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Chinese Journal of Chemical Engineering 2024年第4期68卷 76-82页

作者： Shaoyun Wu zhuang ma Zichi Yang Suying Zhao Caijin Zhou Huidong Zheng Fujian Engineering Research Center of Advanced manufacturing Technology for Fine Chemicals College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou362114China

Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of microreactors.In this work,the novel curved capillary reactor with different shapes was designed to generate Dean flow,which was used to enhance the liquideliquid micromixing performance.The VillermauxeDushman probe reaction was employed to characterize the micromixing performance in different curved capillary microreactors.The effects of experiment parameters such as liquid flow rate,inner diameter,tube length,and curve diameter on micromixing performance were systematically investigated.Under the optimal conditions,the minimum value of the segmentation factor XS was 0.008.It was worth noting that at the low Reynolds number(Remance with XS reduced by 37.5%.Further,the correlations of segment index XS with dimensionless factor such as Reynolds number or Dean number were developed,which can be used to predict the liquide liquid micromixing performance in capillary microreactors.

关键词： Microreactor Process intensification Micromixing performance Dean flow

(Lu_(1/7)Yb_(1/7)Sc_(1/7)Er_(1/7)Y_(1/7)Ho_(1/7)Dy_(1/7))_(2)Si_(2)O_(7)high entropy rare-earth disilicate with low thermal conductivity and excellent resistance to CmaS corrosion

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Journal of Advanced Ceramics 2024年第5期13卷 549-560页

作者： Xu Wang Mingyu Meng Feihan Xu Ling Liu Lihong Gao Shizhen Zhu zhuang ma School of materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on materials under Shock and Impact Beijing 100081China Tangshan Research Institute Beijing Institute of TechnologyTangshan 063000China

Low thermal conductivity,compatible thermal expansion coefficient,and good calcium–magnesium–aluminosilicate(CmaS)corrosion resistance are critical requirements for environmental barrier coatings used on silicon-based ceramics.RE2Si2O7(RE=rare earth)has been widely recognized as one of the most promising candidates for environmental barrier coatings due to its good water vapor corrosion resistance.However,the relatively high thermal conductivity and poor resistance to CmaS corrosion have limited its practical application.Inspired by the high entropy effect,in this work,a novel rare earth disilicate(Lu_(_(1/7))Yb_(_(1/7))Sc_(_(1/7))Er_(_(1/7))Y_(_(1/7))Ho_(_(1/7))Dy_(_(1/7)))2Si2O7((7RE_(_(1/7)))2Si2O7)has been designed and synthesized by a solid reaction process.(7RE_(_(1/7)))2Si2O7 showed a low thermal conductivity of 1.81 W·m^(−1)·K^(−1)at 1273 K.Furthermore,the thermal expansion coefficient of(7RE_(_(1/7)))_(2)Si_(2)O_(7)(4.07×10^(−6)℃^(−1)from room temperature(RT)to 1400℃)is close to that of the SiC-based ceramic matrix composites(SiC-CMCs)((4.5–5.5)×10^(−6)℃^(−1)).Additionally,(7RE_(_(1/7)))2Si2O7 exhibited excellent resistance to CmaS corrosion.When exposed to CmaS at 1300℃for 48 h,the reaction layer thickness was 22μm.The improved performance of(7RE_(_(1/7)))2Si2O7 highlights its potential as a promising candidate for thermal/environmental barrier coatings.

关键词： high entropy disilicate (Lu_(1/7)Yb_(1/7)Sc_(1/7)Er_(1/7)Y_(1/7)Ho_(1/7)Dy_(1/7))_(2)Si_(2)O_(7)((7RE_(1/7))_(2)Si_(2)O_(7)) high-temperature thermal properties calcium-magnesium-aluminosilicate(CmaS)corrosion

Phase regimes of parity-time-symmetric coupled-ring systems at exceptional points

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Photonics Research 2022年第10期10卷 2374-2379页

作者： zhuang ma XIAOYAN ZHOU LIN ZHANG Tianjin Key Laboratory of Integrated Opto-electronics Technologies and Devices School of Precision Instruments and Opto-electronics EngineeringTianjin UniversityTianjin 300072China Peng Cheng Laboratory Shenzhen 518038China

The optical coupled resonant system consisting of an integrated resonator with gain and a resonator with loss provides an excellent platform to create exceptional points(EPs)in non-Hermitian systems.Most previous studies have focused on the striking intensity feature of EPs,but its phase response is seldom investigated.In this work,we present a thorough study on the phase response of an EP system.Intriguingly,the phase response exhibits distinct behavior depending on the ordering of the ring resonators:when the input light in a bus waveguide is coupled directly or indirectly to the ring with a gain,the phase response is featured by nonmonotonic transition and 2π monotonic transition,respectively.We also prove that the newly identified phase features are theoretically guaranteed.These phase responses produce unique group delays that have never been found in other coupled resonant systems.The results deepen our understanding on EPs in non-Hermitian systems and are potentially useful for practical applications exploiting phase features.

关键词： resonator waveguide coupled

Selective precipitation and non-isothermal crystallization kinetics of britholite from low grade REE-bearing slag

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Journal of Rare Earths 2023年第11期41卷 1812-1818,I0006页

作者： zhuang ma Zengwu Zhao Xingqi Guo Wentao Guo School of materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010China Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010China Inner Mongolia Autonomous Regional Engineering Technology Research Center of Sustainable Exploitation of Rare Earth Secondary Resources Inner Mongolia University of Science and TechnologyBaotou014010China

In order to improve the recovery rate of rare earth,the effect of P_(2)O_(5) and cooling rate on the selective precipitation of CaO-SiO_(2)-TiO_(2)-P_(2)O_(5)-Nb_(2)O_(5)-CeO_(2)-CaF_(2) slag system was explored using X-ray powder diffraction,a scanning electron microscope,an electron probe micro-analyzer and a confocal laser scanning microscope.The apatite(Ca_(2.02)Ce_(7.98)Si_(6.00)O_(26.00))is tiny and difficult to be separated from the slag without P_(2)O_(5).When the addition of P_(2)O_(5) is 6 wt%-10 wt%,the cerium and phosphorus are found to be enriched in britholite(Ca_(5-x)Ce_(x)[(SiO_(4))_(x)(PO_(4))_(3-x)]F)phase while x is negatively correlated with P_(2)O_(5) content in the slag.The influence of P_(2)O_(5) and cooling rate on the non-isothermal crystallization kinetics was also investigated.For the cooling rate between 5 and 40℃/min,continuous cooling transformation diagram of britholite was constructed when the P205 content is between 6 wt%-10 wt%.The modified Avrami model was applied to determine the crystallization mode of slag with 10 wt%P_(2)O_(5).It is shown that the crystallization mode is diffusion-controlled with constant nucleation rate and one-dimensional growth.In consideration of quantity and volume of crystals,the reasonable cooling rate is between 10and 30℃/min.

关键词： P_(2)O_(5) Crystallization Kinetics Low grade REE-bearing slag Rare earths

Wind Turbine Spindle Operating State Recognition and Early Warning Driven by SCADA Data

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Energy Engineering 2023年第5期120卷 1223-1237页

作者： Yuhan Liu Yuqiao Zheng zhuang ma Cang Wu School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou730050China

An operating condition recognition approach of wind turbine spindle is proposed based on supervisory control and data acquisition(SCADA)normal data drive.Firstly,the SCADA raw data of wind turbine under full working conditions are cleaned and feature extracted.Then the spindle speed is employed as the output parameter,and the single and combined normal behavior model of the wind turbine spindle is constructed sequentially with the preprocessed data,with the evaluation indexes selected as the optimal model.Finally,calculating the spindle operation status index according to the slidingwindowprinciple,ascertaining the threshold value for identifying the abnormal spindle operation status by the hypothesis of small probability event,analyzing the 2.5 MW wind turbine SCADA data froma domestic wind field as a sample,The results show that the fault warning time of the early warningmodel is 5.7 h ahead of the actual fault occurrence time,as well as the identification and early warning of abnormal wind turbine spindle operationwithout abnormal data or a priori knowledge of related faults.

关键词： Wind turbine SCADA data-driven state recognition early warning

Improved thermal stability and infrared emissivity of high-entropy REMgAl_(11)O_(19)and Lamal_(11)O_(19)(RE=La,Nd,Gd,Sm,Pr,Dy;M=Mg,Fe,Co,Ni,Zn)

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Journal of materials Science & Technology 2022年第9期104卷 131-144页

作者： Haolin Zhu Ling Liu Huimin Xiang Fu-Zhi Dai Xiaohui Wang zhuang ma Yanbo Liu Yanchun Zhou School of materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China National Key Laboratory of Science and Technology on materials under Shock and Impact Beijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

LaMgAl_(11)O_(19)(Lma),characterized by high melting point,low density and thermal conductivity as well as good infrared emissivity,is regarded as a potential candidate for the thermal protection of hypersonic vehicles.Nevertheless,the unsatisfied phase stability at high temperature results in declining of the emissivity below 6μm,which limits the extensive applications of LaMgAl_(11)O_(19).In order to overcome this obstacle,three dense bulk high-entropy ceramics,(La_(0.2)Nd_(0.2)Gd_(0.2)Sm_(0.2)Pr_(0.2))MgAl_(11)O_(19)(HE Lma-1),(La_(0.2)Nd_(0.2)Gd_(0.2)Sm_(0.2)Dy_(0.2))Mg Al_(11)O_(19)(HE Lma-2)and La(Mg_(0.2)Fe_(0.2)Co_(0.2)Ni_(0.2)Zn_(0.2))Al_(11)O_(19)(HE Lma-3),were designed and successfully prepared through solid state reaction at 1700℃for 4 h in one step.XRD analyses show that the phase compositions of HE Lma-1,HE Lma-2 and HE Lma-3 are single-phase solid solutions with the relative density of 95.61%,95.49%and 94.31%,respectively.Heat treatment experiments demonstrate that the phase composition of HE Lma-1 remains a single phase after high-temperature heating,while second phase appears in other two samples.The stability of HE Lma-1 is attributed to small average size differenceδ(~4%)of constitute elements.Intriguingly,the average emissivity of HE Lma-1 in the range of 3-6μm reaches 0.9,which is significantly higher than that of Lma and other two HE Lma samples.The emissivity of all samples remains above 0.95 from 6 to 10μm.In the far infrared region(10-14μm),although the emissivity of these specimens decreases slightly,it still exceeds 0.85.The UV-Vis absorption spectra indicate that the formation of many discrete impurity energy levels with small intervals in HE Lma-1 promotes the f electrons to transit between adjacent impurity energy levels and conduction band,which enhances the infrared emission of HE Lma-1 below 6μm.In a word,with improved phase stability and thermal emissivity in infrared range,high-entropy REMgAl_(11)O_(19),especially(La_(0.2)Nd_(0.2)Gd_(0.2)Sm_(0.2)Pr_(0.2))MgAl_(11)O_(19)(HE Lma-

关键词： High-entropy ceramics LaMgAl_(11)O_(19) Thermal stability Infrared emissivity UV-Vis absorption

Multiferroicity and giant in-plane negative Poisson’s ratio in wurtzite monolayers

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npj Computational materials 2022年第1期8卷 489-499页

作者： zhuang ma Pu Huang Jin Li Peng Zhang Jiaxin Zheng Wen Xiong Fei Wang Xiuwen Zhang Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen University518060ShenzhenChina School of Advanced materials Peking UniversityShenzhen Graduate School518055ShenzhenChina Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences400714ChongqingChina School of Physics and Microelectronics Zhengzhou University450001ZhengzhouChina

Monolayers of layered materials,such as graphite and molybdenum dichalcogenides,have been the focus of materials science in the last decades.Here,we reveal benign stability and intriguing physical properties in the thinnest monolayer wurtzite(wz)semiconductors,which can be exfoliated from their bulk and stacked to reform the wz crystals.The candidate ZnX and CdX(X=S,Se,Te)monolayers possess low cleavage energy and direct bandgaps,which harbor strongly coupled ferroelectricity and ferroelasticity with low transition barriers,giant in-plane negative Poisson’s ratio,as well as giant Rashba spin splitting,enabling the co-tunability of spin splitting and auxetic magnitudes via multiferroic switching.These wz monolayers can be used as building blocks of devices structures,due to their inherent“self-healable”capacity,which offer more flexibility for semiconductor fabrication and provide a natural platform to probe the interplay of multiple physical effects,bringing light into the rich physics in tetrahedral semiconductors.

关键词： plane splitting molybdenum

考虑故障风险与不确定性的海上风电主变压器检修策略

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电力科学与技术学报 2024年第2期39卷 214-222页

作者：马壮淡淑恒上海电力大学电气工程学院上海200090

为提高海上风电主变压器检修策略优化的科学性,在保证可靠运行的前提下,提出一种考虑故障风险与不确定性的海上风电主变压器检修策略优选方法。首先,详细分析故障风险成本模型,据此建立海上风电主变压器全寿命周期成本(life cycle cost,... 详细信息

为提高海上风电主变压器检修策略优化的科学性,在保证可靠运行的前提下,提出一种考虑故障风险与不确定性的海上风电主变压器检修策略优选方法。首先,详细分析故障风险成本模型,据此建立海上风电主变压器全寿命周期成本(life cycle cost,LCC)模型,并引入盲数理论将LCC中不确定性参数用数学模型定量进行计算,提高成本估算精度。然后,从成本管理角度出发,分析维修方案对LCC的影响,进而建立以LCC最低为目标的海上风电主变压器检修策略优化模型,并通过改进的布谷鸟搜索算法进行求解。最后,经算例验证,所提模型和检修策略优选方法具有较强的可操作性,能为海上风电主变压器的可靠运行提供一定的参考价值。

关键词：海上风电主变压器故障风险 LCC 盲数理论改进的布谷鸟搜索算法检修策略

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Atomic-resolution investigation of structural transformation caused by oxygen vacancy in La_(0.9)Sr_(0.1)TiO_(3+δ)titanate layer perovskite ceramics

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Journal of materials Science & Technology 2022年第9期104卷 172-182页

作者： Yang Zhao Yameng Zhu Jinpeng Zhu Hailong Wang zhuang ma Lihong Gao Yanbo Liu Kaijun Yang Yongchun Shu Jilin He Henan Province Industrial Technology Research Institute of Resources and materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China National Key Laboratory of Science and Technology on materials under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Perovskite functional ceramics have been widely applied for thermal protection owing to their unique physical properties.However,formation of oxygen vacancies under external stimuli usually limits their performance in practical applications.Therefore,the mechanism of the effect of oxygen vacancy on the layer structure of perovskite La_(0.9)Sr_(0.1)TiO_(3+δ)was investigated by experiments and first-principles simulations.The experimental results showed that the lattice distortion occurred in oxygen-deficient environment to give a longer c-axis,along with a significant adjustment in the modes of A/B–O bond vibration,resulting in lower reflectivity.Advanced transmission electron microscopy studies revealed that oxygen vacancies induced localized atomic rearrangements via[TiO_(6)]layer movements to adapt to the lattice distortion.This eventually restructured a part of the layer interfaces by expanding the overlapping projection of atoms in the c-axial direction.The specific transformation process was described as a compendious process,while geometric phase analysis effectively clarified how oxygen vacancies can inhibit reflectivity on the layer structure.Thus,this study provides effective approaches for researching the effects of oxygen vacancy on the physical properties of orthorhombic layer perovskite structures,which may facilitate the development of perovskite-based functional devices.

关键词： Titanate perovskite Oxygen vacancy Atomic rearrangement Optical reflectivity

Methods to increase the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic lesions:An updated review

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World Journal of Gastrointestinal Endoscopy 2024年第3期16卷 117-125页

作者： Xin Yang Zi-Ming Liu Xue Zhou Fan Yang Wen-zhuang ma Xin-Zhu Sun Si-Yu Sun Nan Ge Department of Gastroenterology Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina

Endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)is a means to procure adequate specimens for histological and cytologic analysis.The ideal EUS-FNA should be safe,accurate,and have a high sample adequacy rate and low adverse events rate.In recent years,many guidelines and trials on EUS-FNA have been published.The purpose of this article is to provide an update on the influence of some of the main factors on the diagnostic efficiency of EUS-FNA as well as a rare but serious complication known as needle tract seeding.

关键词： Endoscopic ultrasound EUS-FNA Pancreatic cancer Diagnostic efficiency