卷 1355-1357页

作者： Zhengyan zhan xin xu Yu V.Fu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of Sciences

Stem cells are undifferentiated cells that retain the ability to self-renew and differentiate into specialized cells,offering a promising resource to generate requisite cell types in regenerative medicine[1,2].Haematopoietic stem cells(HSCs)can differentiate into entire mature blood lineages,sitting at the apex of the haematopoietic hierachy and playing a key role in the long-term maintenance and stabilization of mammalian blood system functions[3,4].HSCs are mostly found in embryo and bone marrow,but also with small amounts in peripheral ***

关键词： maintenance differentiate specialized stabilization embryo mature story retain offering developmental

Subfemtosecond X-ray Pulses Produced Directly by High Harmonic Generation

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Chinese Physics Letters 2000年第7期17卷 491-492页

作者： WANG Ying-song xu Zhi-zhan Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

The generation of subfemtosecond pulses in hydrogen-like atoms through high-harmonic generation by using superintense multicycle driver pulses is numerically investigated. It is shown that a single subfemtosecond pulse can be directly generated when the driver pulse is strong enough to deplete the neutral atoms within several optical cycles. The propagation effect is neglected during the numerical examinations.

关键词： femtosecond pulse neglected

Synthesis and characterization of imide modified poly(dimethylsiloxane) with maleopimaric acid as raw material

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Chinese Chemical Letters 2015年第5期26卷 572-574页

作者： tao xu He Liu Jie song Shi-Bin Shang zhan-Qian song Xiu-Jie Chen Chong Yang Institute of Chemical Industry of Forestry Products Chinese Academy of ForestryKey Laboratory of Biomass Energy and MaterialNational Engineering Laboratory for Biomass Chemical UtilizationKey and Open Laboratory on Forest Chemical EngineeringSFA Shenzhen Guanheng New Materials Technology Co. Ltd. Department of Chemistry and Biochemistry University of Michigan-Flint

With the natural rosin derivative （maleopimaric acid, MPA） as the raw material, imide modified vinyl poly（dimethylsiloxane）（MP-VMS） was synthesized and characterized by ^1H NMR and ^13C NMR. The curing kinetic parameters of MP-VMS were determined by differential scanning calorimetry （DSC） at various heating rates （5, 8, 10, 15 ℃/min） from the Kissingner, Ozawa and Crane methods. The activation energy （Ea）, pre-exponential factor （A） and reaction order （n） were respectively 18.6 kJ/mol, 71,108 and 0.902. The low-temperature and high-temperature resistance of its curing product were respectively investigated by DSC and thermogravimetric analysis. The results showed that incorporation of MPA could significantly improve the thermal stability of silicone while had no effect on the low-temperature resistance, and the Tmax （the temperature corresponding to the maximum weight loss rate） increased by 70.7 ℃.

关键词： Maleopimaric acid lmide Polysiloxane Curing kinetics Differential scanning calorimetry (DSC)