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Numerical study on morphological characteristics of rotational natural supercavitation by rotational supercavitating evaporator with optimized blade shape

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Journal of Hydrodynamics 2020年第3期32卷 468-485页

作者： Zhi-ying zheng Qian Li Lu Wang Li-ming Yao Wei-hua Cai Hui Li Feng-chen Li School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Department of Nuclear Engineering Kyoto UniversityKyotoJapan College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China Institute of Advanced Technology Heilongjiang Academy of SciencesHarbin 150020China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

In view of the supercavitation effect, a novel device named the rotational supercavitating evaporator (RSCE) has been designed for the desalination. In order to improve the blade shape of the rotational cavitator in the RSCE for the performance optimization, the blade shapes of different sizes are designed by utilizing the improved calculation method for the blade shape and the validated empirical formulae based on previous two-dimensional numerical simulations, from which the optimized blade shape with the wedge angle of 45° and the design speed of 5 000 r/min is selected. The estimation method for the desalination performance parameters is developed to validate the feasibility of the utilization of the results obtained by the two-dimensional numerical simulations in the design of the three-dimensional blade shape. Three-dimensional numerical simulations are then conducted for the supercavitating flows around the rotational cavitator with the optimized blade shape at different rotational speeds to obtain the morphological characteristics of the rotational natural supercavitation. The results show that the profile of the supercavity tail is concaved toward the inside of the supercavity due to the re-entrant jet. The empirical formulae for estimating the supercavity size with consideration of the rotation are obtained by fitting the data, with the exponents different from those obtained by the previous two-dimensional numerical simulations. The influences of the rotation on the morphological characteristics are analyzed from the perspectives of the tip and hub vortices and the interaction between the supercavity tail and the blade. Further numerical simulation of the supercavitating flow around the rotational cavitator made up by the blades with exit edge of uniform thickness illustrate that the morphological characteristics are also affected by the blade shape.

关键词： Rotational natural supercavitation morphological characteristics blade shape computational fluid dynamics(CFD)numerical simulation rotational supercavitating evaporator

Optimal Policies for Quantum Markov Decision Processes

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International Journal of Automation and computing 2021年第3期18卷 410-421页

作者： ming-Sheng ying Yuan Feng Sheng-Gang ying Centre for Quantum Software and Information University of Technology SydneyNSW 2007Australia State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China

Markov decision process(MDP)offers a general framework for modelling sequential decision making where outcomes are *** particular,it serves as a mathematical framework for reinforcement *** paper introduces an extension of MDP,namely quantum MDP(q MDP),that can serve as a mathematical model of decision making about quantum *** develop dynamic programming algorithms for policy evaluation and finding optimal policies for q MDPs in the case of *** results obtained in this paper provide some useful mathematical tools for reinforcement learning techniques applied to the quantum world.

关键词： Quantum Markov decision processes quantum machine learning reinforcement learning dynamic programming decision making

Self-assembled core-shell polydopamine@MXene with synergistic solar absorption capability for highly efficient solar-to-vapor generation

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Nano Research 2020年第1期13卷 255-264页

作者： Xing Zhao Xiang-Jun Zha Li-Sheng Tang Jun-Hong Pu Kai Ke Rui-ying Bao zheng-ying Liu ming-Bo Yang Wei Yang College of Polymer Science and Engineering Sichuan UniversityState Key Laboratory of Polymer Materials EngineeringChengdu610065China

As a renewable and environment-friendly technology for seawater desalination and wastewater purification,solar energy triggered steam generation is attractive to address the long-standing global water scarcity ***,practical utilization of solar energy for steam generation is severely restricted by the complex synthesis,low energy conversion efficiency,insufficient solar spectrum absorption and water extraction capability of state-of-the-art ***,for the first time,we report a facile strategy to realize hydrogen bond induced self-assembly of a polydopamine(PDA)@MXene microsphere photothermal layer for synergistically achieving wide-spectrum and highly efficient solar absorption capability(≈96%in a wide solar spectrum range of 250–1,500 nm wavelength).Moreover,such a system renders fast water transport and vapor escaping due to the intrinsically hydrophilic nature of both MXene and PDA,as well as the interspacing between core-shell *** solar-to-vapor conversion efficiencies under the solar illumination of 1 sun and 4 sun are as high as 85.2%and 93.6%,***,the PDA@MXene photothermal layer renders the system durable mechanical properties,allowing producing clean water from seawater with the salt rejection rate beyond 99%.Furthermore,stable light absorption performance can be achieved and well maintained due to the formation of ternary TiO2/C/MXene complex caused by oxidative degradation of ***,this work proposes an attractive MXene-assisted strategy for fabricating high performance photothermal composites for advanced solar-driven seawater desalination applications.

关键词： self-assembly polydopamine(PDA)@MXene microsphere synergistic light absorption solar-to-vapor generation light absorption stability

Synthesis of Inorganic Silica Grafted Three-arm PLLA and Their Behaviors for PLA Matrix

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Chinese Journal of Polymer Science 2019年第3期37卷 216-226页

作者： Da-Wei Shi Xiang-Ling Lai Yuan-Ping Jiang Cong Yan zheng-ying Liu Wei Yang ming-Bo Yang State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University

The low melt strength and poor crystallization behavior severely limit the processing and application of poly(lactic acid)(PLA) as biodegradable film materials. In this work, three-arm poly(L-lactic acid)(3A-PLLA) grafted silica nanoparticles with two kinds of topology structures were introduced into PLA matrix to improve the biodegradation performance. Different methods were used to characterize the structure of the grafted 3A-PLLA chains, the grafting density, and the thermal decomposition behavior of the nanoparticles. By varying the mass ratios of raw materials and altering the order of dropping solution in the reaction, high grafting densitytangled 3A-PLLA grafted SiO_2 was synthesized as "3A-PLLA grafting to SiO_2"(GTS), while low grafting density-stretched 3A-PLLA grafted SiO_2 was obtained as "SiO_2 grafting to 3A-PLLA"(GTA). Topology of nanoparticles as well as the filler-matrix interaction is critically important to structure bio-nanocomposites with desirable properties. Thus, the GTS and GTA nanoparticles were introduced into PLA matrix to assess the effect. The SEM images showed the uniform dispersion of the modified nanoparticles, while the shear rheology results revealed that GTA nanoparticles made a more significant contribution on the melt-strengthening and relaxation time-extension of PLA. Moreover, it is suggested that GTA nanoparticles were more effective to act as a nucleating agent for PLA, which was proved by differential scanning calorimetry(DSC) and polarized optical microscopy(POM) researches. All of the improvements mentioned above of GTA nanocomposites can be ascribed to stronger entanglements between 3A-PLLA stretched by nano-SiO_2 and PLA matrix.

关键词： Poly(lactic acid) Nanocomposites Surface grafting Topology Crystallization

Magnetic properties of α-Fe_2O_3 nanopallets

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Rare Metals 2019年第1期38卷 14-19页

作者： ying-ying Xu Long Wang Tong Wu Rong-ming Wang Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science School of Mathematics and PhysicsUniversity of Science and Technology Beijing Department of Equipment Manufacture Zhongshan Torch Polytechnic Division of Energy and Environmental Measurement National Institute of Metrology

It is the result of a systemic study about uniform hematite nanopallets with length of about 100 nm, width of about 30 nm, and thickness of less than 10 nm. The sample has superparamagnetic(SPM) properties above the blocking temperature of ～16 K. The temperature dependence of magnetization was well fitted by Bloch T^(3/2) law considering the dipolar interaction of the particles. The field dependence of magnetization was fitted with revised Langevin *** magnetization of the weak ferromagnetic(WF) canted spins contributes to the linear portion in the high field region;the surface uncompensated spins and the parasitic ferromagnetic moments due to the canted spins both contribute to the particle moments and the superparamagnetic behavior.

关键词： α-Fe2O3 nanopallets Magnetic property Superparamagnetic behavior Canted spins

半导体量子点分子-腔光机械耦合系统中光学双稳及多稳态的形成及调控

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原子与分子物理学报 2025年第5期42卷 115-122页

作者：曾莹任波徐名琪杨红佘彦超吉首大学物理与机电工程学院吉首416000 铜仁学院物理与电子工程系铜仁554300

本研究探讨了外部磁场对半导体量子点分子与腔光机械耦合系统中光学双稳态行为的影响.研究结果显示,外部磁场、量子点之间的隧穿耦合以及探测光单光子的失谐可以有效地调控系统的光学双稳态.在弱隧穿和弱磁场条件下,系统的光学双稳态阈... 详细信息

本研究探讨了外部磁场对半导体量子点分子与腔光机械耦合系统中光学双稳态行为的影响.研究结果显示,外部磁场、量子点之间的隧穿耦合以及探测光单光子的失谐可以有效地调控系统的光学双稳态.在弱隧穿和弱磁场条件下,系统的光学双稳态阈值和磁滞回线宽度随着外部磁场和点间隧穿耦合强度的增加而增大.随着磁场强度和隧穿耦合强度的进一步增加,系统的双稳态将演变为多稳态.有趣的是,在强隧穿和强磁场作用下,系统的光学双稳态阈值和磁滞回线宽度随着外部磁场和点间隧穿耦合强度的增加而减小.这种对耦合腔光机械系统中光学双稳态的灵活调控将在可控光开关方面具有潜在的广泛应用前景.

关键词：双稳态多稳态点间隧穿耦合光力耦合

Immobilizing Triphenylamine with Photoredox Inert Sr^(2+)Forming Sr-MOF with Controlled Electron Migration for Photocatalytic Oxidation of Thiols to Disulfides

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Chinese Journal of Chemistry 2024年第10期42卷 1093-1099页

作者： ying-Xia Wang Fang zheng Dong-Xia Song Bao-Yue Niu Lu-Qian Deng Xian-ming Zhang Key Laboratory of Magnetic Molecules and Magnetic Information Materials(Ministry of Education) Schoolof Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi 030006China Key Laboratory of Interface Science and Engineering in Advanced Material(Ministry of Education) College of ChemistryTaiyuan University of TechnologyTaiyuanShanxi 030024China

The photocatalytic oxidative coupling of thiols is one of the most popular methods to synthesize the *** and its derivatives(TPAs)are promising for the above reaction,but suffer from the easy polymerization and difficult *** overcome these obstacles while controlling the photogenerated electrons transfer directly to target substrates,herein,we constructed one TPA-based metal-organic framework(MOF),(Me_(2)NH_(2))[Sr(TCBPA)]·DMA·3H_(2)O(1),by direct self-assembly of tris(4′-carboxybiphenyl)amine(H_(3)TCBPA)and photoredox inert strontium ion(Sr^(2+)).DFT calculations revealed that the valence band maximum(VBM)and the conduction band minimum(CBM)are mainly located on TCBPA^(3-),successfully inhibiting the undesirable electron migration to metal *** results indicated that 1 displays superior performance than homogeneous H_(3)TCBPA,which may result from the abundant π…π and C—H…π interactions between the well-arranged TCBPA^(3-)and the build-in electric field between the anionic framework and the Me_(2)NH^(2+).This work highlights that immobilizing TPAs into MOFs is one promising approach to designing heterogeneous photocatalysts for the synthesis of disulfides by oxidative coupling of thiols.

关键词： Triphenylamine Metal-organic frameworks Strontium Photooxidation Thiols Disulfides

Decision framework of group consensus with hesitant fuzzy linguistic preference relations

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CAAI Transactions on Intelligence Technology 2020年第3期5卷 157-164页

作者： Yang Lin ying-ming Wang School of Economics Fujian Normal University350117 FuzhouPeople’s Republic of China Decision Science Institute Fuzhou University350116 FuzhouPeople’s Republic of China

Group decision making typically requires eliciting and coordinating the preferences of group *** this study,the authors develop an overall framework of group consensus in context of hesitant fuzzy linguistic preference relations(HFLPRs).A new notion of distance measure between two HFLPRs is defined,based on which a consensual framework consists of two mechanisms,the automatic consensus reaching and the interactive consensus reaching is ***,they,respectively,design two algorithms to implement these ***,a group decision problem of green supplier selection is provided to exemplify and verify both of the proposed methods,and a comparative analysis with some related approaches is performed.

关键词： verify typically notion

Sythesis, Characterization and Catalysis of [ η~5,η~1-C_5H_4-CHPh-PhO]TiCl_2

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Chemical Research in Chinese Universities 2001年第1期17卷 115-116页

作者： WANG Jian hui MU ying PU Wei ming ZHANG Yue tao YANG Guang di LIU Ju zheng Department of Chemistry Jilin UniversityChangchun 130023P.R.China

The synthesis and structure of phenol groups containing ligand 2-[(cyclopentadienyl-phenyl)-methyl]phenol(CpH-PhCH-PhOH) were described. H Nuclear magnetic resonance (NMR) was used to show existence of ligand precursor in isomers of the group. Me3SiCp-PhCH-PhOSiMe3 was formed via treatment of 2 mol Me3SiCl with the dilithium salt of the ligand. New Ti compound [η+5, η1-C5H4-PhCH-PhO]TiCl2 was formed by reacting with titanium chloride.

关键词： Metallocene Catalyst Cyclopentadienyl group